Sample records for safe boundaries bases

  1. Planetary boundaries: exploring the safe operating space for humanity

    Treesearch

    Johan Rockström; Will Steffen; Kevin Noone; Asa Persson; F. Stuart Chapin; Eric Lambin; Timothy M. Lenton; Marten Scheffer; Carl Folke; Hans Joachim Schellnhuber; Björn Nykvist; Cynthia A. de Wit; Terry Hughes; Sander van der Leeuw; Henning Rodhe; Sverker Sörlin; Peter K. Snyder; Robert Costanza; Uno Svedin; Malin Falkenmark; Louise Karlberg; Robert W. Corell; Victoria J. Fabry; James Hansen; Brian Walker; Diana Liverman; Katherine Richardson; Paul Crutzen; Jonathan Foley

    2009-01-01

    Anthropogenic pressures on the Earth System have reached a scale where abrupt global environmental change can no longer be excluded. We propose a new approach to global sustainability in which we define planetary boundaries within which we expect that humanity can operate safely. Transgressing one or more planetary boundaries may be deleterious or even catastrophic due...

  2. Understanding the occupational and organizational boundaries to safe hospital discharge.

    PubMed

    Waring, Justin; Marshall, Fiona; Bishop, Simon

    2015-01-01

    Safe hospital discharge relies upon communication and coordination across multiple occupational and organizational boundaries. Our aim was to understand how these boundaries can exacerbate health system complexity and represent latent sociocultural threats to safe discharge. An ethnographic study was conducted in two local health and social care systems (health economies) in England, focusing on two clinical areas: stroke and hip fracture patients. Data collection involved 345 hours of observations and 220 semi-structured interviews with health and social care professionals, patients and their lay carers. Hospital discharge involves a dynamic network of interactions between heterogeneous health and social care actors, each characterized by divergent ways of organizing discharge activities; cultures of collaboration and interaction and understanding of what discharge involves and how it contributes to patient recovery. These interrelated dimensions elaborate the occupational and organisational boundaries that can influence communication and coordination in hospital discharge. Hospital discharge relies upon the coordination of multiple actors working across occupational and organizational boundaries. Attention to the sociocultural boundaries that influence communication and coordination can help inform interventions that might support enhanced discharge safety. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  3. A safe operating space for humanity

    Treesearch

    Johan Rockström; Will Steffen; Kevin Noone; Asa Persson; F. Stuart Chapin; Eric F. Lambin; Timothy M. Lenton; Marten Scheffer; Carl Folke; Hans Joachim Schellnhuber; Björn Nykvist; Cynthia A. de Wit; Terry Hughes; Sander van der Leeuw; Henning Rodhe; Sverker Sörlin; Peter K. Snyder; Robert Costanza; Uno Svedin; Malin Falkenmark; Louise Karlberg; Robert W. Corell; Victoria J. Fabry; James Hansen; Brian Walker; Diana Liverman; Katherine Richardson; Paul Crutzen; Jonathan A. Foley

    2009-01-01

    To meet the challenge of maintaining the Holocene state, we propose a framework based on 'planetary boundaries'. These boundaries define the safe operating space for humanity with respect to the Earth system and are associated with the planet's biophysical subsystems or processes. Although Earth's complex systems sometimes respond smoothly to...

  4. From Planetary Boundaries to national fair shares of the global safe operating space - How can the scales be bridged?

    NASA Astrophysics Data System (ADS)

    Häyhä, Tiina; Cornell, Sarah; Lucas, Paul; van Vuuren, Detlef; Hoff, Holger

    2016-04-01

    The planetary boundaries framework proposes precautionary quantitative global limits to the anthropogenic perturbation of crucial Earth system processes. In this way, it marks out a planetary 'safe operating space' for human activities. However, decisions regarding resource use and emissions are mostly made at much smaller scales, mostly by (sub-)national and regional governments, businesses, and other local actors. To operationalize the planetary boundaries, they need to be translated into and aligned with targets that are relevant at these smaller scales. In this paper, we develop a framework that addresses the three dimension of bridging across scales: biophysical, socio-economic and ethical, to provide a consistent universally applicable approach for translating the planetary boundaries into national level context-specific and fair shares of the safe operating space. We discuss our findings in the context of previous studies and their implications for future analyses and policymaking. In this way, we help link the planetary boundaries framework to widely- applied operational and policy concepts for more robust strong sustainability decision-making.

  5. Predicting Loss-of-Control Boundaries Toward a Piloting Aid

    NASA Technical Reports Server (NTRS)

    Barlow, Jonathan; Stepanyan, Vahram; Krishnakumar, Kalmanje

    2012-01-01

    This work presents an approach to predicting loss-of-control with the goal of providing the pilot a decision aid focused on maintaining the pilot's control action within predicted loss-of-control boundaries. The predictive architecture combines quantitative loss-of-control boundaries, a data-based predictive control boundary estimation algorithm and an adaptive prediction method to estimate Markov model parameters in real-time. The data-based loss-of-control boundary estimation algorithm estimates the boundary of a safe set of control inputs that will keep the aircraft within the loss-of-control boundaries for a specified time horizon. The adaptive prediction model generates estimates of the system Markov Parameters, which are used by the data-based loss-of-control boundary estimation algorithm. The combined algorithm is applied to a nonlinear generic transport aircraft to illustrate the features of the architecture.

  6. Model-based estimation with boundary side information or boundary regularization [cardiac emission CT].

    PubMed

    Chiao, P C; Rogers, W L; Fessler, J A; Clinthorne, N H; Hero, A O

    1994-01-01

    The authors have previously developed a model-based strategy for joint estimation of myocardial perfusion and boundaries using ECT (emission computed tomography). They have also reported difficulties with boundary estimation in low contrast and low count rate situations. Here they propose using boundary side information (obtainable from high resolution MRI and CT images) or boundary regularization to improve both perfusion and boundary estimation in these situations. To fuse boundary side information into the emission measurements, the authors formulate a joint log-likelihood function to include auxiliary boundary measurements as well as ECT projection measurements. In addition, they introduce registration parameters to align auxiliary boundary measurements with ECT measurements and jointly estimate these parameters with other parameters of interest from the composite measurements. In simulated PET O-15 water myocardial perfusion studies using a simplified model, the authors show that the joint estimation improves perfusion estimation performance and gives boundary alignment accuracy of <0.5 mm even at 0.2 million counts. They implement boundary regularization through formulating a penalized log-likelihood function. They also demonstrate in simulations that simultaneous regularization of the epicardial boundary and myocardial thickness gives comparable perfusion estimation accuracy with the use of boundary side information.

  7. Opportunities and trade-offs of biomass based negative emissions within planetary boundaries

    NASA Astrophysics Data System (ADS)

    Heck, Vera; Gerten, Dieter; Lucht, Wolfgang

    2017-04-01

    The Paris Agreement requires "a balance between anthropogenic emissions by sources and removals by sinks of greenhouse gases in the second half of the century" (UNFCCC, 2015). Without a full decarbonization of the energy and land use sector until the second half of this century, negative emission technologies (NETs) are required to achieve net zero greenhouse gas emissions. Integrated assessment studies indicate that bioenergy with carbon capture and storage (BECCS), a land based NET, has the potential to contribute substantially to balancing anthropogenic fossil fuel emissions. However, significant negative emission potentials from BECCS require substantial biomass potentials, which can only be achieved by intensively managed (fertilized and irrigated) large-scale biomass plantations. Additional to direct trade-offs of land and water availability, the implementation of large-scale biomass plantations implies major restructuring of the land surface on top of existing land use and would be accompanied by indirect trade-offs such as changes in moisture and energy fluxes. In the context of the planetary boundaries framework as proposed by Rockström et al. (2009), BECCS might contribute to reduce the transgression of the planetary boundary (PB) for climate change, but would most likely steer the Earth system closer to the PB for freshwater use and lead to further transgression of the PBs for land system change, biosphere integrity and biogeochemical flows. This presentation will investigate the opportunities of second generation biomass potentials within the safe operating space for humanity and highlight the multidimensional trade-offs between biomass potentials for BECCS in relation to the PBs. Scenarios of land availability for biomass plantations and land based carbon sequestration were developed with a spatially explicit multi-criterial optimization framework, considering the precautionary need to stay within the safe operating space vis-à-vis the need to

  8. Voting based object boundary reconstruction

    NASA Astrophysics Data System (ADS)

    Tian, Qi; Zhang, Like; Ma, Jingsheng

    2005-07-01

    A voting-based object boundary reconstruction approach is proposed in this paper. Morphological technique was adopted in many applications for video object extraction to reconstruct the missing pixels. However, when the missing areas become large, the morphological processing cannot bring us good results. Recently, Tensor voting has attracted people"s attention, and it can be used for boundary estimation on curves or irregular trajectories. However, the complexity of saliency tensor creation limits its applications in real-time systems. An alternative approach based on tensor voting is introduced in this paper. Rather than creating saliency tensors, we use a "2-pass" method for orientation estimation. For the first pass, Sobel d*etector is applied on a coarse boundary image to get the gradient map. In the second pass, each pixel puts decreasing weights based on its gradient information, and the direction with maximum weights sum is selected as the correct orientation of the pixel. After the orientation map is obtained, pixels begin linking edges or intersections along their direction. The approach is applied to various video surveillance clips under different conditions, and the experimental results demonstrate significant improvement on the final extracted objects accuracy.

  9. Steering teens safe: a randomized trial of a parent-based intervention to improve safe teen driving.

    PubMed

    Peek-Asa, Corinne; Cavanaugh, Joseph E; Yang, Jingzhen; Chande, Vidya; Young, Tracy; Ramirez, Marizen

    2014-07-31

    Crashes are the leading cause of death for teens, and parent-based interventions are a promising approach. We assess the effectiveness of Steering Teens Safe, a parent-focused program to increase safe teen driving. Steering Teens Safe aimed to improve parental communication with teens about safe driving using motivational interviewing techniques in conjunction with 19 safe driving lessons. A randomized controlled trial involved 145 parent-teen dyads (70 intervention and 75 control). Intervention parents received a 45-minute session to learn the program with four follow-up phone sessions, a DVD, and a workbook. Control parents received a standard brochure about safe driving. Scores were developed to measure teen-reported quantity and quality of parental communication about safe driving. The main outcome measure was a previously validated Risky Driving Score reported by teens. Because the Score was highly skewed, a generalized linear model based on a gamma distribution was used for analysis. Intervention teens ranked their parent's success in talking about driving safety higher than control teens (p = 0.035) and reported that their parents talked about more topics (non-significant difference). The Risky Driving Score was 21% lower in intervention compared to control teens (85% CI = 0.60, 1.00). Interaction between communication quantity and the intervention was examined. Intervention teens who reported more successful communication had a 42% lower Risky Driving Score (95% CI = 0.37, 0.94) than control parents with less successful communication. This program had a positive although not strong effect, and it may hold the most promise in partnership with other programs, such as Driver's Education or Graduated Driver's License policies. ClinicalTrials.gov NCT01014923. Registered Nov. 16, 2009.

  10. How to bring absolute sustainability into decision-making: An industry case study using a Planetary Boundary-based methodology.

    PubMed

    Ryberg, Morten W; Owsianiak, Mikołaj; Clavreul, Julie; Mueller, Carina; Sim, Sarah; King, Henry; Hauschild, Michael Z

    2018-09-01

    The Planetary Boundaries concept has emerged as a framework for articulating environmental limits, gaining traction as a basis for considering sustainability in business settings, government policy and international guidelines. There is emerging interest in using the Planetary Boundaries concept as part of life cycle assessment (LCA) for gauging absolute environmental sustainability. We tested the applicability of a novel Planetary Boundaries-based life cycle impact assessment methodology on a hypothetical laundry washing case study at the EU level. We express the impacts corresponding to the control variables of the individual Planetary Boundaries together with a measure of their respective uncertainties. We tested four sharing principles for assigning a share of the safe operating space (SoSOS) to laundry washing and assessed if the impacts were within the assigned SoSOS. The choice of sharing principle had the greatest influence on the outcome. We therefore highlight the need for more research on the development and choice of sharing principles. Although further work is required to operationalize Planetary Boundaries in LCA, this study shows the potential to relate impacts of human activities to environmental boundaries using LCA, offering company and policy decision-makers information needed to promote environmental sustainability. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. An urban approach to planetary boundaries.

    PubMed

    Hoornweg, Daniel; Hosseini, Mehdi; Kennedy, Christopher; Behdadi, Azin

    2016-09-01

    The achievement of global sustainable development goals subject to planetary boundaries will mostly be determined by cities as they drive cultures, economies, material use, and waste generation. Locally relevant, applied and quantitative methodologies are critical to capture the complexity of urban infrastructure systems, global inter-connections, and to monitor local and global progress toward sustainability. An urban monitoring (and communications) tool is presented here illustrating that a city-based approach to sustainable development is possible. Following efforts to define and quantify safe planetary boundaries in areas such as climate change, biosphere integrity, and freshwater use, this paper modifies the methodology to propose boundaries from a city's perspective. Socio-economic boundaries, or targets, largely derived from the Sustainable Development Goals are added to bio-physical boundaries. Issues such as data availability, city priorities, and ease of implementation are considered. The framework is trialed for Toronto, Shanghai, Sao Paulo, Mumbai, and Dakar, as well as aggregated for the world's larger cities. The methodology provides an important tool for cities to play a more fulsome and active role in global sustainable development.

  12. Sustainability. Planetary boundaries: guiding human development on a changing planet.

    PubMed

    Steffen, Will; Richardson, Katherine; Rockström, Johan; Cornell, Sarah E; Fetzer, Ingo; Bennett, Elena M; Biggs, Reinette; Carpenter, Stephen R; de Vries, Wim; de Wit, Cynthia A; Folke, Carl; Gerten, Dieter; Heinke, Jens; Mace, Georgina M; Persson, Linn M; Ramanathan, Veerabhadran; Reyers, Belinda; Sörlin, Sverker

    2015-02-13

    The planetary boundaries framework defines a safe operating space for humanity based on the intrinsic biophysical processes that regulate the stability of the Earth system. Here, we revise and update the planetary boundary framework, with a focus on the underpinning biophysical science, based on targeted input from expert research communities and on more general scientific advances over the past 5 years. Several of the boundaries now have a two-tier approach, reflecting the importance of cross-scale interactions and the regional-level heterogeneity of the processes that underpin the boundaries. Two core boundaries—climate change and biosphere integrity—have been identified, each of which has the potential on its own to drive the Earth system into a new state should they be substantially and persistently transgressed. Copyright © 2015, American Association for the Advancement of Science.

  13. Stochastic Resonance and Safe Basin of Single-Walled Carbon Nanotubes with Strongly Nonlinear Stiffness under Random Magnetic Field.

    PubMed

    Xu, Jia; Li, Chao; Li, Yiran; Lim, Chee Wah; Zhu, Zhiwen

    2018-05-04

    In this paper, a kind of single-walled carbon nanotube nonlinear model is developed and the strongly nonlinear dynamic characteristics of such carbon nanotubes subjected to random magnetic field are studied. The nonlocal effect of the microstructure is considered based on Eringen’s differential constitutive model. The natural frequency of the strongly nonlinear dynamic system is obtained by the energy function method, the drift coefficient and the diffusion coefficient are verified. The stationary probability density function of the system dynamic response is given and the fractal boundary of the safe basin is provided. Theoretical analysis and numerical simulation show that stochastic resonance occurs when varying the random magnetic field intensity. The boundary of safe basin has fractal characteristics and the area of safe basin decreases when the intensity of the magnetic field permeability increases.

  14. Safe Grid

    NASA Technical Reports Server (NTRS)

    Chow, Edward T.; Stewart, Helen; Korsmeyer, David (Technical Monitor)

    2003-01-01

    The biggest users of GRID technologies came from the science and technology communities. These consist of government, industry and academia (national and international). The NASA GRID is moving into a higher technology readiness level (TRL) today; and as a joint effort among these leaders within government, academia, and industry, the NASA GRID plans to extend availability to enable scientists and engineers across these geographical boundaries collaborate to solve important problems facing the world in the 21 st century. In order to enable NASA programs and missions to use IPG resources for program and mission design, the IPG capabilities needs to be accessible from inside the NASA center networks. However, because different NASA centers maintain different security domains, the GRID penetration across different firewalls is a concern for center security people. This is the reason why some IPG resources are been separated from the NASA center network. Also, because of the center network security and ITAR concerns, the NASA IPG resource owner may not have full control over who can access remotely from outside the NASA center. In order to obtain organizational approval for secured remote access, the IPG infrastructure needs to be adapted to work with the NASA business process. Improvements need to be made before the IPG can be used for NASA program and mission development. The Secured Advanced Federated Environment (SAFE) technology is designed to provide federated security across NASA center and NASA partner's security domains. Instead of one giant center firewall which can be difficult to modify for different GRID applications, the SAFE "micro security domain" provide large number of professionally managed "micro firewalls" that can allow NASA centers to accept remote IPG access without the worry of damaging other center resources. The SAFE policy-driven capability-based federated security mechanism can enable joint organizational and resource owner approved remote

  15. Immersed boundary lattice Boltzmann model based on multiple relaxation times

    NASA Astrophysics Data System (ADS)

    Lu, Jianhua; Han, Haifeng; Shi, Baochang; Guo, Zhaoli

    2012-01-01

    As an alterative version of the lattice Boltzmann models, the multiple relaxation time (MRT) lattice Boltzmann model introduces much less numerical boundary slip than the single relaxation time (SRT) lattice Boltzmann model if some special relationship between the relaxation time parameters is chosen. On the other hand, most current versions of the immersed boundary lattice Boltzmann method, which was first introduced by Feng and improved by many other authors, suffer from numerical boundary slip as has been investigated by Le and Zhang. To reduce such a numerical boundary slip, an immerse boundary lattice Boltzmann model based on multiple relaxation times is proposed in this paper. A special formula is given between two relaxation time parameters in the model. A rigorous analysis and the numerical experiments carried out show that the numerical boundary slip reduces dramatically by using the present model compared to the single-relaxation-time-based model.

  16. Stage boundary recognition in the Eastern Americas realm based on rugose corals

    USGS Publications Warehouse

    Oliver, W.A.

    2000-01-01

    Most Devonian stages contain characteristic coral assemblages but these tend to be geographically and facies limited and may or may not be useful for recognising stage boundaries. Within eastern North America, corals contribute to the recognition of two boundaries: the base of the Lochkovian (Silurian-Devonian boundary) and the base of the Eifelian (Lower-Middle Devonian Series boundary).

  17. Contaminant Boundary at the Faultless Underground Nuclear Test

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

    Greg Pohll; Karl Pohlmann; Jeff Daniels

    The U.S. Department of Energy (DOE) and the Nevada Division of Environmental Protection (NDEP) have reached agreement on a corrective action strategy applicable to address the extent and potential impact of radionuclide contamination of groundwater at underground nuclear test locations. This strategy is described in detail in the Federal Facility Agreement and Consent Order (FFACO, 2000). As part of the corrective action strategy, the nuclear detonations that occurred underground were identified as geographically distinct corrective action units (CAUs). The strategic objective for each CAU is to estimate over a 1,000-yr time period, with uncertainty quantified, the three-dimensional extent of groundwatermore » contamination that would be considered unsafe for domestic and municipal use. Two types of boundaries (contaminant and compliance) are discussed in the FFACO that will map the three-dimensional extent of radionuclide contamination. The contaminant boundary will identify the region wi th 95 percent certainty that contaminants do not exist above a threshold value. It will be prepared by the DOE and presented to NDEP. The compliance boundary will be produced as a result of negotiation between the DOE and NDEP, and can be coincident with, or differ from, the contaminant boundary. Two different thresholds are considered for the contaminant boundary. One is based on the enforceable National Primary Drinking Water Regulations for radionuclides, which were developed as a requirement of the Safe Drinking Water Act. The other is a risk-based threshold considering applicable lifetime excess cancer-risk-based criteria The contaminant boundary for the Faultless underground nuclear test at the Central Nevada Test Area (CNTA) is calculated using a newly developed groundwater flow and radionuclide transport model that incorporates aspects of both the original three-dimensional model (Pohlmann et al., 1999) and the two-dimensional model developed for the Faultless data

  18. Safe semi-supervised learning based on weighted likelihood.

    PubMed

    Kawakita, Masanori; Takeuchi, Jun'ichi

    2014-05-01

    We are interested in developing a safe semi-supervised learning that works in any situation. Semi-supervised learning postulates that n(') unlabeled data are available in addition to n labeled data. However, almost all of the previous semi-supervised methods require additional assumptions (not only unlabeled data) to make improvements on supervised learning. If such assumptions are not met, then the methods possibly perform worse than supervised learning. Sokolovska, Cappé, and Yvon (2008) proposed a semi-supervised method based on a weighted likelihood approach. They proved that this method asymptotically never performs worse than supervised learning (i.e., it is safe) without any assumption. Their method is attractive because it is easy to implement and is potentially general. Moreover, it is deeply related to a certain statistical paradox. However, the method of Sokolovska et al. (2008) assumes a very limited situation, i.e., classification, discrete covariates, n(')→∞ and a maximum likelihood estimator. In this paper, we extend their method by modifying the weight. We prove that our proposal is safe in a significantly wide range of situations as long as n≤n('). Further, we give a geometrical interpretation of the proof of safety through the relationship with the above-mentioned statistical paradox. Finally, we show that the above proposal is asymptotically safe even when n(')

  19. Confronting unknown planetary boundary threats from chemical pollution.

    PubMed

    Persson, Linn M; Breitholtz, Magnus; Cousins, Ian T; de Wit, Cynthia A; MacLeod, Matthew; McLachlan, Michael S

    2013-11-19

    Rockström et al. proposed a set of planetary boundaries that delimitate a "safe operating space for humanity". One of the planetary boundaries is determined by "chemical pollution", however no clear definition was provided. Here, we propose that there is no single chemical pollution planetary boundary, but rather that many planetary boundary issues governed by chemical pollution exist. We identify three conditions that must be simultaneously met for chemical pollution to pose a planetary boundary threat. We then discuss approaches to identify chemicals that could fulfill those conditions, and outline a proactive hazard identification strategy that considers long-range transport and the reversibility of chemical pollution.

  20. Be-safe travel, a web-based geographic application to explore safe-route in an area

    NASA Astrophysics Data System (ADS)

    Utamima, Amalia; Djunaidy, Arif

    2017-08-01

    In large cities in developing countries, the various forms of criminality are often found. For instance, the most prominent crimes in Surabaya, Indonesia is 3C, that is theft with violence (curas), theft by weighting (curat), and motor vehicle theft (curanmor). 3C case most often occurs on the highway and residential areas. Therefore, new entrants in an area should be aware of these kind of crimes. Route Planners System or route planning system such as Google Maps only consider the shortest distance in the calculation of the optimal route. The selection of the optimal path in this study not only consider the shortest distance, but also involves other factors, namely the security level. This research considers at the need for an application to recommend the safest road to be passed by the vehicle passengers while drive an area. This research propose Be-Safe Travel, a web-based application using Google API that can be accessed by people who like to drive in an area, but still lack of knowledge of the pathways which are safe from crime. Be-Safe Travel is not only useful for the new entrants, but also useful for delivery courier of valuables goods to go through the safest streets.

  1. [Safe school].

    PubMed

    Liberal, Edson Ferreira; Aires, Roberto Tschoepke; Aires, Mariana Tschoepke; Osório, Ana Carla de Albuquerque

    2005-11-01

    To review the strategies to make school a safe environment. The paper first addresses the social context of accidents and violence in the school environment, and makes recommendations, based on the literature data, for the implementation of safe schools. Articles published between 1993 and 2005 in the MEDLINE database. Brazilian epidemiological and literature data have also been searched. There is growing evidence that intervention has multiple components, focusing on health education practices, with the participation of the whole community. The aim of those interventions is to help students and community members to adopt healthy and safe behaviors. Schools are taking on an increasing role in health promotion, disease prevention, and injury prevention. In the context of prevention of external causes of morbidity and mortality, it is important to recognize a risky environment, places, and risk behaviors as favorable to injury and violence, as well as the concept of accident as something one can avoid. Implementation of safe schools represents a promising new direction for school-based preventive work. It is important to note that a safe school should intervene not only in its physical structure, but it should also make it as safe as possible by gathering the school community through health education, and mainly encouraging healthy behavior.

  2. Salient object detection based on discriminative boundary and multiple cues integration

    NASA Astrophysics Data System (ADS)

    Jiang, Qingzhu; Wu, Zemin; Tian, Chang; Liu, Tao; Zeng, Mingyong; Hu, Lei

    2016-01-01

    In recent years, many saliency models have achieved good performance by taking the image boundary as the background prior. However, if all boundaries of an image are equally and artificially selected as background, misjudgment may happen when the object touches the boundary. We propose an algorithm called weighted contrast optimization based on discriminative boundary (wCODB). First, a background estimation model is reliably constructed through discriminating each boundary via Hausdorff distance. Second, the background-only weighted contrast is improved by fore-background weighted contrast, which is optimized through weight-adjustable optimization framework. Then to objectively estimate the quality of a saliency map, a simple but effective metric called spatial distribution of saliency map and mean saliency in covered window ratio (MSR) is designed. Finally, in order to further promote the detection result using MSR as the weight, we propose a saliency fusion framework to integrate three other cues-uniqueness, distribution, and coherence from three representative methods into our wCODB model. Extensive experiments on six public datasets demonstrate that our wCODB performs favorably against most of the methods based on boundary, and the integrated result outperforms all state-of-the-art methods.

  3. Online Dectection and Modeling of Safety Boundaries for Aerospace Application Using Bayesian Statistics

    NASA Technical Reports Server (NTRS)

    He, Yuning

    2015-01-01

    The behavior of complex aerospace systems is governed by numerous parameters. For safety analysis it is important to understand how the system behaves with respect to these parameter values. In particular, understanding the boundaries between safe and unsafe regions is of major importance. In this paper, we describe a hierarchical Bayesian statistical modeling approach for the online detection and characterization of such boundaries. Our method for classification with active learning uses a particle filter-based model and a boundary-aware metric for best performance. From a library of candidate shapes incorporated with domain expert knowledge, the location and parameters of the boundaries are estimated using advanced Bayesian modeling techniques. The results of our boundary analysis are then provided in a form understandable by the domain expert. We illustrate our approach using a simulation model of a NASA neuro-adaptive flight control system, as well as a system for the detection of separation violations in the terminal airspace.

  4. Let the Right One In: Ethnic Boundaries in a Colombian Immigrant Youth Program

    ERIC Educational Resources Information Center

    Pineda, Claudia G.

    2017-01-01

    Although research on minority youth has established the value of coethnic spaces for safe ethnic identity exploration, research has seldom examined how youth in these spaces draw ethnic boundaries or offered appropriate frameworks addressing boundary-setting. This study uses Berry's acculturation framework to explore ethnic boundary-setting within…

  5. Iterations of the SafeCare Model: An Evidence-Based Child Maltreatment Prevention Program

    ERIC Educational Resources Information Center

    Edwards, Anna; Lutzker, John R.

    2008-01-01

    SafeCare is an evidenced-based parenting program for at-risk and maltreating parents that addresses the social and family ecology in which child maltreatment occurs. SafeCare home visitors focus on behavioral skills that are trained to predetermined performance criteria. Recent research has stressed the importance of successful dissemination and…

  6. Safe and Secure Services Based on NGN

    NASA Astrophysics Data System (ADS)

    Fukazawa, Tomoo; Nisase, Takemi; Kawashima, Masahisa; Hariu, Takeo; Oshima, Yoshihito

    Next Generation Network (NGN), which has been undergoing standardization as it has developed, is expected to create new services that converge the fixed and mobile networks. This paper introduces the basic requirements for NGN in terms of security and explains the standardization activities, in particular, the requirements for the security function described in Y.2701 discussed in ITU-T SG-13. In addition to the basic NGN security function, requirements for NGN authentication are also described from three aspects: security, deployability, and service. As examples of authentication implementation, three profiles-namely, fixed, nomadic, and mobile-are defined in this paper. That is, the “fixed profile” is typically for fixed-line subscribers, the “nomadic profile” basically utilizes WiFi access points, and the “mobile profile” provides ideal NGN mobility for mobile subscribers. All three of these profiles satisfy the requirements from security aspects. The three profiles are compared from the viewpoint of requirements for deployability and service. After showing that none of the three profiles can fulfill all of the requirements, we propose that multiple profiles should be used by NGN providers. As service and application examples, two promising NGN applications are proposed. The first is a strong authentication mechanism that makes Web applications more safe and secure even against password theft. It is based on NGN ID federation function. The second provides an easy peer-to-peer broadband virtual private network service aimed at safe and secure communication for personal/SOHO (small office, home office) users, based on NGN SIP (session initiation protocol) session control.

  7. Automatic discrimination between safe and unsafe swallowing using a reputation-based classifier

    PubMed Central

    2011-01-01

    Background Swallowing accelerometry has been suggested as a potential non-invasive tool for bedside dysphagia screening. Various vibratory signal features and complementary measurement modalities have been put forth in the literature for the potential discrimination between safe and unsafe swallowing. To date, automatic classification of swallowing accelerometry has exclusively involved a single-axis of vibration although a second axis is known to contain additional information about the nature of the swallow. Furthermore, the only published attempt at automatic classification in adult patients has been based on a small sample of swallowing vibrations. Methods In this paper, a large corpus of dual-axis accelerometric signals were collected from 30 older adults (aged 65.47 ± 13.4 years, 15 male) referred to videofluoroscopic examination on the suspicion of dysphagia. We invoked a reputation-based classifier combination to automatically categorize the dual-axis accelerometric signals into safe and unsafe swallows, as labeled via videofluoroscopic review. From these participants, a total of 224 swallowing samples were obtained, 164 of which were labeled as unsafe swallows (swallows where the bolus entered the airway) and 60 as safe swallows. Three separate support vector machine (SVM) classifiers and eight different features were selected for classification. Results With selected time, frequency and information theoretic features, the reputation-based algorithm distinguished between safe and unsafe swallowing with promising accuracy (80.48 ± 5.0%), high sensitivity (97.1 ± 2%) and modest specificity (64 ± 8.8%). Interpretation of the most discriminatory features revealed that in general, unsafe swallows had lower mean vibration amplitude and faster autocorrelation decay, suggestive of decreased hyoid excursion and compromised coordination, respectively. Further, owing to its performance-based weighting of component classifiers, the static reputation-based

  8. Has land use pushed terrestrial biodiversity beyond the planetary boundary? A global assessment.

    PubMed

    Newbold, Tim; Hudson, Lawrence N; Arnell, Andrew P; Contu, Sara; De Palma, Adriana; Ferrier, Simon; Hill, Samantha L L; Hoskins, Andrew J; Lysenko, Igor; Phillips, Helen R P; Burton, Victoria J; Chng, Charlotte W T; Emerson, Susan; Gao, Di; Pask-Hale, Gwilym; Hutton, Jon; Jung, Martin; Sanchez-Ortiz, Katia; Simmons, Benno I; Whitmee, Sarah; Zhang, Hanbin; Scharlemann, Jörn P W; Purvis, Andy

    2016-07-15

    Land use and related pressures have reduced local terrestrial biodiversity, but it is unclear how the magnitude of change relates to the recently proposed planetary boundary ("safe limit"). We estimate that land use and related pressures have already reduced local biodiversity intactness--the average proportion of natural biodiversity remaining in local ecosystems--beyond its recently proposed planetary boundary across 58.1% of the world's land surface, where 71.4% of the human population live. Biodiversity intactness within most biomes (especially grassland biomes), most biodiversity hotspots, and even some wilderness areas is inferred to be beyond the boundary. Such widespread transgression of safe limits suggests that biodiversity loss, if unchecked, will undermine efforts toward long-term sustainable development. Copyright © 2016, American Association for the Advancement of Science.

  9. Bayesian Statistics and Uncertainty Quantification for Safety Boundary Analysis in Complex Systems

    NASA Technical Reports Server (NTRS)

    He, Yuning; Davies, Misty Dawn

    2014-01-01

    The analysis of a safety-critical system often requires detailed knowledge of safe regions and their highdimensional non-linear boundaries. We present a statistical approach to iteratively detect and characterize the boundaries, which are provided as parameterized shape candidates. Using methods from uncertainty quantification and active learning, we incrementally construct a statistical model from only few simulation runs and obtain statistically sound estimates of the shape parameters for safety boundaries.

  10. Brain-Based Learning and Educational Neuroscience: Boundary Work

    ERIC Educational Resources Information Center

    Edelenbosch, Rosanne; Kupper, Frank; Krabbendam, Lydia; Broerse, Jacqueline E. W.

    2015-01-01

    Much attention has been given to "bridging the gap" between neuroscience and educational practice. In order to gain better understanding of the nature of this gap and of possibilities to enable the linking process, we have taken a boundary perspective on these two fields and the brain-based learning approach, focusing on…

  11. Safe medication management in specialized home healthcare - an observational study.

    PubMed

    Lindblad, Marléne; Flink, Maria; Ekstedt, Mirjam

    2017-08-24

    Medication management is a complex, error-prone process. The aim of this study was to explore what constitutes the complexity of the medication management process (MMP) in specialized home healthcare and how healthcare professionals handle this complexity. The study is theoretically based in resilience engineering. Data were collected during the MMP at three specialized home healthcare units in Sweden using two strategies: observation of workplaces and shadowing RNs in everyday work, including interviews. Transcribed material was analysed using grounded theory. The MMP in home healthcare was dynamic and complex with unclear boundaries of responsibilities, inadequate information systems and fluctuating work conditions. Healthcare professionals adapted their everyday clinical work by sharing responsibility and simultaneously being authoritative and preserving patients' active participation, autonomy and integrity. To promote a safe MMP, healthcare professionals constantly re-prioritized goals, handled gaps in communication and information transmission at a distance by creating new bridging solutions. Trade-offs and workarounds were necessary elements, but also posed a threat to patient safety, as these interim solutions were not systematically evaluated or devised learning strategies. To manage a safe medication process in home healthcare, healthcare professionals need to adapt to fluctuating conditions and create bridging strategies through multiple parallel activities distributed over time, space and actors. The healthcare professionals' strategies could be integrated in continuous learning, while preserving boundaries of safety, instead of being more or less interim solutions. Patients' and family caregivers' as active partners in the MMP may be an underestimated resource for a resilient home healthcare.

  12. Preconditioned characteristic boundary conditions based on artificial compressibility method for solution of incompressible flows

    NASA Astrophysics Data System (ADS)

    Hejranfar, Kazem; Parseh, Kaveh

    2017-09-01

    The preconditioned characteristic boundary conditions based on the artificial compressibility (AC) method are implemented at artificial boundaries for the solution of two- and three-dimensional incompressible viscous flows in the generalized curvilinear coordinates. The compatibility equations and the corresponding characteristic variables (or the Riemann invariants) are mathematically derived and then applied as suitable boundary conditions in a high-order accurate incompressible flow solver. The spatial discretization of the resulting system of equations is carried out by the fourth-order compact finite-difference (FD) scheme. In the preconditioning applied here, the value of AC parameter in the flow field and also at the far-field boundary is automatically calculated based on the local flow conditions to enhance the robustness and performance of the solution algorithm. The code is fully parallelized using the Concurrency Runtime standard and Parallel Patterns Library (PPL) and its performance on a multi-core CPU is analyzed. The incompressible viscous flows around a 2-D circular cylinder, a 2-D NACA0012 airfoil and also a 3-D wavy cylinder are simulated and the accuracy and performance of the preconditioned characteristic boundary conditions applied at the far-field boundaries are evaluated in comparison to the simplified boundary conditions and the non-preconditioned characteristic boundary conditions. It is indicated that the preconditioned characteristic boundary conditions considerably improve the convergence rate of the solution of incompressible flows compared to the other boundary conditions and the computational costs are significantly decreased.

  13. Mechanisms of behavioural maintenance: Long-term effects of theory-based interventions to promote safe water consumption.

    PubMed

    Inauen, Jennifer; Mosler, Hans-Joachim

    2016-01-01

    Theory-based interventions can enhance people's safe water consumption, but the sustainability of these interventions and the mechanisms of maintenance remain unclear. We investigated these questions based on an extended theory of planned behaviour. Seven hundred and ten (445 analysed) randomly selected households participated in two cluster-randomised controlled trials in Bangladesh. Study 1 promoted switching to neighbours' arsenic-safe wells, and Study 2 promoted switching to arsenic-safe deep wells. Both studies included two intervention phases. Structured interviews were conducted at baseline (T1), and at 1-month (T2), 2-month (T3) and 9-month (T4) follow-ups. In intervention phase 1 (between T1 and T2), commitment-based behaviour change techniques--reminders, implementation intentions and public commitment--were combined with information and compared to an information-only control group. In phase 2 (between T2 and T3), half of each phase 1 intervention group was randomly assigned to receive either commitment-based techniques once more or coping planning with reminders and information. Initial well-switching rates of up to 60% significantly declined by T4: 38.3% of T2 safe water users stopped consuming arsenic-safe water. The decline depended on the intervention. Perceived behavioural control, intentions, commitment strength and coping planning were associated with maintenance. In line with previous studies, the results indicate that commitment and reminders engender long-term behavioural change.

  14. Safe lithium-ion battery with ionic liquid-based electrolyte for hybrid electric vehicles

    NASA Astrophysics Data System (ADS)

    Damen, Libero; Lazzari, Mariachiara; Mastragostino, Marina

    2011-10-01

    A lithium-ion battery featuring graphite anode, LiFePO4-C cathode and an innovative, safe, ionic liquid-based electrolyte, was assembled and characterized in terms of specific energy and power after the USABC-DOE protocol for power-assist hybrid electric vehicle (HEV) application. The test results show that the battery surpasses the energy and power goals stated by USABC-DOE and, hence, this safe lithium-ion battery should be suitable for application in the evolving HEV market.

  15. Measurements of strain at plate boundaries using space based geodetic techniques

    NASA Technical Reports Server (NTRS)

    Robaudo, Stefano; Harrison, Christopher G. A.

    1993-01-01

    We have used the space based geodetic techniques of Satellite Laser Ranging (SLR) and VLBI to study strain along subduction and transform plate boundaries and have interpreted the results using a simple elastic dislocation model. Six stations located behind island arcs were analyzed as representative of subduction zones while 13 sites located on either side of the San Andreas fault were used for the transcurrent zones. The length deformation scale was then calculated for both tectonic margins by fitting the relative strain to an exponentially decreasing function of distance from the plate boundary. Results show that space-based data for the transcurrent boundary along the San Andreas fault help to define better the deformation length scale in the area while fitting nicely the elastic half-space earth model. For subduction type bonndaries the analysis indicates that there is no single scale length which uniquely describes the deformation. This is mainly due to the difference in subduction characteristics for the different areas.

  16. Algorithm based on regional separation for automatic grain boundary extraction using improved mean shift method

    NASA Astrophysics Data System (ADS)

    Zhenying, Xu; Jiandong, Zhu; Qi, Zhang; Yamba, Philip

    2018-06-01

    Metallographic microscopy shows that the vast majority of metal materials are composed of many small grains; the grain size of a metal is important for determining the tensile strength, toughness, plasticity, and other mechanical properties. In order to quantitatively evaluate grain size in metals, grain boundaries must be identified in metallographic images. Based on the phenomenon of grain boundary blurring or disconnection in metallographic images, this study develops an algorithm based on regional separation for automatically extracting grain boundaries by an improved mean shift method. Experimental observation shows that the grain boundaries obtained by the proposed algorithm are highly complete and accurate. This research has practical value because the proposed algorithm is suitable for grain boundary extraction from most metallographic images.

  17. Plasma-based actuators for turbulent boundary layer control in transonic flow

    NASA Astrophysics Data System (ADS)

    Budovsky, A. D.; Polivanov, P. A.; Vishnyakov, O. I.; Sidorenko, A. A.

    2017-10-01

    The study is devoted to development of methods for active control of flow structure typical for the aircraft wings in transonic flow with turbulent boundary layer. The control strategy accepted in the study was based on using of the effects of plasma discharges interaction with miniature geometrical obstacles of various shapes. The conceptions were studied computationally using 3D RANS, URANS approaches. The results of the computations have shown that energy deposition can significantly change the flow pattern over the obstacles increasing their influence on the flow in boundary layer region. Namely, one of the most interesting and promising data were obtained for actuators basing on combination of vertical wedge with asymmetrical plasma discharge. The wedge considered is aligned with the local streamlines and protruding in the flow by 0.4-0.8 of local boundary layer thickness. The actuator produces negligible distortion of the flow at the absence of energy deposition. Energy deposition along the one side of the wedge results in longitudinal vortex formation in the wake of the actuator providing momentum exchange in the boundary layer. The actuator was manufactured and tested in wind tunnel experiments at Mach number 1.5 using the model of flat plate. The experimental data obtained by PIV proved the availability of the actuator.

  18. Operationalizing safe operating space for regional social-ecological systems.

    PubMed

    Hossain, Md Sarwar; Dearing, John A; Eigenbrod, Felix; Johnson, Fiifi Amoako

    2017-04-15

    This study makes a first attempt to operationalize the safe operating space concept at a regional scale by considering the complex dynamics (e.g. non-linearity, feedbacks, and interactions) within a systems dynamic model (SD). We employ the model to explore eight 'what if' scenarios based on well-known challenges (e.g. climate change) and current policy debates (e.g. subsidy withdrawal). The findings show that the social-ecological system in the Bangladesh delta may move beyond a safe operating space when a withdrawal of a 50% subsidy for agriculture is combined with the effects of a 2°C temperature increase and sea level rise. Further reductions in upstream river discharge in the Ganges would push the system towards a dangerous zone once a 3.5°C temperature increase was reached. The social-ecological system in Bangladesh delta may be operated within a safe space by: 1) managing feedback (e.g. by reducing production costs) and the slow biophysical variables (e.g. temperature, rainfall) to increase the long-term resilience, 2) negotiating for transboundary water resources, and 3) revising global policies (e.g. withdrawal of subsidy) that negatively impact at regional scales. This study demonstrates how the concepts of tipping points, limits to adaptations, and boundaries for sustainable development may be defined in real world social-ecological systems. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  19. Boundary Layer Observations of Water Vapor and Aerosol Profiles with an Eye-Safe Micro-Pulse Differential Absorption Lidar (DIAL)

    NASA Astrophysics Data System (ADS)

    Nehrir, A. R.; Repasky, K. S.; Carlsten, J.; Ismail, S.

    2011-12-01

    Measurements of real-time high spatial and temporal resolution profiles of combined water vapor and aerosols in the boundary layer have been a long standing observational challenge to the meteorological, weather forecasting, and climate science communities. To overcome the high reoccurring costs associated with radiosondes as well as the lack of sufficient water vapor measurements over the continental united states, a compact and low cost eye-safe all semiconductor-based micro-pulse differential absorption lidar (DIAL) has been developed for water vapor and aerosol profiling in the lower troposphere. The laser transmitter utilizes two continuous wave external cavity diode lasers operating in the 830 nm absorption band as the online and offline seed laser sources. An optical switch is used to sequentially injection seed a tapered semiconductor optical amplifier (TSOA) with the two seed laser sources in a master oscillator power amplifier (MOPA) configuration. The TSOA is actively current pulsed to produce up to 7 μJ of output energy over a 1 μs pulse duration (150 m vertical resolution) at a 10 kHz pulse repetition frequency. The measured laser transmitter spectral linewidth is less than 500 kHz while the long term frequency stability of the stabilized on-line wavelength is ± 55 MHz. The laser transmitter spectral purity was measured to be greater than 0.9996, allowing for simultaneous measurements of water vapor in the lower and upper troposphere. The DIAL receiver utilizes a commercially available full sky-scanning capable 35 cm Schmidt-Cassegrain telescope to collect the scattered light from the laser transmitter. Light collected by the telescope is spectrally filtered to suppress background noise and is coupled into a fiber optic cable which acts as the system field stop and limits the full angle field of view to 140 μrad. The light is sampled by a fiber coupled APD operated in a Geiger mode. The DIAL instrument is operated autonomously where water vapor and

  20. Safe Maneuvering Envelope Estimation Based on a Physical Approach

    NASA Technical Reports Server (NTRS)

    Lombaerts, Thomas J. J.; Schuet, Stefan R.; Wheeler, Kevin R.; Acosta, Diana; Kaneshige, John T.

    2013-01-01

    This paper discusses a computationally efficient algorithm for estimating the safe maneuvering envelope of damaged aircraft. The algorithm performs a robust reachability analysis through an optimal control formulation while making use of time scale separation and taking into account uncertainties in the aerodynamic derivatives. This approach differs from others since it is physically inspired. This more transparent approach allows interpreting data in each step, and it is assumed that these physical models based upon flight dynamics theory will therefore facilitate certification for future real life applications.

  1. Boundary-based cellwise OPC for standard-cell layouts

    NASA Astrophysics Data System (ADS)

    Pawlowski, David M.; Deng, Liang; Wong, Martin D. F.

    2007-03-01

    Model based optical proximity correction (OPC) has become necessary at 90nm technology node. Cellwise OPC is an attractive technique to reduce the mask data size as well as the prohibitive runtime of full-chip OPC. As feature dimensions have gotten smaller, the radius of influence for edge features has extended further into neighboring cells such that it is no longer sufficient to perform cellwise OPC independent of neighboring cells, especially for the critical layers. The methodology described in this work accounts for features in neighboring cells and allows a cellwise approach to be applied to cells with a printed gate length of 45nm with the projection that it can also be applied to future technology nodes. OPC-ready cells are generated at library creation (independent of placement) using a boundary-based technique. Each cell has a tractable number of OPC-ready versions due to an intelligent characterization of standard cell layout features. Results are very promising: the average edge placement error (EPE) for all metal1 features in 100 layouts is 0.731nm which is less than 1% of metal1 width; the maximum EPE for poly features reduced to 1/3, compared to cellwise OPC without considering boundaries, creating similar levels of lithographic accuracy while obviating any of the drawbacks inherent in layout specific full-chip model-based OPC.

  2. Artificial Boundary Conditions Based on the Difference Potentials Method

    NASA Technical Reports Server (NTRS)

    Tsynkov, Semyon V.

    1996-01-01

    While numerically solving a problem initially formulated on an unbounded domain, one typically truncates this domain, which necessitates setting the artificial boundary conditions (ABC's) at the newly formed external boundary. The issue of setting the ABC's appears to be most significant in many areas of scientific computing, for example, in problems originating from acoustics, electrodynamics, solid mechanics, and fluid dynamics. In particular, in computational fluid dynamics (where external problems present a wide class of practically important formulations) the proper treatment of external boundaries may have a profound impact on the overall quality and performance of numerical algorithms. Most of the currently used techniques for setting the ABC's can basically be classified into two groups. The methods from the first group (global ABC's) usually provide high accuracy and robustness of the numerical procedure but often appear to be fairly cumbersome and (computationally) expensive. The methods from the second group (local ABC's) are, as a rule, algorithmically simple, numerically cheap, and geometrically universal; however, they usually lack accuracy of computations. In this paper we first present a survey and provide a comparative assessment of different existing methods for constructing the ABC's. Then, we describe a relatively new ABC's technique of ours and review the corresponding results. This new technique, in our opinion, is currently one of the most promising in the field. It enables one to construct such ABC's that combine the advantages relevant to the two aforementioned classes of existing methods. Our approach is based on application of the difference potentials method attributable to V. S. Ryaben'kii. This approach allows us to obtain highly accurate ABC's in the form of certain (nonlocal) boundary operator equations. The operators involved are analogous to the pseudodifferential boundary projections first introduced by A. P. Calderon and then

  3. Sensitivity of boundary-layer stability to base-state distortions at high Mach numbers

    NASA Astrophysics Data System (ADS)

    Park, Junho; Zaki, Tamer

    2017-11-01

    The stability diagram of high-speed boundary layers has been established by evaluating the linear instability modes of the similarity profile, over wide ranges of Reynolds and Mach numbers. In real flows, however, the base state can deviate from the similarity profile. Both the base velocity and temperature can be distorted, for example due to roughness and thermal wall treatments. We review the stability problem of high-speed boundary layer, and derive a new formulation of the sensitivity to base-state distortion using forward and adjoint parabolized stability equations. The new formulation provides qualitative and quantitative interpretations on change in growth rate due to modifications of mean-flow and mean-temperature in heated high-speed boundary layers, and establishes the foundation for future control strategies. This work has been funded by the Air Force Office of Scientific Research (AFOSR) Grant: FA9550-16-1-0103.

  4. SOME PROBLEMS OF "SAFE DOSE" ESTIMATION

    EPA Science Inventory

    In environmental carcinogenic risk assessment, the usually defined "safe doses" appear subjective in some sense. n this paper a method of standardizing "safe doses" based on some objective parameters is introduced and a procedure of estimating safe doses under the competing risks...

  5. Overview of Boundary Layer Clouds Using Satellite and Ground-Based Measurements

    NASA Astrophysics Data System (ADS)

    Xi, B.; Dong, X.; Wu, P.; Qiu, S.

    2017-12-01

    A comprehensive summary of boundary layer clouds properties based on our few recently studies will be presented. The analyses include the global cloud fractions and cloud macro/micro- physical properties based on satellite measurements using both CERES-MODIS and CloudSat/Caliposo data products,; the annual/seasonal/diurnal variations of stratocumulus clouds over different climate regions (mid-latitude land, mid-latitude ocean, and Arctic region) using DOE ARM ground-based measurements over Southern great plain (SGP), Azores (GRW), and North slope of Alaska (NSA) sites; the impact of environmental conditions to the formation and dissipation process of marine boundary layer clouds over Azores site; characterizing Arctice mixed-phase cloud structure and favorable environmental conditions for the formation/maintainess of mixed-phase clouds over NSA site. Though the presentation has widely spread topics, we will focus on the representation of the ground-based measurements over different climate regions; evaluation of satellite retrieved cloud properties using these ground-based measurements, and understanding the uncertainties of both satellite and ground-based retrievals and measurements.

  6. Efficient Boundary Extraction of BSP Solids Based on Clipping Operations.

    PubMed

    Wang, Charlie C L; Manocha, Dinesh

    2013-01-01

    We present an efficient algorithm to extract the manifold surface that approximates the boundary of a solid represented by a Binary Space Partition (BSP) tree. Our polygonization algorithm repeatedly performs clipping operations on volumetric cells that correspond to a spatial convex partition and computes the boundary by traversing the connected cells. We use point-based representations along with finite-precision arithmetic to improve the efficiency and generate the B-rep approximation of a BSP solid. The core of our polygonization method is a novel clipping algorithm that uses a set of logical operations to make it resistant to degeneracies resulting from limited precision of floating-point arithmetic. The overall BSP to B-rep conversion algorithm can accurately generate boundaries with sharp and small features, and is faster than prior methods. At the end of this paper, we use this algorithm for a few geometric processing applications including Boolean operations, model repair, and mesh reconstruction.

  7. Measuring grain boundary character distributions in Ni-base alloy 725 using high-energy diffraction microscopy

    DOE PAGES

    Bagri, Akbar; Hanson, John P.; Lind, J. P.; ...

    2016-10-25

    We use high-energy X-ray diffraction microscopy (HEDM) to characterize the microstructure of Ni-base alloy 725. HEDM is a non-destructive technique capable of providing three-dimensional reconstructions of grain shapes and orientations in polycrystals. The present analysis yields the grain size distribution in alloy 725 as well as the grain boundary character distribution (GBCD) as a function of lattice misorientation and boundary plane normal orientation. We find that the GBCD of Ni-base alloy 725 is similar to that previously determined in pure Ni and other fcc-base metals. We find an elevated density of Σ9 and Σ3 grain boundaries. We also observe amore » preponderance of grain boundaries along low-index planes, with those along (1 1 1) planes being the most common, even after Σ3 twins have been excluded from the analysis.« less

  8. Superpixel-based and boundary-sensitive convolutional neural network for automated liver segmentation

    NASA Astrophysics Data System (ADS)

    Qin, Wenjian; Wu, Jia; Han, Fei; Yuan, Yixuan; Zhao, Wei; Ibragimov, Bulat; Gu, Jia; Xing, Lei

    2018-05-01

    Segmentation of liver in abdominal computed tomography (CT) is an important step for radiation therapy planning of hepatocellular carcinoma. Practically, a fully automatic segmentation of liver remains challenging because of low soft tissue contrast between liver and its surrounding organs, and its highly deformable shape. The purpose of this work is to develop a novel superpixel-based and boundary sensitive convolutional neural network (SBBS-CNN) pipeline for automated liver segmentation. The entire CT images were first partitioned into superpixel regions, where nearby pixels with similar CT number were aggregated. Secondly, we converted the conventional binary segmentation into a multinomial classification by labeling the superpixels into three classes: interior liver, liver boundary, and non-liver background. By doing this, the boundary region of the liver was explicitly identified and highlighted for the subsequent classification. Thirdly, we computed an entropy-based saliency map for each CT volume, and leveraged this map to guide the sampling of image patches over the superpixels. In this way, more patches were extracted from informative regions (e.g. the liver boundary with irregular changes) and fewer patches were extracted from homogeneous regions. Finally, deep CNN pipeline was built and trained to predict the probability map of the liver boundary. We tested the proposed algorithm in a cohort of 100 patients. With 10-fold cross validation, the SBBS-CNN achieved mean Dice similarity coefficients of 97.31  ±  0.36% and average symmetric surface distance of 1.77  ±  0.49 mm. Moreover, it showed superior performance in comparison with state-of-art methods, including U-Net, pixel-based CNN, active contour, level-sets and graph-cut algorithms. SBBS-CNN provides an accurate and effective tool for automated liver segmentation. It is also envisioned that the proposed framework is directly applicable in other medical image segmentation scenarios.

  9. How Safe Are Kid-Safe Search Engines?

    ERIC Educational Resources Information Center

    Masterson-Krum, Hope

    2001-01-01

    Examines search tools available to elementary and secondary school students, both human-compiled and crawler-based, to help direct them to age-appropriate Web sites; analyzes the procedures of search engines labeled family-friendly or kid safe that use filters; and tests the effectiveness of these services to students in school libraries. (LRW)

  10. Geometry-based ensembles: toward a structural characterization of the classification boundary.

    PubMed

    Pujol, Oriol; Masip, David

    2009-06-01

    This paper introduces a novel binary discriminative learning technique based on the approximation of the nonlinear decision boundary by a piecewise linear smooth additive model. The decision border is geometrically defined by means of the characterizing boundary points-points that belong to the optimal boundary under a certain notion of robustness. Based on these points, a set of locally robust linear classifiers is defined and assembled by means of a Tikhonov regularized optimization procedure in an additive model to create a final lambda-smooth decision rule. As a result, a very simple and robust classifier with a strong geometrical meaning and nonlinear behavior is obtained. The simplicity of the method allows its extension to cope with some of today's machine learning challenges, such as online learning, large-scale learning or parallelization, with linear computational complexity. We validate our approach on the UCI database, comparing with several state-of-the-art classification techniques. Finally, we apply our technique in online and large-scale scenarios and in six real-life computer vision and pattern recognition problems: gender recognition based on face images, intravascular ultrasound tissue classification, speed traffic sign detection, Chagas' disease myocardial damage severity detection, old musical scores clef classification, and action recognition using 3D accelerometer data from a wearable device. The results are promising and this paper opens a line of research that deserves further attention.

  11. A novel transferable individual tree crown delineation model based on Fishing Net Dragging and boundary classification

    NASA Astrophysics Data System (ADS)

    Liu, Tao; Im, Jungho; Quackenbush, Lindi J.

    2015-12-01

    This study provides a novel approach to individual tree crown delineation (ITCD) using airborne Light Detection and Ranging (LiDAR) data in dense natural forests using two main steps: crown boundary refinement based on a proposed Fishing Net Dragging (FiND) method, and segment merging based on boundary classification. FiND starts with approximate tree crown boundaries derived using a traditional watershed method with Gaussian filtering and refines these boundaries using an algorithm that mimics how a fisherman drags a fishing net. Random forest machine learning is then used to classify boundary segments into two classes: boundaries between trees and boundaries between branches that belong to a single tree. Three groups of LiDAR-derived features-two from the pseudo waveform generated along with crown boundaries and one from a canopy height model (CHM)-were used in the classification. The proposed ITCD approach was tested using LiDAR data collected over a mountainous region in the Adirondack Park, NY, USA. Overall accuracy of boundary classification was 82.4%. Features derived from the CHM were generally more important in the classification than the features extracted from the pseudo waveform. A comprehensive accuracy assessment scheme for ITCD was also introduced by considering both area of crown overlap and crown centroids. Accuracy assessment using this new scheme shows the proposed ITCD achieved 74% and 78% as overall accuracy, respectively, for deciduous and mixed forest.

  12. A Kp-based model of auroral boundaries

    NASA Astrophysics Data System (ADS)

    Carbary, James F.

    2005-10-01

    The auroral oval can serve as both a representation and a prediction of space weather on a global scale, so a competent model of the oval as a function of a geomagnetic index could conveniently appraise space weather itself. A simple model of the auroral boundaries is constructed by binning several months of images from the Polar Ultraviolet Imager by Kp index. The pixel intensities are first averaged into magnetic latitude-magnetic local time (MLT-MLAT) and local time bins, and intensity profiles are then derived for each Kp level at 1 hour intervals of MLT. After background correction, the boundary latitudes of each profile are determined at a threshold of 4 photons cm-2 s1. The peak locations and peak intensities are also found. The boundary and peak locations vary linearly with Kp index, and the coefficients of the linear fits are tabulated for each MLT. As a general rule of thumb, the UV intensity peak shifts 1° in magnetic latitude for each increment in Kp. The fits are surprisingly good for Kp < 6 but begin to deteriorate at high Kp because of auroral boundary irregularities and poor statistics. The statistical model allows calculation of the auroral boundaries at most MLTs as a function of Kp and can serve as an approximation to the shape and extent of the statistical oval.

  13. A velocity-correction projection method based immersed boundary method for incompressible flows

    NASA Astrophysics Data System (ADS)

    Cai, Shanggui

    2014-11-01

    In the present work we propose a novel direct forcing immersed boundary method based on the velocity-correction projection method of [J.L. Guermond, J. Shen, Velocity-correction projection methods for incompressible flows, SIAM J. Numer. Anal., 41 (1)(2003) 112]. The principal idea of immersed boundary method is to correct the velocity in the vicinity of the immersed object by using an artificial force to mimic the presence of the physical boundaries. Therefore, velocity-correction projection method is preferred to its pressure-correction counterpart in the present work. Since the velocity-correct projection method is considered as a dual class of pressure-correction method, the proposed method here can also be interpreted in the way that first the pressure is predicted by treating the viscous term explicitly without the consideration of the immersed boundary, and the solenoidal velocity is used to determine the volume force on the Lagrangian points, then the non-slip boundary condition is enforced by correcting the velocity with the implicit viscous term. To demonstrate the efficiency and accuracy of the proposed method, several numerical simulations are performed and compared with the results in the literature. China Scholarship Council.

  14. Explicit treatment for Dirichlet, Neumann and Cauchy boundary conditions in POD-based reduction of groundwater models

    NASA Astrophysics Data System (ADS)

    Gosses, Moritz; Nowak, Wolfgang; Wöhling, Thomas

    2018-05-01

    In recent years, proper orthogonal decomposition (POD) has become a popular model reduction method in the field of groundwater modeling. It is used to mitigate the problem of long run times that are often associated with physically-based modeling of natural systems, especially for parameter estimation and uncertainty analysis. POD-based techniques reproduce groundwater head fields sufficiently accurate for a variety of applications. However, no study has investigated how POD techniques affect the accuracy of different boundary conditions found in groundwater models. We show that the current treatment of boundary conditions in POD causes inaccuracies for these boundaries in the reduced models. We provide an improved method that splits the POD projection space into a subspace orthogonal to the boundary conditions and a separate subspace that enforces the boundary conditions. To test the method for Dirichlet, Neumann and Cauchy boundary conditions, four simple transient 1D-groundwater models, as well as a more complex 3D model, are set up and reduced both by standard POD and POD with the new extension. We show that, in contrast to standard POD, the new method satisfies both Dirichlet and Neumann boundary conditions. It can also be applied to Cauchy boundaries, where the flux error of standard POD is reduced by its head-independent contribution. The extension essentially shifts the focus of the projection towards the boundary conditions. Therefore, we see a slight trade-off between errors at model boundaries and overall accuracy of the reduced model. The proposed POD extension is recommended where exact treatment of boundary conditions is required.

  15. Topology optimization analysis based on the direct coupling of the boundary element method and the level set method

    NASA Astrophysics Data System (ADS)

    Vitório, Paulo Cezar; Leonel, Edson Denner

    2017-12-01

    The structural design must ensure suitable working conditions by attending for safe and economic criteria. However, the optimal solution is not easily available, because these conditions depend on the bodies' dimensions, materials strength and structural system configuration. In this regard, topology optimization aims for achieving the optimal structural geometry, i.e. the shape that leads to the minimum requirement of material, respecting constraints related to the stress state at each material point. The present study applies an evolutionary approach for determining the optimal geometry of 2D structures using the coupling of the boundary element method (BEM) and the level set method (LSM). The proposed algorithm consists of mechanical modelling, topology optimization approach and structural reconstruction. The mechanical model is composed of singular and hyper-singular BEM algebraic equations. The topology optimization is performed through the LSM. Internal and external geometries are evolved by the LS function evaluated at its zero level. The reconstruction process concerns the remeshing. Because the structural boundary moves at each iteration, the body's geometry change and, consequently, a new mesh has to be defined. The proposed algorithm, which is based on the direct coupling of such approaches, introduces internal cavities automatically during the optimization process, according to the intensity of Von Mises stress. The developed optimization model was applied in two benchmarks available in the literature. Good agreement was observed among the results, which demonstrates its efficiency and accuracy.

  16. Safe sex

    MedlinePlus

    ... sex; Sexually transmitted - safe sex; GC - safe sex; Gonorrhea - safe sex; Herpes - safe sex; HIV - safe sex; ... contact. STIs include: Chlamydia Genital herpes Genital warts Gonorrhea Hepatitis HIV HPV Syphilis STIs are also called ...

  17. Safe Schools, Safe Students. Proceedings of the National Education Goals Panel/National Alliance of Pupil Services Organizations Conference on "Safe Schools, Safe Students: A Collaborative Approach to Achieving Safe, Disciplined, and Drug-free Schools Conducive to Learning" (Washington, D.C., October 28-29, 1994).

    ERIC Educational Resources Information Center

    Talley, Ronda C., Ed.; Walz, Garry R., Ed.

    The "Safe Schools, Safe Students" conference brought together leading researchers and practitioners in order to share knowledge about innovative safety strategies being used in America's schools. The papers here represent the thinking of scientific experts and school-based pupil service providers who are implementing programs to prevent…

  18. Boundary Engineering for the Thermoelectric Performance of Bulk Alloys Based on Bismuth Telluride.

    PubMed

    Mun, Hyeona; Choi, Soon-Mok; Lee, Kyu Hyoung; Kim, Sung Wng

    2015-07-20

    Thermoelectrics, which transports heat for refrigeration or converts heat into electricity directly, is a key technology for renewable energy harvesting and solid-state refrigeration. Despite its importance, the widespread use of thermoelectric devices is constrained because of the low efficiency of thermoelectric bulk alloys. However, boundary engineering has been demonstrated as one of the most effective ways to enhance the thermoelectric performance of conventional thermoelectric materials such as Bi2 Te3 , PbTe, and SiGe alloys because their thermal and electronic transport properties can be manipulated separately by this approach. We review our recent progress on the enhancement of the thermoelectric figure of merit through boundary engineering together with the processing technologies for boundary engineering developed most recently using Bi2 Te3 -based bulk alloys. A brief discussion of the principles and current status of boundary-engineered bulk alloys for the enhancement of the thermoelectric figure of merit is presented. We focus mainly on (1) the reduction of the thermal conductivity by grain boundary engineering and (2) the reduction of thermal conductivity without deterioration of the electrical conductivity by phase boundary engineering. We also discuss the next potential approach using two boundary engineering strategies for a breakthrough in the area of bulk thermoelectric alloys. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Equivalence-point electromigration acid-base titration via moving neutralization boundary electrophoresis.

    PubMed

    Yang, Qing; Fan, Liu-Yin; Huang, Shan-Sheng; Zhang, Wei; Cao, Cheng-Xi

    2011-04-01

    In this paper, we developed a novel method of acid-base titration, viz. the electromigration acid-base titration (EABT), via a moving neutralization boundary (MNR). With HCl and NaOH as the model strong acid and base, respectively, we conducted the experiments on the EABT via the method of moving neutralization boundary for the first time. The experiments revealed that (i) the concentration of agarose gel, the voltage used and the content of background electrolyte (KCl) had evident influence on the boundary movement; (ii) the movement length was a function of the running time under the constant acid and base concentrations; and (iii) there was a good linearity between the length and natural logarithmic concentration of HCl under the optimized conditions, and the linearity could be used to detect the concentration of acid. The experiments further manifested that (i) the RSD values of intra-day and inter-day runs were less than 1.59 and 3.76%, respectively, indicating similar precision and stability in capillary electrophoresis or HPLC; (ii) the indicators with different pK(a) values had no obvious effect on EABT, distinguishing strong influence on the judgment of equivalence-point titration in the classic one; and (iii) the constant equivalence-point titration always existed in the EABT, rather than the classic volumetric analysis. Additionally, the EABT could be put to good use for the determination of actual acid concentrations. The experimental results achieved herein showed a new general guidance for the development of classic volumetric analysis and element (e.g. nitrogen) content analysis in protein chemistry. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Prediction of safe driving Behaviours based on health belief model: the case of taxi drivers in Bandar Abbas, Iran.

    PubMed

    Razmara, Asghar; Aghamolaei, Teamur; Madani, Abdoulhossain; Hosseini, Zahra; Zare, Shahram

    2018-03-20

    Road accidents are among the main causes of mortality. As safe and secure driving is a key strategy to reduce car injuries and offenses, the present research aimed to explore safe driving behaviours among taxi drivers based on the Health Belief Model (HBM). This study was conducted on 184 taxi drivers in Bandar Abbas who were selected based on a multiple stratified sampling method. Data were collected by a questionnaire comprised of a demographic information section along with the constructs of the HBM. Data were analysed by SPSS ver19 via a Pearson's correlation coefficient and multiple regressions. The mean age of the participants was 45.1 years (SD = 11.1). They all had, on average, 10.3 (SD = 7/5) years of taxi driving experience. Among the HBM components, cues to action and perceived benefits were shown to be positively correlated with safe driving behaviours, while perceived barriers were negatively correlated. Cues to action, perceived barriers and perceived benefits were shown to be the strongest predictors of a safe drivers' behaviour. Based on the results of this study in designing health promotion programmes to improve safe driving behaviours among taxi drivers, cues to action, perceived benefits and perceived barriers are important. Therefore, advertising, the design of information campaigns, emphasis on the benefits of safe driving behaviours and modification barriers are recommended.

  1. The effects of the evidence-based Safe Dates dating abuse prevention program on other youth violence outcomes.

    PubMed

    Foshee, Vangie A; Reyes, Luz McNaughton; Agnew-Brune, Christine B; Simon, Thomas R; Vagi, Kevin J; Lee, Rosalyn D; Suchindran, Chiravath

    2014-12-01

    In response to recent calls for programs that can prevent multiple types of youth violence, the current study examined whether Safe Dates, an evidence-based dating violence prevention program, was effective in preventing other forms of youth violence. Using data from the original Safe Dates randomized controlled trial, this study examined (1) the effectiveness of Safe Dates in preventing peer violence victimization and perpetration and school weapon carrying 1 year after the intervention phase was completed and (2) moderation of program effects by the sex or race/ethnicity of the adolescent. Ninety percent (n = 1,690) of the eighth and ninth graders who completed baseline questionnaires completed the 1-year follow-up assessment. The sample was 51 % female and 26 % minority (of whom 69 % was black and 31 % was of another minority race/ethnicity). There were no baseline treatment group differences in violence outcomes. Treatment condition was significantly associated with peer violence victimization and school weapon carrying at follow-up; there was 12 % less victimization and 31 % less weapon carrying among those exposed to Safe Dates than those among controls. Treatment condition was significantly associated with perpetration among the minority but not among white adolescents; there was 23 % less violence perpetration among minority adolescents exposed to Safe Dates than that among controls. The observed effect sizes were comparable with those of other universal school-based youth violence prevention programs. Implementing Safe Dates may be an efficient way of preventing multiple types of youth violence.

  2. Managing Professional and Nurse-Patient Relationship Boundaries in Mental Health.

    PubMed

    Valente, Sharon M

    2017-01-01

    Caring nurse-patient relationships in mental health settings are key components in helping patients recover. These professional relationships provide a safe, trustworthy, reliable, and secure foundation for therapeutic interactions; however, nurses face challenges in setting and maintaining relationship boundaries. Although patients ask for special privileges, romantic interactions, and social media befriending, or offer expensive gifts, nurses must recognize that these boundary violations may erode trust and harm patients. These violations may also trigger discipline for nurses. Professional relationship guidelines must be applied with thoughtful consideration, and nurses must monitor their emotions and reactions in these relationships. The current article is a sharing of personal experiences about boundaries augmented by evidence in the literature, and focuses on managing potential boundary violations (i.e., social media, sexuality, over-involvement, and gift giving) in mental health settings. [Journal of Psychosocial Nursing and Mental Health Services, 55(1), 45-51.]. Copyright 2017, SLACK Incorporated.

  3. From boundaries to boundary work: middle managers creating inter-organizational change.

    PubMed

    Oldenhof, Lieke; Stoopendaal, Annemiek; Putters, Kim

    2016-11-21

    Purpose In healthcare, organizational boundaries are often viewed as barriers to change. The purpose of this paper is to show how middle managers create inter-organizational change by doing boundary work: the dual act of redrawing boundaries and coordinating work in new ways. Design/methodology/approach Theoretically, the paper draws on the concept of boundary work from Science and Technology Studies. Empirically, the paper is based on an ethnographic investigation of middle managers that participate in a Dutch reform program across health, social care, and housing. Findings The findings show how middle managers create a sense of urgency for inter-organizational change by emphasizing "fragmented" service provision due to professional, sectoral, financial, and geographical boundaries. Rather than eradicating these boundaries, middle managers change the status quo gradually by redrawing composite boundaries. They use boundary objects and a boundary-transcending vocabulary emphasizing the need for societal gains that go beyond production targets of individual organizations. As a result, work is coordinated in new ways in neighborhood teams and professional expertise is being reconfigured. Research limitations/implications Since boundary workers create incremental change, it is necessary to follow their work for a longer period to assess whether boundary work contributes to paradigm change. Practical implications Organizations should pay attention to conditions for boundary work, such as legitimacy of boundary workers and the availability of boundary spaces that function as communities of practice. Originality/value By shifting the focus from boundaries to boundary work, this paper gives valuable insights into "how" boundaries are redrawn and embodied in objects and language.

  4. A methodology of SiP testing based on boundary scan

    NASA Astrophysics Data System (ADS)

    Qin, He; Quan, Haiyang; Han, Yifei; Zhu, Tianrui; Zheng, Tuo

    2017-10-01

    System in Package (SiP) play an important role in portable, aerospace and military electronic with the microminiaturization, light weight, high density, and high reliability. At present, SiP system test has encountered the problem on system complexity and malfunction location with the system scale exponentially increase. For SiP system, this paper proposed a testing methodology and testing process based on the boundary scan technology. Combining the character of SiP system and referencing the boundary scan theory of PCB circuit and embedded core test, the specific testing methodology and process has been proposed. The hardware requirement of the under test SiP system has been provided, and the hardware platform of the testing has been constructed. The testing methodology has the character of high test efficiency and accurate malfunction location.

  5. Boundary fitting based segmentation of fluorescence microscopy images

    NASA Astrophysics Data System (ADS)

    Lee, Soonam; Salama, Paul; Dunn, Kenneth W.; Delp, Edward J.

    2015-03-01

    Segmentation is a fundamental step in quantifying characteristics, such as volume, shape, and orientation of cells and/or tissue. However, quantification of these characteristics still poses a challenge due to the unique properties of microscopy volumes. This paper proposes a 2D segmentation method that utilizes a combination of adaptive and global thresholding, potentials, z direction refinement, branch pruning, end point matching, and boundary fitting methods to delineate tubular objects in microscopy volumes. Experimental results demonstrate that the proposed method achieves better performance than an active contours based scheme.

  6. Implementation Evaluation of "Steering Teens Safe": Engaging Parents to Deliver a New Parent-Based Teen Driving Intervention to Their Teens

    ERIC Educational Resources Information Center

    Ramirez, Marizen; Yang, Jingzhen; Young, Tracy; Roth, Lisa; Garinger, Anne; Snetselaar, Linda; Peek-Asa, Corinne

    2013-01-01

    Parents play a fundamental role in teaching their children safe driving skills to reduce risk of motor vehicle crashes, the leading cause of death for teens. "Steering Teens Safe" is a new parent-based intervention that equips parents with communication skills to talk about, demonstrate, and practice safe driving behaviors and skills…

  7. Experimental investigation on the influence of boundary layer thickness on the base pressure and near-wake flow features of an axisymmetric blunt-based body

    NASA Astrophysics Data System (ADS)

    Mariotti, Alessandro; Buresti, Guido

    2013-11-01

    The influence of the thickness of the boundary layer developing over the surface of an axisymmetric bluff body upon its base pressure and near-wake flow is analyzed experimentally. The model, whose diameter-to-length ratio is d/ l = 0.175, has a forebody with an elliptical contour and a sharp-edged flat base; it is supported above a plate by means of a faired strut. The pressure distributions over the body lateral and base surfaces were obtained using numerous pressure taps, while the boundary layer profiles and the wake velocity field were measured through hot-wire anemometry. The tests were carried out at , at which the boundary layer over the lateral surface of the body becomes turbulent before reaching the base contour. Strips of emery cloth were wrapped in various positions around the body circumference in order to modify the thickness and the characteristics of the boundary layer. The results show that increasing the boundary layer thickness causes a decrease in the base suctions and a corresponding increase in the length of the mean recirculation region present behind the body. In the spectra of the velocity fluctuations measured within and aside the wake, a dominating peak becomes evident in the region downstream of the final part of the recirculation region. The relevant non-dimensional frequency decreases with increasing boundary layer thickness; however, a Strouhal number based on the wake width and the velocity defect at a suitable reference cross section downstream of the recirculation region is found to remain almost constant for the different cases.

  8. A hypersonic aeroheating calculation method based on inviscid outer edge of boundary layer parameters

    NASA Astrophysics Data System (ADS)

    Meng, ZhuXuan; Fan, Hu; Peng, Ke; Zhang, WeiHua; Yang, HuiXin

    2016-12-01

    This article presents a rapid and accurate aeroheating calculation method for hypersonic vehicles. The main innovation is combining accurate of numerical method with efficient of engineering method, which makes aeroheating simulation more precise and faster. Based on the Prandtl boundary layer theory, the entire flow field is divided into inviscid and viscid flow at the outer edge of the boundary layer. The parameters at the outer edge of the boundary layer are numerically calculated from assuming inviscid flow. The thermodynamic parameters of constant-volume specific heat, constant-pressure specific heat and the specific heat ratio are calculated, the streamlines on the vehicle surface are derived and the heat flux is then obtained. The results of the double cone show that at the 0° and 10° angle of attack, the method of aeroheating calculation based on inviscid outer edge of boundary layer parameters reproduces the experimental data better than the engineering method. Also the proposed simulation results of the flight vehicle reproduce the viscid numerical results well. Hence, this method provides a promising way to overcome the high cost of numerical calculation and improves the precision.

  9. A map overlay error model based on boundary geometry

    USGS Publications Warehouse

    Gaeuman, D.; Symanzik, J.; Schmidt, J.C.

    2005-01-01

    An error model for quantifying the magnitudes and variability of errors generated in the areas of polygons during spatial overlay of vector geographic information system layers is presented. Numerical simulation of polygon boundary displacements was used to propagate coordinate errors to spatial overlays. The model departs from most previous error models in that it incorporates spatial dependence of coordinate errors at the scale of the boundary segment. It can be readily adapted to match the scale of error-boundary interactions responsible for error generation on a given overlay. The area of error generated by overlay depends on the sinuosity of polygon boundaries, as well as the magnitude of the coordinate errors on the input layers. Asymmetry in boundary shape has relatively little effect on error generation. Overlay errors are affected by real differences in boundary positions on the input layers, as well as errors in the boundary positions. Real differences between input layers tend to compensate for much of the error generated by coordinate errors. Thus, the area of change measured on an overlay layer produced by the XOR overlay operation will be more accurate if the area of real change depicted on the overlay is large. The model presented here considers these interactions, making it especially useful for estimating errors studies of landscape change over time. ?? 2005 The Ohio State University.

  10. NASA/MSFC ground-based Doppler lidar nocturnal boundary layer experiment (Noblex)

    NASA Technical Reports Server (NTRS)

    Emmitt, G. D.

    1984-01-01

    During the summer of 1982, NASA/MSFC's ground-based CO2 Doppler Lidar Velocimeter (DLV) was deployed at the Denver Stapleton Airport as part of NASA's participation in the JAWS (Joint Airport Weather Studies) program. Configured to measure the radial wind component within a 10 km radius, the conically scanning lidar was used to examine the evolution of a nocturnal boundary layer under the conditions of cloud free skies and rolling terrain. A valley drainage flow was detected and a two dimension flow visualization constructed. The depth of the gravity current was -700 meters while the depth of the creek valley was -150 meters. This deep drainage flow was detectable for distances of 30 to 40 km from the exit region of the valley. Although the sample period (2000 to 2300 CST) was short and only one nocturnal boundary layer case examined, the usefulness of the DLV was demonstrated as well as the care that must be exercised in interpreting lidar data taken in a stable boundary layer in the vicinity of subtle terrain features.

  11. Symbolic Boundary Work in Schools: Demarcating and Denying Ethnic Boundaries

    ERIC Educational Resources Information Center

    Tabib-Calif, Yosepha; Lomsky-Feder, Edna

    2014-01-01

    This article examines the symbolic boundary work that is carried out at a school whose student population is heterogeneous in terms of ethnicity and class. Based on ethnography, the article demonstrates how the school's staff seeks to neutralize ethnic boundaries and their accompanying discourse, while the pupils try to bring ethnic…

  12. Derivation of safe health-based exposure limits for potential consumer exposure to styrene migrating into food from food containers.

    PubMed

    Gelbke, Heinz-Peter; Banton, Marcy; Faes, Eric; Leibold, Edgar; Pemberton, Mark; Duhayon, Sophie

    2014-02-01

    Residual styrene present in polystyrene food packaging may migrate into food at low levels. To assure safe use, safe exposure levels are derived for consumers potentially exposed via food using No/Low Adverse Effect Levels from animal and human studies and assessment factors proposed by European organisations (EFSA, ECHA, ECETOC). Ototoxicity and developmental toxicity in rats and human ototoxicity and effects on colour discrimination have been identified as the most relevant toxicological properties for styrene health assessments. Safe exposure levels derived from animal studies with assessment factors of EFSA and ECHA were expectedly much lower than those using the ECETOC approach. Comparable safe exposure levels were obtained from human data with all sets of assessment factors while ototoxicity in rats led to major differences. The safe exposure levels finally selected based on criteria of science and health protection converged to the range of 90-120 mg/person/d. Assuming a consumption of 1 kg food/d for an adult, this translates to 90 mg styrene migration into 1 kg food as safe for consumers. This assessment supports a health based Specific Migration Limit of 90 ppm, a value somewhat higher than the current overall migration limit of 60 ppm in the European Union. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. The changing role and legitimate boundaries of epidemiology: community-based prevention programmes.

    PubMed

    Tuomilehto, J; Puska, P

    1987-01-01

    Epidemiology is the basic science of public health. It combines medical and social sciences, both of which are developing with new inventions. Therefore, the role of epidemiology and its boundaries are also changing over time. An important role of epidemiology is to develop and implement community-based control programmes for major diseases in the community. Such programmes are essential for large scale public health policy. It is necessary that epidemiological research can as freely as possible test new methods of disease prevention and health promotion. The first community-based control programme for cardiovascular diseases, the North Karelia Project is reviewed against this background. At present, it is still possible to define the boundaries of epidemiology geographically and culturally, but in the future, however, it will become more difficult. There is no doubt that epidemiology will remain as the basic science of public health but the scope of public health problems are growing much wider. These include the prevention of the final epidemic--the destruction of our planet by nuclear bombs. In the control of the existing epidemics and in the prevention of new ones the boundaries of epidemiology cannot stay rigid but they must be changing as new facts about the emerging public health problems are identified.

  14. School-Based Practices and Programs That Promote Safe and Drug-Free Schools. CASE/CCBD Mini-Library Series on Safe, Drug-Free, and Effective Schools.

    ERIC Educational Resources Information Center

    Guthrie, Patricia M.

    This monograph focuses on school-based practices and programs that promote safe and drug-free schools. It begins with a description of the key characteristics of schools with effective programs and provides a model for school-wide support. Necessary steps for developing an effective system of universal prevention are listed and include: (1)…

  15. A procedure of landscape services assessment based on mosaics of patches and boundaries.

    PubMed

    Martín de Agar, Pilar; Ortega, Marta; de Pablo, Carlos L

    2016-09-15

    We develop a procedure for assessing the environmental value of landscape mosaics that simultaneously considers the values of land use patches and the values of the boundaries between them. These boundaries indicate the ecological interactions between the patches. A landscape mosaic is defined as a set of patches and the boundaries between them and corresponds to a spatial pattern of ecological interactions. The procedure is performed in two steps: (i) an environmental assessment of land use patches by means of a function that integrates values based on the goods and services the patches provide, and (ii) an environmental valuation of mosaics using a function that integrates the environmental values of their patches and the types and frequencies of the boundaries between them. This procedure allows us to measure how changes in land uses or in their spatial arrangement cause variations in the environmental value of landscape mosaics and therefore in that of the whole landscape. The procedure was tested in the Sierra Norte of Madrid (central Spain). The results show that the environmental values of the landscape depend not only on the land use patches but also on the values associated with the pattern of the boundaries within the mosaics. The results also highlight the importance of the boundaries between land use patches as determinants of the goods and services provided by the landscape. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. An Evaluation of a Phase-Lag Boundary Condition for Francis Hydroturbine Simulations Using a Pressure-Based Solver

    NASA Astrophysics Data System (ADS)

    Wouden, Alex; Cimbala, John; Lewis, Bryan

    2014-11-01

    While the periodic boundary condition is useful for handling rotational symmetry in many axisymmetric geometries, its application fails for analysis of rotor-stator interaction (RSI) in multi-stage turbomachinery flow. The inadequacy arises from the underlying geometry where the blade counts per row differ, since the blade counts are crafted to deter the destructive harmonic forces of synchronous blade passing. Therefore, to achieve the computational advantage of modeling a single blade passage per row while preserving the integrity of the RSI, a phase-lag boundary condition is adapted to OpenFOAM® software's incompressible pressure-based solver. The phase-lag construct is accomplished through restating the implicit periodic boundary condition as a constant boundary condition that is updated at each time step with phase-shifted data from the coupled cells adjacent to the boundary. Its effectiveness is demonstrated using a typical Francis hydroturbine modeled as single- and double-passages with phase-lag boundary conditions. The evaluation of the phase-lag condition is based on the correspondence of the overall computational performance and the calculated flow parameters of the phase-lag simulations with those of a baseline full-wheel simulation. Funded in part by DOE Award Number: DE-EE0002667.

  17. Safe and Sound: An Educational Leader's Guide to Evidence-Based Social and Emotional Learning (SEL) Programs. Illinois Edition

    ERIC Educational Resources Information Center

    Collaborative for Academic, Social, and Emotional Learning (NJ1), 2005

    2005-01-01

    Based on a three-year study funded by the Office of Safe and Drug-Free Schools (OSDFS) in the U.S. Department of Education, "Safe and Sound" is a comprehensive and inclusive guide for social and emotional learning (SEL) programming. The guide provides a road map for schools and districts that are launching or adding social, emotional,…

  18. An immersed boundary-simplified sphere function-based gas kinetic scheme for simulation of 3D incompressible flows

    NASA Astrophysics Data System (ADS)

    Yang, L. M.; Shu, C.; Yang, W. M.; Wang, Y.; Wu, J.

    2017-08-01

    In this work, an immersed boundary-simplified sphere function-based gas kinetic scheme (SGKS) is presented for the simulation of 3D incompressible flows with curved and moving boundaries. At first, the SGKS [Yang et al., "A three-dimensional explicit sphere function-based gas-kinetic flux solver for simulation of inviscid compressible flows," J. Comput. Phys. 295, 322 (2015) and Yang et al., "Development of discrete gas kinetic scheme for simulation of 3D viscous incompressible and compressible flows," J. Comput. Phys. 319, 129 (2016)], which is often applied for the simulation of compressible flows, is simplified to improve the computational efficiency for the simulation of incompressible flows. In the original SGKS, the integral domain along the spherical surface for computing conservative variables and numerical fluxes is usually not symmetric at the cell interface. This leads the expression of numerical fluxes at the cell interface to be relatively complicated. For incompressible flows, the sphere at the cell interface can be approximately considered to be symmetric as shown in this work. Besides that, the energy equation is usually not needed for the simulation of incompressible isothermal flows. With all these simplifications, the simple and explicit formulations for the conservative variables and numerical fluxes at the cell interface can be obtained. Second, to effectively implement the no-slip boundary condition for fluid flow problems with complex geometry as well as moving boundary, the implicit boundary condition-enforced immersed boundary method [Wu and Shu, "Implicit velocity correction-based immersed boundary-lattice Boltzmann method and its applications," J. Comput. Phys. 228, 1963 (2009)] is introduced into the simplified SGKS. That is, the flow field is solved by the simplified SGKS without considering the presence of an immersed body and the no-slip boundary condition is implemented by the immersed boundary method. The accuracy and efficiency of

  19. Emotion work and boundary maintenance in hospital-based midwifery.

    PubMed

    Hunter, Billie

    2005-09-01

    To identify and explore the emotion work of hospital-based midwives. An ethnographic approach using focus groups, observations and interviews. South Wales, UK. Phase one of the study: self-selected convenience sample of 27 student midwives in first and final years of 3-year (direct entry) and 18-month (post-nursing) programmes. Phase two: opportunistic sample of seven qualified hospital-based midwives. Phase three: Purposive sample of 10 hospital-based midwives working within one National Health Service Trust. Sample representative of a range of clinical locations, length of clinical experience and clinical grades. The emotion work of midwives was strongly influenced by the context of practice. For hospital-based midwives, relationships with midwifery colleagues were of key importance, providing the main source of feedback on individual practice. Negotiating these relationships was a major source of emotion work. Although collegial relationships could provide support and affirmation, they were also a frequent source of conflict, particularly between junior and senior midwives. This discord was underpinned by conflicting ideologies of midwifery practice. The theoretical framework of boundary maintenance was used to interpret the findings. Senior and junior midwives frequently held contradictory models of practice, resulting in competing claims for occupational jurisdiction. Midwives made use of a variety of devices in order to establish and maintain intra-occupational boundaries. Senior midwives attempted to maintain their position through unwritten rules and sanctions, supported by their claim to greater clinical expertise and experience. Junior midwives rarely challenged this authority; their responses were often subversive and designed to create an appearance of compliance. These findings contribute to our understanding of inter-collegial conflict in UK midwifery, providing insights into workplace harassment and low staff morale, which are likely to exacerbate

  20. Safely Conducting Airport Surface Trajectory-Based Operations

    NASA Technical Reports Server (NTRS)

    Jones, Denise R.; Prinzel, Lawrence J., III; Bailey, Randall E.; Arthur, Jarvis J., III; Barnes, James R.

    2014-01-01

    A piloted simulation study was conducted at the National Aeronautics and Space Administration (NASA) Langley Research Center (LaRC) to evaluate the ability to safely conduct surface trajectory-based operations (STBO) by assessing the impact of providing traffic intent information, conflict detection and resolution (CD&R) system capability, and the display of STBO guidance to the flight crew on both head-down and head-up displays (HUD). Nominal and off-nominal conflict scenarios were conducted using 12 airline crews operating in a simulated Memphis International Airport terminal environment. The flight crews met their required time-of-arrival at route end within 10 seconds on 98 percent of the trials, well within the acceptable performance bounds of 15 seconds. Traffic intent information was found to be useful in determining the intent of conflict traffic, with graphical presentation preferred. The CD&R system was only minimally effective during STBO because the prevailing visibility was sufficient for visual detection of incurring traffic. Overall, the pilots indicated STBO increased general situation awareness but also negatively impacted workload, reduced the ability to watch for other traffic, and increased head-down time.

  1. Stability of boundary layer flow based on energy gradient theory

    NASA Astrophysics Data System (ADS)

    Dou, Hua-Shu; Xu, Wenqian; Khoo, Boo Cheong

    2018-05-01

    The flow of the laminar boundary layer on a flat plate is studied with the simulation of Navier-Stokes equations. The mechanisms of flow instability at external edge of the boundary layer and near the wall are analyzed using the energy gradient theory. The simulation results show that there is an overshoot on the velocity profile at the external edge of the boundary layer. At this overshoot, the energy gradient function is very large which results in instability according to the energy gradient theory. It is found that the transverse gradient of the total mechanical energy is responsible for the instability at the external edge of the boundary layer, which induces the entrainment of external flow into the boundary layer. Within the boundary layer, there is a maximum of the energy gradient function near the wall, which leads to intensive flow instability near the wall and contributes to the generation of turbulence.

  2. The anterior interhemispheric approach: a safe and effective approach to anterior skull base lesions.

    PubMed

    Mielke, Dorothee; Mayfrank, Lothar; Psychogios, Marios Nikos; Rohde, Veit

    2014-04-01

    Many approaches to the anterior skull base have been reported. Frequently used are the pterional, the unilateral or bilateral frontobasal, the supraorbital and the frontolateral approach. Recently, endoscopic transnasal approaches have become more popular. The benefits of each approach has to be weighted against its complications and limitations. The aim of this study was to investigate if the anterior interhemispheric approach (AIA) could be a safe and effective alternative approach to tumorous and non-tumorous lesions of the anterior skull base. We screened the operative records of all patients with an anterior skull base lesion undergoing transcranial surgery. We have used the AIA in 61 patients. These were exclusively patients with either olfactory groove meningioma (OGM) (n = 43), ethmoidal dural arteriovenous fistula (dAVF) ( n = 6) or frontobasal fractures of the anterior midline with cerebrospinal fluid (CSF) leakage ( n = 12). Patient records were evaluated concerning accessibility of the lesion, realization of surgical aims (complete tumor removal, dAVF obliteration, closure of the dural tear), and approach related complications. The use of the AIA exclusively in OGMs, ethmoidal dAVFs and midline frontobasal fractures indicated that we considered lateralized frontobasal lesions not suitable to be treated successfully. If restricted to these three pathologies, the AIA is highly effective and safe. The surgical aim (complete tumor removal, complete dAVF occlusion, no rhinorrhea) was achieved in all patients. The complication rate was 11.5 % (wound infection (n = 2; 3.2 %), contusion of the genu of the corpus callosum, subdural hygroma, epileptic seizure, anosmia and asymptomatic bleed into the tumor cavity (n = 1 each). Only the contusion of the corpus callosum was directly related to the approach (1.6 %). Olfaction, if present before surgery, was preserved in all patients, except one (1.6 %). The AIA is an effective and a safe approach

  3. Characteristics of nocturnal coastal boundary layer in Ahtopol based on averaged SODAR profiles

    NASA Astrophysics Data System (ADS)

    Barantiev, Damyan; Batchvarova, Ekaterina; Novitzky, Mikhail

    2014-05-01

    The ground-based remote sensing instruments allow studying the wind regime and the turbulent characteristics of the atmosphere with height, achieving new knowledge and solving practical problems, such as air quality assessments, mesoscale models evaluation with high resolution data, characterization of the exchange processes between the surface and the atmosphere, the climate comfort conditions and the risk for extreme events, etc. Very important parameter in such studies is the height of the atmospheric boundary layer. Acoustic remote sensing data of the coastal atmospheric boundary layer were explored based on over 4-years continuous measurements at the meteorological observatory of Ahtopol (Bulgarian Southern Black Sea Coast) under Bulgarian - Russian scientific agreement. Profiles of 12 parameters from a mid-range acoustic sounding instrument type SCINTEC MFAS are derived and averaged up to about 600 m according filtering based on wind direction (land or sea type of night fowls). From the whole investigated period of 1454 days with 10-minute resolution SODAR data 2296 profiles represented night marine air masses and 1975 profiles represented the night flow from land during the months May to September. Graphics of averaged profiles of 12 SODAR output parameters with different availability of data in height are analyzed for both cases. A marine boundary-layer height of about 300 m is identified in the profiles of standard deviation of vertical wind speed (σw), Turbulent Kinetic Energy (TKE) and eddy dissipation rate (EDR). A nocturnal boundary-layer height of about 420 m was identified from the profiles of the same parameters under flows from land condition. In addition, the Buoyancy Production (BP= σw3/z) profiles were calculated from the standard deviation of the vertical wind speed and the height z above ground.

  4. Compliance boundaries for multiple-frequency base station antennas in three directions.

    PubMed

    Thielens, Arno; Vermeeren, Günter; Kurup, Divya; Joseph, Wout; Martens, Luc

    2013-09-01

    In this article, compliance boundaries and allowed output powers are determined for the front, back, and side of multiple-frequency base station antennas, based on the root-mean-squared electric field, the whole-body averaged specific absorption rate (SAR), and the 10 g averaged SAR in both the limbs and the head and trunk. For this purpose, the basic restrictions and reference levels defined by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) for both the general public and occupational exposure are used. The antennas are designed for Global System for Mobile Communications around 900 MHz (GSM900), GSM1800, High Speed Packet Access (HSPA), and Long Term Evolution (LTE), and are operated with output powers at the individual frequencies up to 300 W. The compliance boundaries are estimated using finite-difference time-domain simulations with the Virtual Family Male and have been determined for three directions with respect to the antennas for 800, 900, 1800, and 2600 MHz. The reference levels are not always conservative when the radiating part of the antenna is small compared to the length of the body. Combined compliance distances, which ensure compliance with all reference levels and basic restrictions, have also been determined for each frequency. A method to determine a conservative estimation of compliance boundaries for multiple-frequency (cumulative) exposure is introduced. Using the errors on the estimated allowed powers, an uncertainty analysis is carried out for the compliance distances. Uncertainties on the compliance distances are found to be smaller than 122%. Copyright © 2013 Wiley Periodicals, Inc.

  5. An Automated Safe-to-Mate (ASTM) Tester

    NASA Technical Reports Server (NTRS)

    Nguyen, Phuc; Scott, Michelle; Leung, Alan; Lin, Michael; Johnson, Thomas

    2013-01-01

    Safe-to-mate testing is a common hardware safety practice where impedance measurements are made on unpowered hardware to verify isolation, continuity, or impedance between pins of an interface connector. A computer-based instrumentation solution has been developed to resolve issues. The ASTM is connected to the circuit under test, and can then quickly, safely, and reliably safe-to-mate the entire connector, or even multiple connectors, at the same time.

  6. A Kernel-free Boundary Integral Method for Elliptic Boundary Value Problems ⋆

    PubMed Central

    Ying, Wenjun; Henriquez, Craig S.

    2013-01-01

    This paper presents a class of kernel-free boundary integral (KFBI) methods for general elliptic boundary value problems (BVPs). The boundary integral equations reformulated from the BVPs are solved iteratively with the GMRES method. During the iteration, the boundary and volume integrals involving Green's functions are approximated by structured grid-based numerical solutions, which avoids the need to know the analytical expressions of Green's functions. The KFBI method assumes that the larger regular domain, which embeds the original complex domain, can be easily partitioned into a hierarchy of structured grids so that fast elliptic solvers such as the fast Fourier transform (FFT) based Poisson/Helmholtz solvers or those based on geometric multigrid iterations are applicable. The structured grid-based solutions are obtained with standard finite difference method (FDM) or finite element method (FEM), where the right hand side of the resulting linear system is appropriately modified at irregular grid nodes to recover the formal accuracy of the underlying numerical scheme. Numerical results demonstrating the efficiency and accuracy of the KFBI methods are presented. It is observed that the number of GM-RES iterations used by the method for solving isotropic and moderately anisotropic BVPs is independent of the sizes of the grids that are employed to approximate the boundary and volume integrals. With the standard second-order FEMs and FDMs, the KFBI method shows a second-order convergence rate in accuracy for all of the tested Dirichlet/Neumann BVPs when the anisotropy of the diffusion tensor is not too strong. PMID:23519600

  7. Realistic Testing of the Safe Affordable Fission Engine (SAFE-100) Thermal Simulator Using Fiber Bragg Gratings

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

    Stinson-Bagby, Kelly L.; Fielder, Robert S.; Van Dyke, Melissa K.

    2004-02-04

    The motivation for the reported research was to support NASA space nuclear power initiatives through the development of advanced fiber optic sensors for space-based nuclear power applications. Distributed high temperature measurements were made with 20 FBG temperature sensors installed in the SAFE-100 thermal simulator at the NASA Marshal Space Flight Center. Experiments were performed at temperatures approaching 800 deg. C and 1150 deg. C for characterization studies of the SAFE-100 core. Temperature profiles were successfully generated for the core during temperature increases and decreases. Related tests in the SAFE-100 successfully provided strain measurement data.

  8. 16 CFR Appendix I to Part 1402 - Recommended Outline for Instruction Booklet on “How To Safely Install Your CB Base Station Antenna”

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... on âHow To Safely Install Your CB Base Station Antennaâ I Appendix I to Part 1402 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT SAFETY ACT REGULATIONS CB BASE STATION... Outline for Instruction Booklet on “How To Safely Install Your CB Base Station Antenna” I. Required...

  9. Language Test as Boundary Object: Perspectives from Test Users in the Healthcare Domain

    ERIC Educational Resources Information Center

    Macqueen, Susy; Pill, John; Knoch, Ute

    2016-01-01

    Objects that sit between intersecting social worlds, such as Language for Specific Purposes (LSP) tests, are "boundary objects"--dynamic, historically derived mechanisms which maintain coherence between worlds (Star & Griesemer, 1989). They emerge initially from sociopolitical mandates, such as the need to ensure a safe and efficient…

  10. Output Feedback-Based Boundary Control of Uncertain Coupled Semilinear Parabolic PDE Using Neurodynamic Programming.

    PubMed

    Talaei, Behzad; Jagannathan, Sarangapani; Singler, John

    2018-04-01

    In this paper, neurodynamic programming-based output feedback boundary control of distributed parameter systems governed by uncertain coupled semilinear parabolic partial differential equations (PDEs) under Neumann or Dirichlet boundary control conditions is introduced. First, Hamilton-Jacobi-Bellman (HJB) equation is formulated in the original PDE domain and the optimal control policy is derived using the value functional as the solution of the HJB equation. Subsequently, a novel observer is developed to estimate the system states given the uncertain nonlinearity in PDE dynamics and measured outputs. Consequently, the suboptimal boundary control policy is obtained by forward-in-time estimation of the value functional using a neural network (NN)-based online approximator and estimated state vector obtained from the NN observer. Novel adaptive tuning laws in continuous time are proposed for learning the value functional online to satisfy the HJB equation along system trajectories while ensuring the closed-loop stability. Local uniformly ultimate boundedness of the closed-loop system is verified by using Lyapunov theory. The performance of the proposed controller is verified via simulation on an unstable coupled diffusion reaction process.

  11. LiveWire interactive boundary extraction algorithm based on Haar wavelet transform and control point set direction search

    NASA Astrophysics Data System (ADS)

    Cheng, Jun; Zhang, Jun; Tian, Jinwen

    2015-12-01

    Based on deep analysis of the LiveWire interactive boundary extraction algorithm, a new algorithm focusing on improving the speed of LiveWire algorithm is proposed in this paper. Firstly, the Haar wavelet transform is carried on the input image, and the boundary is extracted on the low resolution image obtained by the wavelet transform of the input image. Secondly, calculating LiveWire shortest path is based on the control point set direction search by utilizing the spatial relationship between the two control points users provide in real time. Thirdly, the search order of the adjacent points of the starting node is set in advance. An ordinary queue instead of a priority queue is taken as the storage pool of the points when optimizing their shortest path value, thus reducing the complexity of the algorithm from O[n2] to O[n]. Finally, A region iterative backward projection method based on neighborhood pixel polling has been used to convert dual-pixel boundary of the reconstructed image to single-pixel boundary after Haar wavelet inverse transform. The algorithm proposed in this paper combines the advantage of the Haar wavelet transform and the advantage of the optimal path searching method based on control point set direction search. The former has fast speed of image decomposition and reconstruction and is more consistent with the texture features of the image and the latter can reduce the time complexity of the original algorithm. So that the algorithm can improve the speed in interactive boundary extraction as well as reflect the boundary information of the image more comprehensively. All methods mentioned above have a big role in improving the execution efficiency and the robustness of the algorithm.

  12. Identifying chemicals that are planetary boundary threats.

    PubMed

    MacLeod, Matthew; Breitholtz, Magnus; Cousins, Ian T; de Wit, Cynthia A; Persson, Linn M; Rudén, Christina; McLachlan, Michael S

    2014-10-07

    Rockström et al. proposed a set of planetary boundaries that delimit a "safe operating space for humanity". Many of the planetary boundaries that have so far been identified are determined by chemical agents. Other chemical pollution-related planetary boundaries likely exist, but are currently unknown. A chemical poses an unknown planetary boundary threat if it simultaneously fulfills three conditions: (1) it has an unknown disruptive effect on a vital Earth system process; (2) the disruptive effect is not discovered until it is a problem at the global scale, and (3) the effect is not readily reversible. In this paper, we outline scenarios in which chemicals could fulfill each of the three conditions, then use the scenarios as the basis to define chemical profiles that fit each scenario. The chemical profiles are defined in terms of the nature of the effect of the chemical and the nature of exposure of the environment to the chemical. Prioritization of chemicals in commerce against some of the profiles appears feasible, but there are considerable uncertainties and scientific challenges that must be addressed. Most challenging is prioritizing chemicals for their potential to have a currently unknown effect on a vital Earth system process. We conclude that the most effective strategy currently available to identify chemicals that are planetary boundary threats is prioritization against profiles defined in terms of environmental exposure combined with monitoring and study of the biogeochemical processes that underlie vital Earth system processes to identify currently unknown disruptive effects.

  13. Simulation-based assessment to identify critical gaps in safe anesthesia resident performance.

    PubMed

    Blum, Richard H; Boulet, John R; Cooper, Jeffrey B; Muret-Wagstaff, Sharon L

    2014-01-01

    Valid methods are needed to identify anesthesia resident performance gaps early in training. However, many assessment tools in medicine have not been properly validated. The authors designed and tested use of a behaviorally anchored scale, as part of a multiscenario simulation-based assessment system, to identify high- and low-performing residents with regard to domains of greatest concern to expert anesthesiology faculty. An expert faculty panel derived five key behavioral domains of interest by using a Delphi process (1) Synthesizes information to formulate a clear anesthetic plan; (2) Implements a plan based on changing conditions; (3) Demonstrates effective interpersonal and communication skills with patients and staff; (4) Identifies ways to improve performance; and (5) Recognizes own limits. Seven simulation scenarios spanning pre-to-postoperative encounters were used to assess performances of 22 first-year residents and 8 fellows from two institutions. Two of 10 trained faculty raters blinded to trainee program and training level scored each performance independently by using a behaviorally anchored rating scale. Residents, fellows, facilitators, and raters completed surveys. Evidence supporting the reliability and validity of the assessment scores was procured, including a high generalizability coefficient (ρ = 0.81) and expected performance differences between first-year resident and fellow participants. A majority of trainees, facilitators, and raters judged the assessment to be useful, realistic, and representative of critical skills required for safe practice. The study provides initial evidence to support the validity of a simulation-based performance assessment system for identifying critical gaps in safe anesthesia resident performance early in training.

  14. Stratification of TAD boundaries reveals preferential insulation of super-enhancers by strong boundaries.

    PubMed

    Gong, Yixiao; Lazaris, Charalampos; Sakellaropoulos, Theodore; Lozano, Aurelie; Kambadur, Prabhanjan; Ntziachristos, Panagiotis; Aifantis, Iannis; Tsirigos, Aristotelis

    2018-02-07

    The metazoan genome is compartmentalized in areas of highly interacting chromatin known as topologically associating domains (TADs). TADs are demarcated by boundaries mostly conserved across cell types and even across species. However, a genome-wide characterization of TAD boundary strength in mammals is still lacking. In this study, we first use fused two-dimensional lasso as a machine learning method to improve Hi-C contact matrix reproducibility, and, subsequently, we categorize TAD boundaries based on their insulation score. We demonstrate that higher TAD boundary insulation scores are associated with elevated CTCF levels and that they may differ across cell types. Intriguingly, we observe that super-enhancers are preferentially insulated by strong boundaries. Furthermore, we demonstrate that strong TAD boundaries and super-enhancer elements are frequently co-duplicated in cancer patients. Taken together, our findings suggest that super-enhancers insulated by strong TAD boundaries may be exploited, as a functional unit, by cancer cells to promote oncogenesis.

  15. Safe delivery and newborn care practices in Sindh, Pakistan: a community-based investigation of mothers and health workers.

    PubMed

    Hassan, Hamid; Jokhio, Abdul Hakeem; Winter, Heather; Macarthur, Christine

    2012-08-01

    to determine the prevalence of specific intrapartum practices in Sindh province, Pakistan. a cross-sectional, questionnaire based study. 6 health clinics in Mirpurkhas, Sindh province, rural Pakistan. 225 mothers and 82 health workers. outcome measures were indicators of safe delivery practices and referral following an obstetric complication. Prevalence of unhygienic and unsafe practices in deliveries attended by Traditional Birth Attendants (TBAs) was common. Deliveries by skilled attendants were significantly safer but with some failures in hygienic practices. 29% of women who had experienced an obstetric complication had not received emergency obstetric care. safe delivery practices and newborn care needs to be improved in rural Pakistan. This may be achieved by training health workers and TBAs in safe delivery practices, using safe delivery kits and with an effective referral system. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Preparation and characterization of safe microparticles based on xylan.

    PubMed

    Cartaxo da Costa Urtiga, Silvana; Aquino Azevedo de Lucena Gabi, Camilla; Rodrigues de Araújo Eleamen, Giovanna; Santos Souza, Bartolomeu; Pessôa, Hilzeth de Luna Freire; Marcelino, Henrique Rodrigues; Afonso de Moura Mendonça, Elisângela; Egito, Eryvaldo Sócrates Tabosa do; Oliveira, Elquio Eleamen

    2017-10-01

    This work describes the preparation and evaluation of safe xylan-based microparticles prepared by cross-linking polymerization using sodium trimetaphosphate. The resulting microparticles were evaluated for morphology, particle size, polymer-cross-link agent interaction, and in vitro toxicity. The microparticles showed narrow monodisperse size distributions with their mean sizes being between 3.5 and 12.5 µm in dried state. FT-IR analyzes confirmed the interaction between sodium trimetaphosphate and xylan during the cross-linking process with formation of phosphate ester bonds. Additionally, the X-ray diffraction patterns and FT-IR analyzes suggested that little or no cross-linking agent remained inside the microparticles. Furthermore, the in-vitro studies using Artemia salina and human erythrocytes revealed that the microparticles are not toxic. Therefore, the overall results suggest that these xylan microparticles can be used as a platform for new drug delivery system.

  17. Evaluation of a community-based safe firearm and ammunition storage intervention.

    PubMed

    Simonetti, Joseph A; Rowhani-Rahbar, Ali; King, Cassie; Bennett, Elizabeth; Rivara, Frederick P

    2018-06-01

    Safe firearm storage practices are associated with a lower risk of unintentional and self-inflicted firearm injuries among household members, though many firearms remain unlocked and/or loaded. Conduct a preliminary evaluation of a community-based firearm safety intervention and assess participants' preferences for firearm locking devices and their comfort with potential firearm safety counsellors. Baseline event and follow-up surveys among adult participants to assess changes in firearm storage practices, including whether all household firearms were stored locked, all were unloaded, all ammunition was locked, and a composite measure assessing whether all firearms were locked and unloaded and all ammunition was stored locked. A total of 206 out of 415 participants completed both surveys and were included. Nearly 9 in 10 respondents preferred the firearm lock box rather than a trigger lock. At follow-up, a significantly greater proportion reported that all household firearms were locked (+13.7%) and unloaded (+8.5%) and a non-significantly greater proportion reported that all ammunition was locked (+6.3%). A significantly greater proportion reported practising all three safe firearm and ammunition storage practices at follow-up (+12.6%). A majority reported they would be comfortable or very comfortable discussing firearm safety with various safety counsellors, though women were less likely to do so than men. This intervention that included distribution of a free, participant-selected locking device improved safe firearm storage practices among participants. Differences in participant preferences for devices and safety counsellors suggest that a 'one size fits all' approach may be inadequate in affecting population-level storage practices. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  18. The importance of the boundary condition in the transport of intensity equation based phase measurement

    NASA Astrophysics Data System (ADS)

    Zhang, Jialin; Chen, Qian; Li, Jiaji; Zuo, Chao

    2017-02-01

    The transport of intensity equation (TIE) is a powerful tool for direct quantitative phase retrieval in microscopy imaging. However, there may be some problems when dealing with the boundary condition of the TIE. The previous work introduces a hard-edged aperture to the camera port of the traditional bright field microscope to generate the boundary signal for the TIE solver. Under this Neumann boundary condition, we can obtain the quantitative phase without any assumption or prior knowledge about the test object and the setup. In this paper, we will demonstrate the effectiveness of this method based on some experiments in practice. The micro lens array will be used for the comparison of two TIE solvers results based on introducing the aperture or not and this accurate quantitative phase imaging technique allows measuring cell dry mass which is used in biology to follow cell cycle, to investigate cell metabolism, or to address effects of drugs.

  19. Observation-based estimation of aerosol-induced reduction of planetary boundary layer height

    NASA Astrophysics Data System (ADS)

    Zou, Jun; Sun, Jianning; Ding, Aijun; Wang, Minghuai; Guo, Weidong; Fu, Congbin

    2017-09-01

    Radiative aerosols are known to influence the surface energy budget and hence the evolution of the planetary boundary layer. In this study, we develop a method to estimate the aerosol-induced reduction in the planetary boundary layer height (PBLH) based on two years of ground-based measurements at a site, the Station for Observing Regional Processes of the Earth System (SORPES), at Nanjing University, China, and radiosonde data from the meteorological station of Nanjing. The observations show that increased aerosol loads lead to a mean decrease of 67.1 W m-2 for downward shortwave radiation (DSR) and a mean increase of 19.2 W m-2 for downward longwave radiation (DLR), as well as a mean decrease of 9.6 Wm-2 for the surface sensible heat flux (SHF) in the daytime. The relative variations of DSR, DLR and SHF are shown as a function of the increment of column mass concentration of particulate matter (PM2.5). High aerosol loading can significantly increase the atmospheric stability in the planetary boundary layer during both daytime and nighttime. Based on the statistical relationship between SHF and PM2.5 column mass concentrations, the SHF under clean atmospheric conditions (same as the background days) is derived. In this case, the derived SHF, together with observed SHF, are then used to estimate changes in the PBLH related to aerosols. Our results suggest that the PBLH decreases more rapidly with increasing aerosol loading at high aerosol loading. When the daytime mean column mass concentration of PM2.5 reaches 200 mg m-2, the decrease in the PBLH at 1600 LST (local standard time) is about 450 m.

  20. A classification of ecological boundaries

    USGS Publications Warehouse

    Strayer, D.L.; Power, M.E.; Fagan, W.F.; Pickett, S.T.A.; Belnap, J.

    2003-01-01

    Ecologists use the term boundary to refer to a wide range of real and conceptual structures. Because imprecise terminology may impede the search for general patterns and theories about ecological boundaries, we present a classification of the attributes of ecological boundaries to aid in communication and theory development. Ecological boundaries may differ in their origin and maintenance, their spatial structure, their function, and their temporal dynamics. A classification system based on these attributes should help ecologists determine whether boundaries are truly comparable. This system can be applied when comparing empirical studies, comparing theories, and testing theoretical predictions against empirical results.

  1. 4Kids.org: Topical, Searchable, and Safe Internet-Based Resource for Children and Youth

    ERIC Educational Resources Information Center

    Bacon, Melanie; Blood, Leslie; Ault, Marilyn; Adams, Doug

    2008-01-01

    4Kids.org is an online resource with an accompanying syndicated print publication created to promote safe access to websites and technology literacy. 4Kids.org, created by ALTEC at the University of Kansas in 1995, provides a variety of Internet-based activities as well as access to a database of websites reviewed for educational content,…

  2. An Estimation of Turbulent Kinetic Energy and Energy Dissipation Rate Based on Atmospheric Boundary Layer Similarity Theory

    NASA Technical Reports Server (NTRS)

    Han, Jongil; Arya, S. Pal; Shaohua, Shen; Lin, Yuh-Lang; Proctor, Fred H. (Technical Monitor)

    2000-01-01

    Algorithms are developed to extract atmospheric boundary layer profiles for turbulence kinetic energy (TKE) and energy dissipation rate (EDR), with data from a meteorological tower as input. The profiles are based on similarity theory and scalings for the atmospheric boundary layer. The calculated profiles of EDR and TKE are required to match the observed values at 5 and 40 m. The algorithms are coded for operational use and yield plausible profiles over the diurnal variation of the atmospheric boundary layer.

  3. Evaluation of Cognitive and Behavioral Effects of Peer Education Model-Based Intervention to Sun Safe in Children

    PubMed Central

    HU, Ping; HAN, Lingli; SHARMA, Manoj; ZENG, Huan; ZHANG, Yong; LI, Hui; ZHAO, Yong

    2014-01-01

    Abstract Background There have been many studies that evidence the health hazards of sunlight exposure, but less study on sun safe intervention model, especially in China. Our aim was to evaluate the cognitive and behavioral effects of a peer education model-based intervention to sun safe in children. Methods Cluster random control intervention was conducted in one district in Chongqing, China. Two primary schools, selected through stratified clustered sampling approach (two grades in each school, three classes in each grade) were designated as intervention (n=304) and control schools (n=305) randomly. 36 students, selected as peer educators in intervention group, were trained for one month. Educational activities such as discussions were organized by peer educator for one month. There was no sun safe education to participants in control school during the project period. The evaluation of changes of sun safe knowledge (the primary outcome), attitude and behavior (the secondary outcome measures) were conducted before intervention and at months of 0, 1 and 6 of the intervention to two groups using quantitative and qualitative methods. Results After the intervention, sun safe knowledge score which gained by the students from intervention group has been remarkably improved, compared to baseline survey (24.48±6.17 vs. 29.51±6.75) (P<0.001), and it kept this high level (29.02±7.96 and. 28.65±8.96), while control group students' scores have made no difference (P=0.410). Most of students have changed their sun safe behavior after the intervention. Conclusion Peer education program is somewhat effective in some dimensions for improving children's understanding of sun safe knowledge and behavior. PMID:25988089

  4. Cool and Safe: Multiplicity in Safe Innovation at Unilever

    ERIC Educational Resources Information Center

    Penders, Bart

    2011-01-01

    This article presents the making of a safe innovation: the application of ice structuring protein (ISP) in edible ices. It argues that safety is not the absence of risk but is an active accomplishment; innovations are not "made safe afterward" but "safe innovations are made". Furthermore, there are multiple safeties to be accomplished in the…

  5. Teaching professional boundaries to psychiatric residents.

    PubMed

    Gabbard, Glen O; Crisp-Han, Holly

    2010-01-01

    The authors demonstrate that the teaching of professional boundaries in psychiatry is an essential component of training to prevent harm to patients and to the profession. The authors illustrate overarching principles that apply to didactic teaching in seminars and to psychotherapy supervision. The teaching of boundaries must be based in sound clinical theory and technique so that transference, countertransference, and frame theory are seen as interwoven with the concept of boundaries and must use case-based learning so that a "one-size-fits-all" approach is avoided. The emphasis in teaching should be on both the clinician's temptations and the management of the patient's wish to transgress therapeutic boundaries.

  6. Sodium Based Heat Pipe Modules for Space Reactor Concepts: Stainless Steel SAFE-100 Core

    NASA Technical Reports Server (NTRS)

    Martin, James J.; Reid, Robert S.

    2004-01-01

    A heat pipe cooled reactor is one of several candidate reactor cores being considered for advanced space power and propulsion systems to support future space exploration applications. Long life heat pipe modules, with designs verified through a combination of theoretical analysis and experimental lifetime evaluations, would be necessary to establish the viability of any of these candidates, including the heat pipe reactor option. A hardware-based program was initiated to establish the infrastructure necessary to build heat pipe modules. This effort, initiated by Los Alamos National Laboratory and referred to as the Safe Affordable Fission Engine (SAFE) project, set out to fabricate and perform non-nuclear testing on a modular heat pipe reactor prototype that can provide 100 kilowatt from the core to an energy conversion system at 700 C. Prototypic heat pipe hardware was designed, fabricated, filled, closed-out and acceptance tested.

  7. Identification and characterization of adolescents' sexual boundaries.

    PubMed

    Wolf, Hilary T; Morrell, Holly E R; Halpern-Felsher, Bonnie L

    2013-07-01

    Adolescents' decisions to have sex may be based on a priori boundaries placed on sex. This study addresses: (1) to what extent adolescents set vaginal sexual boundaries; (2) the types of sexual boundaries most and least likely to be endorsed; and (3) to what extent sexual boundaries vary by sex, race/ethnicity, and sexual experience. A cross-sectional study of 518 students attending 10th grade. Survey measures queried about demographics, ever having sex, and existence of sexual boundaries (e.g., being in love, having an attractive partner) that must be in place before having vaginal sex. The most frequently endorsed boundaries were maturity, commitment, trust, love, and marriage. These boundaries were more frequently endorsed than having a safer-sex method. Compared with females, males were more likely to choose boundaries based on partner attractiveness (p < .001) and avoiding trouble (p < .04). Compared with Asians and Pacific Islanders, whites were more likely to endorse wanting to be a certain age to have sex (p < .01 and p < .05, respectively); Asians and Pacific Islanders were more likely to choose sexual boundaries based on marriage (p's < .05). Adolescents who were sexually experienced were more likely than inexperienced adolescents to endorse boundaries related to relationship characteristics and partner attractiveness (OR = 2.5), and less likely to endorse boundaries related to feeling mature (OR = .34) and waiting until marriage (OR = .34). Identifying adolescents' sexual boundaries should help healthcare professionals better understand under what circumstances adolescents are more or less likely to have sex; and this information should ultimately inform the development of new interventions. Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  8. InaSAFE applications in disaster preparedness

    NASA Astrophysics Data System (ADS)

    Pranantyo, Ignatius Ryan; Fadmastuti, Mahardika; Chandra, Fredy

    2015-04-01

    Disaster preparedness activities aim to reduce the impact of disasters by being better prepared to respond when a disaster occurs. In order to better anticipate requirements during a disaster, contingency planning activities can be undertaken prior to a disaster based on a realistic disaster scenario. InaSAFE is a tool that can inform this process. InaSAFE is a free and open source software that estimates the impact to people and infrastructure from potential hazard scenarios. By using InaSAFE, disaster managers can develop scenarios of disaster impacts (people and infrastructures affected) to inform their contingency plan and emergency response operation plan. While InaSAFE provides the software framework exposure data and hazard data are needed as inputs to run this software. Then InaSAFE can be used to forecast the impact of the hazard scenario to the exposure data. InaSAFE outputs include estimates of the number of people, buildings and roads are affected, list of minimum needs (rice and clean water), and response checklist. InaSAFE is developed by Indonesia's National Disaster Management Agency (BNPB) and the Australian Government, through the Australia-Indonesia Facility for Disaster Reduction (AIFDR), in partnership with the World Bank - Global Facility for Disaster Reduction and Recovery (GFDRR). This software has been used in many parts of Indonesia, including Padang, Maumere, Jakarta, and Slamet Mountain for emergency response and contingency planning.

  9. Boundary streaming with Navier boundary condition.

    PubMed

    Xie, Jin-Han; Vanneste, Jacques

    2014-06-01

    In microfluidic applications involving high-frequency acoustic waves over a solid boundary, the Stokes boundary-layer thickness δ is so small that some non-negligible slip may occur at the fluid-solid interface. This paper assesses the impact of this slip by revisiting the classical problem of steady acoustic streaming over a flat boundary, replacing the no-slip boundary condition with the Navier condition u|_{y=0}=L_{s}∂_{y}u|_{y=0}, where u is the velocity tangent to the boundary y=0, and the parameter L_{s} is the slip length. A general expression is obtained for the streaming velocity across the boundary layer as a function of the dimensionless parameter L_{s}/δ. The limit outside the boundary layer provides an effective slip velocity satisfied by the interior mean flow. Particularizing to traveling and standing waves shows that the boundary slip respectively increases and decreases the streaming velocity.

  10. Ranking of healthcare programmes based on health outcome, health costs and safe delivery of care in hospital pharmacy practice.

    PubMed

    Brisseau, Lionel; Bussières, Jean-François; Bois, Denis; Vallée, Marc; Racine, Marie-Claude; Bonnici, André

    2013-02-01

    To establish a consensual and coherent ranking of healthcare programmes that involve the presence of ward-based and clinic-based clinical pharmacists, based on health outcome, health costs and safe delivery of care. This descriptive study was derived from a structured dialogue (Delphi technique) among directors of pharmacy department. We established a quantitative profile of healthcare programmes at five sites that involved the provision of ward-based and clinic-based pharmaceutical care. A summary table of evidence established a unique quality rating per inpatient (clinic-based) or outpatient (ward-based) healthcare programme. Each director rated the perceived impact of pharmaceutical care per inpatient or outpatient healthcare programme on three fields: health outcome, health costs and safe delivery of care. They agreed by consensus on the final ranking of healthcare programmes. A ranking was assigned for each of the 18 healthcare programmes for outpatient care and the 17 healthcare programmes for inpatient care involving the presence of pharmacists, based on health outcome, health costs and safe delivery of care. There was a good correlation between ranking based on data from a 2007-2008 Canadian report on hospital pharmacy practice and the ranking proposed by directors of pharmacy department. Given the often limited human and financial resources, managers should consider the best evidence available on a profession's impact to plan healthcare services within an organization. Data are few on ranking healthcare programmes in order to prioritize which healthcare programme would mostly benefit from the delivery of pharmaceutical care by ward-based and clinic-based pharmacists. © 2012 The Authors. IJPP © 2012 Royal Pharmaceutical Society.

  11. Backstepping-based boundary control design for a fractional reaction diffusion system with a space-dependent diffusion coefficient.

    PubMed

    Chen, Juan; Cui, Baotong; Chen, YangQuan

    2018-06-11

    This paper presents a boundary feedback control design for a fractional reaction diffusion (FRD) system with a space-dependent (non-constant) diffusion coefficient via the backstepping method. The contribution of this paper is to generalize the results of backstepping-based boundary feedback control for a FRD system with a space-independent (constant) diffusion coefficient to the case of space-dependent diffusivity. For the boundary stabilization problem of this case, a designed integral transformation treats it as a problem of solving a hyperbolic partial differential equation (PDE) of transformation's kernel, then the well posedness of the kernel PDE is solved for the plant with non-constant diffusivity. Furthermore, by the fractional Lyapunov stability (Mittag-Leffler stability) theory and the backstepping-based boundary feedback controller, the Mittag-Leffler stability of the closed-loop FRD system with non-constant diffusivity is proved. Finally, an extensive numerical example for this closed-loop FRD system with non-constant diffusivity is presented to verify the effectiveness of our proposed controller. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  12. Implementation of Safe-by-Design for Nanomaterial Development and Safe Innovation: Why We Need a Comprehensive Approach

    PubMed Central

    Kraegeloh, Annette; Suarez-Merino, Blanca; Sluijters, Teun; Micheletti, Christian

    2018-01-01

    Manufactured nanomaterials (MNMs) are regarded as key components of innovations in various fields with high potential impact (e.g., energy generation and storage, electronics, photonics, diagnostics, theranostics, or drug delivery agents). Widespread use of MNMs raises concerns about their safety for humans and the environment, possibly limiting the impact of the nanotechnology-based innovation. The development of safe MNMs and nanoproducts has to result in a safe as well as functional material or product. Its safe use, and disposal at the end of its life cycle must be taken into account too. However, not all MNMs are similarly useful for all applications, some might bear a higher hazard potential than others, and use scenarios could lead to different exposure probabilities. To improve both safety and efficacy of nanotechnology, we think that a new proactive approach is necessary, based on pre-regulatory safety assessment and dialogue between stakeholders. On the basis of the work carried out in different European Union (EU) initiatives, developing and integrating MNMs Safe-by-Design and Trusted Environments (NANoREG, ProSafe, and NanoReg2), we present our point of view here. This concept, when fully developed, will allow for cost effective industrial innovation, and an exchange of key information between regulators and innovators. Regulators are thus informed about incoming innovations in good time, supporting a proactive regulatory action. The final goal is to contribute to the nanotechnology governance, having faster, cheaper, effective, and safer nano-products on the market. PMID:29661997

  13. Implementation of Safe-by-Design for Nanomaterial Development and Safe Innovation: Why We Need a Comprehensive Approach.

    PubMed

    Kraegeloh, Annette; Suarez-Merino, Blanca; Sluijters, Teun; Micheletti, Christian

    2018-04-14

    Manufactured nanomaterials (MNMs) are regarded as key components of innovations in various fields with high potential impact (e.g., energy generation and storage, electronics, photonics, diagnostics, theranostics, or drug delivery agents). Widespread use of MNMs raises concerns about their safety for humans and the environment, possibly limiting the impact of the nanotechnology-based innovation. The development of safe MNMs and nanoproducts has to result in a safe as well as functional material or product. Its safe use, and disposal at the end of its life cycle must be taken into account too. However, not all MNMs are similarly useful for all applications, some might bear a higher hazard potential than others, and use scenarios could lead to different exposure probabilities. To improve both safety and efficacy of nanotechnology, we think that a new proactive approach is necessary, based on pre-regulatory safety assessment and dialogue between stakeholders. On the basis of the work carried out in different European Union (EU) initiatives, developing and integrating MNMs Safe-by-Design and Trusted Environments (NANoREG, ProSafe, and NanoReg2), we present our point of view here. This concept, when fully developed, will allow for cost effective industrial innovation, and an exchange of key information between regulators and innovators. Regulators are thus informed about incoming innovations in good time, supporting a proactive regulatory action. The final goal is to contribute to the nanotechnology governance, having faster, cheaper, effective, and safer nano-products on the market.

  14. C.A.M.P.: A Community-Based Approach to Promoting Safe Sex Behavior in Adolescence.

    ERIC Educational Resources Information Center

    Guzman, Bianca L.; Casad, Bettina J.; Schlehofer-Sutton, Michele M.; Villanueva, Christina M.; Feria, Aida

    The primary goal of this study was to assess the Community Awareness Motivation Partnership (C.A.M.P.) theater intervention based on the behavioral ecological model. C.A.M.P addresses the role of contraceptive use in safe sex behavior through an informative and entertaining culturally relevant dramatization program. Adolescents (N=1613) between…

  15. Arsenic-Safe Aquifers in Coastal Bangladesh: AN Investigation with Ordinary Kriging Estimation

    NASA Astrophysics Data System (ADS)

    Hassan, M. M.; Ahamed, R.

    2017-10-01

    Spatial point pattern is one of the most suitable methods for analysing groundwater arsenic concentrations. Groundwater arsenic poisoning in Bangladesh has been one of the biggest environmental health disasters in recent times. About 85 million people are exposed to arsenic more than 50 μg/L in drinking water. The paper seeks to identify the existing suitable aquifers for arsenic-safe drinking water along with "spatial arsenic discontinuity" using GIS-based spatial geostatistical analysis in a small study site (12.69 km2) in the coastal belt of southwest Bangladesh (Dhopakhali union of Bagerhat district). The relevant spatial data were collected with Geographical Positioning Systems (GPS), arsenic data with field testing kits, tubewell attributes with observation and questionnaire survey. Geostatistics with kriging methods can design water quality monitoring in different aquifers with hydrochemical evaluation by spatial mapping. The paper presents the interpolation of the regional estimates of arsenic data for spatial discontinuity mapping with Ordinary Kriging (OK) method that overcomes the areal bias problem for administrative boundary. This paper also demonstrates the suitability of isopleth maps that is easier to read than choropleth maps. The OK method investigated that around 80 percent of the study site are contaminated following the Bangladesh Drinking Water Standards (BDWS) of 50 μg/L. The study identified a very few scattered "pockets" of arsenic-safe zone at the shallow aquifer.

  16. Intermediate temperature grain boundary embrittlement in nickel-base weld metals

    NASA Astrophysics Data System (ADS)

    Nissley, Nathan Eugene

    The ductility-dip cracking (DDC) susceptibility of NiCrFe filler metals was evaluated using the strain-to-fracture (STF) GleebleRTM-based testing technique1. These high chromium Ni-base filler metals are frequently used in nuclear power plant applications for welding Ni-base Alloy 690 and included INCONELRTM Filler Metal 52 and 52M (FM-52 and FM-52M)2, and a number of FM-52M-type experimental alloys including two with additions of molybdenum and niobium. A wide range in DDC susceptibilities was observed in the tested alloys including significant variations in susceptibility with only small compositional changes. The interpretation of the STF results now includes both the threshold strain for cracking and the transition to "massive" cracking. While the threshold strain is still insightful and an indication of cracking susceptibility, materials which transition rapidly from the threshold strain to "massive" cracking are typically more susceptible to DDC. The spot pre-welds made on the STF samples, used to produce a repeatable microstructure were found to significantly affect the DDC resistance when the current downslope time was altered. Decreasing the downslope time resulted in a faster cooling rate, finer solidification substructure, fewer metastable intragranular precipitates, and a reduced DDC susceptibility. The downslope time has been found to be the most important STF testing variable evaluated to date. A significant decrease in DDC susceptibility was observed in the alloys with Mo and Nb additions. The threshold strain for cracking in the 2.5% Nb and 4% Mo NiCrFe alloy was approximately 10%, and demonstrated a DDC resistance of more than twice that observed in typical FM-82 alloys. This remarkable increase in DDC resistance was attributed to the skeletal precipitate morphology whose large surface area and dense distribution were highly effective at pinning grain boundaries and preventing crack initiation. The resulting wavy or tortuous grain boundaries act to

  17. Amorphous Silica Based Nanomedicine with Safe Carrier Excretion and Enhanced Drug Efficacy

    NASA Astrophysics Data System (ADS)

    Zhang, Silu

    With recent development of nanoscience and nanotechnology, a great amount of efforts have been devoted to nanomedicine development. Among various nanomaterials, silica nanoparticle (NP) is generally accepted as non-toxic, and can provide a versatile platform for drug loading. In addition, the surface of the silica NP is hydrophilic, being favorable for cellular uptake. Therefore, it is considered as one of the most promising candidates to serve as carriers for drugs. The present thesis mainly focuses on the design of silica based nanocarrier-drug systems, aiming at achieving safe nanocarrier excretion from the biological system and enhanced drug efficacy, which two are considered as most important issues in nanomedicine development. To address the safe carrier excretion issue, we have developed a special type of selfdecomposable SiO2-drug composite NPs. By creating a radial concentration gradient of drug in the NP, the drug release occurred simultaneously with the silica carrier decomposition. Such unique characteristic was different from the conventional dense SiO2-drug NP, in which drug was uniformly distributed and can hardly escape the carrier. We found that the controllable release of the drug was primarily determined by diffusion, which was caused by the radial drug concentration gradient in the NP. Escape of the drug molecules then triggered the silica carrier decomposition, which started from the center of the NP and eventually led to its complete fragmentation. The small size of the final carrier fragments enabled their easy excretion via renal systems. Apart from the feature of safe carrier excretion, we also found the controlled release of drugs contribute significantly to the drug efficacy enhancement. By loading an anticancer drug doxorubicin (Dox) to the decomposable SiO 2-methylene blue (MB) NPs, we achieved a self-decomposable SiO 2(MB)-Dox nanomedicine. The gradual escape of drug molecules from NPs and their enabled cytosolic release by optical

  18. Research on the Automatic Fusion Strategy of Fixed Value Boundary Based on the Weak Coupling Condition of Grid Partition

    NASA Astrophysics Data System (ADS)

    Wang, X. Y.; Dou, J. M.; Shen, H.; Li, J.; Yang, G. S.; Fan, R. Q.; Shen, Q.

    2018-03-01

    With the continuous strengthening of power grids, the network structure is becoming more and more complicated. An open and regional data modeling is used to complete the calculation of the protection fixed value based on the local region. At the same time, a high precision, quasi real-time boundary fusion technique is needed to seamlessly integrate the various regions so as to constitute an integrated fault computing platform which can conduct transient stability analysis of covering the whole network with high accuracy and multiple modes, deal with the impact results of non-single fault, interlocking fault and build “the first line of defense” of the power grid. The boundary fusion algorithm in this paper is an automatic fusion algorithm based on the boundary accurate coupling of the networking power grid partition, which takes the actual operation mode for qualification, complete the boundary coupling algorithm of various weak coupling partition based on open-loop mode, improving the fusion efficiency, truly reflecting its transient stability level, and effectively solving the problems of too much data, too many difficulties of partition fusion, and no effective fusion due to mutually exclusive conditions. In this paper, the basic principle of fusion process is introduced firstly, and then the method of boundary fusion customization is introduced by scene description. Finally, an example is given to illustrate the specific algorithm on how it effectively implements the boundary fusion after grid partition and to verify the accuracy and efficiency of the algorithm.

  19. A Gaussian Mixture Model-based continuous Boundary Detection for 3D sensor networks.

    PubMed

    Chen, Jiehui; Salim, Mariam B; Matsumoto, Mitsuji

    2010-01-01

    This paper proposes a high precision Gaussian Mixture Model-based novel Boundary Detection 3D (BD3D) scheme with reasonable implementation cost for 3D cases by selecting a minimum number of Boundary sensor Nodes (BNs) in continuous moving objects. It shows apparent advantages in that two classes of boundary and non-boundary sensor nodes can be efficiently classified using the model selection techniques for finite mixture models; furthermore, the set of sensor readings within each sensor node's spatial neighbors is formulated using a Gaussian Mixture Model; different from DECOMO [1] and COBOM [2], we also formatted a BN Array with an additional own sensor reading to benefit selecting Event BNs (EBNs) and non-EBNs from the observations of BNs. In particular, we propose a Thick Section Model (TSM) to solve the problem of transition between 2D and 3D. It is verified by simulations that the BD3D 2D model outperforms DECOMO and COBOM in terms of average residual energy and the number of BNs selected, while the BD3D 3D model demonstrates sound performance even for sensor networks with low densities especially when the value of the sensor transmission range (r) is larger than the value of Section Thickness (d) in TSM. We have also rigorously proved its correctness for continuous geometric domains and full robustness for sensor networks over 3D terrains.

  20. The topology of non-linear global carbon dynamics: from tipping points to planetary boundaries

    NASA Astrophysics Data System (ADS)

    Anderies, J. M.; Carpenter, S. R.; Steffen, Will; Rockström, Johan

    2013-12-01

    We present a minimal model of land use and carbon cycle dynamics and use it to explore the relationship between non-linear dynamics and planetary boundaries. Only the most basic interactions between land cover and terrestrial, atmospheric, and marine carbon stocks are considered in the model. Our goal is not to predict global carbon dynamics as it occurs in the actual Earth System. Rather, we construct a conceptually reasonable heuristic model of a feedback system between different carbon stocks that captures the qualitative features of the actual Earth System and use it to explore the topology of the boundaries of what can be called a ‘safe operating space’ for humans. The model analysis illustrates the existence of dynamic, non-linear tipping points in carbon cycle dynamics and the potential complexity of planetary boundaries. Finally, we use the model to illustrate some challenges associated with navigating planetary boundaries.

  1. Investigation of safe-life fail-safe criteria for the space shuttle

    NASA Technical Reports Server (NTRS)

    1972-01-01

    An investigation was made to determine the effects of a safe-life design approach and a fail-safe design approach on the space shuttle booster vehicle structure, and to recommend any changes to the structural design criteria. Two configurations of the booster vehicle were considered, one incorporating a delta wing (B-9U configuration) and the other a swept wing (B-16B configuration). Several major structural components of the booster were studied to determine the fatigue life, safe-life, and fail-safe capabilities of the baseline design. Each component was investigated to determine the practicability of applying a safe-life or fail-safe design philosophy, the changes such design approaches might require, and the impact of these changes on weight, cost, development plans, and performance.

  2. Segmentation of neuronal structures using SARSA (λ)-based boundary amendment with reinforced gradient-descent curve shape fitting.

    PubMed

    Zhu, Fei; Liu, Quan; Fu, Yuchen; Shen, Bairong

    2014-01-01

    The segmentation of structures in electron microscopy (EM) images is very important for neurobiological research. The low resolution neuronal EM images contain noise and generally few features are available for segmentation, therefore application of the conventional approaches to identify the neuron structure from EM images is not successful. We therefore present a multi-scale fused structure boundary detection algorithm in this study. In the algorithm, we generate an EM image Gaussian pyramid first, then at each level of the pyramid, we utilize Laplacian of Gaussian function (LoG) to attain structure boundary, we finally assemble the detected boundaries by using fusion algorithm to attain a combined neuron structure image. Since the obtained neuron structures usually have gaps, we put forward a reinforcement learning-based boundary amendment method to connect the gaps in the detected boundaries. We use a SARSA (λ)-based curve traveling and amendment approach derived from reinforcement learning to repair the incomplete curves. Using this algorithm, a moving point starts from one end of the incomplete curve and walks through the image where the decisions are supervised by the approximated curve model, with the aim of minimizing the connection cost until the gap is closed. Our approach provided stable and efficient structure segmentation. The test results using 30 EM images from ISBI 2012 indicated that both of our approaches, i.e., with or without boundary amendment, performed better than six conventional boundary detection approaches. In particular, after amendment, the Rand error and warping error, which are the most important performance measurements during structure segmentation, were reduced to very low values. The comparison with the benchmark method of ISBI 2012 and the recent developed methods also indicates that our method performs better for the accurate identification of substructures in EM images and therefore useful for the identification of imaging

  3. Segmentation of Neuronal Structures Using SARSA (λ)-Based Boundary Amendment with Reinforced Gradient-Descent Curve Shape Fitting

    PubMed Central

    Zhu, Fei; Liu, Quan; Fu, Yuchen; Shen, Bairong

    2014-01-01

    The segmentation of structures in electron microscopy (EM) images is very important for neurobiological research. The low resolution neuronal EM images contain noise and generally few features are available for segmentation, therefore application of the conventional approaches to identify the neuron structure from EM images is not successful. We therefore present a multi-scale fused structure boundary detection algorithm in this study. In the algorithm, we generate an EM image Gaussian pyramid first, then at each level of the pyramid, we utilize Laplacian of Gaussian function (LoG) to attain structure boundary, we finally assemble the detected boundaries by using fusion algorithm to attain a combined neuron structure image. Since the obtained neuron structures usually have gaps, we put forward a reinforcement learning-based boundary amendment method to connect the gaps in the detected boundaries. We use a SARSA (λ)-based curve traveling and amendment approach derived from reinforcement learning to repair the incomplete curves. Using this algorithm, a moving point starts from one end of the incomplete curve and walks through the image where the decisions are supervised by the approximated curve model, with the aim of minimizing the connection cost until the gap is closed. Our approach provided stable and efficient structure segmentation. The test results using 30 EM images from ISBI 2012 indicated that both of our approaches, i.e., with or without boundary amendment, performed better than six conventional boundary detection approaches. In particular, after amendment, the Rand error and warping error, which are the most important performance measurements during structure segmentation, were reduced to very low values. The comparison with the benchmark method of ISBI 2012 and the recent developed methods also indicates that our method performs better for the accurate identification of substructures in EM images and therefore useful for the identification of imaging

  4. Global opportunities in land and water use while staying within the safe (and just) operating space: quantifications of interactions and tradeoffs

    NASA Astrophysics Data System (ADS)

    Gerten, Dieter; Jägermeyr, Jonas; Heck, Vera

    2016-04-01

    Staying within the safe and just operating space as defined by multiple planetary boundaries will be a major challenge especially in view of anticipated future increases in food demand, the potential need for balancing climate change (e.g. through terrestrial carbon dioxide removal) and its impacts, and the water and land demand associated with these goals and measures. This presentation will show simulation results from a comprehensive model-based study on the global potentials of diverse crop management options considered as opportunities to stay within the planetary boundaries for human freshwater use and land-system change. The quantified on-farm options include rainwater harvesting, soil conservation and more efficient irrigation, all of which are designed to use neither more water nor more land for agriculture than is presently the case. Results show that irrigation efficiency improvements could save substantial amounts of water in many river basins (globally 48% of non-productive water consumption in an ambitious scenario), and if rerouted to irrigate neighbouring rainfed systems, could at the same time boost kilocalorie production by 26% globally. Low-tech solutions for small-scale farmers on water-limited croplands show the potential to increase rainfed yields to a similar extent. In combination, such ambitious yet achievable integrated water management strategies could increase global kcal production by 41% and close the water-related yield gap by 62%. Global climate change would have adverse effects on crop yields in many regions, but the improvements in water management quantified here could buffer such effects to a significant degree. Thus, a substantial amount of anticipated future needs for food production could be fulfilled without further approaching / transgressing planetary boundaries. In addition, it will be shown how large-scale biomass plantations for the purpose of terrestrial CO2 removal (climate engineering, potentially implemented should

  5. An Absorbing Boundary Condition for the Lattice Boltzmann Method Based on the Perfectly Matched Layer

    PubMed Central

    Najafi-Yazdi, A.; Mongeau, L.

    2012-01-01

    The Lattice Boltzmann Method (LBM) is a well established computational tool for fluid flow simulations. This method has been recently utilized for low Mach number computational aeroacoustics. Robust and nonreflective boundary conditions, similar to those used in Navier-Stokes solvers, are needed for LBM-based aeroacoustics simulations. The goal of the present study was to develop an absorbing boundary condition based on the perfectly matched layer (PML) concept for LBM. The derivation of formulations for both two and three dimensional problems are presented. The macroscopic behavior of the new formulation is discussed. The new formulation was tested using benchmark acoustic problems. The perfectly matched layer concept appears to be very well suited for LBM, and yielded very low acoustic reflection factor. PMID:23526050

  6. Self-organization of vertebrate mesoderm based on simple boundary conditions.

    PubMed

    Green, Jeremy B A; Dominguez, Isabel; Davidson, Lance A

    2004-11-01

    Embryonic development requires cell movements whose coordination is robust and reproducible. A dramatic example is the primary body axis of vertebrates: despite perturbation, cells in prospective axial tissue coordinate their movements to make an elongated body axis. The spatial cues coordinating these movements are not known. We show here that cells deprived of preexisting spatial cues by physical dissociation and reaggregation nonetheless organize themselves into an axis. Activin-induced cells that are reaggregated into a flat disc initially round up into a ball before elongating perpendicular to the disc. Manipulations of the geometry of the disc and immunofluorescence micrography reveal that the edge of the disc provides a circumferential alignment zone. This finding indicates that physical boundaries provide alignment cues and that circumferential "hoop stress" drives the axial extrusion in a manner resembling late-involuting mesoderm of Xenopus and archenteron elongation in other deuterostome species such as sea urchins. Thus, a population of cells finds its own midline based on the form of the population's boundaries using an edge-aligning mechanism. This process provides a remarkably simple organizing principle that contributes to the reliability of embryonic development as a whole. (c) 2004 Wiley-Liss, Inc.

  7. Exploring the safe and just operating space in an inhomogeneous world

    NASA Astrophysics Data System (ADS)

    Barfuss, Wolfram; Beronov, Boyan; Wiedermann, Marc; Donges, Jonathan

    2015-04-01

    The Anthropocene has become reality during the 20th century, implying that our species is pressuring the Earth's ecosystems on a global scale. In the meantime, the challenge of eradicating poverty has not yet ceased to exist. Effectively dealing with these issues requires us to better understand the driving forces, feedback loops and tipping elements in the whole Earth system, constituted by natural and social components. To take a step forward in this direction, we refine an existing conceptual coevolutionary model of social and ecological domains (COPAN:EXPLOIT) by introducing inhomogeneities in the properties of local renewable resource stocks that are abstracted from real-world data. We then propose an analytical framework, 'the safe and just space'- plot, which aligns with the current debate on how to simultaneously stay within planetary boundaries (Rockström et al., 2009) and at the same time ensure that social foundations are met (Raworth, 2012). This plot presents a practical tool for jointly studying global socio-ecological models as well as real-world observations. First results from comparing the model outputs with real-world data indicate that the current state of the world is neither particularly safe nor particularly just. References: Rockström, Johan, et al. "A safe operating space for humanity." Nature 461.7263 (2009): 472-475. Raworth, Kate. "A safe and just space for humanity: can we live within the doughnut?" Oxfam Discussion Papers (2012): 1-26.

  8. Safe Zones: Creating LGBT Safe Space Ally Programs

    ERIC Educational Resources Information Center

    Poynter, Kerry John; Tubbs, Nancy Jean

    2008-01-01

    This article discusses model LGBT Safe Space Ally programs. These programs, often called "Safe Zones," include self selected students, faculty, and employees who publicly show support by displaying stickers, signs, and other identifiable items. Issues covered in the article include history, development, training, membership, assessment, and…

  9. 44 CFR 65.5 - Revision to special hazard area boundaries with no change to base flood elevation determinations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... the SFHA are “reasonably safe from flooding”, and that they have on file, available upon request by... are “reasonably safe from flooding,” we will process a revision to the SFHA using the criteria set... from flooding.” (6) Data to substantiate the base flood elevation. If we complete a Flood Insurance...

  10. 44 CFR 65.5 - Revision to special hazard area boundaries with no change to base flood elevation determinations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... the SFHA are “reasonably safe from flooding”, and that they have on file, available upon request by... are “reasonably safe from flooding,” we will process a revision to the SFHA using the criteria set... from flooding.” (6) Data to substantiate the base flood elevation. If we complete a Flood Insurance...

  11. Prepare to protect: Operating and maintaining a tornado safe room.

    PubMed

    Herseth, Andrew; Goldsmith-Grinspoon, Jennifer; Scott, Pataya

    2017-06-01

    Operating and maintaining a tornado safe room can be critical to the effective continuity of business operations because a firm's most valuable asset is its people. This paper describes aspects of operations and maintenance (O&M) for existing tornado safe rooms as well as a few planning and design aspects that affect the ultimate operation of a safe room for situations where a safe room is planned, but not yet constructed. The information is based on several Federal Emergency Management Agency safe room publications that provide guidance on emergency management and operations, as well as the design and construction of tornado safe rooms.

  12. The effect of inlet boundary conditions in image-based CFD modeling of aortic flow

    NASA Astrophysics Data System (ADS)

    Madhavan, Sudharsan; Kemmerling, Erica Cherry

    2016-11-01

    CFD of cardiovascular flow is a growing and useful field, but simulations are subject to a number of sources of uncertainty which must be quantified. Our work focuses on the uncertainty introduced by the selection of inlet boundary conditions in an image-based, patient-specific model of the aorta. Specifically, we examined the differences between plug flow, fully developed parabolic flow, linear shear flows, skewed parabolic flow profiles, and Womersley flow. Only the shape of the inlet velocity profile was varied-all other parameters were held constant between simulations, including the physiologically realistic inlet flow rate waveform and outlet flow resistance. We found that flow solutions with different inlet conditions did not exhibit significant differences beyond 1 . 75 inlet diameters from the aortic root. Time averaged wall shear stress (TAWSS) was also calculated. The linear shear velocity boundary condition solution exhibited the highest spatially averaged TAWSS, about 2 . 5 % higher than the fully developed parabolic velocity boundary condition, which had the lowest spatially averaged TAWSS.

  13. Adjusting Wavelet-based Multiresolution Analysis Boundary Conditions for Robust Long-term Streamflow Forecasting Model

    NASA Astrophysics Data System (ADS)

    Maslova, I.; Ticlavilca, A. M.; McKee, M.

    2012-12-01

    There has been an increased interest in wavelet-based streamflow forecasting models in recent years. Often overlooked in this approach are the circularity assumptions of the wavelet transform. We propose a novel technique for minimizing the wavelet decomposition boundary condition effect to produce long-term, up to 12 months ahead, forecasts of streamflow. A simulation study is performed to evaluate the effects of different wavelet boundary rules using synthetic and real streamflow data. A hybrid wavelet-multivariate relevance vector machine model is developed for forecasting the streamflow in real-time for Yellowstone River, Uinta Basin, Utah, USA. The inputs of the model utilize only the past monthly streamflow records. They are decomposed into components formulated in terms of wavelet multiresolution analysis. It is shown that the model model accuracy can be increased by using the wavelet boundary rule introduced in this study. This long-term streamflow modeling and forecasting methodology would enable better decision-making and managing water availability risk.

  14. USING A RISK-BASED METHODOLOGY FOR THE TRANSFER OF RADIOACTIVE MATERIAL WITHIN THE SAVANNAH RIVER SITE BOUNDARY

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

    Loftin, B; Watkins, R; Loibl, M

    2010-06-03

    Shipment of radioactive materials (RAM) is discussed in the Code of Federal Regulations in parts of both 49 CFR and 10 CFR. The regulations provide the requirements and rules necessary for the safe shipment of RAM across public highways, railways, waterways, and through the air. These shipments are sometimes referred to as in-commerce shipments. Shipments of RAM entirely within the boundaries of Department of Energy sites, such as the Savannah River Site (SRS), can be made using methodology allowing provisions to maintain equivalent safety while deviating from the regulations for in-commerce shipments. These onsite shipments are known as transfers atmore » the SRS. These transfers must follow the requirements approved in a site-specific Transportation Safety Document (TSD). The TSD defines how the site will transfer materials so that they have equivalence to the regulations. These equivalences are documented in an Onsite Safety Assessment (OSA). The OSA can show how a particular packaging used onsite is equivalent to that which would be used for an in-commerce shipment. This is known as a deterministic approach. However, when a deterministic approach is not viable, the TSD allows for a risk-based OSA to be written. These risk-based assessments show that if a packaging does not provide the necessary safety to ensure that materials are not released (during normal or accident conditions) then the worst-case release of materials does not result in a dose consequence worse than that defined for the SRS. This paper will discuss recent challenges and successes using this methodology at the SRS.« less

  15. The use of collaboration to implement evidence-based safe practices.

    PubMed

    Clarke, John R

    2013-12-01

    The Pennsylvania Patient Safety Authority receives over 235,000 reports of medical error per year. Near miss and serious event reports of common and interesting problems are analysed to identify best practices for preventing harmful errors. Dissemination of this evidence-based information in the peer-reviewed Pennsylvania Patient Safety Advisory and presentations to medical staffs are not sufficient for adoption of best practices. Adoption of best practices has required working with institutions to identify local barriers to and incentives for adopting best practices and redesigning the delivery system to make desired behaviour easy and undesirable behaviour more difficult. Collaborations, where institutions can learn from the experiences of others, have show decreases in harmful events. The Pennsylvania Program to Prevent Wrong-Site Surgery is used as an example. Two collaborations to prevent wrong-site surgery have been completed, one with 30 institutions in eastern Pennsylvania and one with 19 in western Pennsylvania. The first collaboration achieved a 73% decrease in the rolling average of wrong-site events over 18 months. The second collaboration experienced no wrong-site operating room procedures over more than one year. Significance for public healthSince the Institute of Medicine's To Err is Human identified medical errors as a major cause of death, the public has been interested in the recommendations for reporting of medical errors and implementing safe systems for the delivery of healthcare. The Commonwealth of Pennsylvania has followed those recommendations and found that an essential intermediate step between analysing reports and implementing safe systems is collaborative learning among healthcare institutions. The experience in Pennsylvania should be useful to other public organizations wishing to improve safety.

  16. A Source-Term Based Boundary Layer Bleed/Effusion Model for Passive Shock Control

    NASA Technical Reports Server (NTRS)

    Baurle, Robert A.; Norris, Andrew T.

    2011-01-01

    A modeling framework for boundary layer effusion has been developed based on the use of source (or sink) terms instead of the usual practice of specifying bleed directly as a boundary condition. This framework allows the surface boundary condition (i.e. isothermal wall, adiabatic wall, slip wall, etc.) to remain unaltered in the presence of bleed. This approach also lends itself to easily permit the addition of empirical models for second order effects that are not easily accounted for by simply defining effective transpiration values. Two effusion models formulated for supersonic flows have been implemented into this framework; the Doerffer/Bohning law and the Slater formulation. These models were applied to unit problems that contain key aspects of the flow physics applicable to bleed systems designed for hypersonic air-breathing propulsion systems. The ability of each model to predict bulk bleed properties was assessed, as well as the response of the boundary layer as it passes through and downstream of a porous bleed system. The model assessment was performed with and without the presence of shock waves. Three-dimensional CFD simulations that included the geometric details of the porous plate bleed systems were also carried out to supplement the experimental data, and provide additional insights into the bleed flow physics. Overall, both bleed formulations fared well for the tests performed in this study. However, the sample of test problems considered in this effort was not large enough to permit a comprehensive validation of the models.

  17. Influence of a Game-Based Application on Secondary School Students' Safe Internet Use

    ERIC Educational Resources Information Center

    Durak, Gürhan; Cankaya, Serkan; Yünkül, Eyup; Taylan, Ufuk; Erten, Emine; Akpinar, Sükran

    2017-01-01

    The purpose of this study was to investigate the influence of a game called Wild Web Woods (WWW) designed by the European Council for safe Internet use on secondary school students' safe Internet use. In line with this purpose, for the purpose of determining the students' awareness of safe Internet use, a total of 504 students from different…

  18. Artemisinin-based combination therapies are efficacious and safe for treatment of uncomplicated malaria in HIV-infected Ugandan children.

    PubMed

    Kakuru, Abel; Achan, Jane; Muhindo, Mary K; Ikilezi, Gloria; Arinaitwe, Emmanuel; Mwangwa, Florence; Ruel, Theodore; Clark, Tamara D; Charlebois, Edwin; Rosenthal, Philip J; Havlir, Diane; Kamya, Moses R; Tappero, Jordan W; Dorsey, Grant

    2014-08-01

    Artemisinin-based combination therapies (ACTs) are highly efficacious and safe, but data from human immunodeficiency virus (HIV)-infected children concurrently receiving antiretroviral therapy (ART) and ACTs are limited. We evaluated 28-day outcomes following malaria treatment with artemether-lumefantrine (AL) or dihydroartemisinin-piperaquine (DP) in 2 cohorts of HIV-infected Ugandan children taking various ART regimens. In one cohort, children <6 years of age were randomized to lopinavir/ritonavir (LPV/r) or nonnucleoside reverse transcriptase inhibitor-based ART and treated with AL for uncomplicated malaria. In another cohort, children <12 months of age were started on nevirapine-based ART if they were eligible, and randomized to AL or DP for the treatment of their first and all subsequent uncomplicated malaria episodes. There were 773 and 165 treatments for malaria with AL and DP, respectively. Initial response to therapy was excellent, with 99% clearance of parasites and <1% risk of repeat therapy within 3 days. Recurrent parasitemia within 28 days was common following AL treatment. The risk of recurrent parasitemia was significantly lower among children taking LPV/r-based ART compared with children taking nevirapine-based ART following AL treatment (15.3% vs 35.5%, P = .009), and those treated with DP compared with AL (8.6% vs 36.2%, P < .001). Both ACT regimens were safe and well tolerated. Treatment of uncomplicated malaria with AL or DP was efficacious and safe in HIV-infected children taking ART. However, there was a high risk of recurrent parasitemia following AL treatment, which was significantly lower in children taking LPV/r-based ART compared with nevirapine-based ART. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  19. On safe configurations of a natural-artificial space tether system

    NASA Astrophysics Data System (ADS)

    Rodnikov, A. V.

    2018-05-01

    We study the dynamics of a particle moving under gravitation of precessing dynamically symmetric rigid body if the particle motion is restricted by two unilateral (flexible) constraints realized by two weightless unstretchable tethers with ends fixed at body poles, formed as the intersection of the body surface with the axis of its dynamical symmetry. The system under consideration is a simple model of an original natural-artificial space construction consisting of an asteroid and a space station tethered to each other via two cables. We note that the problem is integrable for the system safe configurations, i.e. for motions along the constraints common boundary (both tethers are tensed) if the body gravitational potential is invariant with respect to rotation about the axis of dynamical symmetry. We study these motions depicting phase portraits for possible values of system parameters. We also deduce conditions for the particle coming off the boundary of constraint(s) (if the tether(s) are slackened) and analyze these conditions, eliminating corresponding areas from phase portraits. We also formulate some statements, concerning the particle safety.

  20. Development of safe, green and high performance ionic liquids-based batteries (ILLIBATT project)

    NASA Astrophysics Data System (ADS)

    Balducci, A.; Jeong, S. S.; Kim, G. T.; Passerini, S.; Winter, M.; Schmuck, M.; Appetecchi, G. B.; Marcilla, R.; Mecerreyes, D.; Barsukov, V.; Khomenko, V.; Cantero, I.; De Meatza, I.; Holzapfel, M.; Tran, N.

    This manuscript presents the work carried out within the European project ILLIBATT, which was dedicated to the development of green, safe and high performance ionic liquids-based lithium batteries. Different types of ionic liquids-based electrolytes were developed in the project, based on different ionic liquids and polymers. Using these electrolytes, the performance of several anodic and cathodic materials has been tested and promising results have been obtained. Also, electrodes were formulated using water soluble binders. Using these innovative components, lithium-ion and lithium-metal battery prototypes (0.7-0.8 Ah) have been assembled and cycled between 100% and 0% SOC. The results of these tests showed that such ionic liquids-based prototypes are able to display high capacity, high coulombic efficiency and high cycle life. Moreover, safety tests showed that the introduction of these alternative electrolytes positively contribute to the safety of the batteries.

  1. Conformal window 2.0: The large Nf safe story

    NASA Astrophysics Data System (ADS)

    Antipin, Oleg; Sannino, Francesco

    2018-06-01

    We extend the phase diagram of SU(N) gauge-fermion theories as a function of the number of flavors and colors to the region in which asymptotic freedom is lost. We argue, using large Nf results, for the existence of an ultraviolet interacting fixed point at a sufficiently large number of flavors opening up to a second ultraviolet conformal window in the number of flavors vs colors phase diagram. We first review the state-of-the-art for the large Nf beta function and then estimate the lower boundary of the ultraviolet window. The theories belonging to this new region are examples of safe non-Abelian quantum electrodynamics, termed here safe QCD. Therefore, according to Wilson, they are fundamental. An important critical quantity is the fermion mass anomalous dimension at the ultraviolet fixed point that we determine at leading order in 1 /Nf . We discover that its value is comfortably below the bootstrap bound. We also investigate the Abelian case and find that at the potential ultraviolet fixed point the related fermion mass anomalous dimension has a singular behavior suggesting that a more careful investigation of its ultimate fate is needed.

  2. Safe Use of Hydrogen and Hydrogen Systems

    NASA Technical Reports Server (NTRS)

    Maes, Miguel

    2006-01-01

    This is a viewgraph presentation that is a course for teaching the safe use of hydrogen. The objectives of the course are 1. To familiarize the student with H2 safety properties 2. To enable the identification, evaluations and addressing of H2 system hazards 3. To teach: a. Safe practices for, b. Design, c. Materials selection, d. H2 system operation, e. Physical principles and empirical observations on which these safe practices are based, f. How to respond to emergency situations involving H2, g How to visualize safety concepts through in-class exercises, h. Identify numerous parameters important to H2 safety.

  3. PIES free boundary stellarator equilibria with improved initial conditions

    NASA Astrophysics Data System (ADS)

    Drevlak, M.; Monticello, D.; Reiman, A.

    2005-07-01

    The MFBE procedure developed by Strumberger (1997 Nucl. Fusion 37 19) is used to provide an improved starting point for free boundary equilibrium computations in the case of W7-X (Nührenberg and Zille 1986 Phys. Lett. A 114 129) using the Princeton iterative equilibrium solver (PIES) code (Reiman and Greenside 1986 Comput. Phys. Commun. 43 157). Transferring the consistent field found by the variational moments equilibrium code (VMEC) (Hirshmann and Whitson 1983 Phys. Fluids 26 3553) to an extended coordinate system using the VMORPH code, a safe margin between plasma boundary and PIES domain is established. The new EXTENDER_P code implements a generalization of the virtual casing principle, which allows field extension both for VMEC and PIES equilibria. This facilitates analysis of the 5/5 islands of the W7-X standard case without including them in the original PIES computation.

  4. Multi-contrast MRI registration of carotid arteries based on cross-sectional images and lumen boundaries

    NASA Astrophysics Data System (ADS)

    Wu, Yu-Xia; Zhang, Xi; Xu, Xiao-Pan; Liu, Yang; Zhang, Guo-Peng; Li, Bao-Juan; Chen, Hui-Jun; Lu, Hong-Bing

    2017-02-01

    Ischemic stroke has great correlation with carotid atherosclerosis and is mostly caused by vulnerable plaques. It's particularly important to analysis the components of plaques for the detection of vulnerable plaques. Recently plaque analysis based on multi-contrast magnetic resonance imaging has attracted great attention. Though multi-contrast MR imaging has potentials in enhanced demonstration of carotid wall, its performance is hampered by the misalignment of different imaging sequences. In this study, a coarse-to-fine registration strategy based on cross-sectional images and wall boundaries is proposed to solve the problem. It includes two steps: a rigid step using the iterative closest points to register the centerlines of carotid artery extracted from multi-contrast MR images, and a non-rigid step using the thin plate spline to register the lumen boundaries of carotid artery. In the rigid step, the centerline was extracted by tracking the crosssectional images along the vessel direction calculated by Hessian matrix. In the non-rigid step, a shape context descriptor is introduced to find corresponding points of two similar boundaries. In addition, the deterministic annealing technique is used to find a globally optimized solution. The proposed strategy was evaluated by newly developed three-dimensional, fast and high resolution multi-contrast black blood MR imaging. Quantitative validation indicated that after registration, the overlap of two boundaries from different sequences is 95%, and their mean surface distance is 0.12 mm. In conclusion, the proposed algorithm has improved the accuracy of registration effectively for further component analysis of carotid plaques.

  5. Morphometric Evaluation of Occipital Condyles: Defining Optimal Trajectories and Safe Screw Lengths for Occipital Condyle-Based Occipitocervical Fixation in Indian Population.

    PubMed

    Bosco, Aju; Venugopal, Prakash; Shetty, Ajoy Prasad; Shanmuganathan, Rajasekaran; Kanna, Rishi Mugesh

    2018-04-01

    Computed tomographic (CT) morphometric analysis. To assess the feasibility and safety of occipital condyle (OC)-based occipitocervical fixation (OCF) in Indians and to define anatomical zones and screw lengths for safe screw placement. Limitations of occipital squama-based OCF has led to development of two novel OC-based OCF techniques. Morphometric analysis was performed on the OCs of 70 Indian adults. The feasibility of placing a 3.5-mm-diameter screw into OCs was investigated. Safe trajectories and screw lengths for OC screws and C0-C1 transarticular screws without hypoglossal canal or atlantooccipital joint compromise were estimated. The average screw length and safe sagittal and medial angulations for OC screws were 19.9±2.3 mm, ≤6.4°±2.4° cranially, and 31.1°±3° medially, respectively. An OC screw could not be accommodated by 27% of the population. The safe sagittal angles and screw lengths for C0-C1 transarticular screw insertion (48.9°±5.7° cranial, 26.7±2.9 mm for junctional entry technique; 36.7°±4.6° cranial, 31.6±2.7 mm for caudal C1 arch entry technique, respectively) were significantly different than those in other populations. The risk of vertebral artery injury was high for the caudal C1 arch entry technique. Screw placement was uncertain in 48% of Indians due to the presence of aberrant anatomy. There were significant differences in the metrics of OC-based OCF between Indian and other populations. Because of the smaller occipital squama dimensions in Indians, OC-based OCF techniques may have a higher application rate and could be a viable alternative/salvage option in selected cases. Preoperative CT, including three-dimensional-CT-angiography (to delineate vertebral artery course), is imperative to avoid complications resulting from aberrant bony and vascular anatomy. Our data can serve as a valuable reference guide in placing these screws safely under fluoroscopic guidance.

  6. Morphometric Evaluation of Occipital Condyles: Defining Optimal Trajectories and Safe Screw Lengths for Occipital Condyle-Based Occipitocervical Fixation in Indian Population

    PubMed Central

    Bosco, Aju; Venugopal, Prakash; Shanmuganathan, Rajasekaran; Kanna, Rishi Mugesh

    2018-01-01

    Study Design Computed tomographic (CT) morphometric analysis. Purpose To assess the feasibility and safety of occipital condyle (OC)-based occipitocervical fixation (OCF) in Indians and to define anatomical zones and screw lengths for safe screw placement. Overview of Literature Limitations of occipital squama-based OCF has led to development of two novel OC-based OCF techniques. Methods Morphometric analysis was performed on the OCs of 70 Indian adults. The feasibility of placing a 3.5-mm-diameter screw into OCs was investigated. Safe trajectories and screw lengths for OC screws and C0–C1 transarticular screws without hypoglossal canal or atlantooccipital joint compromise were estimated. Results The average screw length and safe sagittal and medial angulations for OC screws were 19.9±2.3 mm, ≤6.4°±2.4° cranially, and 31.1°±3° medially, respectively. An OC screw could not be accommodated by 27% of the population. The safe sagittal angles and screw lengths for C0–C1 transarticular screw insertion (48.9°±5.7° cranial, 26.7±2.9 mm for junctional entry technique; 36.7°±4.6° cranial, 31.6±2.7 mm for caudal C1 arch entry technique, respectively) were significantly different than those in other populations. The risk of vertebral artery injury was high for the caudal C1 arch entry technique. Screw placement was uncertain in 48% of Indians due to the presence of aberrant anatomy. Conclusions There were significant differences in the metrics of OC-based OCF between Indian and other populations. Because of the smaller occipital squama dimensions in Indians, OC-based OCF techniques may have a higher application rate and could be a viable alternative/salvage option in selected cases. Preoperative CT, including three-dimensional-CT-angiography (to delineate vertebral artery course), is imperative to avoid complications resulting from aberrant bony and vascular anatomy. Our data can serve as a valuable reference guide in placing these screws safely under

  7. Safe Schools, Safe Communities.

    ERIC Educational Resources Information Center

    Lewis, Julie E.; Pickett, Dean; Pulliam, Janet L.; Schwartz, Richard A.; St. Germaine, Anne-Marie; Underwood, Julie; Worona, Jay

    Schools must work together with agencies, groups, and individuals to eliminate the forces leading children to violence. Chapter 1, "School Safety: Working Together to Keep Schools Safe," stresses the importance of community collaboration in violence prevention. Effective prevention requires sharing information about students, consistent…

  8. Study of flow control by localized volume heating in hypersonic boundary layers

    NASA Astrophysics Data System (ADS)

    Keller, M. A.; Kloker, M. J.; Kirilovskiy, S. V.; Polivanov, P. A.; Sidorenko, A. A.; Maslov, A. A.

    2014-12-01

    Boundary-layer flow control is a prerequisite for a safe and efficient operation of future hypersonic transport systems. Here, the influence of an electric discharge—modeled by a heat-source term in the energy equation—on laminar boundary-layer flows over a flat plate with zero pressure gradient at Mach 3, 5, and 7 is investigated numerically. The aim was to appraise the potential of electro-gasdynamic devices for an application as turbulence generators in the super- and hypersonic flow regime. The results with localized heat-source elements in boundary layers are compared to cases with roughness elements serving as classical passive trips. The numerical simulations are performed using the commercial code ANSYS FLUENT (by ITAM) and the high-order finite-difference DNS code NS3D (by IAG), the latter allowing for the detailed analysis of laminar flow instability. For the investigated setups with steady heating, transition to turbulence is not observed, due to the Reynolds-number lowering effect of heating.

  9. Accurate and robust brain image alignment using boundary-based registration.

    PubMed

    Greve, Douglas N; Fischl, Bruce

    2009-10-15

    The fine spatial scales of the structures in the human brain represent an enormous challenge to the successful integration of information from different images for both within- and between-subject analysis. While many algorithms to register image pairs from the same subject exist, visual inspection shows that their accuracy and robustness to be suspect, particularly when there are strong intensity gradients and/or only part of the brain is imaged. This paper introduces a new algorithm called Boundary-Based Registration, or BBR. The novelty of BBR is that it treats the two images very differently. The reference image must be of sufficient resolution and quality to extract surfaces that separate tissue types. The input image is then aligned to the reference by maximizing the intensity gradient across tissue boundaries. Several lower quality images can be aligned through their alignment with the reference. Visual inspection and fMRI results show that BBR is more accurate than correlation ratio or normalized mutual information and is considerably more robust to even strong intensity inhomogeneities. BBR also excels at aligning partial-brain images to whole-brain images, a domain in which existing registration algorithms frequently fail. Even in the limit of registering a single slice, we show the BBR results to be robust and accurate.

  10. Efficient boundary hunting via vector quantization

    NASA Astrophysics Data System (ADS)

    Diamantini, Claudia; Panti, Maurizio

    2001-03-01

    A great amount of information about a classification problem is contained in those instances falling near the decision boundary. This intuition dates back to the earliest studies in pattern recognition, and in the more recent adaptive approaches to the so called boundary hunting, such as the work of Aha et alii on Instance Based Learning and the work of Vapnik et alii on Support Vector Machines. The last work is of particular interest, since theoretical and experimental results ensure the accuracy of boundary reconstruction. However, its optimization approach has heavy computational and memory requirements, which limits its application on huge amounts of data. In the paper we describe an alternative approach to boundary hunting based on adaptive labeled quantization architectures. The adaptation is performed by a stochastic gradient algorithm for the minimization of the error probability. Error probability minimization guarantees the accurate approximation of the optimal decision boundary, while the use of a stochastic gradient algorithm defines an efficient method to reach such approximation. In the paper comparisons to Support Vector Machines are considered.

  11. Collateral transgression of planetary boundaries due to climate engineering by terrestrial carbon dioxide removal

    NASA Astrophysics Data System (ADS)

    Heck, Vera; Donges, Jonathan F.; Lucht, Wolfgang

    2016-10-01

    The planetary boundaries framework provides guidelines for defining thresholds in environmental variables. Their transgression is likely to result in a shift in Earth system functioning away from the relatively stable Holocene state. As the climate system is approaching critical thresholds of atmospheric carbon, several climate engineering methods are discussed, aiming at a reduction of atmospheric carbon concentrations to control the Earth's energy balance. Terrestrial carbon dioxide removal (tCDR) via afforestation or bioenergy production with carbon capture and storage are part of most climate change mitigation scenarios that limit global warming to less than 2 °C. We analyse the co-evolutionary interaction of societal interventions via tCDR and the natural dynamics of the Earth's carbon cycle. Applying a conceptual modelling framework, we analyse how the degree of anticipation of the climate problem and the intensity of tCDR efforts with the aim of staying within a "safe" level of global warming might influence the state of the Earth system with respect to other carbon-related planetary boundaries. Within the scope of our approach, we show that societal management of atmospheric carbon via tCDR can lead to a collateral transgression of the planetary boundary of land system change. Our analysis indicates that the opportunities to remain in a desirable region within carbon-related planetary boundaries only exist for a small range of anticipation levels and depend critically on the underlying emission pathway. While tCDR has the potential to ensure the Earth system's persistence within a carbon-safe operating space under low-emission pathways, it is unlikely to succeed in a business-as-usual scenario.

  12. Functional protein-based nanomaterial produced in microorganisms recognized as safe: A new platform for biotechnology.

    PubMed

    Cano-Garrido, Olivia; Sánchez-Chardi, Alejandro; Parés, Sílvia; Giró, Irene; Tatkiewicz, Witold I; Ferrer-Miralles, Neus; Ratera, Imma; Natalello, Antonino; Cubarsi, Rafael; Veciana, Jaume; Bach, Àlex; Villaverde, Antonio; Arís, Anna; Garcia-Fruitós, Elena

    2016-10-01

    Inclusion bodies (IBs) are protein-based nanoparticles formed in Escherichia coli through stereospecific aggregation processes during the overexpression of recombinant proteins. In the last years, it has been shown that IBs can be used as nanostructured biomaterials to stimulate mammalian cell attachment, proliferation, and differentiation. In addition, these nanoparticles have also been explored as natural delivery systems for protein replacement therapies. Although the production of these protein-based nanomaterials in E. coli is economically viable, important safety concerns related to the presence of endotoxins in the products derived from this microorganism need to be addressed. Lactic acid bacteria (LAB) are a group of food-grade microorganisms that have been classified as safe by biologically regulatory agencies. In this context, we have demonstrated herein, for the first time, the production of fully functional, IB-like protein nanoparticles in LAB. These nanoparticles have been fully characterized using a wide range of techniques, including field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), Fourier transform infrared (FTIR) spectroscopy, zymography, cytometry, confocal microscopy, and wettability and cell coverage measurements. Our results allow us to conclude that these materials share the main physico-chemical characteristics with IBs from E. coli and moreover are devoid of any harmful endotoxin contaminant. These findings reveal a new platform for the production of protein-based safe products with high pharmaceutical interest. The development of both natural and synthetic biomaterials for biomedical applications is a field in constant development. In this context, E. coli is a bacteria that has been widely studied for its ability to naturally produce functional biomaterials with broad biomedical uses. Despite being effective, products derived from this species contain membrane

  13. Effectiveness of community based Safe Motherhood promoters in improving the utilization of obstetric care. The case of Mtwara Rural District in Tanzania.

    PubMed

    Mushi, Declare; Mpembeni, Rose; Jahn, Albrecht

    2010-04-01

    In Tanzania, maternal mortality ratio remains unacceptably high at 578/100,000 live births. Despite a high coverage of antenatal care (96%), only 44% of deliveries take place within the formal health services. Still, "Ensure skilled attendant at birth" is acknowledged as one of the most effective interventions to reduce maternal deaths. Exploring the potential of community-based interventions in increasing the utilization of obstetric care, the study aimed at developing, testing and assessing a community-based safe motherhood intervention in Mtwara rural District of Tanzania. This community-based intervention was designed as a pre-post comparison study, covering 4 villages with a total population of 8300. Intervention activities were implemented by 50 trained safe motherhood promoters (SMPs). Their tasks focused on promoting early and complete antenatal care visits and delivery with a skilled attendant. Data on all 512 deliveries taking place from October 2004 to November 2006 were collected by the SMPs and cross-checked with health service records. In addition 242 respondents were interviewed with respect to knowledge on safe motherhood issues and their perception of the SMP's performance. Skilled delivery attendance was our primary outcome; secondary outcomes included antenatal care attendance and knowledge on Safe Motherhood issues. Deliveries with skilled attendant significantly increased from 34.1% to 51.4% (rho < 0.05). Early ANC booking (4 to 16 weeks) rose significantly from 18.7% at baseline to 37.7% in 2005 and 56.9% (rho < 0.001) at final assessment. After two years 44 (88%) of the SMPs were still active, 79% of pregnant women were visited. Further benefits included the enhancement of male involvement in safe motherhood issues. The study has demonstrated the effectiveness of community-based safe motherhood intervention in promoting the utilization of obstetric care and a skilled attendant at delivery. This improvement is attributed to the SMPs' home

  14. The Violence Continuum: Creating a Safe School Climate

    ERIC Educational Resources Information Center

    Manvell, Elizabeth C.

    2012-01-01

    We expect schools to be a safe haven, but after more than a decade of targeted school violence prevention laws and safety plans, students are still marginalized and bullied to the point of despondence, retaliation, and even suicide. This thoughtful exploration of what makes a school a safe place is based on the understanding that violence is a…

  15. Flame Tests Performed Safely: A Safe and Effective Alternative to the Traditional Flame Test

    ERIC Educational Resources Information Center

    Dogancay, Deborah

    2005-01-01

    The trend toward inquiry-based learning is providing today's students with a more enriching education. When implementing inquiry it is important to recognize the great number of safety concerns that accompany this paradigm shift. Fortunately, with some consideration, teachers can shape students' laboratory experiments into safe and valuable…

  16. The generation of simple compliance boundaries for mobile communication base station antennas using formulae for SAR estimation.

    PubMed

    Thors, B; Hansson, B; Törnevik, C

    2009-07-07

    In this paper, a procedure is proposed for generating simple and practical compliance boundaries for mobile communication base station antennas. The procedure is based on a set of formulae for estimating the specific absorption rate (SAR) in certain directions around a class of common base station antennas. The formulae, given for both whole-body and localized SAR, require as input the frequency, the transmitted power and knowledge of antenna-related parameters such as dimensions, directivity and half-power beamwidths. With knowledge of the SAR in three key directions it is demonstrated how simple and practical compliance boundaries can be generated outside of which the exposure levels do not exceed certain limit values. The conservativeness of the proposed procedure is discussed based on results from numerical radio frequency (RF) exposure simulations with human body phantoms from the recently developed Virtual Family.

  17. Setting priorities for safe motherhood interventions in resource-scarce settings.

    PubMed

    Prata, Ndola; Sreenivas, Amita; Greig, Fiona; Walsh, Julia; Potts, Malcolm

    2010-01-01

    Guide policy-makers in prioritizing safe motherhood interventions. Three models (LOW, MED, HIGH) were constructed based on 34 sub-Saharan African countries to assess the relative cost-effectiveness of available safe motherhood interventions. Cost and effectiveness data were compiled and inserted into the WHO Mother Baby Package Costing Spreadsheet. For each model we assessed the percentage in maternal mortality reduction after implementing all interventions, and optimal combinations of interventions given restricted budgets of US$ 0.50, US$ 1.00, US$ 1.50 per capital maternal health expenditures respectively for LOW, MED, and HIGH models. The most cost-effective interventions were family planning and safe abortion (fpsa), antenatal care including misoprostol distribution for postpartum hemorrhage prevention at home deliveries (anc-miso), followed by sepsis treatment (sepsis) and facility-based postpartum hemorrhage management (pph). The combination of interventions that avert the greatest number of maternal deaths should be prioritized and expanded to cover the greatest number of women at risk. Those which save the most number of lives in each model are 'fpsa, anc-miso' and 'fpsa, sepsis, safe delivery' for LOW; 'fpsa, anc-miso' and 'fpsa, sepsis, safe delivery' for MED; and 'fpsa, anc-miso, sepsis, eclampsia treatment, safe delivery' for HIGH settings. Safe motherhood interventions save a significant number of newborn lives.

  18. Ergonomics: safe patient handling and mobility.

    PubMed

    Hallmark, Beth; Mechan, Patricia; Shores, Lynne

    2015-03-01

    This article reviews and investigates the issues surrounding ergonomics, with a specific focus on safe patient handling and mobility. The health care worker of today faces many challenges, one of which is related to the safety of patients. Safe patient handling and mobility is on the forefront of the movement to improve patient safety. This article reviews the risks associated with patient handling and mobility, and informs the reader of current evidence-based practice relevant to this area of care. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Safe teleoperation based on flexible intraoperative planning for robot-assisted laser microsurgery.

    PubMed

    Mattos, Leonardo S; Caldwell, Darwin G

    2012-01-01

    This paper describes a new intraoperative planning system created to improve precision and safety in teleoperated laser microsurgeries. It addresses major safety issues related to real-time control of a surgical laser during teleoperated procedures, which are related to the reliability and robustness of the telecommunication channels. Here, a safe solution is presented, consisting in a new planning system architecture that maintains the flexibility and benefits of real-time teleoperation and keeps the surgeon in control of all surgical actions. The developed system is based on our virtual scalpel system for robot-assisted laser microsurgery, and allows the intuitive use of stylus to create surgical plans directly over live video of the surgical field. In this case, surgical plans are defined as graphic objects overlaid on the live video, which can be easily modified or replaced as needed, and which are transmitted to the main surgical system controller for subsequent safe execution. In the process of improving safety, this new planning system also resulted in improved laser aiming precision and improved capability for higher quality laser procedures, both due to the new surgical plan execution module, which allows very fast and precise laser aiming control. Experimental results presented herein show that, in addition to the safety improvements, the new planning system resulted in a 48% improvement in laser aiming precision when compared to the previous virtual scalpel system.

  20. Ground-Based Lidar for Atmospheric Boundary Layer Ozone Measurements

    NASA Technical Reports Server (NTRS)

    Kuang, Shi; Newchurch, Michael J.; Burris, John; Liu, Xiong

    2013-01-01

    Ground-based lidars are suitable for long-term ozone monitoring as a complement to satellite and ozonesonde measurements. However, current ground-based lidars are unable to consistently measure ozone below 500 m above ground level (AGL) due to both engineering issues and high retrieval sensitivity to various measurement errors. In this paper, we present our instrument design, retrieval techniques, and preliminary results that focus on the high-temporal profiling of ozone within the atmospheric boundary layer (ABL) achieved by the addition of an inexpensive and compact mini-receiver to the previous system. For the first time, to the best of our knowledge, the lowest, consistently achievable observation height has been extended down to 125 m AGL for a ground-based ozone lidar system. Both the analysis and preliminary measurements demonstrate that this lidar measures ozone with a precision generally better than 10% at a temporal resolution of 10 min and a vertical resolution from 150 m at the bottom of the ABL to 550 m at the top. A measurement example from summertime shows that inhomogeneous ozone aloft was affected by both surface emissions and the evolution of ABL structures.

  1. Ground-based lidar for atmospheric boundary layer ozone measurements.

    PubMed

    Kuang, Shi; Newchurch, Michael J; Burris, John; Liu, Xiong

    2013-05-20

    Ground-based lidars are suitable for long-term ozone monitoring as a complement to satellite and ozonesonde measurements. However, current ground-based lidars are unable to consistently measure ozone below 500 m above ground level (AGL) due to both engineering issues and high retrieval sensitivity to various measurement errors. In this paper, we present our instrument design, retrieval techniques, and preliminary results that focus on the high-temporal profiling of ozone within the atmospheric boundary layer (ABL) achieved by the addition of an inexpensive and compact mini-receiver to the previous system. For the first time, to the best of our knowledge, the lowest, consistently achievable observation height has been extended down to 125 m AGL for a ground-based ozone lidar system. Both the analysis and preliminary measurements demonstrate that this lidar measures ozone with a precision generally better than ±10% at a temporal resolution of 10 min and a vertical resolution from 150 m at the bottom of the ABL to 550 m at the top. A measurement example from summertime shows that inhomogeneous ozone aloft was affected by both surface emissions and the evolution of ABL structures.

  2. Numerical investigation of implementation of air-earth boundary by acoustic-elastic boundary approach

    USGS Publications Warehouse

    Xu, Y.; Xia, J.; Miller, R.D.

    2007-01-01

    The need for incorporating the traction-free condition at the air-earth boundary for finite-difference modeling of seismic wave propagation has been discussed widely. A new implementation has been developed for simulating elastic wave propagation in which the free-surface condition is replaced by an explicit acoustic-elastic boundary. Detailed comparisons of seismograms with different implementations for the air-earth boundary were undertaken using the (2,2) (the finite-difference operators are second order in time and space) and the (2,6) (second order in time and sixth order in space) standard staggered-grid (SSG) schemes. Methods used in these comparisons to define the air-earth boundary included the stress image method (SIM), the heterogeneous approach, the scheme of modifying material properties based on transversely isotropic medium approach, the acoustic-elastic boundary approach, and an analytical approach. The method proposed achieves the same or higher accuracy of modeled body waves relative to the SIM. Rayleigh waves calculated using the explicit acoustic-elastic boundary approach differ slightly from those calculated using the SIM. Numerical results indicate that when using the (2,2) SSG scheme for SIM and our new method, a spatial step of 16 points per minimum wavelength is sufficient to achieve 90% accuracy; 32 points per minimum wavelength achieves 95% accuracy in modeled Rayleigh waves. When using the (2,6) SSG scheme for the two methods, a spatial step of eight points per minimum wavelength achieves 95% accuracy in modeled Rayleigh waves. Our proposed method is physically reasonable and, based on dispersive analysis of simulated seismographs from a layered half-space model, is highly accurate. As a bonus, our proposed method is easy to program and slightly faster than the SIM. ?? 2007 Society of Exploration Geophysicists.

  3. AN EFFICIENT HIGHER-ORDER FAST MULTIPOLE BOUNDARY ELEMENT SOLUTION FOR POISSON-BOLTZMANN BASED MOLECULAR ELECTROSTATICS

    PubMed Central

    Bajaj, Chandrajit; Chen, Shun-Chuan; Rand, Alexander

    2011-01-01

    In order to compute polarization energy of biomolecules, we describe a boundary element approach to solving the linearized Poisson-Boltzmann equation. Our approach combines several important features including the derivative boundary formulation of the problem and a smooth approximation of the molecular surface based on the algebraic spline molecular surface. State of the art software for numerical linear algebra and the kernel independent fast multipole method is used for both simplicity and efficiency of our implementation. We perform a variety of computational experiments, testing our method on a number of actual proteins involved in molecular docking and demonstrating the effectiveness of our solver for computing molecular polarization energy. PMID:21660123

  4. Safe Sleep Practices of Kansas Birthing Hospitals

    PubMed Central

    Ahlers-Schmidt, Carolyn R.; Schunn, Christy; Sage, Cherie; Engel, Matthew; Benton, Mary

    2018-01-01

    Background Sleep-related death is tied with congenital anomalies as the leading cause of infant mortality in Kansas, and external risk factors are present in 83% of these deaths. Hospitals can impact caregiver intentions to follow risk-reduction strategies. This project assessed the current practices and policies of Kansas hospitals with regard to safe sleep. Methods A cross-sectional survey of existing safe sleep practices and policies in Kansas hospitals was performed. Hospitals were categorized based on reported delivery volume and data were compared across hospital sizes. Results Thirty-one of 73 (42%) contacted hospitals responded. Individual survey respondents represented various hospital departments including newborn/well-baby (68%), neonatal intensive care unit (3%) and other non-nursery departments or administration (29%). Fifty-eight percent of respondents reported staff were trained on infant safe sleep; 44% of these held trainings annually. High volume hospitals tended to have more annual training than low or mid volume birth hospitals. Thirty-nine percent reported a safe sleep policy, though most of these (67%) reported never auditing compliance. The top barrier to safe sleep education, regardless of delivery volume, was conflicting patient and family member beliefs. Conclusions Hospital promotion of infant safe sleep is being conducted in Kansas to varying degrees. High and mid volume birth hospitals may need to work more on formal auditing of safe sleep practices, while low volume hospitals may need more staff training. Low volume hospitals also may benefit from access to additional caregiver education materials. Finally, it is important to note hospitals should not be solely responsible for safe sleep education. PMID:29844848

  5. Feeling safe during an inpatient hospitalization: a concept analysis.

    PubMed

    Mollon, Deene

    2014-08-01

    This paper aims to explore the critical attributes of the concept feeling safe. The safe delivery of care is a high priority; however; it is not really known what it means to the patient to 'feel safe' during an inpatient hospitalization. This analysis explores the topic of safety from the patient's perspective. Concept analysis. The data bases of CINAHL, Medline, PsychInfo and Google Scholar for the years 1995-2012 were searched using the terms safe and feeling safe. The eight-step concept analysis method of Walker and Avant was used to analyse the concept of feeling safe. Uses and defining attributes, as well as identified antecedents, consequences and empirical referents, are presented. Case examples are provided to assist in the understanding of defining attributes. Feeling safe is defined as an emotional state where perceptions of care contribute to a sense of security and freedom from harm. Four attributes were identified: trust, cared for, presence and knowledge. Relationship, environment and suffering are the antecedents of feeling safe, while control, hope and relaxed or calm are the consequences. Empirical referents and early development of a theory of feeling safe are explored. This analysis begins the work of synthesizing qualitative research already completed around the concept of feeling safe by defining the key attributes of the concept. Support for the importance of developing patient-centred models of care and creating positive environments where patients receive high-quality care and feel safe is provided. © 2014 John Wiley & Sons Ltd.

  6. Assessing the 'system' in safe systems-based road designs: using cognitive work analysis to evaluate intersection designs.

    PubMed

    Cornelissen, M; Salmon, P M; Stanton, N A; McClure, R

    2015-01-01

    While a safe systems approach has long been acknowledged as the underlying philosophy of contemporary road safety strategies, systemic applications are sparse. This article argues that systems-based methods from the discipline of Ergonomics have a key role to play in road transport design and evaluation. To demonstrate, the Cognitive Work Analysis framework was used to evaluate two road designs - a traditional Melbourne intersection and a cut-through design for future intersections based on road safety safe systems principles. The results demonstrate that, although the cut-through intersection appears different in layout from the traditional intersection, system constraints are not markedly different. Furthermore, the analyses demonstrated that redistribution of constraints in the cut-through intersection resulted in emergent behaviour, which was not anticipated and could prove problematic. Further, based on the lack of understanding of emergent behaviour, similar design induced problems are apparent across both intersections. Specifically, incompatibilities between infrastructure, vehicles and different road users were not dealt with by the proposed design changes. The importance of applying systems methods in the design and evaluation of road transport systems is discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. The SAFE-T assessment tool: derivation and validation of a web-based application for point-of-care evaluation of gastroenterology fellow performance in colonoscopy.

    PubMed

    Kumar, Navin L; Kugener, Guillaume; Perencevich, Molly L; Saltzman, John R

    2018-01-01

    Attending assessment is a critical part of endoscopic education for gastroenterology fellows. The aim of this study was to develop and validate a concise assessment tool to evaluate real-time fellow performance in colonoscopy administered via a web-based application. The Skill Assessment in Fellow Endoscopy Training (SAFE-T) tool was derived as a novel 5-question evaluation tool that captures both summative and formative feedback adapted into a web-based application. A prospective study of 15 gastroenterology fellows (5 fellows each from years 1 to 3 of training) was performed using the SAFE-T tool. An independent reviewer evaluated a subset of these procedures and completed the SAFE-T tool and Mayo Colonoscopy Skills Assessment Tool (MCSAT) for reliability testing. Twenty-six faculty completed 350 SAFE-T evaluations of the 15 fellows in the study. The mean SAFE-T overall score (year 1, 2.00; year 2, 3.84; year 3, 4.28) differentiated each sequential fellow year of training (P < .0001). The mean SAFE-T overall score decreased with increasing case complexity score, with straightforward cases compared with average cases (4.07 vs 3.50, P < .0001), and average cases compared with challenging cases (3.50 vs 3.08, P = .0134). In dual-observed procedures, the SAFE-T tool showed excellent inter-rater reliability with a kappa agreement statistic of 0.898 (P < .0001). Correlation of the SAFE-T overall score with the MCSAT overall hands-on and individual motor scores was excellent (each r > 0.90, P < .0001). We developed and validated the SAFE-T assessment tool, a concise and web-based means of assessing real-time gastroenterology fellow performance in colonoscopy. Copyright © 2018 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  8. Safe sex self-efficacy and safe sex practice in a Southern United States College

    PubMed Central

    Addoh, Ovuokerie; Sng, Eveleen; Loprinzi, Paul D.

    2017-01-01

    Background: The purpose of this study was to assess the association between safe sex self-efficacy and safe-sex practice in a Southern college setting. Methods: Multivariable logistic regression models were used to examine the association between safe sex self-efficacy in four domains (mechanics, partner disapproval, assertiveness, intoxicants) and safe sex practice (outcome variable). Results: For every 1-unit increase in the composite condom use self-efficacy score, there was an 8% increase in the odds of being beyond the median safe-sex practice score (odds ration [OR]: 1.08, 95% CI: 1.02-1.15). Additionally, for every 1-unit increase in intoxicants self-efficacy score, there was a 31% increase in the odds of being beyond the median safe-sex practice score (OR: 1.31, 95% CI: 1.08-1.58). Conclusion: A greater degree of safe-sex self-efficacy is associated with increased odds of safe-sex practice. These findings are informative for the development of targeted approaches to foster safe-sex behavior in Southern US colleges. PMID:28326287

  9. DroidSafe

    DTIC Science & Technology

    2016-12-01

    branches of our work . 3.1 Understanding Sensitive API Call and API Information Usage Android applications are written in a type- safe language (Java...directly invoke resolved targets. Because DroidSafe works with a comprehensive model of the Android environment , it supports precise resolution of...STATEMENT. FOR THE CHIEF ENGINEER: / S / / S / MARK K. WILLIAMS WARREN H. DEBANY, JR. Work Unit Manager

  10. A Safe Ride to School; A Safe Ride Home.

    ERIC Educational Resources Information Center

    Illinois State Board of Education, Springfield.

    Text and illustrations are used to teach safe school bus riding practices. The guide begins with instructions to parents or guardians to set a good example of safe behavior, and to help children learn safety rules and be on time. Instructions to children concern obeying the bus driver, boarding the bus, riding the bus, crossing the road, and using…

  11. Diagnosis of boundary-layer circulations.

    PubMed

    Beare, Robert J; Cullen, Michael J P

    2013-05-28

    Diagnoses of circulations in the vertical plane provide valuable insights into aspects of the dynamics of the climate system. Dynamical theories based on geostrophic balance have proved useful in deriving diagnostic equations for these circulations. For example, semi-geostrophic theory gives rise to the Sawyer-Eliassen equation (SEE) that predicts, among other things, circulations around mid-latitude fronts. A limitation of the SEE is the absence of a realistic boundary layer. However, the coupling provided by the boundary layer between the atmosphere and the surface is fundamental to the climate system. Here, we use a theory based on Ekman momentum balance to derive an SEE that includes a boundary layer (SEEBL). We consider a case study of a baroclinic low-level jet. The SEEBL solution shows significant benefits over Ekman pumping, including accommodating a boundary-layer depth that varies in space and structure, which accounts for buoyancy and momentum advection. The diagnosed low-level jet is stronger than that determined by Ekman balance. This is due to the inclusion of momentum advection. Momentum advection provides an additional mechanism for enhancement of the low-level jet that is distinct from inertial oscillations.

  12. A nonperturbing boundary-layer transition detection

    NASA Astrophysics Data System (ADS)

    Ohare, J. E.

    1985-01-01

    A laser interferometer technique is being applied to the characterization of boundary-layer conditions on models in supersonic and hypersonic wind tunnels in the von Karman Facility at Arnold Engineering Development Center (AEDC). The Boundary-Layer Transition Detector (BLTD), based on lateral interferometry, is applicable for determining the turbulence frequency spectrum of boundary layers in compressible flow. The turbulence, in terms of air density fluctuations, is detected by monitoring interferometric fringe phase shifts (in real time) formed by one beam which passes through the boundary layer and a reference beam which is outside the boundary layer. This technique is nonintrusive to the flow field unlike other commonly used methods such as pitot tube probing and hot-wire anemometry. Model boundary-layer data are presented at Mach 8 and compared with data recorded using other methods during boundary-layer transition from laminar to turbulent flow. Spectra from the BLTD reveal the presence of a high-frequency peak during transition, which is characteristic of spectra obtained with hot wires. The BLTD is described along with operational requirements and limitations.

  13. A Nonperturbing Boundary-Layer Transition Detector

    NASA Astrophysics Data System (ADS)

    O'Hare, J. E.

    1986-01-01

    A laser interferometer technique is being applied to the characterization of boundary-layer conditions on models in supersonic and hypersonic wind tunnels in the von Kaman Facility at Arnold Engineering Development Center (AEDC). The Boundary-Layer Transition Detector (BLTD), based on lateral interferometry, is applicable for determining the turbulence frequency spectrum of boundary layers in compressible flow. The turbulence, in terms of air density fluctuations, is detected by monitoring interferometric fringe phase shifts (in real time) formed by one beam which passes through the boundary layer and a reference beam which is outside the boundary layer. This technique is nonintrusive to the flow field unlike other commonly used methods such as pitot tube probing and hot-wire anemometry. Model boundary-layer data are presented at Mach 8 and compared with data recorded using other methods during boundary-layer transition from laminar to turbulent flow. Spectra from the BLTD reveal the presence of a high-frequency peak during transition, which is characteristic of spectra obtained with hot wires. The BLTD is described along with operational requirements and limitations.

  14. The case for fire safe cigarettes made through industry documents

    PubMed Central

    Gunja, M; Wayne, G; Landman, A; Connolly, G; McGuire, A

    2002-01-01

    Objectives: To examine the extensive research undertaken by the tobacco industry over the past 25 years toward development of a fire safe cigarette. Methods: Research was conducted through a web based search of internal tobacco industry documents made publicly available through the 1998 Master Settlement Agreement. Results: The documents reveal that the tobacco industry produced a fire safe cigarette years ago, but failed to put it on the market. These findings contradict public industry claims that denied the technical feasibility and commercial acceptability of fire safe cigarettes. Internal documents also reveal a decades long, coordinated political strategy used to block proposed legislation and obfuscate the fire safe issue. Conclusions: Federal legislation mandating fire safe cigarettes is needed. PMID:12432160

  15. Detached eddy simulation for turbulent fluid-structure interaction of moving bodies using the constraint-based immersed boundary method

    NASA Astrophysics Data System (ADS)

    Nangia, Nishant; Bhalla, Amneet P. S.; Griffith, Boyce E.; Patankar, Neelesh A.

    2016-11-01

    Flows over bodies of industrial importance often contain both an attached boundary layer region near the structure and a region of massively separated flow near its trailing edge. When simulating these flows with turbulence modeling, the Reynolds-averaged Navier-Stokes (RANS) approach is more efficient in the former, whereas large-eddy simulation (LES) is more accurate in the latter. Detached-eddy simulation (DES), based on the Spalart-Allmaras model, is a hybrid method that switches from RANS mode of solution in attached boundary layers to LES in detached flow regions. Simulations of turbulent flows over moving structures on a body-fitted mesh incur an enormous remeshing cost every time step. The constraint-based immersed boundary (cIB) method eliminates this operation by placing the structure on a Cartesian mesh and enforcing a rigidity constraint as an additional forcing in the Navier-Stokes momentum equation. We outline the formulation and development of a parallel DES-cIB method using adaptive mesh refinement. We show preliminary validation results for flows past stationary bodies with both attached and separated boundary layers along with results for turbulent flows past moving bodies. This work is supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1324585.

  16. Boundary element based multiresolution shape optimisation in electrostatics

    NASA Astrophysics Data System (ADS)

    Bandara, Kosala; Cirak, Fehmi; Of, Günther; Steinbach, Olaf; Zapletal, Jan

    2015-09-01

    We consider the shape optimisation of high-voltage devices subject to electrostatic field equations by combining fast boundary elements with multiresolution subdivision surfaces. The geometry of the domain is described with subdivision surfaces and different resolutions of the same geometry are used for optimisation and analysis. The primal and adjoint problems are discretised with the boundary element method using a sufficiently fine control mesh. For shape optimisation the geometry is updated starting from the coarsest control mesh with increasingly finer control meshes. The multiresolution approach effectively prevents the appearance of non-physical geometry oscillations in the optimised shapes. Moreover, there is no need for mesh regeneration or smoothing during the optimisation due to the absence of a volume mesh. We present several numerical experiments and one industrial application to demonstrate the robustness and versatility of the developed approach.

  17. A nonperturbing boundary-layer transition detector

    NASA Astrophysics Data System (ADS)

    Ohare, J. E.

    1985-11-01

    A laser interferometer technique is being applied to the characterization of boundary-layer conditions on models in supersonic and hypersonic wind tunnels. The boundary-layer transition detector (BLTD), based on lateral interferometry, is applicable for determining the turbulence frequency spectrum of boundary layers in compressible flow. The turbulence, in terms of air density fluctuations, is detected by monitoring interferometric fringe phase shifts (in real time) formed by one beam which passes through the boundary layer and a reference beam which is outside the boundary layer. This technique is nonintrusive to the flow field unlike other commonly used methods such as pitot tube probing and hot-wire anemometry. Data which depict boundary-layer transition from laminar to turbulent flow are presented to provide comparisons of the BLTD with other measurement methods. Spectra from the BLTD reveals the presence of a high-frequency peak during transition which is characteristic of spectra obtained with hot wires. The BLTD is described along with operational requirements and limitations.

  18. Tracking sustainable development with a national barometer for South Africa using a downscaled "safe and just space" framework.

    PubMed

    Cole, Megan J; Bailey, Richard M; New, Mark G

    2014-10-21

    Nations in the 21st century face a complex mix of environmental and social challenges, as highlighted by the on-going Sustainable Development Goals process. The "planetary boundaries" concept [Rockström J, et al. (2009) Nature 461(7263):472-475], and its extension through the addition of social well-being indicators to create a framework for "safe and just" inclusive sustainable development [Raworth K (2012) Nature Climate Change 2(4):225-226], have received considerable attention in science and policy circles. As the chief aim of this framework is to influence public policy, and this happens largely at the national level, we assess whether it can be used at the national scale, using South Africa as a test case. We developed a decision-based methodology for downscaling the framework and created a national "barometer" for South Africa, combining 20 indicators and boundaries for environmental stress and social deprivation. We find that it is possible to maintain the original design and concept of the framework while making it meaningful in the national context, raising new questions and identifying priority areas for action. Our results show that South Africa has exceeded its environmental boundaries for biodiversity loss, marine harvesting, freshwater use, and climate change, and social deprivation is most severe in the areas of safety, income, and employment. Trends since 1994 show improvement in nearly all social indicators, but progression toward or over boundaries for most environmental indicators. The barometer shows that achieving inclusive sustainable development in South Africa requires national and global action on multiple fronts, and careful consideration of the interplay between different environmental domains and development strategies.

  19. Monitoring Syllable Boundaries during Speech Production

    ERIC Educational Resources Information Center

    Jansma, Bernadette M.; Schiller, Niels O.

    2004-01-01

    This study investigated the encoding of syllable boundary information during speech production in Dutch. Based on Levelt's model of phonological encoding, we hypothesized segments and syllable boundaries to be encoded in an incremental way. In a self-monitoring experiment, decisions about the syllable affiliation (first or second syllable) of a…

  20. School Boundary Debate Divides Minnesota Suburb

    ERIC Educational Resources Information Center

    Samuels, Christina A.

    2011-01-01

    The author discusses how an assignment plan intended to keep schools socioeconomically balanced spurs a bitter debate in suburban Eden Prairie. The boundary debate in the 9,700-student Eden Prairie, Minnesota, district has been bruising. Eden Prairie adopted new school attendance boundaries this year based on socioeconomic balance, ensuring for…

  1. Integral Method of Boundary Characteristics: Neumann Condition

    NASA Astrophysics Data System (ADS)

    Kot, V. A.

    2018-05-01

    A new algorithm, based on systems of identical equalities with integral and differential boundary characteristics, is proposed for solving boundary-value problems on the heat conduction in bodies canonical in shape at a Neumann boundary condition. Results of a numerical analysis of the accuracy of solving heat-conduction problems with variable boundary conditions with the use of this algorithm are presented. The solutions obtained with it can be considered as exact because their errors comprise hundredths and ten-thousandths of a persent for a wide range of change in the parameters of a problem.

  2. Evaluation of retrieval methods of daytime convective boundary layer height based on lidar data

    NASA Astrophysics Data System (ADS)

    Li, Hong; Yang, Yi; Hu, Xiao-Ming; Huang, Zhongwei; Wang, Guoyin; Zhang, Beidou; Zhang, Tiejun

    2017-04-01

    The atmospheric boundary layer height is a basic parameter in describing the structure of the lower atmosphere. Because of their high temporal resolution, ground-based lidar data are widely used to determine the daytime convective boundary layer height (CBLH), but the currently available retrieval methods have their advantages and drawbacks. In this paper, four methods of retrieving the CBLH (i.e., the gradient method, the idealized backscatter method, and two forms of the wavelet covariance transform method) from lidar normalized relative backscatter are evaluated, using two artificial cases (an idealized profile and a case similar to real profile), to test their stability and accuracy. The results show that the gradient method is suitable for high signal-to-noise ratio conditions. The idealized backscatter method is less sensitive to the first estimate of the CBLH; however, it is computationally expensive. The results obtained from the two forms of the wavelet covariance transform method are influenced by the selection of the initial input value of the wavelet amplitude. Further sensitivity analysis using real profiles under different orders of magnitude of background counts show that when different initial input values are set, the idealized backscatter method always obtains consistent CBLH. For two wavelet methods, the different CBLH are always obtained with the increase in the wavelet amplitude when noise is significant. Finally, the CBLHs as measured by three lidar-based methods are evaluated by as measured from L-band soundings. The boundary layer heights from two instruments coincide with ±200 m in most situations.

  3. Implementation evaluation of steering teens safe: engaging parents to deliver a new parent-based teen driving intervention to their teens.

    PubMed

    Ramirez, Marizen; Yang, Jingzhen; Young, Tracy; Roth, Lisa; Garinger, Anne; Snetselaar, Linda; Peek-Asa, Corinne

    2013-08-01

    Parents play a fundamental role in teaching their children safe driving skills to reduce risk of motor vehicle crashes, the leading cause of death for teens. Steering Teens Safe is a new parent-based intervention that equips parents with communication skills to talk about, demonstrate, and practice safe driving behaviors and skills with their teens. This implementation evaluation focuses on a sample of 83 parents who delivered Steering Teens Safe to their teens. One-, 2- and 3-month follow-up assessments were conducted with intervention parents to evaluate the self-reported quantity and quality of talking about, demonstrating, and practicing safe driving goals with teens; perceived success and benefit of the program; and barriers to implementation. Over 3 months of follow-up, parents discussed driving goals with their teens for a median of 101.5 minutes. The most frequently addressed topics were general safety principles, including distracted driving, driving in bad weather, wearing a seat belt, and being a safe passenger. Parents spent a median of 30 minutes practicing safe driving skills such as changing lanes. Sixty-seven percent of parents talked to their children about rural road safety, but just 36% demonstrated and half practiced these skills with their teens. Barriers to implementation include time and opportunity barriers and resistant attitudes of their teens. However, barriers neither affected frequency of engagement nor parents' perceived benefit and comfort in delivering the program. Parents with time/opportunity barriers also had higher practice and demonstration times than parents without these barriers. Findings indicate high acceptability among parent implementers and promise for real-world delivery. Future studies are needed to assess intervention impact.

  4. Real-time flutter boundary prediction based on time series models

    NASA Astrophysics Data System (ADS)

    Gu, Wenjing; Zhou, Li

    2018-03-01

    For the purpose of predicting the flutter boundary in real time during flutter flight tests, two time series models accompanied with corresponding stability criterion are adopted in this paper. The first method simplifies a long nonstationary response signal as many contiguous intervals and each is considered to be stationary. The traditional AR model is then established to represent each interval of signal sequence. While the second employs a time-varying AR model to characterize actual measured signals in flutter test with progression variable speed (FTPVS). To predict the flutter boundary, stability parameters are formulated by the identified AR coefficients combined with Jury's stability criterion. The behavior of the parameters is examined using both simulated and wind-tunnel experiment data. The results demonstrate that both methods show significant effectiveness in predicting the flutter boundary at lower speed level. A comparison between the two methods is also given in this paper.

  5. Towards a Viscous Wall Model for Immersed Boundary Methods

    NASA Technical Reports Server (NTRS)

    Brehm, Christoph; Barad, Michael F.; Kiris, Cetin C.

    2016-01-01

    Immersed boundary methods are frequently employed for simulating flows at low Reynolds numbers or for applications where viscous boundary layer effects can be neglected. The primary shortcoming of Cartesian mesh immersed boundary methods is the inability of efficiently resolving thin turbulent boundary layers in high-Reynolds number flow application. The inefficiency of resolving the thin boundary is associated with the use of constant aspect ratio Cartesian grid cells. Conventional CFD approaches can efficiently resolve the large wall normal gradients by utilizing large aspect ratio cells near the wall. This paper presents different approaches for immersed boundary methods to account for the viscous boundary layer interaction with the flow-field away from the walls. Different wall modeling approaches proposed in previous research studies are addressed and compared to a new integral boundary layer based approach. In contrast to common wall-modeling approaches that usually only utilize local flow information, the integral boundary layer based approach keeps the streamwise history of the boundary layer. This allows the method to remain effective at much larger y+ values than local wall modeling approaches. After a theoretical discussion of the different approaches, the method is applied to increasingly more challenging flow fields including fully attached, separated, and shock-induced separated (laminar and turbulent) flows.

  6. Use Medicines Safely

    MedlinePlus

    ... Medicines Safely Print This Topic En español Use Medicines Safely Browse Sections The Basics Overview Prescription Medicines ... Medicines 1 of 7 sections The Basics: Prescription Medicines There are different types of medicine. The 2 ...

  7. Experimental investigation of the micro-ramp based shock wave and turbulent boundary layer interaction control

    NASA Astrophysics Data System (ADS)

    Bo, Wang; Weidong, Liu; Yuxin, Zhao; Xiaoqiang, Fan; Chao, Wang

    2012-05-01

    Using a nanoparticle-based planar laser-scattering technique and supersonic particle image velocimetry, we investigated the effects of micro-ramp control on incident shockwave and boundary-layer interaction (SWBLI) in a low-noise supersonic wind-tunnel with Mach number 2.7 and Reynolds number Rθ = 5845. High spatiotemporal resolution wake structures downstream of the micro-ramps were detected, while a complex evolution process containing a streamwise counter-rotating vortex pair and large-scale hairpin-like vortices with Strouhal number Stδ of about 0.5-0.65 was revealed. The large-scale structures could survive while passing through the SWBLI region. Reflected shockwaves are clearly seen to be distorted accompanied by high-frequency fluctuations. Micro-ramp applications have a distinct influence on flow patterns of the SWBLI field that vary depending on spanwise locations. Both the shock foot and separation line exhibit undulations corresponding with modifications of the velocity distribution of the incoming boundary layer. Moreover, by energizing parts of the boundary flow, the micro-ramp is able to dampen the separation.

  8. 21 CFR 530.22 - Safe levels and analytical methods for food-producing animals.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... analytical method; or (3) Establish a safe level based on other appropriate scientific, technical, or... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Safe levels and analytical methods for food... § 530.22 Safe levels and analytical methods for food-producing animals. (a) FDA may establish a safe...

  9. 21 CFR 530.22 - Safe levels and analytical methods for food-producing animals.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... analytical method; or (3) Establish a safe level based on other appropriate scientific, technical, or... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Safe levels and analytical methods for food... § 530.22 Safe levels and analytical methods for food-producing animals. (a) FDA may establish a safe...

  10. 21 CFR 530.22 - Safe levels and analytical methods for food-producing animals.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... analytical method; or (3) Establish a safe level based on other appropriate scientific, technical, or... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Safe levels and analytical methods for food... § 530.22 Safe levels and analytical methods for food-producing animals. (a) FDA may establish a safe...

  11. 21 CFR 530.22 - Safe levels and analytical methods for food-producing animals.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... analytical method; or (3) Establish a safe level based on other appropriate scientific, technical, or... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Safe levels and analytical methods for food... § 530.22 Safe levels and analytical methods for food-producing animals. (a) FDA may establish a safe...

  12. Monitoring Moving Queries inside a Safe Region

    PubMed Central

    Al-Khalidi, Haidar; Taniar, David; Alamri, Sultan

    2014-01-01

    With mobile moving range queries, there is a need to recalculate the relevant surrounding objects of interest whenever the query moves. Therefore, monitoring the moving query is very costly. The safe region is one method that has been proposed to minimise the communication and computation cost of continuously monitoring a moving range query. Inside the safe region the set of objects of interest to the query do not change; thus there is no need to update the query while it is inside its safe region. However, when the query leaves its safe region the mobile device has to reevaluate the query, necessitating communication with the server. Knowing when and where the mobile device will leave a safe region is widely known as a difficult problem. To solve this problem, we propose a novel method to monitor the position of the query over time using a linear function based on the direction of the query obtained by periodic monitoring of its position. Periodic monitoring ensures that the query is aware of its location all the time. This method reduces the costs associated with communications in client-server architecture. Computational results show that our method is successful in handling moving query patterns. PMID:24696652

  13. Geographic boundary of the “Pacific Anomaly” near the Earth’s core-mantle boundary

    NASA Astrophysics Data System (ADS)

    He, Y.; Wen, L.

    2009-12-01

    Seismic tomography have revealed a broad, seismically low velocity anomaly in the Earth’s lower mantle beneath the Pacific (we term it the “Pacific Anomaly”), surrounded by the circum-Pacific high velocity zone. Here, we determine geographical boundary and average shear velocity structure of the Pacific Anomaly near the core-mantle boundary based on travel time analysis of ScSH-SH and ScS2-SS phases. We further constrain the detailed structure of the transition from the base of the Pacific Anomaly to the northern high velocity zone along two perpendicular cross sections on the basis of forward waveform modeling of the seismic data. Two cross-sections include one great arc across the Anomaly from New Zealand to Alaska and another from Solomon Islands to North America. Our seismic data are collected from those recorded in the China National Digital Seismographic Network, and many permanent and temporal arrays from the Incorporated Research Institutions for Seismology. The observed ScS-SH and ScS2-SS differential travel time residuals allow the entire geographic boundary of the anomaly to be clearly defined. The seismic data suggest that the average shear velocity reduction inside the anomaly reaches -5% in the lowermost 300 km of the mantle. Waveform analysis of the seismic data sampling the edge of the anomaly further validates the model of the boundary previously deduced by differential-travel-time-residual data, and suggests that the northern boundary is characterized by a shear velocity model with the low-velocity region accompanied by a high velocity structure.

  14. On the age of the Jurassic-Cretaceous boundary

    NASA Astrophysics Data System (ADS)

    Lena, Luis; Ramos, Victor; Pimentel, Marcio; Aguirre-Urreta, Beatriz; Naipauer, Maximiliano; Schaltegger, Urs

    2017-04-01

    Calibrating the geologic time is of utmost importance to understanding geological and biological processes throughout Earth history. The Jurassic-Cretaceous boundary has proven to be one of the most problematic boundaries to calibrate in the geologic time. The present definition of the Jurassic-Cretaceous boundary still remains contentious mainly because of the dominant endemic nature of the flora and fauna in stratigraphic sections, which hinders an agreement on a GSSP. Consequently, an absolute and precise age for the boundary is yet to meet an agreement among the community. Additionally, integrating chemical, paleomagnetic or astronomical proxies to aid the definition of the boundary has also proven to be difficult because the boundary lacks any abrupt geochemical changes or recognizable geological events. However, the traditional Berriasella jacobi Subzone is disregarded as a primary marker and the use of calpionellids has been gaining momentum for defining the boundary. The Jurassic Cretaceous boundary in the Vaca Muerta Fm. in the Nuequen Basin of the Andes is a potential candidate for the boundary stratotype because of its high density of ammonites, nannofossils and interbedded datable horizons. Consequently, the Jurassic-Cretaceous boundary is very well defined in the Vaca Muerta Fm. On the basis of both ammonites and nannofossils. Here we present new high-precision U-Pb age determinations from two volcanic ash beds that bracket the age of the Jurassic-Cretaceous boundary: 1) ash bed LLT_14_9, with a 206Pb/238U age of 139.7 Ma, which is 2 meters above Jurassic-Cretaceous boundary based on the Argetiniceras noduliferum (Early Berriasian ) and Substeueroceras Koeneni (Late Tithonian) ammonites zone; and 2) bed LLT_14_10, with an age of 140.1 Ma, located 3m below the J-K boundary based on last occurrence of the nannofossils N. kamptneri minor and N. steinmanni minor. Therefore, we propose that the age of the Jurassic-Cretaceous boundary should be close to 140

  15. Multiscale regime shifts and planetary boundaries.

    PubMed

    Hughes, Terry P; Carpenter, Stephen; Rockström, Johan; Scheffer, Marten; Walker, Brian

    2013-07-01

    Life on Earth has repeatedly displayed abrupt and massive changes in the past, and there is no reason to expect that comparable planetary-scale regime shifts will not continue in the future. Different lines of evidence indicate that regime shifts occur when the climate or biosphere transgresses a tipping point. Whether human activities will trigger such a global event in the near future is uncertain, due to critical knowledge gaps. In particular, we lack understanding of how regime shifts propagate across scales, and whether local or regional tipping points can lead to global transitions. The ongoing disruption of ecosystems and climate, combined with unprecedented breakdown of isolation by human migration and trade, highlights the need to operate within safe planetary boundaries. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Picture Me Safe

    ERIC Educational Resources Information Center

    Irvin, Daniel W.

    1977-01-01

    The validity of well-written articles can be destroyed by poor illustration, especially when the pictures show unsafe practices. The responsibility lies with the author to provide clear printable pictures showing safe working environments and safe practices. (Editor)

  17. Polar CAP Boundary Identification Using Redline Imaging Data

    NASA Astrophysics Data System (ADS)

    Spanswick, E.; Roy, E. A.; Gallardo-Lacourt, B.; Donovan, E.; Ridley, A. J.; Gou, D.

    2017-12-01

    The location of the polar cap boundary is typically detected using low-orbit satellite measurements in which the boundary is identified by its unique signature of a sharp decrease in energy and particle flux poleward of the auroral oval. A previous study based in optical data by Blanchard et al. [1995] suggested that a dramatic gradient in redline aurora may also be an indicator of the polar cap boundary. While this study has been heavily cited, it was only based on few events and its findings have largely gone uncontested. Since the Blanchard study, satellite instrumentation and available auroral data have improved significantly. Auroral imaging has moved well beyond the capabilities of the instrumentation in the previous study in terms of sensitivity and both spatial and temporal resolution. We now have access to decades of optical data from arrays spanning a huge spatial range; none of which was available previously. In this study we have used data from FAST and DMSP satellites in conjunction with the University of Calgary's Narrow-band All-sky Cameras for Auroral Monitoring (NASCAM) ground based auroral imaging array and the REdline Geospace Observatory (REGO) data to assess the viability of automated detection of the polar cap boundary. In our analysis we used redline (630nm) auroral signatures from the ground based imagers around the location of the polar cap boundary observed in satellite data. We have characterized the polar cap boundary luminosity and location using the redline auroral data during different geomagnetic conditions. Our results enable a new tool to automatically identify the polar cap boundary to reach a deeper understanding of the connection between polar cap location and auroral activity.

  18. The MHD simulation of interplanetary space and heliosphere by using the boundary conditions of time-varying magnetic field and IPS-based plasma

    NASA Astrophysics Data System (ADS)

    Hayashi, K.; Tokumaru, M.; Kojima, M.; Fujiki, K.

    2008-12-01

    We present our new boundary treatment to introduce the temporal variation of the observation-based magnetic field and plasma parameters on the inner boundary sphere (at 30 to 50 Rs) to the MHD simulation of the interplanetary space and the simulation results. The boundary treatment to induce the time-variation of the magnetic field including the radial component is essentially same as shown in our previous AGU meetings and newly modified so that the model can also include the variation of the plasma variables detected by IPS (interplanetary scintillation) observation, a ground-based remote sensing technique for the solar wind plasma. We used the WSO (Wilcox Solar Observatory at Stanford University) for the solar magnetic field input. By using the time-varying boundary condition, smooth variations of heliospheric MHD variables during the several Carrington solar rotation period are obtained. The simulation movie will show how the changes in the inner heliosphere observable by the ground-based instrument propagate outward and affects the outer heliosphere. The simulated MHD variables are compared with the Ulysses in-situ measurement data including ones made during its travel from the Earth to Jupiter for validation, and we obtain better agreements than with the simulation with fixed boundary conditions.

  19. Boundary transfer matrices and boundary quantum KZ equations

    NASA Astrophysics Data System (ADS)

    Vlaar, Bart

    2015-07-01

    A simple relation between inhomogeneous transfer matrices and boundary quantum Knizhnik-Zamolodchikov (KZ) equations is exhibited for quantum integrable systems with reflecting boundary conditions, analogous to an observation by Gaudin for periodic systems. Thus, the boundary quantum KZ equations receive a new motivation. We also derive the commutativity of Sklyanin's boundary transfer matrices by merely imposing appropriate reflection equations, in particular without using the conditions of crossing symmetry and unitarity of the R-matrix.

  20. Legal Issues Surrounding Safe Schools.

    ERIC Educational Resources Information Center

    Day, Reed B.

    This handbook provides an overview of legal issues pertaining to the safety of public schools. Following the introduction, chapter 2 describes the governance model and philosophy on which American education is based. Court decisions and federal and state legislation that mandate the right to a safe school are discussed in chapter 3. The fourth…

  1. Boundary control for a flexible manipulator based on infinite dimensional disturbance observer

    NASA Astrophysics Data System (ADS)

    Jiang, Tingting; Liu, Jinkun; He, Wei

    2015-07-01

    This paper focuses on disturbance observer and boundary control design for the flexible manipulator in presence of both boundary disturbance and spatially distributed disturbance. Taking the infinite-dimensionality of the flexural dynamics into account, this study proposes a partial differential equation (PDE) model. Since the spatially distributed disturbance is infinite dimensional, it cannot be compensated by the typical disturbance observer, which is designed by finite dimensional approach. To estimate the spatially distributed disturbance, we propose a novel infinite dimensional disturbance observer (IDDO). Applying the IDDO as a feedforward compensator, a boundary control scheme is designed to regulate the joint position and eliminate the elastic vibration simultaneously. Theoretical analysis validates the stability of both the proposed disturbance observer and the boundary controller. The performance of the closed-loop system is demonstrated by numerical simulations.

  2. Boundaries and Boundary Marks - Substantive Cultural Heritage of Extensive Importance

    NASA Astrophysics Data System (ADS)

    Waldhaeusl, P.; Koenig, H.; Mansberger, R.

    2015-08-01

    The Austrian Society for surveying and Geoinformation (ASG) has proposed to submit "Boundaries and Boundary Marks" for the UNESCO World Heritage title. It was time that boundaries, borders and limits of all types as well as ownership rights would find the proper attention in the global public. Landmarks symbolize the real property and the associated rights and obligations, in a figurative sense, the property generally and all legal limits. A democratic state of law is impossible at today's population density without a functioning land administration system with surveying and jurisdiction. As monumental World Heritage representatives of the geodetic artwork "Boundaries and Boundary Marks" are specifically proposed: remaining monuments of the original cadastral geodetic network, the first pan-Austrian surveying headquarters in Vienna, and a specific selection of outstanding boundary monuments. Landmarks are monuments to the boundaries which separate rights and obligations, but also connect the neighbors peacefully after written agreement. "And cursed be he who does not respect the boundaries" you wrote already 3000 years ago. Boundaries and Boundary Marks are a real thing; they all belong to the tangible or material heritage of human history. In this context also the intangible heritage is discussed. This refers to oral tradition and expressions, performing arts; social practices, rituals and festive events; as well as to knowledge and practices handling nature and the universe. "Boundaries and Boundary Marks" do not belong to it, but clearly to the material cultural world heritage. "Boundary and Boundary Marks" is proposed to be listed according to the criteria (ii),(iv),(vi).

  3. Safe Schools/Safe Communities: A Directory of Resources for Pennsylvania.

    ERIC Educational Resources Information Center

    Pennsylvania State Dept. of Education, Harrisburg.

    This document contains a directory of resources available in Pennsylvania to help achieve the goal of safe schools. Following a copy of the Safe Schools Act of 1993, nine sections list agencies that provide services and products under the headings of: conflict resolution/mediation, gangs, suicide, crisis response, family violence, diversity,…

  4. Lessons Learned from Safe Kids/Safe Streets. Juvenile Justice Bulletin

    ERIC Educational Resources Information Center

    Cronin, Roberta; Gragg, Frances; Schultz, Dana; Eisen, Karla

    2006-01-01

    This bulletin reports results from an evaluation of six sites of the Safe Kids/Safe Streets (SK/SS) program, which applies a comprehensive, collaborative approach to the child maltreatment field. The bulletin provides insights into collaboration building, systems reform, service options, and other strategies. Among the findings were that the SK/SS…

  5. Graph Theory-Based Technique for Isolating Corrupted Boundary Conditions in Continental-Scale River Network Hydrodynamic Simulation

    NASA Astrophysics Data System (ADS)

    Yu, C. W.; Hodges, B. R.; Liu, F.

    2017-12-01

    Development of continental-scale river network models creates challenges where the massive amount of boundary condition data encounters the sensitivity of a dynamic nu- merical model. The topographic data sets used to define the river channel characteristics may include either corrupt data or complex configurations that cause instabilities in a numerical solution of the Saint-Venant equations. For local-scale river models (e.g. HEC- RAS), modelers typically rely on past experience to make ad hoc boundary condition adjustments that ensure a stable solution - the proof of the adjustment is merely the sta- bility of the solution. To date, there do not exist any formal methodologies or automated procedures for a priori detecting/fixing boundary conditions that cause instabilities in a dynamic model. Formal methodologies for data screening and adjustment are a critical need for simulations with a large number of river reaches that draw their boundary con- dition data from a wide variety of sources. At the continental scale, we simply cannot assume that we will have access to river-channel cross-section data that has been ade- quately analyzed and processed. Herein, we argue that problematic boundary condition data for unsteady dynamic modeling can be identified through numerical modeling with the steady-state Saint-Venant equations. The fragility of numerical stability increases with the complexity of branching in river network system and instabilities (even in an unsteady solution) are typically triggered by the nonlinear advection term in Saint-Venant equations. It follows that the behavior of the simpler steady-state equations (which retain the nonlin- ear term) can be used to screen the boundary condition data for problematic regions. In this research, we propose a graph-theory based method to isolate the location of corrupted boundary condition data in a continental-scale river network and demonstrate its utility with a network of O(10^4) elements. Acknowledgement

  6. Communication and Culture in the Surgical Intensive Care Unit: Boundary Production and the Improvement of Patient Care.

    PubMed

    Conn, Lesley Gotlib; Haas, Barbara; Cuthbertson, Brian H; Amaral, Andre C; Coburn, Natalie; Nathens, Avery B

    2016-06-01

    This ethnography explores communication around critically ill surgical patients in three surgical intensive care units (ICUs) in Canada. A boundary framework is used to articulate how surgeons', intensivists', and nurses' communication practices shape and are shaped by their respective disciplinary perspectives and experiences. Through 50 hours of observations and 43 interviews, these health care providers are found to engage in seven communication behaviors that either mitigate or magnify three contested symbolic boundaries: expertise, patient ownership, and decisional authority. Where these boundaries are successfully mitigated, experiences of collaborative, high-quality patient care are produced; by contrast, boundary magnification produces conflict and perceptions of unsafe patient care. Findings reveal that high quality and safe patient care are produced through complex social and cultural interactions among surgeons, intensivists, and nurses that are also expressions of knowledge and power. This enhances our understanding of why current quality improvement efforts targeting communication may be ineffective. © The Author(s) 2015.

  7. 76 FR 12719 - Safe Schools/Healthy Students Program; Office of Safe and Drug-Free Schools; Safe Schools/Healthy...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-08

    ... official version of this document is the document published in the Federal Register. Free Internet access... DEPARTMENT OF EDUCATION Safe Schools/Healthy Students Program; Office of Safe and Drug- Free... telecommunications device for the deaf (TDD), call the Federal Relay Service (FRS), toll free, at 1-800-877-8339...

  8. A review of evidence for safe abortion care.

    PubMed

    Kapp, Nathalie; Whyte, Patti; Tang, Jennifer; Jackson, Emily; Brahmi, Dalia

    2013-09-01

    The provision of safe abortion services to women who need them has the potential to drastically reduce or eliminate maternal deaths due to unsafe abortion. The World Health Organization recently updated its evidence-based guidance for safe and effective clinical practices using data from systematic reviews of the literature. Systematic reviews pertaining to the evidence for safe abortion services, from pre-abortion care, medical and surgical methods of abortion and post-abortion care were evaluated for relevant outcomes, primarily those relating to safety, effectiveness and women's preference. Sixteen systematic reviews were identified and evaluated. The available evidence does not support the use of pre-abortion ultrasound to increase safety. Routine use of cervical preparation with osmotic dilators, mifepristone or misoprostol after 14 weeks gestation reduces complications; at early gestational ages, surgical abortions have very few complications. Prophylactic antibiotics result in lower rates of post-surgical abortion infection. Pain medication such as non-steroidal anti-inflammatories should be offered to women undergoing abortion procedures; acetaminophen, however, is not effective in reducing pain. Women who are eligible should be offered a choice between surgical (vacuum aspiration or dilation and evacuation) and medical methods (mifepristone and misoprostol) of abortion when possible. Modern methods of contraception can be safely initiated immediately following abortion procedures. Evidence-based guidelines assist health care providers and policymakers to utilize the best data available to provide safe abortion care and prevent the millions of deaths and disabilities that result from unsafe abortion. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Characterization of geostationary particle signatures based on the 'injection boundary' model

    NASA Technical Reports Server (NTRS)

    Mauk, B. H.; Meng, C.-I.

    1983-01-01

    A simplified analytical procedure is used to characterize the details of geostationary particle signatures, in order to lend support to the 'injection boundary' concept. The signatures are generated by the time-of-flight effects evolving from an initial sharply defined, double spiraled boundary configuration. Complex and highly variable dispersion patterns often observed by geostationary satellites are successfully reproduced through the exclusive use of the most fundamental convection configuration characteristics. Many of the details of the patterns have not been previously presented. It is concluded that most of the dynamical dispersion features can be mapped to the double spiral boundary without further ad hoc assumptions, and that predicted and observed dispersion patterns exhibit symmetries distinct from those associated with the quasi-stationary particle convection patterns.

  10. Safe pill-dispensing.

    PubMed

    Testa, Massimiliano; Pollard, John

    2007-01-01

    Each patient is supplied with a smart-card containing a Radio Frequency IDentification (RFID) chip storing a unique identification code. The patient places the Smart-card on a pill-dispenser unit containing an RFID reader. The RFID chip is read and the code sent to a Base-station via a wireless Bluetooth link. A database containing both patient details and treatment information is queried at the Base-station using the RFID as the search key. The patient's treatment data (i.e., drug names, quantities, time, etc.) are retrieved and sent back to the pill-dispenser unit via Bluetooth. Appropriate quantities of the required medications are automatically dispensed, unless the patient has already taken his/her daily dose. Safe, confidential communication and operation is ensured.

  11. Safe syringe disposal is related to safe syringe access among HIV-positive injection drug users.

    PubMed

    Coffin, Phillip O; Latka, Mary H; Latkin, Carl; Wu, Yingfeng; Purcell, David W; Metsch, Lisa; Gomez, Cynthia; Gourevitch, Marc N

    2007-09-01

    We evaluated the effect of syringe acquisition on syringe disposal among HIV-positive injection drug users (IDUs) in Baltimore, New York City, and San Francisco (N = 680; mean age 42 years, 62% male, 59% African-American, 21% Hispanic, 12% White). Independent predictors of safe disposal were acquiring syringes through a safe source and ever visiting a syringe exchange program. Weaker predictors included living in San Francisco, living in the area longer, less frequent binge drinking, injecting with an HIV+ partner, peer norms supporting safe injection, and self-empowerment. Independent predictors of safe "handling"-both acquiring and disposing of syringes safely-also included being from New York and being older. HIV-positive IDUs who obtain syringes from a safe source are more likely to safely dispose; peer norms contribute to both acquisition and disposal. Interventions to improve disposal should include expanding sites of safe syringe acquisition while enhancing disposal messages, alternatives, and convenience.

  12. Identifying phase-space boundaries with Voronoi tessellations

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

    Debnath, Dipsikha; Gainer, James S.; Kilic, Can

    Determining the masses of new physics particles appearing in decay chains is an important and longstanding problem in high energy phenomenology. Recently it has been shown that these mass measurements can be improved by utilizing the boundary of the allowed region in the fully differentiable phase space in its full dimensionality. Here in this paper we show that the practical challenge of identifying this boundary can be solved using techniques based on the geometric properties of the cells resulting from Voronoi tessellations of the relevant data. The robust detection of such phase-space boundaries in the data could also be usedmore » to corroborate a new physics discovery based on a cut-and-count analysis.« less

  13. Identifying phase-space boundaries with Voronoi tessellations

    DOE PAGES

    Debnath, Dipsikha; Gainer, James S.; Kilic, Can; ...

    2016-11-24

    Determining the masses of new physics particles appearing in decay chains is an important and longstanding problem in high energy phenomenology. Recently it has been shown that these mass measurements can be improved by utilizing the boundary of the allowed region in the fully differentiable phase space in its full dimensionality. Here in this paper we show that the practical challenge of identifying this boundary can be solved using techniques based on the geometric properties of the cells resulting from Voronoi tessellations of the relevant data. The robust detection of such phase-space boundaries in the data could also be usedmore » to corroborate a new physics discovery based on a cut-and-count analysis.« less

  14. Microstructural characterization of an SA508–309L/308L–316L domestic dissimilar metal welded safe-end joint

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

    Ming, Hongliang; Zhang, Zhiming; Wang, Jianqiu, E-mail: wangjianqiu@imr.ac.cn

    2014-11-15

    The microstructure of an SA508–309L/308L–316L domestic dissimilar metal welded safe-end joint was characterized in this work by optical microscopy, scanning electron microscopy (with electron back scattering diffraction) and micro-hardness testing. Epitaxial growth and competitive growth are evident in the 308L–316L fusion boundary regions. A martensite layer, carbon-depleted zones, and type-II and type-I boundaries are found in the SA508–309L fusion boundary regions, while only martensite and austenite mixed zones are observed in the SA508–308L fusion boundary regions. The microstructure near the fusion boundary and the microstructure transition in the SA508 heat affected zone are quite complex. Both for SA508–309L/308L and 308L–316L,more » the highest residual strain is located on the outside of the weldment. The residual strain and the grain boundary character distribution change with increasing distance from the fusion boundary in the heat affected zone of 316L. Micro-hardness measurements also reveal non-uniform mechanical properties across the weldment. - Highlights: • The microstructure of SA508 HAZ, especially near the FB, is very complex. • The outside of the dissimilar metal welded joint has the highest residual. • The micro-hardness distributions along the DMWJ are non-uniform.« less

  15. Installation Boundary Fence Replacement: Upland Areas: Environmental Assessment

    DTIC Science & Technology

    2004-05-27

    Moody Air Force Base, GA Environmental Assessment Installation Boundary Fence Replacement INSTALLATION BOUNDARY...347 CES/CEV),3485 Georgia Street,Moody AFB, GA ,31699 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES...Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 Moody Air Force Base, GA Environmental Assessment

  16. C-SAFE: A Computer-Delivered Sexual Health Promotion Program for Latinas.

    PubMed

    Klein, Charles H; Kuhn, Tamara; Altamirano, Midori; Lomonaco, Carmela

    2017-07-01

    This article describes the development and evaluation of C-SAFE (Sexual Awareness for Everyone), a computer-delivered sexual health promotion program for Latinas. We first describe the process of adapting an evidence-based, group-level intervention into an individually administered computer-delivered program. We then present the methods and results of a randomized control trial with 321 Latinas in California and Florida to test C-SAFE's preliminary efficacy in reducing sexual health risk. We found no statistically significant differences between the two conditions at a six-month follow-up in terms of sexual behaviors or attitudes toward sexually transmitted infections and condoms, although C-SAFE women reported fewer days in the past month when their mental health was not good (p = .02). C-SAFE condition women also reported more satisfaction than control condition women in their assessment of information presentation (on a scale of 1 = poor and 5 = excellent; C-SAFE = 4.45 vs. control = 4.25, p = .053) and having learned something new (C-SAFE = 95.1% vs. control = 79.3%, χ 2 < 0.001), with utility of content for Latinas approaching significance (C-SAFE = 4.50 vs. control = 4.31, p = .058). In conclusion we discuss the importance of teachable moments, matching of delivery modalities to implementation contexts, and possible directions for evidence-based sexual health promotion programs given the current sexual health landscape.

  17. Aqueous extracts of Mozambican plants as alternative and environmentally safe acid-base indicators.

    PubMed

    Macuvele, Domingos Lusitaneo Pier; Sithole, Gerre Zebedias Samo; Cesca, Karina; Macuvele, Suzana Lília Pinare; Matsinhe, Jonas Valente

    2016-06-01

    Indicators are substances that change color as the pH of the medium. Many of these substances are dyes of synthetic origin. The mulala plant (Euclea natalensis), which roots are commonly used by rural communities for their oral hygiene, and roseira (Hibiscus rosa-sinensis), an ornamental plant, are abundant in Mozambique. Currently, synthetic acid-base indicators are most commonly used but have environmental implications and, on the other hand, are expensive products, so the demand for natural indicators started. This study investigated the applicability of aqueous extracts of H. rosa-sinensis and E. natalensis as acid-base indicators. Ground on this work, the extracts can be used as acid-base indicators. On the basis of the absorption spectroscopy in both the UV-Vis region and previous studies, it was possible to preliminarily pinpoint anthocyanins and naphthoquinones as responsible for the shifting of colors depending on the pH range of aqueous extracts of H. rosa-sinensis and E. natalensis. These natural indicators are easily accessible, inexpensive, easy to extract, environmentally safe, and locally available.

  18. Boundary states at reflective moving boundaries

    NASA Astrophysics Data System (ADS)

    Acosta Minoli, Cesar A.; Kopriva, David A.

    2012-06-01

    We derive and evaluate boundary states for Maxwell's equations, the linear, and the nonlinear Euler gas-dynamics equations to compute wave reflection from moving boundaries. In this study we use a Discontinuous Galerkin Spectral Element method (DGSEM) with Arbitrary Lagrangian-Eulerian (ALE) mapping for the spatial approximation, but the boundary states can be used with other methods, like finite volume schemes. We present four studies using Maxwell's equations, one for the linear Euler equations, and one more for the nonlinear Euler equations. These are: reflection of light from a plane mirror moving at constant velocity, reflection of light from a moving cylinder, reflection of light from a vibrating mirror, reflection of sound from a plane wall and dipole sound generation by an oscillating cylinder in an inviscid flow. The studies show that the boundary states preserve spectral convergence in the solution and in derived quantities like divergence and vorticity.

  19. The Right to Food and the Planetary Boundaries framework.

    PubMed

    Heesterman, Wiebina

    2017-03-01

    The 'Right to Food' is a legal entitlement owed to all human beings established in international law more than half a century ago. Fulfilment of the right has been entrusted to states parties to the 1966 International Covenant on Economic, Social and Cultural Rights (ICESCR). However, in practice, the right is often breached because of hostility or indifference from individuals or institutions refusing access to provisions, or because of vicissitudes of nature. Adverse impacts due to human interference in natural processes are increasingly noticeable in the area of food production. These processes have been classified into nine distinct categories, all of which need be kept within certain margins, so-called 'Planetary Boundaries', which delineate a safe operating space for humanity. This paper discusses the impact each of these human-induced developments has on the provision of food as well as the other way round and what the consequences would be if the boundaries were exceeded. Yet there are means of keeping the worst consequences of most of these processes at bay. The paper explores some of these.

  20. An iterative kernel based method for fourth order nonlinear equation with nonlinear boundary condition

    NASA Astrophysics Data System (ADS)

    Azarnavid, Babak; Parand, Kourosh; Abbasbandy, Saeid

    2018-06-01

    This article discusses an iterative reproducing kernel method with respect to its effectiveness and capability of solving a fourth-order boundary value problem with nonlinear boundary conditions modeling beams on elastic foundations. Since there is no method of obtaining reproducing kernel which satisfies nonlinear boundary conditions, the standard reproducing kernel methods cannot be used directly to solve boundary value problems with nonlinear boundary conditions as there is no knowledge about the existence and uniqueness of the solution. The aim of this paper is, therefore, to construct an iterative method by the use of a combination of reproducing kernel Hilbert space method and a shooting-like technique to solve the mentioned problems. Error estimation for reproducing kernel Hilbert space methods for nonlinear boundary value problems have yet to be discussed in the literature. In this paper, we present error estimation for the reproducing kernel method to solve nonlinear boundary value problems probably for the first time. Some numerical results are given out to demonstrate the applicability of the method.

  1. The boundary characteristics of lucid dreamers.

    PubMed

    Galvin, F

    1990-06-01

    Based on the previously established personality correlates of frequent lucid dreaming and frequent nightmare dreaming, several hypotheses were generated regarding the boundary characteristics of these dreamers relative to each other and to a control group of non-lucid and comparatively nightmare-free dreamers. The data from Hartmann's Boundary Questionnaire obtained from 40 subjects in each dreamer group (who were individually matched for sex, age, and background as far as possible) were analyzed. The results of the study give evidence that lucid dreamers have "thin" boundaries in many of the same senses that nightmare sufferers do, but can be differentiated from nightmare dreamers by the greater degree of coherence of their psychological sense of self as measured on the Self-Coherence Subscale of the Boundary Questionnaire. The suggestion is made that, given the similarity of "thin" boundaries, perhaps nightmare sufferers could become lucid dreamers and possibly resolve their nightmare condition while in the dream state.

  2. Boundaries of dreams, boundaries of dreamers: thin and thick boundaries as a new personality measure.

    PubMed

    Hartmann, E

    1989-11-01

    Previous work by the author and his collaborators on frequent nightmare sufferers demonstrated that these people had striking personality characteristics which could be called "thin boundaries" in a number of different senses. In order to measure thin and thick boundaries, a 145-item questionnaire, the Boundary Questionnaire, has been developed which has now been taken by over 1,000 persons. Preliminary results are presented indicating that, as predicted a priori, several new groups of nightmare sufferers and groups of art students scored usually "thin," whereas a group of naval officers had usually "thick" boundaries. Overall, thinness on the Boundary Questionnaire correlated highly positively (r = .40) with frequency of dream recall and also significantly (r = .16) with length of sleep.

  3. Safe Disposal of Highly Reactive Chemicals.

    ERIC Educational Resources Information Center

    Lunn, George; Sansone, Eric B.

    1994-01-01

    Provides specific procedures for the disposal of a variety of highly reactive chemicals and reports the results of a study of their safe disposal. Disposal of some problematic sulfur-containing compounds are included. Procedures are based on a combination of literature review and author development. (LZ)

  4. Atomistic modeling of grain boundary behavior under shear conditions in magnesium and magnesium-based binary alloys

    NASA Astrophysics Data System (ADS)

    Nahhas, M. K.; Groh, S.

    2018-02-01

    In this study, the structure, the energetic, and the strength of a { 10 1 bar 1 } < 11 2 bar 0 > symmetric tilt grain boundary in magnesium and magnesium binary alloys were analyzed in the framework of (semi-)empirical potentials. Following a systematic investigation of the transferability and accuracy of the interatomic potentials, atomistic calculations of the grain boundary energy, the grain boundary sliding energy, and the grain boundary strength were performed in pure magnesium and in binary MgX alloys (X = Al, Ca, Gd, Li, Sn, Y, Ag, Nd, and Pb). The data gained in this study were analyzed to identify the most critical material parameters controlling the strength of the grain boundary, and their consequence on atomic shuffling motions occurring at the grain boundary. From the methodology perspective, the role of in-plane and out-of plane relaxation on the grain boundary sliding energy curves was investigated. In pure magnesium, the results showed that in-plane relaxation is critical in activating b2{ 10 1 bar 1 } twinning dislocation resulting in grain boundary migration. In the alloy systems, however, grain boundary migration was disabled as a consequence of the pinning of the grain boundary by segregated elements. Finally, while the grain boundary energy, the shape of the grain boundary sliding energy curves, and the grain boundary sliding energy are critical parameters controlling the grain boundary strength in pure magnesium, only the grain boundary energy and the segregation energy of the alloying elements at the grain boundary were identified as critical material parameters in the alloys system.

  5. Deleterious localized stress fields: the effects of boundaries and stiffness tailoring in anisotropic laminated plates

    PubMed Central

    Weaver, P. M.

    2016-01-01

    The safe design of primary load-bearing structures requires accurate prediction of stresses, especially in the vicinity of geometric discontinuities where deleterious three-dimensional stress fields can be induced. Even for thin-walled structures significant through-thickness stresses arise at edges and boundaries, and this is especially precarious for laminates of advanced fibre-reinforced composites because through-thickness stresses are the predominant drivers in delamination failure. Here, we use a higher-order equivalent single-layer model derived from the Hellinger–Reissner mixed variational principle to examine boundary layer effects in laminated plates comprising constant-stiffness and variable-stiffness laminae and deforming statically in cylindrical bending. The results show that zigzag deformations, which arise due to layerwise differences in the transverse shear moduli, drive boundary layers towards clamped edges and are therefore critically important in quantifying localized stress gradients. The relative significance of the boundary layer scales with the degree of layerwise anisotropy and the thickness to characteristic length ratio. Finally, we demonstrate that the phenomenon of alternating positive and negative transverse shearing deformation through the thickness of composite laminates, previously only observed at clamped boundaries, can also occur at other locations as a result of smoothly varying the material properties over the in-plane dimensions of the laminate. PMID:27843401

  6. Propulsion of helical flagella near boundaries

    NASA Astrophysics Data System (ADS)

    Rodenborn, Bruce; Giesbrecht, Grant; Ni, Katha; Vock, Isaac

    The presence of nearby boundaries is known to have dramatic effects on the swimming behavior of microorganisms because of the no-slip condition at the boundary. Microorganisms that use a helical flagellum experience forces both along the axis of the helix and in the direction perpendicular to the axis. These low Reynolds number boundary effects have primarily been studied using live bacteria and using numerical simulations. However, small scale measurements give limited information about the forces and torques on the microorganisms. Furthermore, numerical studies are approximate because they have generally used Stokeslet-based simulations with image Stokeslets to represent the effects of the boundaries. Instead, we directly measure the propulsion of macroscopic helical flagella with diameter 12 mm using a fluid with viscosity 105 times that of water to ensure the Reynolds number in the experiments is much less than unity, just as for bacteria. We measure the parallel and perpendicular forces as a function of boundary distance to determine the nonzero elements of the propulsive matrix for axial rotation near a boundary. We then compare our results to the theory and simulations of Lauga et al. and to biological measurements.

  7. Stabilizing the boundary between US politics and science: the role of the Office of Technology Transfer as a boundary organization.

    PubMed

    Guston, D H

    1999-02-01

    The sociological study of boundary-work and the political-ecomomic approach of principal-agent theory can be complementary ways of examining the relationship between society and science: boundary-work provides the empirical nuance to the principal-agent scheme, and principal-agent theory provides structure to the thick boundary description. This paper motivates this complementarity to examine domestic technology transfer in the USA from the intramural laboratories of the US National Institutes of Health (NIH). It casts US policy for technology transfer in the principal-agent framework, in which politicians attempt to manage the moral hazard of the productivity of research by providing specific incentives to the agents for engaging in measurable research-based innovation. Such incentives alter the previously negotiated boundary between politics and science. The paper identifies the crucial role of the NIH Office of Technology Transfer (OTT) as a boundary organization, which medicates the new boundary negotiations in its routine work, and stabilizes the boundary by performing successfully as an agent for both politicians and scientists. The paper hypothesizes that boundary organizations like OTT are general phenomena at the boundary between politics and science.

  8. The Permian-Triassic boundary & mass extinction in China

    USGS Publications Warehouse

    Metcalfe, I.; Nicoll, R.S.; Mundil, R.; Foster, C.; Glen, J.; Lyons, J.; Xiaofeng, W.; Cheng-Yuan, W.; Renne, P.R.; Black, L.; Xun, Q.; Xiaodong, M.

    2001-01-01

    The first appearance of Hindeodus parvus (Kozur & Pjatakova) at the Permian-Triassic (P-T) GSSP level (base of Bed 27c) at Meishan is here confirmed. Hindeodus changxingensis Wang occurs from Beds 26 to 29 at Meishan and appears to be restricted to the narrow boundary interval immediately above the main mass extinction level in Bed 25. It is suggested that this species is therefore a valuable P-T boundary interval index taxon. Our collections from the Shangsi section confirm that the first occurrence of Hindeodus parvus in that section is about 5 in above the highest level from which a typical Permian fauna is recovered. This may suggest that that some section may be missing at Meishan. The age of the currently defined Permian-Triassic Boundary is estimated by our own studies and a reassessment of previous worker's data at c. 253 Ma, slightly older than our IDTIMS 206Pb/238U age of 252.5 ??0.3 Ma for Bed 28, just 8 cm above the GSSP boundary (Mundil et al., 2001). The age of the main mass extinction, at the base of Bed 25 at Meishan, is estimated at slightly older than 254 Ma based on an age of >254 Ma for the Bed 25 ash. Regardless of the absolute age of the boundary, it is evident that the claimed <165,000 y short duration for the negative carbon isotope excursion at the P-T boundary (Bowring et al., 1998) cannot be confirmed. Purportedly extraterrestrial fullerenes at the boundary (Hecker et al., 2001) have equivocal significance due to their chronostratigraphic non-uniqueness and their occurrence in a volcanic ash.

  9. Safe Manual Jettison

    NASA Technical Reports Server (NTRS)

    Barton, Jay

    2008-01-01

    In space, the controlled release of certain cargoes is no less useful than the maritime jettisons from which they take their name but is also much more dangerous. Experience has shown that jettisons can be performed safely, but the process is complicated with the path to performing a jettison taking months or even years. In the background, time is also required to write procedures, train the crew, configure the vehicle, and many other activities. This paper outlines the current process used by the National Aeronautics and Space Administration (NASA) for manual jettisons, detailing the methods used to assure that the jettisons and the jettisoned objects are as safe as achievable and that the crew is adequately trained to be able to affect the safe jettison. The goal of this paper is not only to capture what it takes to perform safe jettisons in the near Earth environment but to extrapolate this knowledge to future space exploration scenarios that will likely have Extravehicular Activity (EVA) and International Partner (IP) interfaces.

  10. Grain-boundary unzipping by oxidation in polycrystalline graphene

    NASA Astrophysics Data System (ADS)

    Alexandre, Simone; Lucio, Aline; Nunes, Ricardo

    2011-03-01

    The need for large-scale production of graphene will inevitably lead to synthesis of the polycrystalline material [1,2]. Understanding the chemical, mechanical, and electronic properties of grain boundaries in graphene polycrystals will be crucial for the development of graphene-based electronics. Oxidation of this material has been suggested to lead to graphene ribbons, by the oxygen-driven unzipping mechanism. A cooperative-strain mechanism, based on the formation of epoxy groups along lines of parallel bonds in the hexagons of graphene's honeycomb lattice, was proposed to explain the unzipping effect in bulk graphene In this work we employ ab initio calculations to study the oxidation of polycrystalline graphene by chemisorption of oxygen at the grain boundaries. Our results indicate that oxygen tends to segregate at the boundaries, and that the unzipping mechanism is also operative along the grain boundaries, despite the lack of the parallel bonds due to the presence of fivefold and sevenfold carbon rings along the boundary core. We acknowledge support from the Brazilian agencies: CNPq, Fapemig, and INCT-Materiais de Carbono.

  11. Safe mobility for elderly drivers--considerations based on expert and self-assessment.

    PubMed

    Broberg, Thomas; Dukic Willstrand, Tania

    2014-05-01

    To further understand the needs of the growing population of elderly drivers and create solutions for safe mobility it is important to understand the driving scenarios and aspects in day to day traffic that may be of challenge for this group. More so, individual differences in how drivers perceive their own driving ability may have an effect on how individuals limit their mobility and/or increase their exposure to risk situations, with a potential negative effect on safety. In this study two sets of assessments have been used in order to identify scenarios and aspects needing consideration in creating safe mobility for elderly drivers; an expert assessment using on-road driving together with assessments through semi structured in-depth interviews. This combination also enables categorisation of the drivers, comparing their own perception of their driving performance with the expert assessment based on actual on-road driving. Four different categories of drivers were identified: adequate (positive), over, under and adequate (negative) estimators. A number of important aspects were identified in the study. Adapting speed to the situation and driving too fast, especially on straight roads in the city, is one aspect. Seeking the attention of other road users at intersections and roundabouts is another important consideration identified. Awareness of difficulties related to speed adaptation and attention was low amongst all the driver categories. However, a difference in attitude was seen in the categories with a more humble and acceptant attitude amongst the adequate and under estimator groups, as compared to the over estimators suggesting that the aspect of attitudes is another important factor for consideration. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Boundary issues

    NASA Astrophysics Data System (ADS)

    Townsend, Alan R.; Porder, Stephen

    2011-03-01

    can (and ultimately must) learn to capture and re-use P in human and animal wastes. And, as Carpenter and Bennett highlight, inequities in P availability across world regions are not just a problem, they are an opportunity: transfers from P-rich to P-poor regions could simultaneously reduce environmental and food security risks. Above all, Carpenter and Bennett's analyses highlight the need for new management strategies that better target not only P's environmental risks, but also recognize the element's standing as an irreplaceable resource. Human society has been built from the massive alteration of four global biogeochemical cycles (C, N, H2O and P). We can replace carbon-based fuels, plant legumes in lieu of Haber-Bosch-based N fixation, and the rain will still fall. But for P, there is neither substitute nor renewal. Without an almost closed loop between fertilizer application, food consumption, and waste management, society could solve the remainder of the environmental threats Rockström and colleagues identify, and still be facing a bleak future. References Carpenter S R and Bennett E M 2011 Reconsideration of the planetary boundary for phosphorus Environ. Res. Lett. 6 014009 Childers C L, Corman J, Edwards M and Elser J J 2011 Sustainability challenges of phosphorus and food: solutions from closing the human phosphorus cycle BioScience 61 117-24 Cordell D, Drangert J-O and White S 2009 The story of phosphorus: Global food security and food for thought global Environmental Change 19 292-305 Diamond J 2005 Collapse: How Societies Choose to Fail or Succeed (New York: Viking) Engelhardt H T and Caplan A L (ed) 1987 Scientific Controversies: Case Studies in the Resolution and Closure of Disputes in Science and Technology (New York: Cambridge University Press) Filippelli G M 2008 The global phosphorus cycle: Past, present, and future Elements 4 89-95 Galloway J N, Townsend A R, Erisman J W, Bekunda M, Cai Z C, Freney J R, Martinelli L A, Seitzinger S P and Sutton M

  13. Towards Natural Transition in Compressible Boundary Layers

    DTIC Science & Technology

    2016-06-29

    Behaviour of a natural laminar flow aerofoil in flight through atmospheric turbulence. Journal of Fluid Mechanics, 767:394–429, 003 2015. [70] O...DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited See report Wave packet, compressible boundary layer, subsonic flow ...Base flow generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 3.1.1 Boundary layer profiles

  14. Connectivity as an alternative to boundary integral equations: Construction of bases

    PubMed Central

    Herrera, Ismael; Sabina, Federico J.

    1978-01-01

    In previous papers Herrera developed a theory of connectivity that is applicable to the problem of connecting solutions defined in different regions, which occurs when solving partial differential equations and many problems of mechanics. In this paper we explain how complete connectivity conditions can be used to replace boundary integral equations in many situations. We show that completeness is satisfied not only in steady-state problems such as potential, reduced wave equation and static and quasi-static elasticity, but also in time-dependent problems such as heat and wave equations and dynamical elasticity. A method to obtain bases of connectivity conditions, which are independent of the regions considered, is also presented. PMID:16592522

  15. Safely Enabling UAS Operations in Low-Altitude Airspace

    NASA Technical Reports Server (NTRS)

    Kopardekar, Parimal H.

    2016-01-01

    Flexibility where possible, and structure where necessary. Consider the needs of national security, safe airspace operations, economic opportunities, and emerging technologies. Risk-based approach based on population density, assets on the ground, density of operations, etc. Digital, virtual, dynamic, and as needed UTM services to manage operations.

  16. The fire-safe cigarette: a burn prevention tool.

    PubMed

    Barillo, D J; Brigham, P A; Kayden, D A; Heck, R T; McManus, A T

    2000-01-01

    Cigarettes are the most common ignition source for fatal house fires, which cause approximately 29% of the fire deaths in the United States. A common scenario is the delayed ignition of a sofa, chair, or mattress by a lit cigarette that is forgotten or dropped by a smoker whose alertness is impaired by alcohol or medication. Cigarettes are designed to continue burning when left unattended. If they are dropped on mattresses, upholstered furniture, or other combustible material while still burning, their propensity to start fires varies depending on the cigarette design and content. The term "fire-safe" has evolved to describe cigarettes designed to have a reduced propensity for igniting mattresses and upholstered furniture. Legislative interest in the development of fire-safe smoking materials has existed for more than 50 years. Studies that showed the technical and economic feasibility of commercial production of fire-safe cigarettes were completed more than 10 years ago. Despite this, commercial production of fire-safe smoking materials has not been undertaken. The current impasse relates to the lack of consensus on a uniform test method on which to base a standard for fire-safe cigarettes. Although the fire-safe cigarette is a potentially important burn prevention tool, commercial production of such cigarettes will not occur until a standard against which fire-starting performance can be measured has been mandated by law at the state or federal level. The burn care community can play a leadership role in such legislative efforts.

  17. Exploring the planetary boundary for chemical pollution.

    PubMed

    Diamond, Miriam L; de Wit, Cynthia A; Molander, Sverker; Scheringer, Martin; Backhaus, Thomas; Lohmann, Rainer; Arvidsson, Rickard; Bergman, Åke; Hauschild, Michael; Holoubek, Ivan; Persson, Linn; Suzuki, Noriyuki; Vighi, Marco; Zetzsch, Cornelius

    2015-05-01

    Rockström et al. (2009a, 2009b) have warned that humanity must reduce anthropogenic impacts defined by nine planetary boundaries if "unacceptable global change" is to be avoided. Chemical pollution was identified as one of those boundaries for which continued impacts could erode the resilience of ecosystems and humanity. The central concept of the planetary boundary (or boundaries) for chemical pollution (PBCP or PBCPs) is that the Earth has a finite assimilative capacity for chemical pollution, which includes persistent, as well as readily degradable chemicals released at local to regional scales, which in aggregate threaten ecosystem and human viability. The PBCP allows humanity to explicitly address the increasingly global aspects of chemical pollution throughout a chemical's life cycle and the need for a global response of internationally coordinated control measures. We submit that sufficient evidence shows stresses on ecosystem and human health at local to global scales, suggesting that conditions are transgressing the safe operating space delimited by a PBCP. As such, current local to global pollution control measures are insufficient. However, while the PBCP is an important conceptual step forward, at this point single or multiple PBCPs are challenging to operationalize due to the extremely large number of commercial chemicals or mixtures of chemicals that cause myriad adverse effects to innumerable species and ecosystems, and the complex linkages between emissions, environmental concentrations, exposures and adverse effects. As well, the normative nature of a PBCP presents challenges of negotiating pollution limits amongst societal groups with differing viewpoints. Thus, a combination of approaches is recommended as follows: develop indicators of chemical pollution, for both control and response variables, that will aid in quantifying a PBCP(s) and gauging progress towards reducing chemical pollution; develop new technologies and technical and social

  18. The complex variable boundary element method: Applications in determining approximative boundaries

    USGS Publications Warehouse

    Hromadka, T.V.

    1984-01-01

    The complex variable boundary element method (CVBEM) is used to determine approximation functions for boundary value problems of the Laplace equation such as occurs in potential theory. By determining an approximative boundary upon which the CVBEM approximator matches the desired constant (level curves) boundary conditions, the CVBEM is found to provide the exact solution throughout the interior of the transformed problem domain. Thus, the acceptability of the CVBEM approximation is determined by the closeness-of-fit of the approximative boundary to the study problem boundary. ?? 1984.

  19. An ethics safe harbor for international genomics research?

    PubMed Central

    2013-01-01

    Background Genomics research is becoming increasingly globally connected and collaborative, contesting traditional ethical and legal boundaries between global and local research practice. As well, global data-driven genomics research holds great promise for health discoveries. Yet, paradoxically, current research ethics review systems around the world challenge potential improvements in human health from such research and thus undermine respect for research participants. Case reports illustrate that the current system is costly, fragmented, inefficient, inadequate, and inconsistent. There is an urgent need to improve the governance system of ethics review to enable secure and seamless genomic and clinical data sharing across jurisdictions. Discussion Building on the international privacy 'safe harbor’ model that was developed following the adoption of the European Privacy Directive, we propose an international infrastructure. The goal is to create a streamlined and harmonized ethics governance system for international, data-driven genomics research projects. The proposed 'Safe Harbor Framework for International Ethics Equivalency’ would consist in part of an agency supporting an International Federation for Ethics Review (IFER), formed by a voluntary agreement among countries, granting agencies, philanthropies, institutions, and healthcare, patient advocacy, and research organizations. IFER would be both a central ethics review body and also a forum for review and follow-up of policies concerning ethics norms for international genomics research projects. It would be built on five principle elements: (1) registration; (2) compliance review; (3) recognition; (4) monitoring and enforcement; and (5) public participation. Summary A Safe Harbor Framework for International Ethics Equivalency would create many benefits for researchers, countries, and the general public, and may eventually have application beyond genomics to other areas of biomedical research that

  20. Solving Fluid Structure Interaction Problems with an Immersed Boundary Method

    NASA Technical Reports Server (NTRS)

    Barad, Michael F.; Brehm, Christoph; Kiris, Cetin C.

    2016-01-01

    An immersed boundary method for the compressible Navier-Stokes equations can be used for moving boundary problems as well as fully coupled fluid-structure interaction is presented. The underlying Cartesian immersed boundary method of the Launch Ascent and Vehicle Aerodynamics (LAVA) framework, based on the locally stabilized immersed boundary method previously presented by the authors, is extended to account for unsteady boundary motion and coupled to linear and geometrically nonlinear structural finite element solvers. The approach is validated for moving boundary problems with prescribed body motion and fully coupled fluid structure interaction problems. Keywords: Immersed Boundary Method, Higher-Order Finite Difference Method, Fluid Structure Interaction.

  1. Safe transport of radioactive materials in Egypt

    NASA Astrophysics Data System (ADS)

    El-Shinawy, Rifaat M. K.

    1994-07-01

    In Egypt the national regulations for safe transport of radioactive materials (RAM) are based on the International Atomic Energy Agency (IAEA) regulations. In addition, regulations for the safe transport of these materials through the Suez Canal (SC) were laid down by the Egyptian Atomic Energy Authority (EAEA) and the Suez Canal Authority (SCA). They are continuously updated to meet the increased knowledge and the gained experience. The technical and protective measures taken during transport of RAM through SC are mentioned. Assessment of the impact of transporting radioactive materials through the Suez Canal using the INTERTRAN computer code was carried out in cooperation with IAEA. The transported activities and empty containers, the number of vessels carrying RAM through the canal from 1963 to 1991 and their nationalities are also discussed. The protective measures are mentioned.A review of the present situation of the radioactive wastes storage facilities at the Atomic Energy site at Inshas is given along with the regulation for safe transportation and disposal of radioactive wastes

  2. Smart aircraft fastener evaluation (SAFE) system: a condition-based corrosion detection system for aging aircraft

    NASA Astrophysics Data System (ADS)

    Schoess, Jeffrey N.; Seifert, Greg; Paul, Clare A.

    1996-05-01

    The smart aircraft fastener evaluation (SAFE) system is an advanced structural health monitoring effort to detect and characterize corrosion in hidden and inaccessible locations of aircraft structures. Hidden corrosion is the number one logistics problem for the U.S. Air Force, with an estimated maintenance cost of $700M per year in 1990 dollars. The SAFE system incorporates a solid-state electrochemical microsensor and smart sensor electronics in the body of a Hi-Lok aircraft fastener to process and autonomously report corrosion status to aircraft maintenance personnel. The long-term payoff for using SAFE technology will be in predictive maintenance for aging aircraft and rotorcraft systems, fugitive emissions applications such as control valves, chemical pipeline vessels, and industrial boilers. Predictive maintenance capability, service, and repair will replace the current practice of scheduled maintenance to substantially reduce operational costs. A summary of the SAFE concept, laboratory test results, and future field test plans is presented.

  3. Boundary-Layer Receptivity and Integrated Transition Prediction

    NASA Technical Reports Server (NTRS)

    Chang, Chau-Lyan; Choudhari, Meelan

    2005-01-01

    The adjoint parabold stability equations (PSE) formulation is used to calculate the boundary layer receptivity to localized surface roughness and suction for compressible boundary layers. Receptivity efficiency functions predicted by the adjoint PSE approach agree well with results based on other nonparallel methods including linearized Navier-Stokes equations for both Tollmien-Schlichting waves and crossflow instability in swept wing boundary layers. The receptivity efficiency function can be regarded as the Green's function to the disturbance amplitude evolution in a nonparallel (growing) boundary layer. Given the Fourier transformed geometry factor distribution along the chordwise direction, the linear disturbance amplitude evolution for a finite size, distributed nonuniformity can be computed by evaluating the integral effects of both disturbance generation and linear amplification. The synergistic approach via the linear adjoint PSE for receptivity and nonlinear PSE for disturbance evolution downstream of the leading edge forms the basis for an integrated transition prediction tool. Eventually, such physics-based, high fidelity prediction methods could simulate the transition process from the disturbance generation through the nonlinear breakdown in a holistic manner.

  4. Strategies and challenges for safe injection practice in developing countries.

    PubMed

    Gyawali, Sudesh; Rathore, Devendra Singh; Shankar, P Ravi; Kumar, Kc Vikash

    2013-01-01

    Injection is one of the important health care procedures used globally to administer drugs. Its unsafe use can transmit various blood borne pathogens. This article aims to review the history and status of injection practices, its importance, interventions and the challenges for safe injection practice in developing countries. The history of injections started with the discovery of syringe in the early nineteenth century. Safe injection practice in developed countries was initiated in the early twentieth century but has not received adequate attention in developing countries. The establishment of "Safe Injection Global Network (SIGN)" was an milestone towards safe injection practice globally. In developing countries, people perceive injection as a powerful healing tool and do not hesitate to pay more for injections. Unsafe disposal and reuse of contaminated syringe is common. Ensuring safe injection practice is one of the greatest challenges for healthcare system in developing countries. To address the problem, interventions with active involvement of a number of stakeholders is essential. A combination of educational, managerial and regulatory strategies is found to be effective and economically viable. Rational and safe use of injections can save many lives but unsafe practice threatens life. Safe injection practice is crucial in developing countries. Evidence based interventions, with honest commitment and participation from the service provider, recipient and community with aid of policy makers are required to ensure safe injection practice.

  5. Strategies and challenges for safe injection practice in developing countries

    PubMed Central

    Gyawali, Sudesh; Rathore, Devendra Singh; Shankar, P Ravi; Kumar, KC Vikash

    2013-01-01

    Injection is one of the important health care procedures used globally to administer drugs. Its unsafe use can transmit various blood borne pathogens. This article aims to review the history and status of injection practices, its importance, interventions and the challenges for safe injection practice in developing countries. The history of injections started with the discovery of syringe in the early nineteenth century. Safe injection practice in developed countries was initiated in the early twentieth century but has not received adequate attention in developing countries. The establishment of “Safe Injection Global Network (SIGN)” was an milestone towards safe injection practice globally. In developing countries, people perceive injection as a powerful healing tool and do not hesitate to pay more for injections. Unsafe disposal and reuse of contaminated syringe is common. Ensuring safe injection practice is one of the greatest challenges for healthcare system in developing countries. To address the problem, interventions with active involvement of a number of stakeholders is essential. A combination of educational, managerial and regulatory strategies is found to be effective and economically viable. Rational and safe use of injections can save many lives but unsafe practice threatens life. Safe injection practice is crucial in developing countries. Evidence based interventions, with honest commitment and participation from the service provider, recipient and community with aid of policy makers are required to ensure safe injection practice. PMID:23662018

  6. The layer boundary effect on multi-layer mesoporous TiO 2 film based dye sensitized solar cells

    DOE PAGES

    Xu, Feng; Zhu, Kai; Zhao, Yixin

    2016-10-10

    Multi-layer mesoporous TiO 2 prepared by screen printing is widely used for fabrication of high-efficiency dye-sensitized solar cells (DSSCs). Here, we compare the three types of ~10 um thick mesoporous TiO 2 films, which were screen printed as 1-, 2- and 4-layers using the same TiO 2 nanocrystal paste. The layer boundary of the multi-layer mesoporous TiO 2 films was observed in the cross-section SEM. The existence of a layer boundary could reduce the photoelectron diffusion length with the increase of layer number. However, the photoelectron diffusion lengths of the Z907 dye sensitized solar cells based on these different layeredmore » mesoporous TiO 2 films are all longer than the film thickness. Consequently, the photovoltaic performance seems to have little dependence on the layer number of the multi-layer TiO 2 based DSSCs.« less

  7. The layer boundary effect on multi-layer mesoporous TiO 2 film based dye sensitized solar cells

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

    Xu, Feng; Zhu, Kai; Zhao, Yixin

    Multi-layer mesoporous TiO 2 prepared by screen printing is widely used for fabrication of high-efficiency dye-sensitized solar cells (DSSCs). Here, we compare the three types of ~10 um thick mesoporous TiO 2 films, which were screen printed as 1-, 2- and 4-layers using the same TiO 2 nanocrystal paste. The layer boundary of the multi-layer mesoporous TiO 2 films was observed in the cross-section SEM. The existence of a layer boundary could reduce the photoelectron diffusion length with the increase of layer number. However, the photoelectron diffusion lengths of the Z907 dye sensitized solar cells based on these different layeredmore » mesoporous TiO 2 films are all longer than the film thickness. Consequently, the photovoltaic performance seems to have little dependence on the layer number of the multi-layer TiO 2 based DSSCs.« less

  8. Usability and Feasibility of an Internet-Based Virtual Pedestrian Environment to Teach Children to Cross Streets Safely

    PubMed Central

    Schwebel, David C.; McClure, Leslie A.; Severson, Joan

    2013-01-01

    Child pedestrian injury is a preventable global health challenge. Successful training efforts focused on child behavior, including individualized streetside training and training in large virtual pedestrian environments, are laborious and expensive. This study considers the usability and feasibility of a virtual pedestrian environment “game” application to teach children safe street-crossing behavior via the internet, a medium that could be broadly disseminated at low cost. Ten 7- and 8-year-old children participated. They engaged in an internet-based virtual pedestrian environment and completed a brief assessment survey. Researchers rated children's behavior while engaged in the game. Both self-report and researcher observations indicated the internet-based system was readily used by the children without adult support. The youth understood how to engage in the system and used it independently and attentively. The program also was feasible. It provided multiple measures of pedestrian safety that could be used for research or training purposes. Finally, the program was rated by children as engaging and educational. Researcher ratings suggested children used the program with minimal fidgeting or boredom. The pilot test suggests an internet-based virtual pedestrian environment offers a usable, feasible, engaging, and educational environment for child pedestrian safety training. If future research finds children learn the cognitive and perceptual skills needed to cross streets safely within it, internet-based training may provide a low-cost medium to broadly disseminate child pedestrian safety training. The concept may be generalized to other domains of health-related functioning such as teen driving safety, adolescent sexual risk-taking, and adolescent substance use. PMID:24678263

  9. Boundary Layer

    NASA Technical Reports Server (NTRS)

    Loitsianskii. L. G.

    1956-01-01

    The fundamental, practically the most important branch of the modern mechanics of a viscous fluid or a gas, is that branch which concerns itself with the study of the boundary layer. The presence of a boundary layer accounts for the origin of the resistance and lift force, the breakdown of the smooth flow about bodies, and other phenomena that are associated with the motion of a body in a real fluid. The concept of boundary layer was clearly formulated by the founder of aerodynamics, N. E. Joukowsky, in his well-known work "On the Form of Ships" published as early as 1890. In his book "Theoretical Foundations of Air Navigation," Joukowsky gave an account of the most important properties of the boundary layer and pointed out the part played by it in the production of the resistance of bodies to motion. The fundamental differential equations of the motion of a fluid in a laminar boundary layer were given by Prandtl in 1904; the first solutions of these equations date from 1907 to 1910. As regards the turbulent boundary layer, there does not exist even to this day any rigorous formulation of this problem because there is no closed system of equations for the turbulent motion of a fluid. Soviet scientists have done much toward developing a general theory of the boundary layer, and in that branch of the theory which is of greatest practical importance at the present time, namely the study of the boundary layer at large velocities of the body in a compressed gas, the efforts of the scientists of our country have borne fruit in the creation of a new theory which leaves far behind all that has been done previously in this direction. We shall herein enumerate the most important results by Soviet scientists in the development of the theory of the boundary layer.

  10. Evaluation of the safety benefits of legacy safe routes to school programs

    DOT National Transportation Integrated Search

    2008-08-01

    This study first examined the feasibility of conducting a crash-based assessment of the safety effects of legacy Safe Routes to School : (SRTS) programs. These were SRTS programs operating before the passage of the Safe, Accountable, Flexible, Effici...

  11. Environmentally safe fluids for hydraulics used in civil engineering

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

    Wirzberger, E.; Rexroth, M.

    1995-12-31

    The majority of hydraulic units used in civil engineering are operated with pressure fluids based on mineral oil. Most civil engineering projects are installed near or immediately next to bodies of water, therefore, any leakage signifies danger for the environment. We try to avert this danger with increasingly safe hydraulic drives. However, growing environmental awareness and stricter laws are demanding more and more environmentally safe hydraulic fluids. Today, the manufacturers of fluids and hydraulic drives have to accept this challenge. What exactly is an environmentally safe hydraulic fluid? The major objectives are: (1) they have to be biodegradable, (2) nomore » fish toxicity, (3) no water pollution, and (4) food compatibility.« less

  12. Enhancement of Perfluoropolyether Boundary Lubrication Performance

    NASA Technical Reports Server (NTRS)

    Jones, W. R., Jr.; Ajayi, O. O.; Wedeven, L. D.

    1996-01-01

    A ball bearing simulator operating under starved conditions was used to perform screening tests to evaluate the boundary lubrication performance of a branched perfluoropolyether (PFPE), K-143 AB. Several approaches to enhance boundary lubrication were studied. These included: (1) soluble boundary additives, (2) bearing surface modifications, (3) 'run-in' surface films, and (4) ceramic bearing components. In addition, results were compared with two non-perfluorinated liquid lubricant formulations. Based on these tests, the following tentative conclusions can be made: (1) Substantial improvements in boundary lubrication performance were observed with a beta-diketone boundary additive and a tricresyl phosphate (TCP) liquid surface pretreatment, (2) the use of rough Si3N4 balls (R(sub a) = 40 micro-inch) also provided increases in test duration, but with concomitant abrasive wear, (3) moderate improvements were seen with two boundary additives (a phosphine and a phosphatriazine) and a neat (100%) fluid (a carboxylic acid terminated PFPE); and small improvements with surface pretreatments with synthetic hydrocarbons, a polytetrafluoroethylene (PTFE) coating, and TiC coated 440 C and smooth Si3N4 balls (R(sub a) = 1 micro-inch), and (4) two non-PFPE lubricant formulations (a polyalphaolefin (PAO) and synthetic hydrocarbon) yielded substantial improvements.

  13. Impact of Community-Based Approach as Policy Tool: World Health Organization-Designated Safe Communities of Korea and Health Action Zones of the United Kingdom.

    PubMed

    Kang, Changhyun; Shin, Jihyung; Matthews, Bob

    2016-02-01

    The aim of this study is to ascertain and identify the effectiveness of area-based initiatives as a policy tool mediated by societal and individual factors in the five World Health Organization (WHO)-designated Safe Communities of Korea and the Health Action Zones of the United Kingdom (UK). The Korean National Hospital discharge in-depth injury survey from the Korea Centers for Disease Control and Prevention and causes of death statistics by the Statistics Korea were used for all analyses. The trend and changes in injury rate and mortality by external causes were compared among the five WHO-designated Safe Communities in Korea. The injury incident rates decreased at a greater level in the Safe Communities compared with the national average. Similar results were shown for the changes in unintentional injury incident rates. In comparison of changes in mortality rate by external causes between 2005 and 2011, the rate increase in Safe Communities was higher than the national average except for Jeju, where the mortality rate by external causes decreased. When the Healthy Action Zones of the UK and the WHO Safe Communities of Korea were examined, the outcomes were interpreted differently among the compared index, regions, and time periods. Therefore, qualitative outcomes, such as bringing the residents' attention to the safety of the communities and promoting participation and coordination of stakeholders, should also be considered as important impacts of the community-based initiatives.

  14. Impact of Community-Based Approach as Policy Tool: World Health Organization-Designated Safe Communities of Korea and Health Action Zones of the United Kingdom

    PubMed Central

    Kang, Changhyun; Shin, Jihyung; Matthews, Bob

    2015-01-01

    Objectives The aim of this study is to ascertain and identify the effectiveness of area-based initiatives as a policy tool mediated by societal and individual factors in the five World Health Organization (WHO)-designated Safe Communities of Korea and the Health Action Zones of the United Kingdom (UK). Methods The Korean National Hospital discharge in-depth injury survey from the Korea Centers for Disease Control and Prevention and causes of death statistics by the Statistics Korea were used for all analyses. The trend and changes in injury rate and mortality by external causes were compared among the five WHO-designated Safe Communities in Korea. Results The injury incident rates decreased at a greater level in the Safe Communities compared with the national average. Similar results were shown for the changes in unintentional injury incident rates. In comparison of changes in mortality rate by external causes between 2005 and 2011, the rate increase in Safe Communities was higher than the national average except for Jeju, where the mortality rate by external causes decreased. Conclusion When the Healthy Action Zones of the UK and the WHO Safe Communities of Korea were examined, the outcomes were interpreted differently among the compared index, regions, and time periods. Therefore, qualitative outcomes, such as bringing the residents' attention to the safety of the communities and promoting participation and coordination of stakeholders, should also be considered as important impacts of the community-based initiatives. PMID:26981341

  15. Grain Boundary Character Distributions In Isostructural Materials

    NASA Astrophysics Data System (ADS)

    Ratanaphan, Sutatch

    3, Sigma9, and Sigma27). Because the enhancement of twin related boundaries due to the prevalence Sigma3 boundaries results in a decrease in the grain boundary populations for the other boundary types, this inverse correlation is influenced by the crystallographic constraints at triple junctions. In other words, having an anisotropic misorientation distribution with strong maxima for certain boundaries biases the inverse correlation between grain boundary population and energy for other boundaries and causes different slopes at each misorientation. Interestingly, the inverse correlation at each misorientation is consistent with the Boltzmann distribution. Based on our results, it is possible to predict the GBCDs and GBEDs in isostructural polycrystalline materials by using a single GBCD and GBED. This principle is demonstrated by predicting the GBCD and GBED of Actinium (Ac). To investigate the GBED in the isostructural BCC metals, the energies of 408 grain boundaries in Fe and Mo were computed using atomistic simulations based on the embedded-atom method (EAM) potential. We found that the calculated boundary energies in Fe and Mo were strongly correlated and scaled with the ratio of the cohesive energy divided by the square of the lattice constant (Ecoh/a02). We would expect that the GBCD of Fe and Mo might be correlated in a similar manner to that of FCC metals. To test this hypothesis, we compared the GBCDs of Fe and Mo. We found that the GBCDs of Fe and Mo are moderately and strongly correlated when all boundary types and only Sigma3 boundaries were considered, respectively. In this thesis, the results demonstrated that the GBCDs of isostructural materials are correlated with one another and the magnitudes of correlation coefficients varied. Reduced correlations were observed when there were differences in the microstructure and crystallographic texture. The inverse relationship between grain boundary population and energy is more strongly correlated at each

  16. Safe and Durable High-Temperature Lithium-Sulfur Batteries via Molecular Layer Deposited Coating.

    PubMed

    Li, Xia; Lushington, Andrew; Sun, Qian; Xiao, Wei; Liu, Jian; Wang, Biqiong; Ye, Yifan; Nie, Kaiqi; Hu, Yongfeng; Xiao, Qunfeng; Li, Ruying; Guo, Jinghua; Sham, Tsun-Kong; Sun, Xueliang

    2016-06-08

    Lithium-sulfur (Li-S) battery is a promising high energy storage candidate in electric vehicles. However, the commonly employed ether based electrolyte does not enable to realize safe high-temperature Li-S batteries due to the low boiling and flash temperatures. Traditional carbonate based electrolyte obtains safe physical properties at high temperature but does not complete reversible electrochemical reaction for most Li-S batteries. Here we realize safe high temperature Li-S batteries on universal carbon-sulfur electrodes by molecular layer deposited (MLD) alucone coating. Sulfur cathodes with MLD coating complete the reversible electrochemical process in carbonate electrolyte and exhibit a safe and ultrastable cycle life at high temperature, which promise practicable Li-S batteries for electric vehicles and other large-scale energy storage systems.

  17. Buying & Using Medicine Safely

    MedlinePlus

    ... Generic Drugs - Patient Education Resources Patient and Prescriber materials: Videos, PSAs, factsheets and more. Spotlight Drugs@FDA Index to Drug-Specific Information Protecting Yourself Safe Disposal of Medicines Generic Medicines – safe, effective and ...

  18. The use of MACSYMA for solving elliptic boundary value problems

    NASA Technical Reports Server (NTRS)

    Thejll, Peter; Gilbert, Robert P.

    1990-01-01

    A boundary method is presented for the solution of elliptic boundary value problems. An approach based on the use of complete systems of solutions is emphasized. The discussion is limited to the Dirichlet problem, even though the present method can possibly be adapted to treat other boundary value problems.

  19. Reactive, Safe Navigation for Lunar and Planetary Robots

    NASA Technical Reports Server (NTRS)

    Utz, Hans; Ruland, Thomas

    2008-01-01

    When humans return to the moon, Astronauts will be accompanied by robotic helpers. Enabling robots to safely operate near astronauts on the lunar surface has the potential to significantly improve the efficiency of crew surface operations. Safely operating robots in close proximity to astronauts on the lunar surface requires reactive obstacle avoidance capabilities not available on existing planetary robots. In this paper we present work on safe, reactive navigation using a stereo based high-speed terrain analysis and obstacle avoidance system. Advances in the design of the algorithms allow it to run terrain analysis and obstacle avoidance algorithms at full frame rate (30Hz) on off the shelf hardware. The results of this analysis are fed into a fast, reactive path selection module, enforcing the safety of the chosen actions. The key components of the system are discussed and test results are presented.

  20. A visual detection of protein content based on titration of moving reaction boundary electrophoresis.

    PubMed

    Wang, Hou-Yu; Guo, Cheng-Ye; Guo, Chen-Gang; Fan, Liu-Yin; Zhang, Lei; Cao, Cheng-Xi

    2013-04-24

    A visual electrophoretic titration method was firstly developed from the concept of moving reaction boundary (MRB) for protein content analysis. In the developed method, when the voltage was applied, the hydroxide ions in the cathodic vessel moved towards the anode, and neutralized the carboxyl groups of protein immobilized via highly cross-linked polyacrylamide gel (PAG), generating a MRB between the alkali and the immobilized protein. The boundary moving velocity (V(MRB)) was as a function of protein content, and an acid-base indicator was used to denote the boundary displacement. As a proof of concept, standard model proteins and biological samples were chosen for the experiments to study the feasibility of the developed method. The experiments revealed that good linear calibration functions between V(MRB) and protein content (correlation coefficients R>0.98). The experiments further demonstrated the following merits of developed method: (1) weak influence of non-protein nitrogen additives (e.g., melamine) adulterated in protein samples, (2) good agreement with the classic Kjeldahl method (R=0.9945), (3) fast measuring speed in total protein analysis of large samples from the same source, and (4) low limit of detection (0.02-0.15 mg mL(-1) for protein content), good precision (R.S.D. of intra-day less than 1.7% and inter-day less than 2.7%), and high recoveries (105-107%). Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

  1. [Delineation of urban development boundary based on the combination of rigidity and elasti-city: A case of Yiwu City in Zhejiang Province, China.

    PubMed

    Qiu, Si Qi; Yue, Wen Ze

    2018-05-01

    Under the background of rapid urbanization, we took the contradiction between the rapid urbanization and resource environment protection as the starting point, conducted some theoretical research on urban growth boundary. Based on the definition of urban development boundary, we took Yiwu City, Zhejiang Province as a typical instance. Firstly, this study delimited the ecological boundary as ecological basic constraint area, using the methods of ecological red line discrimination and ecological sensitivity evaluation. Furthermore, the MCE-CA model was used in simulating the city size in 2020, making some adjustments to the moderate and low ecological-sensitive areas in the eco-sensitivity assessing, and delimiting the size of urban growth boundary and elastic control zones. The results showed that the ecological constraint area with a total area of385.2 km 2 and outside of the ecological boundary was the security line of urban development and construction. The urban growth boundary with a total area of 163.3 km 2 was not only the spatial boundary that could be constructed now, but also could meet the future development and construction. The district between the ecological boundary and urban growth boundary was an elastic control zone, in which urban development activities were allowed, but the size of construction could not exceed 8.5% of the total urban development boundary area. Our results delimited the urban development boundary under the rigidity and elasticity, which could guide the urban space development and provide a theoretical reference for China.

  2. Combining the boundary shift integral and tensor-based morphometry for brain atrophy estimation

    NASA Astrophysics Data System (ADS)

    Michalkiewicz, Mateusz; Pai, Akshay; Leung, Kelvin K.; Sommer, Stefan; Darkner, Sune; Sørensen, Lauge; Sporring, Jon; Nielsen, Mads

    2016-03-01

    Brain atrophy from structural magnetic resonance images (MRIs) is widely used as an imaging surrogate marker for Alzheimers disease. Their utility has been limited due to the large degree of variance and subsequently high sample size estimates. The only consistent and reasonably powerful atrophy estimation methods has been the boundary shift integral (BSI). In this paper, we first propose a tensor-based morphometry (TBM) method to measure voxel-wise atrophy that we combine with BSI. The combined model decreases the sample size estimates significantly when compared to BSI and TBM alone.

  3. Spatial distribution of child pedestrian injuries along census tract boundaries: Implications for identifying area-based correlates.

    PubMed

    Curtis, Jacqueline W

    2017-01-01

    Census tracts are often used to investigate area-based correlates of a variety of health outcomes. This approach has been shown to be valuable in understanding the ways that health is shaped by place and to design appropriate interventions that account for community-level processes. Following this line of inquiry, it is common in the study of pedestrian injuries to aggregate the point level locations of these injuries to the census tracts in which they occur. Such aggregation enables investigation of the relationships between a range of socioeconomic variables and areas of notably high or low incidence. This study reports on the spatial distribution of child pedestrian injuries in a mid-sized U.S. city over a three-year period. Utilizing a combination of geospatial approaches, Near Analysis, Kernel Density Estimation, and Local Moran's I, enables identification, visualization, and quantification of close proximity between incidents and tract boundaries. Specifically, results reveal that nearly half of the 100 incidents occur within roads that are also census tract boundaries. Results also uncover incidents that occur on tract boundaries, not merely near them. This geographic pattern raises the question of the utility of associating area-based census data from any one tract to the injuries occurring in these border zones. Furthermore, using a standard spatial join technique in a Geographic Information System (GIS), these points located on the border are counted as falling into census tracts on both sides of the boundary, which introduces uncertainty in any subsequent analysis. Therefore, two additional approaches of aggregating points to polygons were tested in this study. Results differ with each approach, but without any alert of such differences to the GIS user. This finding raises a fundamental concern about techniques through which points are aggregated to polygons in any study using point level incidents and their surrounding census tract socioeconomic data to

  4. Comparison of artificial absorbing boundaries for acoustic wave equation modelling

    NASA Astrophysics Data System (ADS)

    Gao, Yingjie; Song, Hanjie; Zhang, Jinhai; Yao, Zhenxing

    2017-12-01

    Absorbing boundary conditions are necessary in numerical simulation for reducing the artificial reflections from model boundaries. In this paper, we overview the most important and typical absorbing boundary conditions developed throughout history. We first derive the wave equations of similar methods in unified forms; then, we compare their absorbing performance via theoretical analyses and numerical experiments. The Higdon boundary condition is shown to be the best one among the three main absorbing boundary conditions that are based on a one-way wave equation. The Clayton and Engquist boundary is a special case of the Higdon boundary but has difficulty in dealing with the corner points in implementaion. The Reynolds boundary does not have this problem but its absorbing performance is the poorest among these three methods. The sponge boundary has difficulties in determining the optimal parameters in advance and too many layers are required to achieve a good enough absorbing performance. The hybrid absorbing boundary condition (hybrid ABC) has a better absorbing performance than the Higdon boundary does; however, it is still less efficient for absorbing nearly grazing waves since it is based on the one-way wave equation. In contrast, the perfectly matched layer (PML) can perform much better using a few layers. For example, the 10-layer PML would perform well for absorbing most reflected waves except the nearly grazing incident waves. The 20-layer PML is suggested for most practical applications. For nearly grazing incident waves, convolutional PML shows superiority over the PML when the source is close to the boundary for large-scale models. The Higdon boundary and hybrid ABC are preferred when the computational cost is high and high-level absorbing performance is not required, such as migration and migration velocity analyses, since they are not as sensitive to the amplitude errors as the full waveform inversion.

  5. Redefinition of the Meramecian/Chesterian boundary (Mississippian)

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

    Maples, C.G.; Waters, J.A.

    1987-07-01

    The Meramecian/Chesterian (Mississippi) boundary in the type area is currently defined as the highest occurrence of the crinoid Platycrinites penicillus and the lowest occurrence of the crinoid genera Agassizocrinus and Talarocrinus. Because these taxa have not been reported outside eastern North America, attempts have been made to use conodonts and Foraminifera to extend the Meramecian/Chesterian boundary outside the type area. Unfortunately, changes in conodont and foraminiferal assemblages do not coincide with the currently defined Meramecian/Chesterian boundary, and use of these fossil groups does not allow exact placement of the boundary outside of eastern North America. The authors suggest that themore » Meramecian/Chesterian boundary be redefined as the boundary between Foraminiferal Zones 15 and 16i of the Mamet scheme, irrespective of the occurrence of Platycrinites penicillus. This change in definition places the Ste. Genevieve Limestone (Genevievian Stage) in the lowermost part of the Chesterian Series, with which it is biotically and sedimentologically more allied than with the underlying St. Louis Limestone. This change provides a sound biostratigraphic base for correlating the Meramecian/Chesterian boundary outside of the type area. Foraminifera, conodonts, brachiopods, and corals all show significant changes at or slightly below the St. Louis/Ste. Genevieve contact rather than at the Genevievian/Chesterian contact. 52 references.« less

  6. Defining the safe current limit for opening ID photon shutter

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

    Seletskiy, S.

    The NSLS-II storage ring is protected from possible damage from insertion devices (IDs) synchrotron radiation by a dedicated active interlock system (AIS). It monitors electron beam position and angle and triggers beam drop if beam orbit exceeds the boundaries of pre-calculated active interlock envelope (AIE). The beamlines (BL) and beamline frontends (FE) are designed under assumption that the electron beam is interlocked within the AIE. For historic reasons the AIS engages the ID active interlock (AI-ID) at any non-zero beam current whenever the ID photon shutter (IDPS) is getting opened. Such arrangement creates major inconveniences for BLs commissioning. Apparently theremore » is some IDPS safe current limit (SCL) under which the IDPS can be opened without interlocking the e-beam. The goal of this paper is to find such limit.« less

  7. Safe motherhood partners -- the International Children's Centre.

    PubMed

    1994-01-01

    The International Children's Centre (ICC) works worldwide to improve child health in the least developed countries. In its training and research projects the agency contributes to the Safe Motherhood Initiative to improve the health of mothers and infants. ICC is based in Paris, it was established in 1949, and the agency has cooperated with governments, nongovernmental organizations and international bodies like the World Health Organization (WHO) in child care. ICC's activities reflect concern for the health of women before and during pregnancy and the rest of their lives. The center's work comprises training, research, local projects, and information and documentation. Following the 1987 Nairobi conference on safe motherhood, ICC organized a seminar in Paris on maternal mortality in Sub-Saharan francophone Africa, which led to participation in the Safe Motherhood Initiative with a variety of training and research programs. ICC training is integrated, community-based, and multidisciplinary. Anthropology, psychology, economics and management have played a role in ICC training courses. The center runs an international course on maternal and child health from January to April each year and also organizes distance training courses on problem solving in health care. ICC training programs have taken place in Laos, Senegal, and Vietnam to strengthen the work of maternal and child health training centers there. A 4-week course on economic evaluation of health programs is held in Paris each July. In 1989 and 1990, ICC organized in collaboration with WHO safe motherhood workshops on research methodology in Benin and in Burkina Faso with participants from 6 francophone African countries. One research project in Benin is on risk factors for maternal and perinatal mortality and morbidity, and the other in Cameroon on improving surveillance of pregnancy, delivery, and the postnatal period. ICC focuses on long-term planning and action for the benefit of mothers and children.

  8. Global-to-local, shape-based, real and virtual landmarks for shape modeling by recursive boundary subdivision

    NASA Astrophysics Data System (ADS)

    Rueda, Sylvia; Udupa, Jayaram K.

    2011-03-01

    Landmark based statistical object modeling techniques, such as Active Shape Model (ASM), have proven useful in medical image analysis. Identification of the same homologous set of points in a training set of object shapes is the most crucial step in ASM, which has encountered challenges such as (C1) defining and characterizing landmarks; (C2) ensuring homology; (C3) generalizing to n > 2 dimensions; (C4) achieving practical computations. In this paper, we propose a novel global-to-local strategy that attempts to address C3 and C4 directly and works in Rn. The 2D version starts from two initial corresponding points determined in all training shapes via a method α, and subsequently by subdividing the shapes into connected boundary segments by a line determined by these points. A shape analysis method β is applied on each segment to determine a landmark on the segment. This point introduces more pairs of points, the lines defined by which are used to further subdivide the boundary segments. This recursive boundary subdivision (RBS) process continues simultaneously on all training shapes, maintaining synchrony of the level of recursion, and thereby keeping correspondence among generated points automatically by the correspondence of the homologous shape segments in all training shapes. The process terminates when no subdividing lines are left to be considered that indicate (as per method β) that a point can be selected on the associated segment. Examples of α and β are presented based on (a) distance; (b) Principal Component Analysis (PCA); and (c) the novel concept of virtual landmarks.

  9. Cultivating the Art of Safe Space

    ERIC Educational Resources Information Center

    Hunter, Mary Ann

    2008-01-01

    Performance-making and peace-building are processes predicated on the production of safe space. But what is "safe space"? In performance-making, what is it that makes space safe without losing the creative potential of tension? What role is there for risk? And, once achieved, how does safe space become meaningful beyond its immediate…

  10. Safe Affordable Fission Engine-(SAFE-) 100a Heat Exchanger Thermal and Structural Analysis

    NASA Technical Reports Server (NTRS)

    Steeve, B. E.

    2005-01-01

    A potential fission power system for in-space missions is a heat pipe-cooled reactor coupled to a Brayton cycle. In this system, a heat exchanger (HX) transfers the heat of the reactor core to the Brayton gas. The Safe Affordable Fission Engine- (SAFE-) 100a is a test program designed to thermally and hydraulically simulate a 95 Btu/s prototypic heat pipe-cooled reactor using electrical resistance heaters on the ground. This Technical Memorandum documents the thermal and structural assessment of the HX used in the SAFE-100a program.

  11. Stability of hyperbolic-parabolic mixed type equations with partial boundary condition

    NASA Astrophysics Data System (ADS)

    Zhan, Huashui; Feng, Zhaosheng

    2018-06-01

    In this paper, we are concerned with the hyperbolic-parabolic mixed type equations with the non-homogeneous boundary condition. If it is degenerate on the boundary, the part of the boundary whose boundary value should be imposed, is determined by the entropy condition from the convection term. If there is no convection term in the equation, we show that the stability of solutions can be proved without any boundary condition. If the equation is completely degenerate, we show that the stability of solutions can be established just based on the partial boundary condition.

  12. Digital image registration method based upon binary boundary maps

    NASA Technical Reports Server (NTRS)

    Jayroe, R. R., Jr.; Andrus, J. F.; Campbell, C. W.

    1974-01-01

    A relatively fast method is presented for matching or registering the digital data of imagery from the same ground scene acquired at different times, or from different multispectral images, sensors, or both. It is assumed that the digital images can be registed by using translations and rotations only, that the images are of the same scale, and that little or no distortion exists between images. It is further assumed that by working with several local areas of the image, the rotational effects in the local areas can be neglected. Thus, by treating the misalignments of local areas as translations, it is possible to determine rotational and translational misalignments for a larger portion of the image containing the local areas. This procedure of determining the misalignment and then registering the data according to the misalignment can be repeated until the desired degree of registration is achieved. The method to be presented is based upon the use of binary boundary maps produced from the raw digital imagery rather than the raw digital data.

  13. The Role of Grain Boundary Energy on Grain Boundary Complexion Transitions

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

    Bojarski, Stephanie A.; Rohrer, Gregory S.

    Grain boundary complexions are distinct equilibrium structures and compositions of a grain boundary and complexion transformations are transition from a metastable to an equilibrium complexion at a specific thermodynamic and geometric conditions. Previous work indicates that, in the case of doped alumina, a complexion transition that increased the mobility of transformed boundaries and resulted in abnormal grain growth also caused a decrease in the mean relative grain boundary energy as well as an increase in the anisotropy of the grain boundary character distribution (GBCD). The current work will investigate the hypothesis that the rates of complexion transitions that result inmore » abnormal grain growth (AGG) depend on grain boundary character and energy. Furthermore, the current work expands upon this understanding and tests the hypothesis that it is possible to control when and where a complexion transition occurs by controlling the local grain boundary energy distribution.« less

  14. Behavioral Determinants of Switching to Arsenic-Safe Water Wells.

    PubMed

    George, Christine Marie; Inauen, Jennifer; Perin, Jamie; Tighe, Jennifer; Hasan, Khaled; Zheng, Yan

    2017-02-01

    More than 100 million people globally are estimated to be exposed to arsenic in drinking water that exceeds the World Health Organization guideline of 10 µg/L. In an effort to develop and test a low-cost sustainable approach for water arsenic testing in Bangladesh, we conducted a randomized controlled trial which found arsenic educational interventions when combined with fee-based water arsenic testing programs led to nearly all households buying an arsenic test for their drinking water sources (93%) compared with only 53% when fee-based arsenic testing alone was offered. The aim of the present study was to build on the findings of this trial by investigating prospectively the psychological factors that were most strongly associated with switching to arsenic-safe wells in response to these interventions. Our theoretical framework was the RANAS (risk, attitude, norm, ability, and self-regulation) model of behavior change. In the multivariate logistic regression model of 285 baseline unsafe well users, switching to an arsenic-safe water source was significantly associated with increased instrumental attitude (odds ratio [OR] = 9.12; 95% confidence interval [CI] = [1.85, 45.00]), descriptive norm (OR = 34.02; 95% CI = [6.11, 189.45]), coping planning (OR = 11.59; 95% CI = [3.82, 35.19]), and commitment (OR = 10.78; 95% CI = [2.33, 49.99]). In addition, each additional minute from the nearest arsenic-safe drinking water source reduced the odds of switching to an arsenic-safe well by more than 10% (OR = 0.89; 95% CI = [0.87, 0.92]). Future arsenic mitigation programs should target these behavioral determinants of switching to arsenic-safe water sources.

  15. Equilibrium composition of interphase boundaries

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

    Wynblatt, P.

    1990-01-01

    Two modeling approaches have been used to investigate segregation effects at interphase boundaries. The first approach is based on the nearest neighbor bond model, used in conjunction with the regular solution approximation, and is an extension of an earlier framework developed to address segregation phenomena at free surfaces. In order to model a semicoherent interphase boundary, we have employed a second modeling approach, based on Monte Carol simulation, in conjunction with the embedded atom method (EAM). The EAM is a powerful new method for describing interatomic interactions in metallic systems. It includes certain many-body interactions that depend on the localmore » environment of an atom. The Monte Carol approach has been applied to semicoherent interphase boundaries in Cu-Ag-Au alloys dilute in Au. These alloys consist of coexisting Cu-rich and Ag-rich phases, which differ in lattice constant by about 12%, such that good matching across in interface occurs when nine structural units of the Cu-rich phase are opposed to eight structural units of the Ag-rich phase. Thus far, interfaces with two different orientations have been studied: {l brace}001{r brace}-Cu//{l brace}001{r brace}-Ag, {l angle}110{r angle}-Cu//{l angle}110{r angle}-Ag; and {l brace}111{r brace}-Cu//{l brace}111{r brace}-Ag, {l angle}110{r angle}-Cu//{l angle}110{r angle}-Ag. These two interfaces will be referred to as the (001) and (111) interphase boundaries, for short. 18 refs.« less

  16. A Wave-Optics Approach to Paraxial Geometrical Laws Based on Continuity at Boundaries

    ERIC Educational Resources Information Center

    Linares, J.; Nistal, M. C.

    2011-01-01

    We present a derivation of the paraxial geometrical laws starting from a wave-optics approach, in particular by using simple continuity conditions of paraxial spherical waves at boundaries (discontinuities) between optical media. Paraxial geometrical imaging and magnification laws, under refraction and reflection at boundaries, are derived for…

  17. Ground-water-level monitoring, basin boundaries, and potentiometric surfaces of the aquifer system at Edwards Air Force Base, California, 1992

    USGS Publications Warehouse

    Rewis, D.L.

    1995-01-01

    A ground-water-level monitoring program was implemented at Edwards Air Force Base, California, from January through December 1992 to monitor spatial and temporal changes in poten-tiometric surfaces that largely are affected by ground-water pumping. Potentiometric-surface maps are needed to determine the correlation between declining ground- water levels and the distribution of land subsidence. The monitoring program focused on areas of the base where pumping has occurred, especially near Rogers Lake, and involved three phases of data collection: (1) well canvassing and selection, (2) geodetic surveys, and (3) monthly ground-water-level measurements. Construction and historical water- level data were compiled for 118 wells and pi-ezometers on or near the base, and monthly ground-water-level measurements were made in 82 wells and piezometers on the base. The compiled water-level data were used in conjunction with previously collected geologic data to identify three types of no-flow boundaries in the aquifer system: structural boundaries, a principal-aquifer boundary, and ground-water divides. Heads were computed from ground-water-level measurements and land-surface altitudes and then were used to map seasonal potentiometric surfaces for the principal and deep aquifers underlying the base. Pumping has created a regional depression in the potentiometric surface of the deep aquifer in the South Track, South Base, and Branch Park well-field area. A 15-foot decline in the potentiometric surface from April to September 1992 and 20- to 30-foot drawdowns in the three production wells in the South Track well field caused locally unconfined conditions in the deep aquifer.

  18. Breastfeeding FAQs: Safely Storing Breast Milk

    MedlinePlus

    ... Staying Safe Videos for Educators Search English Español Breastfeeding FAQs: Safely Storing Breast Milk KidsHealth / For Parents / Breastfeeding FAQs: Safely Storing Breast Milk What's in this ...

  19. Novel choline-based ionic liquids as safe electrolytes for high-voltage lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Yong, Tianqiao; Zhang, Lingzhi; Wang, Jinglun; Mai, Yongjin; Yan, Xiaodan; Zhao, Xinyue

    2016-10-01

    Three choline-based ionic liquids functionalized with trimethylsilyl, allyl, and cynoethyl groups are synthesized in an inexpensive route as safe electrolytes for high-voltage lithium-ion batteries. The thermal stabilities, viscosities, conductivities, and electrochemical windows of these ILs are reported. Hybrid electrolytes were formulated by doping with 0.6 M LiPF6/0.4 M lithium oxalydifluoroborate (LiODFB) as salts and dimethyl carbonate (DMC) as co-solvent. By using 0.6 M LiPF6/0.4 M LiODFB trimethylsilylated choline-based IL (SN1IL-TFSI)/DMC as electrolyte, LiCoO2/graphite full cell showed excellent cycling performance with a capacity of 152 mAh g-1 and 99% capacity retention over 90 cycles at a cut-off voltage of 4.4 V. The propagation rate of SN1IL-TFSI)/DMC electrolyte is only one quarter of the commercial electrolyte (1 M LiPF6 EC/DEC/DMC, v/v/v = 1/1/1), suggesting a better safety feature.

  20. Self-Reconfiguration Planning of Robot Embodiment for Inherent Safe Performance

    NASA Astrophysics Data System (ADS)

    Uchida, Masafumi; Nozawa, Akio; Asano, Hirotoshi; Onogaki, Hitoshi; Mizuno, Tota; Park, Young-Il; Ide, Hideto; Yokoyama, Shuichi

    In the situation in which a robot and a human work together by collaborating with each other, a robot and a human share one working environment, and each interferes in each other. In other ward, it is impossible to avoid the physical contact and the interaction of force between a robot and a human. The boundary of each complex dynamic occupation area changes in the connection movement which is the component of collaborative works at this time. The main restraint condition which relates to the robustness of that connection movement is each physical charactristics, that is, the embodiment. A robot body is variability though the embodiment of a human is almost fixed. Therefore, the safe and the robust connection movement is brought when a robot has the robot body which is well suitable for the embodiment of a human. A purpose for this research is that the colaboration works between the self-reconfiguration robot and a human is realized. To achieve this purpose, a self-reconfiguration algorithm based on some indexes to evaluate a robot body in the macroscopic point of view was examined on a modular robot system of the 2-D lattice structure. In this paper, it investigated effect specially that the object of learning of each individual was limited to the cooperative behavior between the adjoining modules toward the macroscopic evaluation index.

  1. The Network of Excellence 'Knowledge-based Multicomponent Materials for Durable and Safe Performance'

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

    Moreno, Arnaldo

    The Network of Excellence 'Knowledge-based Multicomponent Materials for Durable and Safe Performance' (KMM-NoE) consists of 36 institutional partners from 10 countries representing leading European research institutes and university departments (25), small and medium enterprises, SMEs (5) and large industry (7) in the field of knowledge-based multicomponent materials (KMM), more specifically in intermetallics, metal-ceramic composites, functionally graded materials and thin layers. The main goal of the KMM-NoE (currently funded by the European Commission) is to mobilise and concentrate the fragmented scientific potential in the KMM field to create a durable and efficient organism capable of developing leading-edge research while spreading themore » accumulated knowledge outside the Network and enhancing the technological skills of the related industries. The long-term strategic goal of the KMM-NoE is to establish a self-supporting pan-European institution in the field of knowledge-based multicomponent materials--KMM Virtual Institute (KMM-VIN). It will combine industry oriented research with educational and training activities. The KMM Virtual Institute will be founded on three main pillars: KMM European Competence Centre, KMM Integrated Post-Graduate School, KMM Mobility Programme. The KMM-NoE is coordinated by the Institute of Fundamental Technological Research (IPPT) of the Polish Academy of Sciences, Warsaw, Poland.« less

  2. Ecological quality boundary-setting procedures: the Gulf of Riga case study.

    PubMed

    Aigars, Juris; Müller-Karulis, Bärbel; Martin, Georg; Jermakovs, Vadims

    2008-03-01

    Two approaches for setting ecological class boundaries, response curves and a simplified mathematical boundary-setting protocol, were tested for coastal, transitional and open waters in the Gulf of Riga, Baltic Sea. The simplified mathematical boundary-setting protocol defines acceptable ecological status based on expert judgment by a uniform relative deviation from reference conditions. In contrast, response curves derive class boundary definitions from observed changes in biological quality elements along environmental pressure gradients for class boundary definitions. Identification of relevant environmental pressures for the construction of response curves was based on a conceptual model of eutrophication in the Gulf of Riga. Response curves were successfully established for summer chlorophyll a and transparency, as well as for macrozoobenthos abundance in the Central Gulf, macrozoobenthos biotic coefficient in the Southern Gulf, and maximum depth of phytobenthos in the Northern Gulf. In the Gulf of Riga response curves almost always permitted a larger deviation from reference conditions than the 50% deviation applied for the simplified mathematical boundary-setting protocol. The case study clearly demonstrated that class boundary definitions should take into account the sensitivity of the target water body. Also, the class boundaries for different ecological quality elements were internally more consistent than those derived by the simplified mathematical boundary-setting protocol.

  3. The role of boundary variability in polycrystalline grain-boundary diffusion

    NASA Astrophysics Data System (ADS)

    Moghadam, M. M.; Rickman, J. M.; Harmer, M. P.; Chan, H. M.

    2015-01-01

    We investigate the impact of grain-boundary variability on mass transport in a polycrystal. More specifically, we perform both numerical and analytical studies of steady-state diffusion in prototypical microstructures in which there is either a discrete spectrum of grain-boundary activation energies or else a complex distribution of grain-boundary character, and hence a continuous spectrum of boundary activation energies. An effective diffusivity is calculated for these structures using simplified multi-state models and, for the case of a continuous spectrum, employing experimentally obtained grain-boundary energy data. We identify different diffusive regimes for these cases and quantify deviations from Arrhenius behavior using effective medium theory. Finally, we examine the diffusion kinetics of a simplified model of an interfacial layering (i.e., complexion) transition.

  4. Asymptotic boundary conditions for dissipative waves: General theory

    NASA Technical Reports Server (NTRS)

    Hagstrom, Thomas

    1990-01-01

    An outstanding issue in the computational analysis of time dependent problems is the imposition of appropriate radiation boundary conditions at artificial boundaries. Accurate conditions are developed which are based on the asymptotic analysis of wave propagation over long ranges. Employing the method of steepest descents, dominant wave groups are identified and simple approximations to the dispersion relation are considered in order to derive local boundary operators. The existence of a small number of dominant wave groups may be expected for systems with dissipation. Estimates of the error as a function of domain size are derived under general hypotheses, leading to convergence results. Some practical aspects of the numerical construction of the asymptotic boundary operators are also discussed.

  5. Continuous modeling of a grain boundary in MgO and its disclination induced grain-boundary migration mechanism

    NASA Astrophysics Data System (ADS)

    Cordier, P.; Sun, X.; Taupin, V.; Fressengeas, C.

    2016-12-01

    Grain boundaries (GBs) are thin material layers where the lattice rotates from one orientation to the next one within a few nanometers. Because they treat these layers as infinitely thin interfaces, large-scale polycrystalline representations fail to describe their structure. Conversely, atomistic representations provide a detailed description of the GBs, but their character remains discrete and not prone to coarse-graining procedures. Continuum descriptions based on kinematic and crystal defect fields defined at interatomic scale are appealing because they can provide smooth and thorough descriptions of GBs, recovering in some sense the atomistic description and potentially serving as a basis for coarse-grained polycrystalline representations. In this work, a crossover between atomistic description and continuous representation of a MgO tilt boundary in polycrystals is set-up to model the periodic arrays of structural units by using dislocation and disclination dipole arrays along GBs. The strain, rotation, curvature, disclination and dislocation density fields are determined in the boundary area by using the discrete atomic positions generated by molecular dynamics simulations. Then, this continuous disclination/dislocation model is used as part of the initial conditions in elasto-plastic continuum mechanics simulations to investigate the shear-coupled boundary migration of tilt boundaries. The present study leads to better understanding of the structure and mechanical architecture of grain boundaries.

  6. Safe corridors for K-wiring in phalangeal fractures.

    PubMed

    Rex, C; Vignesh, R; Javed, M; Balaji, Subba Chandra; Premanand, C; Zakki, Syed Ashfaque

    2015-01-01

    Unstable phalangeal fractures are commonly treated with K-wire fixation. Operative fixation must be used judiciously and with the expectation that the ultimate outcome should be better than the outcome after nonoperative management. It is necessary to achieve a stable fracture fixation and early mobilization. In order to achieve this goal, one should closely understand the safe portals/corridors in hand for K-wire entry for fractures of the phalanges. Safe corridors were defined and tested using a pilot cadaveric and a clinical case study by assessing the outcome. In our prospective case series, 50 patients with 64 phalangeal fractures were treated with closed reduction and K-wires were inserted through safe portals identified by a pilot cadaveric study. On table active finger movement test was done and the results were analyed using radiology, disabilities of the arm, shoulder, and hand (DASH) score and total active motion (TAM). In our study, little finger (n = 28) was the most commonly involved digit. In fracture pattern, transverse (n = 20) and spiral (n = 20) types were common. Proximal phalanx (n = 38) was commonly involved and the common site being the base of the phalanx (n = 28). 47 (95%) patients had excellent TAM and the mean postoperative DASH score was 58.05. All patients achieved excellent and good scores proving the importance of the safe corridor concept. K-wiring through the safe corridor has proved to yield the best clinical results because of least tethering of soft tissues as evidenced by performing "on-table active finger movement test" at the time of surgery. We strongly recommend K-wiring through safe portals in all phalangeal fractures.

  7. Fixating picture boundaries does not eliminate boundary extension: Implications for scene representation

    PubMed Central

    Gagnier, Kristin Michod; Dickinson, Christopher A.; Intraub, Helene

    2015-01-01

    Observers frequently remember seeing more of a scene than was shown (boundary extension). Does this reflect a lack of eye fixations to the boundary region? Single-object photographs were presented for 14–15 s each. Main objects were either whole or slightly cropped by one boundary, creating a salient marker of boundary placement. All participants expected a memory test, but only half were informed that boundary memory would be tested. Participants in both conditions made multiple fixations to the boundary region and the cropped region during study. Demonstrating the importance of these regions, test-informed participants fixated them sooner, longer, and more frequently. Boundary ratings (Experiment 1) and border adjustment tasks (Experiments 2–4) revealed boundary extension in both conditions. The error was reduced, but not eliminated, in the test-informed condition. Surprisingly, test knowledge and multiple fixations to the salient cropped region, during study and at test, were insufficient to overcome boundary extension on the cropped side. Results are discussed within a traditional visual-centric framework versus a multisource model of scene perception. PMID:23547787

  8. Fixating picture boundaries does not eliminate boundary extension: implications for scene representation.

    PubMed

    Michod Gagnier, Kristin; Dickinson, Christopher A; Intraub, Helene

    2013-01-01

    Observers frequently remember seeing more of a scene than was shown (boundary extension). Does this reflect a lack of eye fixations to the boundary region? Single-object photographs were presented for 14-15 s each. Main objects were either whole or slightly cropped by one boundary, creating a salient marker of boundary placement. All participants expected a memory test, but only half were informed that boundary memory would be tested. Participants in both conditions made multiple fixations to the boundary region and the cropped region during study. Demonstrating the importance of these regions, test-informed participants fixated them sooner, longer, and more frequently. Boundary ratings (Experiment 1) and border adjustment tasks (Experiments 2-4) revealed boundary extension in both conditions. The error was reduced, but not eliminated, in the test-informed condition. Surprisingly, test knowledge and multiple fixations to the salient cropped region, during study and at test, were insufficient to overcome boundary extension on the cropped side. Results are discussed within a traditional visual-centric framework versus a multisource model of scene perception.

  9. The safe home project.

    PubMed

    Arphorn, Sara; Jiraniratisai, Sopaphan; Rungtakul, Rungsri; Phutta, Nikom

    2011-12-01

    The Thai Health Promotion Foundation supported the Improvement of Quality of Life of Informal Workers project in Ban Luang District, Amphur Photaram, Ratchaburi Province. There were many informal workers in Ban Luang District. Sweet-crispy fish producers in Ban Luang were the largest group among the sweet-crispy fish producers in Thailand. This project was aimed at improving living and working conditions of informal workers, with a focus on the sweet-crispy fish group. Good practices of improved living and working conditions were used to help informal workers build safe, healthy and productive work environments. These informal workers often worked in substandard conditions and were exposed to various hazards in the working area. These hazards included risk of exposure to hot work environment, ergonomics-related injuries, chemical hazards, electrical hazards etc. Ergonomics problems were commonly in the sweet-crispy fish group. Unnatural postures such as prolonged sitting were performed dominantly. One hundred and fifty informal workers participated in this project. Occupational health volunteers were selected to encourage occupational health and safety in four groups of informal workers in 2009. The occupational health volunteers trained in 2008 were farmers, beauty salon workers and doll makers. The occupational health and safety knowledge is extended to a new informal worker group: sweet-crispy fish producer, in 2009. The occupational health and safety training for sweet-crispy fish group is conducted by occupational health volunteers. The occupational health volunteers increased their skills and knowledge assist in to make safe home and safe community through participatory oriented training. The improvement of living and working condition is conducted by using a modified WISH, Work Improvement for Safe Home, checklist. The plans of improvement were recorded. The informal workers showed improvement mostly on material handling and storage. The safe uses and safe

  10. A safe and reliable neutralization assay based on pseudovirus to measure neutralizing antibody titer against poliovirus.

    PubMed

    Liu, Shaohua; Song, Dongmei; Bai, Han; Lu, Weiwei; Dai, Xinxian; Hao, Chunsheng; Zhang, Zhongyang; Guo, Huijie; Zhang, Yue; Li, Xiuling

    2017-12-01

    With the promotion of inactivated poliomyelitis vaccine (IPV) and live attenuated oral poliomyelitis vaccine (OPV), the global reported cases of poliomyelitis have reduced sharply from 0.35 million in 1988 to 74 in 2015. The Polio Eradication & Endgame Strategic Plan published by WHO in 2013 included the strategy of implementation of poliovirus safe handling and containment measures to minimize the risks of facility-associated reintroduction of virus into the polio-free community to prevent the re-import of poliovirus. Toward this strategy, we produced replication-incompetent pseudovirus of poliovirus type 1, 2, 3 attenuated strains by constructing poliovirus capsid expression vectors and poliovirus replicon then transfecting HEK293T cells and developed a pseudovirus-based neutralization assay (pNA) to determine neutralizing antibody titer which is more secure, time-saving and reliable than conventional neutralization assay (cNA). By using anti-poliovirus rat serum, we demonstrated excellent correlation between neutralizing antibody titers measured by cNA and pNA. It was concluded that pNA can be a potential alternative to replace cNA as a safe and time-saving system for titer determination after live poliovirus's safekeeping. © 2017 Wiley Periodicals, Inc.

  11. Work-family boundary strategies: Stability and alignment between preferred and enacted boundaries.

    PubMed

    Ammons, Samantha K

    2013-02-01

    Are individuals bounding work and family the way they would like? Much of the work-family boundary literature focuses on whether employees are segmenting or integrating work with family, but does not explore the boundaries workers would like to have, nor does it examine the fit between desired and enacted boundaries, or assess boundary stability. In this study, 23 respondents employed at a large Fortune 500 company were interviewed about their work-family boundaries before and after their teams underwent a cultural change initiative that sought to loosen workplace norms and allow employees more autonomy to decide when and where they performed their job tasks. Four distinct boundary strategies emerged from the data, with men and parents of young children having better alignment between preferred and enacted boundaries than women and those without these caregiving duties. Implications for boundary theory and research are discussed.

  12. Work-family boundary strategies: Stability and alignment between preferred and enacted boundaries

    PubMed Central

    Ammons, Samantha K.

    2015-01-01

    Are individuals bounding work and family the way they would like? Much of the work-family boundary literature focuses on whether employees are segmenting or integrating work with family, but does not explore the boundaries workers would like to have, nor does it examine the fit between desired and enacted boundaries, or assess boundary stability. In this study, 23 respondents employed at a large Fortune 500 company were interviewed about their work-family boundaries before and after their teams underwent a cultural change initiative that sought to loosen workplace norms and allow employees more autonomy to decide when and where they performed their job tasks. Four distinct boundary strategies emerged from the data, with men and parents of young children having better alignment between preferred and enacted boundaries than women and those without these caregiving duties. Implications for boundary theory and research are discussed. PMID:25620801

  13. Architectural Blueprint for Plate Boundary Observatories based on interoperable Data Management Platforms

    NASA Astrophysics Data System (ADS)

    Kerschke, D. I.; Häner, R.; Schurr, B.; Oncken, O.; Wächter, J.

    2014-12-01

    Interoperable data management platforms play an increasing role in the advancement of knowledge and technology in many scientific disciplines. Through high quality services they support the establishment of efficient and innovative research environments. Well-designed research environments can facilitate the sustainable utilization, exchange, and re-use of scientific data and functionality by using standardized community models. Together with innovative 3D/4D visualization, these concepts provide added value in improving scientific knowledge-gain, even across the boundaries of disciplines. A project benefiting from the added value is the Integrated Plate boundary Observatory in Chile (IPOC). IPOC is a European-South American network to study earthquakes and deformation at the Chilean continental margin and to monitor the plate boundary system for capturing an anticipated great earthquake in a seismic gap. In contrast to conventional observatories that monitor individual signals only, IPOC captures a large range of different processes through various observation methods (e.g., seismographs, GPS, magneto-telluric sensors, creep-meter, accelerometer, InSAR). For IPOC a conceptual design has been devised that comprises an architectural blueprint for a data management platform based on common and standardized data models, protocols, and encodings as well as on an exclusive use of Free and Open Source Software (FOSS) including visualization components. Following the principles of event-driven service-oriented architectures, the design enables novel processes by sharing and re-using functionality and information on the basis of innovative data mining and data fusion technologies. This platform can help to improve the understanding of the physical processes underlying plate deformations as well as the natural hazards induced by them. Through the use of standards, this blueprint can not only be facilitated for other plate observing systems (e.g., the European Plate

  14. Eigenmode Analysis of Boundary Conditions for One-Dimensional Preconditioned Euler Equations

    NASA Technical Reports Server (NTRS)

    Darmofal, David L.

    1998-01-01

    An analysis of the effect of local preconditioning on boundary conditions for the subsonic, one-dimensional Euler equations is presented. Decay rates for the eigenmodes of the initial boundary value problem are determined for different boundary conditions. Riemann invariant boundary conditions based on the unpreconditioned Euler equations are shown to be reflective with preconditioning, and, at low Mach numbers, disturbances do not decay. Other boundary conditions are investigated which are non-reflective with preconditioning and numerical results are presented confirming the analysis.

  15. Accurate boundary conditions for exterior problems in gas dynamics

    NASA Technical Reports Server (NTRS)

    Hagstrom, Thomas; Hariharan, S. I.

    1988-01-01

    The numerical solution of exterior problems is typically accomplished by introducing an artificial, far field boundary and solving the equations on a truncated domain. For hyperbolic systems, boundary conditions at this boundary are often derived by imposing a principle of no reflection. However, waves with spherical symmetry in gas dynamics satisfy equations where incoming and outgoing Riemann variables are coupled. This suggests that natural reflections may be important. A reflecting boundary condition is proposed based on an asymptotic solution of the far field equations. Nonlinear energy estimates are obtained for the truncated problem and numerical experiments presented to validate the theory.

  16. Accurate boundary conditions for exterior problems in gas dynamics

    NASA Technical Reports Server (NTRS)

    Hagstrom, Thomas; Hariharan, S. I.

    1988-01-01

    The numerical solution of exterior problems is typically accomplished by introducing an artificial, far-field boundary and solving the equations on a truncated domain. For hyperbolic systems, boundary conditions at this boundary are often derived by imposing a principle of no reflection. However, waves with spherical symmetry in gas dynamics satisfy equations where incoming and outgoing Riemann variables are coupled. This suggests that natural reflections may be important. A reflecting boundary condition is proposed based on an asymptotic solution of the far-field equations. Nonlinear energy estimates are obtained for the truncated problem and numerical experiments presented to validate the theory.

  17. Statistical Study of Relations Between the Induced Magnetosphere, Ion Composition, and Pressure Balance Boundaries Around Mars Based On MAVEN Observations

    NASA Astrophysics Data System (ADS)

    Matsunaga, Kazunari; Seki, Kanako; Brain, David A.; Hara, Takuya; Masunaga, Kei; Mcfadden, James P.; Halekas, Jasper S.; Mitchell, David L.; Mazelle, Christian; Espley, J. R.; Gruesbeck, Jacob; Jakosky, Bruce M.

    2017-09-01

    Direct interaction between the solar wind (SW) and the Martian upper atmosphere forms a characteristic region, called the induced magnetosphere between the magnetosheath and the ionosphere. Since the SW deceleration due to increasing mass loading by heavy ions plays an important role in the induced magnetosphere formation, the ion composition is also expected to change around the induced magnetosphere boundary (IMB). Here we report on relations of the IMB, the ion composition boundary (ICB), and the pressure balance boundary based on a statistical analysis of about 8 months of simultaneous ion, electron, and magnetic field observations by Mars Atmosphere and Volatile EvolutioN (MAVEN) mission. We chose the period when MAVEN observed the SW directly near its apoapsis to investigate their dependence on SW parameters. Results show that IMBs almost coincide with ICBs on the dayside and locations of all three boundaries are affected by the SW dynamic pressure. A remarkable feature is that all boundaries tend to locate at higher altitudes in the southern hemisphere than in the northern hemisphere on the nightside. This clear geographical asymmetry is permanently seen regardless of locations of the strong crustal B fields in the southern hemisphere, while the boundary locations become higher when the crustal B fields locate on the dayside. On the nightside, IMBs usually locate at higher altitude than ICBs. However, ICBs are likely to be located above IMBs in the nightside, southern, and downward ESW hemisphere when the strong crustal B fields locate on the dayside.

  18. Implementing AORN recommended practices for a safe environment of care.

    PubMed

    Hughes, Antonia B

    2013-08-01

    Providing a safe environment for every patient undergoing a surgical or other invasive procedure is imperative. AORN's "Recommended practices for a safe environment of care" provides guidance on a wide range of topics related to the safety of perioperative patients and health care personnel. The recommendations are intended to provide guidance for establishing best practices and implementing safety measures in all perioperative practice settings. Perioperative nurses should be aware of risks related to musculoskeletal injuries, fire, equipment, latex, and chemicals, among others, and understand strategies for reducing the risks. Evidence-based recommendations can give practitioners the tools to guide safe practice. Copyright © 2013 AORN, Inc. Published by Elsevier Inc. All rights reserved.

  19. Ontological approach for safe and effective polypharmacy prescription

    PubMed Central

    Grando, Adela; Farrish, Susan; Boyd, Cynthia; Boxwala, Aziz

    2012-01-01

    The intake of multiple medications in patients with various medical conditions challenges the delivery of medical care. Initial empirical studies and pilot implementations seem to indicate that generic safe and effective multi-drug prescription principles could be defined and reused to reduce adverse drug events and to support compliance with medical guidelines and drug formularies. Given that ontologies are known to provide well-principled, sharable, setting-independent and machine-interpretable declarative specification frameworks for modeling and reasoning on biomedical problems, we explore here their use in the context of multi-drug prescription. We propose an ontology for modeling drug-related knowledge and a repository of safe and effective generic prescription principles. To test the usability and the level of granularity of the developed ontology-based specification models and heuristic we implemented a tool that computes the complexity of multi-drug treatments, and a decision aid to check the safeness and effectiveness of prescribed multi-drug treatments. PMID:23304299

  20. SafeConnect Solar - Final Scientific/Technical Report (Updated)

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

    McNish, Zachary

    2016-02-03

    Final Scientific/Technical Report from Tier 0 SunShot Incubator award for hardware-based solution to reducing soft costs of installed solar. The primary objective of this project was for SafeConnect Solar (“SafeConnect”) to create working proof-of-concept hardware prototypes from its proprietary intellectual property and business concepts for a plug-and-play, safety-oriented hardware solution for photovoltaic solar systems. Specifically, SafeConnect sought to build prototypes of its “SmartBox” and related cabling and connectors, as well as the firmware needed to run the hardware. This hardware is designed to ensure a residential PV system installed with it can address all safety concerns that currently form themore » basis of AHJ electrical permitting and licensing requirements, thereby reducing the amount of permitting and specialized labor required on a residential PV system, and also opening up new sales channels and customer acquisition opportunities.« less

  1. Base Pressure at Supersonic Speeds on Two-dimensional Airfoils and on Bodies of Revolution with and Without Fins Having Turbulent Boundary Layers

    NASA Technical Reports Server (NTRS)

    LOVE EUGENE S

    1957-01-01

    An analysis has been made of available experimental data to show the effects of most of the variables that are more predominant in determining base pressure at supersonic speeds. The analysis covers base pressures for two-dimensional airfoils and for bodies of revolution with and without stabilizing fins and is restricted to turbulent boundary layers. The present status of available experimental information is summarized as are the existing methods for predicting base pressure. A simple semiempirical method is presented for estimating base pressure. For two-dimensional bases, this method stems from an analogy established between the base-pressure phenomena and the peak pressure rise associated with the separation of the boundary layer. An analysis made for axially symmetric flow indicates that the base pressure for bodies of revolution is subject to the same analogy. Based upon the methods presented, estimations are made of such effects as Mach number, angle of attack, boattailing, fineness ratio, and fins. These estimations give fair predictions of experimental results. (author)

  2. Leaching boundary movement in solidified/stabilized waste forms

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

    Kuang Ye Cheng; Bishop, P.L.

    1992-02-01

    Investigation of the leaching of cement-based waste forms in acetic acid solutions found that acids attacked the waste form from the surface toward the center. A sharp leaching boundary was identified in every leached sample, using pH color indicators. The movement of the leaching boundary was found to be a single diffusion-controlled process.

  3. Unified anomaly suppression and boundary extraction in laser radar range imagery based on a joint curve-evolution and expectation-maximization algorithm.

    PubMed

    Feng, Haihua; Karl, William Clem; Castañon, David A

    2008-05-01

    In this paper, we develop a new unified approach for laser radar range anomaly suppression, range profiling, and segmentation. This approach combines an object-based hybrid scene model for representing the range distribution of the field and a statistical mixture model for the range data measurement noise. The image segmentation problem is formulated as a minimization problem which jointly estimates the target boundary together with the target region range variation and background range variation directly from the noisy and anomaly-filled range data. This formulation allows direct incorporation of prior information concerning the target boundary, target ranges, and background ranges into an optimal reconstruction process. Curve evolution techniques and a generalized expectation-maximization algorithm are jointly employed as an efficient solver for minimizing the objective energy, resulting in a coupled pair of object and intensity optimization tasks. The method directly and optimally extracts the target boundary, avoiding a suboptimal two-step process involving image smoothing followed by boundary extraction. Experiments are presented demonstrating that the proposed approach is robust to anomalous pixels (missing data) and capable of producing accurate estimation of the target boundary and range values from noisy data.

  4. Passive imaging based multi-cue hazard detection spacecraft safe landing

    NASA Technical Reports Server (NTRS)

    Huertas, Andres; Cheng, Yang; Madison, Richard

    2006-01-01

    Accurate assessment of potentially damaging ground hazards during the spacecraft EDL (Entry, Descent and Landing) phase is crucial to insure a high probability of safe landing. A lander that encounters a large rock, falls off a cliff, or tips over on a steep slope can sustain mission ending damage. Guided entry is expected to shrink landing ellipses from 100-300 km to -10 km radius for the second generation landers as early as 2009. Regardless of size and location, however, landing ellipses will almost always contain hazards such as craters, discontinuities, steep slopes, and large rocks. It is estimated that an MSL (Mars Science Laboratory)-sized lander should detect and avoid 16- 150m diameter craters, vertical drops similar to the edges of 16m or 3.75m diameter crater, for high and low altitude HAD (Hazard Detection and Avoidance) respectively. It should also be able to detect slopes 20' or steeper, and rocks 0.75m or taller. In this paper we will present a passive imaging based, multi-cue hazard detection and avoidance (HDA) system suitable for Martian and other lander missions. This is the first passively imaged HDA system that seamlessly integrates multiple algorithm-crater detection, slope estimation, rock detection and texture analysis, and multicues- crater morphology, rock distribution, to detect these hazards in real time.

  5. Linear segmentation algorithm for detecting layer boundary with lidar.

    PubMed

    Mao, Feiyue; Gong, Wei; Logan, Timothy

    2013-11-04

    The automatic detection of aerosol- and cloud-layer boundary (base and top) is important in atmospheric lidar data processing, because the boundary information is not only useful for environment and climate studies, but can also be used as input for further data processing. Previous methods have demonstrated limitations in defining the base and top, window-size setting, and have neglected the in-layer attenuation. To overcome these limitations, we present a new layer detection scheme for up-looking lidars based on linear segmentation with a reasonable threshold setting, boundary selecting, and false positive removing strategies. Preliminary results from both real and simulated data show that this algorithm cannot only detect the layer-base as accurate as the simple multi-scale method, but can also detect the layer-top more accurately than that of the simple multi-scale method. Our algorithm can be directly applied to uncalibrated data without requiring any additional measurements or window size selections.

  6. Unified bulk-boundary correspondence for band insulators

    NASA Astrophysics Data System (ADS)

    Rhim, Jun-Won; Bardarson, Jens H.; Slager, Robert-Jan

    2018-03-01

    The bulk-boundary correspondence, a topic of intensive research interest over the past decades, is one of the quintessential ideas in the physics of topological quantum matter. Nevertheless, it has not been proven in all generality and has in certain scenarios even been shown to fail, depending on the boundary profiles of the terminated system. Here, we introduce bulk numbers that capture the exact number of in-gap modes, without any such subtleties in one spatial dimension. Similarly, based on these 1D bulk numbers, we define a new 2D winding number, which we call the pole winding number, that specifies the number of robust metallic surface bands in the gap as well as their topological character. The underlying general methodology relies on a simple continuous extrapolation from the bulk to the boundary, while tracking the evolution of Green's function's poles in the vicinity of the bulk band edges. As a main result we find that all the obtained numbers can be applied to the known insulating phases in a unified manner regardless of the specific symmetries. Additionally, from a computational point of view, these numbers can be effectively evaluated without any gauge fixing problems. In particular, we directly apply our bulk-boundary correspondence construction to various systems, including 1D examples without a traditional bulk-boundary correspondence, and predict the existence of boundary modes on various experimentally studied graphene edges, such as open boundaries and grain boundaries. Finally, we sketch the 3D generalization of the pole winding number by in the context of topological insulators.

  7. Assessing the effects of Families for Safe Dates, a family-based teen dating abuse prevention program.

    PubMed

    Foshee, Vangie A; McNaughton Reyes, Heath Luz; Ennett, Susan T; Cance, Jessica D; Bauman, Karl E; Bowling, J Michael

    2012-10-01

    To examine the effects of a family-based teen dating abuse prevention program, Families for Safe Dates, primarily on outcomes related to testing the conceptual underpinnings of the program including (1) factors motivating and facilitating caregiver engagement in teen dating abuse prevention activities, and 2) risk factors for teen dating abuse, and secondarily on dating abuse behaviors. Families were recruited nationwide using listed telephone numbers. Caregivers and teens completed baseline and 3-month follow-up telephone interviews (n = 324). Families randomly allocated to treatment condition received the Families for Safe Dates program including six mailed activity booklets followed-up by health educator telephone calls. There were significant (<.05) treatment effects in hypothesized directions on most of the factors motivating and facilitating caregiver engagement in teen dating abuse prevention activities including caregiver perceived severity of dating abuse, response efficacy for preventing dating abuse, self-efficacy for talking about dating abuse, knowledge of dating abuse, acceptance of dating abuse, communication skills with the teen, and belief in the importance of involvement in their male (but not female) teen's dating. The latter effect was the only one moderated by sex of the teen. The targeted risk factor affected by the program was teen acceptance of dating abuse. Treatment was also significantly associated with less physical dating abuse victimization. Modifications to the program are warranted, but overall, the findings are very favorable for the first family-based teen dating abuse prevention program to be evaluated. Copyright © 2012 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  8. Estimate of safe human exposure levels for lunar dust based on comparative benchmark dose modeling.

    PubMed

    James, John T; Lam, Chiu-Wing; Santana, Patricia A; Scully, Robert R

    2013-04-01

    Brief exposures of Apollo astronauts to lunar dust occasionally elicited upper respiratory irritation; however, no limits were ever set for prolonged exposure to lunar dust. The United States and other space faring nations intend to return to the moon for extensive exploration within a few decades. In the meantime, habitats for that exploration, whether mobile or fixed, must be designed to limit human exposure to lunar dust to safe levels. Herein we estimate safe exposure limits for lunar dust collected during the Apollo 14 mission. We instilled three respirable-sized (∼2 μ mass median diameter) lunar dusts (two ground and one unground) and two standard dusts of widely different toxicities (quartz and TiO₂) into the respiratory system of rats. Rats in groups of six were given 0, 1, 2.5 or 7.5 mg of the test dust in a saline-Survanta® vehicle, and biochemical and cellular biomarkers of toxicity in lung lavage fluid were assayed 1 week and one month after instillation. By comparing the dose--response curves of sensitive biomarkers, we estimated safe exposure levels for astronauts and concluded that unground lunar dust and dust ground by two different methods were not toxicologically distinguishable. The safe exposure estimates were 1.3 ± 0.4 mg/m³ (jet-milled dust), 1.0 ± 0.5 mg/m³ (ball-milled dust) and 0.9 ± 0.3 mg/m³ (unground, natural dust). We estimate that 0.5-1 mg/m³ of lunar dust is safe for periodic human exposures during long stays in habitats on the lunar surface.

  9. Microstructure of a safe-end dissimilar metal weld joint (SA508-52-316L) prepared by narrow-gap GTAW

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

    Ming, Hongliang

    The microstructure, residual strain and interfacial chemical composition distribution of a safe-end dissimilar metal weld joint (DMWJ, SA508-52-316L) prepared by narrow-gap gas-tungsten arc welding (NG-GTAW) were studied by optical microscope (OM) and scanning electron microscope equipped with an energy dispersive X-ray microanalysis (SEM/EDX) and an electron back scattering diffraction (EBSD) system. Complex microstructure and chemical composition distribution are found, especially at the SA508-52 interface and the 52-316L interface. In brief, a complicated microstructure transition exists within the SA508 heat affected zone (HAZ); the residual strain, the fraction of high angle random grain boundaries and low angle boundaries decrease with increasingmore » the distance from the fusion boundary in 316L HAZ; neither typical type II boundary nor obvious carbon-depleted zone is found near the SA508-52 interface; dramatic and complicated changes of the contents of the main elements, Fe, Cr and Ni, are observed at the distinct interfaces, especially at the SA508-52 interface. No carbon concentration is found at the SA508-52 interface. - Highlights: •Residual strain and GBCD change as a function of the distance from FB in 316L HAZ. •Neither type II boundary nor obvious carbon-depleted zone is found in SA508 HAZ. •No carbon concentration is found at the SA508-52 interface. •The middle part of the DMWJ has the highest residual strain.« less

  10. A Ground-Based Profiling Differential Absorption LIDAR System for Measuring CO2 in the Planetary Boundary Layer

    NASA Technical Reports Server (NTRS)

    Andrews, Arlyn E.; Burris, John F.; Abshire, James B.; Krainak, Michael A.; Riris, Haris; Sun, Xiao-Li; Collatz, G. James

    2002-01-01

    Ground-based LIDAR observations can potentially provide continuous profiles of CO2 through the planetary boundary layer and into the free troposphere. We will present initial atmospheric measurements from a prototype system that is based on components developed by the telecommunications industry. Preliminary measurements and instrument performance calculations indicate that an optimized differential absorption LIDAR (DIAL) system will be capable of providing continuous hourly averaged profiles with 250m vertical resolution and better than 1 ppm precision at 1 km. Precision increases (decreases) at lower (higher) altitudes and is directly proportional to altitude resolution and acquisition time. Thus, precision can be improved if temporal or vertical resolution is sacrificed. Our approach measures absorption by CO2 of pulsed laser light at 1.6 microns backscattered from atmospheric aerosols. Aerosol concentrations in the planetary boundary layer are relatively high and are expected to provide adequate signal returns for the desired resolution. The long-term goal of the project is to develop a rugged, autonomous system using only commercially available components that can be replicated inexpensively for deployment in a monitoring network.

  11. Tracking sustainable development with a national barometer for South Africa using a downscaled “safe and just space” framework

    PubMed Central

    Cole, Megan J.; Bailey, Richard M.; New, Mark G.

    2014-01-01

    Nations in the 21st century face a complex mix of environmental and social challenges, as highlighted by the on-going Sustainable Development Goals process. The “planetary boundaries” concept [Rockström J, et al. (2009) Nature 461(7263):472–475], and its extension through the addition of social well-being indicators to create a framework for “safe and just” inclusive sustainable development [Raworth K (2012) Nature Climate Change 2(4):225–226], have received considerable attention in science and policy circles. As the chief aim of this framework is to influence public policy, and this happens largely at the national level, we assess whether it can be used at the national scale, using South Africa as a test case. We developed a decision-based methodology for downscaling the framework and created a national “barometer” for South Africa, combining 20 indicators and boundaries for environmental stress and social deprivation. We find that it is possible to maintain the original design and concept of the framework while making it meaningful in the national context, raising new questions and identifying priority areas for action. Our results show that South Africa has exceeded its environmental boundaries for biodiversity loss, marine harvesting, freshwater use, and climate change, and social deprivation is most severe in the areas of safety, income, and employment. Trends since 1994 show improvement in nearly all social indicators, but progression toward or over boundaries for most environmental indicators. The barometer shows that achieving inclusive sustainable development in South Africa requires national and global action on multiple fronts, and careful consideration of the interplay between different environmental domains and development strategies. PMID:25294930

  12. Effectiveness of a Driving Intervention on Safe Community Mobility for Returning Combat Veterans

    DTIC Science & Technology

    2017-05-01

    study is a follow-on to prior DOD funded work “Efficacy of a Driving Intervention Program on Safe Community Mobility for Combat Veterans”. Funding for...lack of control groups, suggest that a simu- lator-based OT-DI can provide a safe environment for testing and training of CV to reduce dangerous...AWARD NUMBER: W81XWH-15-1-0032 TITLE: Effectiveness of a Driving Intervention on Safe Community Mobility for Returning Combat Veterans

  13. Work-Family Boundary Strategies: Stability and Alignment between Preferred and Enacted Boundaries

    ERIC Educational Resources Information Center

    Ammons, Samantha K.

    2013-01-01

    Are individuals bounding work and family the way they would like? Much of the work-family boundary literature focuses on whether employees are segmenting or integrating work with family, but does not explore the boundaries workers would like to have, nor does it examine the fit between desired and enacted boundaries, or assess boundary stability.…

  14. Precession electron diffraction for SiC grain boundary characterization in unirradiated TRISO fuel

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

    Lillo, T. M.; van Rooyen, I. J.; Wu, Y. Q.

    Precession electron diffraction (PED), a transmission electron microscopy-based technique, has been evaluated for the suitability for evaluating grain boundary character in the SiC layer of tristructural isotropic (TRISO) fuel. Although the ultimate goal is to determine the grain boundary characteristics of fission product containing grain boundaries of neutron irradiated SiC, our work reports the effect of transmission electron microscope (TEM) lamella thickness on quality of data and establishes a baseline comparison on grain boundary characteristics determined previously using a conventional EBSD scanning electron microscope (SEM) based technique. In general, it was determined that the lamella thickness produced using the standardmore » FIB fabrication process, is sufficient to provide reliable PED measurements with thicker lamellae (~120 nm) produce higher quality orientation data. Analysis of grain boundary character from the TEM-based PED data showed a much lower fraction of low angle grain boundaries compared to SEM-based EBSD data from the SiC layer of the same TRISO-coated particle as well as a SiC layer deposited at a slightly lower temperature. The fractions of high angle and CSL-related grain boundaries determined by PED are similar to those found using SEM-based EBSD. Since the grain size of the SiC layer of TRSIO fuel can be as small as 250 nm [12], depending on the fabrication parameters, and grain boundary fission product precipitates can be nano-sized, the TEM-based PED orientation data collection method is preferred to determine an accurate representation of the relative fractions of low angle, high angle and CSL-related grain boundaries. It was concluded that although the resolution of the PED data is better by more than an order of magnitude, data acquisition times may be significantly longer or the number of areas analyzed significantly larger than the SEM-based method to obtain a statistically relevant distribution. Also, grain size could be

  15. Precession electron diffraction for SiC grain boundary characterization in unirradiated TRISO fuel

    DOE PAGES

    Lillo, T. M.; van Rooyen, I. J.; Wu, Y. Q.

    2016-06-16

    Precession electron diffraction (PED), a transmission electron microscopy-based technique, has been evaluated for the suitability for evaluating grain boundary character in the SiC layer of tristructural isotropic (TRISO) fuel. Although the ultimate goal is to determine the grain boundary characteristics of fission product containing grain boundaries of neutron irradiated SiC, our work reports the effect of transmission electron microscope (TEM) lamella thickness on quality of data and establishes a baseline comparison on grain boundary characteristics determined previously using a conventional EBSD scanning electron microscope (SEM) based technique. In general, it was determined that the lamella thickness produced using the standardmore » FIB fabrication process, is sufficient to provide reliable PED measurements with thicker lamellae (~120 nm) produce higher quality orientation data. Analysis of grain boundary character from the TEM-based PED data showed a much lower fraction of low angle grain boundaries compared to SEM-based EBSD data from the SiC layer of the same TRISO-coated particle as well as a SiC layer deposited at a slightly lower temperature. The fractions of high angle and CSL-related grain boundaries determined by PED are similar to those found using SEM-based EBSD. Since the grain size of the SiC layer of TRSIO fuel can be as small as 250 nm [12], depending on the fabrication parameters, and grain boundary fission product precipitates can be nano-sized, the TEM-based PED orientation data collection method is preferred to determine an accurate representation of the relative fractions of low angle, high angle and CSL-related grain boundaries. It was concluded that although the resolution of the PED data is better by more than an order of magnitude, data acquisition times may be significantly longer or the number of areas analyzed significantly larger than the SEM-based method to obtain a statistically relevant distribution. Also, grain size could be

  16. "You're Really Gonna Kick Us All Out?" Sustaining Safe Spaces for Community-Based HIV Prevention and Control among Black Men Who Have Sex with Men.

    PubMed

    Garcia, Jonathan; Parker, Caroline; Parker, Richard G; Wilson, Patrick A; Philbin, Morgan M; Hirsch, Jennifer S

    2015-01-01

    Black men who have sex with men (BMSM) experience among the highest rates of HIV infection in the United States. We conducted a community-based ethnography in New York City to identify the structural and environmental factors that influence BMSMs vulnerability to HIV and their engagement with HIV prevention services. Methods included participant observation at community-based organizations (CBOs) in New York City, in-depth interviews with 31 BMSM, and 17 key informant interviews. Our conceptual framework shows how creating and sustaining safe spaces could be a critical environmental approach to reduce vulnerability to HIV among BMSM. Participant observation, in-depth and key informant interviews revealed that fear and mistrust characterized men's relation to social and public institutions, such as churches, schools, and the police. This fear and mistrust created HIV vulnerability among the BMSM in our sample by challenging engagement with services. Our findings suggest that to be successful, HIV prevention efforts must address these structural and environmental vulnerabilities. Among the CBOs that we studied, "safe spaces" emerged as an important tool for addressing these environmental vulnerabilities. CBOs used safe spaces to provide social support, to address stigma, to prepare men for the workforce, and to foster a sense of community among BMSM. In addition, safe spaces were used for HIV and STI testing and treatment campaigns. Our ethnographic findings suggest that safe spaces represent a promising but so far under-utilized part of HIV prevention infrastructure. Safe spaces seem integral to high impact comprehensive HIV prevention efforts, and may be considered more appropriately as part of HIV capacity-building rather than being nested within program-specific funding structures.

  17. Development of Safe and Effective Botanical Dietary Supplements

    PubMed Central

    2015-01-01

    Regulated differently than drugs or foods, the market for botanical dietary supplements continues to grow worldwide. The recently implemented U.S. FDA regulation that all botanical dietary supplements must be produced using good manufacturing practice is an important step toward enhancing the safety of these products, but additional safeguards could be implemented, and unlike drugs, there are currently no efficacy requirements. To ensure a safe and effective product, botanical dietary supplements should be developed in a manner analogous to pharmaceuticals that involves identification of mechanisms of action and active constituents, chemical standardization based on the active compounds, biological standardization based on pharmacological activity, preclinical evaluation of toxicity and potential for drug–botanical interactions, metabolism of active compounds, and finally, clinical studies of safety and efficacy. Completing these steps will enable the translation of botanicals from the field to safe human use as dietary supplements. PMID:26125082

  18. SU-E-I-97: Smart Auto-Planning Framework in An EMR Environment (SAFEE)

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

    Zhang, B; Chen, S; Mutaf, Y

    2014-06-01

    Purpose: Our Radiation Oncology Department uses clinical practice guidelines for patient treatment, including normal tissue sparing and other dosimetric constraints. These practice guidelines were adapted from national guidelines, clinical trials, literature reviews, and practitioner's own experience. Modern treatment planning systems (TPS) have the capability of incorporating these practice guidelines to automatically create radiation therapy treatment plans with little human intervention. We are developing a software infrastructure to integrate clinical practice guidelines and radiation oncology electronic medical record (EMR) system into radiation therapy treatment planning system (TPS) for auto planning. Methods: Our Smart Auto-Planning Framework in an EMR environment (SAFEE) usesmore » a software pipeline framework to integrate practice guidelines,EMR, and TPS together. The SAFEE system starts with retrieving diagnosis information and physician's prescription from the EMR system. After approval of contouring, SAFEE will automatically create plans according to our guidelines. Based on clinical objectives, SAFEE will automatically select treatment delivery techniques (such as, 3DRT/IMRT/VMAT) and optimize plans. When necessary, SAFEE will create multiple treatment plans with different combinations of parameters. SAFEE's pipeline structure makes it very flexible to integrate various techniques, such as, Model-Base Segmentation (MBS) and plan optimization algorithms, e.g., Multi-Criteria Optimization (MCO). In addition, SAFEE uses machine learning, data mining techniques, and an integrated database to create clinical knowledgebase and then answer clinical questions, such as, how to score plan quality or how volume overlap affects physicians' decision in beam and treatment technique selection. Results: In our institution, we use Varian Aria EMR system and RayStation TPS from RaySearch, whose ScriptService API allows control by external programs. These

  19. Generating land cover boundaries from remotely sensed data using object-based image analysis: overview and epidemiological application.

    PubMed

    Maxwell, Susan K

    2010-12-01

    Satellite imagery and aerial photography represent a vast resource to significantly enhance environmental mapping and modeling applications for use in understanding spatio-temporal relationships between environment and health. Deriving boundaries of land cover objects, such as trees, buildings, and crop fields, from image data has traditionally been performed manually using a very time consuming process of hand digitizing. Boundary detection algorithms are increasingly being applied using object-based image analysis (OBIA) technology to automate the process. The purpose of this paper is to present an overview and demonstrate the application of OBIA for delineating land cover features at multiple scales using a high resolution aerial photograph (1 m) and a medium resolution Landsat image (30 m) time series in the context of a pesticide spray drift exposure application. Copyright © 2010. Published by Elsevier Ltd.

  20. Generating land cover boundaries from remotely sensed data using object-based image analysis: overview and epidemiological application

    PubMed Central

    Maxwell, Susan K.

    2010-01-01

    Satellite imagery and aerial photography represent a vast resource to significantly enhance environmental mapping and modeling applications for use in understanding spatio-temporal relationships between environment and health. Deriving boundaries of land cover objects, such as trees, buildings, and crop fields, from image data has traditionally been performed manually using a very time consuming process of hand digitizing. Boundary detection algorithms are increasingly being applied using object-based image analysis (OBIA) technology to automate the process. The purpose of this paper is to present an overview and demonstrate the application of OBIA for delineating land cover features at multiple scales using a high resolution aerial photograph (1 m) and a medium resolution Landsat image (30 m) time series in the context of a pesticide spray drift exposure application. PMID:21135917

  1. An approach for automated fault diagnosis based on a fuzzy decision tree and boundary analysis of a reconstructed phase space.

    PubMed

    Aydin, Ilhan; Karakose, Mehmet; Akin, Erhan

    2014-03-01

    Although reconstructed phase space is one of the most powerful methods for analyzing a time series, it can fail in fault diagnosis of an induction motor when the appropriate pre-processing is not performed. Therefore, boundary analysis based a new feature extraction method in phase space is proposed for diagnosis of induction motor faults. The proposed approach requires the measurement of one phase current signal to construct the phase space representation. Each phase space is converted into an image, and the boundary of each image is extracted by a boundary detection algorithm. A fuzzy decision tree has been designed to detect broken rotor bars and broken connector faults. The results indicate that the proposed approach has a higher recognition rate than other methods on the same dataset. © 2013 ISA Published by ISA All rights reserved.

  2. The turbulent plasmasphere boundary layer and the outer radiation belt boundary

    NASA Astrophysics Data System (ADS)

    Mishin, Evgeny; Sotnikov, Vladimir

    2017-12-01

    We report on observations of enhanced plasma turbulence and hot particle distributions in the plasmasphere boundary layer formed by reconnection-injected hot plasma jets entering the plasmasphere. The data confirm that the electron pressure peak is formed just outward of the plasmapause in the premidnight sector. Free energy for plasma wave excitation comes from diamagnetic ion currents near the inner edge of the boundary layer due to the ion pressure gradient, electron diamagnetic currents in the entry layer near the electron plasma sheet boundary, and anisotropic (sometimes ring-like) ion distributions revealed inside, and further inward of, the inner boundary. We also show that nonlinear parametric coupling between lower oblique resonance and fast magnetosonic waves significantly contributes to the VLF whistler wave spectrum in the plasmasphere boundary layer. These emissions represent a distinctive subset of substorm/storm-related VLF activity in the region devoid of substorm injected tens keV electrons and could be responsible for the alteration of the outer radiation belt boundary during (sub)storms.

  3. Using Opioids Safely After Surgery

    MedlinePlus

    ... Adult , Geriatric Using Opioids Safely After Surgery Using Opioids Safely After Surgery Stick to the lowest dose ... need opioid pain medicine. If your doctor says opioids aren’t necessary. If your doctor thinks you ...

  4. Vision-based weld pool boundary extraction and width measurement during keyhole fiber laser welding

    NASA Astrophysics Data System (ADS)

    Luo, Masiyang; Shin, Yung C.

    2015-01-01

    In keyhole fiber laser welding processes, the weld pool behavior is essential to determining welding quality. To better observe and control the welding process, the accurate extraction of the weld pool boundary as well as the width is required. This work presents a weld pool edge detection technique based on an off axial green illumination laser and a coaxial image capturing system that consists of a CMOS camera and optic filters. According to the difference of image quality, a complete developed edge detection algorithm is proposed based on the local maximum gradient of greyness searching approach and linear interpolation. The extracted weld pool geometry and the width are validated by the actual welding width measurement and predictions by a numerical multi-phase model.

  5. How Safe Is Safe Enough for Self-Driving Vehicles?

    PubMed

    Liu, Peng; Yang, Run; Xu, Zhigang

    2018-05-21

    Self-driving vehicles (SDVs) promise to considerably reduce traffic crashes. One pressing concern facing the public, automakers, and governments is "How safe is safe enough for SDVs?" To answer this question, a new expressed-preference approach was proposed for the first time to determine the socially acceptable risk of SDVs. In our between-subject survey (N = 499), we determined the respondents' risk-acceptance rate of scenarios with varying traffic-risk frequencies to examine the logarithmic relationships between the traffic-risk frequency and risk-acceptance rate. Logarithmic regression models of SDVs were compared to those of human-driven vehicles (HDVs); the results showed that SDVs were required to be safer than HDVs. Given the same traffic-risk-acceptance rates for SDVs and HDVs, their associated acceptable risk frequencies of SDVs and HDVs were predicted and compared. Two risk-acceptance criteria emerged: the tolerable risk criterion, which indicates that SDVs should be four to five times as safe as HDVs, and the broadly acceptable risk criterion, which suggests that half of the respondents hoped that the traffic risk of SDVs would be two orders of magnitude lower than the current estimated traffic risk. The approach and these results could provide insights for government regulatory authorities for establishing clear safety requirements for SDVs. © 2018 Society for Risk Analysis.

  6. A Method for Extracting Road Boundary Information from Crowdsourcing Vehicle GPS Trajectories.

    PubMed

    Yang, Wei; Ai, Tinghua; Lu, Wei

    2018-04-19

    Crowdsourcing trajectory data is an important approach for accessing and updating road information. In this paper, we present a novel approach for extracting road boundary information from crowdsourcing vehicle traces based on Delaunay triangulation (DT). First, an optimization and interpolation method is proposed to filter abnormal trace segments from raw global positioning system (GPS) traces and interpolate the optimization segments adaptively to ensure there are enough tracking points. Second, constructing the DT and the Voronoi diagram within interpolated tracking lines to calculate road boundary descriptors using the area of Voronoi cell and the length of triangle edge. Then, the road boundary detection model is established integrating the boundary descriptors and trajectory movement features (e.g., direction) by DT. Third, using the boundary detection model to detect road boundary from the DT constructed by trajectory lines, and a regional growing method based on seed polygons is proposed to extract the road boundary. Experiments were conducted using the GPS traces of taxis in Beijing, China, and the results show that the proposed method is suitable for extracting the road boundary from low-frequency GPS traces, multi-type road structures, and different time intervals. Compared with two existing methods, the automatically extracted boundary information was proved to be of higher quality.

  7. A Method for Extracting Road Boundary Information from Crowdsourcing Vehicle GPS Trajectories

    PubMed Central

    Yang, Wei

    2018-01-01

    Crowdsourcing trajectory data is an important approach for accessing and updating road information. In this paper, we present a novel approach for extracting road boundary information from crowdsourcing vehicle traces based on Delaunay triangulation (DT). First, an optimization and interpolation method is proposed to filter abnormal trace segments from raw global positioning system (GPS) traces and interpolate the optimization segments adaptively to ensure there are enough tracking points. Second, constructing the DT and the Voronoi diagram within interpolated tracking lines to calculate road boundary descriptors using the area of Voronoi cell and the length of triangle edge. Then, the road boundary detection model is established integrating the boundary descriptors and trajectory movement features (e.g., direction) by DT. Third, using the boundary detection model to detect road boundary from the DT constructed by trajectory lines, and a regional growing method based on seed polygons is proposed to extract the road boundary. Experiments were conducted using the GPS traces of taxis in Beijing, China, and the results show that the proposed method is suitable for extracting the road boundary from low-frequency GPS traces, multi-type road structures, and different time intervals. Compared with two existing methods, the automatically extracted boundary information was proved to be of higher quality. PMID:29671792

  8. Safe delivery of optical power from space.

    PubMed

    Smith, M; Fork, R L; Cole, S

    2001-05-07

    More than a billion gigawatts of sunlight pass through the area extending from Earth out to geostationary orbit. A small fraction of this clean renewable power appears more than adequate to satisfy the projected needs of Earth, and of human exploration and development of space far into the future. Recent studies suggest safe and efficient access to this power can be achieved within 10 to 40 years. Light, enhanced in spatial and temporal coherence, as compared to natural sunlight, offers a means, and probably the only practical means, of usefully transmitting this power to Earth. We describe safety standards for satellite constellations and Earth based sites designed, respectively, to transmit, and receive this power. The spectral properties, number of satellites, and angle subtended at Earth that are required for safe delivery are identified and discussed.

  9. Emotional boundary work in advanced fertility nursing roles.

    PubMed

    Allan, Helen; Barber, Debbie

    2005-07-01

    In this article we examine the nature of intimacy and knowing in the nurse-patient relationship in the context of advanced nursing roles in fertility care. We suggest that psychoanalytical approaches to emotions may contribute to an increased understanding of how emotions are managed in advanced nursing roles. These roles include nurses undertaking tasks that were formerly performed by doctors. Rather than limiting the potential for intimacy between nurses and fertility patients, we argue that such roles allow nurses to provide increased continuity of care. This facilitates the management of emotions where a feeling of closeness is created while at the same time maintaining a distance or safe boundary with which both nurses and patients are comfortable. We argue that this distanced or 'bounded' relationship can be understood as a defence against the anxiety of emotions raised in the nurse-fertility patient relationship.

  10. Approximate Boundaries for West Lake Landfill, Missouri, 2014, EPA REG 07

    EPA Pesticide Factsheets

    This ESRI File Geodatabase Feature Class contains polygons for GIS depicting the approximate boundaries for West Lake Landfill (MOD079900932), Missouri, 2014, EPA REG 07These polygons are for graphically representing the site. The estimated boundary was developed using St. Louis County Parcels (2014). The boundaries of the individual landfill cells and areas within the site are interpolated based on sample results from the Remedial Investigation Report, ??EMSI, 2000, Remedial Investigation Report, West Lake Landfill Operable Unit 1, April 10.??Boundaries for Operational Units derived from CAD drawings provided by Aquaterra Environmental Solutions, Inc based on work provided by Herst & Associates Inc. and published in the Record of Decision, West Lake Landfill Site, Bridgeton, Missouri, Operable Unit 2, July 2008. CERCLIS ID MOD079900932.

  11. Spatially averaged flow over a wavy boundary revisited

    USGS Publications Warehouse

    McLean, S.R.; Wolfe, S.R.; Nelson, J.M.

    1999-01-01

    Vertical profiles of streamwise velocity measured over bed forms are commonly used to deduce boundary shear stress for the purpose of estimating sediment transport. These profiles may be derived locally or from some sort of spatial average. Arguments for using the latter procedure are based on the assumption that spatial averaging of the momentum equation effectively removes local accelerations from the problem. Using analogies based on steady, uniform flows, it has been argued that the spatially averaged velocity profiles are approximately logarithmic and can be used to infer values of boundary shear stress. This technique of using logarithmic profiles is investigated using detailed laboratory measurements of flow structure and boundary shear stress over fixed two-dimensional bed forms. Spatial averages over the length of the bed form of mean velocity measurements at constant distances from the mean bed elevation yield vertical profiles that are highly logarithmic even though the effect of the bottom topography is observed throughout the water column. However, logarithmic fits of these averaged profiles do not yield accurate estimates of the measured total boundary shear stress. Copyright 1999 by the American Geophysical Union.

  12. Colloidal crystal grain boundary formation and motion

    PubMed Central

    Edwards, Tara D.; Yang, Yuguang; Beltran-Villegas, Daniel J.; Bevan, Michael A.

    2014-01-01

    The ability to assemble nano- and micro- sized colloidal components into highly ordered configurations is often cited as the basis for developing advanced materials. However, the dynamics of stochastic grain boundary formation and motion have not been quantified, which limits the ability to control and anneal polycrystallinity in colloidal based materials. Here we use optical microscopy, Brownian Dynamic simulations, and a new dynamic analysis to study grain boundary motion in quasi-2D colloidal bicrystals formed within inhomogeneous AC electric fields. We introduce “low-dimensional” models using reaction coordinates for condensation and global order that capture first passage times between critical configurations at each applied voltage. The resulting models reveal that equal sized domains at a maximum misorientation angle show relaxation dominated by friction limited grain boundary diffusion; and in contrast, asymmetrically sized domains with less misorientation display much faster grain boundary migration due to significant thermodynamic driving forces. By quantifying such dynamics vs. compression (voltage), kinetic bottlenecks associated with slow grain boundary relaxation are understood, which can be used to guide the temporal assembly of defect-free single domain colloidal crystals. PMID:25139760

  13. Central role of TiO2 anatase grain boundaries on resistivity of CaCu3Ti4O12-based materials probed by Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    De Almeida-Didry, Sonia; Autret, Cécile; Honstettre, Christophe; Lucas, Anthony; Zaghrioui, Mustapha; Pacreau, François; Gervais, François

    2016-11-01

    This study focuses on characterization and control of grain boundaries to enhance the properties of CaCu3Ti4O12 (CCTO) ceramics capacitors for industrial applications. A novel factor deals with TiO2 anatase revealed by Raman scattering in grain boundaries, found as a dominant parameter of largest sample resistivity, consistent with higher grain boundary resistivity and higher breakdown voltage. Four selected samples of CCTO-based compositions showing very different properties in terms of permittivity ranging from 1000 to 684 000 measured at 1 kHz, capacitance of grain boundaries ranging from 8 10-10 to 4.5 10-7 F cm-1, grain boundary resistivity ranging from 193 to 30,000,000 Ω cm and sample resistivity extending from 450 to 1011 Ω cm. The relationship between permittivity weighted by grain size and capacitance of grain boundaries confirms the internal barrier layer capacitance model over 5 orders of magnitude.

  14. How to Safely Give Acetaminophen

    MedlinePlus

    ... Educators Search English Español How to Safely Give Acetaminophen KidsHealth / For Parents / How to Safely Give Acetaminophen ... without getting a doctor's OK first. What Is Acetaminophen Also Called? Acetaminophen is the generic name of ...

  15. Boundary Avoidance Tracking: Consequences (and Uses) of Imposed Boundaries on Pilot-Aircraft Performance

    DTIC Science & Technology

    2009-03-01

    BOUNDARY AVOIDANCE TRACKING: CONSEQUENCES (AND USES) OF IMPOSED BOUNDARIES ON PILOT-AIRCRAFT...States Government. AFIT/GAE/ENY/09-M03 BOUNDARY AVOIDANCE TRACKING: CONSEQUENCES (AND USES) OF IMPOSED BOUNDARIES ON PILOT-AIRCRAFT PERFORMANCE...Case 2 (Gray, 2005) ....................................... 20 Figure 8. Effect of BAT Parameters on Tracking Success (Gray, 2005

  16. Evaluation of the safety performance of highway alignments based on fault tree analysis and safety boundaries.

    PubMed

    Chen, Yikai; Wang, Kai; Xu, Chengcheng; Shi, Qin; He, Jie; Li, Peiqing; Shi, Ting

    2018-05-19

    To overcome the limitations of previous highway alignment safety evaluation methods, this article presents a highway alignment safety evaluation method based on fault tree analysis (FTA) and the characteristics of vehicle safety boundaries, within the framework of dynamic modeling of the driver-vehicle-road system. Approaches for categorizing the vehicle failure modes while driving on highways and the corresponding safety boundaries were comprehensively investigated based on vehicle system dynamics theory. Then, an overall crash probability model was formulated based on FTA considering the risks of 3 failure modes: losing steering capability, losing track-holding capability, and rear-end collision. The proposed method was implemented on a highway segment between Bengbu and Nanjing in China. A driver-vehicle-road multibody dynamics model was developed based on the 3D alignments of the Bengbu to Nanjing section of Ning-Luo expressway using Carsim, and the dynamics indices, such as sideslip angle and, yaw rate were obtained. Then, the average crash probability of each road section was calculated with a fixed-length method. Finally, the average crash probability was validated against the crash frequency per kilometer to demonstrate the accuracy of the proposed method. The results of the regression analysis and correlation analysis indicated good consistency between the results of the safety evaluation and the crash data and that it outperformed the safety evaluation methods used in previous studies. The proposed method has the potential to be used in practical engineering applications to identify crash-prone locations and alignment deficiencies on highways in the planning and design phases, as well as those in service.

  17. Sensitivity to volcanic field boundary

    NASA Astrophysics Data System (ADS)

    Runge, Melody; Bebbington, Mark; Cronin, Shane; Lindsay, Jan; Rashad Moufti, Mohammed

    2016-04-01

    Volcanic hazard analyses are desirable where there is potential for future volcanic activity to affect a proximal population. This is frequently the case for volcanic fields (regions of distributed volcanism) where low eruption rates, fertile soil, and attractive landscapes draw populations to live close by. Forecasting future activity in volcanic fields almost invariably uses spatial or spatio-temporal point processes with model selection and development based on exploratory analyses of previous eruption data. For identifiability reasons, spatio-temporal processes, and practically also spatial processes, the definition of a spatial region is required to which volcanism is confined. However, due to the complex and predominantly unknown sub-surface processes driving volcanic eruptions, definition of a region based solely on geological information is currently impossible. Thus, the current approach is to fit a shape to the known previous eruption sites. The class of boundary shape is an unavoidable subjective decision taken by the forecaster that is often overlooked during subsequent analysis of results. This study shows the substantial effect that this choice may have on even the simplest exploratory methods for hazard forecasting, illustrated using four commonly used exploratory statistical methods and two very different regions: the Auckland Volcanic Field, New Zealand, and Harrat Rahat, Kingdom of Saudi Arabia. For Harrat Rahat, sensitivity of results to boundary definition is substantial. For the Auckland Volcanic Field, the range of options resulted in similar shapes, nevertheless, some of the statistical tests still showed substantial variation in results. This work highlights the fact that when carrying out any hazard analysis on volcanic fields, it is vital to specify how the volcanic field boundary has been defined, assess the sensitivity of boundary choice, and to carry these assumptions and related uncertainties through to estimates of future activity and

  18. Experiment-based modelling of grain boundary β-phase (Mg2Al3) evolution during sensitisation of aluminium alloy AA5083.

    PubMed

    Zhang, R; Steiner, M A; Agnew, S R; Kairy, S K; Davies, C H J; Birbilis, N

    2017-06-07

    An empirical model for the evolution of β-phase (Mg 2 Al 3 ) along grain boundaries in aluminium alloy AA5083 (Al-Mg-Mn) during isothermal exposures is proposed herein. Developing a quantitative understanding of grain boundary precipitation is important to interpreting intergranular corrosion and stress corrosion cracking in this alloy system. To date, complete ab initio models for grain boundary precipitation based upon fundamental principles of thermodynamics and kinetics are not available, despite the critical role that such precipitates play in dictating intergranular corrosion phenomena. Empirical models can therefore serve an important role in advancing the understanding of grain boundary precipitation kinetics, which is an approach applicable beyond the present context. High resolution scanning electron microscopy was to quantify the size and distribution of β-phase precipitates on Ga-embrittled intergranular fracture surfaces of AA5083. The results are compared with the degree of sensitisation (DoS) as judged by nitric acid mass loss testing (ASTM-G67-04), and discussed with models for sensitisation in 5xxx series Al-alloys. The work herein allows sensitisation to be quantified from an unambiguous microstructural perspective.

  19. Two-dimensional fracture analysis of piezoelectric material based on the scaled boundary node method

    NASA Astrophysics Data System (ADS)

    Shen-Shen, Chen; Juan, Wang; Qing-Hua, Li

    2016-04-01

    A scaled boundary node method (SBNM) is developed for two-dimensional fracture analysis of piezoelectric material, which allows the stress and electric displacement intensity factors to be calculated directly and accurately. As a boundary-type meshless method, the SBNM employs the moving Kriging (MK) interpolation technique to an approximate unknown field in the circumferential direction and therefore only a set of scattered nodes are required to discretize the boundary. As the shape functions satisfy Kronecker delta property, no special techniques are required to impose the essential boundary conditions. In the radial direction, the SBNM seeks analytical solutions by making use of analytical techniques available to solve ordinary differential equations. Numerical examples are investigated and satisfactory solutions are obtained, which validates the accuracy and simplicity of the proposed approach. Project supported by the National Natural Science Foundation of China (Grant Nos. 11462006 and 21466012), the Foundation of Jiangxi Provincial Educational Committee, China (Grant No. KJLD14041), and the Foundation of East China Jiaotong University, China (Grant No. 09130020).

  20. Boundary layer temperature measurements of a noctual urban boundary layer

    NASA Astrophysics Data System (ADS)

    Holloway, Simon; Ricketts, Hugo; Vaughan, Geraint

    2018-04-01

    A low-power lidar system based in Manchester, United Kingdom has been developed to measure temperature profiles in the nocturnal urban boundary layer. The lidar transmitter uses a 355nm diode-pumped solid state Nd:YAG laser and two narrow-band interference filters in the receiver filter out rotational Raman lines that are dependent on temperature. The spectral response of the lidar is calibrated using a monochromator. Temperature profiles measured by the system are calibrated by comparison to co-located radiosondes.

  1. Higher modes of the Orr-Sommerfeld problem for boundary layer flows

    NASA Technical Reports Server (NTRS)

    Lakin, W. D.; Grosch, C. E.

    1983-01-01

    The discrete spectrum of the Orr-Sommerfeld problem of hydrodynamic stability for boundary layer flows in semi-infinite regions is examined. Related questions concerning the continuous spectrum are also addressed. Emphasis is placed on the stability problem for the Blasius boundary layer profile. A general theoretical result is given which proves that the discrete spectrum of the Orr-Sommerfeld problem for boundary layer profiles (U(y), 0,0) has only a finite number of discrete modes when U(y) has derivatives of all orders. Details are given of a highly accurate numerical technique based on collocation with splines for the calculation of stability characteristics. The technique includes replacement of 'outer' boundary conditions by asymptotic forms based on the proper large parameter in the stability problem. Implementation of the asymptotic boundary conditions is such that there is no need to make apriori distinctions between subcases of the discrete spectrum or between the discrete and continuous spectrums. Typical calculations for the usual Blasius problem are presented.

  2. Implementation of Slater Boundary Condition into OVERFLOW

    NASA Astrophysics Data System (ADS)

    Duncan, Sean

    Bleed is one of the primary methods of controlling the flow within a mixed compression inlet. In this work the Slater boundary condition, first applied in WindUS, is implemented in OVERFLOW. Further, a simulation using discrete holes is run in order to show the differences between use of the boundary condition and use of the bleed hole geometry. Recent tests at Wright Patterson Air Force Base seek to provide a baseline for study of mixed compression inlets. The inlet used by the Air Force Research Laboratory is simulated in the modified OVERFLOW. The results from the experiment are compared to the CFD to qualitatively assess the accuracy of the simulations. The boundary condition is shown to be robust and viable in studying bleed.

  3. Orbiter Boundary Layer Transition Prediction Tool Enhancements

    NASA Technical Reports Server (NTRS)

    Berry, Scott A.; King, Rudolph A.; Kegerise, Michael A.; Wood, William A.; McGinley, Catherine B.; Berger, Karen T.; Anderson, Brian P.

    2010-01-01

    Updates to an analytic tool developed for Shuttle support to predict the onset of boundary layer transition resulting from thermal protection system damage or repair are presented. The boundary layer transition tool is part of a suite of tools that analyze the local aerothermodynamic environment to enable informed disposition of damage for making recommendations to fly as is or to repair. Using mission specific trajectory information and details of each d agmea site or repair, the expected time (and thus Mach number) of transition onset is predicted to help define proper environments for use in subsequent thermal and stress analysis of the thermal protection system and structure. The boundary layer transition criteria utilized within the tool were updated based on new local boundary layer properties obtained from high fidelity computational solutions. Also, new ground-based measurements were obtained to allow for a wider parametric variation with both protuberances and cavities and then the resulting correlations were calibrated against updated flight data. The end result is to provide correlations that allow increased confidence with the resulting transition predictions. Recently, a new approach was adopted to remove conservatism in terms of sustained turbulence along the wing leading edge. Finally, some of the newer flight data are also discussed in terms of how these results reflect back on the updated correlations.

  4. Parametric boundary reconstruction algorithm for industrial CT metrology application.

    PubMed

    Yin, Zhye; Khare, Kedar; De Man, Bruno

    2009-01-01

    High-energy X-ray computed tomography (CT) systems have been recently used to produce high-resolution images in various nondestructive testing and evaluation (NDT/NDE) applications. The accuracy of the dimensional information extracted from CT images is rapidly approaching the accuracy achieved with a coordinate measuring machine (CMM), the conventional approach to acquire the metrology information directly. On the other hand, CT systems generate the sinogram which is transformed mathematically to the pixel-based images. The dimensional information of the scanned object is extracted later by performing edge detection on reconstructed CT images. The dimensional accuracy of this approach is limited by the grid size of the pixel-based representation of CT images since the edge detection is performed on the pixel grid. Moreover, reconstructed CT images usually display various artifacts due to the underlying physical process and resulting object boundaries from the edge detection fail to represent the true boundaries of the scanned object. In this paper, a novel algorithm to reconstruct the boundaries of an object with uniform material composition and uniform density is presented. There are three major benefits in the proposed approach. First, since the boundary parameters are reconstructed instead of image pixels, the complexity of the reconstruction algorithm is significantly reduced. The iterative approach, which can be computationally intensive, will be practical with the parametric boundary reconstruction. Second, the object of interest in metrology can be represented more directly and accurately by the boundary parameters instead of the image pixels. By eliminating the extra edge detection step, the overall dimensional accuracy and process time can be improved. Third, since the parametric reconstruction approach shares the boundary representation with other conventional metrology modalities such as CMM, boundary information from other modalities can be directly

  5. Global stability analysis of axisymmetric boundary layer over a circular cylinder

    NASA Astrophysics Data System (ADS)

    Bhoraniya, Ramesh; Vinod, Narayanan

    2018-05-01

    This paper presents a linear global stability analysis of the incompressible axisymmetric boundary layer on a circular cylinder. The base flow is parallel to the axis of the cylinder at inflow boundary. The pressure gradient is zero in the streamwise direction. The base flow velocity profile is fully non-parallel and non-similar in nature. The boundary layer grows continuously in the spatial directions. Linearized Navier-Stokes (LNS) equations are derived for the disturbance flow quantities in the cylindrical polar coordinates. The LNS equations along with homogeneous boundary conditions forms a generalized eigenvalues problem. Since the base flow is axisymmetric, the disturbances are periodic in azimuthal direction. Chebyshev spectral collocation method and Arnoldi's iterative algorithm is used for the solution of the general eigenvalues problem. The global temporal modes are computed for the range of Reynolds numbers and different azimuthal wave numbers. The largest imaginary part of the computed eigenmodes is negative, and hence, the flow is temporally stable. The spatial structure of the eigenmodes shows that the disturbance amplitudes grow in size and magnitude while they are moving towards downstream. The global modes of axisymmetric boundary layer are more stable than that of 2D flat-plate boundary layer at low Reynolds number. However, at higher Reynolds number they approach 2D flat-plate boundary layer. Thus, the damping effect of transverse curvature is significant at low Reynolds number. The wave-like nature of the disturbance amplitudes is found in the streamwise direction for the least stable eigenmodes.

  6. Walsh-Hadamard transform kernel-based feature vector for shot boundary detection.

    PubMed

    Lakshmi, Priya G G; Domnic, S

    2014-12-01

    Video shot boundary detection (SBD) is the first step of video analysis, summarization, indexing, and retrieval. In SBD process, videos are segmented into basic units called shots. In this paper, a new SBD method is proposed using color, edge, texture, and motion strength as vector of features (feature vector). Features are extracted by projecting the frames on selected basis vectors of Walsh-Hadamard transform (WHT) kernel and WHT matrix. After extracting the features, based on the significance of the features, weights are calculated. The weighted features are combined to form a single continuity signal, used as input for Procedure Based shot transition Identification process (PBI). Using the procedure, shot transitions are classified into abrupt and gradual transitions. Experimental results are examined using large-scale test sets provided by the TRECVID 2007, which has evaluated hard cut and gradual transition detection. To evaluate the robustness of the proposed method, the system evaluation is performed. The proposed method yields F1-Score of 97.4% for cut, 78% for gradual, and 96.1% for overall transitions. We have also evaluated the proposed feature vector with support vector machine classifier. The results show that WHT-based features can perform well than the other existing methods. In addition to this, few more video sequences are taken from the Openvideo project and the performance of the proposed method is compared with the recent existing SBD method.

  7. A positive view on road safety: Can 'car karma' contribute to safe driving styles?

    PubMed

    Kleisen, Lucienne M B

    2013-01-01

    Many studies in the field of road safety are occupied with studying road unsafety since it generally concentrates on traffic crashes, crash, risk, and aberrant driving behaviour, especially in relation to young drivers. However, this study shows there is scope for thinking about driving and driver training from a different vantage point, that is in terms of safe or normal driving. The findings are reported from four group interviews with young drivers (18-25 years of age); the young drivers discussed their ideas of safe driving and their reasons for using (or not using) safe driving styles. The data show a type of optimistic thinking among young drivers which they call 'car karma'. This finding offers an opportunity to reconceptualise driving in a way that is focused on normal, safe driving styles, a topic that has received less attention in the past. The paper argues that greater focus on safe driving styles could be more conducive to young drivers actually driving safely than focusing on, for instance, crashes, which on an individual level are relatively rare (Elander et al., 1993, p. 277). Based on empirical research, the first positively stated definition of road safety is proposed based on the notion of 'car karma'. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Boundary holographic Witten diagrams

    DOE PAGES

    Karch, Andreas; Sato, Yoshiki

    2017-09-25

    In this paper we discuss geodesic Witten diagrams in generic holographic conformal field theories with boundary or defect. Boundary CFTs allow two different de-compositions of two-point functions into conformal blocks: boundary channel and ambient channel. Building on earlier work, we derive a holographic dual of the boundary channel decomposition in terms of bulk-to-bulk propagators on lower dimensional AdS slices. In the situation in which we can treat the boundary or defect as a perturbation around pure AdS spacetime, we obtain the leading corrections to the two-point function both in boundary and ambient channel in terms of geodesic Witten diagrams whichmore » exactly reproduce the decomposition into corresponding conformal blocks on the field theory side.« less

  9. Influence of grain boundaries on the distribution of components in binary alloys

    NASA Astrophysics Data System (ADS)

    L'vov, P. E.; Svetukhin, V. V.

    2017-12-01

    Based on the free-energy density functional method (the Cahn-Hilliard equation), a phenomenological model that describes the influence of grain boundaries on the distribution of components in binary alloys has been developed. The model is built on the assumption of the difference between the interaction parameters of solid solution components in the bulk and at the grain boundary. The difference scheme based on the spectral method is proposed to solve the Cahn-Hilliard equation with interaction parameters depending on coordinates. Depending on the ratio between the interaction parameters in the bulk and at the grain boundary, temperature, and alloy composition, the model can give rise to different types of distribution of a dissolved component, namely, either depletion or enrichment of the grain-boundary area, preferential grainboundary precipitation, competitive precipitation in the bulk and at the grain boundary, etc.

  10. Boundary-element modelling of dynamics in external poroviscoelastic problems

    NASA Astrophysics Data System (ADS)

    Igumnov, L. A.; Litvinchuk, S. Yu; Ipatov, A. A.; Petrov, A. N.

    2018-04-01

    A problem of a spherical cavity in porous media is considered. Porous media are assumed to be isotropic poroelastic or isotropic poroviscoelastic. The poroviscoelastic formulation is treated as a combination of Biot’s theory of poroelasticity and elastic-viscoelastic correspondence principle. Such viscoelastic models as Kelvin–Voigt, Standard linear solid, and a model with weakly singular kernel are considered. Boundary field study is employed with the help of the boundary element method. The direct approach is applied. The numerical scheme is based on the collocation method, regularized boundary integral equation, and Radau stepped scheme.

  11. 78 FR 68735 - Reduction or Suspension of Safe Harbor Contributions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-15

    ... forth in section 401(k)(3), called the actual deferral percentage (ADP) test, or one of the design-based... design-based safe harbor method under which a CODA is treated as satisfying the ADP test if the... the design-based alternatives in section 401(m)(10), 401(m)(11), or 401(m)(12). The ACP test in...

  12. Strategies for Countering Terrorist Safe Havens

    DTIC Science & Technology

    2014-02-20

    within safe havens, tactical containment, pseudo operations, and surrogate security forces. The thesis draws from four historical case studies to...leadership targeting within safe havens, tactical containment, pseudo operations, and surrogate security forces. The thesis draws from four historical case ...surrogate forces and pseudo operations—provide viable potential options for USSOF to counter the complex problem of safe havens. Overall, the case

  13. Boundary objects in complementary and alternative medicine: acupuncture vs. Christian Science.

    PubMed

    Owens, Kellie

    2015-03-01

    Nearly four in ten American use complementary or alternative medicine (CAM) each year. Even with a large number of patients, CAM practitioners face scrutiny from physicians and biomedical researchers who, in an era of evidence-based medicine, argue there is little evidence to support CAM treatments. Examining how CAM has or has not been integrated into American health care is crucial in understanding the contemporary boundaries of healthcare systems. An analytical tool from science and technology studies, boundary objects, can help scholars of medicine understand which practices become integrated into these systems. Using a comparative analysis based on archival and interview data, this paper examines the use of boundary objects in two alternative medical practices - acupuncture and Christian Science. While boundary objects alone cannot explain what health practices succeed or fail, juxtaposing the use of boundary objects by different CAM groups identifies the work boundary objects do to facilitate integration and the conditions under which they "work." I find that acupuncturists' use of sterile needles as a boundary objects assists in their effective integration into U.S. healthcare because needles are both a symbol of biomedical prowess and a potentially unsafe device requiring regulation. Christian Scientists' use of the placebo effect as a boundary object has not succeeded because they fail to acknowledge the different contextual definitions of the placebo effect in biomedical communities. This comparative analysis highlights how context affects which boundary objects "work" for CAM practices and theorizes why alternative health practices succeed or fail to become integrated into healthcare systems. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Is a structured, manualized, evidence-based treatment protocol culturally competent and equivalently effective among American Indian parents in child welfare?

    PubMed

    Chaffin, Mark; Bard, David; Bigfoot, Dolores Subia; Maher, Erin J

    2012-08-01

    In a statewide implementation, the manualized SafeCare home-based model was effective in reducing child welfare recidivism and producing high client satisfaction. Concerns about the effectiveness and acceptability of structured, manualized models with American Indians have been raised in the literature, but have rarely been directly tested. This study tests recidivism reduction equivalency and acceptability among American Indian parents. A subpopulation of 354 American Indian parents was drawn from a larger trial that compared services with versus without modules of the SafeCare model. Outcomes were 6-year recidivism, pre/post/follow-up measures of depression and child abuse potential, and posttreatment consumer ratings of working alliance, service satisfaction, and cultural competency. Recidivism reduction among American Indian parents was found to be equivalent for cases falling within customary SafeCare inclusion criteria. When extended to cases outside customary inclusion boundaries, there was no apparent recidivism advantage or disadvantage. Contrary to concerns, SafeCare had higher consumer ratings of cultural competency, working alliance, service quality, and service benefit. Findings support using SafeCare with American Indians parents who meet customary SafeCare inclusion criteria. Findings do not support concerns in the literature that a manualized, structured, evidence-based model might be less effective or culturally unacceptable for American Indians.

  15. Is a Structured, Manualized, Evidence-Based Treatment Protocol Culturally Competent and Equivalently Effective Among American Indian Parents in Child Welfare?

    PubMed Central

    Chaffin, Mark; Bard, David; Bigfoot, Dolores Subia; Maher, Erin J.

    2015-01-01

    In a statewide implementation, the manualized SafeCare home–based model was effective in reducing child welfare recidivism and producing high client satisfaction. Concerns about the effectiveness and acceptability of structured, manualized models with American Indians have been raised in the literature, but have rarely been directly tested. This study tests recidivism reduction equivalency and acceptability among American Indian parents. A subpopulation of 354 American Indian parents was drawn from a larger trial that compared services with versus without modules of the SafeCare model. Outcomes were 6-year recidivism, pre/post/follow-up measures of depression and child abuse potential, and posttreatment consumer ratings of working alliance, service satisfaction, and cultural competency. Recidivism reduction among American Indian parents was found to be equivalent for cases falling within customary SafeCare inclusion criteria. When extended to cases outside customary inclusion boundaries, there was no apparent recidivism advantage or disadvantage. Contrary to concerns, SafeCare had higher consumer ratings of cultural competency, working alliance, service quality, and service benefit. Findings support using SafeCare with American Indians parents who meet customary SafeCare inclusion criteria. Findings do not support concerns in the literature that a manualized, structured, evidence-based model might be less effective or culturally unacceptable for American Indians. PMID:22927674

  16. Recommendations for Safe Separation Distances from the Kennedy Space Center (KSC) Vehicle Assembly Building (VAB) Using a Heat-Flux-Based Analytical Approach (Abridged)

    NASA Technical Reports Server (NTRS)

    Cragg, Clinton H.; Bowman, Howard; Wilson, John E.

    2011-01-01

    The NASA Engineering and Safety Center (NESC) was requested to provide computational modeling to support the establishment of a safe separation distance surrounding the Kennedy Space Center (KSC) Vehicle Assembly Building (VAB). The two major objectives of the study were 1) establish a methodology based on thermal flux to determine safe separation distances from the Kennedy Space Center's (KSC's) Vehicle Assembly Building (VAB) with large numbers of solid propellant boosters containing hazard division 1.3 classification propellants, in case of inadvertent ignition; and 2) apply this methodology to the consideration of housing eight 5-segment solid propellant boosters in the VAB. The results of the study are contained in this report.

  17. On the Effects of Surface Roughness on Boundary Layer Transition

    NASA Technical Reports Server (NTRS)

    Choudhari, Meelan M.; Li, Fei; Chang, Chau-Lyan; Edwards, Jack

    2009-01-01

    Surface roughness can influence laminar-turbulent transition in many different ways. This paper outlines selected analyses performed at the NASA Langley Research Center, ranging in speed from subsonic to hypersonic Mach numbers and highlighting the beneficial as well as adverse roles of the surface roughness in technological applications. The first theme pertains to boundary-layer tripping on the forebody of a hypersonic airbreathing configuration via a spanwise periodic array of trip elements, with the goal of understanding the physical mechanisms underlying roughness-induced transition in a high-speed boundary layer. The effect of an isolated, finite amplitude roughness element on a supersonic boundary layer is considered next. The other set of flow configurations examined herein corresponds to roughness based laminar flow control in subsonic and supersonic swept wing boundary layers. A common theme to all of the above configurations is the need to apply higher fidelity, physics based techniques to develop reliable predictions of roughness effects on laminar-turbulent transition.

  18. A Discrete Analysis of Non-reflecting Boundary Conditions for Discontinuous Galerkin Method

    NASA Technical Reports Server (NTRS)

    Hu, Fang Q.; Atkins, Harold L.

    2003-01-01

    We present a discrete analysis of non-reflecting boundary conditions for the discontinuous Galerkin method. The boundary conditions considered in this paper include the recently proposed Perfectly Matched Layer absorbing boundary condition for the linearized Euler equation and two non-reflecting boundary conditions based on the characteristic decomposition of the flux on the boundary. The analyses for the three boundary conditions are carried out in a unifled way. In each case, eigensolutions of the discrete system are obtained and applied to compute the numerical reflection coefficients of a specified out-going wave. The dependencies of the reflections at the boundary on the out-going wave angle and frequency as well as the mesh sizes arc? studied. Comparisons with direct numerical simulation results are also presented.

  19. Three-dimensional piezoelectric boundary elements

    NASA Astrophysics Data System (ADS)

    Hill, Lisa Renee

    The strong coupling between mechanical and electrical fields in piezoelectric ceramics makes them appropriate for use as actuation devices; as a result, they are an important part of the emerging technologies of smart materials and structures. These piezoceramics are very brittle and susceptible to fracture, especially under the severe loading conditions which may occur in service. A significant portion of the applications under investigation involve dynamic loading conditions. Once a crack is initiated in the piezoelectric medium, the mechanical and electrical fields can act to drive the crack growth. Failure of the actuator can result from a catastrophic fracture event or from the cumulative effects of cyclic fatigue. The presence of these cracks, or other types of material defects, alter the mechanical and electrical fields inside the body. Specifically, concentrations of stress and electric field are present near a flaw and can lead to material yielding or localized depoling, which in turn can affect the sensor/actuator performance or cause failure. Understanding these effects is critical to the success of these smart structures. The complex coupling behavior and the anisotropy of the material makes the use of numerical methods necessary for all but the simplest problems. To this end, a three-dimensional boundary element method program is developed to evaluate the effect of flaws on these piezoelectric materials. The program is based on the linear governing equations of piezoelectricity and relies on a numerically evaluated Green's function for solution. The boundary element method was selected as the evaluation tool due to its ability to model the interior domain exactly. Thus, for piezoelectric materials the coupling between mechanical and electrical fields is not approximated inside the body. Holes in infinite and finite piezoceramics are investigated, with the localized stresses and electric fields clearly developed. The accuracy of the piezoelectric

  20. Boundary layer effects on liners for aircraft engines

    NASA Astrophysics Data System (ADS)

    Gabard, Gwénaël

    2016-10-01

    The performance of acoustic treatments installed on aircraft engines is strongly influenced by the boundary layer of the grazing flow on the surface of the liner. The parametric study presented in this paper illustrates the extent of this effect and identifies when it is significant. The acoustic modes of a circular duct with flow are calculated using a finite difference method. The parameters are representative of the flow conditions, liners and sound fields found in current turbofan engines. Both the intake and bypass ducts are considered. Results show that there is a complex interplay between the boundary layer thickness, the direction of propagation and the liner impedance and that the boundary layer can have a strong impact on liner performance for typical configurations (including changes of the order of 30 dB on the attenuation of modes associated with tonal fan noise). A modified impedance condition including the effect of a small but finite boundary layer thickness is considered and compared to the standard Myers condition based on an infinitely thin boundary layer. We show how this impedance condition can be implemented in a mode calculation method by introducing auxiliary variables. This condition is able to capture the trends associated with the boundary layer effects and in most cases provides improved predictions of liner performance.

  1. Numerical Boundary Conditions for Computational Aeroacoustics Benchmark Problems

    NASA Technical Reports Server (NTRS)

    Tam, Chritsopher K. W.; Kurbatskii, Konstantin A.; Fang, Jun

    1997-01-01

    Category 1, Problems 1 and 2, Category 2, Problem 2, and Category 3, Problem 2 are solved computationally using the Dispersion-Relation-Preserving (DRP) scheme. All these problems are governed by the linearized Euler equations. The resolution requirements of the DRP scheme for maintaining low numerical dispersion and dissipation as well as accurate wave speeds in solving the linearized Euler equations are now well understood. As long as 8 or more mesh points per wavelength is employed in the numerical computation, high quality results are assured. For the first three categories of benchmark problems, therefore, the real challenge is to develop high quality numerical boundary conditions. For Category 1, Problems 1 and 2, it is the curved wall boundary conditions. For Category 2, Problem 2, it is the internal radiation boundary conditions inside the duct. For Category 3, Problem 2, they are the inflow and outflow boundary conditions upstream and downstream of the blade row. These are the foci of the present investigation. Special nonhomogeneous radiation boundary conditions that generate the incoming disturbances and at the same time allow the outgoing reflected or scattered acoustic disturbances to leave the computation domain without significant reflection are developed. Numerical results based on these boundary conditions are provided.

  2. Using Molecular Genetic Markers to Resolve a Subspecies Boundary: The Northern Boundary of the Southwestern Willow Flycatcher in the Four-Corner States

    USGS Publications Warehouse

    Paxton, Eben H.; Sogge, Mark K.; Theimer, Tad C.; Girard, Jessica; Keim, Paul

    2008-01-01

    , but should be more biologically meaningful because it incorporates the landscape features that may be driving separation of the subspecies. Even so, we caution that using any narrow boundary line as an indicator of subspecies identity could be misleading because biologically the boundary is a region of intergradation rather than a discrete line. Designating, a boundary ultimately becomes a regulatory and management decision based on how much of the genetic variation unique to a subspecies should be protected. We discuss how the results of this study can help guide this decision process by wildlife policy makers.

  3. Making Boundaries Great Again: Essentialism and Support for Boundary-Enhancing Initiatives.

    PubMed

    Roberts, Steven O; Ho, Arnold K; Rhodes, Marjorie; Gelman, Susan A

    2017-12-01

    Psychological essentialism entails a focus on category boundaries (e.g., categorizing people as men or women) and an increase in the conceptual distance between those boundaries (e.g., accentuating the differences between men and women). Across eight studies, we demonstrate that essentialism additionally entails an increase in support for boundary-enhancing legislation, policies, and social services, and that it does so under conditions that disadvantage social groups, as well as conditions that benefit them. First, individual differences in essentialism were associated with support for legislation mandating that transgender people use restrooms corresponding with their biological sex, and with support for the boundary-enhancing policies of the 2016 then-presumptive Republican presidential nominee (i.e., Donald Trump). Second, essentialism was associated with support for same-gender classrooms designed to promote student learning, as well as support for services designed to benefit LGBTQ (lesbian, gay, bisexual, transgender, queer) individuals. These findings demonstrate the boundary-enhancing implications of essentialism and their social significance.

  4. Psychodynamic Perspective on Therapeutic Boundaries

    PubMed Central

    Bridges, Nancy A.

    1999-01-01

    Discussion of boundaries in therapeutic work most often focuses on boundary maintenance, risk management factors, and boundary violations. The psychodynamic meaning and clinical management of boundaries in therapeutic relationships remains a neglected area of discourse. Clinical vignettes will illustrate a psychodynamic, developmental-relational perspective using boundary dilemmas to deepen and advance the therapeutic process. This article contributes to the dialogue about the process of making meaning and constructing therapeutically useful and creative boundaries that further the psychotherapeutic process. PMID:10523432

  5. Progressive wave expansions and open boundary problems

    NASA Technical Reports Server (NTRS)

    Hagstrom, T.; Hariharan, S. I.

    1995-01-01

    In this paper we construct progressive wave expansions and asymptotic boundary conditions for wave-like equations in exterior domains, including applications to electromagnetics, compressible flows and aero-acoustics. The development of the conditions will be discussed in two parts. The first part will include derivations of asymptotic conditions based on the well-known progressive wave expansions for the two-dimensional wave equations. A key feature in the derivations is that the resulting family of boundary conditions involves a single derivative in the direction normal to the open boundary. These conditions are easy to implement and an application in electromagnetics will be presented. The second part of the paper will discuss the theory for hyperbolic systems in two dimensions. Here, the focus will be to obtain the expansions in a general way and to use them to derive a class of boundary conditions that involve only time derivatives or time and tangential derivatives. Maxwell's equations and the compressible Euler equations are used as examples. Simulations with the linearized Euler equations are presented to validate the theory.

  6. The Boundary Function Method. Fundamentals

    NASA Astrophysics Data System (ADS)

    Kot, V. A.

    2017-03-01

    The boundary function method is proposed for solving applied problems of mathematical physics in the region defined by a partial differential equation of the general form involving constant or variable coefficients with a Dirichlet, Neumann, or Robin boundary condition. In this method, the desired function is defined by a power polynomial, and a boundary function represented in the form of the desired function or its derivative at one of the boundary points is introduced. Different sequences of boundary equations have been set up with the use of differential operators. Systems of linear algebraic equations constructed on the basis of these sequences allow one to determine the coefficients of a power polynomial. Constitutive equations have been derived for initial boundary-value problems of all the main types. With these equations, an initial boundary-value problem is transformed into the Cauchy problem for the boundary function. The determination of the boundary function by its derivative with respect to the time coordinate completes the solution of the problem.

  7. Interferometric data for a shock-wave/boundary-layer interaction

    NASA Technical Reports Server (NTRS)

    Dunagan, Stephen E.; Brown, James L.; Miles, John B.

    1986-01-01

    An experimental study of the axisymmetric shock-wave / boundary-layer strong interaction flow generated in the vicinity of a cylinder-cone intersection was conducted. The study data are useful in the documentation and understanding of compressible turbulent strong interaction flows, and are part of a more general effort to improve turbulence modeling for compressible two- and three-dimensional strong viscous/inviscid interactions. The nominal free stream Mach number was 2.85. Tunnel total pressures of 1.7 and 3.4 atm provided Reynolds number values of 18 x 10(6) and 36 x 10(6) based on model length. Three cone angles were studied giving negligible, incipient, and large scale flow separation. The initial cylinder boundary layer upstream of the interaction had a thickness of 1.0 cm. The subsonic layer of the cylinder boundary layer was quite thin, and in all cases, the shock wave penetrated a significant portion of the boundary layer. Owing to the thickness of the cylinder boundary layer, considerable structural detail was resolved for the three shock-wave / boundary-layer interaction cases considered. The primary emphasis was on the application of the holographic interferometry technique. The density field was deduced from an interferometric analysis based on the Able transform. Supporting data were obtained using a 2-D laser velocimeter, as well as mean wall pressure and oil flow measurements. The attached flow case was observed to be steady, while the separated cases exhibited shock unsteadiness. Comparisons with Navier-Stokes computations using a two-equation turbulence model are presented.

  8. Safe biodegradable fluorescent particles

    DOEpatents

    Martin, Sue I [Berkeley, CA; Fergenson, David P [Alamo, CA; Srivastava, Abneesh [Santa Clara, CA; Bogan, Michael J [Dublin, CA; Riot, Vincent J [Oakland, CA; Frank, Matthias [Oakland, CA

    2010-08-24

    A human-safe fluorescence particle that can be used for fluorescence detection instruments or act as a safe simulant for mimicking the fluorescence properties of microorganisms. The particle comprises a non-biological carrier and natural fluorophores encapsulated in the non-biological carrier. By doping biodegradable-polymer drug delivery microspheres with natural or synthetic fluorophores, the desired fluorescence can be attained or biological organisms can be simulated without the associated risks and logistical difficulties of live microorganisms.

  9. Numerical Boundary Condition Procedures

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Topics include numerical procedures for treating inflow and outflow boundaries, steady and unsteady discontinuous surfaces, far field boundaries, and multiblock grids. In addition, the effects of numerical boundary approximations on stability, accuracy, and convergence rate of the numerical solution are discussed.

  10. Safe Haven.

    ERIC Educational Resources Information Center

    Bush, Gail

    2003-01-01

    Discusses school libraries as safe havens for teenagers and considers elements that foster that atmosphere, including the physical environment, lack of judgments, familiarity, leisure, and a welcoming nature. Focuses on the importance of relationships, and taking the time to listen to teens and encourage them. (LRW)

  11. Boundary layers in cataclysmic variables: The HEAO-1 X-ray constraints

    NASA Technical Reports Server (NTRS)

    Jensen, K. A.

    1983-01-01

    The predictions of the boundary layer model for the X-ray emission from novae are summarized. A discrepancy between observations and theory in the X-ray observations is found. Constraints on the nature of the boundary layers in novae, based on the lack of detections of novae in the HEAO-1 soft X-ray survey are provided. Temperature and column densities for optically thick boundary layers in novae are estimated.

  12. A pseudospectra-based approach to non-normal stability of embedded boundary methods

    NASA Astrophysics Data System (ADS)

    Rapaka, Narsimha; Samtaney, Ravi

    2017-11-01

    We present non-normal linear stability of embedded boundary (EB) methods employing pseudospectra and resolvent norms. Stability of the discrete linear wave equation is characterized in terms of the normalized distance of the EB to the nearest ghost node (α) in one and two dimensions. An important objective is that the CFL condition based on the Cartesian grid spacing remains unaffected by the EB. We consider various discretization methods including both central and upwind-biased schemes. Stability is guaranteed when α <=αmax ranges between 0.5 and 0.77 depending on the discretization scheme. Also, the stability characteristics remain the same in both one and two dimensions. Sharper limits on the sufficient conditions for stability are obtained based on the pseudospectral radius (the Kreiss constant) than the restrictive limits based on the usual singular value decomposition analysis. We present a simple and robust reclassification scheme for the ghost cells (``hybrid ghost cells'') to ensure Lax stability of the discrete systems. This has been tested successfully for both low and high order discretization schemes with transient growth of at most O (1). Moreover, we present a stable, fourth order EB reconstruction scheme. Supported by the KAUST Office of Competitive Research Funds under Award No. URF/1/1394-01.

  13. FoodWiki: Ontology-Driven Mobile Safe Food Consumption System.

    PubMed

    Çelik, Duygu

    2015-01-01

    An ontology-driven safe food consumption mobile system is considered. Over 3,000 compounds are being added to processed food, with numerous effects on the food: to add color, stabilize, texturize, preserve, sweeten, thicken, add flavor, soften, emulsify, and so forth. According to World Health Organization, governments have lately focused on legislation to reduce such ingredients or compounds in manufactured foods as they may have side effects causing health risks such as heart disease, cancer, diabetes, allergens, and obesity. By supervising what and how much to eat as well as what not to eat, we can maximize a patient's life quality through avoidance of unhealthy ingredients. Smart e-health systems with powerful knowledge bases can provide suggestions of appropriate foods to individuals. Next-generation smart knowledgebase systems will not only include traditional syntactic-based search, which limits the utility of the search results, but will also provide semantics for rich searching. In this paper, performance of concept matching of food ingredients is semantic-based, meaning that it runs its own semantic based rule set to infer meaningful results through the proposed Ontology-Driven Mobile Safe Food Consumption System (FoodWiki).

  14. FoodWiki: Ontology-Driven Mobile Safe Food Consumption System

    PubMed Central

    Çelik, Duygu

    2015-01-01

    An ontology-driven safe food consumption mobile system is considered. Over 3,000 compounds are being added to processed food, with numerous effects on the food: to add color, stabilize, texturize, preserve, sweeten, thicken, add flavor, soften, emulsify, and so forth. According to World Health Organization, governments have lately focused on legislation to reduce such ingredients or compounds in manufactured foods as they may have side effects causing health risks such as heart disease, cancer, diabetes, allergens, and obesity. By supervising what and how much to eat as well as what not to eat, we can maximize a patient's life quality through avoidance of unhealthy ingredients. Smart e-health systems with powerful knowledge bases can provide suggestions of appropriate foods to individuals. Next-generation smart knowledgebase systems will not only include traditional syntactic-based search, which limits the utility of the search results, but will also provide semantics for rich searching. In this paper, performance of concept matching of food ingredients is semantic-based, meaning that it runs its own semantic based rule set to infer meaningful results through the proposed Ontology-Driven Mobile Safe Food Consumption System (FoodWiki). PMID:26221624

  15. The limits of boundaries: unpacking localization and cognitive mapping relative to a boundary.

    PubMed

    Zhou, Ruojing; Mou, Weimin

    2018-05-01

    Previous research (Zhou, Mou, Journal of Experimental Psychology: Learning, Memory and Cognition 42(8):1316-1323, 2016) showed that learning individual locations relative to a single landmark, compared to learning relative to a boundary, led to more accurate inferences of inter-object spatial relations (cognitive mapping of multiple locations). Following our past findings, the current study investigated whether the larger number of reference points provided by a homogeneous circular boundary, as well as less accessible knowledge of direct spatial relations among the multiple reference points, would lead to less effective cognitive mapping relative to the boundary. Accordingly, we manipulated (a) the number of primary reference points (one segment drawn from a circular boundary, four such segments, vs. the complete boundary) available when participants were localizing four objects sequentially (Experiment 1) and (b) the extendedness of each of the four segments (Experiment 2). The results showed that cognitive mapping was the least accurate in the whole boundary condition. However, expanding each of the four segments did not affect the accuracy of cognitive mapping until the four were connected to form a continuous boundary. These findings indicate that when encoding locations relative to a homogeneous boundary, participants segmented the boundary into differentiated pieces and subsequently chose the most informative local part (i.e., the segment closest in distance to one location) as the primary reference point for a particular location. During this process, direct spatial relations among the reference points were likely not attended to. These findings suggest that people might encode and represent bounded space in a fragmented fashion when localizing within a homogeneous boundary.

  16. Smoothed Particle Hydrodynamics Continuous Boundary Force method for Navier-Stokes equations subject to Robin boundary condition

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

    Pan, Wenxiao; Bao, Jie; Tartakovsky, Alexandre M.

    2014-02-15

    Robin boundary condition for the Navier-Stokes equations is used to model slip conditions at the fluid-solid boundaries. A novel Continuous Boundary Force (CBF) method is proposed for solving the Navier-Stokes equations subject to Robin boundary condition. In the CBF method, the Robin boundary condition at boundary is replaced by the homogeneous Neumann boundary condition at the boundary and a volumetric force term added to the momentum conservation equation. Smoothed Particle Hydrodynamics (SPH) method is used to solve the resulting Navier-Stokes equations. We present solutions for two-dimensional and three-dimensional flows in domains bounded by flat and curved boundaries subject to variousmore » forms of the Robin boundary condition. The numerical accuracy and convergence are examined through comparison of the SPH-CBF results with the solutions of finite difference or finite element method. Taken the no-slip boundary condition as a special case of slip boundary condition, we demonstrate that the SPH-CBF method describes accurately both no-slip and slip conditions.« less

  17. International boundary experiences by the United Nations

    NASA Astrophysics Data System (ADS)

    Kagawa, A.

    2013-12-01

    of geospatial solutions, some of the good practices that have been applied in preceding projects, but there have been challenges and limitations faced. However, these challenges need to be seen as an opportunity to improve the geospatial technology solutions in future international boundary projects. This presentation will also share the aspirations that the United Nations Cartographic Section has in becoming a facilitator in geospatial technical aspects related to international boundary issues as we increasingly develop our geospatial institutional knowledge base and expertise. The presentation will conclude by emphasizing the need for more collaboration between different actors dealing with geospatial technology on borderland issues in order to meet the main goal of the United Nations - to live and work together as "We the Peoples of the United Nations".

  18. Why don't humanitarian organizations provide safe abortion services?

    PubMed

    McGinn, Therese; Casey, Sara E

    2016-01-01

    Although sexual and reproductive health services have become more available in humanitarian settings over the last decade, safe abortion services are still rarely provided. The authors' observations suggest that four reasons are typically given for this gap: 'There's no need'; 'Abortion is too complicated to provide in crises'; 'Donors don't fund abortion services'; and 'Abortion is illegal'. However, each of these reasons is based on false premises. Unsafe abortion is a major cause of maternal mortality globally, and the collapse of health systems in crises suggests it likely increases in humanitarian settings. Abortion procedures can be safely performed in health centers by mid-level providers without sophisticated equipment or supplies. Although US government aid does not fund abortion-related activities, other donors, including many European governments, do fund abortion services. In most countries, covering 99 % of the world's population, abortion is permitted under some circumstances; it is illegal without exception in only six countries. International law supports improved access to safe abortion. As none of the reasons often cited for not providing these services is valid, it is the responsibility of humanitarian NGOs to decide where they stand regarding their commitment to humanitarian standards and women's right to high quality and non-discriminatory health services. Providing safe abortion to women who become pregnant as a result of rape in war may be a more comfortable place for organizations to begin the discussion. Making safe abortion available will improve women's health and human rights and save lives.

  19. Substorm injection boundaries. [magnetospheric electric field model

    NASA Technical Reports Server (NTRS)

    Mcilwain, C. E.

    1974-01-01

    An improved magnetospheric electric field model is used to compute the initial locations of particles injected by several substorms. Trajectories are traced from the time of their encounter with the ATS-5 satellite backwards to the onset time given by ground-based magnetometers. A spiral shaped inner boundary of injection is found which is quite similar to that found by a statistical analysis. This injection boundary is shown to move in an energy dependent fashion which can explain the soft energy spectra observed at the inner edge of the electrons plasma sheet.

  20. More than a Safe Space

    ERIC Educational Resources Information Center

    Sadowski, Michael

    2016-01-01

    Over the past three decades, much of the conversation about LGBTQ students in schools has centered on safety--anti-bullying policies, the "safe space" of gay-straight alliances, and "safe zones" marked by rainbow-colored stickers on classroom doors. In this article, Michael Sadowski argues that it's time to move beyond safety…

  1. Video shot boundary detection using region-growing-based watershed method

    NASA Astrophysics Data System (ADS)

    Wang, Jinsong; Patel, Nilesh; Grosky, William

    2004-10-01

    In this paper, a novel shot boundary detection approach is presented, based on the popular region growing segmentation method - Watershed segmentation. In image processing, gray-scale pictures could be considered as topographic reliefs, in which the numerical value of each pixel of a given image represents the elevation at that point. Watershed method segments images by filling up basins with water starting at local minima, and at points where water coming from different basins meet, dams are built. In our method, each frame in the video sequences is first transformed from the feature space into the topographic space based on a density function. Low-level features are extracted from frame to frame. Each frame is then treated as a point in the feature space. The density of each point is defined as the sum of the influence functions of all neighboring data points. The height function that is originally used in Watershed segmentation is then replaced by inverting the density at the point. Thus, all the highest density values are transformed into local minima. Subsequently, Watershed segmentation is performed in the topographic space. The intuitive idea under our method is that frames within a shot are highly agglomerative in the feature space and have higher possibilities to be merged together, while those frames between shots representing the shot changes are not, hence they have less density values and are less likely to be clustered by carefully extracting the markers and choosing the stopping criterion.

  2. Sound propagation in street canyons: comparison between diffusely and geometrically reflecting boundaries

    PubMed

    Kang

    2000-03-01

    This paper systematically compares the sound fields in street canyons with diffusely and geometrically reflecting boundaries. For diffuse boundaries, a radiosity-based theoretical/computer model has been developed. For geometrical boundaries, the image source method has been used. Computations using the models show that there are considerable differences between the sound fields resulting from the two kinds of boundaries. By replacing diffuse boundaries with geometrical boundaries, the sound attenuation along the length becomes significantly less; the RT30 is considerably longer; and the extra attenuation caused by air or vegetation absorption is reduced. There are also some similarities between the sound fields under the two boundary conditions. For example, in both cases the sound attenuation along the length with a given amount of absorption is the highest if the absorbers are arranged on one boundary and the lowest if they are evenly distributed on all boundaries. Overall, the results suggest that, from the viewpoint of urban noise reduction, it is better to design the street boundaries as diffusely reflective rather than acoustically smooth.

  3. Impact of internal crystalline boundaries on lattice thermal conductivity: Importance of boundary structure and spacing

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

    Aghababaei, Ramin, E-mail: ramin.aghababaei@epfl.ch; Anciaux, Guillaume; Molinari, Jean-François

    2014-11-10

    The low thermal conductivity of nano-crystalline materials is commonly explained via diffusive scattering of phonons by internal boundaries. In this study, we have quantitatively studied phonon-crystalline boundaries scattering and its effect on the overall lattice thermal conductivity of crystalline bodies. Various types of crystalline boundaries such as stacking faults, twins, and grain boundaries have been considered in FCC crystalline structures. Accordingly, the specularity coefficient has been determined for different boundaries as the probability of the specular scattering across boundaries. Our results show that in the presence of internal boundaries, the lattice thermal conductivity can be characterized by two parameters: (1)more » boundary spacing and (2) boundary excess free volume. We show that the inverse of the lattice thermal conductivity depends linearly on a non-dimensional quantity which is the ratio of boundary excess free volume over boundary spacing. This shows that phonon scattering across crystalline boundaries is mainly a geometrically favorable process rather than an energetic one. Using the kinetic theory of phonon transport, we present a simple analytical model which can be used to evaluate the lattice thermal conductivity of nano-crystalline materials where the ratio can be considered as an average density of excess free volume. While this study is focused on FCC crystalline materials, where inter-atomic potentials and corresponding defect structures have been well studied in the past, the results would be quantitatively applicable for semiconductors in which heat transport is mainly due to phonon transport.« less

  4. Evolution of the Hubble Space Telescope Safing Systems

    NASA Technical Reports Server (NTRS)

    Pepe, Joyce; Myslinski, Michael

    2006-01-01

    The Hubble Space Telescope (HST) was launched on April 24 1990, with an expected lifespan of 15 years. Central to the spacecraft design was the concept of a series of on-orbit shuttle servicing missions permitting astronauts to replace failed equipment, update the scientific instruments and keep the HST at the forefront of astronomical discoveries. One key to the success of the Hubble mission has been the robust Safing systems designed to monitor the performance of the observatory and to react to keep the spacecraft safe in the event of equipment anomaly. The spacecraft Safing System consists of a range of software tests in the primary flight computer that evaluate the performance of mission critical hardware, safe modes that are activated when the primary control mode is deemed inadequate for protecting the vehicle, and special actions that the computer can take to autonomously reconfigure critical hardware. The HST Safing System was structured to autonomously detect electrical power system, data management system, and pointing control system malfunctions and to configure the vehicle to ensure safe operation without ground intervention for up to 72 hours. There is also a dedicated safe mode computer that constantly monitors a keep-alive signal from the primary computer. If this signal stops, the safe mode computer shuts down the primary computer and takes over control of the vehicle, putting it into a safe, low-power configuration. The HST Safing system has continued to evolve as equipment has aged, as new hardware has been installed on the vehicle, and as the operation modes have matured during the mission. Along with the continual refinement of the limits used in the safing tests, several new tests have been added to the monitoring system, and new safe modes have been added to the flight software. This paper will focus on the evolution of the HST Safing System and Safing tests, and the importance of this evolution to prolonging the science operations of the

  5. Anatomical Basis for Safe and Effective Volumization of the Temple.

    PubMed

    Breithaupt, Andrew D; Jones, Derek H; Braz, Andre; Narins, Rhoda; Weinkle, Susan

    2015-12-01

    One of the earliest but often unaddressed signs of facial aging is volume loss in the temple. Treatment of the area can produce satisfying results for both patient and practitioner. Safe injection requires explicit knowledge of the anatomy to avoid complications related to the multitude of vessels that course throughout the region at various depths. The authors aim to detail the anatomy of the area and provide a safe and easy-to-follow method for injection. The authors review the relevant anatomy of the temporal region and its application to cosmetic filler injections. The authors describe an easy-to-follow approach for a safe and effective injection window based on numerous anatomical studies. Injection in this area is not without risk, including potential blindness. The authors review the potential complications and their treatments. Hollowing of the temple is an early sign of aging that, when corrected, can lead to significant patient and practitioner satisfaction. Proper anatomically knowledge is required to avoid potentially severe complications. In this study, the authors present a reliable technique to safely and effectively augment this often undertreated area of the aging face.

  6. Exponential Boundary Observers for Pressurized Water Pipe

    NASA Astrophysics Data System (ADS)

    Hermine Som, Idellette Judith; Cocquempot, Vincent; Aitouche, Abdel

    2015-11-01

    This paper deals with state estimation on a pressurized water pipe modeled by nonlinear coupled distributed hyperbolic equations for non-conservative laws with three known boundary measures. Our objective is to estimate the fourth boundary variable, which will be useful for leakage detection. Two approaches are studied. Firstly, the distributed hyperbolic equations are discretized through a finite-difference scheme. By using the Lipschitz property of the nonlinear term and a Lyapunov function, the exponential stability of the estimation error is proven by solving Linear Matrix Inequalities (LMIs). Secondly, the distributed hyperbolic system is preserved for state estimation. After state transformations, a Luenberger-like PDE boundary observer based on backstepping mathematical tools is proposed. An exponential Lyapunov function is used to prove the stability of the resulted estimation error. The performance of the two observers are shown on a water pipe prototype simulated example.

  7. Managing Cassini Safe Mode Attitude at Saturn

    NASA Technical Reports Server (NTRS)

    Burk, Thomas A.

    2010-01-01

    The Cassini spacecraft was launched on October 15, 1997 and arrived at Saturn on June 30, 2004. It has performed detailed observations and remote sensing of Saturn, its rings, and its satellites since that time. In the event safe mode interrupts normal orbital operations, Cassini has flight software fault protection algorithms to detect, isolate, and recover to a thermally safe and commandable attitude and then wait for further instructions from the ground. But the Saturn environment is complex, and safety hazards change depending on where Cassini is in its orbital trajectory around Saturn. Selecting an appropriate safe mode attitude that insures safe operation in the Saturn environment, including keeping the star tracker field of view clear of bright bodies, while maintaining a quiescent, commandable attitude, is a significant challenge. This paper discusses the Cassini safe table management strategy and the key criteria that must be considered, especially during low altitude flybys of Titan, in deciding what spacecraft attitude should be used in the event of safe mode.

  8. Enhancement of perfluoropolyether boundary lubrication performance: I. Preliminary results

    NASA Technical Reports Server (NTRS)

    Jones, W. R., Jr.; Ajayi, O. O.; Goodell, A. J.; Wedeven, L. D.; Devine, E.; Premore, R. E.

    1995-01-01

    A ball bearing simulator operating under starved conditions was used to evaluate the boundary lubrication performance of a perfluoropolyether (PFPE) Krytox 143 AB. Several approaches to enhance boundary lubrication were studied. These included: (1) soluble boundary additives, (2) bearing surface modifications, (3) 'run-in' surface films, and (4) ceramic bearing components. In addition, results were compared with two non-perfluorinated liquid lubricant formulations. Based on these preliminary tests, the following tentative conclusions can be made: (1) substantial improvements in boundary lubrication performance were observed with a beta-diketone boundary additive and a tricresyl phosphate (TCP) liquid surface pretreatment; (2) the use of rough Si3N4 balls (Ra = 40 micro-in) also provided substantial improvement but with concomitant abrasive wear; (3) marginal improvements were seen with two boundary additives (a phosphine and a phosphatriazine) and a neat (100%) fluid (a carboxylic acid terminated PFPE); and surface pretreatments with a synthetic hydrocarbon, a PTFE coating, and TiC coated 440C and smooth Si3N4 balls (R(sub a) less than 1 micro-in); and (4) two non-PFPE lubricant formulations (a PAO and a synthetic hydrocarbon) yielded substantial improvements.

  9. Impact of lateral boundary conditions on regional analyses

    NASA Astrophysics Data System (ADS)

    Chikhar, Kamel; Gauthier, Pierre

    2017-04-01

    Regional and global climate models are usually validated by comparison to derived observations or reanalyses. Using a model in data assimilation results in a direct comparison to observations to produce its own analyses that may reveal systematic errors. In this study, regional analyses over North America are produced based on the fifth-generation Canadian Regional Climate Model (CRCM5) combined with the variational data assimilation system of the Meteorological Service of Canada (MSC). CRCM5 is driven at its boundaries by global analyses from ERA-interim or produced with the global configuration of the CRCM5. Assimilation cycles for the months of January and July 2011 revealed systematic errors in winter through large values in the mean analysis increments. This bias is attributed to the coupling of the lateral boundary conditions of the regional model with the driving data particularly over the northern boundary where a rapidly changing large scale circulation created significant cross-boundary flows. Increasing the time frequency of the lateral driving and applying a large-scale spectral nudging improved significantly the circulation through the lateral boundaries which translated in a much better agreement with observations.

  10. Viscoelastic deformation near active plate boundaries

    NASA Technical Reports Server (NTRS)

    Ward, S. N.

    1986-01-01

    Model deformations near the active plate boundaries of Western North America using space-based geodetic measurements as constraints are discussed. The first six months of this project were spent gaining familarity with space-based measurements, accessing the Crustal Dynamics Data Information Computer, and building time independent deformation models. The initial goal was to see how well the simplest elastic models can reproduce very long base interferometry (VLBI) baseline data. From the Crustal Dynamics Data Information Service, a total of 18 VLBI baselines are available which have been surveyed on four or more occasions. These data were fed into weighted and unweighted inversions to obtain baseline closure rates. Four of the better quality lines are illustrated. The deformation model assumes that the observed baseline rates result from a combination of rigid plate tectonic motions plus a component resulting from elastic strain build up due to a failure of the plate boundary to slip at the full plate tectonic rate. The elastic deformation resulting from the locked plate boundary is meant to portray interseismic strain accumulation. During and shortly after a large interplate earthquake, these strains are largely released, and points near the fault which were previously retarded suddenly catch up to the positions predicted by rigid plate models. Researchers judge the quality of fit by the sum squares of weighted residuals, termed total variance. The observed baseline closures have a total variance of 99 (cm/y)squared. When the RM2 velocities are assumed to model the data, the total variance increases to 154 (cm/y)squared.

  11. Switching moving boundary models for two-phase flow evaporators and condensers

    NASA Astrophysics Data System (ADS)

    Bonilla, Javier; Dormido, Sebastián; Cellier, François E.

    2015-03-01

    The moving boundary method is an appealing approach for the design, testing and validation of advanced control schemes for evaporators and condensers. When it comes to advanced control strategies, not only accurate but fast dynamic models are required. Moving boundary models are fast low-order dynamic models, and they can describe the dynamic behavior with high accuracy. This paper presents a mathematical formulation based on physical principles for two-phase flow moving boundary evaporator and condenser models which support dynamic switching between all possible flow configurations. The models were implemented in a library using the equation-based object-oriented Modelica language. Several integrity tests in steady-state and transient predictions together with stability tests verified the models. Experimental data from a direct steam generation parabolic-trough solar thermal power plant is used to validate and compare the developed moving boundary models against finite volume models.

  12. "Safe Schools within Safe Communities: A Regional Summit in the Heartland." Policy Briefs Special Report.

    ERIC Educational Resources Information Center

    Huertas, Aurelio, Jr.; Sullivan, Carol

    This report documents the proceedings of a regional policy seminar hosted by the Iowa Department of Education with support from the North Central Regional Educational Laboratory (NCREL) and the Midwest Regional Center for Drug-Free Schools and Communities (MRC). The seminar, "Safe Schools Within Safe Communities," was held on September 19-20,…

  13. From fields to objects: A review of geographic boundary analysis

    NASA Astrophysics Data System (ADS)

    Jacquez, G. M.; Maruca, S.; Fortin, M.-J.

    Geographic boundary analysis is a relatively new approach unfamiliar to many spatial analysts. It is best viewed as a technique for defining objects - geographic boundaries - on spatial fields, and for evaluating the statistical significance of characteristics of those boundary objects. This is accomplished using null spatial models representative of the spatial processes expected in the absence of boundary-generating phenomena. Close ties to the object-field dialectic eminently suit boundary analysis to GIS data. The majority of existing spatial methods are field-based in that they describe, estimate, or predict how attributes (variables defining the field) vary through geographic space. Such methods are appropriate for field representations but not object representations. As the object-field paradigm gains currency in geographic information science, appropriate techniques for the statistical analysis of objects are required. The methods reviewed in this paper are a promising foundation. Geographic boundary analysis is clearly a valuable addition to the spatial statistical toolbox. This paper presents the philosophy of, and motivations for geographic boundary analysis. It defines commonly used statistics for quantifying boundaries and their characteristics, as well as simulation procedures for evaluating their significance. We review applications of these techniques, with the objective of making this promising approach accessible to the GIS-spatial analysis community. We also describe the implementation of these methods within geographic boundary analysis software: GEM.

  14. Liver tumor boundaries identified intraoperatively using real-time indocyanine green fluorescence imaging.

    PubMed

    Zhang, Ya-Min; Shi, Rui; Hou, Jian-Cun; Liu, Zi-Rong; Cui, Zi-Lin; Li, Yang; Wu, Di; Shi, Yuan; Shen, Zhong-Yang

    2017-01-01

    Clear delineation between tumors and normal tissues is ideal for real-time surgical navigation imaging. We investigated applying indocyanine green (ICG) fluorescence imaging navigation using an intraoperative administration method in liver resection. Fifty patients who underwent liver resection were divided into two groups based on clinical situation and operative purpose. In group I, sizes of superficial liver tumors were determined; tiny tumors were identified. In group II, the liver resection margin was determined; real-time navigation was performed. ICG was injected intravenously at the beginning of the operation; the liver surface was observed with a photodynamic eye (PDE). Liver resection margins were determined using PDE. Fluorescence contrast between normal liver and tumor tissues was obvious in 32 of 35 patients. A boundary for half the liver or specific liver segments was determined in nine patients by examining the portal vein anatomy after ICG injection. Eight small tumors not observed preoperatively were detected; the smallest was 2 mm. ICG fluorescence imaging navigation is a promising, simple, and safe tool for routine real-time intraoperative imaging during hepatic resection and clinical exploration in hepatocellular carcinoma, enabling high sensibility for identifying liver resection margins and detecting tiny superficial tumors.

  15. Safe Use Practices for Pesticides

    Science.gov Websites

    ; Environment Human Health Animal Health Safe Use Practices Food Safety Environment Air Water Soil Wildlife Ingredients Low-Risk Pesticides Organic Pesticide Ingredients Pesticide Incidents Human Exposure Pet Exposure Home Page Pesticide Health and Safety Information Safe Use Practices for Pesticides Related Topics

  16. Is Prevent a Safe Space?

    ERIC Educational Resources Information Center

    Ramsay, Peter

    2017-01-01

    In this article, I test the claims of the UK government and universities that the Prevent programme aims to create a safe space for the discussion of "extremist" ideas in universities. I do this by comparing the main elements of the Prevent duty that has been imposed on universities with those of safe spaces as imagined by student…

  17. Discretization of three-dimensional free surface flows and moving boundary problems via elliptic grid methods based on variational principles

    NASA Astrophysics Data System (ADS)

    Fraggedakis, D.; Papaioannou, J.; Dimakopoulos, Y.; Tsamopoulos, J.

    2017-09-01

    A new boundary-fitted technique to describe free surface and moving boundary problems is presented. We have extended the 2D elliptic grid generator developed by Dimakopoulos and Tsamopoulos (2003) [19] and further advanced by Chatzidai et al. (2009) [18] to 3D geometries. The set of equations arises from the fulfillment of the variational principles established by Brackbill and Saltzman (1982) [21], and refined by Christodoulou and Scriven (1992) [22]. These account for both smoothness and orthogonality of the grid lines of tessellated physical domains. The elliptic-grid equations are accompanied by new boundary constraints and conditions which are based either on the equidistribution of the nodes on boundary surfaces or on the existing 2D quasi-elliptic grid methodologies. The capabilities of the proposed algorithm are first demonstrated in tests with analytically described complex surfaces. The sequence in which these tests are presented is chosen to help the reader build up experience on the best choice of the elliptic grid parameters. Subsequently, the mesh equations are coupled with the Navier-Stokes equations, in order to reveal the full potential of the proposed methodology in free surface flows. More specifically, the problem of gas assisted injection in ducts of circular and square cross-sections is examined, where the fluid domain experiences extreme deformations. Finally, the flow-mesh solver is used to calculate the equilibrium shapes of static menisci in capillary tubes.

  18. 75 FR 29391 - National Safe Boating Week, 2010

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-26

    ... Safe Boating Week, 2010 By the President of the United States of America A Proclamation Our Nation's... National Safe Boating Week to practicing safe techniques so boaters of all ages can enjoy this pastime... annually the 7-day period prior to Memorial Day weekend as ``National Safe Boating Week.'' NOW, THEREFORE...

  19. Experimental Research on Boundary Shear Stress in Typical Meandering Channel

    NASA Astrophysics Data System (ADS)

    Chen, Kai-hua; Xia, Yun-feng; Zhang, Shi-zhao; Wen, Yun-cheng; Xu, Hua

    2018-06-01

    A novel instrument named Micro-Electro-Mechanical System (MEMS) flexible hot-film shear stress sensor was used to study the boundary shear stress distribution in the generalized natural meandering open channel, and the mean sidewall shear stress distribution along the meandering channel, and the lateral boundary shear stress distribution in the typical cross-section of the meandering channel was analysed. Based on the measurement of the boundary shear stress, a semi-empirical semi-theoretical computing approach of the boundary shear stress was derived including the effects of the secondary flow, sidewall roughness factor, eddy viscosity and the additional Reynolds stress, and more importantly, for the first time, it combined the effects of the cross-section central angle and the Reynolds number into the expressions. Afterwards, a comparison between the previous research and this study was developed. Following the result, we found that the semi-empirical semi-theoretical boundary shear stress distribution algorithm can predict the boundary shear stress distribution precisely. Finally, a single factor analysis was conducted on the relationship between the average sidewall shear stress on the convex and concave bank and the flow rate, water depth, slope ratio, or the cross-section central angle of the open channel bend. The functional relationship with each of the above factors was established, and then the distance from the location of the extreme sidewall shear stress to the bottom of the open channel was deduced based on the statistical theory.

  20. A sharp and flat section of the core-mantle boundary

    USGS Publications Warehouse

    Vidale, J.E.; Benz, H.M.

    1992-01-01

    THE transition zone between the Earth's core and mantle plays an important role as a boundary layer for mantle and core convection1. This zone conducts a large amount of heat from the core to the mantle, and contains at least one thermal boundary layer2,3; the proximity of reactive silicates and molten iron leads to the possibility of zones of intermediate composition4. Here we investigate one region of the core-mantle boundary using seismic waves that are converted from shear to compressional waves by reflection at the boundary. The use of this phase (known as ScP), the large number of receiving stations, and the large aperture of our array all provide higher resolution than has previously been possible5-7. For the 350-km-long section of the core-mantle boundary under the northeast Pacific sampled by the reflections, the local boundary topography has an amplitude of less than 500 m, no sharp radial gradients exist in the 400 km above the boundary, and the mantle-lo-core transition occurs over less than 1 km. The simplicity of the structure near and above the core-mantle boundary argues against chemical heterogeneity at the base of the mantle in this location.

  1. Proposed Auxiliary Boundary Stratigraphic Section and Point (ASSP) for the base of the Ordovician System at Lawson Cove, Utah, USA

    USGS Publications Warehouse

    Miller, James F.; Evans, Kevin R.; Ethington, Raymond L.; Freeman, Rebecca; Loch, James D.; Repetski, John E.; Ripperdan, Robert; Taylor, John F.

    2016-01-01

    The Global boundary Stratotype Section and Point (GSSP) for the base of the Ordovician System is at the First Appearance Datum (FAD) of the conodont Iapetognathus fluctivagus at Green Point in Newfoundland, Canada. Strata there are typical graptolitic facies that were deposited near the base of the continental slope.We propose establishing an Auxiliary boundary Stratotype Section and Point (ASSP) at the FAD of I. fluctivagus at the Lawson Cove section in the Ibex area of Millard County, Utah, USA. There, strata consist of typical shelly facies limestones that were deposited on a tropical carbonate platform and contain abundant conodonts, trilobites, brachiopods, and other fossil groups. Cambrian and Ordovician strata in this area are ~5300m thick, with the Lawson Cove section spanning 243m in three overlapping segments. Six other measured and studied sections in the area show stratigraphic relationships similar to those at Lawson Cove. Faunas have been used to divide these strata into 14 conodont and 7 trilobite zonal units. The widespread olenid trilobite Jujuyaspis occurs ~90cm above the proposed boundary at Lawson Cove; this genus is generally regarded as earliest Ordovician. Rhynchonelliform and linguliform brachiopods are common to abundant and are useful for correlation. The FAD of Iapetognathus fluctivagus and occurrences of Jujuyaspis and the Lower Ordovician planktonic graptolite Anisograptus matanensis all occur within a 2.4m interval of strata at a nearby section. Non-biological correlation tools include a detailed sequence stratigraphic classification and a detailed carbon-isotope profile. Especially useful for correlation is a positive 13C excursion peak ~15cm below the proposed boundary horizon. All of these correlation tools form an integrated framework that makes the Lawson Cove section especially useful as an ASSP for global correlation of strata with faunas typical of shallow, warm-water, shelly facies.

  2. The Kinematics of Turbulent Boundary Layer Structure

    NASA Technical Reports Server (NTRS)

    Robinson, Stephen Kern

    1991-01-01

    The long history of research into the internal structure of turbulent boundary layers has not provided a unified picture of the physics responsible for turbulence production and dissipation. The goals of the present research are to: (1) define the current state of boundary layer structure knowledge; and (2) utilize direct numerical simulation results to help close the unresolved issues identified in part A and to unify the fragmented knowledge of various coherent motions into a consistent kinematic model of boundary layer structure. The results of the current study show that all classes of coherent motion in the low Reynolds number turbulent boundary layer may be related to vortical structures, but that no single form of vortex is representative of the wide variety of vortical structures observed. In particular, ejection and sweep motions, as well as entrainment from the free-streem are shown to have strong spatial and temporal relationships with vortical structures. Disturbances of vortex size, location, and intensity show that quasi-streamwise vortices dominate the buffer region, while transverse vortices and vortical arches dominate the wake region. Both types of vortical structure are common in the log region. The interrelationships between the various structures and the population distributions of vortices are combined into a conceptual kinematic model for the boundary layer. Aspects of vortical structure dynamics are also postulated, based on time-sequence animations of the numerically simulated flow.

  3. Evolution of grain boundary character distributions in alloy 825 tubes during high temperature annealing: Is grain boundary engineering achieved through recrystallization or grain growth?

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

    Bai, Qin; Zhao, Qing

    Grain boundary engineering (GBE) of nickel-based alloy 825 tubes was carried out with different cold drawing deformations by using a draw-bench on a factory production line and subsequent annealing at various temperatures. The microstructure evolution of alloy 825 during thermal-mechanical processing (TMP) was characterized by means of the electron backscatter diffraction (EBSD) technique to study the TMP effects on the grain boundary network and the evolution of grain boundary character distributions during high temperature annealing. The results showed that the proportion of ∑ 3{sup n} coincidence site lattice (CSL) boundaries of alloy 825 tubes could be increased to > 75%more » by the TMP of 5% cold drawing and subsequent annealing at 1050 °C for 10 min. The microstructures of the partially recrystallized samples and the fully recrystallized samples suggested that the proportion of low ∑ CSL grain boundaries depended on the annealing time. The frequency of low ∑ CSL grain boundaries increases rapidly with increasing annealing time associating with the formation of large-size highly-twinned grains-cluster microstructure during recrystallization. However, upon further increasing annealing time, the frequency of low ∑ CSL grain boundaries decreased markedly during grain growth. So it is concluded that grain boundary engineering is achieved through recrystallization rather than grain growth. - Highlights: •The grain boundary engineering (GBE) is applicable to 825 tubes. •GBE is achieved through recrystallization rather than grain growth. •The low ∑ CSL grain boundaries in 825 tubes can be increased to > 75%.« less

  4. Boundary Effects and Shear Thickening of Colloidal Suspensions: A study based on measurement of Suspension Microstructure

    NASA Astrophysics Data System (ADS)

    Perera, M. Tharanga D.

    Microstructure is key to understanding rheological behaviors of flowing particulate suspensions. During the past decade, Stokesian Dynamics simulations have been the dominant method of determining suspension microstructure. Structure results obtained numerically reveal that an anisotropic structure is formed under high Peclet (Pe) number conditions. Researchers have used various experimental techniques such as small angle neutron scattering (SANS) and light scattering methods to validate microstructure. This work outlines an experimental technique based on confocal microscopy to study microstructure of a colloidal suspension in an index-matched fluid flowing in a microchannel. High resolution scans determining individual particle locations in suspensions 30-50 vol % yield quantitative results of the local microstructure in the form of the pair distribution function, g(r). From these experimentally determined g(r), the effect of shear rate, quantified by the Peclet number as a ratio of shear and Brownian stress, on the suspension viscosity and normal stress follow that seen in macroscopic rheological measurements and simulations. It is generally believed that shear thickening behavior of colloidal suspensions is driven by the formation of hydroclusters. From measurements of particle locations, hydroclusters are identified. The number of hydroclusters grows exponentially with increasing Pe, and the onset of shear thickening is driven by the increase in formation of clusters having 5-8 particles. At higher Pe, we notice the emergence of 12 or more particle clusters. The internal structure of these hydroclusters has been investigated, and there is some evidence that particles internal to hydroclusters preferentially align along the 45° and 135° axis. Beyond observations of bulk suspension behavior, the influence of boundaries on suspension microstructure is also investigated. Experiments were performed for suspensions flowing over smooth walls, made of glass

  5. Safe Landings in Extreme Terrain

    NASA Technical Reports Server (NTRS)

    Rivellini, Tom; Ortiz, Gary; Steltzner, Adam

    2000-01-01

    Following the failure of the Mars Polar Lander and the re-evaluation of the Mars Sample Return mission status, a Safe Landing Tiger team was established on January 7, 2000. The charter of the team was to re-evaluate large scale (1000-2000 Kg) Mars lander designs with the principal objective being the assurance of safe landing in hazardous terrain. The tiger team developed a number of concepts, two of the most notable and promising concepts, are both based on a Mobile Lander paradigm. Unlike the Pathfinder and Surveyor class landers, this paradigm groups all of the landed equipment into one of two categories: (1) EDL only equipment (i.e., not used after touchdown) and (2) multi-use equipment, those used during and or after touchdown. The objective is to maximize the use of all equipment being brought to the surface by placing the bulk of the avionics and mechanical systems onto a much larger 'rover' and leaving only the bare essentials on a 'dead-on-arrival' landing system. All of the hardware that the surface roving mission needs is enlisted into performing the EDL tasks. Any EDL specific avionics not used after touchdown are placed on the landing system.

  6. A VERSATILE SHARP INTERFACE IMMERSED BOUNDARY METHOD FOR INCOMPRESSIBLE FLOWS WITH COMPLEX BOUNDARIES

    PubMed Central

    Mittal, R.; Dong, H.; Bozkurttas, M.; Najjar, F.M.; Vargas, A.; von Loebbecke, A.

    2010-01-01

    A sharp interface immersed boundary method for simulating incompressible viscous flow past three-dimensional immersed bodies is described. The method employs a multi-dimensional ghost-cell methodology to satisfy the boundary conditions on the immersed boundary and the method is designed to handle highly complex three-dimensional, stationary, moving and/or deforming bodies. The complex immersed surfaces are represented by grids consisting of unstructured triangular elements; while the flow is computed on non-uniform Cartesian grids. The paper describes the salient features of the methodology with special emphasis on the immersed boundary treatment for stationary and moving boundaries. Simulations of a number of canonical two- and three-dimensional flows are used to verify the accuracy and fidelity of the solver over a range of Reynolds numbers. Flow past suddenly accelerated bodies are used to validate the solver for moving boundary problems. Finally two cases inspired from biology with highly complex three-dimensional bodies are simulated in order to demonstrate the versatility of the method. PMID:20216919

  7. The relationship between grain boundary structure, defect mobility, and grain boundary sink efficiency

    PubMed Central

    Uberuaga, Blas Pedro; Vernon, Louis J.; Martinez, Enrique; Voter, Arthur F.

    2015-01-01

    Nanocrystalline materials have received great attention due to their potential for improved functionality and have been proposed for extreme environments where the interfaces are expected to promote radiation tolerance. However, the precise role of the interfaces in modifying defect behavior is unclear. Using long-time simulations methods, we determine the mobility of defects and defect clusters at grain boundaries in Cu. We find that mobilities vary significantly with boundary structure and cluster size, with larger clusters exhibiting reduced mobility, and that interface sink efficiency depends on the kinetics of defects within the interface via the in-boundary annihilation rate of defects. Thus, sink efficiency is a strong function of defect mobility, which depends on boundary structure, a property that evolves with time. Further, defect mobility at boundaries can be slower than in the bulk, which has general implications for the properties of polycrystalline materials. Finally, we correlate defect energetics with the volumes of atomic sites at the boundary. PMID:25766999

  8. The relationship between grain boundary structure, defect mobility, and grain boundary sink efficiency

    DOE PAGES

    Uberuaga, Blas Pedro; Vernon, Louis J.; Martinez, Enrique; ...

    2015-03-13

    Nanocrystalline materials have received great attention due to their potential for improved functionality and have been proposed for extreme environments where the interfaces are expected to promote radiation tolerance. However, the precise role of the interfaces in modifying defect behavior is unclear. Using long-time simulations methods, we determine the mobility of defects and defect clusters at grain boundaries in Cu. We find that mobilities vary significantly with boundary structure and cluster size, with larger clusters exhibiting reduced mobility, and that interface sink efficiency depends on the kinetics of defects within the interface via the in-boundary annihilation rate of defects. Thus,more » sink efficiency is a strong function of defect mobility, which depends on boundary structure, a property that evolves with time. Further, defect mobility at boundaries can be slower than in the bulk, which has general implications for the properties of polycrystalline materials. Finally, we correlate defect energetics with the volumes of atomic sites at the boundary.« less

  9. 30 CFR 77.312 - Fail safe monitoring systems.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Fail safe monitoring systems. 77.312 Section 77... Thermal Dryers § 77.312 Fail safe monitoring systems. Thermal dryer systems and controls shall be protected by a fail safe monitoring system which will safely shut down the system and any related equipment...

  10. 30 CFR 77.312 - Fail safe monitoring systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Fail safe monitoring systems. 77.312 Section 77... Thermal Dryers § 77.312 Fail safe monitoring systems. Thermal dryer systems and controls shall be protected by a fail safe monitoring system which will safely shut down the system and any related equipment...

  11. 30 CFR 77.312 - Fail safe monitoring systems.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Fail safe monitoring systems. 77.312 Section 77... Thermal Dryers § 77.312 Fail safe monitoring systems. Thermal dryer systems and controls shall be protected by a fail safe monitoring system which will safely shut down the system and any related equipment...

  12. 30 CFR 77.312 - Fail safe monitoring systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fail safe monitoring systems. 77.312 Section 77... Thermal Dryers § 77.312 Fail safe monitoring systems. Thermal dryer systems and controls shall be protected by a fail safe monitoring system which will safely shut down the system and any related equipment...

  13. 30 CFR 77.312 - Fail safe monitoring systems.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Fail safe monitoring systems. 77.312 Section 77... Thermal Dryers § 77.312 Fail safe monitoring systems. Thermal dryer systems and controls shall be protected by a fail safe monitoring system which will safely shut down the system and any related equipment...

  14. 29 CFR 1915.15 - Maintenance of safe conditions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Enclosed Spaces and Other Dangerous Atmospheres in Shipyard Employment § 1915.15 Maintenance of safe... into spaces that have been certified “Safe for Workers” or “Safe for Hot Work” shall be disconnected... certificates. A competent person shall visually inspect and test each space certified as “Safe for Workers” or...

  15. 29 CFR 1915.15 - Maintenance of safe conditions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Enclosed Spaces and Other Dangerous Atmospheres in Shipyard Employment § 1915.15 Maintenance of safe... into spaces that have been certified “Safe for Workers” or “Safe for Hot Work” shall be disconnected... certificates. A competent person shall visually inspect and test each space certified as “Safe for Workers” or...

  16. The Coconut and the Peach: Understanding, Establishing, and Maintaining Interpersonal Boundaries with International Students

    ERIC Educational Resources Information Center

    Yamashita, Miki; Schwartz, Harriet L.

    2012-01-01

    This chapter explores international students' perspectives of boundaries in the American graduate-level classroom, specifically considering the culturally based essence of boundaries. The authors focus on graduate-level Japanese international students. This population is particularly helpful in their consideration of boundaries because research…

  17. Some boundary-value problems for anisotropic quarter plane

    NASA Astrophysics Data System (ADS)

    Arkhypenko, K. M.; Kryvyi, O. F.

    2018-04-01

    To solve the mixed boundary-value problems of the anisotropic elasticity for the anisotropic quarter plane, a method based on the use of the space of generalized functions {\\Im }{\\prime }({\\text{R}}+2) with slow growth properties was developed. The two-dimensional integral Fourier transform was used to construct the system of fundamental solutions for the anisotropic quarter plane in this space and a system of eight boundary integral relations was obtained, which allows one to reduce the mixed boundary-value problems for the anisotropic quarter plane directly to systems of singular integral equations with fixed singularities. The exact solutions of these systems were found by using the integral Mellin transform. The asymptotic behavior of solutions was investigated at the vertex of the quarter plane.

  18. Staying Healthy and Safe at Work

    MedlinePlus

    ... The Prematurity Campaign About us Annual report Our work Community impact Global programs Research Need help? Frequently ... safe at work Staying healthy and safe at work E-mail to a friend Please fill in ...

  19. Forward-facing steps induced transition in a subsonic boundary layer

    NASA Astrophysics Data System (ADS)

    Zh, Hui; Fu, Song

    2017-10-01

    A forward-facing step (FFS) immersed in a subsonic boundary layer is studied through a high-order flux reconstruction (FR) method to highlight the flow transition induced by the step. The step height is a third of the local boundary-layer thickness. The Reynolds number based on the step height is 720. Inlet disturbances are introduced giving rise to streamwise vortices upstream of the step. It is observed that these small-scale streamwise structures interact with the step and hairpin vortices are quickly developed after the step leading to flow transition in the boundary layer.

  20. Grain boundary engineering for structure materials of nuclear reactors

    NASA Astrophysics Data System (ADS)

    Tan, L.; Allen, T. R.; Busby, J. T.

    2013-10-01

    Grain boundary engineering (GBE), primarily implemented by thermomechanical processing, is an effective and economical method of enhancing the properties of polycrystalline materials. Among the factors affecting grain boundary character distribution, literature data showed definitive effect of grain size and texture. GBE is more effective for austenitic stainless steels and Ni-base alloys compared to other structural materials of nuclear reactors, such as refractory metals, ferritic and ferritic-martensitic steels, and Zr alloys. GBE has shown beneficial effects on improving the strength, creep strength, and resistance to stress corrosion cracking and oxidation of austenitic stainless steels and Ni-base alloys.

  1. Stationary States of Boundary Driven Exclusion Processes with Nonreversible Boundary Dynamics

    NASA Astrophysics Data System (ADS)

    Erignoux, C.; Landim, C.; Xu, T.

    2018-05-01

    We prove a law of large numbers for the empirical density of one-dimensional, boundary driven, symmetric exclusion processes with different types of non-reversible dynamics at the boundary. The proofs rely on duality techniques.

  2. 33 CFR 83.06 - Safe speed (Rule 6).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Safe speed (Rule 6). 83.06... Safe speed (Rule 6). Every vessel shall at all times proceed at a safe speed so that she can take... prevailing circumstances and conditions. In determining a safe speed the following factors shall be among...

  3. 33 CFR 83.06 - Safe speed (Rule 6).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Safe speed (Rule 6). 83.06... Safe speed (Rule 6). Every vessel shall at all times proceed at a safe speed so that she can take... prevailing circumstances and conditions. In determining a safe speed the following factors shall be among...

  4. Why Do Parents with Toddlers Store Poisonous Products Safely?

    PubMed Central

    Beirens, Tinneke M. J.; van Beeck, Eduard F.; Brug, Johannes; den Hertog, Paul; Raat, Hein

    2010-01-01

    Unintentional poisoning is a major cause of nonfatal injuries in children aged 0–24 months. Associations between self-reported habits on the child safe storage of medication and cleaning products and family, and psychosocial factors were assessed, using a model based on the Protection Motivation Theory. By identifying correlates of safety behavior in this manner, more insight in factors which influence this behavior is obtained. Health promotion activities in order to promote safety behavior should address these factors in order to increase the effectiveness of the health message. Data were gathered from a cross-sectional survey using self-administered questionnaires, mailed to a population sample of 2470 parents with toddlers. The results indicate that the promotion of safe storage of medication and cleaning products should address the family situation, personal cognitive factors as well as social factors. Interventions should particularly focus on parents' self-efficacy of storing poisonous products in a child safe manner and on the vulnerability of their child in their home concerning an unintentional poisoning incident. PMID:20671943

  5. Iatrogenic Hepatitis C Virus Transmission and Safe Injection Practices.

    PubMed

    Defendorf, Charles M; Paul, Sindy; Scott, George J

    2018-05-01

    Hepatitis C virus (HCV) infection poses significant adverse health effects. Improper use of vials, needles, syringes, intravenous bags, tubing, and connectors for injections and infusions is a current preventable cause of iatrogenic HCV transmission. Numerous cases have demonstrated the need for continued vigilance and the widespread nature of this iatrogenic infection risk across a variety of medical practice settings in the United States. Failure to implement the evidence-based Centers for Disease Control and Prevention (CDC) infection prevention guidelines exposes patients to preventable harm. The guidelines establish the requirement to notify patients in cases of suspected virus transmission, as well as to screen those patients who would not otherwise have been at risk for HCV seroconversion and other bloodborne pathogens. Legal and regulatory ramifications, including state, criminal, and tort laws, hold physicians and other health care professionals accountable to use safe injection practices. This article reviews the major health risks of HCV infection, significant effects of iatrogenic infection transmission, CDC guidelines for safe injection practices, and legal regulations and ramifications designed to promote safe injection practices.

  6. Alert: the dark side of chats--internet without boundaries.

    PubMed

    Aderet, Avshalom

    2009-01-01

    mind was filled with suicidal thoughts he stumbled upon a group on the web that embraced the culture of death and suicide discussions. In his darkest moments, when he was on the verge of an abyss, he was probably pushed by these discussions into his death, and he was only 19-years-old. When Eshnav was created we saw the dangers of an Internet with no boundaries, a place where this remarkable technology was grossly misused. This is from the association's statement: "In a world without fences and boundaries clearer rules of conduct are needed." We emphasized that "the web is like a new world that has yet to determine its own boundaries. As such, it poses new challenges, both moral and ideological, which cannot be met based on past experience as this phenomenon is still too new and uncharted. We must do the utmost to be vigil about making the Internet as safe as possible even when this new frontier is constantly shifting and evolving." Let us bow our heads in sadness in memory of Eran whose strength did not withstand the great distress he was in, and who let himself be dragged by the death culture and darkness on the web into an untimely grave. We shall find strength in our determination to create a responsible web community in which freedom of speech will not be abused to hurt the individual rights of each and every human being to life, respect, reputation and privacy.

  7. Boundary layers in cataclysmic variables - The HEAO 1 X-ray constraints

    NASA Technical Reports Server (NTRS)

    Jensen, K. A.

    1984-01-01

    The predictions of the boundary layer model for the X-ray emission from novae are summarized. A discrepancy between observations and theory in the X-ray observations is found. Constraints on the nature of the boundary layers in novae, based on the lack of detections of novae in the HEAO-1 soft X-ray survey are provided. Temperature and column densities for optically thick boundary layers in novae are estimated. Previously announced in STAR as N84-13046

  8. Direct detection of Mycobacterium tuberculosis rifampin resistance in bio-safe stained sputum smears.

    PubMed

    Lavania, Surabhi; Anthwal, Divya; Bhalla, Manpreet; Singh, Nagendra; Haldar, Sagarika; Tyagi, Jaya Sivaswami

    2017-01-01

    Direct smear microscopy of sputum forms the mainstay of TB diagnosis in resource-limited settings. Stained sputum smear slides can serve as a ready-made resource to transport sputum for molecular drug susceptibility testing. However, bio-safety is a major concern during transport of sputum/stained slides and for laboratory workers engaged in processing Mycobacterium tuberculosis infected sputum specimens. In this study, a bio-safe USP (Universal Sample Processing) concentration-based sputum processing method (Bio-safe method) was assessed on 87 M. tuberculosis culture positive sputum samples. Samples were processed for Ziehl-Neelsen (ZN) smear, liquid culture and DNA isolation. DNA isolated directly from sputum was subjected to an IS6110 PCR assay. Both sputum DNA and DNA extracted from bio-safe ZN concentrated smear slides were subjected to rpoB PCR and simultaneously assessed by DNA sequencing for determining rifampin (RIF) resistance. All sputum samples were rendered sterile by Bio-safe method. Bio-safe smears exhibited a 5% increment in positivity over direct smear with a 14% increment in smear grade status. All samples were positive for IS6110 and rpoB PCR. Thirty four percent samples were RIF resistant by rpoB PCR product sequencing. A 100% concordance (κ value = 1) was obtained between sequencing results derived from bio-safe smear slides and bio-safe sputum. This study demonstrates that Bio-safe method can address safety issues associated with sputum processing, provide an efficient alternative to sample transport in the form of bio-safe stained concentrated smear slides and can also provide information on drug (RIF) resistance by direct DNA sequencing.

  9. Nonlinear Transient Growth and Boundary Layer Transition

    NASA Technical Reports Server (NTRS)

    Paredes, Pedro; Choudhari, Meelan M.; Li, Fei

    2016-01-01

    Parabolized stability equations (PSE) are used in a variational approach to study the optimal, non-modal disturbance growth in a Mach 3 at plate boundary layer and a Mach 6 circular cone boundary layer. As noted in previous works, the optimal initial disturbances correspond to steady counter-rotating streamwise vortices, which subsequently lead to the formation of streamwise-elongated structures, i.e., streaks, via a lift-up effect. The nonlinear evolution of the linearly optimal stationary perturbations is computed using the nonlinear plane-marching PSE for stationary perturbations. A fully implicit marching technique is used to facilitate the computation of nonlinear streaks with large amplitudes. To assess the effect of the finite-amplitude streaks on transition, the linear form of plane- marching PSE is used to investigate the instability of the boundary layer flow modified by spanwise periodic streaks. The onset of bypass transition is estimated by using an N- factor criterion based on the amplification of the streak instabilities. Results show that, for both flow configurations of interest, streaks of sufficiently large amplitude can lead to significantly earlier onset of transition than that in an unperturbed boundary layer without any streaks.

  10. Silicon nitride boundary lubrication: Effect of oxygenates

    NASA Astrophysics Data System (ADS)

    Gates, Richard S.; Hsu, Stephen M.

    1995-07-01

    A ball-on-three-flat (BTF) wear tester was used to investigate the boundary lubricating characteristics of oxygenates on a commercial silicon nitride. A wide variety of oxygen-containing compounds containing hydroxyl functioal groups were more effective compared to a base case of neat paraffin oil. Decreases of up to 58% in friction coefficient, and 95% in wear were obtained. In most cases, films were obseved in and around the wear scar, suggesting chemical reactions had taken place in the contact. Additional wear tests, conducted using neat shorter-chain linear primary alcohols, i.e., 6-10 carbons, demonstrated boundary lubrication protection, with longer chain length providing better antiwear performance. A study of several C8 compounds with specific oxygen-containing functional groups (primary alcohol, secondary alcohols, acid, aldehyde, and ketone) demonstrated that the primary alcohol had the strongest boundary lubricating effect. Varying the amount of water in the alcohols had little effect on friction and wear, suggesting that the boundary lubrication effects observed were not merely due to dissolved water in these fluids, but some characteristic chemical interaction with the hydroxyl functional group of the alcohols and acids.

  11. Towards a General Turbulence Model for Planetary Boundary Layers Based on Direct Statistical Simulation

    NASA Astrophysics Data System (ADS)

    Skitka, J.; Marston, B.; Fox-Kemper, B.

    2016-02-01

    Sub-grid turbulence models for planetary boundary layers are typically constructed additively, starting with local flow properties and including non-local (KPP) or higher order (Mellor-Yamada) parameters until a desired level of predictive capacity is achieved or a manageable threshold of complexity is surpassed. Such approaches are necessarily limited in general circumstances, like global circulation models, by their being optimized for particular flow phenomena. By building a model reductively, starting with the infinite hierarchy of turbulence statistics, truncating at a given order, and stripping degrees of freedom from the flow, we offer the prospect a turbulence model and investigative tool that is equally applicable to all flow types and able to take full advantage of the wealth of nonlocal information in any flow. Direct statistical simulation (DSS) that is based upon expansion in equal-time cumulants can be used to compute flow statistics of arbitrary order. We investigate the feasibility of a second-order closure (CE2) by performing simulations of the ocean boundary layer in a quasi-linear approximation for which CE2 is exact. As oceanographic examples, wind-driven Langmuir turbulence and thermal convection are studied by comparison of the quasi-linear and fully nonlinear statistics. We also characterize the computational advantages and physical uncertainties of CE2 defined on a reduced basis determined via proper orthogonal decomposition (POD) of the flow fields.

  12. 33 CFR 62.27 - Safe water marks.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Safe water marks. 62.27 Section 62.27 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.27 Safe water marks. Safe...

  13. Metallurgical evaluation of a feedwater nozzle to safe-end weld

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

    Bowerman, B.S.; Czajkowski, C.J.; Roberts, T.C.

    1999-11-01

    Weld cracks in safety class systems are a serious concern, because these systems are part of the primary barrier providing containment of radioactive coolant. Loss of weld integrity yields leaks, or, under catastrophic failure, can be the basis for a severe loss of coolant accident. A circumferential indication was found by ultrasonic examination (UT) in the N4A-2 inlet feedwater nozzle to safe-end weld during the second refueling outage of River Bend Station Unit 1 in March 1989. The indication, approximately 15cm (6in) long with a reported maximum depth of 0.5cm (0.1in), was located in the Alloy 182 weld butter onmore » the safe-end side of the weld. (The safe-end base metal was ASME SA 508 Class 1 carbon steel.) The reported characteristics of the UT indication were indicative of intergranular stress corrosion cracking. This indication was reexamined during the second and third fuel cycles in March 1990 and September 1991, respectively, and during the third refuel outage in November 1990. Crack growth was reported during each examination. The safe-end was replaced during the fourth refueling outage in the summer of 1992. The US Nuclear Regulatory Commission (NRC) subsequently contracted with Brookhaven National laboratory (BNL) to conduct a confirmatory investigation to establish the failure mode and determine the root causes of cracking in the safe-end weld.« less

  14. 75 FR 1734 - Children’s Online Privacy Protection Rule Safe Harbor Proposed Self-Regulatory Guidelines; i-SAFE...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-13

    ...The Federal Trade Commission publishes this notice and request for public comment concerning proposed self-regulatory guidelines submitted by i-SAFE, Inc. under the safe harbor provision of the Children's Online Privacy Protection Rule.

  15. Acid-base chemical reaction model for nucleation rates in the polluted atmospheric boundary layer.

    PubMed

    Chen, Modi; Titcombe, Mari; Jiang, Jingkun; Jen, Coty; Kuang, Chongai; Fischer, Marc L; Eisele, Fred L; Siepmann, J Ilja; Hanson, David R; Zhao, Jun; McMurry, Peter H

    2012-11-13

    Climate models show that particles formed by nucleation can affect cloud cover and, therefore, the earth's radiation budget. Measurements worldwide show that nucleation rates in the atmospheric boundary layer are positively correlated with concentrations of sulfuric acid vapor. However, current nucleation theories do not correctly predict either the observed nucleation rates or their functional dependence on sulfuric acid concentrations. This paper develops an alternative approach for modeling nucleation rates, based on a sequence of acid-base reactions. The model uses empirical estimates of sulfuric acid evaporation rates obtained from new measurements of neutral molecular clusters. The model predicts that nucleation rates equal the sulfuric acid vapor collision rate times a prefactor that is less than unity and that depends on the concentrations of basic gaseous compounds and preexisting particles. Predicted nucleation rates and their dependence on sulfuric acid vapor concentrations are in reasonable agreement with measurements from Mexico City and Atlanta.

  16. Heat Pipe Reactor Dynamic Response Tests: SAFE-100 Reactor Core Prototype

    NASA Technical Reports Server (NTRS)

    Bragg-Sitton, Shannon M.

    2005-01-01

    The SAFE-I00a test article at the NASA Marshall Space Flight Center was used to simulate a variety of potential reactor transients; the SAFEl00a is a resistively heated, stainless-steel heat-pipe (HP)-reactor core segment, coupled to a gas-flow heat exchanger (HX). For these transients the core power was controlled by a point kinetics model with reactivity feedback based on core average temperature; the neutron generation time and the temperature feedback coefficient are provided as model inputs. This type of non-nuclear test is expected to provide reasonable approximation of reactor transient behavior because reactivity feedback is very simple in a compact fast reactor (simple, negative, and relatively monotonic temperature feedback, caused mostly by thermal expansion) and calculations show there are no significant reactivity effects associated with fluid in the HP (the worth of the entire inventory of Na in the core is .SAFE-100 tests, the point kinetics model was based on core thermal expansion via deflection measurements. It was found that core deflection was a strung function of how the SAFE-100 modules were fabricated and assembled (in terms of straightness, gaps, and other tolerances). To remove the added variable of how this particular core expands as compared to a different concept, it was decided to use a temperature based feedback model (based on several thermocouples placed throughout the core).

  17. Food Safety Posters for Safe Handling of Leafy Greens

    ERIC Educational Resources Information Center

    Rajagopal, Lakshman; Arendt, Susan W.; Shaw, Angela M.; Strohbehn, Catherine H.; Sauer, Kevin L.

    2016-01-01

    This article describes food safety educational tools depicting safe handling of leafy greens that are available as downloadable posters to Extension educators and practitioners (www.extension.iastate.edu). Nine visual-based minimal-text colored posters in English, Chinese, and Spanish were developed for use when formally or informally educating…

  18. Boundary-integral methods in elasticity and plasticity. [solutions of boundary value problems

    NASA Technical Reports Server (NTRS)

    Mendelson, A.

    1973-01-01

    Recently developed methods that use boundary-integral equations applied to elastic and elastoplastic boundary value problems are reviewed. Direct, indirect, and semidirect methods using potential functions, stress functions, and displacement functions are described. Examples of the use of these methods for torsion problems, plane problems, and three-dimensional problems are given. It is concluded that the boundary-integral methods represent a powerful tool for the solution of elastic and elastoplastic problems.

  19. The contribution of nurses' perceptions and actions in defining scope and stabilising professional boundaries of nursing practice.

    PubMed

    Lillibridge, J; Axford, R; Rowley, G

    2000-10-01

    This paper reports on the findings of a naturalistic inquiry study that explored the scope and boundaries of nursing practice. Findings from interview and observation data suggest that nurses negotiate and adjust professional boundaries on an individual, case-by-case basis, thereby managing the scope of their practice as they see it in that circumstance. The strategies they used are presented in four major categories: 1) maintaining a comfort zone, 2) expanding into safe territory, 3) moving into the grey zone and 4) stepping over the line. Findings show that nurses' efforts to maintain the comfort zone serve to perpetuate the status quo and may threaten holistic care. Expanding nursing actions to include functional roles such as coordinating care, sharing information, advocating (for patients), collaborating and innovating offers the profession critical building blocks for defining the scope of nursing practice. Clarifying the grey zone (or overlapping territory) is an essential task for the profession in determining the boundaries of nursing practice. The data revealed that, partly due to the ambiguity of the grey zone, nurses may step over the line into medical decision-making and outside the legal sanctions for the professional nursing role. The implications of this study highlight the need for nursing to define its scope of practice and in so doing stabilise professional boundaries.

  20. Exclusion Process with Slow Boundary

    NASA Astrophysics Data System (ADS)

    Baldasso, Rangel; Menezes, Otávio; Neumann, Adriana; Souza, Rafael R.

    2017-06-01

    We study the hydrodynamic and the hydrostatic behavior of the simple symmetric exclusion process with slow boundary. The term slow boundary means that particles can be born or die at the boundary sites, at a rate proportional to N^{-θ }, where θ > 0 and N is the scaling parameter. In the bulk, the particles exchange rate is equal to 1. In the hydrostatic scenario, we obtain three different linear profiles, depending on the value of the parameter θ ; in the hydrodynamic scenario, we obtain that the time evolution of the spatial density of particles, in the diffusive scaling, is given by the weak solution of the heat equation, with boundary conditions that depend on θ . If θ \\in (0,1), we get Dirichlet boundary conditions, (which is the same behavior if θ =0, see Farfán in Hydrostatics, statical and dynamical large deviations of boundary driven gradient symmetric exclusion processes, 2008); if θ =1, we get Robin boundary conditions; and, if θ \\in (1,∞), we get Neumann boundary conditions.

  1. Parcels versus pixels: modeling agricultural land use across broad geographic regions using parcel-based field boundaries

    USGS Publications Warehouse

    Sohl, Terry L.; Dornbierer, Jordan; Wika, Steve; Sayler, Kristi L.; Quenzer, Robert

    2017-01-01

    Land use and land cover (LULC) change occurs at a local level within contiguous ownership and management units (parcels), yet LULC models primarily use pixel-based spatial frameworks. The few parcel-based models being used overwhelmingly focus on small geographic areas, limiting the ability to assess LULC change impacts at regional to national scales. We developed a modified version of the Forecasting Scenarios of land use change model to project parcel-based agricultural change across a large region in the United States Great Plains. A scenario representing an agricultural biofuel scenario was modeled from 2012 to 2030, using real parcel boundaries based on contiguous ownership and land management units. The resulting LULC projection provides a vastly improved representation of landscape pattern over existing pixel-based models, while simultaneously providing an unprecedented combination of thematic detail and broad geographic extent. The conceptual approach is practical and scalable, with potential use for national-scale projections.

  2. Curiosity's Autonomous Surface Safing Behavior Design

    NASA Technical Reports Server (NTRS)

    Neilson, Tracy A.; Manning, Robert M.

    2013-01-01

    The safing routines on all robotic deep-space vehicles are designed to put the vehicle in a power and thermally safe configuration, enabling communication with the mission operators on Earth. Achieving this goal is made a little more difficult on Curiosity because the power requirements for the core avionics and the telecommunication equipment exceed the capability of the single power source, the Multi-Mission Radioisotope Thermoelectric Generator. This drove the system design to create an operational mode, called "sleep mode", where the vehicle turns off most of the loads in order to charge the two Li-ion batteries. The system must keep the vehicle safe from over-heat and under-heat conditions, battery cell failures, under-voltage conditions, and clock failures, both while the computer is running and while the system is sleeping. The other goal of a safing routine is to communicate. On most spacecraft, this simply involves turning on the receiver and transmitter continuously. For Curiosity, Earth is above the horizon only a part of the day for direct communication to the Earth, and the orbiter overpass opportunities only occur a few times a day. The design must robustly place the Rover in a communicable condition at the correct time. This paper discusses Curiosity's autonomous safing behavior and describes how the vehicle remains power and thermally safe while sleeping, as well as a description of how the Rover communicates with the orbiters and Earth at specific times.

  3. 33 CFR 62.27 - Safe water marks.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Safe water marks. 62.27 Section... UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.27 Safe water marks. Safe water marks indicate that there is navigable water all around the mark. They are often used to indicate...

  4. 33 CFR 62.27 - Safe water marks.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Safe water marks. 62.27 Section... UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.27 Safe water marks. Safe water marks indicate that there is navigable water all around the mark. They are often used to indicate...

  5. 33 CFR 62.27 - Safe water marks.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Safe water marks. 62.27 Section... UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.27 Safe water marks. Safe water marks indicate that there is navigable water all around the mark. They are often used to indicate...

  6. Artificial Boundary Conditions for Computation of Oscillating External Flows

    NASA Technical Reports Server (NTRS)

    Tsynkov, S. V.

    1996-01-01

    In this paper, we propose a new technique for the numerical treatment of external flow problems with oscillatory behavior of the solution in time. Specifically, we consider the case of unbounded compressible viscous plane flow past a finite body (airfoil). Oscillations of the flow in time may be caused by the time-periodic injection of fluid into the boundary layer, which in accordance with experimental data, may essentially increase the performance of the airfoil. To conduct the actual computations, we have to somehow restrict the original unbounded domain, that is, to introduce an artificial (external) boundary and to further consider only a finite computational domain. Consequently, we will need to formulate some artificial boundary conditions (ABC's) at the introduced external boundary. The ABC's we are aiming to obtain must meet a fundamental requirement. One should be able to uniquely complement the solution calculated inside the finite computational domain to its infinite exterior so that the original problem is solved within the desired accuracy. Our construction of such ABC's for oscillating flows is based on an essential assumption: the Navier-Stokes equations can be linearized in the far field against the free-stream back- ground. To actually compute the ABC's, we represent the far-field solution as a Fourier series in time and then apply the Difference Potentials Method (DPM) of V. S. Ryaben'kii. This paper contains a general theoretical description of the algorithm for setting the DPM-based ABC's for time-periodic external flows. Based on our experience in implementing analogous ABC's for steady-state problems (a simpler case), we expect that these boundary conditions will become an effective tool for constructing robust numerical methods to calculate oscillatory flows.

  7. Automatic 3D motion estimation of left ventricle from C-arm rotational angiocardiography using a prior motion model and learning based boundary detector.

    PubMed

    Chen, Mingqing; Zheng, Yefeng; Wang, Yang; Mueller, Kerstin; Lauritsch, Guenter

    2013-01-01

    Compared to pre-operative imaging modalities, it is more convenient to estimate the current cardiac physiological status from C-arm angiocardiography since C-arm is a widely used intra-operative imaging modality to guide many cardiac interventions. The 3D shape and motion of the left ventricle (LV) estimated from rotational angiocardiography provide important cardiac function measurements, e.g., ejection fraction and myocardium motion dyssynchrony. However, automatic estimation of the 3D LV motion is difficult since all anatomical structures overlap on the 2D X-ray projections and the nearby confounding strong image boundaries (e.g., pericardium) often cause ambiguities to LV endocardium boundary detection. In this paper, a new framework is proposed to overcome the aforementioned difficulties: (1) A new learning-based boundary detector is developed by training a boosting boundary classifier combined with the principal component analysis of a local image patch; (2) The prior LV motion model is learned from a set of dynamic cardiac computed tomography (CT) sequences to provide a good initial estimate of the 3D LV shape of different cardiac phases; (3) The 3D motion trajectory is learned for each mesh point; (4) All these components are integrated into a multi-surface graph optimization method to extract the globally coherent motion. The method is tested on seven patient scans, showing significant improvement on the ambiguous boundary cases with a detection accuracy of 2.87 +/- 1.00 mm on LV endocardium boundary delineation in the 2D projections.

  8. Removing Hair Safely

    MedlinePlus

    ... For Consumers Home For Consumers Consumer Updates Removing Hair Safely Share Tweet Linkedin Pin it More sharing ... related to common methods of hair removal. Laser Hair Removal In this method, a laser destroys hair ...

  9. Evaluation of general non-reflecting boundary conditions for industrial CFD applications

    NASA Astrophysics Data System (ADS)

    Basara, Branislav; Frolov, Sergei; Lidskii, Boris; Posvyanskii, Vladimir

    2007-11-01

    The importance of having proper boundary conditions for the calculation domain is a known issue in Computational Fluid Dynamics (CFD). In many situations, it is very difficult to define a correct boundary condition. The flow may enter and leave the computational domain at the same time and at the same boundary. In such circumstances, it is important that numerical implementation of boundary conditions enforces certain physical constraints leading to correct results which then ensures a better convergence rate. The aim of this paper is to evaluate recently proposed non-reflecting boundary conditions (Frolov et al., 2001, Advances in Chemical Propulsion) on industrial CFD applications. Derivation of the local non-reflecting boundary conditions at the open boundary is based on finding the solution of linearized Euler equations vanishing at infinity for both incompressible and compressible formulations. This is implemented into the in-house CFD package AVL FIRE and some numerical details will be presented as well. The key applications in this paper are from automotive industry, e.g. an external car aerodynamics, an intake port, etc. The results will show benefits of using effective non-reflecting boundary conditions.

  10. A fail-safe CMOS logic gate

    NASA Technical Reports Server (NTRS)

    Bobin, V.; Whitaker, S.

    1990-01-01

    This paper reports a design technique to make Complex CMOS Gates fail-safe for a class of faults. Two classes of faults are defined. The fail-safe design presented has limited fault-tolerance capability. Multiple faults are also covered.

  11. Interactive eLearning - a safe place to practice.

    PubMed

    Einarson, Elisabeth; Moen, Anne; Kolberg, Ragnhild; Flingtorp, Gry; Linnerud, Eva

    2009-01-01

    Interactive web-based learning environment offers refreshing opportunities to create innovative solutions to explore and exploit informatics support on-the-job training. We report from a study where a hospital is created a interactive eLearning resource. The modules are creating a safe place to practice - to be used for introduction to the work and preparation for certification or re-certification of competencies.

  12. Minnesota Heart Safe Communities: Are community-based initiatives increasing pre-ambulance CPR and AED use?

    PubMed

    Boland, Lori L; Formanek, Michelle B; Harkins, Kim K; Frazee, Carol L; Kamrud, Jonathan W; Stevens, Andrew C; Lick, Charles J; Yannopoulos, Demetris

    2017-10-01

    Implementation research that describes how successfully resuscitation guidelines are translated into practice are lacking. We examined whether recent community-based initiatives being conducted as part of the Minnesota Heart Safe (HS) Communities program increase the delivery of CPR and use of automated external defibrillators (AED) by bystanders and first responders prior to ambulance arrival. Non-EMS witnessed out-of-hospital cardiac arrests (OHCA) with presumed cardiac etiology treated by a single ambulance service in 2013-2015 were studied. Data were obtained from the Minnesota HS program and the Cardiac Arrest Registry to Enhance Survival (CARES) Surveillance Registry. Pre-ambulance CPR and AED use within HS communities before and after completion of the program were compared. As of July 2016, 17 Minnesota communities within the ambulance service area had achieved HS designation and 294 OHCAs that occurred in these communities met inclusion criteria for analysis (120 before HS designation, 174 after). CPR was initiated by bystanders or first responders prior to ambulance arrival in 83% of OHCA events that occurred before HS designation and in 95% of events that occurred after designation (OR=4.23 [1.80-9.98]). Pre-ambulance AED use increased from 63% to 77% after the community intervention (OR=1.94 [1.16-3.24]). Overall unadjusted survival to hospital discharge increased slightly after HS designation, but this difference was not statistically significant (17% vs 20%, p=0.32). Implementation of the Heart Safe program in communities within our ambulance service area in Minnesota has increased use of CPR and AEDs by bystanders and first responders prior to ambulance arrival. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Community participation in fire management planning: The Trinity county fire safe council's fire plan

    Treesearch

    Yvonne Everett

    2008-01-01

    In 1999, Trinity County CA, initiated a participatory fire management planning effort. Since that time, the Trinity County Fire Safe Council has completed critical portions of a fire safe plan and has begun to implement projects defined in the plan. Completion of a GIS based, landscape scale fuels reduction element in the plan defined by volunteer fire fighters, agency...

  14. Safe mobility for older people notebook

    DOT National Transportation Integrated Search

    1999-04-01

    The Safe Mobility for Older People Notebook is a research product of the "Model Driver Screening and Evaluation Program" project sponsored by NHTSA, and is intended as a resource to support program initiatives promoting the safe mobility of older per...

  15. Numerical Treatment of Degenerate Diffusion Equations via Feller's Boundary Classification, and Applications

    NASA Technical Reports Server (NTRS)

    Cacio, Emanuela; Cohn, Stephen E.; Spigler, Renato

    2011-01-01

    A numerical method is devised to solve a class of linear boundary-value problems for one-dimensional parabolic equations degenerate at the boundaries. Feller theory, which classifies the nature of the boundary points, is used to decide whether boundary conditions are needed to ensure uniqueness, and, if so, which ones they are. The algorithm is based on a suitable preconditioned implicit finite-difference scheme, grid, and treatment of the boundary data. Second-order accuracy, unconditional stability, and unconditional convergence of solutions of the finite-difference scheme to a constant as the time-step index tends to infinity are further properties of the method. Several examples, pertaining to financial mathematics, physics, and genetics, are presented for the purpose of illustration.

  16. An Introduction to the Safe Schools/Healthy Students Initiative

    ERIC Educational Resources Information Center

    Modzeleski, William; Mathews-Younes, Anne; Arroyo, Carmen G.; Mannix, Danyelle; Wells, Michael E.; Hill, Gary; Yu, Ping; Murray, Stephen

    2012-01-01

    The Safe Schools/Healthy Students (SS/HS) Initiative offers a unique opportunity to conduct large-scale, multisite, multilevel program evaluation in the context of a federal environment that places many requirements and constraints on how the grants are conducted and managed. Federal programs stress performance-based outcomes, valid and reliable…

  17. 33 CFR 62.27 - Safe water marks.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Safe water marks. 62.27 Section 62.27 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.27 Safe water marks. Safe water marks indicate that there is...

  18. Developing Safe Schools Partnerships with Law Enforcement

    ERIC Educational Resources Information Center

    Rosiak, John

    2009-01-01

    Safe schools are the concern of communities throughout the world. If a school is safe, and if children feel safe, students "are better able to learn. But what are the steps to make" this happen? First, it is important to understand the problem: What are the threats to school safety? These include crime-related behaviors that find their way to…

  19. Boundary layers in centrifugal compressors. [application of boundary layer theory to compressor design

    NASA Technical Reports Server (NTRS)

    Dean, R. C., Jr.

    1974-01-01

    The utility of boundary-layer theory in the design of centrifugal compressors is demonstrated. Boundary-layer development in the diffuser entry region is shown to be important to stage efficiency. The result of an earnest attempt to analyze this boundary layer with the best tools available is displayed. Acceptable prediction accuracy was not achieved. The inaccuracy of boundary-layer analysis in this case would result in stage efficiency prediction as much as four points low. Fluid dynamic reasons for analysis failure are discussed with support from flow data. Empirical correlations used today to circumnavigate the weakness of the theory are illustrated.

  20. Study of boundary-layer transition using transonic-cone preston tube data

    NASA Technical Reports Server (NTRS)

    Reed, T. D.; Moretti, P. M.

    1980-01-01

    The laminar boundary layer on a 10 degree cone in a transonic wind tunnel was studied. The inviscid flow and boundary layer development were simulated by computer programs. The effects of pitch and yaw angles on the boundary layer were examined. Preston-tube data, taken on the boundary-layer-transition cone in the NASA Ames 11 ft transonic wind tunnel, were used to develope a correlation which relates the measurements to theoretical values of laminar skin friction. The recommended correlation is based on a compressible form of the classical law-of-the-wall. The computer codes successfully simulates the laminar boundary layer for near-zero pitch and yaw angles. However, in cases of significant pitch and/or yaw angles, the flow is three dimensional and the boundary layer computer code used here cannot provide a satisfactory model. The skin-friction correlation is thought to be valid for body geometries other than cones.

  1. Interacting effects of strengthening and twin boundary migration in nanotwinned materials

    NASA Astrophysics Data System (ADS)

    Joshi, Kartikey; Joshi, Shailendra P.

    Twin boundaries play a governing role in the mechanical characteristics of nanotwinned materials. They act as yield strengthening agents by offering resistance to non-coplanar dislocation slip. Twin boundary migration may cause yield softening while also enhancing the strain hardening response. In this work, we investigate the interaction between strengthening and twin boundary migration mechanisms by developing a length-scale dependent crystal plasticity framework for face-centered-cubic nanotwinned materials. The crystal plasticity model incorporates strengthening mechanisms due to dislocation pile-up via slip and slip-rate gradients and twin boundary migration via source-based twin partial nucleation and lattice dislocation-twin boundary interaction. The coupled effect of the load orientation and initial twin size on the speed of twin boundary is discussed and an expression for the same is proposed in terms of relevant material parameters. The efficacy of finite element simulations and the analytical expression in predicting evolution of nanotwinned microstructures comprising size and spatial distributions of twins is demonstrated.

  2. Impacts of Lateral Boundary Conditions on US Ozone ...

    EPA Pesticide Factsheets

    Chemical boundary conditions are a key input to regional-scale photochemical models. In this study, we perform annual simulations over North America with chemical boundary conditions prepared from two global models (GEOS-CHEM and Hemispheric CMAQ). Results indicate that the impacts of different boundary conditions on ozone can be significant throughout the year. The National Exposure Research Laboratory (NERL) Computational Exposure Division (CED) develops and evaluates data, decision-support tools, and models to be applied to media-specific or receptor-specific problem areas. CED uses modeling-based approaches to characterize exposures, evaluate fate and transport, and support environmental diagnostics/forensics with input from multiple data sources. It also develops media- and receptor-specific models, process models, and decision support tools for use both within and outside of EPA.

  3. Boundary layer and fundamental problems of hydrodynamics (compatibility of a logarithmic velocity profile in a turbulent boundary layer with the experience values)

    NASA Astrophysics Data System (ADS)

    Zaryankin, A. E.

    2017-11-01

    The compatibility of the semiempirical turbulence theory of L. Prandtl with the actual flow pattern in a turbulent boundary layer is considered in this article, and the final calculation results of the boundary layer is analyzed based on the mentioned theory. It shows that accepted additional conditions and relationships, which integrate the differential equation of L. Prandtl, associating the turbulent stresses in the boundary layer with the transverse velocity gradient, are fulfilled only in the near-wall region where the mentioned equation loses meaning and are inconsistent with the physical meaning on the main part of integration. It is noted that an introduced concept about the presence of a laminar sublayer between the wall and the turbulent boundary layer is the way of making of a physical meaning to the logarithmic velocity profile, and can be defined as adjustment of the actual flow to the formula that is inconsistent with the actual boundary conditions. It shows that coincidence of the experimental data with the actual logarithmic profile is obtained as a result of the use of not particular physical value, as an argument, but function of this value.

  4. Safe abortion information hotlines: An effective strategy for increasing women's access to safe abortions in Latin America.

    PubMed

    Drovetta, Raquel Irene

    2015-05-01

    This paper describes the implementation of five Safe Abortion Information Hotlines (SAIH), a strategy developed by feminist collectives in a growing number of countries where abortion is legally restricted and unsafe. These hotlines have a range of goals and take different forms, but they all offer information by telephone to women about how to terminate a pregnancy using misoprostol. The paper is based on a qualitative study carried out in 2012-2014 of the structure, goals and experiences of hotlines in five Latin American countries: Argentina, Chile, Ecuador, Peru and Venezuela. The methodology included participatory observation of activities of the SAIH, and in-depth interviews with feminist activists who offer these services and with 14 women who used information provided by these hotlines to induce their own abortions. The findings are also based on a review of materials obtained from the five hotline collectives involved: documents and reports, social media posts, and details of public demonstrations and statements. These hotlines have had a positive impact on access to safe abortions for women whom they help. Providing these services requires knowledge and information skills, but little infrastructure. They have the potential to reduce the risk to women's health and lives of unsafe abortion, and should be promoted as part of public health policy, not only in Latin America but also other countries. Additionally, they promote women's autonomy and right to decide whether to continue or terminate a pregnancy. Copyright © 2015. Published by Elsevier Ltd.

  5. Air Quality Inside Police Drug Safes and Drug Storage Areas.

    PubMed

    Doran, Gregory S; Deans, Ralph; De Filippis, Carlo; Kostakis, Chris; Howitt, Julia A

    2018-06-01

    Storage of drug-based evidence inside sealed safes may allow chemical vapors to accumulate, creating concerns of drug exposure by inhalation, or the possibility of cross-contamination of drug evidence. Air samples were taken from inside eight drug safes and one small storage room at nine city and country police stations, as well as a large centralized drug evidence storage vault, in New South Wales (NSW), Australia. Sorbent tubes containing charcoal were used to determine whether any drug residues could be detected in the air, and to identify the types of chemicals present. Carbon traps were extracted and analyzed by LC-MS-MS for a suite of 22 licit and illicit drug residues and 2 metabolites. Carbon traps and SPME fibers were also analyzed by GC-MS for general volatile organic compound (VOC) residues. No detectable drug residues, either as airborne dust or vapor, were found in the safes, the storage room or the large central repository vault. No drugs were detected in any of the 34 urine samples collected at 8 of the 10 sampling locations, while only one of the five hair samples was positive for cocaine (9 pg/mg) provided by police exhibit officers at 3 of the 10 sampling locations. VOC analysis identified a variety of solvents associated with drug manufacture, plasticisers, personal care products and volatiles associated with plants such as cannabis. The results indicate that strong chemical odours emanating from drug safes are unlikely to be drug residues due to low volatility of drugs, and are more likely VOCs associated with their manufacture or from plant growing operations. Consideration should be given to the quality of air flow in rooms in which safes are housed and the use of air filtering inside safes to reduce the likelihood of VOC accumulation, and therefore the risk of human exposure.

  6. Safe haven laws as crime control theater.

    PubMed

    Hammond, Michelle; Miller, Monica K; Griffin, Timothy

    2010-07-01

    This article examines safe haven laws, which allow parents to legally abandon their infants. The main objective is to determine whether safe haven laws fit the criteria of crime control theater, a term used to describe public policies that produce the appearance, but not the effect, of crime control, and as such are essentially socially constructed "solutions" to socially constructed crime "problems." The analysis will apply the principles of crime control theater to safe haven laws. Specifically, the term crime control theater applies to laws that are reactionary responses to perceived criminal threats and are often widely supported as a way to address the crime in question. Such laws are attractive because they appeal to mythic narratives (i.e., saving an innocent child from a predator); however they are likely ineffective due to the complexity of the crime. These laws can have deleterious effects when policymakers make false claims of success and stunt public discourse (e.g., drawing attention away from more frequent and preventable crimes). This analysis applies these criteria to safe haven laws to determine whether such laws can be classified as crime control theater. Many qualities inherent to crime control theater are present in safe haven laws. For example, the laws are highly publicized, their intentions lack moral ambiguity, rare cases of success legitimize law enforcement and other agencies, and they appeal to the public sense of responsibility in preventing crime. Yet the goal of saving infant lives may be unattainable. These qualities make the effectiveness of the laws questionable and suggest they may be counterproductive. This analysis determined that safe haven laws are socially constructed solutions to the socially constructed problem of child abandonment. Safe haven laws are appropriately classified as crime control theater. It is imperative that further research be conducted to examine the effectiveness and collateral effects of safe haven laws

  7. Grain boundary engineering: fatigue fracture

    NASA Astrophysics Data System (ADS)

    Das, Arpan

    2017-04-01

    Grain boundary engineering has revealed significant enhancement of material properties by modifying the populations and connectivity of different types of grain boundaries within the polycrystals. The character and connectivity of grain boundaries in polycrystalline microstructures control the corrosion and mechanical behaviour of materials. A comprehensive review of the previous researches has been carried out to understand this philosophy. Present research thoroughly explores the effect of total strain amplitude on phase transformation, fatigue fracture features, grain size, annealing twinning, different grain connectivity and grain boundary network after strain controlled low cycle fatigue deformation of austenitic stainless steel under ambient temperature. Electron backscatter diffraction technique has been used extensively to investigate the grain boundary characteristics and morphologies. The nominal variation of strain amplitude through cyclic plastic deformation is quantitatively demonstrated completely in connection with the grain boundary microstructure and fractographic features to reveal the mechanism of fatigue fracture of polycrystalline austenite. The extent of boundary modifications has been found to be a function of the number of applied loading cycles and strain amplitudes. It is also investigated that cyclic plasticity induced martensitic transformation strongly influences grain boundary characteristics and modifications of the material's microstructure/microtexture as a function of strain amplitudes. The experimental results presented here suggest a path to grain boundary engineering during fatigue fracture of austenite polycrystals.

  8. Open Heisenberg chain under boundary fields: A magnonic logic gate

    NASA Astrophysics Data System (ADS)

    Landi, Gabriel T.; Karevski, Dragi

    2015-05-01

    We study the spin transport in the quantum Heisenberg spin chain subject to boundary magnetic fields and driven out of equilibrium by Lindblad dissipators. An exact solution is given in terms of matrix product states, which allows us to calculate exactly the spin current for any chain size. It is found that the system undergoes a discontinuous spin-valve-like quantum phase transition from ballistic to subdiffusive spin current, depending on the value of the boundary fields. Thus, the chain behaves as an extremely sensitive magnonic logic gate operating with the boundary fields as the base element.

  9. The impact of a school-based safe water and hygiene programme on knowledge and practices of students and their parents: Nyanza Province, western Kenya, 2006

    PubMed Central

    O'REILLY, C. E.; FREEMAN, M. C.; RAVANI, M.; MIGELE, J.; MWAKI, A.; AYALO, M.; OMBEKI, S.; HOEKSTRA, R. M.; QUICK, R.

    2008-01-01

    SUMMARY Safe drinking water and hygiene are essential to reducing Kenya's diarrhoeal disease burden. A school-based safe water and hygiene intervention in Kenya was evaluated to assess its impact on students' knowledge and parents' adoption of safe water and hygiene practices. We surveyed 390 students from nine schools and their parents at baseline and conducted a final evaluation of 363 students and their parents. From baseline to final evaluation, improvement was seen in students' knowledge of correct water treatment procedure (21–65%, P<0·01) and knowing when to wash their hands. At final evaluation, 14% of parents reported currently treating their water, compared with 6% at baseline (P<0·01). From 2004 to 2005, school absenteeism in the September–November term decreased in nine project schools by 35% and increased in nine neighbouring comparison schools by 5%. This novel programme shows promise for reducing school absenteeism and promoting water and hygiene interventions in the home. PMID:17306051

  10. Defining a Safe Operating Space for inland recreational fisheries

    USGS Publications Warehouse

    Carpenter, Stephen R.; Brock, William A.; Hansen, Gretchen J. A.; Hansen, Jonathan F.; Hennessy, Joseph M.; Isermann, Daniel A.; Pedersen, Eric J.; Perales, K. Martin; Rypel, Andrew L.; Sass, Greg G.; Tunney, Tyler D.; Vander Zanden, M. Jake

    2017-01-01

    The Safe Operating Space (SOS) of a recreational fishery is the multidimensional region defined by levels of harvest, angler effort, habitat, predation and other factors in which the fishery is sustainable into the future. SOS boundaries exhibit trade-offs such that decreases in harvest can compensate to some degree for losses of habitat, increases in predation and increasing value of fishing time to anglers. Conversely, high levels of harvest can be sustained if habitat is intact, predation is low, and value of fishing effort is moderate. The SOS approach recognizes limits in several dimensions: at overly high levels of harvest, habitat loss, predation, or value of fishing effort, the stock falls to a low equilibrium biomass. Recreational fisheries managers can influence harvest and perhaps predation, but they must cope with trends that are beyond their control such as changes in climate, loss of aquatic habitat or social factors that affect the value of fishing effort for anglers. The SOS illustrates opportunities to manage harvest or predation to maintain quality fisheries in the presence of trends in climate, social preferences or other factors that are not manageable.

  11. Influence of the lower boundary in lysimeter observations

    NASA Astrophysics Data System (ADS)

    Weller, Ulrich; Richter, Katja; Gubis, Jozef; Vogel, Hans-Jörg

    2014-05-01

    Lysimeters are a valuable tool to study the water household in soils under close to natural conditions. One major drawback is that they are cut off at the lower boundary. This influences strongly the percolation of water. As long as water is leaching down in the soil, it is stagnating at the lower boundary until saturated conditions are reached and the water can percolate through the gravel filter, and under unsaturated conditions there is no flow at all at the lower boundary. In natural soils the water potential at the same depth differs considerably from the regime in a lysimeter. If the depth of the soil or the soil forming substrate is deep enough, the lower boundary is at the potential that allows the percolation of the long term mean of percolation. In other situations, a water table may influence the matric potential in the natural soil, or a less permeable layer may impede free drainage. In all these situations the matric potential at the depth of the lower boundary of the lysimeter will differ substantially in the natural soil. The latest generation of lysimeter therefore has a controlled lower boundary. The matric potential can be actively adjusted to a desired value over a broad range. Most applications connect the suction in the lysimeter to a reference value obtained in the field at the same depth in order to mimic the correct distribution of the soil water. In this presentation we demonstrate the long term influence of the different lower boundary regimes on percolation and evaporation of water based on soil physical models, and we show first field data on the practical implementations with several months of observations.

  12. Role of Grain Boundaries under Long-Time Radiation

    NASA Astrophysics Data System (ADS)

    Zhu, Yichao; Luo, Jing; Guo, Xu; Xiang, Yang; Chapman, Stephen Jonathan

    2018-06-01

    Materials containing a high proportion of grain boundaries offer significant potential for the development of radiation-resistant structural materials. However, a proper understanding of the connection between the radiation-induced microstructural behavior of a grain boundary and its impact at long natural time scales is still missing. In this Letter, point defect absorption at interfaces is summarized by a jump Robin-type condition at a coarse-grained level, wherein the role of interface microstructure is effectively taken into account. Then a concise formula linking the sink strength of a polycrystalline aggregate with its grain size is introduced and is well compared with experimental observation. Based on the derived model, a coarse-grained formulation incorporating the coupled evolution of grain boundaries and point defects is proposed, so as to underpin the study of long-time morphological evolution of grains induced by irradiation. Our simulation results suggest that the presence of point defect sources within a grain further accelerates its shrinking process, and radiation tends to trigger the extension of twin boundary sections.

  13. Direct detection of Mycobacterium tuberculosis rifampin resistance in bio-safe stained sputum smears

    PubMed Central

    Lavania, Surabhi; Anthwal, Divya; Bhalla, Manpreet; Singh, Nagendra; Haldar, Sagarika; Tyagi, Jaya Sivaswami

    2017-01-01

    Direct smear microscopy of sputum forms the mainstay of TB diagnosis in resource-limited settings. Stained sputum smear slides can serve as a ready-made resource to transport sputum for molecular drug susceptibility testing. However, bio-safety is a major concern during transport of sputum/stained slides and for laboratory workers engaged in processing Mycobacterium tuberculosis infected sputum specimens. In this study, a bio-safe USP (Universal Sample Processing) concentration-based sputum processing method (Bio-safe method) was assessed on 87 M. tuberculosis culture positive sputum samples. Samples were processed for Ziehl-Neelsen (ZN) smear, liquid culture and DNA isolation. DNA isolated directly from sputum was subjected to an IS6110 PCR assay. Both sputum DNA and DNA extracted from bio-safe ZN concentrated smear slides were subjected to rpoB PCR and simultaneously assessed by DNA sequencing for determining rifampin (RIF) resistance. All sputum samples were rendered sterile by Bio-safe method. Bio-safe smears exhibited a 5% increment in positivity over direct smear with a 14% increment in smear grade status. All samples were positive for IS6110 and rpoB PCR. Thirty four percent samples were RIF resistant by rpoB PCR product sequencing. A 100% concordance (κ value = 1) was obtained between sequencing results derived from bio-safe smear slides and bio-safe sputum. This study demonstrates that Bio-safe method can address safety issues associated with sputum processing, provide an efficient alternative to sample transport in the form of bio-safe stained concentrated smear slides and can also provide information on drug (RIF) resistance by direct DNA sequencing. PMID:29216262

  14. Using Medications Safely

    MedlinePlus

    ... health systems play an important role in preventing medication errors. To make sure you use medicines safely and effectively, ASHP recommends that you: Keep a list of all medications that you take (prescribed drugs, nonprescription medicines, herbal ...

  15. Optimal Growth in Hypersonic Boundary Layers

    NASA Technical Reports Server (NTRS)

    Paredes, Pedro; Choudhari, Meelan M.; Li, Fei; Chang, Chau-Lyan

    2016-01-01

    The linear form of the parabolized linear stability equations is used in a variational approach to extend the previous body of results for the optimal, nonmodal disturbance growth in boundary-layer flows. This paper investigates the optimal growth characteristics in the hypersonic Mach number regime without any high-enthalpy effects. The influence of wall cooling is studied, with particular emphasis on the role of the initial disturbance location and the value of the spanwise wave number that leads to the maximum energy growth up to a specified location. Unlike previous predictions that used a basic state obtained from a self-similar solution to the boundary-layer equations, mean flow solutions based on the full Navier-Stokes equations are used in select cases to help account for the viscous- inviscid interaction near the leading edge of the plate and for the weak shock wave emanating from that region. Using the full Navier-Stokes mean flow is shown to result in further reduction with Mach number in the magnitude of optimal growth relative to the predictions based on the self-similar approximation to the base flow.

  16. Corrected simulations for one-dimensional diffusion processes with naturally occurring boundaries.

    PubMed

    Shafiey, Hassan; Gan, Xinjun; Waxman, David

    2017-11-01

    To simulate a diffusion process, a usual approach is to discretize the time in the associated stochastic differential equation. This is the approach used in the Euler method. In the present work we consider a one-dimensional diffusion process where the terms occurring, within the stochastic differential equation, prevent the process entering a region. The outcome is a naturally occurring boundary (which may be absorbing or reflecting). A complication occurs in a simulation of this situation. The term involving a random variable, within the discretized stochastic differential equation, may take a trajectory across the boundary into a "forbidden region." The naive way of dealing with this problem, which we refer to as the "standard" approach, is simply to reset the trajectory to the boundary, based on the argument that crossing the boundary actually signifies achieving the boundary. In this work we show, within the framework of the Euler method, that such resetting introduces a spurious force into the original diffusion process. This force may have a significant influence on trajectories that come close to a boundary. We propose a corrected numerical scheme, for simulating one-dimensional diffusion processes with naturally occurring boundaries. This involves correcting the standard approach, so that an exact property of the diffusion process is precisely respected. As a consequence, the proposed scheme does not introduce a spurious force into the dynamics. We present numerical test cases, based on exactly soluble one-dimensional problems with one or two boundaries, which suggest that, for a given value of the discrete time step, the proposed scheme leads to substantially more accurate results than the standard approach. Alternatively, the standard approach needs considerably more computation time to obtain a comparable level of accuracy to the proposed scheme, because the standard approach requires a significantly smaller time step.

  17. Corrected simulations for one-dimensional diffusion processes with naturally occurring boundaries

    NASA Astrophysics Data System (ADS)

    Shafiey, Hassan; Gan, Xinjun; Waxman, David

    2017-11-01

    To simulate a diffusion process, a usual approach is to discretize the time in the associated stochastic differential equation. This is the approach used in the Euler method. In the present work we consider a one-dimensional diffusion process where the terms occurring, within the stochastic differential equation, prevent the process entering a region. The outcome is a naturally occurring boundary (which may be absorbing or reflecting). A complication occurs in a simulation of this situation. The term involving a random variable, within the discretized stochastic differential equation, may take a trajectory across the boundary into a "forbidden region." The naive way of dealing with this problem, which we refer to as the "standard" approach, is simply to reset the trajectory to the boundary, based on the argument that crossing the boundary actually signifies achieving the boundary. In this work we show, within the framework of the Euler method, that such resetting introduces a spurious force into the original diffusion process. This force may have a significant influence on trajectories that come close to a boundary. We propose a corrected numerical scheme, for simulating one-dimensional diffusion processes with naturally occurring boundaries. This involves correcting the standard approach, so that an exact property of the diffusion process is precisely respected. As a consequence, the proposed scheme does not introduce a spurious force into the dynamics. We present numerical test cases, based on exactly soluble one-dimensional problems with one or two boundaries, which suggest that, for a given value of the discrete time step, the proposed scheme leads to substantially more accurate results than the standard approach. Alternatively, the standard approach needs considerably more computation time to obtain a comparable level of accuracy to the proposed scheme, because the standard approach requires a significantly smaller time step.

  18. Formulation and Implementation of Inflow/Outflow Boundary Conditions to Simulate Propulsive Effects

    NASA Technical Reports Server (NTRS)

    Rodriguez, David L.; Aftosmis, Michael J.; Nemec, Marian

    2018-01-01

    Boundary conditions appropriate for simulating flow entering or exiting the computational domain to mimic propulsion effects have been implemented in an adaptive Cartesian simulation package. A robust iterative algorithm to control mass flow rate through an outflow boundary surface is presented, along with a formulation to explicitly specify mass flow rate through an inflow boundary surface. The boundary conditions have been applied within a mesh adaptation framework based on the method of adjoint-weighted residuals. This allows for proper adaptive mesh refinement when modeling propulsion systems. The new boundary conditions are demonstrated on several notional propulsion systems operating in flow regimes ranging from low subsonic to hypersonic. The examples show that the prescribed boundary state is more properly imposed as the mesh is refined. The mass-flowrate steering algorithm is shown to be an efficient approach in each example. To demonstrate the boundary conditions on a realistic complex aircraft geometry, two of the new boundary conditions are also applied to a modern low-boom supersonic demonstrator design with multiple flow inlets and outlets.

  19. Discrete transparent boundary conditions for the mixed KDV-BBM equation

    NASA Astrophysics Data System (ADS)

    Besse, Christophe; Noble, Pascal; Sanchez, David

    2017-09-01

    In this paper, we consider artificial boundary conditions for the linearized mixed Korteweg-de Vries (KDV) and Benjamin-Bona-Mahoney (BBM) equation which models water waves in the small amplitude, large wavelength regime. Continuous (respectively discrete) artificial boundary conditions involve non local operators in time which in turn requires to compute time convolutions and invert the Laplace transform of an analytic function (respectively the Z-transform of an holomorphic function). In this paper, we propose a new, stable and fairly general strategy to carry out this crucial step in the design of transparent boundary conditions. For large time simulations, we also introduce a methodology based on the asymptotic expansion of coefficients involved in exact direct transparent boundary conditions. We illustrate the accuracy of our methods for Gaussian and wave packets initial data.

  20. 75 FR 12569 - Notice of Lodging of Consent Decree Under the Safe Drinking Water Act

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-16

    ... DEPARTMENT OF JUSTICE Notice of Lodging of Consent Decree Under the Safe Drinking Water Act..., pursuant to Section 1414(b) of the Safe Drinking Water Act (``SDWA''), 42 U.S.C. 300G-3(b), based upon Evenhouse's alleged violations of the SDWA and regulations thereunder at two separate community water...

  1. Between demarcation and discretion: The medical-administrative boundary as a locus of safety in high-volume organisational routines.

    PubMed

    Grant, Suzanne; Guthrie, Bruce

    2018-04-01

    Patient safety is an increasing concern for health systems internationally. The majority of administrative work in UK general practice takes place in the context of organisational routines such as repeat prescribing and test results handling, where high workloads and increased clinician dependency on administrative staff have been identified as an emerging safety issue. Despite this trend, most research to date has focused on the redistribution of the clinical workload between doctors, nurses and allied health professionals within individual care settings. Drawing on Strauss's negotiated order perspective, we examine ethnographically the achievement of safety across the medical-administrative boundary in key high-volume routines in UK general practice. We focus on two main issues. First, GPs engaged in strategies of demarcation by defining receptionist work as routine, unspecialised and dependent upon GP clinical knowledge and oversight as the safety net to deal with complexity and risk. Receptionists consented to this 'social closure' when describing their role, thus reinforcing the underlying inter-occupational relationship of medical domination. Second, in everyday practice, GPs and receptionists engaged in informal boundary-blurring to safely accommodate the complexity of everyday high-volume routine work. This comprised additional informal discretionary spaces for receptionist decision-making and action that went beyond the routine safety work formally assigned to them. New restratified intra-occupational hierarchies were also being created between receptionists based on the complexity of the safety work that they were authorised to do at practice level, with specialised roles constituting a new form of administrative 'professional project'. The article advances negotiated order theory by providing an in-depth examination of the ways in which medical-administrative boundary-making and boundary-blurring constitute distinct modes of safety in high

  2. First-principles study of the effect of phosphorus on nickel grain boundary

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

    Liu, Wenguan; Ren, Cuilan; Han, Han, E-mail: hanhan@sinap.ac.cn, E-mail: xuhongjie@sinap.ac.cn

    2014-01-28

    Based on first-principles quantum-mechanical calculations, the impurity-dopant effects of phosphorus on Σ5(012) symmetrical tilt grain boundary in nickel have been studied. The calculated binding energy suggests that phosphorus has a strong tendency to segregate to the grain boundary. Phosphorus forms strong and covalent-like bonding with nickel, which is beneficial to the grain boundary cohesion. However, a too high phosphorus content can result in a thin and fragile zone in the grain boundary, due to the repulsion between phosphorus atoms. As the concentration of phosphorus increases, the strength of the grain boundary increases first and then decreases. Obviously, there exists anmore » optimum concentration for phosphorus segregation, which is consistent with observed segregation behaviors of phosphorus in the grain boundary of nickel. This work is very helpful to understand the comprehensive effects of phosphorus.« less

  3. Boundaries & adolescents in residental teatment settings: what clinicians need to know.

    PubMed

    Bunner, Karen; Yonge, Olive

    2006-09-01

    Working with adolescents in psychiatric treatment settings poses unique challenges related to boundaries. Staff are typically from a range of disciplines, and some are from nonregulated professions. Three potential boundary-crossing areas are touching, gift giving, and self-disclosure. To enhance quality of care, staff needs an orientation aimed at boundary education, including the concepts of transference and countertransference; an atmosphere of safety to discuss their observations of themselves and others; to be willing to provide feedback; and a sound knowledge base of adolescent growth and development.

  4. The dependence of carbide morphology on grain boundary character in the highly twinned Alloy 690

    NASA Astrophysics Data System (ADS)

    Li, Hui; Xia, Shuang; Zhou, Bangxin; Chen, Wenjue; Hu, Changliang

    2010-04-01

    The dependence of morphology of grain boundary carbides on grain boundary character in Alloy 690 (Ni-30Cr-10Fe, mass fraction, %) with high fraction of low Σ coincidence site lattice (CSL) grain boundaries was investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Some of the surface grains were removed by means of deep etching. It was observed that carbides grow dendritically at grain boundaries. The carbide bars observed near incoherent twin boundaries and twin related Σ9 grain boundaries are actually secondary dendrites of the carbides on these boundaries. Higher order dendrites could be observed on random grain boundaries, however, no bar-like dendrites were observed near Σ27 grain boundaries and random grain boundaries. The morphology difference of carbides precipitated at grain boundaries with different characters is discussed based on the experimental results in this paper.

  5. Acid–base chemical reaction model for nucleation rates in the polluted atmospheric boundary layer

    PubMed Central

    Chen, Modi; Titcombe, Mari; Jiang, Jingkun; Jen, Coty; Kuang, Chongai; Fischer, Marc L.; Eisele, Fred L.; Siepmann, J. Ilja; Hanson, David R.; Zhao, Jun; McMurry, Peter H.

    2012-01-01

    Climate models show that particles formed by nucleation can affect cloud cover and, therefore, the earth's radiation budget. Measurements worldwide show that nucleation rates in the atmospheric boundary layer are positively correlated with concentrations of sulfuric acid vapor. However, current nucleation theories do not correctly predict either the observed nucleation rates or their functional dependence on sulfuric acid concentrations. This paper develops an alternative approach for modeling nucleation rates, based on a sequence of acid–base reactions. The model uses empirical estimates of sulfuric acid evaporation rates obtained from new measurements of neutral molecular clusters. The model predicts that nucleation rates equal the sulfuric acid vapor collision rate times a prefactor that is less than unity and that depends on the concentrations of basic gaseous compounds and preexisting particles. Predicted nucleation rates and their dependence on sulfuric acid vapor concentrations are in reasonable agreement with measurements from Mexico City and Atlanta. PMID:23091030

  6. Managing drugs safely.

    PubMed

    van den Anker, John N

    2005-02-01

    There is hard data to show that newborn infants are more likely than adults to experience adverse reactions to drugs. Paradoxically, drug-related legislation to ensure safe and effective drug use in humans neglected neonates until 2002, when the Best Pharmaceuticals Act for Children was signed into law in the USA. The situation for neonates should now catch up with that for adults and neonates will be prescribed more licensed drugs in the near future. If we are to be able to analyze the underlying system errors to improve the safe use of drugs in the studied patient population, reporting of adverse drug events and reactions needs to happen in a blame free environment. In addition, computerized physician order entry will certainly further improve the current situation by preventing errors in ordering, transcribing, verifying, and transmitting medication orders.

  7. Evidence of van Hove singularities in ordered grain boundaries of graphene.

    PubMed

    Ma, Chuanxu; Sun, Haifeng; Zhao, Yeliang; Li, Bin; Li, Qunxiang; Zhao, Aidi; Wang, Xiaoping; Luo, Yi; Yang, Jinlong; Wang, Bing; Hou, J G

    2014-06-06

    It has long been under debate whether the electron transport performance of graphene could be enhanced by the possible occurrence of van Hove singularities in grain boundaries. Here, we provide direct experimental evidence to confirm the existence of van Hove singularity states close to the Fermi energy in certain ordered grain boundaries using scanning tunneling microscopy. The intrinsic atomic and electronic structures of two ordered grain boundaries, one with alternative pentagon and heptagon rings and the other with alternative pentagon pair and octagon rings, are determined. It is firmly verified that the carrier concentration and, thus, the conductance around ordered grain boundaries can be significantly enhanced by the van Hove singularity states. This finding strongly suggests that a graphene nanoribbon with a properly embedded ordered grain boundary can be a promising structure to improve the performance of graphene-based electronic devices.

  8. Correlation between grain boundary misorientation and M{sub 23}C{sub 6} precipitation behaviors in a wrought Ni-based superalloy

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

    Tang, Bin, E-mail: toby198489@163.com; Jiang, Li; Hu, Rui

    2013-04-15

    The correlation between the grain boundary misorientation and the precipitation behaviors of intergranular M{sub 23}C{sub 6} carbides in a wrought Ni–Cr–W superalloy was investigated by using the electron backscattered diffraction (EBSD) technique. It was observed that the grain boundaries with a misorientation angle less than 20°, as well as all coincidence site lattice (CSL) boundaries, are immune to precipitation of the M{sub 23}C{sub 6} carbides; in contrast, the random high-angle grain boundaries with a misorientation angle of 20°–40° provide preferential precipitation sites of the M{sub 23}C{sub 6} carbides at the random high-angle grain boundaries with a higher misorientation angle ofmore » 55°–60°/[2 2 3] turn to retard precipitation of M{sub 23}C{sub 6} carbides owing to their nature like the Σ3 grain boundaries and retard the precipitation of M{sub 23}C{sub 6} carbides. The low-angle and certain random grain boundary segments induced by twins were found to interrupt the precipitation of the M{sub 23}C{sub 6} carbides along the high-angle grain boundaries. - Highlights: ► The low angle grain boundaries and CSL boundaries are immune to precipitation. ► M23C6 precipitate preferentially at random grain boundaries within 20°–40°. ► Some certain random grain boundary segments interrupt M23C6 precipitation.« less

  9. Study of fail-safe abort system for an actively cooled hypersonic aircraft, volume 2

    NASA Technical Reports Server (NTRS)

    Peeples, M. E.; Herring, R. L.

    1976-01-01

    Conceptual designs of a fail-safe abort system for hydrogen fueled actively cooled high speed aircraft are examined. The fail-safe concept depends on basically three factors: (1) a reliable method of detecting a failure or malfunction in the active cooling system, (2) the optimization of abort trajectories which minimize the descent heat load to the aircraft, and (3) fail-safe thermostructural concepts to minimize both the weight and the maximum temperature the structure will reach during descent. These factors are examined and promising approaches are evaluated based on weight, reliability, ease of manufacture and cost.

  10. Predicting boundary shear stress and sediment transport over bed forms

    USGS Publications Warehouse

    McLean, S.R.; Wolfe, S.R.; Nelson, J.M.

    1999-01-01

    To estimate bed-load sediment transport rates in flows over bed forms such as ripples and dunes, spatially averaged velocity profiles are frequently used to predict mean boundary shear stress. However, such averaging obscures the complex, nonlinear interaction of wake decay, boundary-layer development, and topographically induced acceleration downstream of flow separation and often leads to inaccurate estimates of boundary stress, particularly skin friction, which is critically important in predicting bed-load transport rates. This paper presents an alternative methodology for predicting skin friction over 2D bed forms. The approach is based on combining the equations describing the mechanics of the internal boundary layer with semiempirical structure functions to predict the velocity at the crest of a bedform, where the flow is most similar to a uniform boundary layer. Significantly, the methodology is directed toward making specific predictions only at the bed-form crest, and as a result it avoids the difficulty and questionable validity of spatial averaging. The model provides an accurate estimate of the skin friction at the crest where transport rates are highest. Simple geometric constraints can be used to derive the mean transport rates as long as bed load is dominant.To estimate bed-load sediment transport rates in flows over bed forms such as ripples and dunes, spatially averaged velocity profiles are frequently used to predict mean boundary shear stress. However, such averaging obscures the complex, nonlinear interaction of wake decay, boundary-layer development, and topographically induced acceleration downstream of flow separation and often leads to inaccurate estimates of boundary stress, particularly skin friction, which is critically important in predicting bed-load transport rates. This paper presents an alternative methodology for predicting skin friction over 2D bed forms. The approach is based on combining the equations describing the mechanics of

  11. 29 CFR 1919.29 - Limitations on safe working loads and proof loads.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) GEAR CERTIFICATION Certification of Vessels: Tests and Proof... pertinent limitations based on stability and/or on structural competence at particular radii. Safe working...

  12. 29 CFR 1919.29 - Limitations on safe working loads and proof loads.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) GEAR CERTIFICATION Certification of Vessels: Tests and Proof... pertinent limitations based on stability and/or on structural competence at particular radii. Safe working...

  13. 29 CFR 1919.29 - Limitations on safe working loads and proof loads.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) GEAR CERTIFICATION Certification of Vessels: Tests and Proof... pertinent limitations based on stability and/or on structural competence at particular radii. Safe working...

  14. 29 CFR 1919.29 - Limitations on safe working loads and proof loads.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) GEAR CERTIFICATION Certification of Vessels: Tests and Proof... pertinent limitations based on stability and/or on structural competence at particular radii. Safe working...

  15. 29 CFR 1919.29 - Limitations on safe working loads and proof loads.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) GEAR CERTIFICATION Certification of Vessels: Tests and Proof... pertinent limitations based on stability and/or on structural competence at particular radii. Safe working...

  16. Galilean-invariant algorithm coupling immersed moving boundary conditions and Lees-Edwards boundary conditions

    NASA Astrophysics Data System (ADS)

    Zhou, Guofeng; Wang, Limin; Wang, Xiaowei; Ge, Wei

    2011-12-01

    Many investigators have coupled the Lees-Edwards boundary conditions (LEBCs) and suspension methods in the framework of the lattice Boltzmann method to study the pure bulk properties of particle-fluid suspensions. However, these suspension methods are all link-based and are more or less exposed to the disadvantages of violating Galilean invariance. In this paper, we have coupled LEBCs with a node-based suspension method, which is demonstrated to be Galilean invariant in benchmark simulations. We use the coupled algorithm to predict the viscosity of a particle-fluid suspension at very low Reynolds number, and the simulation results are in good agreement with the semiempirical Krieger-Dougherty formula.

  17. Boundary-artifact-free phase retrieval with the transport of intensity equation II: applications to microlens characterization.

    PubMed

    Zuo, Chao; Chen, Qian; Li, Hongru; Qu, Weijuan; Asundi, Anand

    2014-07-28

    Boundary conditions play a crucial role in the solution of the transport of intensity equation (TIE). If not appropriately handled, they can create significant boundary artifacts across the reconstruction result. In a previous paper [Opt. Express 22, 9220 (2014)], we presented a new boundary-artifact-free TIE phase retrieval method with use of discrete cosine transform (DCT). Here we report its experimental investigations with applications to the micro-optics characterization. The experimental setup is based on a tunable lens based 4f system attached to a non-modified inverted bright-field microscope. We establish inhomogeneous Neumann boundary values by placing a rectangular aperture in the intermediate image plane of the microscope. Then the boundary values are applied to solve the TIE with our DCT-based TIE solver. Experimental results on microlenses highlight the importance of boundary conditions that often overlooked in simplified models, and confirm that our approach effectively avoid the boundary error even when objects are located at the image borders. It is further demonstrated that our technique is non-interferometric, accurate, fast, full-field, and flexible, rendering it a promising metrological tool for the micro-optics inspection.

  18. Enhanced ferroelectric polarization and possible morphotrophic phase boundary in PZT-based alloys

    DOE PAGES

    Parker, David S.; Singh, David; McGuire, Michael A.; ...

    2016-05-16

    We present a combined theoretical and experimental study of alloys of the high performance piezoelectric PZT (PbZr 0.5Ti 0.5O 3) with BZnT (BiZn 0.5Ti 0.5O 3) and BZnZr (BiZn 0.5Zr 0.5O 3), focusing on atomic displacements, ferroelectric polarization, and elastic stability. From theory we find that the 75-25 PZT-BZnT alloy has substantially larger cation displacements, and hence ferroelectric polarization than the PZT base material, on the tetragonal side of the phase diagram. We also find a possible morphotrophic phase boundary in this system by comparing displacement patterns and optimized c/a ratios. Elastic stability calculations find the structures to be essentiallymore » stable. Lastly, experiments indicate the feasibility of sample synthesis within this alloy system, although measurements do not find significant polarization, probably due to a large coercive field.« less

  19. Effective Field Theory on Manifolds with Boundary

    NASA Astrophysics Data System (ADS)

    Albert, Benjamin I.

    In the monograph Renormalization and Effective Field Theory, Costello made two major advances in rigorous quantum field theory. Firstly, he gave an inductive position space renormalization procedure for constructing an effective field theory that is based on heat kernel regularization of the propagator. Secondly, he gave a rigorous formulation of quantum gauge theory within effective field theory that makes use of the BV formalism. In this work, we extend Costello's renormalization procedure to a class of manifolds with boundary and make preliminary steps towards extending his formulation of gauge theory to manifolds with boundary. In addition, we reorganize the presentation of the preexisting material, filling in details and strengthening the results.

  20. On Boundaries of the Language of Physics

    NASA Astrophysics Data System (ADS)

    Kvasz, Ladislav

    The aim of the present paper is to outline a method of reconstruction of the historical development of the language of physical theories. We will apply the theory presented in Patterns of Change, Linguistic Innovations in the Development of Classical Mathematics to the analysis of linguistic innovations in physics. Our method is based on a reconstruction of the following potentialities of language: analytical power, expressive power, integrative power, and explanatory power, as well as analytical boundaries and expressive boundaries. One of the results of our reconstruction is a new interpretation of Kant's antinomies of pure reason. If we relate Kant's antinomies to the language, they retain validity.