Known knowns, known unknowns and unknown unknowns in prokaryotic transposition.

Science.gov (United States)

Siguier, Patricia; Gourbeyre, Edith; Chandler, Michael

2017-08-01

Although the phenomenon of transposition has been known for over 60 years, its overarching importance in modifying and streamlining genomes took some time to recognize. In spite of a robust understanding of transposition of some TE, there remain a number of important TE groups with potential high genome impact and unknown transposition mechanisms and yet others, only recently identified by bioinformatics, yet to be formally confirmed as mobile. Here, we point to some areas of limited understanding concerning well established important TE groups with DDE Tpases, to address central gaps in our knowledge of characterised Tn with other types of Tpases and finally, to highlight new potentially mobile DNA species. It is not exhaustive. Examples have been chosen to provide encouragement in the continued exploration of the considerable prokaryotic mobilome especially in light of the current threat to public health posed by the spread of multiple Ab R . Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of alternative styles of risk information on EMF risk perception

DEFF Research Database (Denmark)

Nielsen, Jesper Bo; Elstein, Arthur; Gyrd-Hansen, Dorte

2010-01-01

Risk scenarios characterized by exposures to new technologies with unknown health effects, together with limited appreciation of benefits pose a challenge to risk communication. The present report illustrates this situation through a study of the perceived risk from mobile phones and mobile masts...... radiation from mobile phones and masts. The objective was to study whether different types of information were rated as equally useful, informative, comprehensible, and trustworthy. Moreover, an important issue was whether information would influence risk perception and intended behavior. The conclusion...

Using physics-based pose predictions and free energy perturbation calculations to predict binding poses and relative binding affinities for FXR ligands in the D3R Grand Challenge 2

Science.gov (United States)

Athanasiou, Christina; Vasilakaki, Sofia; Dellis, Dimitris; Cournia, Zoe

2018-01-01

Computer-aided drug design has become an integral part of drug discovery and development in the pharmaceutical and biotechnology industry, and is nowadays extensively used in the lead identification and lead optimization phases. The drug design data resource (D3R) organizes challenges against blinded experimental data to prospectively test computational methodologies as an opportunity for improved methods and algorithms to emerge. We participated in Grand Challenge 2 to predict the crystallographic poses of 36 Farnesoid X Receptor (FXR)-bound ligands and the relative binding affinities for two designated subsets of 18 and 15 FXR-bound ligands. Here, we present our methodology for pose and affinity predictions and its evaluation after the release of the experimental data. For predicting the crystallographic poses, we used docking and physics-based pose prediction methods guided by the binding poses of native ligands. For FXR ligands with known chemotypes in the PDB, we accurately predicted their binding modes, while for those with unknown chemotypes the predictions were more challenging. Our group ranked #1st (based on the median RMSD) out of 46 groups, which submitted complete entries for the binding pose prediction challenge. For the relative binding affinity prediction challenge, we performed free energy perturbation (FEP) calculations coupled with molecular dynamics (MD) simulations. FEP/MD calculations displayed a high success rate in identifying compounds with better or worse binding affinity than the reference (parent) compound. Our studies suggest that when ligands with chemical precedent are available in the literature, binding pose predictions using docking and physics-based methods are reliable; however, predictions are challenging for ligands with completely unknown chemotypes. We also show that FEP/MD calculations hold predictive value and can nowadays be used in a high throughput mode in a lead optimization project provided that crystal structures of

Hg-contaminated terrestrial spiders pose a potential risk to songbirds at Caddo Lake (Texas/Louisiana, USA).

Science.gov (United States)

Gann, Gretchen L; Powell, Cleveland H; Chumchal, Matthew M; Drenner, Ray W

2015-02-01

Methylmercury (MeHg) is an environmental contaminant that can have adverse effects on wildlife. Because MeHg is produced by bacteria in aquatic ecosystems, studies of MeHg contamination of food webs historically have focused on aquatic organisms. However, recent studies have shown that terrestrial organisms such as songbirds can be contaminated with MeHg by feeding on MeHg-contaminated spiders. In the present study, the authors examined the risk that MeHg-contaminated terrestrial long-jawed orb weaver spiders (Tetragnatha sp.) pose to songbirds at Caddo Lake (Texas/Louisiana, USA). Methylmercury concentrations in spiders were significantly different in river, wetland, and open-water habitats. The authors calculated spider-based wildlife values (the minimum spider MeHg concentrations causing physiologically significant doses in consumers) to assess exposure risks for arachnivorous birds. Methylmercury concentrations in spiders exceeded wildlife values for Carolina chickadee (Poecile carolinensis) nestlings, with the highest risk in the river habitat. The present study indicates that MeHg concentrations in terrestrial spiders vary with habitat and can pose a threat to small-bodied nestling birds that consume large amounts of spiders at Caddo Lake. This MeHg threat to songbirds may not be unique to Caddo Lake and may extend throughout the southeastern United States. © 2014 SETAC.

Developing Probabilistic Safety Performance Margins for Unknown and Underappreciated Risks

Science.gov (United States)

Benjamin, Allan; Dezfuli, Homayoon; Everett, Chris

2015-01-01

Probabilistic safety requirements currently formulated or proposed for space systems, nuclear reactor systems, nuclear weapon systems, and other types of systems that have a low-probability potential for high-consequence accidents depend on showing that the probability of such accidents is below a specified safety threshold or goal. Verification of compliance depends heavily upon synthetic modeling techniques such as PRA. To determine whether or not a system meets its probabilistic requirements, it is necessary to consider whether there are significant risks that are not fully considered in the PRA either because they are not known at the time or because their importance is not fully understood. The ultimate objective is to establish a reasonable margin to account for the difference between known risks and actual risks in attempting to validate compliance with a probabilistic safety threshold or goal. In this paper, we examine data accumulated over the past 60 years from the space program, from nuclear reactor experience, from aircraft systems, and from human reliability experience to formulate guidelines for estimating probabilistic margins to account for risks that are initially unknown or underappreciated. The formulation includes a review of the safety literature to identify the principal causes of such risks.

The reduced-risk insecticide azadirachtin poses a toxicological hazard to stingless bee Partamona helleri (Friese, 1900) queens.

Science.gov (United States)

Bernardes, Rodrigo Cupertino; Barbosa, Wagner Faria; Martins, Gustavo Ferreira; Lima, Maria Augusta Pereira

2018-06-01

Large-scale pesticide application poses a major threat to bee biodiversity by causing a decline in bee populations that, in turn, compromises ecosystem maintenance and agricultural productivity. Biopesticides are considered an alternative to synthetic pesticides with a focus on reducing potential detrimental effects to beneficial organisms such as bees. The production of healthy queen stingless bees is essential for the survival and reproduction of hives, although it remains unknown whether biopesticides influence stingless bee reproduction. In the present study, we investigated the effects of the biopesticide azadirachtin on the survival, behavior, morphology, development, and reproduction of queens of the stingless bee Partamona helleri (Friese, 1900). The neonicotinoid imidacloprid was used as a toxic reference standard. Queens were orally exposed in vitro to a contaminated diet (containing azadirachtin and imidacloprid) during development. Azadirachtin resulted in reduced survival, similarly to imidacloprid, altered development time, caused deformations, and reduced the size of the queens' reproductive organs. All of these factors could potentially compromise colony survival. Results from the present study showed azadirachtin posed a toxicological hazard to P. helleri queens. Copyright © 2018 Elsevier Ltd. All rights reserved.

The risks to miners, mines, and the public posed by large seismic events in the gold mining districts of South Africa

CSIR Research Space (South Africa)

Durrheim, RJ

2006-10-01

Full Text Available are incorporating the risks of seismicity in their disaster management plans, and Johannesburg is urged to do likewise. Some buildings are considered vulnerable to damage by large seismic events, posing safety and financial risks....

Review of the Risks Posed to Drinking Water by Man-Made Nanoparticels

DEFF Research Database (Denmark)

Tiede, K.; Westerhoff, P.; Hansen, Steffen Foss

an estimate of the amount of exposure to a range of ENPs from drinking water as well as a relative qualitative risk of exposure to ENPs from drinking water compared to other routes. A range of metal, metal oxide and organic-based ENPs were identified that have the potential to contaminate drinking waters...... drinking waters. In order to address these concerns, the U.K. Drinking Water Inspectorate (DWI) has published a "Review of the risks posed to drinking water by man-made nanoparticles"(DWI 70/2/246). The study, which was funded by the Department for Food and Rural Affairs (Defra), was undertaken by the Food...... (such as ENPs that are produced in large quantities or are used in a free form) were identified and categorised. The classification was based on a categorisation framework to aid exposure assessment of nanomaterials in consumer products. A conservative approach was then used to estimate worst case...

Adaptive relative pose control of spacecraft with model couplings and uncertainties

Science.gov (United States)

Sun, Liang; Zheng, Zewei

2018-02-01

The spacecraft pose tracking control problem for an uncertain pursuer approaching to a space target is researched in this paper. After modeling the nonlinearly coupled dynamics for relative translational and rotational motions between two spacecraft, position tracking and attitude synchronization controllers are developed independently by using a robust adaptive control approach. The unknown kinematic couplings, parametric uncertainties, and bounded external disturbances are handled with adaptive updating laws. It is proved via Lyapunov method that the pose tracking errors converge to zero asymptotically. Spacecraft close-range rendezvous and proximity operations are introduced as an example to validate the effectiveness of the proposed control approach.

An Evidence-Based Review Literature About Risk Indicators and Management of Unknown-Origin Xerostomia

Directory of Open Access Journals (Sweden)

Farzaneh Agha-hosseini

2013-01-01

Full Text Available Objective: This evidence-based article reviews risk indicators and management of unknown-origin xerostomia. Xerostomia and hyposalivation refer to different aspects of dry mouth. Xerostomia is a subjective sensation of dry mouth, whilst hyposalivation is defined as an objective assessment of reduced salivary flow rate. About 30% of the elderly (65 years and older experience xerostomia and hyposalivation. Structural and functional factors, or both may lead to salivary gland dysfunction.Study Selection: The EBM literature search was conducted by using the medical literature database MEDLINE via PubMed and OvidMedline search engines. Results were limited to English language articles (1965 to present including clinical trials (CT, randomized controlled trials (RCT, systematic reviews and review articles. Case control or cohort studies were included for the etiology.Results: Neuropathic etiology such as localized oral alteration of thermal sensations, saliva composition change (for example higher levels of K, Cl, Ca, IgA, amylase, calcium, PTH and cortisol, lower levels of estrogen and progesterone, smaller salivary gland size, and illnesses such as lichen planus, are risk indicators for unknown-origin xerostomia. The management is palliative and preventative. Management of symptoms includes drug administration (systemic secretogogues, saliva substitutes and bile secretion-stimulator, night guard, diet and habit modifications. Other managements may be indicated to treat adverse effects.Conclusion: Neuropathic etiology, saliva composition change, smaller salivary gland size, and illnesses such as oral lichen planus can be suggestive causes for unknown-origin xerostomia. However, longitudinal studies will be important to elucidate the causes of unknown-origin xerostomia.

The interconnected and cross-border nature of risks posed by infectious diseases

Directory of Open Access Journals (Sweden)

Jonathan E. Suk

2014-10-01

Full Text Available Infectious diseases can constitute public health emergencies of international concern when a pathogen arises, acquires new characteristics, or is deliberately released, leading to the potential for loss of human lives as well as societal disruption. A wide range of risk drivers are now known to lead to and/or exacerbate the emergence and spread of infectious disease, including global trade and travel, the overuse of antibiotics, intensive agriculture, climate change, high population densities, and inadequate infrastructures, such as water treatment facilities. Where multiple risk drivers interact, the potential impact of a disease outbreak is amplified. The varying temporal and geographic frequency with which infectious disease events occur adds yet another layer of complexity to the issue. Mitigating the emergence and spread of infectious disease necessitates mapping and prioritising the interdependencies between public health and other sectors. Conversely, during an international public health emergency, significant disruption occurs not only to healthcare systems but also to a potentially wide range of sectors, including trade, tourism, energy, civil protection, transport, agriculture, and so on. At the same time, dealing with a disease outbreak may require a range of critical sectors for support. There is a need to move beyond narrow models of risk to better account for the interdependencies between health and other sectors so as to be able to better mitigate and respond to the risks posed by emerging infectious disease.

Crisis planning to manage risks posed by animal rights extremists.

Science.gov (United States)

Bailey, Matthew R; Rich, Barbara A; Bennett, B Taylor

2010-01-01

Among the multitude of crises that US research institutions may face are those caused by animal rights activists. While most activists opposed to animal research use peaceful and lawful means of expressing their opinions, some extremists resort to illegal methods. Arson, break-ins, and theft with significant property damage at US animal research facilities began in the 1980s. The most troubling trend to develop in the past decade is the targeting of individuals associated with animal research, whether directly or indirectly, and the use of violent scare tactics to intimidate researchers and their families. The National Association for Biomedical Research has a 30-year history of monitoring the animal rights movement and assisting member institutions with crisis situations. In this article we discuss attacks on researchers at their homes, cyber crimes, exploitation of new media formats, infiltration of research facilities, and the targeting of external research stakeholders and business partners. We describe the need for a well-conceived crisis management plan and strong leadership to mitigate crisis situations. Institutions with well-informed leaders and crisis management teams ready to take timely action are best equipped to protect staff, laboratory animals, and research programs. They act on early warnings, provide support for targeted staff, seek legal remedies, thoughtfully control access to research facilities, and identify and enlist new research supporters. We underscore the importance of up-to-date crisis planning so that institutions are not only aware of ongoing risks posed by animal rights extremists but also better prepared to take preemptive action and able to manage those risks successfully.

Animated pose templates for modeling and detecting human actions.

Science.gov (United States)

Yao, Benjamin Z; Nie, Bruce X; Liu, Zicheng; Zhu, Song-Chun

2014-03-01

This paper presents animated pose templates (APTs) for detecting short-term, long-term, and contextual actions from cluttered scenes in videos. Each pose template consists of two components: 1) a shape template with deformable parts represented in an And-node whose appearances are represented by the Histogram of Oriented Gradient (HOG) features, and 2) a motion template specifying the motion of the parts by the Histogram of Optical-Flows (HOF) features. A shape template may have more than one motion template represented by an Or-node. Therefore, each action is defined as a mixture (Or-node) of pose templates in an And-Or tree structure. While this pose template is suitable for detecting short-term action snippets in two to five frames, we extend it in two ways: 1) For long-term actions, we animate the pose templates by adding temporal constraints in a Hidden Markov Model (HMM), and 2) for contextual actions, we treat contextual objects as additional parts of the pose templates and add constraints that encode spatial correlations between parts. To train the model, we manually annotate part locations on several keyframes of each video and cluster them into pose templates using EM. This leaves the unknown parameters for our learning algorithm in two groups: 1) latent variables for the unannotated frames including pose-IDs and part locations, 2) model parameters shared by all training samples such as weights for HOG and HOF features, canonical part locations of each pose, coefficients penalizing pose-transition and part-deformation. To learn these parameters, we introduce a semi-supervised structural SVM algorithm that iterates between two steps: 1) learning (updating) model parameters using labeled data by solving a structural SVM optimization, and 2) imputing missing variables (i.e., detecting actions on unlabeled frames) with parameters learned from the previous step and progressively accepting high-score frames as newly labeled examples. This algorithm belongs to a

Perturbation-Based Regularization for Signal Estimation in Linear Discrete Ill-posed Problems

KAUST Repository

Suliman, Mohamed Abdalla Elhag; Ballal, Tarig; Al-Naffouri, Tareq Y.

2016-01-01

Estimating the values of unknown parameters from corrupted measured data faces a lot of challenges in ill-posed problems. In such problems, many fundamental estimation methods fail to provide a meaningful stabilized solution. In this work, we propose a new regularization approach and a new regularization parameter selection approach for linear least-squares discrete ill-posed problems. The proposed approach is based on enhancing the singular-value structure of the ill-posed model matrix to acquire a better solution. Unlike many other regularization algorithms that seek to minimize the estimated data error, the proposed approach is developed to minimize the mean-squared error of the estimator which is the objective in many typical estimation scenarios. The performance of the proposed approach is demonstrated by applying it to a large set of real-world discrete ill-posed problems. Simulation results demonstrate that the proposed approach outperforms a set of benchmark regularization methods in most cases. In addition, the approach also enjoys the lowest runtime and offers the highest level of robustness amongst all the tested benchmark regularization methods.

Perturbation-Based Regularization for Signal Estimation in Linear Discrete Ill-posed Problems

KAUST Repository

Suliman, Mohamed Abdalla Elhag

2016-11-29

Estimating the values of unknown parameters from corrupted measured data faces a lot of challenges in ill-posed problems. In such problems, many fundamental estimation methods fail to provide a meaningful stabilized solution. In this work, we propose a new regularization approach and a new regularization parameter selection approach for linear least-squares discrete ill-posed problems. The proposed approach is based on enhancing the singular-value structure of the ill-posed model matrix to acquire a better solution. Unlike many other regularization algorithms that seek to minimize the estimated data error, the proposed approach is developed to minimize the mean-squared error of the estimator which is the objective in many typical estimation scenarios. The performance of the proposed approach is demonstrated by applying it to a large set of real-world discrete ill-posed problems. Simulation results demonstrate that the proposed approach outperforms a set of benchmark regularization methods in most cases. In addition, the approach also enjoys the lowest runtime and offers the highest level of robustness amongst all the tested benchmark regularization methods.

Problem Posing

OpenAIRE

Šilhavá, Marie

2009-01-01

This diploma thesis concentrates on problem posing from the students' point of view. Problem posing can be either seen as a teaching method which can be used in the class, or it can be used as a tool for researchers or teachers to assess the level of students' understanding of the topic. In my research, I compare three classes, one mathematics specialist class and two generalist classes, in their ability of problem posing. As an assessment tool it seemed that mathemathics specialists were abl...

Stereovision-based pose and inertia estimation of unknown and uncooperative space objects

Science.gov (United States)

Pesce, Vincenzo; Lavagna, Michèle; Bevilacqua, Riccardo

2017-01-01

Autonomous close proximity operations are an arduous and attractive problem in space mission design. In particular, the estimation of pose, motion and inertia properties of an uncooperative object is a challenging task because of the lack of available a priori information. This paper develops a novel method to estimate the relative position, velocity, angular velocity, attitude and the ratios of the components of the inertia matrix of an uncooperative space object using only stereo-vision measurements. The classical Extended Kalman Filter (EKF) and an Iterated Extended Kalman Filter (IEKF) are used and compared for the estimation procedure. In addition, in order to compute the inertia properties, the ratios of the inertia components are added to the state and a pseudo-measurement equation is considered in the observation model. The relative simplicity of the proposed algorithm could be suitable for an online implementation for real applications. The developed algorithm is validated by numerical simulations in MATLAB using different initial conditions and uncertainty levels. The goal of the simulations is to verify the accuracy and robustness of the proposed estimation algorithm. The obtained results show satisfactory convergence of estimation errors for all the considered quantities. The obtained results, in several simulations, shows some improvements with respect to similar works, which deal with the same problem, present in literature. In addition, a video processing procedure is presented to reconstruct the geometrical properties of a body using cameras. This inertia reconstruction algorithm has been experimentally validated at the ADAMUS (ADvanced Autonomous MUltiple Spacecraft) Lab at the University of Florida. In the future, this different method could be integrated to the inertia ratios estimator to have a complete tool for mass properties recognition.

Reactive Path Planning Approach for Docking Robots in Unknown Environment

Directory of Open Access Journals (Sweden)

Peng Cui

2017-01-01

Full Text Available Autonomous robots need to be recharged and exchange information with the host through docking in the long-distance tasks. Therefore, feasible path is required in the docking process to guide the robot and adjust its pose. However, when there are unknown obstacles in the work area, it becomes difficult to determine the feasible path for docking. This paper presents a reactive path planning approach named Dubins-APF (DAPF to solve the path planning problem for docking in unknown environment with obstacles. In this proposed approach the Dubins curves are combined with the designed obstacle avoidance potential field to plan the feasible path. Firstly, an initial path is planned and followed according to the configurations of the robot and the docking station. Then when the followed path is evaluated to be infeasible, the intermediate configuration is calculated as well as the replanned path based on the obstacle avoidance potential field. The robot will be navigated to the docking station with proper pose eventually via the DAPF approach. The proposed DAPF approach is efficient and does not require the prior knowledge about the environment. Simulation results are given to validate the effectiveness and feasibility of the proposed approach.

Associated risk factors for chronic kidney disease of unknown etiologies in 241 patients.

Science.gov (United States)

Xing, Xuexue; Lu, Jing; Wang, Zheng

2015-04-01

Apart from the well-known etiologies, there are still a high proportion of patients with chronic kidney disease of unknown etiology (CKDu), which has rarely been reported on. In this study, we explored the potential associated risk factors for CKDu and identified those that occur in childhood. 700 patients with CKD we were selected randomly from 4 hospitals in Chengdu and 241 were screened for CKDu. The following clinical information was analyzed: demographic data, life style, personal and family history, nephrotoxic drugs, exposure to poison, allergies, and recurrent respiratory infections in childhood. Among 700 CKD patients, 34.43% (241/700) were CKDu. Of the 241 patients, there were 67.63% (163/241) with at least 1 associated risk factor and 56.44% (92/163) with more than 1. Patients with a personal history of an associated risk factor represented the largest proportion (31.95%, 77/241), while 28.63% (69/241) of the CKDu patients had risk factors appearing in childhood. Logistic regression analysis supported the results. The study demonstrated that most so-called CKDu patients do have an identifiable etiology, and that several associated risk factors contribute to it. Of all the risk factors, age >60 years, nephrotoxic drugs, exposure to poison, and alcohol consumption were the independent significant factors for CKDu. Furthermore, many risk factors that caused kidney injury started in childhood.

Robotic-surgical instrument wrist pose estimation.

Science.gov (United States)

Fabel, Stephan; Baek, Kyungim; Berkelman, Peter

2010-01-01

The Compact Lightweight Surgery Robot from the University of Hawaii includes two teleoperated instruments and one endoscope manipulator which act in accord to perform assisted interventional medicine. The relative positions and orientations of the robotic instruments and endoscope must be known to the teleoperation system so that the directions of the instrument motions can be controlled to correspond closely to the directions of the motions of the master manipulators, as seen by the the endoscope and displayed to the surgeon. If the manipulator bases are mounted in known locations and all manipulator joint variables are known, then the necessary coordinate transformations between the master and slave manipulators can be easily computed. The versatility and ease of use of the system can be increased, however, by allowing the endoscope or instrument manipulator bases to be moved to arbitrary positions and orientations without reinitializing each manipulator or remeasuring their relative positions. The aim of this work is to find the pose of the instrument end effectors using the video image from the endoscope camera. The P3P pose estimation algorithm is used with a Levenberg-Marquardt optimization to ensure convergence. The correct transformations between the master and slave coordinate frames can then be calculated and updated when the bases of the endoscope or instrument manipulators are moved to new, unknown, positions at any time before or during surgical procedures.

What Butterfly Effect? The Contextual Differences in Public Perceptions of the Health Risk Posed by Climate Change

Directory of Open Access Journals (Sweden)

James W. Stoutenborough

2015-08-01

Full Text Available One of the most difficult aspects of persuading the public to support climate change policy is the lack of recognition that climate change will likely have a direct impact on an individual’s life. Anecdotal evidence and arguments within the media suggest that those who are skeptical of climate change are more likely to believe that the negative externalities associated with climate change will be experienced by others, and, therefore, are not a concern to that individual. This project examines public perceptions of the health risk posed by climate change. Using a large national public opinion survey of adults in the United States, respondents were asked to evaluate the health risk for themselves, their community, the United States, and the world. The results suggest that individuals evaluate the risk for each of these contexts differently. Statistical analyses are estimated to identify the determinants of each risk perception to identify their respective differences. The implications of these findings on support for climate change policy are discussed.

Yoga Poses Increase Subjective Energy and State Self-Esteem in Comparison to 'Power Poses'.

Science.gov (United States)

Golec de Zavala, Agnieszka; Lantos, Dorottya; Bowden, Deborah

2017-01-01

Research on beneficial consequences of yoga focuses on the effects of yogic breathing and meditation. Less is known about the psychological effects of performing yoga postures. The present study investigated the effects of yoga poses on subjective sense of energy and self-esteem. The effects of yoga postures were compared to the effects of 'power poses,' which arguably increase the sense of power and self-confidence due to their association with interpersonal dominance (Carney et al., 2010). The study tested the novel prediction that yoga poses, which are not associated with interpersonal dominance but increase bodily energy, would increase the subjective feeling of energy and therefore increase self-esteem compared to 'high power' and 'low power' poses. A two factorial, between participants design was employed. Participants performed either two standing yoga poses with open front of the body ( n = 19), two standing yoga poses with covered front of the body ( n = 22), two expansive, high power poses ( n = 21), or two constrictive, low power poses ( n = 20) for 1-min each. The results showed that yoga poses in comparison to 'power poses' increased self-esteem. This effect was mediated by an increased subjective sense of energy and was observed when baseline trait self-esteem was controlled for. These results suggest that the effects of performing open, expansive body postures may be driven by processes other than the poses' association with interpersonal power and dominance. This study demonstrates that positive effects of yoga practice can occur after performing yoga poses for only 2 min.

Scenario-targeted toxicity assessment through multiple endpoint bioassays in a soil posing unacceptable environmental risk according to regulatory screening values.

Science.gov (United States)

Rodriguez-Ruiz, A; Etxebarria, J; Boatti, L; Marigómez, I

2015-09-01

Lanestosa is a chronically polluted site (derelict mine) where the soil (Lanestosa (LA) soil) exceeds screening values (SVs) of regulatory policies in force (Basque Country; Europe) for Zn, Pb and Cd. A scenario-targeted toxicity assessment was carried out on the basis of a multi-endpoint bioassay approach. Acute and chronic toxicity bioassays were conducted with selected test species (Vibrio fischeri, Dictyostelium discoideum, Lactuca sativa, Raphanus sativus and Eisenia fetida) in combination with chemical analysis of soils and elutriates and with bioaccumulation studies in earthworms. Besides, the toxicity profile was compared with that of the mine runoff (RO) soil and of a fresh artificially polluted soil (LAAPS) resembling LA soil pollutant profile. Extractability studies in LA soil revealed that Pb, Zn and Cd were highly available for exchange and/or release into the environment. Indeed, Pb and Zn were accumulated in earthworms and LA soil resulted to be toxic. Soil respiration, V. fischeri, vegetative and developmental cycles of D. discoideum and survival and juvenile production of E. fetida were severely affected. These results confirmed that LA soil had unacceptable environmental risk and demanded intervention. In contrast, although Pb and Zn concentrations in RO soil revealed also unacceptable risk, both metal extractability and toxicity were much lower than in LA soil. Thus, within the polluted site, the need for intervention varied between areas that posed dissimilar risk. Besides, since LAAPS, with a high exchangeable metal fraction, was the most toxic, ageing under in situ natural conditions seemingly contributed to attenuate LA soil risk. As a whole, combining multi-endpoint bioassays with scenario-targeted analysis (including leaching and ageing) provides reliable risk assessment in soils posing unacceptable environmental risk according to SVs, which is useful to optimise the required intervention measures.

An alternative approach to risk rank chemicals on the threat they pose to the aquatic environment.

Science.gov (United States)

Johnson, Andrew C; Donnachie, Rachel L; Sumpter, John P; Jürgens, Monika D; Moeckel, Claudia; Pereira, M Gloria

2017-12-01

This work presents a new and unbiased method of risk ranking chemicals based on the threat they pose to the aquatic environment. The study ranked 12 metals, 23 pesticides, 11 other persistent organic pollutants (POPs), 13 pharmaceuticals, 10 surfactants and similar compounds and 2 nanoparticles (total of 71) of concern against one another by comparing their median UK river water and median ecotoxicity effect concentrations. To complement this, by giving an assessment on potential wildlife impacts, risk ranking was also carried out by comparing the lowest 10th percentile of the effects data with the highest 90th percentile of the exposure data. In other words, risk was pared down to just toxicity versus exposure. Further modifications included incorporating bioconcentration factors, using only recent water measurements and excluding either lethal or sub-lethal effects. The top ten chemicals, based on the medians, which emerged as having the highest risk to organisms in UK surface waters using all the ecotoxicity data were copper, aluminium, zinc, ethinylestradiol (EE2), linear alkylbenzene sulfonate (LAS), triclosan, manganese, iron, methomyl and chlorpyrifos. By way of contrast, using current UK environmental quality standards as the comparator to median UK river water concentrations would have selected 6 different chemicals in the top ten. This approach revealed big differences in relative risk; for example, zinc presented a million times greater risk then metoprolol and LAS 550 times greater risk than nanosilver. With the exception of EE2, most pharmaceuticals were ranked as having a relatively low risk. Copyright © 2017 Elsevier B.V. All rights reserved.

Potential Health Risks Posed by Plant-Derived Cumulative Neurotoxic Bufadienolides in South Africa

Directory of Open Access Journals (Sweden)

Christo Botha

2016-03-01

Full Text Available Bufadienolide-type cardiac glycosides have a worldwide distribution and are mainly synthesized by plants, but there are also animal sources. In South Africa, members of three genera of the Crassulaceae (Cotyledon, Tylecodon and Kalanchoe cause a unique chronic form of cardiac glycoside poisoning, predominantly in small stock. This paretic/paralytic condition is referred to as “krimpsiekte”, cotyledonosis or “nenta”. “Krimpsiekte” is a plant poisoning only reported from South Africa and is regarded as the most important plant poisoning of small stock in the semi-arid Little Karoo and southern fringes of the Great Karoo. The toxicosis is caused by cumulative bufadienolides which have neurotoxic properties. Four types of cumulative neurotoxic bufadienolides, namely cotyledoside, and the tyledosides, orbicusides and lanceotoxins, have been isolated. Based on the structure activity relationships and certain toxicokinetic parameters possible reasons for their accumulation are presented. Consumption of edible tissues from animals that have ingested these plants poses a potential risk to humans.

On piecewise constant level-set (PCLS) methods for the identification of discontinuous parameters in ill-posed problems

International Nuclear Information System (INIS)

De Cezaro, A; Leitão, A; Tai, X-C

2013-01-01

We investigate level-set-type methods for solving ill-posed problems with discontinuous (piecewise constant) coefficients. The goal is to identify the level sets as well as the level values of an unknown parameter function on a model described by a nonlinear ill-posed operator equation. The PCLS approach is used here to parametrize the solution of a given operator equation in terms of a L 2 level-set function, i.e. the level-set function itself is assumed to be a piecewise constant function. Two distinct methods are proposed for computing stable solutions of the resulting ill-posed problem: the first is based on Tikhonov regularization, while the second is based on the augmented Lagrangian approach with total variation penalization. Classical regularization results (Engl H W et al 1996 Mathematics and its Applications (Dordrecht: Kluwer)) are derived for the Tikhonov method. On the other hand, for the augmented Lagrangian method, we succeed in proving the existence of (generalized) Lagrangian multipliers in the sense of (Rockafellar R T and Wets R J-B 1998 Grundlehren der Mathematischen Wissenschaften (Berlin: Springer)). Numerical experiments are performed for a 2D inverse potential problem (Hettlich F and Rundell W 1996 Inverse Problems 12 251–66), demonstrating the capabilities of both methods for solving this ill-posed problem in a stable way (complicated inclusions are recovered without any a priori geometrical information on the unknown parameter). (paper)

Boneless Pose Editing and Animation

DEFF Research Database (Denmark)

Bærentzen, Jakob Andreas; Hansen, Kristian Evers; Erleben, Kenny

2007-01-01

In this paper, we propose a pose editing and animation method for triangulated surfaces based on a user controlled partitioning of the model into deformable parts and rigid parts which are denoted handles. In our pose editing system, the user can sculpt a set of poses simply by transforming...... the handles for each pose. Using Laplacian editing, the deformable parts are deformed to match the handles. In our animation system the user can constrain one or several handles in order to define a new pose. New poses are interpolated from the examples poses, by solving a small non-linear optimization...... problem in order to obtain the interpolation weights. While the system can be used simply for building poses, it is also an animation system. The user can specify a path for a given constraint and the model is animated correspondingly....

Does intake of trace elements through urban gardening in Copenhagen pose a risk to human health?

International Nuclear Information System (INIS)

Warming, Marlies; Hansen, Mette G.; Holm, Peter E.; Magid, Jakob; Hansen, Thomas H.; Trapp, Stefan

2015-01-01

This study investigates the potential health risk from urban gardening. The concentrations of the trace elements arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), nickel (Ni), and zinc (Zn) in five common garden crops from three garden sites in Copenhagen were measured. Concentrations (mg/kg dw) of As were 0.002–0.21, Cd 0.03–0.25, Cr < 0.09–0.38, Cu 1.8–8.7, Ni < 0.23–0.62, Pb 0.05–1.56, and Zn 10–86. Generally, elemental concentrations in the crops do not reflect soil concentrations, nor exceed legal standards for Cd and Pb in food. Hazard quotients (HQs) were calculated from soil ingestion, vegetable consumption, measured trace element concentrations and tolerable intake levels. The HQs for As, Cd, Cr, Cu, Ni, and Zn do not indicate a health risk through urban gardening in Copenhagen. Exposure to Pb contaminated sites may lead to unacceptable risk not caused by vegetable consumption but by unintentional soil ingestion. - Highlights: • We measured trace metal concentrations in urban soil and vegetables. • We calculated hazard quotients (HQs) to determine the human health risk. • Consumption of urban vegetables does not result in HQs exceeding unity. • Unintentional ingestion of contaminated soil causes a risk to the human health. - Consumption of vegetables grown in Copenhagen does not pose a risk to the human health, while unintentional ingestion of contaminated soil remains a risk factor with respect to lead

Atmospheric turbulence profiling with unknown power spectral density

Science.gov (United States)

Helin, Tapio; Kindermann, Stefan; Lehtonen, Jonatan; Ramlau, Ronny

2018-04-01

Adaptive optics (AO) is a technology in modern ground-based optical telescopes to compensate for the wavefront distortions caused by atmospheric turbulence. One method that allows to retrieve information about the atmosphere from telescope data is so-called SLODAR, where the atmospheric turbulence profile is estimated based on correlation data of Shack-Hartmann wavefront measurements. This approach relies on a layered Kolmogorov turbulence model. In this article, we propose a novel extension of the SLODAR concept by including a general non-Kolmogorov turbulence layer close to the ground with an unknown power spectral density. We prove that the joint estimation problem of the turbulence profile above ground simultaneously with the unknown power spectral density at the ground is ill-posed and propose three numerical reconstruction methods. We demonstrate by numerical simulations that our methods lead to substantial improvements in the turbulence profile reconstruction compared to the standard SLODAR-type approach. Also, our methods can accurately locate local perturbations in non-Kolmogorov power spectral densities.

A review of cooperative and uncooperative spacecraft pose determination techniques for close-proximity operations

Science.gov (United States)

Opromolla, Roberto; Fasano, Giancarmine; Rufino, Giancarlo; Grassi, Michele

2017-08-01

The capability of an active spacecraft to accurately estimate its relative position and attitude (pose) with respect to an active/inactive, artificial/natural space object (target) orbiting in close-proximity is required to carry out various activities like formation flying, on-orbit servicing, active debris removal, and space exploration. According to the specific mission scenario, the pose determination task involves both theoretical and technological challenges related to the search for the most suitable algorithmic solution and sensor architecture, respectively. As regards the latter aspect, electro-optical sensors represent the best option as their use is compatible with mass and power limitation of micro and small satellites, and their measurements can be processed to estimate all the pose parameters. Overall, the degree of complexity of the challenges related to pose determination largely varies depending on the nature of the targets, which may be actively/passively cooperative, uncooperative but known, or uncooperative and unknown space objects. In this respect, while cooperative pose determination has been successfully demonstrated in orbit, the uncooperative case is still under study by universities, research centers, space agencies and private companies. However, in both the cases, the demand for space applications involving relative navigation maneuvers, also in close-proximity, for which pose determination capabilities are mandatory, is significantly increasing. In this framework, a review of state-of-the-art techniques and algorithms developed in the last decades for cooperative and uncooperative pose determination by processing data provided by electro-optical sensors is herein presented. Specifically, their main advantages and drawbacks in terms of achieved performance, computational complexity, and sensitivity to variability of pose and target geometry, are highlighted.

Lead and Cadmium: Priorities for action from UNEP’s perspective for addressing risks posed by these two heavy metals

Directory of Open Access Journals (Sweden)

Piper D.

2013-04-01

Full Text Available The United Nations Environment Programme (UNEP has been focusing on actions with regard to lead and cadmium since 2001 when the work of the Partnership for Clean Fuels and Vehicles (PCFV was initiated. The development and finalization of the reviews of scientific information on lead and cadmium facilitated discussions among Governments in relation to the need for global action with regard to these heavy metals. UNEP continues to address priority areas for focusing to reduce risks posed by lead and cadmium. The Global Alliance to Eliminate Lead Paint (GAELP is a clear example for addressing those risks; however more work is expected to be done in relation to these key issues.

How Much Is that Exam Grade Really Worth? An Estimation of Student Risk Aversion to Their Unknown Final College Course Grades

Science.gov (United States)

Nalley, Lanier; McKenzie, Andrew

2011-01-01

This study created an experimental design with which students can empirically assess their risk behavior with respect to exam grades within an expected utility framework. Specifically, the authors analyzed students' risk preferences associated with taking exams and earning a "risky" unknown grade versus not taking exams and instead…

Camera pose estimation for augmented reality in a small indoor dynamic scene

Science.gov (United States)

Frikha, Rawia; Ejbali, Ridha; Zaied, Mourad

2017-09-01

Camera pose estimation remains a challenging task for augmented reality (AR) applications. Simultaneous localization and mapping (SLAM)-based methods are able to estimate the six degrees of freedom camera motion while constructing a map of an unknown environment. However, these methods do not provide any reference for where to insert virtual objects since they do not have any information about scene structure and may fail in cases of occlusion of three-dimensional (3-D) map points or dynamic objects. This paper presents a real-time monocular piece wise planar SLAM method using the planar scene assumption. Using planar structures in the mapping process allows rendering virtual objects in a meaningful way on the one hand and improving the precision of the camera pose and the quality of 3-D reconstruction of the environment by adding constraints on 3-D points and poses in the optimization process on the other hand. We proposed to benefit from the 3-D planes rigidity motion in the tracking process to enhance the system robustness in the case of dynamic scenes. Experimental results show that using a constrained planar scene improves our system accuracy and robustness compared with the classical SLAM systems.

The art of problem posing

CERN Document Server

Brown, Stephen I

1990-01-01

Updated and expanded, this second edition satisfies the same philosophical objective as the first -- to show the importance of problem posing. Although interest in mathematical problem solving increased during the past decade, problem posing remained relatively ignored. The Art of Problem Posing draws attention to this equally important act and is the innovator in the field. Special features include: * an exploration ofthe logical relationship between problem posing and problem solving * a special chapter devoted to teaching problem posing as a separate course * sketches, drawings, diagrams, and cartoons that illustrate the schemes proposed * a special section on writing in mathematics.

A preliminary approach to quantifying the overall environmental risks posed by development projects during environmental impact assessment.

Science.gov (United States)

Nicol, Sam; Chadès, Iadine

2017-01-01

Environmental impact assessment (EIA) is used globally to manage the impacts of development projects on the environment, so there is an imperative to demonstrate that it can effectively identify risky projects. However, despite the widespread use of quantitative predictive risk models in areas such as toxicology, ecosystem modelling and water quality, the use of predictive risk tools to assess the overall expected environmental impacts of major construction and development proposals is comparatively rare. A risk-based approach has many potential advantages, including improved prediction and attribution of cause and effect; sensitivity analysis; continual learning; and optimal resource allocation. In this paper we investigate the feasibility of using a Bayesian belief network (BBN) to quantify the likelihood and consequence of non-compliance of new projects based on the occurrence probabilities of a set of expert-defined features. The BBN incorporates expert knowledge and continually improves its predictions based on new data as it is collected. We use simulation to explore the trade-off between the number of data points and the prediction accuracy of the BBN, and find that the BBN could predict risk with 90% accuracy using approximately 1000 data points. Although a further pilot test with real project data is required, our results suggest that a BBN is a promising method to monitor overall risks posed by development within an existing EIA process given a modest investment in data collection.

X-ray examinations pose little risk

International Nuclear Information System (INIS)

Servomaa, A.; Komppa, T.

1997-01-01

X-ray examinations account for about 15 per cent of Finns' radiation exposure and for roughly one out of a hundred deaths from cancer. The risk is small when compared to other risks in life and to the health benefits obtained from the examinations. About 4.1 million x-ray examinations were conducted in Finland in 1995, i.e. an average of 0.8 examinations per inhabitant. The mean effective dose was about 0.67 mSv per examination and about 0.54 mSv per inhabitant. Natural background radiation causes an annual radiation dose of approximately 3 mSv per person. Examinations of bones and soft tissues accounted for the highest number of x-ray images, roughly 2.1 million, of which half were examinations of the extremities. Some 1.3 million x-ray images were taken of the pulmonary organs, most of them being examinations of the lungs. Computed tomography and examinations of the gastrointestinal tract accounted for about 130,000 images each. To assess the radiation risk involved in x-ray examinations, we need knowledge or an estimate of the radiation doses of organs sensitive to radiation. Efficient calculation methods are available for this purpose. (orig.)

Pose Space Surface Manipulation

Directory of Open Access Journals (Sweden)

Yusuke Yoshiyasu

2012-01-01

Full Text Available Example-based mesh deformation techniques produce natural and realistic shapes by learning the space of deformations from examples. However, skeleton-based methods cannot manipulate a global mesh structure naturally, whereas the mesh-based approaches based on a translational control do not allow the user to edit a local mesh structure intuitively. This paper presents an example-driven mesh editing framework that achieves both global and local pose manipulations. The proposed system is built with a surface deformation method based on a two-step linear optimization technique and achieves direct manipulations of a model surface using translational and rotational controls. With the translational control, the user can create a model in natural poses easily. The rotational control can adjust the local pose intuitively by bending and twisting. We encode example deformations with a rotation-invariant mesh representation which handles large rotations in examples. To incorporate example deformations, we infer a pose from the handle translations/rotations and perform pose space interpolation, thereby avoiding involved nonlinear optimization. With the two-step linear approach combined with the proposed multiresolution deformation method, we can edit models at interactive rates without losing important deformation effects such as muscle bulging.

A preliminary approach to quantifying the overall environmental risks posed by development projects during environmental impact assessment.

Directory of Open Access Journals (Sweden)

Sam Nicol

Full Text Available Environmental impact assessment (EIA is used globally to manage the impacts of development projects on the environment, so there is an imperative to demonstrate that it can effectively identify risky projects. However, despite the widespread use of quantitative predictive risk models in areas such as toxicology, ecosystem modelling and water quality, the use of predictive risk tools to assess the overall expected environmental impacts of major construction and development proposals is comparatively rare. A risk-based approach has many potential advantages, including improved prediction and attribution of cause and effect; sensitivity analysis; continual learning; and optimal resource allocation. In this paper we investigate the feasibility of using a Bayesian belief network (BBN to quantify the likelihood and consequence of non-compliance of new projects based on the occurrence probabilities of a set of expert-defined features. The BBN incorporates expert knowledge and continually improves its predictions based on new data as it is collected. We use simulation to explore the trade-off between the number of data points and the prediction accuracy of the BBN, and find that the BBN could predict risk with 90% accuracy using approximately 1000 data points. Although a further pilot test with real project data is required, our results suggest that a BBN is a promising method to monitor overall risks posed by development within an existing EIA process given a modest investment in data collection.

Infant Sleep Positioners Pose Suffocation Risk

Science.gov (United States)

... For Consumers Consumer Updates Do Not Use Infant Sleep Positioners Due to the Risk of Suffocation Share ... to top Safety Advice for Putting Babies to Sleep NEVER use infant sleep positioners. Using this type ...

Statistical Model-Based Face Pose Estimation

Institute of Scientific and Technical Information of China (English)

GE Xinliang; YANG Jie; LI Feng; WANG Huahua

2007-01-01

A robust face pose estimation approach is proposed by using face shape statistical model approach and pose parameters are represented by trigonometric functions. The face shape statistical model is firstly built by analyzing the face shapes from different people under varying poses. The shape alignment is vital in the process of building the statistical model. Then, six trigonometric functions are employed to represent the face pose parameters. Lastly, the mapping function is constructed between face image and face pose by linearly relating different parameters. The proposed approach is able to estimate different face poses using a few face training samples. Experimental results are provided to demonstrate its efficiency and accuracy.

Evaluating health risks posed by heavy metals to humans consuming blood cockles (Anadara granosa) from the Upper Gulf of Thailand.

Science.gov (United States)

Sudsandee, Suntorn; Tantrakarnapa, Kraichat; Tharnpoophasiam, Prapin; Limpanont, Yanin; Mingkhwan, Ratchaneekorn; Worakhunpiset, Suwalee

2017-06-01

There is global concern about heavy metal contamination in the environment. Adverse health effects can be caused by heavy metals in contaminated food and water. Therefore, environmental monitoring studies and risk assessments should be conducted periodically. In this study, we measured levels of Cd, Cr, Cu, Hg, Mn, Ni, Pb, and Zn in blood cockles (Anadara granosa) collected from three locations in the Upper Gulf of Thailand. Hazard quotients and hazard indices were calculated to evaluate the health risks posed by heavy metals in consumed blood cockles. Heavy metal concentrations in all of the blood cockle samples were lower than the relevant food standards. The hazard quotients and hazard indices were heavy metals in blood cockles over a human lifetime.

Business unknowns shape oil industry risks

International Nuclear Information System (INIS)

Pane, R.

1991-01-01

Strategic thinking about an exploration and production program requires a careful assessment of risk, which can be defined as variability in the components of value creation. This article surveys, categorizes, and ranks business risks in the upstream petroleum business. It can serve as a checklist for thinking strategically about an E and P program

Health risks posed to infants in rural China by exposure to short- and medium-chain chlorinated paraffins in breast milk.

Science.gov (United States)

Xia, Dan; Gao, Li-Rong; Zheng, Ming-Hui; Li, Jing-Guang; Zhang, Lei; Wu, Yong-Ning; Qiao, Lin; Tian, Qi-Chang; Huang, Hui-Ting; Liu, Wen-Bin; Su, Gui-Jin; Liu, Guo-Rui

2017-06-01

Chlorinated paraffins (CPs) are complex mixtures of synthetic chemicals found widely in environmental matrices. Short-chain CPs (SCCPs) are candidate persistent organic pollutants under the Stockholm Convention. There should be great concern about human exposure to SCCPs. Data on CP concentrations in human breast milk is scarce. This is the first study in which background SCCP and medium-chain CP (MCCP) body burdens in the general rural population of China have been estimated and health risks posed to nursing infants by CPs in breast milk assessed. The concentrations of 48 SCCP and MCCP formula congeners were determined in 24 pooled human milk samples produced from 1412 individual samples from eight provinces in 2007 and 16 provinces in 2011. The samples were analyzed by comprehensive two-dimensional gas chromatography electron capture negative ionization high-resolution time-of-flight mass spectrometry. The median SCCP and MCCP concentrations were 303 and 35.7ngg -1 lipid weight, respectively, for the 2007 samples and 360 and 45.4ngg -1 lipid weight, respectively, for the 2011 samples. The C 10 and C 14 homologs were the dominant CP carbon-chain-length groups, contributing 51% and 82% of the total SCCP and MCCP concentrations, respectively. There are probably multiple CP sources to the general Chinese population and numerous exposure pathways. The median estimated daily SCCP and MCCP intakes for nursing infants were 1310 and 152ngkg -1 d -1 , respectively, in 2007 and 1520 and 212ngkg -1 d -1 , respectively, in 2011. SCCPs do not currently pose significant risks to infants in China. However, it is necessary to continuously monitor CP concentrations and health risks because CP concentrations in Chinese human breast milk are increasing. Copyright © 2017 Elsevier Ltd. All rights reserved.

Pengenalan Pose Tangan Menggunakan HuMoment

Directory of Open Access Journals (Sweden)

Dina Budhi Utami

2017-02-01

Full Text Available Computer vision yang didasarkan pada pengenalan bentuk memiliki banyak potensi dalam interaksi manusia dan komputer. Pose tangan dapat dijadikan simbol interaksi manusia dengan komputer seperti halnya pada penggunaan berbagai pose tangan pada bahasa isyarat. Berbagai pose tangan dapat digunakan untuk menggantikan fungsi mouse, untuk mengendalikan robot, dan sebagainya. Penelitian ini difokuskan pada pembangunan sistem pengenalan pose tangan menggunakan HuMoment. Proses pengenalan pose tangan dimulai dengan melakukan segmentasi citra masukan untuk menghasilkan citra ROI (Region of Interest yaitu area telapak tangan. Selanjutnya dilakukan proses deteksi tepi. Kemudian dilakukan ekstraksi nilai HuMoment. Nilai HuMoment dikuantisasikan ke dalam bukukode yang dihasilkan dari proses pelatihan menggunakan K-Means. Proses kuantisasi dilakukan dengan menghitung nilai Euclidean Distance terkecil antara nilai HuMomment citra masukan dan bukukode. Berdasarkan hasil penelitian, nilai akurasi sistem dalam mengenali pose tangan adalah 88.57%.

Foreign-funded M&A Poses No Threatto China’s Economic Security

Institute of Scientific and Technical Information of China (English)

王志乐

2007-01-01

Foreign funded M■A(Mergers ■ Acquisitions) activity is becoming increasingly common in China.In this article Wang Zhile assesses the effects and risks associated with M■A,finding that foreign funded M■A activity is immensely beneficial to China and poses no threat to economic security.

Regulating the unknown: Managing the occupational health risks of nanomedical technologies and nanopharmaceuticals in the research laboratory

Science.gov (United States)

Ersin, Ozlem Hacer

Novel technologies and their resultant products demand fresh ways of thinking about pre-market risk analysis and post-market surveillance. A regulatory framework that is responsive to emerging knowledge about the hazards of novel technologies offers repeatable and transparent processes and remains economically and socially feasible. Workers are an especially vulnerable population who are exposed to unknown hazards of novel technologies and serve often as unwitting sentinels of impending risks. This Grounded Theory-based case study identifies gaps in our current ability to regulate novel technologies so as to minimize occupational health risks and offers necessary modifications for an environment that is conducive to proper regulation. Nanopharmaceuticals and the nano-based technologies at their base are used by way of exemplar technologies that are currently taxing the ability of the regulatory system to provide adequate oversight. Ambiguities of definition, absence of a tracking system (of who is doing nanotechnology research), and the paucity of scientific evidence to support risk management efforts are among the findings of the study and need to be addressed as ameliorative steps toward an effective regulatory structure.

Handheld pose tracking using vision-inertial sensors with occlusion handling

Science.gov (United States)

Li, Juan; Slembrouck, Maarten; Deboeverie, Francis; Bernardos, Ana M.; Besada, Juan A.; Veelaert, Peter; Aghajan, Hamid; Casar, José R.; Philips, Wilfried

2016-07-01

Tracking of a handheld device's three-dimensional (3-D) position and orientation is fundamental to various application domains, including augmented reality (AR), virtual reality, and interaction in smart spaces. Existing systems still offer limited performance in terms of accuracy, robustness, computational cost, and ease of deployment. We present a low-cost, accurate, and robust system for handheld pose tracking using fused vision and inertial data. The integration of measurements from embedded accelerometers reduces the number of unknown parameters in the six-degree-of-freedom pose calculation. The proposed system requires two light-emitting diode (LED) markers to be attached to the device, which are tracked by external cameras through a robust algorithm against illumination changes. Three data fusion methods have been proposed, including the triangulation-based stereo-vision system, constraint-based stereo-vision system with occlusion handling, and triangulation-based multivision system. Real-time demonstrations of the proposed system applied to AR and 3-D gaming are also included. The accuracy assessment of the proposed system is carried out by comparing with the data generated by the state-of-the-art commercial motion tracking system OptiTrack. Experimental results show that the proposed system has achieved high accuracy of few centimeters in position estimation and few degrees in orientation estimation.

Contemporary management of lymph node metastases from an unknown primary to the neck : II. A review of therapeutic options

NARCIS (Netherlands)

Strojan, Primoz; Ferlito, Alfio; Langendijk, Johannes A.; Corry, June; Woolgar, Julia A.; Rinaldo, Alessandra; Silver, Carl E.; Paleri, Vinidh; Fagan, Johannes J.; Pellitteri, Phillip K.; Haigentz, Missak; Suarez, Carlos; Robbins, K. Thomas; Rodrigo, Juan P.; Olsen, Kerry D.; Hinni, Michael L.; Werner, Jochen A.; Mondin, Vanni; Kowalski, Luiz P.; Devaney, Kenneth O.; de Bree, Remco; Takes, Robert P.; Wolf, Gregory T.; Shaha, Ashok R.; Genden, Eric M.; Barnes, Leon

Although uncommon, cancer of an unknown primary (CUP) metastatic to cervical lymph nodes poses a range of dilemmas relating to optimal treatment. The ideal resolution would be a properly designed prospective randomized trial, but it is unlikely that this will ever be conducted in this group of

Contemporary management of lymph node metastases from an unknown primary to the neck: II. a review of therapeutic options

NARCIS (Netherlands)

Strojan, P.; Ferlito, A.; Langendijk, J.A.; Corry, J.; Woolgar, J.A.; Rinaldo, A.; Silver, C.E.; Paleri, V.; Fagan, J.J.; Pellitteri, P.K.; Haigentz Jr., M.; Suarez, C.; Robbins, K.T.; Rodrigo, J.P.; Olsen, K.D.; Hinni, M.L.; Werner, J.A.; Mondin, V.; Kowalski, L.P.; Devaney, K.O.; Bree, R. de; Takes, R.P.; Wolf, G.T.; Shaha, A.R.; Genden, E.M.; Barnes, L.

2013-01-01

Although uncommon, cancer of an unknown primary (CUP) metastatic to cervical lymph nodes poses a range of dilemmas relating to optimal treatment. The ideal resolution would be a properly designed prospective randomized trial, but it is unlikely that this will ever be conducted in this group of

Problem posing reflections and applications

CERN Document Server

Brown, Stephen I

2014-01-01

As a result of the editors' collaborative teaching at Harvard in the late 1960s, they produced a ground-breaking work -- The Art Of Problem Posing -- which related problem posing strategies to the already popular activity of problem solving. It took the concept of problem posing and created strategies for engaging in that activity as a central theme in mathematics education. Based in part upon that work and also upon a number of articles by its authors, other members of the mathematics education community began to apply and expand upon their ideas. This collection of thirty readings is a tes

Children with hypercholesterolemia of unknown cause: Value of genetic risk scores.

Science.gov (United States)

Sjouke, Barbara; Tanck, Michael W T; Fouchier, Sigrid W; Defesche, Joep C; Hutten, Barbara A; Wiegman, Albert; Kastelein, John J P; Hovingh, G Kees

2016-01-01

Familial hypercholesterolemia (FH) is caused by mutations in LDLR, APOB, or PCSK9, and in a previous study, we identified a causative mutation in these FH genes in 95% (255 of 269) of children with the FH phenotype. It has been hypothesized that a polygenic form of hypercholesterolemia is present in FH patients in whom no mutation is identified in the 3 FH genes. To address whether a polygenic form of hypercholesterolemia, defined as high-weighted effect of low-density lipoprotein cholesterol (LDL-C) raising SNPs expressed as the genetic risk score (GRS), is present in the remaining 14 children. On reassessment of the molecular diagnosis and clinical phenotype, 8 FH kindreds met the criteria for hypercholesterolemia of unknown cause and were included in this study. We calculated a weighted GRS comprising 10 established LDL-C-associated SNPs and the APOE genotype in these index cases and evaluated whether the index cases were characterized by an increased GRS compared to 26 first-degree relatives. Phenotypically affected and unaffected individuals could not be distinguished based on any of the risk scores. In this and our previous study, we show that a causal mutation in LDLR, APOB, and PCSK9 can be identified in almost all children with a definite clinical diagnosis of FH. In the small group of patients without a mutation, we did not observe a higher GRS compared with unaffected relatives, which suggests that the FH phenotype is not caused by the aggregate of LDL-C increasing SNPs. Our data imply that application of the GRS is not instrumental as a diagnostic tool to individually define clinically diagnosed FH patients with polygenic hypercholesterolemia in our study population. Copyright © 2016 National Lipid Association. Published by Elsevier Inc. All rights reserved.

Mitigation of the threat posed to transfusion by donors traveling to Zika-affected areas: a Canadian risk-based approach.

Science.gov (United States)

Germain, Marc; Delage, Gilles; O'Brien, Sheila F; Grégoire, Yves; Fearon, Margaret; Devine, Dana

2017-10-01

The recent spread of the Zika virus to the Americas and the recognition that it can cause severe disease in the developing fetus has prompted the adoption of measures to mitigate the risk that this virus might pose to transfusion safety. In nonendemic countries, the risk to transfusion results from donors traveling to an endemic region. Canada implemented a 21-day temporary deferral for prospective donors who traveled to such regions. We present the rationale for this policy, including a quantitative risk assessment supported by a Monte Carlo simulation. The model considered the following parameters, each with specified values and ranges: the probability that a donor recently returned from a Zika-endemic region, the duration of travel to this region, the daily risk of acquiring Zika while in an endemic region, and the incubation and viremic periods. We ran the simulation 20 times, each with 10 million iterations. In the absence of any travel deferral, 32 donors (range, 20-46 donors) would be able to donate while still being at risk of transmitting Zika, corresponding to a rate of 1:312,500 (range, 1:217,000 to 1:500,000). None of these donors would be viremic beyond 21 days after returning from their travel, with a risk estimated at less than 1:200,000,000. A 21-day temporary travel deferral offers an extremely wide margin of safety for the possible transmission of Zika by a donation obtained from someone who recently returned from a country where the virus is circulating. © 2017 AABB.

Human action recognition based on estimated weak poses

Science.gov (United States)

Gong, Wenjuan; Gonzàlez, Jordi; Roca, Francesc Xavier

2012-12-01

We present a novel method for human action recognition (HAR) based on estimated poses from image sequences. We use 3D human pose data as additional information and propose a compact human pose representation, called a weak pose, in a low-dimensional space while still keeping the most discriminative information for a given pose. With predicted poses from image features, we map the problem from image feature space to pose space, where a Bag of Poses (BOP) model is learned for the final goal of HAR. The BOP model is a modified version of the classical bag of words pipeline by building the vocabulary based on the most representative weak poses for a given action. Compared with the standard k-means clustering, our vocabulary selection criteria is proven to be more efficient and robust against the inherent challenges of action recognition. Moreover, since for action recognition the ordering of the poses is discriminative, the BOP model incorporates temporal information: in essence, groups of consecutive poses are considered together when computing the vocabulary and assignment. We tested our method on two well-known datasets: HumanEva and IXMAS, to demonstrate that weak poses aid to improve action recognition accuracies. The proposed method is scene-independent and is comparable with the state-of-art method.

Adaptive nonlinear robust relative pose control of spacecraft autonomous rendezvous and proximity operations.

Science.gov (United States)

Sun, Liang; Huo, Wei; Jiao, Zongxia

2017-03-01

This paper studies relative pose control for a rigid spacecraft with parametric uncertainties approaching to an unknown tumbling target in disturbed space environment. State feedback controllers for relative translation and relative rotation are designed in an adaptive nonlinear robust control framework. The element-wise and norm-wise adaptive laws are utilized to compensate the parametric uncertainties of chaser and target spacecraft, respectively. External disturbances acting on two spacecraft are treated as a lumped and bounded perturbation input for system. To achieve the prescribed disturbance attenuation performance index, feedback gains of controllers are designed by solving linear matrix inequality problems so that lumped disturbance attenuation with respect to the controlled output is ensured in the L 2 -gain sense. Moreover, in the absence of lumped disturbance input, asymptotical convergence of relative pose are proved by using the Lyapunov method. Numerical simulations are performed to show that position tracking and attitude synchronization are accomplished in spite of the presence of couplings and uncertainties. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

Concentrations of and health risks posed by polychlorinated dibenzo-p-dioxins and dibenzofurans around industrial sites in Hebei Province, China

DEFF Research Database (Denmark)

Han, Ying; Liu, Wenbin; Hansen, Hans Chr. Bruun

2016-01-01

Sintering and steel production as the main emission sources of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) may affect environment and human health. The concentrations, profiles, and distributions of PCDD/Fs in soil samples from around four typical sintering and steel production...... plants in Hebei Province, China, were determined. Forty-six soil samples were collected at distances from 500 to 9000 m from industrial plant chimneys. The concentrations of total 17 2,3,7,8-substituted PCDD/F congeners in the soil samples from sites A, B, C, and D were in the range 11-130, 13-284, 2...... will be exposed to low amounts of PCDD/Fs in soil from around the industrial sites, and this exposure will pose potential health risks for the local population living at distances of less than 1000 m from nearest stack but will have no high health risks for people living further away. These results...

Multi-task pose-invariant face recognition.

Science.gov (United States)

Ding, Changxing; Xu, Chang; Tao, Dacheng

2015-03-01

Face images captured in unconstrained environments usually contain significant pose variation, which dramatically degrades the performance of algorithms designed to recognize frontal faces. This paper proposes a novel face identification framework capable of handling the full range of pose variations within ±90° of yaw. The proposed framework first transforms the original pose-invariant face recognition problem into a partial frontal face recognition problem. A robust patch-based face representation scheme is then developed to represent the synthesized partial frontal faces. For each patch, a transformation dictionary is learnt under the proposed multi-task learning scheme. The transformation dictionary transforms the features of different poses into a discriminative subspace. Finally, face matching is performed at patch level rather than at the holistic level. Extensive and systematic experimentation on FERET, CMU-PIE, and Multi-PIE databases shows that the proposed method consistently outperforms single-task-based baselines as well as state-of-the-art methods for the pose problem. We further extend the proposed algorithm for the unconstrained face verification problem and achieve top-level performance on the challenging LFW data set.

Exemplar-based human action pose correction.

Science.gov (United States)

Shen, Wei; Deng, Ke; Bai, Xiang; Leyvand, Tommer; Guo, Baining; Tu, Zhuowen

2014-07-01

The launch of Xbox Kinect has built a very successful computer vision product and made a big impact on the gaming industry. This sheds lights onto a wide variety of potential applications related to action recognition. The accurate estimation of human poses from the depth image is universally a critical step. However, existing pose estimation systems exhibit failures when facing severe occlusion. In this paper, we propose an exemplar-based method to learn to correct the initially estimated poses. We learn an inhomogeneous systematic bias by leveraging the exemplar information within a specific human action domain. Furthermore, as an extension, we learn a conditional model by incorporation of pose tags to further increase the accuracy of pose correction. In the experiments, significant improvements on both joint-based skeleton correction and tag prediction are observed over the contemporary approaches, including what is delivered by the current Kinect system. Our experiments for the facial landmark correction also illustrate that our algorithm can improve the accuracy of other detection/estimation systems.

Students’ Creativity: Problem Posing in Structured Situation

Science.gov (United States)

Amalina, I. K.; Amirudin, M.; Budiarto, M. T.

2018-01-01

This is a qualitative research concerning on students’ creativity on problem posing task. The study aimed at describing the students’ creative thinking ability to pose the mathematics problem in structured situations with varied condition of given problems. In order to find out the students’ creative thinking ability, an analysis of mathematics problem posing test based on fluency, novelty, and flexibility and interview was applied for categorizing students’ responses on that task. The data analysis used the quality of problem posing and categorized in 4 level of creativity. The results revealed from 29 secondary students grade 8, a student in CTL (Creative Thinking Level) 1 met the fluency. A student in CTL 2 met the novelty, while a student in CTL 3 met both fluency and novelty and no one in CTL 4. These results are affected by students’ mathematical experience. The findings of this study highlight that student’s problem posing creativity are dependent on their experience in mathematics learning and from the point of view of which students start to pose problem.

Do shade-grown coffee plantations pose a disease risk for wild birds?

Science.gov (United States)

Hernandez, Sonia M; Peters, Valerie E; Weygandt, P Logan; Jimenez, Carlos; Villegas, Pedro; O'Connor, Barry; Yabsley, Michael J; Garcia, Maricarmen; Riblet, Sylva M; Carroll, C Ron

2013-06-01

Shade-grown coffee plantations are often promoted as a conservation strategy for wild birds. However, these agro-ecosystems are actively managed for food production, which may alter bird behaviors or interactions that could change bird health, compared to natural forest. To examine whether there is a difference between the health parameters of wild birds inhabiting shade-grown coffee plantations and natural forest, we evaluated birds in Costa Rica for (1) their general body condition, (2) antibodies to pathogens, (paramyxovirus and Mycoplasma spp.), and (3) the prevalence and diversity of endo-, ecto-, and hemoparasites. We measured exposure to Mycoplasma spp. and paramyxovirus because these are pathogens that could have been introduced with domestic poultry, one mechanism by which these landscapes could be detrimental to wild birds. We captured 1,561 birds representing 75 species. Although seasonal factors influenced body condition, we did not find bird general body condition to be different. A total of 556 birds of 31 species were tested for antibodies against paramyxovirus-1. Of these, five birds tested positive, four of which were from shade coffee. Out of 461 other tests for pathogens (for antibodies and nucleotide detection), none were positive. Pterolichus obtusus, the feather mite of chickens, was found on 15 birds representing two species and all were from shade-coffee plantations. Larvated eggs of Syngamus trachea, a nematode typically associated with chickens, were found in four birds captured in shade coffee and one captured in forest. For hemoparasites, a total of 1,121 blood smears from 68 bird species were examined, and only one species showed a higher prevalence of infection in shade coffee. Our results indicate that shade-coffee plantations do not pose a significant health risk to forest birds, but at least two groups of pathogens may deserve further attention: Haemoproteus spp. and the diversity and identity of endoparasites.

Pose Planning for the Feed Support System of FAST

Directory of Open Access Journals (Sweden)

Rui Yao

2014-01-01

Full Text Available A six-cable driven parallel manipulator and an A-B rotator in the feed support system of the Five-hundred-meter Aperture Spherical radio Telescope (FAST are adopted for realizing the position and pose of nine feeds. The six-cable driven parallel manipulator is a flexible mechanism, which may not be stably controlled due to a small cable tension. The A-B rotator is a rigid mechanism, and its stability and accuracy can be improved by small pose angle. Based on the different characteristics, a pose planning function is presented. The optimization target of the pose planning function is to get the smallest pose angle of the A-B rotator, and the constraint condition can reflect the controllability of the six-cable driven parallel manipulator. Then, the pose planning realization process of the feed support system is proposed. Based on the pose planning method, optimized pose angles of the feed support system for the nine feeds are obtained, which suggests that the pose angle of the six-cable driven parallel manipulator changes from 0° to 14° and the pose angle of the A-B rotator changes from 0° to 26.4°.

2D Methods for pose invariant face recognition

CSIR Research Space (South Africa)

Mokoena, Ntabiseng

2016-12-01

Full Text Available The ability to recognise face images under random pose is a task that is done effortlessly by human beings. However, for a computer system, recognising face images under varying poses still remains an open research area. Face recognition across pose...

The nucleolus is well-posed

Science.gov (United States)

Fragnelli, Vito; Patrone, Fioravante; Torre, Anna

2006-02-01

The lexicographic order is not representable by a real-valued function, contrary to many other orders or preorders. So, standard tools and results for well-posed minimum problems cannot be used. We prove that under suitable hypotheses it is however possible to guarantee the well-posedness of a lexicographic minimum over a compact or convex set. This result allows us to prove that some game theoretical solution concepts, based on lexicographic order are well-posed: in particular, this is true for the nucleolus.

Real-Time Head Pose Estimation on Mobile Platforms

Directory of Open Access Journals (Sweden)

Jianfeng Ren

2010-06-01

Full Text Available Many computer vision applications such as augmented reality require head pose estimation. As far as the real-time implementation of head pose estimation on relatively resource limited mobile platforms is concerned, it is required to satisfy real-time constraints while maintaining reasonable head pose estimation accuracy. The introduced head pose estimation approach in this paper is an attempt to meet this objective. The approach consists of the following components: Viola-Jones face detection, color-based face tracking using an online calibration procedure, and head pose estimation using Hu moment features and Fisher linear discriminant. Experimental results running on an actual mobile device are reported exhibiting both the real- time and accuracy aspects of the developed approach.

Head pose estimation algorithm based on deep learning

Science.gov (United States)

Cao, Yuanming; Liu, Yijun

2017-05-01

Head pose estimation has been widely used in the field of artificial intelligence, pattern recognition and intelligent human-computer interaction and so on. Good head pose estimation algorithm should deal with light, noise, identity, shelter and other factors robustly, but so far how to improve the accuracy and robustness of attitude estimation remains a major challenge in the field of computer vision. A method based on deep learning for pose estimation is presented. Deep learning with a strong learning ability, it can extract high-level image features of the input image by through a series of non-linear operation, then classifying the input image using the extracted feature. Such characteristics have greater differences in pose, while they are robust of light, identity, occlusion and other factors. The proposed head pose estimation is evaluated on the CAS-PEAL data set. Experimental results show that this method is effective to improve the accuracy of pose estimation.

In-the-wild facial expression recognition in extreme poses

Science.gov (United States)

Yang, Fei; Zhang, Qian; Zheng, Chi; Qiu, Guoping

2018-04-01

In the computer research area, facial expression recognition is a hot research problem. Recent years, the research has moved from the lab environment to in-the-wild circumstances. It is challenging, especially under extreme poses. But current expression detection systems are trying to avoid the pose effects and gain the general applicable ability. In this work, we solve the problem in the opposite approach. We consider the head poses and detect the expressions within special head poses. Our work includes two parts: detect the head pose and group it into one pre-defined head pose class; do facial expression recognize within each pose class. Our experiments show that the recognition results with pose class grouping are much better than that of direct recognition without considering poses. We combine the hand-crafted features, SIFT, LBP and geometric feature, with deep learning feature as the representation of the expressions. The handcrafted features are added into the deep learning framework along with the high level deep learning features. As a comparison, we implement SVM and random forest to as the prediction models. To train and test our methodology, we labeled the face dataset with 6 basic expressions.

Face pose tracking using the four-point algorithm

Science.gov (United States)

Fung, Ho Yin; Wong, Kin Hong; Yu, Ying Kin; Tsui, Kwan Pang; Kam, Ho Chuen

2017-06-01

In this paper, we have developed an algorithm to track the pose of a human face robustly and efficiently. Face pose estimation is very useful in many applications such as building virtual reality systems and creating an alternative input method for the disabled. Firstly, we have modified a face detection toolbox called DLib for the detection of a face in front of a camera. The detected face features are passed to a pose estimation method, known as the four-point algorithm, for pose computation. The theory applied and the technical problems encountered during system development are discussed in the paper. It is demonstrated that the system is able to track the pose of a face in real time using a consumer grade laptop computer.

Trans-Pacific ENSO teleconnections pose a correlated risk to global agriculture

Science.gov (United States)

Anderson, W. B.; Seager, R.; Cane, M. A.; Baethgen, W.

2017-12-01

The El Niño Southern Oscillation (ENSO) is a major source of interannual climate variability, particularly in the Pacific Basin. ENSO life-cycles tend to evolve over multiple years, as do the associated trans-Pacific ENSO teleconnections. This analysis, however, represents the first attempt to characterize the structure of the risk posed by ENSO to wheat, maize and soybean production across the Pacific Basin. Our results indicate that most ENSO teleconnections relevant for crop flowering seasons are the result of a single trans-Pacific circulation anomaly that develops in boreal summer and persists through the spring. During the late summer and early fall of a developing ENSO event, the tropical Pacific forces an atmospheric anomaly in the midlatitudes that spans the Pacific Basin. This teleconnection directly links the soybean and maize growing seasons of the US, Mexico and China. It also connects the wheat growing seasons of Argentina, southern Brazil and Australia. The ENSO event peaks in boreal winter, when the atmospheric circulation anomalies intensify and affect maize and soybeans in southeast South America. As the event decays, the ENSO-induced circulation anomalies persist through the wheat flowering seasons in China and the US. While the prospect of ENSO forcing simultaneous droughts in major food producing regions seems disastrous, there may be a silver lining from the perspective of global food security: trans-Pacific ENSO teleconnections to yields are often offsetting between major producing regions in the eastern and western portions of the Pacific Basin. El Niños tend to create good maize and soybean growing conditions in the US and southeast South America, but poor growing conditions in China, Mexico and northeast Brazil. The opposite is true during La Niña. Wheat growing conditions in southeast South America generally have the opposite sign of those in Australia. Finally, we investigate how trade networks interact with this structure of ENSO

Skill Levels of Prospective Physics Teachers on Problem Posing

Science.gov (United States)

Cildir, Sema; Sezen, Nazan

2011-01-01

Problem posing is one of the topics which the educators thoroughly accentuate. Problem posing skill is defined as an introvert activity of a student's learning. In this study, skill levels of prospective physics teachers on problem posing were determined and their views on problem posing were evaluated. To this end, prospective teachers were given…

Antibiotics as CECs: An Overview of the Hazards Posed by Antibiotics and Antibiotic Resistance

Directory of Open Access Journals (Sweden)

Geoffrey Ivan Scott

2016-04-01

Full Text Available ABSTRACTMonitoring programs have traditionally monitored legacy contaminants but are shifting focus to Contaminants of Emerging Concern (CECs. CECs present many challenges for monitoring and assessment, because measurement methods don't always exist nor have toxicological studies been fully conducted to place results in proper context. Also some CECs affect metabolic pathways to produce adverse outcomes that are not assessed through traditional toxicological evaluations. Antibiotics are CECs that pose significant environmental risks including development of both toxic effects at high doses and antibiotic resistance at doses well below the Minimum Inhibitory Concentration (MIC which kill bacteria and have been found in nearly half of all sites monitored in the US. Antimicrobial resistance has generally been attributed to the use of antibiotics in medicine for humans and livestock as well as aquaculture operations. The objective of this study was to assess the extent and magnitude of antibiotics in the environment and estimate their potential hazards in the environment. Antibiotics concentrations were measured in a number of monitoring studies which included Waste Water Treatment Plants (WWTP effluent, surface waters, sediments and biota. A number of studies reported levels of Antibiotic Resistant Microbes (ARM in surface waters and some studies found specific ARM genes (e.g. the blaM-1 gene in E. coli which may pose additional environmental risk. High levels of this gene were found to survive WWTP disinfection and accumulated in sediment at levels 100-1000 times higher than in the sewerage effluent, posing potential risks for gene transfer to other bacteria.in aquatic and marine ecosystems. Antibiotic risk assessment approaches were developed based on the use of MICs and MIC Ratios [High (Antibiotic Resistant/Low (Antibiotic Sensitive MIC] for each antibiotic indicating the range of bacterial adaptability to each antibiotic to help define the No

Xenotropic murine leukemia virus-related virus does not pose a risk to blood recipient safety.

Science.gov (United States)

Dodd, Roger Y; Hackett, John; Linnen, Jeffrey M; Dorsey, Kerri; Wu, Yanyun; Zou, Shimian; Qiu, Xiaoxing; Swanson, Priscilla; Schochetman, Gerald; Gao, Kui; Carrick, James M; Krysztof, David E; Stramer, Susan L

2012-02-01

When xenotropic murine leukemia virus-related virus (XMRV) was first reported in association with chronic fatigue syndrome, it was suggested that it might offer a risk to blood safety. Thus, the prevalence of the virus among blood donors and, if present, its transmissibility by transfusion need to be defined. Two populations of routine blood donor samples (1435 and 13,399) were obtained for prevalence evaluations; samples from a linked donor-recipient repository were also evaluated. Samples were tested for the presence of antibodies to XMRV-related recombinant antigens and/or for XMRV RNA, using validated, high-throughput systems. The presence of antibodies to XMRV could not be confirmed among a total of 17,249 blood donors or recipients (0%; 95% confidence interval [CI], 0%-0.017%); 1763 tested samples were nonreactive for XMRV RNA (0%; 95% CI, 0%-0.17%). Evidence of infection was absent from 109 recipients and 830 evaluable blood samples tested after transfusion of a total of 3741 blood components. XMRV and related murine leukemia virus (MLV) markers are not present among a large population of blood donors and evidence of transfusion transmission could not be detected. Thus, these viruses do not currently pose a threat to blood recipient safety and further actions relating to XMRV and MLV are not justified. © 2012 American Association of Blood Banks.

Local Feature Learning for Face Recognition under Varying Poses

DEFF Research Database (Denmark)

Duan, Xiaodong; Tan, Zheng-Hua

2015-01-01

In this paper, we present a local feature learning method for face recognition to deal with varying poses. As opposed to the commonly used approaches of recovering frontal face images from profile views, the proposed method extracts the subject related part from a local feature by removing the pose...... related part in it on the basis of a pose feature. The method has a closed-form solution, hence being time efficient. For performance evaluation, cross pose face recognition experiments are conducted on two public face recognition databases FERET and FEI. The proposed method shows a significant...... recognition improvement under varying poses over general local feature approaches and outperforms or is comparable with related state-of-the-art pose invariant face recognition approaches. Copyright ©2015 by IEEE....

Person-Independent Head Pose Estimation Using Biased Manifold Embedding

Directory of Open Access Journals (Sweden)

Sethuraman Panchanathan

2008-02-01

Full Text Available Head pose estimation has been an integral problem in the study of face recognition systems and human-computer interfaces, as part of biometric applications. A fine estimate of the head pose angle is necessary and useful for several face analysis applications. To determine the head pose, face images with varying pose angles can be considered to be lying on a smooth low-dimensional manifold in high-dimensional image feature space. However, when there are face images of multiple individuals with varying pose angles, manifold learning techniques often do not give accurate results. In this work, we propose a framework for a supervised form of manifold learning called Biased Manifold Embedding to obtain improved performance in head pose angle estimation. This framework goes beyond pose estimation, and can be applied to all regression applications. This framework, although formulated for a regression scenario, unifies other supervised approaches to manifold learning that have been proposed so far. Detailed studies of the proposed method are carried out on the FacePix database, which contains 181 face images each of 30 individuals with pose angle variations at a granularity of 1∘. Since biometric applications in the real world may not contain this level of granularity in training data, an analysis of the methodology is performed on sparsely sampled data to validate its effectiveness. We obtained up to 2∘ average pose angle estimation error in the results from our experiments, which matched the best results obtained for head pose estimation using related approaches.

To Strike a Pose: No Stereotype Backlash for Power Posing Women

Directory of Open Access Journals (Sweden)

Miriam Rennung

2016-09-01

Full Text Available Power posing, the adoption of open and powerful postures, has effects that parallel those of actual social power. This study explored the social evaluation of adopting powerful versus powerless body postures in men and women regarding perceived warmth, competence, and the likelihood of eliciting admiration, envy, pity, and contempt. Previous findings suggest that the display of power by women may have side effects due to gender stereotyping, namely reduced warmth ratings and negative emotional reactions. An experiment (N = 2,473 asked participants to rate pictures of men and women who adopted high-power or low-power body postures. High-power posers were rated higher on competence, admiration, envy, and contempt compared to low-power posers, whereas the opposite was true for pity. There was no impact of power posing on perceived warmth. Contrary to expectations, the poser’s gender did not moderate any of the effects. These findings suggest that nonverbal displays of power do influence fundamental dimensions of social perception and their accompanying emotional reactions but result in comparably positive and negative evaluations for both genders.

Status of Environmental Management Initiatives to Accelerate the Reduction of Environmental Risks and Challenges Posed by the Legacy of the Cold War

International Nuclear Information System (INIS)

2009-01-01

Fifty years of nuclear weapons production and energy research in the United States during the Cold War generated large amounts of radioactive wastes, spent nuclear fuel (SNF), excess plutonium and uranium, thousands of contaminated facilities, and contaminated soil and groundwater. During most of that half century, the Nation did not have the environmental regulatory structure or nuclear waste cleanup technologies that exist today. The result was a legacy of nuclear waste that was stored and disposed of in ways now considered unacceptable. Cleaning up and ultimately disposing of these wastes is the responsibility of the U.S. Department of Energy (DOE). In 1989, DOE established the Office of Environmental Management (EM) to solve the large scale and technically challenging risks posed by the world's largest nuclear cleanup. This required EM to build a new nuclear cleanup infrastructure, assemble and train a technically specialized workforce, and develop the technologies and tools required to safely decontaminate, disassemble, stabilize, disposition, and remediate unique radiation hazards. The sites where nuclear activities produced legacy waste and contamination include the original Manhattan Project sites--Los Alamos, New Mexico; Hanford, Washington; and Oak Ridge, Tennessee--as well as major Cold War sites, such as Savannah River Site, South Carolina; the Idaho National Laboratory, Idaho; Rocky Flats Plant, Colorado; and Fernald, Ohio. Today EM has responsibility for nuclear cleanup activities at 21 sites covering more than two million acres in 13 states, and employs more than 30,000 Federal and contractor employees, including scientists, engineers and hazardous waste technicians. This cleanup poses unique, technically complex problems, which must be solved under the most hazardous of conditions, and which will require billions of dollars a year for several more decades. The EM program focus during its first 10 years was on managing the most urgent risks and

Status of Environmental Management Initiatives to Accelerate the Reduction of Environmental Risks and Challenges Posed by the Legacy of the Cold War

Energy Technology Data Exchange (ETDEWEB)

None

2009-01-01

Fifty years of nuclear weapons production and energy research in the United States during the Cold War generated large amounts of radioactive wastes, spent nuclear fuel (SNF), excess plutonium and uranium, thousands of contaminated facilities, and contaminated soil and groundwater. During most of that half century, the Nation did not have the environmental regulatory structure or nuclear waste cleanup technologies that exist today. The result was a legacy of nuclear waste that was stored and disposed of in ways now considered unacceptable. Cleaning up and ultimately disposing of these wastes is the responsibility of the U.S. Department of Energy (DOE). In 1989, DOE established the Office of Environmental Management (EM) to solve the large scale and technically challenging risks posed by the world's largest nuclear cleanup. This required EM to build a new nuclear cleanup infrastructure, assemble and train a technically specialized workforce, and develop the technologies and tools required to safely decontaminate, disassemble, stabilize, disposition, and remediate unique radiation hazards. The sites where nuclear activities produced legacy waste and contamination include the original Manhattan Project sites--Los Alamos, New Mexico; Hanford, Washington; and Oak Ridge, Tennessee--as well as major Cold War sites, such as Savannah River Site, South Carolina; the Idaho National Laboratory, Idaho; Rocky Flats Plant, Colorado; and Fernald, Ohio. Today EM has responsibility for nuclear cleanup activities at 21 sites covering more than two million acres in 13 states, and employs more than 30,000 Federal and contractor employees, including scientists, engineers and hazardous waste technicians. This cleanup poses unique, technically complex problems, which must be solved under the most hazardous of conditions, and which will require billions of dollars a year for several more decades. The EM program focus during its first 10 years was on managing the most urgent risks and

Robust head pose estimation via supervised manifold learning.

Science.gov (United States)

Wang, Chao; Song, Xubo

2014-05-01

Head poses can be automatically estimated using manifold learning algorithms, with the assumption that with the pose being the only variable, the face images should lie in a smooth and low-dimensional manifold. However, this estimation approach is challenging due to other appearance variations related to identity, head location in image, background clutter, facial expression, and illumination. To address the problem, we propose to incorporate supervised information (pose angles of training samples) into the process of manifold learning. The process has three stages: neighborhood construction, graph weight computation and projection learning. For the first two stages, we redefine inter-point distance for neighborhood construction as well as graph weight by constraining them with the pose angle information. For Stage 3, we present a supervised neighborhood-based linear feature transformation algorithm to keep the data points with similar pose angles close together but the data points with dissimilar pose angles far apart. The experimental results show that our method has higher estimation accuracy than the other state-of-art algorithms and is robust to identity and illumination variations. Copyright © 2014 Elsevier Ltd. All rights reserved.

Development of a semi-quantitative risk assessment model for evaluating environmental threat posed by the three first EU watch-list pharmaceuticals to urban wastewater treatment plants: An Irish case study.

Science.gov (United States)

Tahar, Alexandre; Tiedeken, Erin Jo; Clifford, Eoghan; Cummins, Enda; Rowan, Neil

2017-12-15

Contamination of receiving waters with pharmaceutical compounds is of pressing concern. This constitutes the first study to report on the development of a semi-quantitative risk assessment (RA) model for evaluating the environmental threat posed by three EU watch list pharmaceutical compounds namely, diclofenac, 17-beta-estradiol and 17-alpha-ethinylestradiol, to aquatic ecosystems using Irish data as a case study. This RA model adopts the Irish Environmental Protection Agency Source-Pathway-Receptor concept to define relevant parameters for calculating low, medium or high risk score for each agglomeration of wastewater treatment plant (WWTP), which include catchment, treatments, operational and management factors. This RA model may potentially be used on a national scale to (i) identify WWTPs that pose a particular risk as regards releasing disproportionally high levels of these pharmaceutical compounds, and (ii) help identify priority locations for introducing or upgrading control measures (e.g. tertiary treatment, source reduction). To assess risks for these substances of emerging concern, the model was applied to 16 urban WWTPs located in different regions in Ireland that were scored for the three different compounds and ranked as low, medium or high risk. As a validation proxy, this case study used limited monitoring data recorded at some these plants receiving waters. It is envisaged that this semi-quantitative RA approach may aid other EU countries investigate and screen for potential risks where limited measured or predicted environmental pollutant concentrations and/or hydrological data are available. This model is semi-quantitative, as other factors such as influence of climate change and drug usage or prescription data will need to be considered in a future point for estimating and predicting risks. Copyright © 2017 Elsevier B.V. All rights reserved.

University Students' Problem Posing Abilities and Attitudes towards Mathematics.

Science.gov (United States)

Grundmeier, Todd A.

2002-01-01

Explores the problem posing abilities and attitudes towards mathematics of students in a university pre-calculus class and a university mathematical proof class. Reports a significant difference in numeric posing versus non-numeric posing ability in both classes. (Author/MM)

Students’ Mathematical Creative Thinking through Problem Posing Learning

Science.gov (United States)

Ulfah, U.; Prabawanto, S.; Jupri, A.

2017-09-01

The research aims to investigate the differences in enhancement of students’ mathematical creative thinking ability of those who received problem posing approach assisted by manipulative media and students who received problem posing approach without manipulative media. This study was a quasi experimental research with non-equivalent control group design. Population of this research was third-grade students of a primary school in Bandung city in 2016/2017 academic year. Sample of this research was two classes as experiment class and control class. The instrument used is a test of mathematical creative thinking ability. Based on the results of the research, it is known that the enhancement of the students’ mathematical creative thinking ability of those who received problem posing approach with manipulative media aid is higher than the ability of those who received problem posing approach without manipulative media aid. Students who get learning problem posing learning accustomed in arranging mathematical sentence become matter of story so it can facilitate students to comprehend about story

Hazardous and Noxious Substances (HNS) in the marine environment: prioritizing HNS that pose major risk in a European context.

Science.gov (United States)

Neuparth, T; Moreira, S; Santos, M M; Reis-Henriques, M A

2011-01-01

Increases in the maritime transportation of Hazardous and Noxious Substances (HNS), alongside the need for an effective response to HNS spills have led environmental managers and the scientific community to focus attention on HNS spill preparedness and responsiveness. In the context of the ARCOPOL project, a weight-of-evidence approach was developed aimed at prioritizing HNS that pose major environmental risks to European waters. This approach takes into consideration the occurrence probability of HNS spills in European Atlantic waters and the severity of exposure associated with their physico-chemical properties and toxicity to marine organisms. Additionally, a screening analysis of the toxicological information available for the prioritization of HNS was performed. Here we discuss the need for a prioritization methodology to select HNS that are likely to cause severe marine environmental effects as an essential step towards the establishment of a more effective preparedness and response to HNS incidents. Copyright © 2010 Elsevier Ltd. All rights reserved.

A conceptual model of the risk of elder abuse posed by incontinence and care dependence.

Science.gov (United States)

Ostaszkiewicz, Joan

2017-12-08

To describe and critically analyse the thinking that led to the concept of an association between incontinence, care dependence and elder abuse. Coercive or abusive continence care practices include chastising a person for their incontinence and overriding their attempts to resist continence care. Neglect in continence care is characterised by withholding or delaying responding to requests for help to maintain continence or to manage incontinence, and restricting a person's access to toileting assistance, incontinence aids or hygiene care. Contemporary biomedical understandings about incontinence and influencing concepts from the fields of sociology, psychology and nursing were analysed to inform the design of a conceptual model that elucidates possible associations between incontinence, care dependence and elder abuse. Ideas generated from an analysis of the concepts led to the development of a model termed the "Model of Attributes to Abuse of Dependent Elders in Continence Care" (MADE-CC). The MADE-CC theorises factors that cause and contribute to abuse in continence care. Carer factors include physical and emotional exhaustion, frustration related to the inability to control or predict incontinence, resentment associated with constraints imposed by care dependence, disgust associated with physical contact with urine/faeces, limited knowledge and skills about incontinence and ethical conflicts concerning care. Care recipient factors include frequent and severe incontinence, cognitive impairment and a history of physical or psychological trauma. Social factors that are theorised include the stigmatised nature of incontinence, social taboos and cultural norms and the private nature of continence care. The MADE-CC illuminates the potential risk of elder abuse posed by incontinence and care dependence. It should be used to improve ethical care of older people and stimulate debate about everyday ethics in the care of older people who are care dependent and to optimise

Manifolds for pose tracking from monocular video

Science.gov (United States)

Basu, Saurav; Poulin, Joshua; Acton, Scott T.

2015-03-01

We formulate a simple human-pose tracking theory from monocular video based on the fundamental relationship between changes in pose and image motion vectors. We investigate the natural embedding of the low-dimensional body pose space into a high-dimensional space of body configurations that behaves locally in a linear manner. The embedded manifold facilitates the decomposition of the image motion vectors into basis motion vector fields of the tangent space to the manifold. This approach benefits from the style invariance of image motion flow vectors, and experiments to validate the fundamental theory show reasonable accuracy (within 4.9 deg of the ground truth).

The lighter side of advertising: investigating posing and lighting biases.

Science.gov (United States)

Thomas, Nicole A; Burkitt, Jennifer A; Patrick, Regan E; Elias, Lorin J

2008-11-01

People tend to display the left cheek when posing for a portrait; however, this effect does not appear to generalise to advertising. The amount of body visible in the image and the sex of the poser might also contribute to the posing bias. Portraits also exhibit lateral lighting biases, with most images being lit from the left. This effect might also be present in advertisements. A total of 2801 full-page advertisements were sampled and coded for posing direction, lighting direction, sex of model, and amount of body showing. Images of females showed an overall leftward posing bias, but the biases in males depended on the amount of body visible. Males demonstrated rightward posing biases for head-only images. Overall, images tended to be lit from the top left corner. The two factors of posing and lighting biases appear to influence one another. Leftward-lit images had more leftward poses than rightward, while the opposite occurred for rightward-lit images. Collectively, these results demonstrate that the posing biases in advertisements are dependent on the amount of body showing in the image, and that biases in lighting direction interact with these posing biases.

Coupled bias-variance tradeoff for cross-pose face recognition.

Science.gov (United States)

Li, Annan; Shan, Shiguang; Gao, Wen

2012-01-01

Subspace-based face representation can be looked as a regression problem. From this viewpoint, we first revisited the problem of recognizing faces across pose differences, which is a bottleneck in face recognition. Then, we propose a new approach for cross-pose face recognition using a regressor with a coupled bias-variance tradeoff. We found that striking a coupled balance between bias and variance in regression for different poses could improve the regressor-based cross-pose face representation, i.e., the regressor can be more stable against a pose difference. With the basic idea, ridge regression and lasso regression are explored. Experimental results on CMU PIE, the FERET, and the Multi-PIE face databases show that the proposed bias-variance tradeoff can achieve considerable reinforcement in recognition performance.

Formulas in inverse and ill-posed problems

CERN Document Server

Anikonov, Yu E

1997-01-01

The Inverse and Ill-Posed Problems Series is a series of monographs publishing postgraduate level information on inverse and ill-posed problems for an international readership of professional scientists and researchers. The series aims to publish works which involve both theory and applications in, e.g., physics, medicine, geophysics, acoustics, electrodynamics, tomography, and ecology.

Space Radiation and Risks to Human Health

Science.gov (United States)

Huff, Janice L.; Patel, Zarana S.; Simonsen, Lisa C.

2014-01-01

The radiation environment in space poses significant challenges to human health and is a major concern for long duration manned space missions. Outside the Earth's protective magnetosphere, astronauts are exposed to higher levels of galactic cosmic rays, whose physical characteristics are distinct from terrestrial sources of radiation such as x-rays and gamma-rays. Galactic cosmic rays consist of high energy and high mass nuclei as well as high energy protons; they impart unique biological damage as they traverse through tissue with impacts on human health that are largely unknown. The major health issues of concern are the risks of radiation carcinogenesis, acute and late decrements to the central nervous system, degenerative tissue effects such as cardiovascular disease, as well as possible acute radiation syndromes due to an unshielded exposure to a large solar particle event. The NASA Human Research Program's Space Radiation Program Element is focused on characterization and mitigation of these space radiation health risks along with understanding these risks in context of the other biological stressors found in the space environment. In this overview, we will provide a description of these health risks and the Element's research strategies to understand and mitigate these risks.

Fast human pose estimation using 3D Zernike descriptors

Science.gov (United States)

Berjón, Daniel; Morán, Francisco

2012-03-01

Markerless video-based human pose estimation algorithms face a high-dimensional problem that is frequently broken down into several lower-dimensional ones by estimating the pose of each limb separately. However, in order to do so they need to reliably locate the torso, for which they typically rely on time coherence and tracking algorithms. Their losing track usually results in catastrophic failure of the process, requiring human intervention and thus precluding their usage in real-time applications. We propose a very fast rough pose estimation scheme based on global shape descriptors built on 3D Zernike moments. Using an articulated model that we configure in many poses, a large database of descriptor/pose pairs can be computed off-line. Thus, the only steps that must be done on-line are the extraction of the descriptors for each input volume and a search against the database to get the most likely poses. While the result of such process is not a fine pose estimation, it can be useful to help more sophisticated algorithms to regain track or make more educated guesses when creating new particles in particle-filter-based tracking schemes. We have achieved a performance of about ten fps on a single computer using a database of about one million entries.

Scientific Opinion on the risks to plant health posed by European versus non-European populations of the potato cyst nematodes Globodera pallida and Globodera rostochiensis

DEFF Research Database (Denmark)

Baker, R.; Candresse, T.; Dormannsné Simon, E.

2012-01-01

The Panel on Plant Health has delivered a scientific opinion on the different risks posed by European and non-European populations of the potato cyst nematodes (PCN) Globodera pallida and Globodera rostochiensis to solanaceous plants in the EU and on the effectiveness of current control measures...... to place of production freedom and soil origin were noted, and the Panel identified additional risk reduction options for certain plants for planting (e.g. bulbs) and additional requirements to confirm the absence of PCN in places of production. The Panel also identified some problems with the existing...... control measures to reduce the spread of PCN within the EU. A thorough and well-coordinated EU-wide survey using standardized methods would be necessary to evaluate the need to maintain these measures. The monitoring of PCN populations should exploit new diagnostic techniques (e.g. mitochondrial DNA...

Preliminary risk assessment database and risk ranking of pharmaceuticals in the environment

International Nuclear Information System (INIS)

Cooper, Emily R.; Siewicki, Thomas C.; Phillips, Karl

2008-01-01

There is increasing concern about pharmaceuticals entering surface waters and the impacts these compounds may have on aquatic organisms. Many contaminants, including pharmaceuticals, are not completely removed by wastewater treatment. Discharge of effluent into surface waters results in chronic low-concentration exposure of aquatic organisms to these compounds, with unknown impacts. Exposure of virulent bacteria in wastewater to antibiotic residues may also induce resistance, which could threaten human health. The purpose of this study was to provide information on pharmaceutical threats to the environment. A preliminary risk assessment database for common pharmaceuticals was created and put into a web-accessible database named 'Pharmaceuticals in the Environment, Information for Assessing Risk' (PEIAR) to help others evaluate potential risks of pharmaceutical contaminants in the environment. Information from PEIAR was used to prioritize compounds that may threaten the environment, with a focus on marine and estuarine environments. The pharmaceuticals were ranked using five different combinations of physical-chemical and toxicological data, which emphasized different risks. The results of the ranking methods differed in the compounds identified as high risk; however, drugs from the central nervous system, cardiovascular, and anti-infective classes were heavily represented within the top 100 drugs in all rankings. Anti-infectives may pose the greatest overall risk based upon our results using a combination of factors that measure environmental transport, fate, and aquatic toxicity. The dataset is also useful for highlighting information that is still needed to assuredly assess risk

[Abuse of energy drinks: does it pose a risk?].

Science.gov (United States)

Petit, Aymeric; Karila, Laurent; Lejoyeux, Michel

2015-03-01

Energy drinks designate "any product in the form of a drink or concentrated liquid containing a mixture of ingredients having the property to raise the level of energy and liveliness". Their introduction has raised many reluctance and reserves after numerous cardiovascular and neurological injuries among regular consumers. This article attempts to synthesize the existing literature on energy drinks. The review focuses to show that excessive energy drinks consumption cause many complications. The literature review was conducted from 2001 to 2014, using PubMed, Google Scholar, EMBASE, and PsycInfo, using the following keywords alone or combined: energy drinks, caffeine, taurine, toxicity, dependence, complications. Occasional or moderate consumption of these cans seem to present little risk to healthy adults. However, their repeated consumption in proportions that far exceed the recommendations for recommended use by the manufacturers, combined with the use of alcohol or illicit drugs consumption increases the risk of occurrence of somatic and psychiatric complications, especially among underage, and subjects with cardiovascular and neurological history. Repeated consumption of energy drinks increases the risk of somatic and psychiatric complications. Further studies must be controlled to improve our understanding of other possible negative consequences on health. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Transfer between Pose and Illumination Training in Face Recognition

Science.gov (United States)

Liu, Chang Hong; Bhuiyan, Md. Al-Amin; Ward, James; Sui, Jie

2009-01-01

The relationship between pose and illumination learning in face recognition was examined in a yes-no recognition paradigm. The authors assessed whether pose training can transfer to a new illumination or vice versa. Results show that an extensive level of pose training through a face-name association task was able to generalize to a new…

An improved silhouette for human pose estimation

Science.gov (United States)

Hawes, Anthony H.; Iftekharuddin, Khan M.

2017-08-01

We propose a novel method for analyzing images that exploits the natural lines of a human poses to find areas where self-occlusion could be present. Errors caused by self-occlusion cause several modern human pose estimation methods to mis-identify body parts, which reduces the performance of most action recognition algorithms. Our method is motivated by the observation that, in several cases, occlusion can be reasoned using only boundary lines of limbs. An intelligent edge detection algorithm based on the above principle could be used to augment the silhouette with information useful for pose estimation algorithms and push forward progress on occlusion handling for human action recognition. The algorithm described is applicable to computer vision scenarios involving 2D images and (appropriated flattened) 3D images.

Pose estimation for mobile robots working on turbine blade

Energy Technology Data Exchange (ETDEWEB)

Ma, X.D.; Chen, Q.; Liu, J.J.; Sun, Z.G.; Zhang, W.Z. [Tsinghua Univ., Beijing (China). Key Laboratory for Advanced Materials Processing Technology, Ministry of Education, Dept. of Mechanical Engineering

2009-03-11

This paper discussed a features point detection and matching task technique for mobile robots used in wind turbine blade applications. The vision-based scheme used visual information from the robot's surrounding environment to match successive image frames. An improved pose estimation algorithm based on a scale invariant feature transform (SIFT) was developed to consider the characteristics of local images of turbine blades, pose estimation problems, and conditions. The method included a pre-subsampling technique for reducing computation and bidirectional matching for improving precision. A random sample consensus (RANSAC) method was used to estimate the robot's pose. Pose estimation conditions included a wide pose range; the distance between neighbouring blades; and mechanical, electromagnetic, and optical disturbances. An experimental platform was used to demonstrate the validity of the proposed algorithm. 20 refs., 6 figs.

Temporal subtraction of chest radiographs compensating pose differences

Science.gov (United States)

von Berg, Jens; Dworzak, Jalda; Klinder, Tobias; Manke, Dirk; Kreth, Adrian; Lamecker, Hans; Zachow, Stefan; Lorenz, Cristian

2011-03-01

Temporal subtraction techniques using 2D image registration improve the detectability of interval changes from chest radiographs. Although such methods are well known for some time they are not widely used in radiologic practice. The reason is the occurrence of strong pose differences between two acquisitions with a time interval of months to years in between. Such strong perspective differences occur in a reasonable number of cases. They cannot be compensated by available image registration methods and thus mask interval changes to be undetectable. In this paper a method is proposed to estimate a 3D pose difference by the adaptation of a 3D rib cage model to both projections. The difference between both is then compensated for, thus producing a subtraction image with virtually no change in pose. The method generally assumes that no 3D image data is available from the patient. The accuracy of pose estimation is validated with chest phantom images acquired under controlled geometric conditions. A subtle interval change simulated by a piece of plastic foam attached to the phantom becomes visible in subtraction images generated with this technique even at strong angular pose differences like an anterior-posterior inclination of 13 degrees.

Non-standard and improperly posed problems

CERN Document Server

Straughan, Brian; Ames, William F

1997-01-01

Written by two international experts in the field, this book is the first unified survey of the advances made in the last 15 years on key non-standard and improperly posed problems for partial differential equations.This reference for mathematicians, scientists, and engineers provides an overview of the methodology typically used to study improperly posed problems. It focuses on structural stability--the continuous dependence of solutions on the initial conditions and the modeling equations--and on problems for which data are only prescribed on part of the boundary.The book addresses continuou

Pose Estimation with a Kinect for Ergonomic Studies: Evaluation of the Accuracy Using a Virtual Mannequin

Directory of Open Access Journals (Sweden)

Pierre Plantard

2015-01-01

Full Text Available Analyzing human poses with a Kinect is a promising method to evaluate potentials risks of musculoskeletal disorders at workstations. In ecological situations, complex 3D poses and constraints imposed by the environment make it difficult to obtain reliable kinematic information. Thus, being able to predict the potential accuracy of the measurement for such complex 3D poses and sensor placements is challenging in classical experimental setups. To tackle this problem, we propose a new evaluation method based on a virtual mannequin. In this study, we apply this method to the evaluation of joint positions (shoulder, elbow, and wrist, joint angles (shoulder and elbow, and the corresponding RULA (a popular ergonomics assessment grid upper-limb score for a large set of poses and sensor placements. Thanks to this evaluation method, more than 500,000 configurations have been automatically tested, which would be almost impossible to evaluate with classical protocols. The results show that the kinematic information obtained by the Kinect software is generally accurate enough to fill in ergonomic assessment grids. However inaccuracy strongly increases for some specific poses and sensor positions. Using this evaluation method enabled us to report configurations that could lead to these high inaccuracies. As a supplementary material, we provide a software tool to help designers to evaluate the expected accuracy of this sensor for a set of upper-limb configurations. Results obtained with the virtual mannequin are in accordance with those obtained from a real subject for a limited set of poses and sensor placements.

Method of orthogonally splitting imaging pose measurement

Science.gov (United States)

Zhao, Na; Sun, Changku; Wang, Peng; Yang, Qian; Liu, Xintong

2018-01-01

In order to meet the aviation's and machinery manufacturing's pose measurement need of high precision, fast speed and wide measurement range, and to resolve the contradiction between measurement range and resolution of vision sensor, this paper proposes an orthogonally splitting imaging pose measurement method. This paper designs and realizes an orthogonally splitting imaging vision sensor and establishes a pose measurement system. The vision sensor consists of one imaging lens, a beam splitter prism, cylindrical lenses and dual linear CCD. Dual linear CCD respectively acquire one dimensional image coordinate data of the target point, and two data can restore the two dimensional image coordinates of the target point. According to the characteristics of imaging system, this paper establishes the nonlinear distortion model to correct distortion. Based on cross ratio invariability, polynomial equation is established and solved by the least square fitting method. After completing distortion correction, this paper establishes the measurement mathematical model of vision sensor, and determines intrinsic parameters to calibrate. An array of feature points for calibration is built by placing a planar target in any different positions for a few times. An terative optimization method is presented to solve the parameters of model. The experimental results show that the field angle is 52 °, the focus distance is 27.40 mm, image resolution is 5185×5117 pixels, displacement measurement error is less than 0.1mm, and rotation angle measurement error is less than 0.15°. The method of orthogonally splitting imaging pose measurement can satisfy the pose measurement requirement of high precision, fast speed and wide measurement range.

[Energy drinks: an unknown risk].

Science.gov (United States)

Petit, Aymeric; Levy, Fanny; Lejoyeux, Michel; Reynaud, Michel; Karila, Laurent

2012-05-01

The term "energy drink" designates "any product in the form of a drink or concentrated liquid, which claims to contain a mixture of ingredients having the property to raise the level of energy and vivacity". The main brands, Red Bull, Dark Dog, Rockstar, Burn, and Monster, are present in food stores, sports venues, and bars among other soft drinks and fruit juices. Their introduction into the French market raised many reluctances, because of the presence of taurine, caffeine and glucuronolactone. These components present in high concentrations, could be responsible for adverse effects on health. The association of energy drinks and spirits is widely found among adolescents and adults who justify drinking these mixed drinks by their desire to drink more alcohol while delaying drunkenness. Given the importance of the number of incidents reported among the energy drinks consumers, it seemed appropriate to make a synthesis of available data and to establish causal links between the use of these products and the development of health complications. For a literature review, we selected scientific articles both in English and French published between 2001 and 2011 by consulting the databases Medline, Embase, PsycINFO and Google Scholar. The words used alone or in combination are "energy dinks", "caffeine", "taurine", "toxicity", "dependence". An occasional to a moderate consumption of these drinks seems to present little risk for healthy adults. However, excessive consumption associated with the use of alcohol or drugs in amounts that far exceed the manufacturers recommended amount, could be responsible for negative consequences on health, particularly among subjects with cardiovascular disease.

Pose estimation of industrial objects towards robot operation

Science.gov (United States)

Niu, Jie; Zhou, Fuqiang; Tan, Haishu; Cao, Yu

2017-10-01

With the advantages of wide range, non-contact and high flexibility, the visual estimation technology of target pose has been widely applied in modern industry, robot guidance and other engineering practices. However, due to the influence of complicated industrial environment, outside interference factors, lack of object characteristics, restrictions of camera and other limitations, the visual estimation technology of target pose is still faced with many challenges. Focusing on the above problems, a pose estimation method of the industrial objects is developed based on 3D models of targets. By matching the extracted shape characteristics of objects with the priori 3D model database of targets, the method realizes the recognition of target. Thus a pose estimation of objects can be determined based on the monocular vision measuring model. The experimental results show that this method can be implemented to estimate the position of rigid objects based on poor images information, and provides guiding basis for the operation of the industrial robot.

Multi-view 3D Human Pose Estimation in Complex Environment

NARCIS (Netherlands)

Hofmann, K.M.; Gavrila, D.M.

2012-01-01

We introduce a framework for unconstrained 3D human upper body pose estimation from multiple camera views in complex environment. Its main novelty lies in the integration of three components: single-frame pose recovery, temporal integration and model texture adaptation. Single-frame pose recovery

Contactless and pose invariant biometric identification using hand surface.

Science.gov (United States)

Kanhangad, Vivek; Kumar, Ajay; Zhang, David

2011-05-01

This paper presents a novel approach for hand matching that achieves significantly improved performance even in the presence of large hand pose variations. The proposed method utilizes a 3-D digitizer to simultaneously acquire intensity and range images of the user's hand presented to the system in an arbitrary pose. The approach involves determination of the orientation of the hand in 3-D space followed by pose normalization of the acquired 3-D and 2-D hand images. Multimodal (2-D as well as 3-D) palmprint and hand geometry features, which are simultaneously extracted from the user's pose normalized textured 3-D hand, are used for matching. Individual matching scores are then combined using a new dynamic fusion strategy. Our experimental results on the database of 114 subjects with significant pose variations yielded encouraging results. Consistent (across various hand features considered) performance improvement achieved with the pose correction demonstrates the usefulness of the proposed approach for hand based biometric systems with unconstrained and contact-free imaging. The experimental results also suggest that the dynamic fusion approach employed in this work helps to achieve performance improvement of 60% (in terms of EER) over the case when matching scores are combined using the weighted sum rule.

Occurrence and ecological risk assessment of emerging organic chemicals in urban rivers

DEFF Research Database (Denmark)

Peng, Fengjiao; Pan, Chang Gui; Zhang, Min

2017-01-01

at the suburb area. A screening-level risk assessment showed that 4-nonylphenol and triclosan (TCS) pose potential risks to aquatic organisms in most sampling sites. For individual taxa, 4-NP may pose risks to various groups of aquatic organisms, while TCS only might pose high risks to algae....

Methods of RVD object pose estimation and experiments

Science.gov (United States)

Shang, Yang; He, Yan; Wang, Weihua; Yu, Qifeng

2007-11-01

Methods of measuring a RVD (rendezvous and docking) cooperative object's pose from monocular and binocular images respectively are presented. The methods solve the initial values first and optimize the object pose parameters by bundle adjustment. In the disturbance-rejecting binocular method, chosen measurement system parameters of one camera's exterior parameters are modified simultaneously. The methods need three or more cooperative target points to measure the object's pose accurately. Experimental data show that the methods converge quickly and stably, provide accurate results and do not need accurate initial values. Even when the chosen measurement system parameters are subjected to some amount of disturbance, the binocular method manages to provide fairly accurate results.

Single-frame 3D human pose recovery from multiple views

NARCIS (Netherlands)

Hofmann, M.; Gavrila, D.M.

2009-01-01

We present a system for the estimation of unconstrained 3D human upper body pose from multi-camera single-frame views. Pose recovery starts with a shape detection stage where candidate poses are generated based on hierarchical exemplar matching in the individual camera views. The hierarchy used in

Turkish Primary School Teachers' Opinions about Problem Posing

Science.gov (United States)

Kilic, Cigdem

2013-01-01

Problem posing is one of the most important topics in a mathematics education. Through problem posing, students gain mathematical abilities and concepts and teachers can evaluate their students and arrange adequate learning environments. The aim of the present study is to investigate Turkish primary school teachers' opinions about problem posing…

Standard diffusive systems are well-posed linear systems

NARCIS (Netherlands)

Matignon, Denis; Zwart, Heiko J.

2004-01-01

The class of well-posed linear systems as introduced by Salamon has become a well-understood class of systems, see e.g. the work of Weiss and the book of Staffans. Many partial partial differential equations with boundary control and point observation can be formulated as a well-posed linear system.

Cellular phones were found to pose no health risks

International Nuclear Information System (INIS)

Puranen, L.

1997-01-01

A cellular phone emits radiation very close to a person's head. Any harmful effects that might arise from the use of cellular phones are being studied carefully, but so far no health risks have been determined. However, the phones may interfere with the operation of electrical devices located close-by, such as a cardiac pacemaker. The biological effects of the microwaves emitted by cellular phones might be based on the resultant higher temperatures in the tissues of the head. Since, even in the worst cases, a cellular phone cannot raise the temperature of tissues by more than some tenths of a degree, no health risks based on thermal effects can be attributed to the use of a cellular phone. No reliable theory has been presented for the non-thermal effects of microwaves. Such effects may exist, however. The studies conducted so far have been unable to show that these effects might be harmful to human health. (orig.)

Pose estimation for augmented reality applications using genetic algorithm.

Science.gov (United States)

Yu, Ying Kin; Wong, Kin Hong; Chang, Michael Ming Yuen

2005-12-01

This paper describes a genetic algorithm that tackles the pose-estimation problem in computer vision. Our genetic algorithm can find the rotation and translation of an object accurately when the three-dimensional structure of the object is given. In our implementation, each chromosome encodes both the pose and the indexes to the selected point features of the object. Instead of only searching for the pose as in the existing work, our algorithm, at the same time, searches for a set containing the most reliable feature points in the process. This mismatch filtering strategy successfully makes the algorithm more robust under the presence of point mismatches and outliers in the images. Our algorithm has been tested with both synthetic and real data with good results. The accuracy of the recovered pose is compared to the existing algorithms. Our approach outperformed the Lowe's method and the other two genetic algorithms under the presence of point mismatches and outliers. In addition, it has been used to estimate the pose of a real object. It is shown that the proposed method is applicable to augmented reality applications.

Posing Problems to Understand Children's Learning of Fractions

Science.gov (United States)

Cheng, Lu Pien

2013-01-01

In this study, ways in which problem posing activities aid our understanding of children's learning of addition of unlike fractions and product of proper fractions was examined. In particular, how a simple problem posing activity helps teachers take a second, deeper look at children's understanding of fraction concepts will be discussed. The…

Evaluation of the pollution and human health risks posed by heavy metals in the atmospheric dust in Ebinur Basin in Northwest China.

Science.gov (United States)

Abuduwailil, Jilili; Zhaoyong, Zhang; Fengqing, Jiang

2015-09-01

Recently, a large amount of research assessing pollution levels and the related health risks posed by atmosphere dust has been undertaken worldwide. However, little work has been done in the oases of the arid regions of Northwest China. In this paper, we studied the pollution and health risks over a year of seven heavy metals in the atmospheric dust of Ebinur Basin, a typical oasis in Northwest China. The results showed the following: (1) The annual amount of atmospheric deposition in Ebinur Basin was 298.23 g m(-2) and the average monthly atmospheric deposition was 25.06 g m(-2). The average and maximum values of the seven heavy metals measured were all below the National Soil Environmental Quality Standards (2nd). (2) Heavy metals of Cu, Cr, and As in the atmospheric deposition mainly originated from the natural geological background, while Zn came from human activity. This study also showed that among the seven measured heavy metals, the ratios of the no-pollution status of Pb, Cd, and Hg were higher than those of others with moderate degrees of pollution also accounting for a certain ratio. (3) The carcinogenic risks from As, Cd, and Cr were all lower than the corresponding standard limit values, and these metals are considered not harmful to the health of the basin. However, there is a relatively high risk of exposure for children from hand-to-mouth intake, which is worthy of attention. This research showed that both human activity and natural factors, such as wind and altitude, influenced the heavy metal contents in the atmospheric dust of the study area. Furthermore, recent human activity in the study area had the most negative influence on the accumulation of the heavy metals and the corresponding health risks, especially for Hg, Pb, and Cd, which is worthy of attention.

Allocating monitoring effort in the face of unknown unknowns

Science.gov (United States)

Wintle, B.A.; Runge, M.C.; Bekessy, S.A.

2010-01-01

There is a growing view that to make efficient use of resources, ecological monitoring should be hypothesis-driven and targeted to address specific management questions. 'Targeted' monitoring has been contrasted with other approaches in which a range of quantities are monitored in case they exhibit an alarming trend or provide ad hoc ecological insights. The second form of monitoring, described as surveillance, has been criticized because it does not usually aim to discern between competing hypotheses, and its benefits are harder to identify a priori. The alternative view is that the existence of surveillance data may enable rapid corroboration of emerging hypotheses or help to detect important 'unknown unknowns' that, if undetected, could lead to catastrophic outcomes or missed opportunities. We derive a model to evaluate and compare the efficiency of investments in surveillance and targeted monitoring. We find that a decision to invest in surveillance monitoring may be defensible if: (1) the surveillance design is more likely to discover or corroborate previously unknown phenomena than a targeted design and (2) the expected benefits (or avoided costs) arising from discovery are substantially higher than those arising from a well-planned targeted design. Our examination highlights the importance of being explicit about the objectives, costs and expected benefits of monitoring in a decision analytic framework. ?? 2010 Blackwell Publishing Ltd/CNRS.

Financial Development and Economic Growth: Known Knowns, Known Unknowns, and Unknown Unknowns

OpenAIRE

Ugo Panizza

2014-01-01

This paper summarizes the main findings of the literature on the relationship between financial and economic development (the known knowns), points to directions for future research (the known unknowns), and then speculates on the third Rumsfeldian category. The known knowns section organizes the empirical literature on finance and growth into three strands: (i) the traditional literature which established the link between finance and growth; (ii) the new literature which qualified some of th...

The unknown risk of vertical transmission in sleeping sickness--a literature review.

Directory of Open Access Journals (Sweden)

Andreas K Lindner

Full Text Available BACKGROUND: Children with human African trypanosomiasis (HAT present with a range of generally non-specific symptoms. Late diagnosis is frequent with often tragic outcomes. Trypanosomes can infect the foetus by crossing the placenta. Unequivocal cases of congenital infection that have been reported include newborn babies of infected mothers who were diagnosed with HAT in the first 5 days of life and children of infected mothers who had never entered an endemic country themselves. METHODS: This review systematically summarizes the literature on the vertical transmission of HAT, to our knowledge for the first time. To approach the broader aspects of the subject, articles considering the epidemiology of childhood HAT and HAT in pregnancy were also included. The HAT guidelines and technical reports of the World Health Organisation, Médecins Sans Frontières, Institut de Recherche pour le Développement, and of one endemic country were reviewed. RESULTS: Publications describing congenital HAT are very limited and consist only of single case reports and small case series. Generally it is assumed to be a rare event, but it has never been systematically investigated. In two publications, it is hypothesized that congenital HAT occurs more often than suspected. Not all guidelines and not all HAT literature mention this transmission route. CONCLUSIONS: The risk of vertical transmission is unknown. Awareness of congenital HAT is insufficient, and as a result opportunities for an early diagnosis in newborns may be missed. All HAT guidelines and local HAT protocols should stress that in endemic areas pregnant women should be systematically checked for HAT and that newborns of HAT infected mothers should be assessed for the disease as soon as possible. Studies on the impact of HAT on fertility and pregnancy and studies on congenital HAT are long overdue.

Association study of multiple antibiotic resistance and virulence: a strategy to assess the extent of risk posed by bacterial population in aquatic environment.

Science.gov (United States)

Singh, Santosh Kumar; Ekka, Roseleen; Mishra, Mitali; Mohapatra, Harapriya

2017-07-01

The present study explored the association between multiple antibiotic resistance (MAR) index and virulence index to determine what percent of environmental antibiotic-resistant (eARB) bacteria could pose threat as potential pathogen. 16srRNA-based sequencing of 113 non-duplicate isolates identified majority of them to be gram negative belonging to Enterobacter, Pseudomonas, Aeromonas, Proteus, Acinetobacter, and Klebsiella. Statistical comparison of MAR indices of the abovementioned genera indicated differences in the median values among the groups (p  Klebsiella = Acinetobacter > Proteus > Aeromonas > Enterobacter. Association between MAR index and virulence index revealed that 25% of isolates in the population under study posed high threat to human/animal or both; out of which 75% isolates belonged to genus Pseudomonas. Based on observations of comparative analysis of the six gram-negative genera, it could be concluded that Pseudomonas isolates from environment pose significantly high threat as potential pathogens while Enterobacter isolates posed no threat.

Point Cloud Based Relative Pose Estimation of a Satellite in Close Range

Directory of Open Access Journals (Sweden)

Lujiang Liu

2016-06-01

Full Text Available Determination of the relative pose of satellites is essential in space rendezvous operations and on-orbit servicing missions. The key problems are the adoption of suitable sensor on board of a chaser and efficient techniques for pose estimation. This paper aims to estimate the pose of a target satellite in close range on the basis of its known model by using point cloud data generated by a flash LIDAR sensor. A novel model based pose estimation method is proposed; it includes a fast and reliable pose initial acquisition method based on global optimal searching by processing the dense point cloud data directly, and a pose tracking method based on Iterative Closest Point algorithm. Also, a simulation system is presented in this paper in order to evaluate the performance of the sensor and generate simulated sensor point cloud data. It also provides truth pose of the test target so that the pose estimation error can be quantified. To investigate the effectiveness of the proposed approach and achievable pose accuracy, numerical simulation experiments are performed; results demonstrate algorithm capability of operating with point cloud directly and large pose variations. Also, a field testing experiment is conducted and results show that the proposed method is effective.

Creativity of Field-dependent and Field-independent Students in Posing Mathematical Problems

Science.gov (United States)

Azlina, N.; Amin, S. M.; Lukito, A.

2018-01-01

This study aims at describing the creativity of elementary school students with different cognitive styles in mathematical problem-posing. The posed problems were assessed based on three components of creativity, namely fluency, flexibility, and novelty. The free-type problem posing was used in this study. This study is a descriptive research with qualitative approach. Data collections were conducted through written task and task-based interviews. The subjects were two elementary students. One of them is Field Dependent (FD) and the other is Field Independent (FI) which were measured by GEFT (Group Embedded Figures Test). Further, the data were analyzed based on creativity components. The results show thatFD student’s posed problems have fulfilled the two components of creativity namely fluency, in which the subject posed at least 3 mathematical problems, and flexibility, in whichthe subject posed problems with at least 3 different categories/ideas. Meanwhile,FI student’s posed problems have fulfilled all three components of creativity, namely fluency, in which thesubject posed at least 3 mathematical problems, flexibility, in which thesubject posed problems with at least 3 different categories/ideas, and novelty, in which the subject posed problems that are purely the result of her own ideas and different from problems they have known.

Is supergravity well-posed?

International Nuclear Information System (INIS)

Isenberg, J.; Bao, D.; Yasskin, P.B.

1983-01-01

One rather fundamental question concerning supergravity remains unresolved: Is supergravity a well-posed field theory? That is, does a set of certain (Cauchy) data specified on some initial spacelike surface determine a unique, causally propagating spacetime solution of the supergravity field equations (at least in some finite neighborhood of the initial surface)? In this paper, the authors give a very brief report on work directed towards answering this question. (Auth.)

Spontaneous and posed facial expression in Parkinson's disease.

Science.gov (United States)

Smith, M C; Smith, M K; Ellgring, H

1996-09-01

Spontaneous and posed emotional facial expressions in individuals with Parkinson's disease (PD, n = 12) were compared with those of healthy age-matched controls (n = 12). The intensity and amount of facial expression in PD patients were expected to be reduced for spontaneous but not posed expressions. Emotional stimuli were video clips selected from films, 2-5 min in duration, designed to elicit feelings of happiness, sadness, fear, disgust, or anger. Facial movements were coded using Ekman and Friesen's (1978) Facial Action Coding System (FACS). In addition, participants rated their emotional experience on 9-point Likert scales. The PD group showed significantly less overall facial reactivity than did controls when viewing the films. The predicted Group X Condition (spontaneous vs. posed) interaction effect on smile intensity was found when PD participants with more severe disease were compared with those with milder disease and with controls. In contrast, ratings of emotional experience were similar for both groups. Depression was positively associated with emotion rating but not with measures of facial activity. Spontaneous facial expression appears to be selectively affected in PD, whereas posed expression and emotional experience remain relatively intact.

Neuroendocrine Cell Carcinoma of Unknown Primary Arising in Long Standing History of Multiple Sclerosis

Directory of Open Access Journals (Sweden)

Stergios Boussios

2015-01-01

Full Text Available Multiple sclerosis (MS is a chronic autoimmune disease that targets myelinated axons in the central nervous system (CNS. Cancer of unknown primary site (CUP is a well-recognised clinical disorder, accounting for 3–5% of all malignant epithelial tumors. CUP is clinically characterised as an aggressive disease with early dissemination. Studies of cancer risk in MS patients have shown inconsistent findings. An increased risk of malignancy in patients with MS has been suggested, but recently serious questions have been raised regarding this association. Use of disease-modifying therapies might contribute to an increased cancer risk in selected MS patients. The concurrence of MS and CUP is exceptionally rare. Here we describe the case of a neuroendocrine carcinoma of unknown primary diagnosed in a male patient with a nine-year history of MS. The discussion includes data from all available population-based register studies with estimates of certain malignancies in patients with MS.

Pose-Invariant Face Recognition via RGB-D Images.

Science.gov (United States)

Sang, Gaoli; Li, Jing; Zhao, Qijun

2016-01-01

Three-dimensional (3D) face models can intrinsically handle large pose face recognition problem. In this paper, we propose a novel pose-invariant face recognition method via RGB-D images. By employing depth, our method is able to handle self-occlusion and deformation, both of which are challenging problems in two-dimensional (2D) face recognition. Texture images in the gallery can be rendered to the same view as the probe via depth. Meanwhile, depth is also used for similarity measure via frontalization and symmetric filling. Finally, both texture and depth contribute to the final identity estimation. Experiments on Bosphorus, CurtinFaces, Eurecom, and Kiwi databases demonstrate that the additional depth information has improved the performance of face recognition with large pose variations and under even more challenging conditions.

Perspective projection for variance pose face recognition from camera calibration

Science.gov (United States)

Fakhir, M. M.; Woo, W. L.; Chambers, J. A.; Dlay, S. S.

2016-04-01

Variance pose is an important research topic in face recognition. The alteration of distance parameters across variance pose face features is a challenging. We provide a solution for this problem using perspective projection for variance pose face recognition. Our method infers intrinsic camera parameters of the image which enable the projection of the image plane into 3D. After this, face box tracking and centre of eyes detection can be identified using our novel technique to verify the virtual face feature measurements. The coordinate system of the perspective projection for face tracking allows the holistic dimensions for the face to be fixed in different orientations. The training of frontal images and the rest of the poses on FERET database determine the distance from the centre of eyes to the corner of box face. The recognition system compares the gallery of images against different poses. The system initially utilises information on position of both eyes then focuses principally on closest eye in order to gather data with greater reliability. Differentiation between the distances and position of the right and left eyes is a unique feature of our work with our algorithm outperforming other state of the art algorithms thus enabling stable measurement in variance pose for each individual.

Multi-Task Convolutional Neural Network for Pose-Invariant Face Recognition

Science.gov (United States)

Yin, Xi; Liu, Xiaoming

2018-02-01

This paper explores multi-task learning (MTL) for face recognition. We answer the questions of how and why MTL can improve the face recognition performance. First, we propose a multi-task Convolutional Neural Network (CNN) for face recognition where identity classification is the main task and pose, illumination, and expression estimations are the side tasks. Second, we develop a dynamic-weighting scheme to automatically assign the loss weight to each side task, which is a crucial problem in MTL. Third, we propose a pose-directed multi-task CNN by grouping different poses to learn pose-specific identity features, simultaneously across all poses. Last but not least, we propose an energy-based weight analysis method to explore how CNN-based MTL works. We observe that the side tasks serve as regularizations to disentangle the variations from the learnt identity features. Extensive experiments on the entire Multi-PIE dataset demonstrate the effectiveness of the proposed approach. To the best of our knowledge, this is the first work using all data in Multi-PIE for face recognition. Our approach is also applicable to in-the-wild datasets for pose-invariant face recognition and achieves comparable or better performance than state of the art on LFW, CFP, and IJB-A datasets.

Designing towards the unknown

DEFF Research Database (Denmark)

Wilde, Danielle; Underwood, Jenny

2018-01-01

the research potential to far-ranging possibilities. In this article we unpack the motivations driving the PKI project. We present our mixed-methodology, which entangles textile crafts, design interactions and materiality to shape an embodied enquiry. Our research outcomes are procedural and methodological......New materials with new capabilities demand new ways of approaching design. Destabilising existing methods is crucial to develop new methods. Yet, radical destabilisation—where outcomes remain unknown long enough that new discoveries become possible—is not easy in technology design where complex......, to design towards unknown outcomes, using unknown materials. The impossibility of this task is proving as useful as it is disruptive. At its most potent, it is destabilising expectations, aesthetics and processes. Keeping the researchers, collaborators and participants in a state of unknowing, is opening...

Recension: Mao - The Unknown Story

DEFF Research Database (Denmark)

Clausen, Søren

2005-01-01

Anmeldelse - kritisk! - til Sveriges førende Kinatidsskrift af Jung Chang & Jon Halliday's sensationelle "Mao - the Unknown Story".......Anmeldelse - kritisk! - til Sveriges førende Kinatidsskrift af Jung Chang & Jon Halliday's sensationelle "Mao - the Unknown Story"....

Use of newer technologies with existing service for family reintegration of unknown psychiatric patients: A case series.

Science.gov (United States)

Gowda, Guru S; Telang, Ashay; Sharath, Chandra Reddy; Issac, Thomas Gregor; Haripriya, Chintala; Ramu, Praveen Shivalli; Math, Suresh Bada

2017-10-29

Homeless Mentally Ill (HMI) patients pose a challenge in treatment, management and rehabilitation services. HMI patients are often difficult to engage in treatment, and associated with relapse and rehospitalization, even after recovery. Family plays an important role in treatment engagement and care of the mentally ill person in India. Here, we report two unknown psychiatric patients who were reintegrated to their families using newer technologies with existing service. Newer technologies have helped in early identification of HMI families and reintegration into them. The early reintegration reduced the unnecessary detention of HMI patients inside the hospital after recovery. Copyright © 2017 Elsevier B.V. All rights reserved.

Numerical methods for the design of large-scale nonlinear discrete ill-posed inverse problems

International Nuclear Information System (INIS)

Haber, E; Horesh, L; Tenorio, L

2010-01-01

Design of experiments for discrete ill-posed problems is a relatively new area of research. While there has been some limited work concerning the linear case, little has been done to study design criteria and numerical methods for ill-posed nonlinear problems. We present an algorithmic framework for nonlinear experimental design with an efficient numerical implementation. The data are modeled as indirect, noisy observations of the model collected via a set of plausible experiments. An inversion estimate based on these data is obtained by a weighted Tikhonov regularization whose weights control the contribution of the different experiments to the data misfit term. These weights are selected by minimization of an empirical estimate of the Bayes risk that is penalized to promote sparsity. This formulation entails a bilevel optimization problem that is solved using a simple descent method. We demonstrate the viability of our design with a problem in electromagnetic imaging based on direct current resistivity and magnetotelluric data

Chronic kidney disease of unknown etiology in agricultural communities.

Science.gov (United States)

Almaguer, Miguel; Herrera, Raúl; Orantes, Carlos M

2014-04-01

In recent years, Central America, Egypt, India and Sri Lanka have reported a high prevalence of chronic kidney disease of unknown etiology in agricultural communities, predominantly among male farmworkers. This essay examines the disease's case definitions, epidemiology (disease burden, demographics, associated risk factors) and causal hypotheses, by reviewing published findings from El Salvador, Nicaragua, Costa Rica, Sri Lanka, Egypt and India. The range of confirmed chronic kidney disease prevalence was 17.9%-21.1%. Prevalence of reduced glomerular filtration (homemade alcohol use and family history of chronic kidney disease. There is no strong evidence for a single cause, and multiple environmental, occupational and social factors are probably involved. Further etiological research is needed, plus interventions to reduce preventable risk factors.

Evaluating the risks of clinical research: direct comparative analysis.

Science.gov (United States)

Rid, Annette; Abdoler, Emily; Roberson-Nay, Roxann; Pine, Daniel S; Wendler, David

2014-09-01

Many guidelines and regulations allow children and adolescents to be enrolled in research without the prospect of clinical benefit when it poses minimal risk. However, few systematic methods exist to determine when research risks are minimal. This situation has led to significant variation in minimal risk judgments, raising concern that some children are not being adequately protected. To address this concern, we describe a new method for implementing the widely endorsed "risks of daily life" standard for minimal risk. This standard defines research risks as minimal when they do not exceed the risks posed by daily life activities or routine examinations. This study employed a conceptual and normative analysis, and use of an illustrative example. Different risks are composed of the same basic elements: Type, likelihood, and magnitude of harm. Hence, one can compare the risks of research and the risks of daily life by comparing the respective basic elements with each other. We use this insight to develop a systematic method, direct comparative analysis, for implementing the "risks of daily life" standard for minimal risk. The method offers a way of evaluating research procedures that pose the same types of risk as daily life activities, such as the risk of experiencing anxiety, stress, or other psychological harm. We thus illustrate how direct comparative analysis can be applied in practice by using it to evaluate whether the anxiety induced by a respiratory CO2 challenge poses minimal or greater than minimal risks in children and adolescents. Direct comparative analysis is a systematic method for applying the "risks of daily life" standard for minimal risk to research procedures that pose the same types of risk as daily life activities. It thereby offers a method to protect children and adolescents in research, while ensuring that important studies are not blocked because of unwarranted concerns about research risks.

Driver head pose tracking with thermal camera

Science.gov (United States)

Bole, S.; Fournier, C.; Lavergne, C.; Druart, G.; Lépine, T.

2016-09-01

Head pose can be seen as a coarse estimation of gaze direction. In automotive industry, knowledge about gaze direction could optimize Human-Machine Interface (HMI) and Advanced Driver Assistance Systems (ADAS). Pose estimation systems are often based on camera when applications have to be contactless. In this paper, we explore uncooled thermal imagery (8-14μm) for its intrinsic night vision capabilities and for its invariance versus lighting variations. Two methods are implemented and compared, both are aided by a 3D model of the head. The 3D model, mapped with thermal texture, allows to synthesize a base of 2D projected models, differently oriented and labeled in yaw and pitch. The first method is based on keypoints. Keypoints of models are matched with those of the query image. These sets of matchings, aided with the 3D shape of the model, allow to estimate 3D pose. The second method is a global appearance approach. Among all 2D models of the base, algorithm searches the one which is the closest to the query image thanks to a weighted least squares difference.

A Support System for the Electric Appliance Control Using Pose Recognition

Science.gov (United States)

Kawano, Takuya; Yamamoto, Kazuhiko; Kato, Kunihito; Hongo, Hitoshi

In this paper, we propose an electric appliance control support system for aged and bedridden people using pose recognition. We proposed a pose recognition system that distinguishes between seven poses of the user on the bed. First, the face and arm regions of the user are detected by using the skin color. Our system focuses a recognition region surrounding the face region. Next, the higher order local autocorrelation features within the region are extracted. The linear discriminant analysis creates the coefficient matrix that can optimally distinguish among training data from the seven poses. Our algorithm can recognize the seven poses even if the subject wears different clothes and slightly shifts or slants on the bed. From the experimental results, our system achieved an accuracy rate of over 99 %. Then, we show that it possibles to construct one of a user-friendly system.

Flexible Polyhedral Surfaces with Two Flat Poses

Directory of Open Access Journals (Sweden)

Hellmuth Stachel

2015-05-01

Full Text Available We present three types of polyhedral surfaces, which are continuously flexible and have not only an initial pose, where all faces are coplanar, but pass during their self-motion through another pose with coplanar faces (“flat pose”. These surfaces are examples of so-called rigid origami, since we only admit exact flexions, i.e., each face remains rigid during the motion; only the dihedral angles vary. We analyze the geometry behind Miura-ori and address Kokotsakis’ example of a flexible tessellation with the particular case of a cyclic quadrangle. Finally, we recall Bricard’s octahedra of Type 3 and their relation to strophoids.

Coupled multiview autoencoders with locality sensitivity for three-dimensional human pose estimation

Science.gov (United States)

Yu, Jialin; Sun, Jifeng; Luo, Shasha; Duan, Bichao

2017-09-01

Estimating three-dimensional (3D) human poses from a single camera is usually implemented by searching pose candidates with image descriptors. Existing methods usually suppose that the mapping from feature space to pose space is linear, but in fact, their mapping relationship is highly nonlinear, which heavily degrades the performance of 3D pose estimation. We propose a method to recover 3D pose from a silhouette image. It is based on the multiview feature embedding (MFE) and the locality-sensitive autoencoders (LSAEs). On the one hand, we first depict the manifold regularized sparse low-rank approximation for MFE and then the input image is characterized by a fused feature descriptor. On the other hand, both the fused feature and its corresponding 3D pose are separately encoded by LSAEs. A two-layer back-propagation neural network is trained by parameter fine-tuning and then used to map the encoded 2D features to encoded 3D poses. Our LSAE ensures a good preservation of the local topology of data points. Experimental results demonstrate the effectiveness of our proposed method.

Inverse and Ill-posed Problems Theory and Applications

CERN Document Server

Kabanikhin, S I

2011-01-01

The text demonstrates the methods for proving the existence (if et all) and finding of inverse and ill-posed problems solutions in linear algebra, integral and operator equations, integral geometry, spectral inverse problems, and inverse scattering problems. It is given comprehensive background material for linear ill-posed problems and for coefficient inverse problems for hyperbolic, parabolic, and elliptic equations. A lot of examples for inverse problems from physics, geophysics, biology, medicine, and other areas of application of mathematics are included.

Real-time Pipeline for Object Modeling and Grasping Pose Selection via Superquadric Functions

Directory of Open Access Journals (Sweden)

Giulia Vezzani

2017-11-01

Full Text Available This work provides a novel real-time pipeline for modeling and grasping of unknown objects with a humanoid robot. Such a problem is of great interest for the robotic community, since conventional approaches fail when the shape, dimension, or pose of the objects are missing. Our approach reconstructs in real-time a model for the object under consideration and represents the robot hand both with proper and mathematically usable models, i.e., superquadric functions. The volume graspable by the hand is represented by an ellipsoid and is defined a priori, because the shape of the hand is known in advance. The superquadric representing the object is obtained in real-time from partial vision information instead, e.g., one stereo view of the object under consideration, and provides an approximated 3D full model. The optimization problem we formulate for the grasping pose computation is solved online by using the Ipopt software package and, thus, does not require off-line computation or learning. Even though our approach is for a generic humanoid robot, we developed a complete software architecture for executing this approach on the iCub humanoid robot. Together with that, we also provide a tutorial on how to use this framework. We believe that our work, together with the available code, is of a strong utility for the iCub community for three main reasons: object modeling and grasping are relevant problems for the robotic community, our code can be easily applied on every iCub, and the modular structure of our framework easily allows extensions and communications with external code.

Cybersecurity Risks: Are They Inflated?

Directory of Open Access Journals (Sweden)

Petr Chrapavy

2016-05-01

Full Text Available With various views being posed on cybersecurity, this paper examines the proposition that cybersecurity risks are inflated. Due to the complexity of the cybersecurity environment, the risks will be dichotomised into two distinct categories—those posed by cybercrime, and those classified as cyber-warfare. In relation to cyber-crime, the paper examines the rise of cyber-crime, its costs, and the views of these factors by “alarmists” and “sceptics.” In relation to cyber-war, the paper sets aside the emotive issue of the consequences and focuses on the likelihood of a catastrophic attack. The paper concludes that the risk of cyber-crime is real, but the sometimes mooted existential threat poses by cyber-war is inflated. The paper argues that it is important for cyber defences to improve in line with the risks, and to do this, researchers need to work across both categories of cybersecurity.

Trajectory Planning with Pose Feedback for a Dual-Arm Space Robot

Directory of Open Access Journals (Sweden)

Yicheng Liu

2016-01-01

Full Text Available In order to obtain high precision path tracking for a dual-arm space robot, a trajectory planning method with pose feedback is proposed to be introduced into the design process in this paper. Firstly, pose error kinematic models are derived from the related kinematics and desired pose command for the end-effector and the base, respectively. On this basis, trajectory planning with pose feedback is proposed from a control perspective. Theoretical analyses show that the proposed trajectory planning algorithm can guarantee that pose error converges to zero exponentially for both the end-effector and the base when the robot is out of singular configuration. Compared with the existing algorithms, the proposed algorithm can lead to higher precision path tracking for the end-effector. Furthermore, the algorithm renders the system good anti-interference property for the base. Simulation results demonstrate the effectiveness of the proposed trajectory planning algorithm.

Spatial and temporal ecological risk assessment of unionized ammonia nitrogen in Tai Lake, China (2004-2015).

Science.gov (United States)

Li, Yabing; Xu, Elvis Genbo; Liu, Wei; Chen, Yi; Liu, Hongling; Li, Di; Liu, Zhengtao; Giesy, John P; Yu, Hongxia

2017-06-01

Ammonia toxicity varies largely due to its pH- and temperature-dependent speciation (unionized ammonia nitrogen, NH 3 -N). The seasonal and long-term trend of ammonia risk in ecologically significant sections of Tai Lake, China was unknown. In this study, a two-level (deterministic and quantitative) method was developed to assess the special ecological risks posed by NH 3 -N at 37 sites during two seasons (February and September) of 2014 in Tai Lake. The long-term temporal (2004-2015) risk posed by NH 3 -N was also assessed by comparing annual quantitative risk values (probability of exceeding acute or chronic threshold values) in three key sections of Tai Lake. The results indicated the species living in the Tai Lake were at a 0.04% and 32.45% chance of risk due to acute exposure, and a 1.97% and 92.05% chance of risk due to chronic exposure in February and September of 2014, respectively. Alarmingly, the chronic ecological risks of NH 3 -N in the Lanshanzui section of the Tai Lake remained >30% from 2004 to 2011. The chronic risk of NH 3 -N in all three key sections of Tai Lake started to decrease in 2011. This was likely the consequence of the control practice of eutrophication implemented in the Tai Lake. A significant decline in diversity of the benthic invertebrate community of the Tai Lake could be associated with continuous exposure to ammonia over decades given different sensitivity of taxa to ammonia. The results laid a scientific foundation for risk assessment and management of ammonia in Tai Lake, China, and the developed two-level risk assessment approach can also be applied to other similar aquatic regions. Copyright © 2017 Elsevier Inc. All rights reserved.

Determining the Performances of Pre-Service Primary School Teachers in Problem Posing Situations

Science.gov (United States)

Kilic, Cigdem

2013-01-01

This study examined the problem posing strategies of pre-service primary school teachers in different problem posing situations (PPSs) and analysed the issues they encounter while posing problems. A problem posing task consisting of six PPSs (two free, two structured, and two semi-structured situations) was delivered to 40 participants.…

Tooth display and lip position during spontaneous and posed smiling in adults.

Science.gov (United States)

Van Der Geld, Pieter; Oosterveld, Paul; Berge, Stefaan J; Kuijpers-Jagtman, Anne M

2008-08-01

To analyze differences in tooth display, lip-line height, and smile width between the posed smiling record, traditionally produced for orthodontic diagnosis, and the spontaneous (Duchenne) smile of joy. The faces of 122 male participants were each filmed during spontaneous and posed smiling. Spontaneous smiles were elicited through the participants watching a comical movie. Maxillary and mandibular lip-line heights, tooth display, and smile width were measured using a digital videographic method for smile analysis. Paired sample t-tests were used to compare measurements of posed and spontaneous smiling. Maxillary lip-line heights during spontaneous smiling were significantly higher than during posed smiling. Compared to spontaneous smiling, tooth display in the (pre)molar area during posed smiling decreased by up to 30%, along with a significant reduction of smile width. During posed smiling, also mandibular lip-line heights changed and the teeth were more covered by the lower lip than during spontaneous smiling. Reduced lip-line heights, tooth display, and smile width on a posed smiling record can have implications for the diagnostics of lip-line height, smile arc, buccal corridors, and plane of occlusion. Spontaneous smiling records next to posed smiling records are therefore recommended for diagnostic purposes. Because of the dynamic nature of spontaneous smiling, it is proposed to switch to dynamic video recording of the smile.

Invasion risks posed by ornamental freshwater fish trade to southeastern Brazilian rivers

Directory of Open Access Journals (Sweden)

André Lincoln Barroso de Magalhães

, P. reticulata, and Amatitlania nigrofasciata can potentially invade the Todos os Santos River. Six recommendations are suggested to reduce the invasion risk of non-native fish on the rivers surveyed posed by aquarium trade.Um modelo foi desenvolvido para avaliar o risco de invasão de peixes ornamentais não-nativos em seis rios do estado de Minas Gerais, sudeste do Brasil, com foco na popularidade das espécies. Trinta e nove lojas de aquário em seis cidades foram visitadas mensalmente de janeiro a dezembro de 2007. Em cada cidade, as espécies foram identificadas e suas biologias e histórias de invasão foram obtidas da literatura. Calculou-se a frequência de ocorrência anual e quantidade média mensal de exemplares disponíveis nas lojas. Foram obtidas temperaturas trimestrais da água e dados de oxigênio dissolvido de 1997 a 2007 dos rios Velhas, Muriaé, Uberabinha, Sapucaí-Mirim, Doce e Todos os Santos a partir de bases de dados públicas. O risco de invasão de cada espécie foi avaliado através de um modelo composto por nove parâmetros agrupados em quatro variáveis: (i Invasividade (limite de alcance térmico/oxigênio dissolvido, dieta, cuidado parental ou fecundidade, (ii Histórico de invasões (estabelecimento, (iii Pressão de propágulos (sucesso comercial, composto pela frequência de ocorrência anual e número de exemplares disponíveis mensalmente nas lojas, e (iv Invasibilidade (temperatura da água/oxigênio dissolvido dos rios compatível com o limite de alcance térmico/ oxigênio dissolvido das espécies. Das 345 espécies de peixes ornamentais para venda, 332 são não-nativos para Minas Gerais (n = 151 ou Brasil (n = 194. Com base nos valores de corte propostos, cinco espécies de peixes ornamentais não-nativos (Cyprinus rubrofuscus, Carassius auratus, Xiphophorus hellerii, Poecilia reticulata e P. latipinna podem potencialmente invadir os rios Velhas e Muriaé, quatro espécies (C. rubrofuscus, C. auratus, X. helleri, P

What risks do herbal products pose to the Australian community?

Science.gov (United States)

Byard, Roger W; Musgrave, Ian; Maker, Garth; Bunce, Michael

2017-02-06

Traditional herbal products are widely used in Australia to treat a broad range of conditions and diseases. It is popularly believed that these products are safer than prescribed drugs. While many may be safe, it is worrying that the specific effects and harmful interactions of a number of their components with prescription medications is not well understood. Some traditional herbal preparations contain heavy metals and toxic chemicals, as well as naturally occurring organic toxins. The effects of these substances can be dire, including acute hepatic and renal failure, exacerbation of pre-existing conditions and diseases, and even death. The content and quality of herbal preparations are not tightly controlled, with some ingredients either not listed or their concentrations recorded inaccurately on websites or labels. Herbal products may also include illegal ingredients, such as ephedra, Asarum europaeum (European wild ginger) and endangered animal species (eg, snow leopard). An additional problem is augmentation with prescription medications to enhance the apparent effectiveness of a preparation. Toxic substances may also be deliberately or inadvertently added: less expensive, more harmful plants may be substituted for more expensive ingredients, and processing may not be adequate. The lack of regulation and monitoring of traditional herbal preparations in Australia and other Western countries means that their contribution to illness and death is unknown. We need to raise awareness of these problems with health care practitioners and with the general public.

Head Pose Estimation Using Multilinear Subspace Analysis for Robot Human Awareness

Science.gov (United States)

Ivanov, Tonislav; Matthies, Larry; Vasilescu, M. Alex O.

2009-01-01

Mobile robots, operating in unconstrained indoor and outdoor environments, would benefit in many ways from perception of the human awareness around them. Knowledge of people's head pose and gaze directions would enable the robot to deduce which people are aware of the its presence, and to predict future motions of the people for better path planning. To make such inferences, requires estimating head pose on facial images that are combination of multiple varying factors, such as identity, appearance, head pose, and illumination. By applying multilinear algebra, the algebra of higher-order tensors, we can separate these factors and estimate head pose regardless of subject's identity or image conditions. Furthermore, we can automatically handle uncertainty in the size of the face and its location. We demonstrate a pipeline of on-the-move detection of pedestrians with a robot stereo vision system, segmentation of the head, and head pose estimation in cluttered urban street scenes.

Pose-invariant face recognition using Markov random fields.

Science.gov (United States)

Ho, Huy Tho; Chellappa, Rama

2013-04-01

One of the key challenges for current face recognition techniques is how to handle pose variations between the probe and gallery face images. In this paper, we present a method for reconstructing the virtual frontal view from a given nonfrontal face image using Markov random fields (MRFs) and an efficient variant of the belief propagation algorithm. In the proposed approach, the input face image is divided into a grid of overlapping patches, and a globally optimal set of local warps is estimated to synthesize the patches at the frontal view. A set of possible warps for each patch is obtained by aligning it with images from a training database of frontal faces. The alignments are performed efficiently in the Fourier domain using an extension of the Lucas-Kanade algorithm that can handle illumination variations. The problem of finding the optimal warps is then formulated as a discrete labeling problem using an MRF. The reconstructed frontal face image can then be used with any face recognition technique. The two main advantages of our method are that it does not require manually selected facial landmarks or head pose estimation. In order to improve the performance of our pose normalization method in face recognition, we also present an algorithm for classifying whether a given face image is at a frontal or nonfrontal pose. Experimental results on different datasets are presented to demonstrate the effectiveness of the proposed approach.

Pose Estimation and Adaptive Robot Behaviour for Human-Robot Interaction

DEFF Research Database (Denmark)

Svenstrup, Mikael; Hansen, Søren Tranberg; Andersen, Hans Jørgen

2009-01-01

Abstract—This paper introduces a new method to determine a person’s pose based on laser range measurements. Such estimates are typically a prerequisite for any human-aware robot navigation, which is the basis for effective and timeextended interaction between a mobile robot and a human. The robot......’s pose. The resulting pose estimates are used to identify humans who wish to be approached and interacted with. The interaction motion of the robot is based on adaptive potential functions centered around the person that respect the persons social spaces. The method is tested in experiments...

Laparoscopic cholecystectomy poses physical injury risk to surgeons: analysis of hand technique and standing position.

Science.gov (United States)

Youssef, Yassar; Lee, Gyusung; Godinez, Carlos; Sutton, Erica; Klein, Rosemary V; George, Ivan M; Seagull, F Jacob; Park, Adrian

2011-07-01

This study compares surgical techniques and surgeon's standing position during laparoscopic cholecystectomy (LC), investigating each with respect to surgeons' learning, performance, and ergonomics. Little homogeneity exists in LC performance and training. Variations in standing position (side-standing technique vs. between-standing technique) and hand technique (one-handed vs. two-handed) exist. Thirty-two LC procedures performed on a virtual reality simulator were video-recorded and analyzed. Each subject performed four different procedures: one-handed/side-standing, one-handed/between-standing, two-handed/side-standing, and two-handed/between-standing. Physical ergonomics were evaluated using Rapid Upper Limb Assessment (RULA). Mental workload assessment was acquired with the National Aeronautics and Space Administration-Task Load Index (NASA-TLX). Virtual reality (VR) simulator-generated performance evaluation and a subjective survey were analyzed. RULA scores were consistently lower (indicating better ergonomics) for the between-standing technique and higher (indicating worse ergonomics) for the side-standing technique, regardless of whether one- or two-handed. Anatomical scores overall showed side-standing to have a detrimental effect on the upper arms and trunk. The NASA-TLX showed significant association between the side-standing position and high physical demand, effort, and frustration (p<0.05). The two-handed technique in the side-standing position required more effort than the one-handed (p<0.05). No difference in operative time or complication rate was demonstrated among the four procedures. The two-handed/between-standing method was chosen as the best procedure to teach and standardize. Laparoscopic cholecystectomy poses a risk of physical injury to the surgeon. As LC is currently commonly performed in the United States, the left side-standing position may lead to increased physical demand and effort, resulting in ergonomically unsound conditions for

Uniqueness and reconstruction of an unknown semilinear term in a time-fractional reaction–diffusion equation

KAUST Repository

Luchko, Yuri

2013-05-30

In this paper, we consider a reaction-diffusion problem with an unknown nonlinear source function that has to be determined from overposed data. The underlying model is in the form of a time-fractional reaction-diffusion equation and the work generalizes some known results for the inverse problems posed for PDEs of parabolic type. For the inverse problem under consideration, a uniqueness result is proved and a numerical algorithm with some theoretical qualification is presented in the one-dimensional case. The key both to the uniqueness result and to the numerical algorithm relies on the maximum principle which has recently been shown to hold for the fractional diffusion equation. In order to show the effectiveness of the proposed method, results of numerical simulations are presented. © 2013 IOP Publishing Ltd.

Locating binding poses in protein-ligand systems using reconnaissance metadynamics

Science.gov (United States)

Söderhjelm, Pär; Tribello, Gareth A.; Parrinello, Michele

2012-01-01

A molecular dynamics-based protocol is proposed for finding and scoring protein-ligand binding poses. This protocol uses the recently developed reconnaissance metadynamics method, which employs a self-learning algorithm to construct a bias that pushes the system away from the kinetic traps where it would otherwise remain. The exploration of phase space with this algorithm is shown to be roughly six to eight times faster than unbiased molecular dynamics and is only limited by the time taken to diffuse about the surface of the protein. We apply this method to the well-studied trypsin–benzamidine system and show that we are able to refind all the poses obtained from a reference EADock blind docking calculation. These poses can be scored based on the length of time the system remains trapped in the pose. Alternatively, one can perform dimensionality reduction on the output trajectory and obtain a map of phase space that can be used in more expensive free-energy calculations. PMID:22440749

Mathematical Thinking and Creativity through Mathematical Problem Posing and Solving

Directory of Open Access Journals (Sweden)

María F. Ayllón

2016-04-01

Full Text Available This work shows the relationship between the development of mathematical thinking and creativity with mathematical problem posing and solving. Creativity and mathematics are disciplines that do not usually appear together. Both concepts constitute complex processes sharing elements, such as fluency (number of ideas, flexibility (range of ideas, novelty (unique idea and elaboration (idea development. These factors contribute, among others, to the fact that schoolchildren are competent in mathematics. The problem solving and posing are a very powerful evaluation tool that shows the mathematical reasoning and creative level of a person. Creativity is part of the mathematics education and is a necessary ingredient to perform mathematical assignments. This contribution presents some important research works about problem posing and solving related to the development of mathematical knowledge and creativity. To that end, it is based on various beliefs reflected in the literature with respect to notions of creativity, problem solving and posing.

A Grasp-Pose Generation Method Based on Gaussian Mixture Models

Directory of Open Access Journals (Sweden)

Wenjia Wu

2015-11-01

Full Text Available A Gaussian Mixture Model (GMM-based grasp-pose generation method is proposed in this paper. Through offline training, the GMM is set up and used to depict the distribution of the robot's reachable orientations. By dividing the robot's workspace into small 3D voxels and training the GMM for each voxel, a look-up table covering all the workspace is built with the x, y and z positions as the index and the GMM as the entry. Through the definition of Task Space Regions (TSR, an object's feasible grasp poses are expressed as a continuous region. With the GMM, grasp poses can be preferentially sampled from regions with high reachability probabilities in the online grasp-planning stage. The GMM can also be used as a preliminary judgement of a grasp pose's reachability. Experiments on both a simulated and a real robot show the superiority of our method over the existing method.

Reproduction Symposium: does grazing on biosolids-treated pasture pose a pathophysiological risk associated with increased exposure to endocrine disrupting compounds?

Science.gov (United States)

Evans, N P; Bellingham, M; Sharpe, R M; Cotinot, C; Rhind, S M; Kyle, C; Erhard, H; Hombach-Klonisch, S; Lind, P M; Fowler, P A

2014-08-01

Biosolids (processed human sewage sludge), which contain low individual concentrations of an array of contaminants including heavy metals and organic pollutants such as polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB), and polychlorinated dibenzodioxins/polychlorinated dibenzofurans known to cause physiological disturbances, are increasingly being used as an agricultural fertilizer. This could pose a health threat to both humans and domestic and wild animal species. This review summarizes results of a unique model, used to determine the effects of exposure to mixtures of environmentally relevant concentrations of pollutants, in sheep grazed on biosolids-treated pastures. Pasture treatment results in nonsignificant increases in environmental chemical (EC) concentrations in soil. Whereas EC concentrations were increased in some tissues of both ewes and their fetuses, concentrations were low and variable and deemed to pose little risk to consumer health. Investigation of the effects of gestational EC exposure on fetal development has highlighted a number of issues. The results indicate that gestational EC exposure can adversely affect gonadal development (males and females) and that these effects can impact testicular morphology, ovarian follicle numbers and health, and the transcriptome and proteome in adult animals. In addition, EC exposure can be associated with altered expression of GnRH, GnRH receptors, galanin receptors, and kisspeptin mRNA within the hypothalamus and pituitary gland, gonadotroph populations within the pituitary gland, and regional aberrations in thyroid morphology. In most cases, these anatomical and functional differences do not result in altered peripheral hormone concentrations or reproductive function (e.g., lambing rate), indicating physiological compensation under the conditions tested. Physiological compensation is also suggested from studies that indicate that EC effects may be greater when exposure occurs either

Investigation of Problem-Solving and Problem-Posing Abilities of Seventh-Grade Students

Science.gov (United States)

Arikan, Elif Esra; Ünal, Hasan

2015-01-01

This study aims to examine the effect of multiple problem-solving skills on the problem-posing abilities of gifted and non-gifted students and to assess whether the possession of such skills can predict giftedness or affect problem-posing abilities. Participants' metaphorical images of problem posing were also explored. Participants were 20 gifted…

Sustainable nanotechnology decision support system: bridging risk management, sustainable innovation and risk governance

NARCIS (Netherlands)

Subramanian, V.; Semenzin, E.; Hristozov, D.; Zabeo, A.; Malsch, I.; McAlea, E.; Murphy, F.; Mullins, M.; Harmelen, T. van; Ligthart, T.; Linkov, I.; Marcomini, A.

2016-01-01

The significant uncertainties associated with the (eco)toxicological risks of engineered nanomaterials pose challenges to the development of nano-enabled products toward greatest possible societal benefit. This paper argues for the use of risk governance approaches to manage nanotechnology risks and

Increased prevalence of cardiovascular disease and risk biomarkers in patients with unknown type 2 diabetes visiting cardiology specialists: results from the DIASPORA study.

Science.gov (United States)

Schöndorf, Thomas; Lübben, Georg; Karagiannis, Efstrathios; Erdmann, Erland; Forst, Thomas; Pfützner, Andreas

2010-04-01

Patients with diabetes mellitus and IGT have a high risk for cardiovascular events. It is tempting to speculate that these patients are often first seen by cardiologists. This cross-sectional study investigates the diabetes prevalence in cardiology care units and the correlated metabolic conditions as assessed by several circulating biomarkers. Patients aged 55 or older with suspected or overt coronary heart disease were eligible for trial participation. Fasting blood samples were drawn from patients to determine HOMA score, glycaemic and lipid profile, and several risk biomarkers. An OGTT was performed in patients without known diabetes. We enrolled 530 patients (181 male, 349 female, mean age, 68+/-7 years) in this study from 22 German cardiology centres; 156 patients (29.4%) had known diabetes and OGTT revealed that 184 patients (34.7%) had no diabetes, 106 patients (20.0%) had IGT or IFG and 84 patients (15.9%) were newly diagnosed with diabetes. Increased cardiovascular risk as reflected by increased hsCRP, ICAM and MMP-9 values was observed in diabetes patients. A higher cardiovascular biomarkers risk profile was seen in the IGT/IFG cohort. This study confirms the observation that one third of patients of a cardiologic care unit suffer from impaired glucose regulation. Furthermore, the cardiology patients with previously unknown glucose homeostasis abnormalities had a higher prevalence of macrovacular disease and an impaired biomarker risk profile. This study underlines the importance of joint treatment efforts by cardiologists in concert with diabetologists for treatment of this patient group at high risk for cardiovascular events.

Preparatory power posing affects nonverbal presence and job interview performance.

Science.gov (United States)

Cuddy, Amy J C; Wilmuth, Caroline A; Yap, Andy J; Carney, Dana R

2015-07-01

The authors tested whether engaging in expansive (vs. contractive) "power poses" before a stressful job interview--preparatory power posing--would enhance performance during the interview. Participants adopted high-power (i.e., expansive, open) poses or low-power (i.e., contractive, closed) poses, and then prepared and delivered a speech to 2 evaluators as part of a mock job interview. All interview speeches were videotaped and coded for overall performance and hireability and for 2 potential mediators: verbal content (e.g., structure, content) and nonverbal presence (e.g., captivating, enthusiastic). As predicted, those who prepared for the job interview with high- (vs. low-) power poses performed better and were more likely to be chosen for hire; this relation was mediated by nonverbal presence, but not by verbal content. Although previous research has focused on how a nonverbal behavior that is enacted during interactions and observed by perceivers affects how those perceivers evaluate and respond to the actor, this experiment focused on how a nonverbal behavior that is enacted before the interaction and unobserved by perceivers affects the actor's performance, which, in turn, affects how perceivers evaluate and respond to the actor. This experiment reveals a theoretically novel and practically informative result that demonstrates the causal relation between preparatory nonverbal behavior and subsequent performance and outcomes. (c) 2015 APA, all rights reserved).

Consistently Showing Your Best Side? Intra-individual Consistency in #Selfie Pose Orientation

Science.gov (United States)

Lindell, Annukka K.

2017-01-01

Painted and photographic portraits of others show an asymmetric bias: people favor their left cheek. Both experimental and database studies confirm that the left cheek bias extends to selfies. To date all such selfie studies have been cross-sectional; whether individual selfie-takers tend to consistently favor the same pose orientation, or switch between multiple poses, remains to be determined. The present study thus examined intra-individual consistency in selfie pose orientations. Two hundred selfie-taking participants (100 male and 100 female) were identified by searching #selfie on Instagram. The most recent 10 single-subject selfies for the each of the participants were selected and coded for type of selfie (normal; mirror) and pose orientation (left, midline, right), resulting in a sample of 2000 selfies. Results indicated that selfie-takers do tend to consistently adopt a preferred pose orientation (α = 0.72), with more participants showing an overall left cheek bias (41%) than would be expected by chance (overall right cheek bias = 31.5%; overall midline bias = 19.5%; no overall bias = 8%). Logistic regression modellng, controlling for the repeated measure of participant identity, indicated that sex did not affect pose orientation. However, selfie type proved a significant predictor when comparing left and right cheek poses, with a stronger left cheek bias for mirror than normal selfies. Overall, these novel findings indicate that selfie-takers show intra-individual consistency in pose orientation, and in addition, replicate the previously reported left cheek bias for selfies and other types of portrait, confirming that the left cheek bias also presents within individuals’ selfie corpora. PMID:28270790

Contaminated site risk and uncertainty assessment for impacts on surface and groundwater

DEFF Research Database (Denmark)

Thomsen, Nanna Isbak

available between sites and choosing between the need for further investigation or remediation. This is a question of prioritizing the sites that pose the greatest risk, and it is a matter of making decisions under uncertainty. Both tasks require a structured assessment of the risk posed by the contaminated...... sites. In a conventional risk assessment of a contaminated site, risk is evaluated by assessing whether a concentration guideline is exceeded at a specific point of compliance in the water resource of interest. If the guideline is exceeded, it is concluded that the site poses a risk. However......, a contaminated site may pose a threat to multiple water resources, or multiple contaminated sites may threaten a single water resource. For more advanced risk assessments, it is therefore relevant to develop methods that can handle this challenge. In this thesis, four contributions are made to the field...

Cultural adaptations to the differential threats posed by hot versus cold climates.

Science.gov (United States)

Murray, Damian R

2013-10-01

Hot and cold climates have posed differential threats to human survival throughout history. Cold temperatures can pose direct threats to survival in themselves, whereas hot temperatures may pose threats indirectly through higher prevalence of infectious disease. These differential threats yield convergent predictions for the relationship between more demanding climates and freedom of expression, but divergent predictions for freedom from discrimination.

The relative pose estimation of aircraft based on contour model

Science.gov (United States)

Fu, Tai; Sun, Xiangyi

2017-02-01

This paper proposes a relative pose estimation approach based on object contour model. The first step is to obtain a two-dimensional (2D) projection of three-dimensional (3D)-model-based target, which will be divided into 40 forms by clustering and LDA analysis. Then we proceed by extracting the target contour in each image and computing their Pseudo-Zernike Moments (PZM), thus a model library is constructed in an offline mode. Next, we spot a projection contour that resembles the target silhouette most in the present image from the model library with reference of PZM; then similarity transformation parameters are generated as the shape context is applied to match the silhouette sampling location, from which the identification parameters of target can be further derived. Identification parameters are converted to relative pose parameters, in the premise that these values are the initial result calculated via iterative refinement algorithm, as the relative pose parameter is in the neighborhood of actual ones. At last, Distance Image Iterative Least Squares (DI-ILS) is employed to acquire the ultimate relative pose parameters.

Problem Posing with Realistic Mathematics Education Approach in Geometry Learning

Science.gov (United States)

Mahendra, R.; Slamet, I.; Budiyono

2017-09-01

One of the difficulties of students in the learning of geometry is on the subject of plane that requires students to understand the abstract matter. The aim of this research is to determine the effect of Problem Posing learning model with Realistic Mathematics Education Approach in geometry learning. This quasi experimental research was conducted in one of the junior high schools in Karanganyar, Indonesia. The sample was taken using stratified cluster random sampling technique. The results of this research indicate that the model of Problem Posing learning with Realistic Mathematics Education Approach can improve students’ conceptual understanding significantly in geometry learning especially on plane topics. It is because students on the application of Problem Posing with Realistic Mathematics Education Approach are become to be active in constructing their knowledge, proposing, and problem solving in realistic, so it easier for students to understand concepts and solve the problems. Therefore, the model of Problem Posing learning with Realistic Mathematics Education Approach is appropriately applied in mathematics learning especially on geometry material. Furthermore, the impact can improve student achievement.

Cybersecurity Risks: Are They Inflated?

OpenAIRE

Petr Chrapavy

2016-01-01

With various views being posed on cybersecurity, this paper examines the proposition that cybersecurity risks are inflated. Due to the complexity of the cybersecurity environment, the risks will be dichotomised into two distinct categories—those posed by cybercrime, and those classified as cyber-warfare. In relation to cyber-crime, the paper examines the rise of cyber-crime, its costs, and the views of these factors by “alarmists” and “sceptics.” In relation to cyber-war, the paper sets aside...

Pose and Solve Varignon Converse Problems

Science.gov (United States)

Contreras, José N.

2014-01-01

The activity of posing and solving problems can enrich learners' mathematical experiences because it fosters a spirit of inquisitiveness, cultivates their mathematical curiosity, and deepens their views of what it means to do mathematics. To achieve these goals, a mathematical problem needs to be at the appropriate level of difficulty,…

Development and evolution of risk assessment for food allergens

DEFF Research Database (Denmark)

Crevel, Rene' W. R.; Baumert, Joseph L.; Baka, Athanasia

2014-01-01

The need to assess the risk from food allergens derives directly from the need to manage effectively this food safety hazard. Work spanning the last two decades dispelled the initial thinking that food allergens were so unique that the risk they posed was not amenable to established risk assessme...... provided valuable insights, leading to further refinements and generating testable hypotheses. Their application to estimate the risk posed by the concurrent consumption of two potentially contaminated foods illustrates their power....

Head Pose Estimation on Eyeglasses Using Line Detection and Classification Approach

Science.gov (United States)

Setthawong, Pisal; Vannija, Vajirasak

This paper proposes a unique approach for head pose estimation of subjects with eyeglasses by using a combination of line detection and classification approaches. Head pose estimation is considered as an important non-verbal form of communication and could also be used in the area of Human-Computer Interface. A major improvement of the proposed approach is that it allows estimation of head poses at a high yaw/pitch angle when compared with existing geometric approaches, does not require expensive data preparation and training, and is generally fast when compared with other approaches.

Attribute And-Or Grammar for Joint Parsing of Human Pose, Parts and Attributes.

Science.gov (United States)

Park, Seyoung; Nie, Xiaohan; Zhu, Song-Chun

2017-07-25

This paper presents an attribute and-or grammar (A-AOG) model for jointly inferring human body pose and human attributes in a parse graph with attributes augmented to nodes in the hierarchical representation. In contrast to other popular methods in the current literature that train separate classifiers for poses and individual attributes, our method explicitly represents the decomposition and articulation of body parts, and account for the correlations between poses and attributes. The A-AOG model is an amalgamation of three traditional grammar formulations: (i)Phrase structure grammar representing the hierarchical decomposition of the human body from whole to parts; (ii)Dependency grammar modeling the geometric articulation by a kinematic graph of the body pose; and (iii)Attribute grammar accounting for the compatibility relations between different parts in the hierarchy so that their appearances follow a consistent style. The parse graph outputs human detection, pose estimation, and attribute prediction simultaneously, which are intuitive and interpretable. We conduct experiments on two tasks on two datasets, and experimental results demonstrate the advantage of joint modeling in comparison with computing poses and attributes independently. Furthermore, our model obtains better performance over existing methods for both pose estimation and attribute prediction tasks.

Quantum circuits cannot control unknown operations

International Nuclear Information System (INIS)

Araújo, Mateus; Feix, Adrien; Costa, Fabio; Brukner, Časlav

2014-01-01

One of the essential building blocks of classical computer programs is the ‘if’ clause, which executes a subroutine depending on the value of a control variable. Similarly, several quantum algorithms rely on applying a unitary operation conditioned on the state of a control system. Here we show that this control cannot be performed by a quantum circuit if the unitary is completely unknown. The task remains impossible even if we allow the control to be done modulo a global phase. However, this no-go theorem does not prevent implementing quantum control of unknown unitaries in practice, as any physical implementation of an unknown unitary provides additional information that makes the control possible. We then argue that one should extend the quantum circuit formalism to capture this possibility in a straightforward way. This is done by allowing unknown unitaries to be applied to subspaces and not only to subsystems. (paper)

Categorization of questions posed before and after inquiry-based learning

Directory of Open Access Journals (Sweden)

Sandra Milena García González

2014-07-01

Full Text Available Posing research questions is the central ability of the scientific thought. This article examines the ability of sixth grade children to pose researchable questions before and after a three months’ work on a didactic sequence based on the inquiry school model. According to their purpose, the questions asked by children, after reading a text, were classified into researchable questions -susceptible to be empirically explored-, questions about a cause, and questions on a piece of data. The results show that the amount and the type of questions the students were able to pose during the intervention changed, from most of questions on data or information, to most of researchable questions, subsequently, the importance of designing teaching approaches to foster this ability was proved.

Automatic generation of statistical pose and shape models for articulated joints.

Science.gov (United States)

Xin Chen; Graham, Jim; Hutchinson, Charles; Muir, Lindsay

2014-02-01

Statistical analysis of motion patterns of body joints is potentially useful for detecting and quantifying pathologies. However, building a statistical motion model across different subjects remains a challenging task, especially for a complex joint like the wrist. We present a novel framework for simultaneous registration and segmentation of multiple 3-D (CT or MR) volumes of different subjects at various articulated positions. The framework starts with a pose model generated from 3-D volumes captured at different articulated positions of a single subject (template). This initial pose model is used to register the template volume to image volumes from new subjects. During this process, the Grow-Cut algorithm is used in an iterative refinement of the segmentation of the bone along with the pose parameters. As each new subject is registered and segmented, the pose model is updated, improving the accuracy of successive registrations. We applied the algorithm to CT images of the wrist from 25 subjects, each at five different wrist positions and demonstrated that it performed robustly and accurately. More importantly, the resulting segmentations allowed a statistical pose model of the carpal bones to be generated automatically without interaction. The evaluation results show that our proposed framework achieved accurate registration with an average mean target registration error of 0.34 ±0.27 mm. The automatic segmentation results also show high consistency with the ground truth obtained semi-automatically. Furthermore, we demonstrated the capability of the resulting statistical pose and shape models by using them to generate a measurement tool for scaphoid-lunate dissociation diagnosis, which achieved 90% sensitivity and specificity.

Would Aluminum and Nickel Content of Apricot Pose Health Risk to Human?

Directory of Open Access Journals (Sweden)

Gholamhossein DAVARYNEJAD

2012-05-01

Full Text Available Higher demands of food production for human consumption increased uses of fertilizers and other chemicals that arise in a major public problem and heavy-metal pollution. Levels of Aluminum and Nickel which affect mankind health in exact doses, were determined in fresh and dried samples of �Jumbo Cot�, �Tom Cot�, �Gold Strike�, �Gold Bar�, Bergeron�, �Bergarouge�, �Sweet Cot�, �Yellow cot� and �Zebra� apricot cultivars to assess possible health risk of apricot (Prunus armeniaca L. consumption. Highest content of Al and Ni among all cultivars, where 9.71 and 2.14 mg/kg of dehydrated apricot samples. Fresh fruit samples maximally contain 2.9 and 0.425 mg/kg of Aluminum and Nickel respectively. Data analysis showed significant differences between cultivars for Al and Ni. Furthermore, to reveal the health-risk possibility of dried and fresh fruit consumption daily intake of elements and health-risk index were calculated and compared.

Would Aluminum and Nickel Content of Apricot Pose Health Risk to Human?

Directory of Open Access Journals (Sweden)

Gholamhossein DAVARYNEJAD

2012-05-01

Full Text Available Higher demands of food production for human consumption increased uses of fertilizers and other chemicals that arise in a major public problem and heavy-metal pollution. Levels of Aluminum and Nickel which affect mankind health in exact doses, were determined in fresh and dried samples of Jumbo Cot, Tom Cot, Gold Strike, Gold Bar, Bergeron, Bergarouge, Sweet Cot, Yellow cot and Zebra apricot cultivars to assess possible health risk of apricot (Prunus armeniaca L. consumption. Highest content of Al and Ni among all cultivars, where 9.71 and 2.14 mg/kg of dehydrated apricot samples. Fresh fruit samples maximally contain 2.9 and 0.425 mg/kg of Aluminum and Nickel respectively. Data analysis showed significant differences between cultivars for Al and Ni. Furthermore, to reveal the health-risk possibility of dried and fresh fruit consumption daily intake of elements and health-risk index were calculated and compared.

Single leg balancing in ballet: effects of shoe conditions and poses.

Science.gov (United States)

Lobo da Costa, Paula H; Azevedo Nora, Fernanda G S; Vieira, Marcus Fraga; Bosch, Kerstin; Rosenbaum, Dieter

2013-03-01

The purpose of this study was to describe the effects of lower limb positioning and shoe conditions on stability levels of selected single leg ballet poses performed in demi-pointe position. Fourteen female non-professional ballet dancers (mean age of 18.4±2.8 years and mean body mass index of 21.5±2.8kg/m(2)) who had practiced ballet for at least seven years, without any musculoskeletal impairment volunteered to participate in this study. A capacitive pressure platform allowed for the assessment of center of pressure variables related to the execution of three single leg ballet poses in demi pointé position: attitude devant, attitude derriére, and attitude a la second. Peak pressures, contact areas, COP oscillation areas, anterior-posterior and medio-lateral COP oscillations and velocities were compared between two shoe conditions (barefoot versus slippers) and among the different poses. Barefoot performances produced more stable poses with significantly higher plantar contact areas, smaller COP oscillation areas and smaller anterior-posterior COP oscillations. COP oscillation areas, anterior-posterior COP oscillations and medio-lateral COP velocities indicated that attitude a la second is the least challenging and attitude derriére the most challenging pose. Copyright © 2012 Elsevier B.V. All rights reserved.

Risk to tourists posed by wild mammals in South Africa.

Science.gov (United States)

Durrheim, D N; Leggat, P A

1999-09-01

One of South Africa's principal tourist attractions is the opportunity to encounter Africa's large mammals in the wild. Attacks by these mammals can be exceptionally newsworthy with potentially deleterious effects on tourism. Little is known about the risk of injury and death caused by wild mammals to visitors to South Africa's nature reserves. The aim of this study was to determine the incidence of fatal and nonfatal attacks on tourists by wild mammals in South Africa and to ascertain avoidable factors, if any. Commercial press records covering all South African Newspapers archived at the Independent Newspapers' central library were systematically reviewed for a 10-year period, January 1988 to December 1997 inclusive, to identify all deaths and injuries to domestic and international tourists resulting from encounters with wild mammals in South Africa. All of these incidents were analyzed to ascertain avoidable factors. During the review period seven tourists, including two students from Thailand and a German traveler, were killed by wild mammals in South Africa. Three of the four deaths ascribed to lions resulted from tourists carelessly approaching prides on foot in lion reserves. A judicial inquiry found that the management of a KwaZulu-Natal Reserve was culpable for the remaining death. Tourist ignorance of animal behavior and flagrant disregard of rules contributed to the two fatalities involving hippopotami. The unusual behavior manifested by the bull elephant responsible for the final death, resulted from discomfort caused by a dental problem to this pachyderm. During the same period there were 14 nonfatal attacks on tourists, including five by hippo, three by buffalo, two by rhino, and one each by a lion, leopard, zebra and musth elephant. Only the latter occurred while the visitor was in a motor vehicle. Tourist ethological naivete and failure to determine the experience of trail guides prior to travel, resulted in inadvertent agonistic behavior

Application of Shape Similarity in Pose Selection and Virtual Screening in CSARdock2014 Exercise.

Science.gov (United States)

Kumar, Ashutosh; Zhang, Kam Y J

2016-06-27

To evaluate the applicability of shape similarity in docking-based pose selection and virtual screening, we participated in the CSARdock2014 benchmark exercise for identifying the correct docking pose of inhibitors targeting factor XA, spleen tyrosine kinase, and tRNA methyltransferase. This exercise provides a valuable opportunity for researchers to test their docking programs, methods, and protocols in a blind testing environment. In the CSARdock2014 benchmark exercise, we have implemented an approach that uses ligand 3D shape similarity to facilitate docking-based pose selection and virtual screening. We showed here that ligand 3D shape similarity between bound poses could be used to identify the native-like pose from an ensemble of docking-generated poses. Our method correctly identified the native pose as the top-ranking pose for 73% of test cases in a blind testing environment. Moreover, the pose selection results also revealed an excellent correlation between ligand 3D shape similarity scores and RMSD to X-ray crystal structure ligand. In the virtual screening exercise, the average RMSD for our pose prediction was found to be 1.02 Å, and it was one of the top performances achieved in CSARdock2014 benchmark exercise. Furthermore, the inclusion of shape similarity improved virtual screening performance of docking-based scoring and ranking. The coefficient of determination (r(2)) between experimental activities and docking scores for 276 spleen tyrosine kinase inhibitors was found to be 0.365 but reached 0.614 when the ligand 3D shape similarity was included.

An Improved Method of Pose Estimation for Lighthouse Base Station Extension.

Science.gov (United States)

Yang, Yi; Weng, Dongdong; Li, Dong; Xun, Hang

2017-10-22

In 2015, HTC and Valve launched a virtual reality headset empowered with Lighthouse, the cutting-edge space positioning technology. Although Lighthouse is superior in terms of accuracy, latency and refresh rate, its algorithms do not support base station expansion, and is flawed concerning occlusion in moving targets, that is, it is unable to calculate their poses with a small set of sensors, resulting in the loss of optical tracking data. In view of these problems, this paper proposes an improved pose estimation algorithm for cases where occlusion is involved. Our algorithm calculates the pose of a given object with a unified dataset comprising of inputs from sensors recognized by all base stations, as long as three or more sensors detect a signal in total, no matter from which base station. To verify our algorithm, HTC official base stations and autonomous developed receivers are used for prototyping. The experiment result shows that our pose calculation algorithm can achieve precise positioning when a few sensors detect the signal.

Bisphenol A and risk management ethics.

Science.gov (United States)

Resnik, David B; Elliott, Kevin C

2015-03-01

It is widely recognized that endocrine disrupting compounds, such as Bisphenol A, pose challenges for traditional paradigms in toxicology, insofar as these substances appear to have a wider range of low-dose effects than previously recognized. These compounds also pose challenges for ethics and policymaking. When a chemical does not have significant low-dose effects, regulators can allow it to be introduced into commerce or the environment, provided that procedures and rules are in place to keep exposures below an acceptable level. This option allows society to maximize the benefits from the use of the chemical while minimizing risks to human health or the environment, and it represents a compromise between competing values. When it is not possible to establish acceptable exposure levels for chemicals that pose significant health or environmental risks, the most reasonable options for risk management may be to enact either partial or complete bans on their use. These options create greater moral conflict than other risk management strategies, leaving policymakers difficult choices between competing values. © 2014 John Wiley & Sons Ltd.

Performing the lockout/tagout risk assessment.

Science.gov (United States)

Wallace, W Jon

2007-03-01

Lockout/tagout provides the greatest level routine, repetitive, and integral to the production process, a risk assessment should be performed. If the task performed poses an unacceptable risk, acceptable risk reduction methods should be implemented to reduce the risk to acceptable levels.

Enhancing students’ mathematical problem posing skill through writing in performance tasks strategy

Science.gov (United States)

Kadir; Adelina, R.; Fatma, M.

2018-01-01

Many researchers have studied the Writing in Performance Task (WiPT) strategy in learning, but only a few paid attention on its relation to the problem-posing skill in mathematics. The problem-posing skill in mathematics covers problem reformulation, reconstruction, and imitation. The purpose of the present study was to examine the effect of WiPT strategy on students’ mathematical problem-posing skill. The research was conducted at a Public Junior Secondary School in Tangerang Selatan. It used a quasi-experimental method with randomized control group post-test. The samples were 64 students consists of 32 students of the experiment group and 32 students of the control. A cluster random sampling technique was used for sampling. The research data were obtained by testing. The research shows that the problem-posing skill of students taught by WiPT strategy is higher than students taught by a conventional strategy. The research concludes that the WiPT strategy is more effective in enhancing the students’ mathematical problem-posing skill compared to the conventional strategy.

Oil sands tailings preliminary ecological risk assessment

International Nuclear Information System (INIS)

1994-01-01

Chemical data collected from various oil sands soil-tailings mixtures were used to determine the ecological risk that such tailings would pose to terrestrial wildlife at the surface of a reclaimed site. A methodology that could be used to evaluate the risks posed by various reclamation options (for dry land only) was proposed. Risks associated with other reclamation options, such as wet landscapes or deeper in-pit disposal, were not evaluated. Ten constituents (eight organic and two inorganic) were found to pose a threat to terrestrial biota. The relative contribution of different exposure pathways (water and food ingestion, incidental soil ingestion, inhalation) were studied by probabilistic models. Some physical and chemical reclamation alternatives which involve incorporating oil sands tailings in the landscape to produce a surface that could sustain a productive ecosystem, were described. 53 refs., 15 tabs., 3 figs

Teach it Yourself - Fast Modeling of Industrial Objects for 6D Pose Estimation

DEFF Research Database (Denmark)

Sølund, Thomas; Rajeeth Savarimuthu, Thiusius; Glent Buch, Anders

2015-01-01

In this paper, we present a vision system that allows a human to create new 3D models of novel industrial parts by placing the part in two different positions in the scene. The two shot modeling framework generates models with a precision that allows the model to be used for 6D pose estimation wi....... In addition, the models are applied in a pose estimation application, evaluated with 37 different scenes with 61 unique object poses. The pose estimation results show a mean translation error on 4.97 mm and a mean rotation error on 3.38 degrees....

Managing the risks of risk management on large fires

Science.gov (United States)

Donald G. MacGregor; Armando González-Cabán

2013-01-01

Large fires pose risks to a number of important values, including the ecology, property and the lives of incident responders. A relatively unstudied aspect of fire management is the risks to which incident managers are exposed due to organizational and sociopolitical factors that put them in a position of, for example, potential liability or degradation of their image...

ONKALO POSE experiment. Phase 3: execution and monitoring

International Nuclear Information System (INIS)

Valli, J.; Hakala, M.; Wanne, T.; Kantia, P.; Siren, T.

2014-01-01

In-depth knowledge of the in situ stress state at the Olkiluoto site is critical for stability assessment both prior to and after deposition of spent nuclear fuel in order to understand and avoid potential damage to the rock at the site. Posiva's Olkiluoto Spalling Experiment (POSE) was designed specifically for this purpose with three primary goals: establish the in situ spalling/damage strength of Olkiluoto migmatitic gneiss, establish the state of in situ stress at the -345 m depth level and act as a Prediction-Outcome (P-O) exercise. Phases 1 and 2 of POSE are outlined in WR 2012-60. The objectives of the third phase of the POSE experiment are the same as the original objectives outlined above. This report outlines the execution and results of the third phase of the POSE experiment. The third phase of the experiment involved internally heating the third experimental hole (ONK-EH3) of the POSE niche in order to cause a symmetrical thermal stress increase around the hole due to the thermal expansion of rock. This thermomechanically induced stress increase, coupled with the estimated existing in situ stress state, should cause the maximum principal stress around the hole to exceed the predicted spalling strength of the rock around the hole. ONK-EH3 is located almost completely in pegmatitic granite. Four fractures near the top of the hole were mapped after boring ONK-EH3, and a tensile failure located at the contact between mica-rich gneiss and pegmatitic granite was observed 18 months after boring, prior to the experiment. Based on predictive calculations and the estimated in situ state of stress, the maximum principal stress magnitude should reach ca. 100 MPa when the temperature was just below 100 deg C after 12 weeks of heating. There were problems with the heater control unit at the beginning of the experiment, after which heating proceeded according to plan. The crack damage threshold of pegmatitic granite has been determined to be 85 ±17 MPa at Olkiluoto

Optical neural network system for pose determination of spinning satellites

Science.gov (United States)

Lee, Andrew; Casasent, David

1990-01-01

An optical neural network architecture and algorithm based on a Hopfield optimization network are presented for multitarget tracking. This tracker utilizes a neuron for every possible target track, and a quadratic energy function of neural activities which is minimized using gradient descent neural evolution. The neural net tracker is demonstrated as part of a system for determining position and orientation (pose) of spinning satellites with respect to a robotic spacecraft. The input to the system is time sequence video from a single camera. Novelty detection and filtering are utilized to locate and segment novel regions from the input images. The neural net multitarget tracker determines the correspondences (or tracks) of the novel regions as a function of time, and hence the paths of object (satellite) parts. The path traced out by a given part or region is approximately elliptical in image space, and the position, shape and orientation of the ellipse are functions of the satellite geometry and its pose. Having a geometric model of the satellite, and the elliptical path of a part in image space, the three-dimensional pose of the satellite is determined. Digital simulation results using this algorithm are presented for various satellite poses and lighting conditions.

Teachers Implementing Mathematical Problem Posing in the Classroom: Challenges and Strategies

Science.gov (United States)

Leung, Shuk-kwan S.

2013-01-01

This paper reports a study about how a teacher educator shared knowledge with teachers when they worked together to implement mathematical problem posing (MPP) in the classroom. It includes feasible methods for getting practitioners to use research-based tasks aligned to the curriculum in order to encourage children to pose mathematical problems.…

The New Transgenic cry1Ab/vip3H Rice Poses No Unexpected Ecological Risks to Arthropod Communities in Rice Agroecosystems.

Science.gov (United States)

Lu, Zengbin; Dang, Cong; Han, Naishun; Shen, Zhicheng; Peng, Yufa; Stanley, David; Ye, Gongyin

2016-04-01

The ecological risks to nontarget organisms should be rigorously assessed before Bt crops are released. Here, the impacts of a new Cry1Ab/Vip3H rice line on arthropod communities in rice agroecosystems were evaluated across 3 yr. Arthropods collected via vacuum were sorted into five guilds. The abundance and proportion of each guild as well as community-level parameters were determined in Cry1Ab/Vip3H and control rice fields. Changes in arthropod species assemblage over sampling dates were investigated by principal response curves (PRCs). Cry1Ab/Vip3H rice did not exert significant impacts on the seasonal density and proportion of each guild, except parasitoids. Detritivore seasonal density, but not its relative abundance, was significantly affected by Cry1Ab/Vip3H rice. Four community indices (species richness S, Shannon-Wiener index H', Simpson index D, and evenness index J') were similar between rice types. PRCs revealed a slight community difference between rice types in the past two tested years, with rice types accounting for 1.0-3.5% of the variance among arthropod communities. However, sampling dates explain 32.1-67.6% for these community differences. Of the 46 taxa with higher species weights, 26.1% of the taxa were significantly different, including seven taxa with higher abundance and five with lower density in Cry1Ab/Vip3H rice fields. These differences may be attributed to change in abundance of prey or hosts but not to direct effects of Bt proteins. We infer that this new Cry1Ab/Vip3H rice line poses no unintended ecological risks to the arthropod community. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

A multi-camera system for real-time pose estimation

Science.gov (United States)

Savakis, Andreas; Erhard, Matthew; Schimmel, James; Hnatow, Justin

2007-04-01

This paper presents a multi-camera system that performs face detection and pose estimation in real-time and may be used for intelligent computing within a visual sensor network for surveillance or human-computer interaction. The system consists of a Scene View Camera (SVC), which operates at a fixed zoom level, and an Object View Camera (OVC), which continuously adjusts its zoom level to match objects of interest. The SVC is set to survey the whole filed of view. Once a region has been identified by the SVC as a potential object of interest, e.g. a face, the OVC zooms in to locate specific features. In this system, face candidate regions are selected based on skin color and face detection is accomplished using a Support Vector Machine classifier. The locations of the eyes and mouth are detected inside the face region using neural network feature detectors. Pose estimation is performed based on a geometrical model, where the head is modeled as a spherical object that rotates upon the vertical axis. The triangle formed by the mouth and eyes defines a vertical plane that intersects the head sphere. By projecting the eyes-mouth triangle onto a two dimensional viewing plane, equations were obtained that describe the change in its angles as the yaw pose angle increases. These equations are then combined and used for efficient pose estimation. The system achieves real-time performance for live video input. Testing results assessing system performance are presented for both still images and video.

Information Security Risk Analysis

CERN Document Server

Peltier, Thomas R

2010-01-01

Offers readers with the knowledge and the skill-set needed to achieve a highly effective risk analysis assessment. This title demonstrates how to identify threats and then determine if those threats pose a real risk. It is suitable for industry and academia professionals.

A deep learning approach for pose estimation from volumetric OCT data.

Science.gov (United States)

Gessert, Nils; Schlüter, Matthias; Schlaefer, Alexander

2018-05-01

Tracking the pose of instruments is a central problem in image-guided surgery. For microscopic scenarios, optical coherence tomography (OCT) is increasingly used as an imaging modality. OCT is suitable for accurate pose estimation due to its micrometer range resolution and volumetric field of view. However, OCT image processing is challenging due to speckle noise and reflection artifacts in addition to the images' 3D nature. We address pose estimation from OCT volume data with a new deep learning-based tracking framework. For this purpose, we design a new 3D convolutional neural network (CNN) architecture to directly predict the 6D pose of a small marker geometry from OCT volumes. We use a hexapod robot to automatically acquire labeled data points which we use to train 3D CNN architectures for multi-output regression. We use this setup to provide an in-depth analysis on deep learning-based pose estimation from volumes. Specifically, we demonstrate that exploiting volume information for pose estimation yields higher accuracy than relying on 2D representations with depth information. Supporting this observation, we provide quantitative and qualitative results that 3D CNNs effectively exploit the depth structure of marker objects. Regarding the deep learning aspect, we present efficient design principles for 3D CNNs, making use of insights from the 2D deep learning community. In particular, we present Inception3D as a new architecture which performs best for our application. We show that our deep learning approach reaches errors at our ground-truth label's resolution. We achieve a mean average error of 14.89 ± 9.3 µm and 0.096 ± 0.072° for position and orientation learning, respectively. Copyright © 2018 Elsevier B.V. All rights reserved.

Chinese Unknown Word Recognition for PCFG-LA Parsing

Directory of Open Access Journals (Sweden)

Qiuping Huang

2014-01-01

Full Text Available This paper investigates the recognition of unknown words in Chinese parsing. Two methods are proposed to handle this problem. One is the modification of a character-based model. We model the emission probability of an unknown word using the first and last characters in the word. It aims to reduce the POS tag ambiguities of unknown words to improve the parsing performance. In addition, a novel method, using graph-based semisupervised learning (SSL, is proposed to improve the syntax parsing of unknown words. Its goal is to discover additional lexical knowledge from a large amount of unlabeled data to help the syntax parsing. The method is mainly to propagate lexical emission probabilities to unknown words by building the similarity graphs over the words of labeled and unlabeled data. The derived distributions are incorporated into the parsing process. The proposed methods are effective in dealing with the unknown words to improve the parsing. Empirical results for Penn Chinese Treebank and TCT Treebank revealed its effectiveness.

Recovering the 3d Pose and Shape of Vehicles from Stereo Images

Science.gov (United States)

Coenen, M.; Rottensteiner, F.; Heipke, C.

2018-05-01

The precise reconstruction and pose estimation of vehicles plays an important role, e.g. for autonomous driving. We tackle this problem on the basis of street level stereo images obtained from a moving vehicle. Starting from initial vehicle detections, we use a deformable vehicle shape prior learned from CAD vehicle data to fully reconstruct the vehicles in 3D and to recover their 3D pose and shape. To fit a deformable vehicle model to each detection by inferring the optimal parameters for pose and shape, we define an energy function leveraging reconstructed 3D data, image information, the vehicle model and derived scene knowledge. To minimise the energy function, we apply a robust model fitting procedure based on iterative Monte Carlo model particle sampling. We evaluate our approach using the object detection and orientation estimation benchmark of the KITTI dataset (Geiger et al., 2012). Our approach can deal with very coarse pose initialisations and we achieve encouraging results with up to 82 % correct pose estimations. Moreover, we are able to deliver very precise orientation estimation results with an average absolute error smaller than 4°.

Teaching Human Poses Interactively to a Social Robot

Science.gov (United States)

Gonzalez-Pacheco, Victor; Malfaz, Maria; Fernandez, Fernando; Salichs, Miguel A.

2013-01-01

The main activity of social robots is to interact with people. In order to do that, the robot must be able to understand what the user is saying or doing. Typically, this capability consists of pre-programmed behaviors or is acquired through controlled learning processes, which are executed before the social interaction begins. This paper presents a software architecture that enables a robot to learn poses in a similar way as people do. That is, hearing its teacher's explanations and acquiring new knowledge in real time. The architecture leans on two main components: an RGB-D (Red-, Green-, Blue- Depth) -based visual system, which gathers the user examples, and an Automatic Speech Recognition (ASR) system, which processes the speech describing those examples. The robot is able to naturally learn the poses the teacher is showing to it by maintaining a natural interaction with the teacher. We evaluate our system with 24 users who teach the robot a predetermined set of poses. The experimental results show that, with a few training examples, the system reaches high accuracy and robustness. This method shows how to combine data from the visual and auditory systems for the acquisition of new knowledge in a natural manner. Such a natural way of training enables robots to learn from users, even if they are not experts in robotics. PMID:24048336

Teaching Human Poses Interactively to a Social Robot

Directory of Open Access Journals (Sweden)

Miguel A. Salichs

2013-09-01

Full Text Available The main activity of social robots is to interact with people. In order to do that, the robot must be able to understand what the user is saying or doing. Typically, this capability consists of pre-programmed behaviors or is acquired through controlled learning processes, which are executed before the social interaction begins. This paper presents a software architecture that enables a robot to learn poses in a similar way as people do. That is, hearing its teacher’s explanations and acquiring new knowledge in real time. The architecture leans on two main components: an RGB-D (Red-, Green-, Blue- Depth -based visual system, which gathers the user examples, and an Automatic Speech Recognition (ASR system, which processes the speech describing those examples. The robot is able to naturally learn the poses the teacher is showing to it by maintaining a natural interaction with the teacher. We evaluate our system with 24 users who teach the robot a predetermined set of poses. The experimental results show that, with a few training examples, the system reaches high accuracy and robustness. This method shows how to combine data from the visual and auditory systems for the acquisition of new knowledge in a natural manner. Such a natural way of training enables robots to learn from users, even if they are not experts in robotics.

An Investigation of Eighth Grade Students' Problem Posing Skills (Turkey Sample)

Science.gov (United States)

Arikan, Elif Esra; Ünal, Hasan

2015-01-01

To pose a problem refers to the creative activity for mathematics education. The purpose of the study was to explore the eighth grade students' problem posing ability. Three learning domains such as requiring four operations, fractions and geometry were chosen for this reason. There were two classes which were coded as class A and class B. Class A…

Analyzing Pre-Service Primary Teachers' Fraction Knowledge Structures through Problem Posing

Science.gov (United States)

Kilic, Cigdem

2015-01-01

In this study it was aimed to determine pre-service primary teachers' knowledge structures of fraction through problem posing activities. A total of 90 pre-service primary teachers participated in this study. A problem posing test consisting of two questions was used and the participants were asked to generate as many as problems based on the…

Improving attitudes toward mathematics learning with problem posing in class VIII

Science.gov (United States)

Vionita, Alfha; Purboningsih, Dyah

2017-08-01

This research is classroom action research which is collaborated to improve student's behavior toward math and mathematics learning at class VIII by using problem posing approach. The subject of research is all of students grade VIIIA which consist of 32 students. This research has been held on two period, first period is about 3 times meeting, and second period is about 4 times meeting. The instrument of this research is implementation of learning observation's guidance by using problem posing approach. Cycle test has been used to measure cognitive competence, and questionnaire to measure the students' behavior in mathematics learning process. The result of research shows the students' behavior has been improving after using problem posing approach. It is showed by the behavior's criteria of students that has increasing result from the average in first period to high in second period. Furthermore, the percentage of test result is also improve from 68,75% in first period to 78,13% in second period. On the other hand, the implementation of learning observation by using problem posing approach has also improving and it is showed by the average percentage of teacher's achievement in first period is 89,2% and student's achievement 85,8%. These results get increase in second period for both teacher and students' achievement which are 94,4% and 91,11%. As a result, students' behavior toward math learning process in class VIII has been improving by using problem posing approach.

Public health risks associated with the CANDU nuclear fuel cycle

International Nuclear Information System (INIS)

Paskievici, W.; Zikovsky, L.

1983-06-01

This report analyzes in a preliminary way the risks to the public posed by the CANDU nuclear fuel cycle. Part 1 considers radiological risks, while part 2 (published as INFO-0141-2) evaluates non-radiological risks. The report concludes that, for radiological risks, maximum individual risks to members of the public are less than 10 -5 per year for postulated accidents, are less than 1 percent of regulatory limits for normal operation and that collective doses are small, less than 3 person-sieverts. It is also concluded that radiological risks are much smaller than the non-radiological risks posed by activities of the nuclear fuel cycle

The health risk levels of different age groups of residents living in the vicinity of municipal solid waste incinerator posed by PCDD/Fs in atmosphere and soil.

Science.gov (United States)

Li, Jiafu; Zhang, Ying; Sun, Tingting; Hao, Huawei; Wu, Hao; Wang, Lili; Chen, Yuxing; Xing, Limin; Niu, Zhiguang

2018-08-01

In our study, health risk levels of different age groups of residents living in the vicinity of a municipal solid waste incinerator (MSWI) posed by polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in atmosphere and soil were evaluated. The toxic equivalent concentrations of PCDD/Fs (TEQ) in surrounding atmosphere and soil of studied MSWI were 0.05-0.12 pg I-TEQ Nm -3 and 7.622-15.450 ng I-TEQ kg -1 , respectively. The PCDFs/PCDDs (F/D) values of PCDD/Fs in surrounding atmosphere of studied MSWI ranged from 0.40 to 5.90 with a mean of 1.80, suggesting that the PCDD/Fs mainly came from combustion sources and studied MSWI could be a key source of PCDD/Fs in surrounding atmosphere. The F/D ratios of PCDD/Fs in surrounding soil ranged from 0.18 to 1.81 with a mean of 0.90, suggesting combustion is not the mainly sources of PCDD/Fs in surrounding soil, and studied MSWI may have limited influence on PCDD/Fs in surrounding soil. O8CDD and 2,3,4,7,8-P5CDF could be the total PCDD/Fs and TEQ indicators in surrounding atmosphere of studied MSWI, respectively. The carcinogenic risk (CR) values of PCDD/Fs in surrounding atmosphere and soil for children, teens and adults were 1.24E-06, 9.06E-07 and 4.41E-06, respectively, suggesting that the potential cancer risk occurred but the risk was at acceptable levels for both children and adults (risk for teens was negligible (risk (non-CR) values of three age groups were lower than 1, indicating that no obvious non-carcinogenic effects occurred. Inhalation of air was the largest contributor of health risk (both CR and non-CR) for three age groups. In addition, a comparison of the health risk between PCDD/Fs and other emerging contaminants and traditional pollutants in soil and atmosphere was performed, which will help us have a good view of the health risk levels of PCDD/Fs in surrounding environment of MWSI. Copyright © 2018 Elsevier B.V. All rights reserved.

Web-based Visualisation of Head Pose and Facial Expressions Changes:

DEFF Research Database (Denmark)

Kalliatakis, Grigorios; Vidakis, Nikolaos; Triantafyllidis, Georgios

2016-01-01

Despite significant recent advances in the field of head pose estimation and facial expression recognition, raising the cognitive level when analysing human activity presents serious challenges to current concepts. Motivated by the need of generating comprehensible visual representations from...... and accurately estimate head pose changes in unconstrained environment. In order to complete the secondary process of recognising four universal dominant facial expressions (happiness, anger, sadness and surprise), emotion recognition via facial expressions (ERFE) was adopted. After that, a lightweight data...

Cloud computing approaches for prediction of ligand binding poses and pathways.

Science.gov (United States)

Lawrenz, Morgan; Shukla, Diwakar; Pande, Vijay S

2015-01-22

We describe an innovative protocol for ab initio prediction of ligand crystallographic binding poses and highly effective analysis of large datasets generated for protein-ligand dynamics. We include a procedure for setup and performance of distributed molecular dynamics simulations on cloud computing architectures, a model for efficient analysis of simulation data, and a metric for evaluation of model convergence. We give accurate binding pose predictions for five ligands ranging in affinity from 7 nM to > 200 μM for the immunophilin protein FKBP12, for expedited results in cases where experimental structures are difficult to produce. Our approach goes beyond single, low energy ligand poses to give quantitative kinetic information that can inform protein engineering and ligand design.

Yoga Poses Increase Subjective Energy and State Self-Esteem in Comparison to ‘Power Poses’

Directory of Open Access Journals (Sweden)

Agnieszka Golec de Zavala

2017-05-01

Full Text Available Research on beneficial consequences of yoga focuses on the effects of yogic breathing and meditation. Less is known about the psychological effects of performing yoga postures. The present study investigated the effects of yoga poses on subjective sense of energy and self-esteem. The effects of yoga postures were compared to the effects of ‘power poses,’ which arguably increase the sense of power and self-confidence due to their association with interpersonal dominance (Carney et al., 2010. The study tested the novel prediction that yoga poses, which are not associated with interpersonal dominance but increase bodily energy, would increase the subjective feeling of energy and therefore increase self-esteem compared to ‘high power’ and ‘low power’ poses. A two factorial, between participants design was employed. Participants performed either two standing yoga poses with open front of the body (n = 19, two standing yoga poses with covered front of the body (n = 22, two expansive, high power poses (n = 21, or two constrictive, low power poses (n = 20 for 1-min each. The results showed that yoga poses in comparison to ‘power poses’ increased self-esteem. This effect was mediated by an increased subjective sense of energy and was observed when baseline trait self-esteem was controlled for. These results suggest that the effects of performing open, expansive body postures may be driven by processes other than the poses’ association with interpersonal power and dominance. This study demonstrates that positive effects of yoga practice can occur after performing yoga poses for only 2 min.

Monocular-Based 6-Degree of Freedom Pose Estimation Technology for Robotic Intelligent Grasping Systems

Directory of Open Access Journals (Sweden)

Tao Liu

2017-02-01

Full Text Available Industrial robots are expected to undertake ever more advanced tasks in the modern manufacturing industry, such as intelligent grasping, in which robots should be capable of recognizing the position and orientation of a part before grasping it. In this paper, a monocular-based 6-degree of freedom (DOF pose estimation technology to enable robots to grasp large-size parts at informal poses is proposed. A camera was mounted on the robot end-flange and oriented to measure several featured points on the part before the robot moved to grasp it. In order to estimate the part pose, a nonlinear optimization model based on the camera object space collinearity error in different poses is established, and the initial iteration value is estimated with the differential transformation. Measuring poses of the camera are optimized based on uncertainty analysis. Also, the principle of the robotic intelligent grasping system was developed, with which the robot could adjust its pose to grasp the part. In experimental tests, the part poses estimated with the method described in this paper were compared with those produced by a laser tracker, and results show the RMS angle and position error are about 0.0228° and 0.4603 mm. Robotic intelligent grasping tests were also successfully performed in the experiments.

A pose estimation method for unmanned ground vehicles in GPS denied environments

Science.gov (United States)

Tamjidi, Amirhossein; Ye, Cang

2012-06-01

This paper presents a pose estimation method based on the 1-Point RANSAC EKF (Extended Kalman Filter) framework. The method fuses the depth data from a LIDAR and the visual data from a monocular camera to estimate the pose of a Unmanned Ground Vehicle (UGV) in a GPS denied environment. Its estimation framework continuy updates the vehicle's 6D pose state and temporary estimates of the extracted visual features' 3D positions. In contrast to the conventional EKF-SLAM (Simultaneous Localization And Mapping) frameworks, the proposed method discards feature estimates from the extended state vector once they are no longer observed for several steps. As a result, the extended state vector always maintains a reasonable size that is suitable for online calculation. The fusion of laser and visual data is performed both in the feature initialization part of the EKF-SLAM process and in the motion prediction stage. A RANSAC pose calculation procedure is devised to produce pose estimate for the motion model. The proposed method has been successfully tested on the Ford campus's LIDAR-Vision dataset. The results are compared with the ground truth data of the dataset and the estimation error is ~1.9% of the path length.

Known Unknowns in Judgment and Choice

OpenAIRE

Walters, Daniel

2017-01-01

This dissertation investigates how people make inferences about missing information. Whereas most prior literature focuses on how people process known information, I show that the extent to which people make inferences about missing information impacts judgments and choices. Specifically, I investigate how (1) awareness of known unknowns affects overconfidence in judgment in Chapter 1, (2) beliefs about the knowability of unknowns impacts investment strategies in Chapter 2, and (3) inferences...

Perfusion-CT guided intravenous thrombolysis in patients with unknown-onset stroke: a randomized, double-blind, placebo-controlled, pilot feasibility trial.

Science.gov (United States)

Michel, Patrik; Ntaios, George; Reichhart, Marc; Schindler, Christian; Bogousslavsky, Julien; Maeder, Philip; Meuli, Reto; Wintermark, Max

2012-06-01

Patients with unknown stroke onset are generally excluded from acute recanalisation treatments. We designed a pilot study to assess feasibility of a trial of perfusion computed tomography (PCT)-guided thrombolysis in patients with ischemic tissue at risk of infarction and unknown stroke onset. Patients with a supratentorial stroke of unknown onset in the middle cerebral artery territory and significant volume of at-risk tissue on PCT were randomized to intravenous thrombolysis with alteplase (0.9 mg/kg) or placebo. Feasibility endpoints were randomization and blinded treatment of patients within 2 h after hospital arrival, and the correct application (estimation) of the perfusion imaging criteria. At baseline, there was a trend towards older age [69.5 (57-78) vs. 49 (44-78) years] in the thrombolysis group (n = 6) compared to placebo (n = 6). Regarding feasibility, hospital arrival to treatment delay was above the allowed 2 h in three patients (25%). There were two protocol violations (17%) regarding PCT, both underestimating the predicted infarct in patients randomized in the placebo group. No symptomatic hemorrhage or death occurred during the first 7 days. Three of the four (75%) and one of the five (20%) patients were recanalized in the thrombolysis and placebo group respectively. The volume of non-infarcted at-risk tissue was 84 (44-206) cm(3) in the treatment arm and 29 (8-105) cm(3) in the placebo arm. This pilot study shows that a randomized PCT-guided thrombolysis trial in patients with stroke of unknown onset may be feasible if issues such as treatment delays and reliable identification of tissue at risk of infarction tissue are resolved. Safety and efficiency of such an approach need to be established.

Perfusion-CT guided intravenous thrombolysis in patients with unknown-onset stroke: a randomized, double-blind, placebo-controlled, pilot feasibility trial

International Nuclear Information System (INIS)

Michel, Patrik; Ntaios, George; Reichhart, Marc; Schindler, Christian; Bogousslavsky, Julien; Maeder, Philip; Meuli, Reto; Wintermark, Max

2012-01-01

Patients with unknown stroke onset are generally excluded from acute recanalisation treatments. We designed a pilot study to assess feasibility of a trial of perfusion computed tomography (PCT)-guided thrombolysis in patients with ischemic tissue at risk of infarction and unknown stroke onset. Patients with a supratentorial stroke of unknown onset in the middle cerebral artery territory and significant volume of at-risk tissue on PCT were randomized to intravenous thrombolysis with alteplase (0.9 mg/kg) or placebo. Feasibility endpoints were randomization and blinded treatment of patients within 2 h after hospital arrival, and the correct application (estimation) of the perfusion imaging criteria. At baseline, there was a trend towards older age [69.5 (57-78) vs. 49 (44-78) years] in the thrombolysis group (n = 6) compared to placebo (n = 6). Regarding feasibility, hospital arrival to treatment delay was above the allowed 2 h in three patients (25%). There were two protocol violations (17%) regarding PCT, both underestimating the predicted infarct in patients randomized in the placebo group. No symptomatic hemorrhage or death occurred during the first 7 days. Three of the four (75%) and one of the five (20%) patients were recanalized in the thrombolysis and placebo group respectively. The volume of non-infarcted at-risk tissue was 84 (44-206) cm 3 in the treatment arm and 29 (8-105) cm 3 in the placebo arm. This pilot study shows that a randomized PCT-guided thrombolysis trial in patients with stroke of unknown onset may be feasible if issues such as treatment delays and reliable identification of tissue at risk of infarction tissue are resolved. Safety and efficiency of such an approach need to be established. (orig.)

Unintentional drinking-water contamination events of unknown origin: surrogate for terrorism preparedness.

Science.gov (United States)

Winston, Gary; Leventhal, Alex

2008-01-01

Drinking-water is a direct conduit to many human receptors. An intentional attack (e.g. terrorism) on drinking-water systems can shock and disrupt elements of national infrastructures. We report on an unintentional drinking-water contamination event that occurred in Tel Aviv, Israel in July, 2001. Initially of unknown origin, this event involved risk management strategies used by the Ministry of Health for abating a potential public health crisis as might be envisaged of water contamination due to terrorism. In an abrupt event of unknown origin, public health officials need to be responsible for the same level of preparedness and risk communication. This is emphasized by comparison of management strategies between the Tel Aviv event and one of dire consequences that occurred in Camelford, England in 1988. From the onset of the Tel Aviv incident, the public health strategy was to employ the precautionary principle by warning residents of the affected region to not drink tap water, even if boiled. This strategy was in contrast to an earlier crisis that occurred in Camelford, England in 1988. An outcome of this event was heightened awareness that a water crisis can occur in peacetime and not only in association with terrorism. No matter how minor the contamination event or short-term the disruption of delivery of safe drinking-water, psychological, medical and public health impact could be significant.

Health risk assessment for program managers

International Nuclear Information System (INIS)

Jump, R.A.; Williamson, D.S.

1994-01-01

This paper presents the findings of a sensitivity analysis into the independent variables that determine the levels of health risks posed by buried plutonium and americium at a typical contaminated site in an arid region. Environmental Restoration Program Managers often must make decisions concerning cleanup levels, remediation alternatives, schedules, cost estimates, etc. based upon extraordinarily safe assumptions about risk assessment calculation inputs. This study reveals to the Program Manager which variables are major drivers to the calculated levels of risk posed by transuranic radionuclides and which ones have second order effects or less. The findings of this study should indicate which inputs should be the focus of attention during negotiations with regulators and of further empirical investigation

Multispectral embedding-based deep neural network for three-dimensional human pose recovery

Science.gov (United States)

Yu, Jialin; Sun, Jifeng

2018-01-01

Monocular image-based three-dimensional (3-D) human pose recovery aims to retrieve 3-D poses using the corresponding two-dimensional image features. Therefore, the pose recovery performance highly depends on the image representations. We propose a multispectral embedding-based deep neural network (MSEDNN) to automatically obtain the most discriminative features from multiple deep convolutional neural networks and then embed their penultimate fully connected layers into a low-dimensional manifold. This compact manifold can explore not only the optimum output from multiple deep networks but also the complementary properties of them. Furthermore, the distribution of each hierarchy discriminative manifold is sufficiently smooth so that the training process of our MSEDNN can be effectively implemented only using few labeled data. Our proposed network contains a body joint detector and a human pose regressor that are jointly trained. Extensive experiments conducted on four databases show that our proposed MSEDNN can achieve the best recovery performance compared with the state-of-the-art methods.

Methods for intraoperative, sterile pose-setting of patient-specific microstereotactic frames

Science.gov (United States)

Vollmann, Benjamin; Müller, Samuel; Kundrat, Dennis; Ortmaier, Tobias; Kahrs, Lüder A.

2015-03-01

This work proposes new methods for a microstereotactic frame based on bone cement fixation. Microstereotactic frames are under investigation for minimal invasive temporal bone surgery, e.g. cochlear implantation, or for deep brain stimulation, where products are already on the market. The correct pose of the microstereotactic frame is either adjusted outside or inside the operating room and the frame is used for e.g. drill or electrode guidance. We present a patientspecific, disposable frame that allows intraoperative, sterile pose-setting. Key idea of our approach is bone cement between two plates that cures while the plates are positioned with a mechatronics system in the desired pose. This paper includes new designs of microstereotactic frames, a system for alignment and first measurements to analyze accuracy and applicable load.

Making 2D face recognition more robust using AAMs for pose compensation

NARCIS (Netherlands)

Huisman, Peter; Munster, Ruud; Moro-Ellenberger, Stephanie; Veldhuis, Raymond N.J.; Bazen, A.M.

2006-01-01

The problem of pose in 2D face recognition is widely acknowledged. Commercial systems are limited to near frontal face images and cannot deal with pose deviations larger than 15 degrees from the frontal view. This is a problem, when using face recognition for surveillance applications in which

Integrating Worked Examples into Problem Posing in a Web-Based Learning Environment

Science.gov (United States)

Hsiao, Ju-Yuan; Hung, Chun-Ling; Lan, Yu-Feng; Jeng, Yoau-Chau

2013-01-01

Most students always lack of experience and perceive difficult regarding problem posing. The study hypothesized that worked examples may have benefits for supporting students' problem posing activities. A quasi-experiment was conducted in the context of a business mathematics course for examining the effects of integrating worked examples into…

Head Pose Estimation from Passive Stereo Images

DEFF Research Database (Denmark)

Breitenstein, Michael D.; Jensen, Jeppe; Høilund, Carsten

2009-01-01

function. Our algorithm incorporates 2D and 3D cues to make the system robust to low-quality range images acquired by passive stereo systems. It handles large pose variations (of ±90 ° yaw and ±45 ° pitch rotation) and facial variations due to expressions or accessories. For a maximally allowed error of 30...

Improving pandemic influenza risk assessment

Science.gov (United States)

Assessing the pandemic risk posed by specific non-human influenza A viruses remains a complex challenge. As influenza virus genome sequencing becomes cheaper, faster and more readily available, the ability to predict pandemic potential from sequence data could transform pandemic influenza risk asses...

A globally-distributed alien invasive species poses risks to United States imperiled species.

Science.gov (United States)

McClure, Meredith L; Burdett, Christopher L; Farnsworth, Matthew L; Sweeney, Steven J; Miller, Ryan S

2018-03-28

In the midst of Earth's sixth mass extinction event, non-native species are a driving factor in many imperiled species' declines. One of the most widespread and destructive alien invasive species in the world, wild pigs (Sus scrofa) threaten native species through predation, habitat destruction, competition, and disease transmission. We show that wild pigs co-occur with up to 87.2% of imperiled species in the contiguous U.S. identified as susceptible to their direct impacts, and we project increases in both the number of species at risk and the geographic extent of risks by 2025. Wild pigs may therefore present a severe threat to U.S. imperiled species, with serious implications for management of at-risk species throughout wild pigs' global distribution. We offer guidance for efficient allocation of research effort and conservation resources across species and regions using a simple approach that can be applied to wild pigs and other alien invasive species globally.

Pest risk assessment of Monilinia fructicola for the EU territory and identification and evaluation of risk management options

DEFF Research Database (Denmark)

Baker, R.; Candresse, T.; Dormannsné Simon, E.

2011-01-01

The EFSA Panel on Plant Health has delivered a pest risk assessment on the risk posed by Monilinia fructicola to the EU territory and has identified risk management options and evaluated their effectiveness in reducing the risk to plant health posed by this organism. The Panel has also analysed...... the effectiveness of the special requirements presently listed in Annex IV, Part A, Section I of Council Directive 2000/29/EC, in reducing the risk of introduction of this pest into the EU territory. The Panel concluded that the main pathways for entry into the EU territory are plant material for propagation...... of the risk assessment area. Cultural practices and control measures currently applied and competition with other Monilinia species cannot prevent the establishment of M. fructicola. The probability of spread is very likely because of the multiple ways of dispersal of the pest. The overall impact...

Improved pose and affinity predictions using different protocols tailored on the basis of data availability

Science.gov (United States)

Prathipati, Philip; Nagao, Chioko; Ahmad, Shandar; Mizuguchi, Kenji

2016-09-01

The D3R 2015 grand drug design challenge provided a set of blinded challenges for evaluating the applicability of our protocols for pose and affinity prediction. In the present study, we report the application of two different strategies for the two D3R protein targets HSP90 and MAP4K4. HSP90 is a well-studied target system with numerous co-crystal structures and SAR data. Furthermore the D3R HSP90 test compounds showed high structural similarity to existing HSP90 inhibitors in BindingDB. Thus, we adopted an integrated docking and scoring approach involving a combination of both pharmacophoric and heavy atom similarity alignments, local minimization and quantitative structure activity relationships modeling, resulting in the reasonable prediction of pose [with the root mean square deviation (RMSD) values of 1.75 Å for mean pose 1, 1.417 Å for the mean best pose and 1.85 Å for the mean all poses] and affinity (ROC AUC = 0.702 at 7.5 pIC50 cut-off and R = 0.45 for 180 compounds). The second protein, MAP4K4, represents a novel system with limited SAR and co-crystal structure data and little structural similarity of the D3R MAP4K4 test compounds to known MAP4K4 ligands. For this system, we implemented an exhaustive pose and affinity prediction protocol involving docking and scoring using the PLANTS software which considers side chain flexibility together with protein-ligand fingerprints analysis assisting in pose prioritization. This protocol through fares poorly in pose prediction (with the RMSD values of 4.346 Å for mean pose 1, 4.69 Å for mean best pose and 4.75 Å for mean all poses) and produced reasonable affinity prediction (AUC = 0.728 at 7.5 pIC50 cut-off and R = 0.67 for 18 compounds, ranked 1st among 80 submissions).

Comparison of Safety Margin Generation Concepts in Image Guided Radiotherapy to Account for Daily Head and Neck Pose Variations.

Science.gov (United States)

Stoll, Markus; Stoiber, Eva Maria; Grimm, Sarah; Debus, Jürgen; Bendl, Rolf; Giske, Kristina

2016-01-01

Intensity modulated radiation therapy (IMRT) of head and neck tumors allows a precise conformation of the high-dose region to clinical target volumes (CTVs) while respecting dose limits to organs a risk (OARs). Accurate patient setup reduces translational and rotational deviations between therapy planning and therapy delivery days. However, uncertainties in the shape of the CTV and OARs due to e.g. small pose variations in the highly deformable anatomy of the head and neck region can still compromise the dose conformation. Routinely applied safety margins around the CTV cause higher dose deposition in adjacent healthy tissue and should be kept as small as possible. In this work we evaluate and compare three approaches for margin generation 1) a clinically used approach with a constant isotropic 3 mm margin, 2) a previously proposed approach adopting a spatial model of the patient and 3) a newly developed approach adopting a biomechanical model of the patient. All approaches are retrospectively evaluated using a large patient cohort of over 500 fraction control CT images with heterogeneous pose changes. Automatic methods for finding landmark positions in the control CT images are combined with a patient specific biomechanical finite element model to evaluate the CTV deformation. The applied methods for deformation modeling show that the pose changes cause deformations in the target region with a mean motion magnitude of 1.80 mm. We found that the CTV size can be reduced by both variable margin approaches by 15.6% and 13.3% respectively, while maintaining the CTV coverage. With approach 3 an increase of target coverage was obtained. Variable margins increase target coverage, reduce risk to OARs and improve healthy tissue sparing at the same time.

Project risk as identity threat: explaining the development and consequences of risk discourse in an infrastructure project

NARCIS (Netherlands)

van Os, A.; van Berkel, F.J.F.W.; de Gilder, T.C.; van Dyck, C.; Groenewegen, P.

2015-01-01

This paper explores the role of social identity threat in risk discourse in an infrastructure project, and the consequences risk discourse has for cooperation between stakeholders. We show that risks posed a threat to the identity of the project team, resulting in a discourse focused on attributing

Modelling the Risk Posed by the Zebra Mussel Dreissena polymorpha: Italy as a Case Study.

Science.gov (United States)

Bosso, Luciano; De Conno, Carmelina; Russo, Danilo

2017-08-01

We generated a risk map to forecast the potential effects of the spreading of zebra mussels Dreissena polymorpha across the Italian territory. We assessed the invader's potential impact on rivers, lakes, watersheds and dams at a fine-grained scale and detected those more at risk that should be targeted with appropriate monitoring. We developed a MaxEnt model and employed weighted overlay analyses to detect the species' potential distribution and generate risk maps for Italy. D. polymorpha has a greater probability of occurring at low to medium altitudes in areas characterised by fluviatile deposits of major streams. Northern and central Italy appear more at risk. Some hydroelectric power dams are at high risk, while most dams for irrigation, drinkable water reservoirs and other dam types are at medium to low risk. The lakes and rivers reaches (representing likely expansion pathways) at medium-high or high risk mostly occur in northern and central Italy. We highlight the importance of modelling potential invasions on a country scale to achieve the sufficient resolution needed to develop appropriate monitoring plans and prevent the invader's harmful effects. Further high-resolution risk maps are needed for other regions partly or not yet colonised by the zebra mussel.

Modelling the Risk Posed by the Zebra Mussel Dreissena polymorpha: Italy as a Case Study

Science.gov (United States)

Bosso, Luciano; De Conno, Carmelina; Russo, Danilo

2017-08-01

We generated a risk map to forecast the potential effects of the spreading of zebra mussels Dreissena polymorpha across the Italian territory. We assessed the invader's potential impact on rivers, lakes, watersheds and dams at a fine-grained scale and detected those more at risk that should be targeted with appropriate monitoring. We developed a MaxEnt model and employed weighted overlay analyses to detect the species' potential distribution and generate risk maps for Italy. D. polymorpha has a greater probability of occurring at low to medium altitudes in areas characterised by fluviatile deposits of major streams. Northern and central Italy appear more at risk. Some hydroelectric power dams are at high risk, while most dams for irrigation, drinkable water reservoirs and other dam types are at medium to low risk. The lakes and rivers reaches (representing likely expansion pathways) at medium-high or high risk mostly occur in northern and central Italy. We highlight the importance of modelling potential invasions on a country scale to achieve the sufficient resolution needed to develop appropriate monitoring plans and prevent the invader's harmful effects. Further high-resolution risk maps are needed for other regions partly or not yet colonised by the zebra mussel.

Mobile assistant for unknown caller identification

OpenAIRE

Hribernik, Andraž

2012-01-01

The main motivation of this diploma thesis is a development of Android application, which helps user of application to find out who is the owner of unknown phone number. Data source for finding unknown phone number are free available web sources. Through the development of prototype, data from different web sources were integrated. Result of this integration is shown in Android application. Data integration includes access to semi-structured data on web portal of Phone Directory of Slovenia, ...

Risk assessments ensure safer power

Energy Technology Data Exchange (ETDEWEB)

1982-02-19

A growth industry is emerging devoted to the study and comparison of the economic, social and health risks posed by large industrial installations. Electricity generation is one area coming under particularly close scrutiny. Types of risk, ways of assessing risk and the difference between experts' analyses and the public perception of risk are given. An example of improved risk assessment helping to reduce deaths and injuries in coal mining is included.

Body-part templates for recovery of 2D human poses under occlusion

NARCIS (Netherlands)

Poppe, Ronald Walter; Poel, Mannes; Perales, F.J.; Fisher, R.B.

2008-01-01

Detection of humans and estimation of their 2D poses from a single image are challenging tasks. This is especially true when part of the observation is occluded. However, given a limited class of movements, poses can be recovered given the visible body-parts. To this end, we propose a novel template

Problem-Posing in Education: Transformation of the Practice of the Health Professional.

Science.gov (United States)

Casagrande, L. D. R.; Caron-Ruffino, M.; Rodrigues, R. A. P.; Vendrusculo, D. M. S.; Takayanagui, A. M. M.; Zago, M. M. F.; Mendes, M. D.

1998-01-01

Studied the use of a problem-posing model in health education. The model based on the ideas of Paulo Freire is presented. Four innovative experiences of teaching-learning in environmental and occupational health and patient education are reported. Notes that the problem-posing model has the capability to transform health-education practice.…

The present global financial and economic crisis poses an additional risk factor for mental health problems on the employees.

Science.gov (United States)

Avčin, Bojana Avguštin; Kučina, Andrea Užmah; Sarotar, Brigita Novak; Radovanović, Mirjana; Plesničar, Blanka Kores

2011-09-01

The global financial and economic crisis starting in 2007 led to a deterioration of several socio-economic determinants of mental health. The aim of this cross-sectional study was to examine the impact of the present economic crisis on the depression and anxiety levels of the employed in the private and public sector in Slovenia. Altogether 1592 employees completed an internet based self-reported questionnaire. Data about perceived impact of the economic crisis, several socio-demographic, socioeconomic, and health parameters were collected. Depression symptoms were assessed by the Center for Epidemiological Studies-Depression Scale and anxiety symptoms by the Spielberger State-Inventory. Regression models were used 1) to explore the associations of the economic crisis with the level of depression and anxiety symptoms while controlling for some sociodemographic and work characteristic variables, and 2) to understand the relationship between some potentially important socioeconomic variables and the perception of the economic crisis. Depressive and anxiety scores were significantly increased among 590 (46.6%) employees being affected by the economic crisis. The level of depressive symptoms was significantly associated with perceived impact by the crisis, recent sick leave, reported injuries sustained at work, benzodiazepine and analgesic use, the lack of emotional support, and trust in crisis telephone lines. The level of anxiety symptoms yielded the robust association with the level of depression symptoms, reported injuries sustained on the way to work and education. The economic crisis poses an additional risk factor for mental health problems which clinicians should internalize and become more aware of them. Symptoms of depression and anxiety can be masked in high-utilizers of medical care with physical complaints or psychoactive drug use.

Collaborative Random Faces-Guided Encoders for Pose-Invariant Face Representation Learning.

Science.gov (United States)

Shao, Ming; Zhang, Yizhe; Fu, Yun

2018-04-01

Learning discriminant face representation for pose-invariant face recognition has been identified as a critical issue in visual learning systems. The challenge lies in the drastic changes of facial appearances between the test face and the registered face. To that end, we propose a high-level feature learning framework called "collaborative random faces (RFs)-guided encoders" toward this problem. The contributions of this paper are three fold. First, we propose a novel supervised autoencoder that is able to capture the high-level identity feature despite of pose variations. Second, we enrich the identity features by replacing the target values of conventional autoencoders with random signals (RFs in this paper), which are unique for each subject under different poses. Third, we further improve the performance of the framework by incorporating deep convolutional neural network facial descriptors and linking discriminative identity features from different RFs for the augmented identity features. Finally, we conduct face identification experiments on Multi-PIE database, and face verification experiments on labeled faces in the wild and YouTube Face databases, where face recognition rate and verification accuracy with Receiver Operating Characteristic curves are rendered. In addition, discussions of model parameters and connections with the existing methods are provided. These experiments demonstrate that our learning system works fairly well on handling pose variations.

"You're dealing with an emotionally charged individual...": an industry perspective on the challenges posed by medical tourists' informal caregiver-companions.

Science.gov (United States)

Casey, Victoria; Crooks, Valorie A; Snyder, Jeremy; Turner, Leigh

2013-07-26

Patients engage in medical tourism when they privately obtain a medical care abroad. Previous research shows that many medical tourists travel abroad with friends and family members who provide support and assistance. Meanwhile, very little is known about this important stakeholder group, referred to here as caregiver-companions. In this article we examine the challenges that can be posed by caregiver-companions and the overall practice of informal caregiving in medical tourism from an industry perspective. Specifically, we report on the findings of interviews conducted with international patient coordinators (IPCs) who work at destination facilities. IPCs come into regular contact with caregiver-companions in their professional positions and thus are ideally suited to comment on trends they have observed among this stakeholder group as well as the challenges they can pose to medical tourists, health workers, and facilities. We conducted 20 semi-structured interviews with 21 IPCs from 16 different facilities across nine countries. Topics probed in the interviews included caregiver-companion roles, IPCs' and others' interaction with caregiver-companions, and potential health and safety risks posed to medical tourists and caregiver-companions. Thematic analysis of the verbatim transcripts was employed. Although most participants encouraged medical tourists to travel with a caregiver-companion, many challenges associated with caregiver-companions were identified. Three themes best characterize the challenges that emerged: (1) caregiver-companions require time, attention and resources; (2) caregiver-companions can disrupt the provision of quality care; and (3) caregiver-companions can be exposed to risks. IPCs pointed out that caregiver-companions may, for example, have a negative impact on the patient through cost of accompaniment or inadequate care provision. Caregiver-companions may also create unanticipated or extra work for IPCs, as additional clients and by

Pose Estimation of Interacting People using Pictorial Structures

DEFF Research Database (Denmark)

Fihl, Preben; Moeslund, Thomas B.

2010-01-01

Pose estimation of people have had great progress in recent years but so far research has dealt with single persons. In this paper we address some of the challenges that arise when doing pose estimation of interacting people. We build on the pictorial structures framework and make important...... contributions by combining color-based appearance and edge information using a measure of the local quality of the appearance feature. In this way we not only combine the two types of features but dynamically find the optimal weighting of them. We further enable the method to handle occlusions by searching...... a foreground mask for possible occluded body parts and then applying extra strong kinematic constraints to find the true occluded body parts. The effect of applying our two contributions are show through both qualitative and quantitative tests and show a clear improvement on the ability to correctly localize...

Generalized Hough transform based time invariant action recognition with 3D pose information

Science.gov (United States)

Muench, David; Huebner, Wolfgang; Arens, Michael

2014-10-01

Human action recognition has emerged as an important field in the computer vision community due to its large number of applications such as automatic video surveillance, content based video-search and human robot interaction. In order to cope with the challenges that this large variety of applications present, recent research has focused more on developing classifiers able to detect several actions in more natural and unconstrained video sequences. The invariance discrimination tradeoff in action recognition has been addressed by utilizing a Generalized Hough Transform. As a basis for action representation we transform 3D poses into a robust feature space, referred to as pose descriptors. For each action class a one-dimensional temporal voting space is constructed. Votes are generated from associating pose descriptors with their position in time relative to the end of an action sequence. Training data consists of manually segmented action sequences. In the detection phase valid human 3D poses are assumed as input, e.g. originating from 3D sensors or monocular pose reconstruction methods. The human 3D poses are normalized to gain view-independence and transformed into (i) relative limb-angle space to ensure independence of non-adjacent joints or (ii) geometric features. In (i) an action descriptor consists of the relative angles between limbs and their temporal derivatives. In (ii) the action descriptor consists of different geometric features. In order to circumvent the problem of time-warping we propose to use a codebook of prototypical 3D poses which is generated from sample sequences of 3D motion capture data. This idea is in accordance with the concept of equivalence classes in action space. Results of the codebook method are presented using the Kinect sensor and the CMU Motion Capture Database.

Toxic-metabolic Risk Factors in Pediatric Pancreatitis: Recommendations for Diagnosis, Management, and Future Research.

Science.gov (United States)

Husain, Sohail Z; Morinville, Veronique; Pohl, John; Abu-El-Haija, Maisam; Bellin, Melena D; Freedman, Steve; Hegyi, Peter; Heyman, Melvin B; Himes, Ryan; Ooi, Chee Y; Schwarzenberg, Sarah J; Usatin, Danielle; Uc, Aliye

2016-04-01

Pancreatitis in children can result from metabolic and toxic risk factors, but the evidence linking these factors is sparse. We review the evidence for association or causality of these risk factors in pancreatitis, discuss management strategies, and their rationale. We conducted a review of the pediatric pancreatitis literature with respect to the following risk factors: hyperlipidemia, hypercalcemia, chronic renal failure, smoking exposure, alcohol, and medications. Areas of additional research were identified. Hypertriglyceridemia of 1000 mg/dL or greater poses an absolute risk for pancreatitis; persistent elevations of calcium are predisposing. Further research is necessary to determine whether end-stage renal disease leads to increased pancreatitis in children similar to adults. It is unknown whether cigarette smoking exposure, which clearly increases risk in adults, also increases risk in children. The role of alcohol in pediatric pancreatitis, whether direct or modifying, needs to be elucidated. The evidence supporting most cases of medication-induced pancreatitis is poor. Drug structure, improper handling of drug by host, and bystander status may be implicated. Other pancreatitis risk factors must be sought in all cases. The quality of evidence supporting causative role of various toxic and metabolic factors in pediatric pancreatitis is variable. Careful phenotyping is essential, including search for other etiologic risk factors. Directed therapy includes correction/removal of any agent identified, and general supportive measures. Further research is necessary to improve our understanding of these pancreatitis risk factors in children.

The Effects of Problem Posing on Student Mathematical Learning: A Meta-Analysis

Science.gov (United States)

Rosli, Roslinda; Capraro, Mary Margaret; Capraro, Robert M.

2014-01-01

The purpose of the study was to meta-synthesize research findings on the effectiveness of problem posing and to investigate the factors that might affect the incorporation of problem posing in the teaching and learning of mathematics. The eligibility criteria for inclusion of literature in the meta-analysis was: published between 1989 and 2011,…

Trotting Gait of a Quadruped Robot Based on the Time-Pose Control Method

Directory of Open Access Journals (Sweden)

Cai RunBin

2013-02-01

Full Text Available We present the Time-Pose control method for the trotting gait of a quadruped robot on flat ground and up a slope. The method, with brief control structure, real-time operation ability and high adaptability, divides quadruped robot control into gait control and pose control. Virtual leg and intuitive controllers are introduced to simplify the model and generate the trajectory of mass centre and location of supporting legs in gait control, while redundancy optimization is used for solving the inverse kinematics in pose control. The models both on flat ground and up a slope are fully analysed, and different kinds of optimization methods are compared using the manipulability measure in order to select the best option. Simulations are performed, which prove that the Time-Pose control method is realizable for these two kinds of environment.

Client experiences with perinatal healthcare for high-risk and low-risk women

NARCIS (Netherlands)

van Stenus, Cherelle M.V.; Boere-Boonekamp, Magda M.; Kerkhof, Erna F.G.M.; Need, Ariana

2018-01-01

Problem: It is unknown if client experiences with perinatal healthcare differ between low-risk and high-risk women. Background: In the Netherlands, risk selection divides pregnant women into low- and high-risk groups. Receiving news that a pregnancy or childbirth has an increased likelihood of

Robust Pose Estimation using the SwissRanger SR-3000 Camera

DEFF Research Database (Denmark)

Gudmundsson, Sigurjon Arni; Larsen, Rasmus; Ersbøll, Bjarne Kjær

2007-01-01

In this paper a robust method is presented to classify and estimate an objects pose from a real time range image and a low dimensional model. The model is made from a range image training set which is reduced dimensionally by a nonlinear manifold learning method named Local Linear Embedding (LLE)......). New range images are then projected to this model giving the low dimensional coordinates of the object pose in an efficient manner. The range images are acquired by a state of the art SwissRanger SR-3000 camera making the projection process work in real-time....

Perspectives on risk and the unforeseen

International Nuclear Information System (INIS)

Haugen, Stein; Vinnem, Jan Erik

2015-01-01

Black swans have been discussed lately. Some recent contributions to the understanding of black swans have been provided by Aven [1] and Aven and Krohn [3]. It is important to be aware of events which may come as complete surprise, which creates uncertainty in the risk assessment. This is consistent with the proposed revision of the definition of risk by Petroleum Safety Authority (PSA) [Norway]. But we should at the same time also try to look beyond this and see how we can use this concept to avoid serious accidents or at least reduce the consequences should accidents occur. In this paper we proposed to restrict the black swan concept to unknown unknowns. Cases illustrate how the wider definition may lead to misleading and unfortunate effects that will not lead to good risk management practices. The wider definitions proposed by Aven & Krohn are proposed to be counterproductive if seen in a risk management context. - Highlights: • Black swans in a risk management context should be reserved for “unknown unknowns”. • Definitions by Aven and Krohn to include risks beyond “unknown unknowns” is unfortunate. • Cases illustrate how definition by Aven and Krohn may give misleading & unfortunate effects • Oil companies have for a long time neglected the uncertainty aspect of the risk element. • Proposed revision of the regulations by PSA is appropriate

Binary classification posed as a quadratically constrained quadratic ...

Indian Academy of Sciences (India)

Binary classification is posed as a quadratically constrained quadratic problem and solved using the proposed method. Each class in the binary classification problem is modeled as a multidimensional ellipsoid to forma quadratic constraint in the problem. Particle swarms help in determining the optimal hyperplane or ...

Developing teachers' subject didactic competence through problem posing

Czech Academy of Sciences Publication Activity Database

Tichá, Marie; Hošpesová, A.

2013-01-01

Roč. 83, č. 1 (2013), s. 133-143 ISSN 0013-1954 Institutional support: RVO:67985840 Keywords : professional development * primary school teachers * problem posing Subject RIV: AM - Education Impact factor: 0.639, year: 2013 http://link.springer.com/article/10.1007%2Fs10649-012-9455-1

How sulfate-rich mine drainage affected aquatic ecosystem degradation in northeastern China, and potential ecological risk.

Science.gov (United States)

Zhao, Qian; Guo, Fen; Zhang, Yuan; Ma, Shuqin; Jia, Xiaobo; Meng, Wei

2017-12-31

Mining activity is an increasingly important stressor for freshwater ecosystems. However, the mechanism on how sulfate-rich mine drainage affects freshwater ecosystems is largely unknown, and its potential ecological risk has not been assessed so far. During 2009-2016, water and macroinvertebrate samples from 405 sample sites were collected along the mine drainage gradient from circum-neutral to alkaline waters in Hun-Tai River, Northeastern China. Results of linear regressions showed that sulfate-rich mine drainage was significantly positively correlated with the constituents typically derived from rock weathering (Ca 2+ , Mg 2+ and HCO 3 - +CO 3 2- ); the diversity of intolerant stream macroinvertebrates exhibited a steep decline along the gradient of sulfate-rich mine drainage. Meanwhile, stressor-response relationships between sulfate-rich mine drainage and macroinvertebrate communities were explored by two complementary statistical approaches in tandem (Threshold Indicator Taxa Analysis and the field-based method developed by USEPA). Results revealed that once stream sulfate concentrations in mine drainage exceeded 35mg/L, significant decline in the abundance of intolerant macroinvertebrate taxa occurred. An assessment of ecological risk posed by sulfate-rich mine drainage was conducted based on a tiered approach consisting of simple deterministic method (Hazard Quotient, HQ) to probabilistic method (Joint Probability Curve, JPC). Results indicated that sulfate-rich mine drainage posed a potential risk, and 64.62-84.88% of surface waters in Hun-Tai River exist serious risk while 5% threshold (HC 05 ) and 1% threshold (HC 01 ) were set up to protect macroinvertebrates, respectively. This study provided us a better understanding on the impacts of sulfate-rich mine drainage on freshwater ecosystems, and it would be helpful for future catchment management to protect streams from mining activity. Copyright © 2017. Published by Elsevier B.V.

MoCha: Molecular Characterization of Unknown Pathways.

Science.gov (United States)

Lobo, Daniel; Hammelman, Jennifer; Levin, Michael

2016-04-01

Automated methods for the reverse-engineering of complex regulatory networks are paving the way for the inference of mechanistic comprehensive models directly from experimental data. These novel methods can infer not only the relations and parameters of the known molecules defined in their input datasets, but also unknown components and pathways identified as necessary by the automated algorithms. Identifying the molecular nature of these unknown components is a crucial step for making testable predictions and experimentally validating the models, yet no specific and efficient tools exist to aid in this process. To this end, we present here MoCha (Molecular Characterization), a tool optimized for the search of unknown proteins and their pathways from a given set of known interacting proteins. MoCha uses the comprehensive dataset of protein-protein interactions provided by the STRING database, which currently includes more than a billion interactions from over 2,000 organisms. MoCha is highly optimized, performing typical searches within seconds. We demonstrate the use of MoCha with the characterization of unknown components from reverse-engineered models from the literature. MoCha is useful for working on network models by hand or as a downstream step of a model inference engine workflow and represents a valuable and efficient tool for the characterization of unknown pathways using known data from thousands of organisms. MoCha and its source code are freely available online under the GPLv3 license.

Pesticide Risk Communication, Risk Perception, and Self-Protective Behaviors among Farmworkers in California's Salinas Valley

Science.gov (United States)

Cabrera, Nolan L.; Leckie, James O.

2009-01-01

Agricultural pesticide use is the highest of any industry, yet there is little research evaluating farmworkers' understandings of the health risks chemical exposure poses. This study examines pesticide education, risk perception, and self-protective behaviors among farmworkers in California's Salinas Valley. Fifty current and former farmworkers…

Inertial measurement unit–based iterative pose compensation algorithm for low-cost modular manipulator

Directory of Open Access Journals (Sweden)

Yunhan Lin

2016-01-01

Full Text Available It is a necessary mean to realize the accurate motion control of the manipulator which uses end-effector pose correction method and compensation method. In this article, first, we established the kinematic model and error model of the modular manipulator (WUST-ARM, and then we discussed the measurement methods and precision of the inertial measurement unit sensor. The inertial measurement unit sensor is mounted on the end-effector of modular manipulator, to get the real-time pose of the end-effector. At last, a new inertial measurement unit–based iterative pose compensation algorithm is proposed. By applying this algorithm in the pose compensation experiment of modular manipulator which is composed of low-cost rotation joints, the results show that the inertial measurement unit can obtain a higher precision when in static state; it will accurately feedback to the control system with an accurate error compensation angle after a brief delay when the end-effector moves to the target point, and after compensation, the precision errors of roll angle, pitch angle, and yaw angle are reached at 0.05°, 0.01°, and 0.27° respectively. It proves that this low-cost method provides a new solution to improve the end-effector pose of low-cost modular manipulator.

Health Issues: Do Cell Phones Pose a Health Hazard?

Science.gov (United States)

... Procedures Home, Business, and Entertainment Products Cell Phones Health Issues Share Tweet Linkedin Pin it More sharing ... it Email Print Do cell phones pose a health hazard? Many people are concerned that cell phone ...

Pose Self-Measurement of Noncooperative Spacecraft Based on Solar Panel Triangle Structure

Directory of Open Access Journals (Sweden)

Jingzhou Song

2015-01-01

Full Text Available Aiming at the recognition and location of noncooperative spacecraft, this paper presents a monocular vision pose measurement method based on solar triangle structure. First of all, an autonomous recognition algorithm of feature structure based on sliding window Hough transformation (SWHT and inscribed circle of a triangle is proposed, and the image coordinates of feature points on the triangle can be obtained relying on this algorithm, combined with the P4P algorithm and the structure of spacecraft, calculating the relative pose of target expressed by rotation and translation matrix. The whole algorithm can be loaded into the prewritten onboard program, which will get the autocomplete feature structure extraction and relative pose measurement without human intervention, and this method does not need to mount any markers on the target. Then compare the measured values with the accurate value of the laser tracker, so that a conclusion can be drawn that the maximum position error is lower than 5% and the rotation error is lower than 4%, which meets the requirements of noncooperative spacecraft’s pose measurement for observations, tracking, and docking in the final rendezvous phase.

Mining Key Skeleton Poses with Latent SVM for Action Recognition

Directory of Open Access Journals (Sweden)

Xiaoqiang Li

2017-01-01

Full Text Available Human action recognition based on 3D skeleton has become an active research field in recent years with the recently developed commodity depth sensors. Most published methods analyze an entire 3D depth data, construct mid-level part representations, or use trajectory descriptor of spatial-temporal interest point for recognizing human activities. Unlike previous work, a novel and simple action representation is proposed in this paper which models the action as a sequence of inconsecutive and discriminative skeleton poses, named as key skeleton poses. The pairwise relative positions of skeleton joints are used as feature of the skeleton poses which are mined with the aid of the latent support vector machine (latent SVM. The advantage of our method is resisting against intraclass variation such as noise and large nonlinear temporal deformation of human action. We evaluate the proposed approach on three benchmark action datasets captured by Kinect devices: MSR Action 3D dataset, UTKinect Action dataset, and Florence 3D Action dataset. The detailed experimental results demonstrate that the proposed approach achieves superior performance to the state-of-the-art skeleton-based action recognition methods.

LEVELING STUDENTS’ CREATIVE THINKING IN SOLVING AND POSING MATHEMATICAL PROBLEM

Directory of Open Access Journals (Sweden)

Tatag Yuli Eko Siswono

2010-07-01

Full Text Available Many researchers assume that people are creative, but their degree ofcreativity is different. The notion of creative thinking level has beendiscussed .by experts. The perspective of mathematics creative thinkingrefers to a combination of logical and divergent thinking which is basedon intuition but has a conscious aim. The divergent thinking is focusedon flexibility, fluency, and novelty in mathematical problem solving andproblem posing. As students have various backgrounds and differentabilities, they possess different potential in thinking patterns,imagination, fantasy and performance; therefore, students have differentlevels of creative thinking. A research study was conducted in order todevelop a framework for students’ levels of creative thinking inmathematics. This research used a qualitative approach to describe thecharacteristics of the levels of creative thinking. Task-based interviewswere conducted to collect data with ten 8thgrade junior secondary schoolstudents. The results distinguished five levels of creative thinking,namely level 0 to level 4 with different characteristics in each level.These differences are based on fluency, flexibility, and novelty inmathematical problem solving and problem posing.Keywords: student’s creative thinking, problem posing, flexibility,fluency, novelty DOI: http://dx.doi.org/10.22342/jme.1.1.794.17-40

Comparison On Matching Methods Used In Pose Tracking For 3D Shape Representation

Directory of Open Access Journals (Sweden)

Khin Kyu Kyu Win

2017-01-01

Full Text Available In this work three different algorithms such as Brute Force Delaunay Triangulation and k-d Tree are analyzed on matching comparison for 3D shape representation. It is intended for developing the pose tracking of moving objects in video surveillance. To determine 3D pose of moving objects some tracking system may require full 3D pose estimation of arbitrarily shaped objects in real time. In order to perform 3D pose estimation in real time each step in the tracking algorithm must be computationally efficient. This paper presents method comparison for the computationally efficient registration of 3D shapes including free-form surfaces. Matching of free-form surfaces are carried out by using geometric point matching algorithm ICP. Several aspects of the ICP algorithm are investigated and analyzed by using specified surface setup. The surface setup processed in this system is represented by simple geometric primitive dealing with objects of free-from shape. Considered representations are a cloud of points.

Pose measurement method with six parameters for microassembly based on an optical micrometer

Science.gov (United States)

Ye, Xin; Wang, Qiang; Zhang, Zhi-jing; Sun, Yuan; Zhang, Xiao-feng

2009-07-01

This paper presents a new pose measurement method of microminiature parts that is capable of transforming one dimension (1D) contour size obtained by optical micrometer to three dimension (3D) data with six parameters for microassembly. Pose measurement is one of the most important processes for microminiature parts' alignment and insertion in microassembly. During the past few years, researchers have developed their microassembly systems focusing on visual identification to obtain two or three dimension data with no more than three parameters. Scanning electronic microscope (SEM), optical microscope, and stereomicroscope are applied in their systems. However, as structures of microminiature parts become increasingly complex, six parameters to represent their position and orientation are specifically needed. Firstly, The pose measurement model is established based on the introduction of measuring objects and measuring principle of optical micrometer. The measuring objects are microminiature parts with complex 3D structure. Two groups of two dimension (2D) data are gathered at two different measurement positions. Then part pose with 6 parameters is calculated, including 3 position parameters of feature point of the part and 3 orientation parameters of the part axis. Secondly, pose measurement process for a small shaft, vertical orientation determination, and position parameters obtaining are presented. 2D data is gathered by scanning the generatrix of the part, and valid data is extracted and saved in arrays. A vertical orientation criterion is proposed to determine whether the part is parallel to the Z-axis of the coordinate. If not, 2D data will be fixed into a linear equation using least square algorithm. Then orientation parameters are calculated. Center of Part End (CPE) is selected as feature point of the part, and its position parameters are extracted form two group of 2D data. Finally, a fast pose measurement device is developed and representative

Security Measurement for Unknown Threats Based on Attack Preferences

Directory of Open Access Journals (Sweden)

Lihua Yin

2018-01-01

Full Text Available Security measurement matters to every stakeholder in network security. It provides security practitioners the exact security awareness. However, most of the works are not applicable to the unknown threat. What is more, existing efforts on security metric mainly focus on the ease of certain attack from a theoretical point of view, ignoring the “likelihood of exploitation.” To help administrator have a better understanding, we analyze the behavior of attackers who exploit the zero-day vulnerabilities and predict their attack timing. Based on the prediction, we propose a method of security measurement. In detail, we compute the optimal attack timing from the perspective of attacker, using a long-term game to estimate the risk of being found and then choose the optimal timing based on the risk and profit. We design a learning strategy to model the information sharing mechanism among multiattackers and use spatial structure to model the long-term process. After calculating the Nash equilibrium for each subgame, we consider the likelihood of being attacked for each node as the security metric result. The experiment results show the efficiency of our approach.

Combining Front Vehicle Detection with 3D Pose Estimation for a Better Driver Assistance

Directory of Open Access Journals (Sweden)

Yu Peng

2012-09-01

Full Text Available Driver assistant systems enhance traffic safety and efficiency. The accurate 3D pose of a front vehicle can help a driver to make the right decision on the road. We propose a novel real-time system to estimate the 3D pose of the front vehicle. This system consists of two parallel threads: vehicle rear tracking and mapping. The vehicle rear is first identified in the video captured by an onboard camera, after license plate localization and foreground extraction. The 3D pose estimation technique is then employed with respect to the extracted vehicle rear. Most current 3D pose estimation techniques need prior models or a stereo initialization with user cooperation. It is extremely difficult to obtain prior models due to the varying appearance of vehicles' rears. Moreover, it is unsafe to ask for drivers' cooperation when a vehicle is running. In our system, two initial keyframes for stereo algorithms are automatically extracted by vehicle rear detection and tracking. Map points are defined as a collection of point features extracted from the vehicle's rear with their 3D information. These map points are inferences that relate the 2D features detected in following vehicles' rears with the 3D world. The relative 3D pose of the onboard camera to the front vehicle rear is then estimated through matching the map points with point features detected on the front vehicle rear. We demonstrate the capabilities of our system by testing on real-time and synthesized videos. In order to make the experimental analysis visible, we demonstrated an estimated 3D pose through augmented reality, which needs accurate and real-time 3D pose estimation.

Determination of the origin of unknown irradiated nuclear fuel.

Science.gov (United States)

Nicolaou, G

2006-01-01

An isotopic fingerprinting method is presented to determine the origin of unknown nuclear material with forensic importance. Spent nuclear fuel of known origin has been considered as the 'unknown' nuclear material in order to demonstrate the method and verify its prediction capabilities. The method compares, using factor analysis, the measured U, Pu isotopic compositions of the 'unknown' material with U, Pu isotopic compositions simulating well known spent fuels from a range of commercial nuclear power stations. Then, the 'unknown' fuel has the same origin as the commercial fuel with which it exhibits the highest similarity in U, Pu compositions.

Determination of the origin of unknown irradiated nuclear fuel

International Nuclear Information System (INIS)

Nicolaou, G.

2006-01-01

An isotopic fingerprinting method is presented to determine the origin of unknown nuclear material with forensic importance. Spent nuclear fuel of known origin has been considered as the 'unknown' nuclear material in order to demonstrate the method and verify its prediction capabilities. The method compares, using factor analysis, the measured U, Pu isotopic compositions of the 'unknown' material with U, Pu isotopic compositions simulating well known spent fuels from a range of commercial nuclear power stations. Then, the 'unknown' fuel has the same origin as the commercial fuel with which it exhibits the highest similarity in U, Pu compositions

Coding ill-defined and unknown cause of death is 13 times more frequent in Denmark than in Finland

DEFF Research Database (Denmark)

Ylijoki-Sørensen, Seija; Sajantila, Antti; Lalu, Kaisa

2014-01-01

Exact cause and manner of death determination improves legislative safety for the individual and for society and guides aspects of national public health. In the International Classification of Diseases, codes R00-R99 are used for "symptoms, signs and abnormal clinical and laboratory findings......, not elsewhere classified" designated as "ill-defined" or "with unknown etiology". The World Health Organisation recommends avoiding the use of ill-defined and unknown causes of death in the death certificate as this terminology does not give any information concerning the possible conditions that led...... autopsy. Our study suggests that if all deaths in all age groups with unclear cause of death were systematically investigated with a forensic autopsy, only 2-3/1000 deaths per year would be coded as an ill-defined and unknown cause of death in national mortality statistics. At the same time the risk...

Perbedaan Keterampilan Pemecahan Masalah pada Pembelajaran Fisika Menggunakan Metode Problem Posing dan Problem Solving

OpenAIRE

Rahman, Adetya; Hartini, Sri; An'nur, Syubhan

2015-01-01

Teachers should be able to choose the method of learning that can help students in learning physics, namely the method of problem posing and problem solving method. The purposes of this study are : (1) describe the learning physics skills by using problem posing method, (2) describe the learning physics skills by using problem solving method, and (3) know difference between learning physics skills by using problem posing method and problem solving method in class XI of Science SMAN 6 Banjarma...

Function analysis of unknown genes

DEFF Research Database (Denmark)

Rogowska-Wrzesinska, A.

2002-01-01

  This thesis entitled "Function analysis of unknown genes" presents the use of proteome analysis for the characterisation of yeast (Saccharomyces cerevisiae) genes and their products (proteins especially those of unknown function). This study illustrates that proteome analysis can be used...... to describe different aspects of molecular biology of the cell, to study changes that occur in the cell due to overexpression or deletion of a gene and to identify various protein modifications. The biological questions and the results of the described studies show the diversity of the information that can...... genes and proteins. It reports the first global proteome database collecting 36 yeast single gene deletion mutants and selecting over 650 differences between analysed mutants and the wild type strain. The obtained results show that two-dimensional gel electrophoresis and mass spectrometry based proteome...

The Effect of Problem Solving and Problem Posing Models and Innate Ability to Students Achievement

Directory of Open Access Journals (Sweden)

Ratna Kartika Irawati

2015-04-01

Full Text Available Pengaruh Model Problem Solving dan Problem Posing serta Kemampuan Awal terhadap Hasil Belajar Siswa   Abstract: Chemistry concepts understanding features abstract quality and requires higher order thinking skills. Yet, the learning on chemistry has not boost the higher order thinking skills of the students. The use of the learning model of Problem Solving and Problem Posing in observing the innate ability of the student is expected to resolve the issue. This study aims to determine the learning model which is effective to improve the study of the student with different level of innate ability. This study used the quasi-experimental design. The research data used in this research is the quiz/test of the class which consist of 14 multiple choice questions and 5 essay questions. The data analysis used is ANOVA Two Ways. The results showed that Problem Posing is more effective to improve the student compared to Problem Solving, students with high level of innate ability have better outcomes in learning rather than the students with low level of innate ability after being applied with the Problem solving and Problem posing model, further, Problem Solving and Problem Posing is more suitable to be applied to the students with high level of innate ability. Key Words: problem solving, problem posing, higher order thinking skills, innate ability, learning outcomes   Abstrak: Pemahaman konsep-konsep kimia yang bersifat abstrak membutuhkan keterampilan berpikir tingkat tinggi. Pembelajaran kimia belum mendorong siswa melakukan keterampilan berpikir tingkat tinggi. Penggunaan model pembelajaran Problem Solving dan Problem Posing dengan memperhatikan kemampuan awal siswa diduga dapat mengatasi masalah tersebut. Penelitian ini bertujuan untuk mengetahui model pembelajaran yang efektif dalam meningkatkan hasil belajar dengan kemampuan awal siswa yang berbeda. Penelitian ini menggunakan rancangan eksperimen semu. Data penelitian menggunakan tes hasil belajar

Fraction Multiplication and Division Word Problems Posed by Different Years of Pre-Service Elementary Mathematics Teachers

Directory of Open Access Journals (Sweden)

Tuba Aydogdu Iskenderoglu

2018-04-01

Full Text Available It is important for pre-service teachers to know the conceptual difficulties they have experienced regarding the concepts of multiplication and division in fractions and problem posing is a way to learn these conceptual difficulties. Problem posing is a synthetic activity that fundamentally has multiple answers. The purpose of this study is to analyze the multiplication and division of fractions problems posed by pre-service elementary mathematics teachers and to investigate how the problems posed change according to the year of study the pre-service teachers are in. The study employed developmental research methods. A total of 213 pre-service teachers enrolled in different years of the Elementary Mathematics Teaching program at a state university in Turkey took part in the study. The “Problem Posing Test” was used as the data collecting tool. In this test, there are 3 multiplication and 3 division operations. The data were analyzed using qualitative descriptive analysis. The findings suggest that, regardless of the year, pre-service teachers had more conceptual difficulties in problem posing about the division of fractions than in problem posing about the multiplication of fractions.

Meanings Given to Algebraic Symbolism in Problem-Posing

Science.gov (United States)

Cañadas, María C.; Molina, Marta; del Río, Aurora

2018-01-01

Some errors in the learning of algebra suggest that students might have difficulties giving meaning to algebraic symbolism. In this paper, we use problem posing to analyze the students' capacity to assign meaning to algebraic symbolism and the difficulties that students encounter in this process, depending on the characteristics of the algebraic…

Impact of Hydrogeological Uncertainty on Estimation of Environmental Risks Posed by Hydrocarbon Transportation Networks

Science.gov (United States)

Ciriello, V.; Lauriola, I.; Bonvicini, S.; Cozzani, V.; Di Federico, V.; Tartakovsky, Daniel M.

2017-11-01

Ubiquitous hydrogeological uncertainty undermines the veracity of quantitative predictions of soil and groundwater contamination due to accidental hydrocarbon spills from onshore pipelines. Such predictions, therefore, must be accompanied by quantification of predictive uncertainty, especially when they are used for environmental risk assessment. We quantify the impact of parametric uncertainty on quantitative forecasting of temporal evolution of two key risk indices, volumes of unsaturated and saturated soil contaminated by a surface spill of light nonaqueous-phase liquids. This is accomplished by treating the relevant uncertain parameters as random variables and deploying two alternative probabilistic models to estimate their effect on predictive uncertainty. A physics-based model is solved with a stochastic collocation method and is supplemented by a global sensitivity analysis. A second model represents the quantities of interest as polynomials of random inputs and has a virtually negligible computational cost, which enables one to explore any number of risk-related contamination scenarios. For a typical oil-spill scenario, our method can be used to identify key flow and transport parameters affecting the risk indices, to elucidate texture-dependent behavior of different soils, and to evaluate, with a degree of confidence specified by the decision-maker, the extent of contamination and the correspondent remediation costs.

Polymorphisms in apolipoprotein B and risk of ischemic stroke

DEFF Research Database (Denmark)

Benn, Marianne; Nordestgaard, Børge G; Jensen, Jan Skov

2007-01-01

Apolipoprotein B levels associate with risk of ischemic stroke. APOB polymorphisms may influence levels of apolipoprotein B and low-density lipoprotein (LDL), but whether they associate with risk of ischemic stroke is unknown.......Apolipoprotein B levels associate with risk of ischemic stroke. APOB polymorphisms may influence levels of apolipoprotein B and low-density lipoprotein (LDL), but whether they associate with risk of ischemic stroke is unknown....

The rarity of "unusual" [corrected] dispositions of victim bodies: staging and posing.

Science.gov (United States)

Keppel, Robert D; Weis, Joseph G

2004-11-01

The act of leaving a victim's body in an unusual position is a conscious criminal action by an offender to thwart an investigation, shock the finder and investigators of the crime scene, or give perverted pleasure to the killer. The unusual position concepts of posing and staging a murder victim have been documented thoroughly and have been accepted by the courts as a definable phenomenon. One staging case and one posing case are outlined and reveal characteristics of those homicides. From the Washington State Attorney General's Homicide Investigation and Tracking System's database on murder covering the years 1981-2000 (a total of 5,224 cases), the relative frequency of unusual body dispositions is revealed as a very rare occurrence. Only 1.3% of victims are left in an unusual position, with 0.3% being posed and 0.1% being staged. The characteristics of these types of murders also set them apart: compared to all other murders, in staged murders the victims and killers are, on average, older. All victims and offenders in the staged murders are white, with victims being disproportionately white in murders with any kind of unusual body disposition. Likewise, females stand out as victims when the body is posed, staged, or left in other unusual positions. Whereas posed bodies are more likely to include sexual assault, often in serial murders, there is no evidence of either in the staged cases. Lastly, when a body is left in an unusual position, binding is more likely, as well as the use of more "hands on" means of killing the victim, such as stabbing or cutting weapons, bludgeons, ligatures, or hands and feet.

Considering Environmental and Occupational Stressors in Cumulative Risk Assessments

Science.gov (United States)

While definitions vary across the global scientific community, cumulative risk assessments (CRAs) typically are described as exhibiting a population focus and analyzing the combined risks posed by multiple stressors. CRAs also may consider risk management alternatives as an anal...

Organizational Conditions for Dealing with The Unknown Unknown Illustrated by how a Dutch water management authority is preparing for climate change

NARCIS (Netherlands)

Termeer, Catrien J. A. M.; van den Brink, Margo A.

2013-01-01

The central question of this article is the extent to which organizations, governmental authorities in particular, are able to deal with the unknown unknown. Drawing on Weick's work on sensemaking, we introduce seven organizational conditions that can facilitate organizations to be reliable under

Does a triplet birth pose a special risk for infant development? Assessing cognitive development in relation to intrauterine growth and mother-infant interaction across the first 2 years.

Science.gov (United States)

Feldman, Ruth; Eidelman, Arthur I

2005-02-01

To examine whether a triplet birth per se poses a risk to the development of infants' cognitive competencies and to the mother-infant relationship. Twenty-three sets of triplets were matched with 23 sets of twins and 23 singleton infants (n = 138) with respect to gestational age, birth weight, and medical and demographic features. Infants with perinatal asphyxia, intraventricular hemorrhage of grade 3 or 4, periventricular leukomalacia, or central nervous system infection were excluded from the study. At 6, 12, and 24 months of age, mother-infant interaction was observed and infants' cognitive development was tested with the Bayley II test. Mothers of triplets displayed lower levels of sensitivity at 6, 12, and 24 months and infants were less socially involved at 6 and 24 months, compared with singletons and twins. Triplets scored lower than singletons and twins on the Bayley Mental Developmental Index at 6, 12, and 24 months. A weight discordance of >15% was found for 15 triplet sets (65.2%). The discordant triplets showed decreased cognitive skills at 12 and 24 months, compared with their siblings, and received the lowest scores for maternal sensitivity. Hierarchical multivariate regression analysis revealed that greater medical risk at birth, multiple-birth status, lower maternal sensitivity, and reduced infant social involvement in the first 2 years were each predictive of lower cognitive outcomes at 2 years (R2 = 0.33). Triplets appear to be at higher risk for cognitive delays in the first 2 years of life, and discordant infants are at especially high risk. This delay is related in part to the difficulty of providing sensitive mothering to 3 infants at the same time. The findings may assist practitioners in guiding prenatal and postpartum parental care and management.

Unknown foundation determination for scour.

Science.gov (United States)

2012-04-01

Unknown foundations affect about 9,000 bridges in Texas. For bridges over rivers, this creates a problem : regarding scour decisions as the calculated scour depth cannot be compared to the foundation depth, and a : very conservative costly approach m...

The investigation and implementation of real-time face pose and direction estimation on mobile computing devices

Science.gov (United States)

Fu, Deqian; Gao, Lisheng; Jhang, Seong Tae

2012-04-01

The mobile computing device has many limitations, such as relative small user interface and slow computing speed. Usually, augmented reality requires face pose estimation can be used as a HCI and entertainment tool. As far as the realtime implementation of head pose estimation on relatively resource limited mobile platforms is concerned, it is required to face different constraints while leaving enough face pose estimation accuracy. The proposed face pose estimation method met this objective. Experimental results running on a testing Android mobile device delivered satisfactory performing results in the real-time and accurately.

Organizational conditions for dealing with the unknown unknown : illustrated by how a Dutch water management authority is preparing for climate change

NARCIS (Netherlands)

Termeer, C.J.A.M.; Brink, van den M.A.

2013-01-01

The central question of this article is the extent to which organizations, governmental authorities in particular, are able to deal with the unknown unknown. Drawing on Weick’s work on sensemaking, we introduce seven organizational conditions that can facilitate organizations to be reliable under

Wastewater use in urban agriculture: an exposure and risk ...

African Journals Online (AJOL)

Wastewater use in urban agriculture: an exposure and risk assessment in Accra, ... to pose the key risk to farmers due to hand-to mouth events (10 events/day). ... awareness of health risk, consumers did not prioritize health indicators when ...

Zebra Mussels Pose a Threat to Virginia's Waters

OpenAIRE

Helfrich, Louis A. (Louis Anthony), 1942-; Weigmann, Diana L.; Speenburgh, Renee M.; Neves, Richard J.; Kitchel, Lisie; Bruenderman, Sue A., 1962-

2005-01-01

Provides an brief introduction to the invasion of the zebra mussel into American waters, explains the economic consequences they pose, and discusses if Virginia will inherit the problem, what the public can do to help, the general lifecycle of the zebra mussel and if they can be controlled, and who is working on the zebra mussel problem.

Toxic-Metabolic Risk Factors in Pediatric Pancreatitis: Recommendations for Diagnosis, Management and Future Research

Science.gov (United States)

Husain, Sohail Z.; Morinville, Veronique; Pohl, John; Abu-El-Haija, Maisam; Bellin, Melena D.; Freedman, Steve; Hegyi, Peter; Heyman, Melvin B; Himes, Ryan; Ooi, Chee Y.; Schwarzenberg, Sarah Jane; Usatin, Danielle; Uc, Aliye

2016-01-01

Objectives Pancreatitis in children can result from metabolic and toxic risk factors, but the evidence linking these factors is sparse. We review the evidence for association or causality of these risk factors in pancreatitis, discuss management strategies and their rationale. Methods We conducted a review of the pediatric pancreatitis literature with respect to the following risk factors: (a) hyperlipidemia, (b) hypercalcemia, (c) chronic renal failure, (d) smoking exposure, (e) alcohol, and (f) medications. Areas of additional research were identified. Results Hypertriglyceridemia of 1000 mg/dl or greater poses an absolute risk for pancreatitis; persistent elevations of calcium are predisposing. Further research is necessary to determine whether end stage renal disease leads to increased pancreatitis in children similar to adults. It is unknown whether cigarette smoking exposure, which clearly increases risk in adults, also increases risk in children. The role of alcohol in pediatric pancreatitis, whether direct or modifying, needs to be elucidated. The evidence supporting most cases of medication-induced pancreatitis is poor. Drug structure, improper handling of drug by host, and by-stander status may be implicated. Other pancreatitis risk factors must be sought in all cases. Conclusions The quality of evidence supporting causative role of various toxic and metabolic factors in pediatric pancreatitis is variable. Careful phenotyping is essential, including search for other etiologic risk factors. Directed therapy includes correction/ removal of any agent identified, and general supportive measures. Further research is necessary to improve our understanding of these pancreatitis risk factors in children. PMID:26594832

Pose Self-Calibration of Stereo Vision Systems for Autonomous Vehicle Applications.

Science.gov (United States)

Musleh, Basam; Martín, David; Armingol, José María; de la Escalera, Arturo

2016-09-14

Nowadays, intelligent systems applied to vehicles have grown very rapidly; their goal is not only the improvement of safety, but also making autonomous driving possible. Many of these intelligent systems are based on making use of computer vision in order to know the environment and act accordingly. It is of great importance to be able to estimate the pose of the vision system because the measurement matching between the perception system (pixels) and the vehicle environment (meters) depends on the relative position between the perception system and the environment. A new method of camera pose estimation for stereo systems is presented in this paper, whose main contribution regarding the state of the art on the subject is the estimation of the pitch angle without being affected by the roll angle. The validation of the self-calibration method is accomplished by comparing it with relevant methods of camera pose estimation, where a synthetic sequence is used in order to measure the continuous error with a ground truth. This validation is enriched by the experimental results of the method in real traffic environments.

Pose Self-Calibration of Stereo Vision Systems for Autonomous Vehicle Applications

Science.gov (United States)

Musleh, Basam; Martín, David; Armingol, José María; de la Escalera, Arturo

2016-01-01

Nowadays, intelligent systems applied to vehicles have grown very rapidly; their goal is not only the improvement of safety, but also making autonomous driving possible. Many of these intelligent systems are based on making use of computer vision in order to know the environment and act accordingly. It is of great importance to be able to estimate the pose of the vision system because the measurement matching between the perception system (pixels) and the vehicle environment (meters) depends on the relative position between the perception system and the environment. A new method of camera pose estimation for stereo systems is presented in this paper, whose main contribution regarding the state of the art on the subject is the estimation of the pitch angle without being affected by the roll angle. The validation of the self-calibration method is accomplished by comparing it with relevant methods of camera pose estimation, where a synthetic sequence is used in order to measure the continuous error with a ground truth. This validation is enriched by the experimental results of the method in real traffic environments. PMID:27649178

“You’re dealing with an emotionally charged individual…”: an industry perspective on the challenges posed by medical tourists’ informal caregiver-companions

Science.gov (United States)

2013-01-01

Background Patients engage in medical tourism when they privately obtain a medical care abroad. Previous research shows that many medical tourists travel abroad with friends and family members who provide support and assistance. Meanwhile, very little is known about this important stakeholder group, referred to here as caregiver-companions. In this article we examine the challenges that can be posed by caregiver-companions and the overall practice of informal caregiving in medical tourism from an industry perspective. Specifically, we report on the findings of interviews conducted with international patient coordinators (IPCs) who work at destination facilities. IPCs come into regular contact with caregiver-companions in their professional positions and thus are ideally suited to comment on trends they have observed among this stakeholder group as well as the challenges they can pose to medical tourists, health workers, and facilities. Methods We conducted 20 semi-structured interviews with 21 IPCs from 16 different facilities across nine countries. Topics probed in the interviews included caregiver-companion roles, IPCs’ and others’ interaction with caregiver-companions, and potential health and safety risks posed to medical tourists and caregiver-companions. Thematic analysis of the verbatim transcripts was employed. Results Although most participants encouraged medical tourists to travel with a caregiver-companion, many challenges associated with caregiver-companions were identified. Three themes best characterize the challenges that emerged: (1) caregiver-companions require time, attention and resources; (2) caregiver-companions can disrupt the provision of quality care; and (3) caregiver-companions can be exposed to risks. IPCs pointed out that caregiver-companions may, for example, have a negative impact on the patient through cost of accompaniment or inadequate care provision. Caregiver-companions may also create unanticipated or extra work for IPCs, as

Short-Term Versus Long-Term Effects of Depressive Symptoms on Mortality in Patients on Dialysis

NARCIS (Netherlands)

van Dijk, Sandra; van den Beukel, Tessa O.; Dekker, Friedo W.; le Cessie, Saskia; Kaptein, Adrian A.; Honig, Adriaan; Siegert, Carl E.; Boeschoten, Elisabeth W.; Krediet, Ray T.; Verduijn, Marion; Apperloo, A. J.; Bijlsma, J. A.; Boekhout, M.; Boer, W. H.; van der Boog, B. J. M.; Büller, H. R.; van Buren, M.; de Charro, F. T.; Doorenbos, C. J.; van der Dorpel, M. A.; van Es, A.; Fagel, W. J.; Feith, G. W.; de Fijter, C. W. H.; Frenken, L. A. M.; Grave, W.; van Geelen, J. A. C. A.; Gerlag, P. G. G.; Gorgels, J. P. M. C.; Huisman, R. M.; Jager, K. J.; Jie, K.; Koning-Mulder, W. A. H.; Koolen, M. I.; Kremer Hovinga, T. K.; Lavrijssen, A. T. J.; Luik, A. J.; van der Meulen, J.; Parlevliet, K. J.; Raasveld, M. H. M.; van der Sande, F. M.; Schonck, M. J. M.; Schuurmans, M. M. J.; Siegert, C. E. H.; Stegeman, C. A.; Stevens, P.; Thijssen, J. G. P.; Valentijn, R. M.; Vastenburg, G. H.; Verburgh, C. A.

2012-01-01

Objective:. Depressive symptoms seem to pose a risk factor for mortality among patients on dialysis. It is currently unknown whether the association is only short-lived and whether associations over time depend on specific causes of mortality. Methods: In a prospective nationwide cohort study, 1528

IMU-based Real-time Pose Measurement system for Anterior Pelvic Plane in Total Hip Replacement Surgeries.

Science.gov (United States)

Zhe Cao; Shaojie Su; Hao Tang; Yixin Zhou; Zhihua Wang; Hong Chen

2017-07-01

With the aging of population, the number of Total Hip Replacement Surgeries (THR) increased year by year. In THR, inaccurate position of the implanted prosthesis may lead to the failure of the operation. In order to reduce the failure rate and acquire the real-time pose of Anterior Pelvic Plane (APP), we propose a measurement system in this paper. The measurement system includes two parts: Initial Pose Measurement Instrument (IPMI) and Real-time Pose Measurement Instrument (RPMI). IPMI is used to acquire the initial pose of the APP, and RPMI is used to estimate the real-time pose of the APP. Both are composed of an Inertial Measurement Unit (IMU) and magnetometer sensors. To estimate the attitude of the measurement system, the Extended Kalman Filter (EKF) is adopted in this paper. The real-time pose of the APP could be acquired together with the algorithm designed in the paper. The experiment results show that the Root Mean Square Error (RMSE) is within 1.6 degrees, which meets the requirement of THR operations.

Tridimensional pose estimation of a person head

International Nuclear Information System (INIS)

Perez Berenguer, Elisa; Soria, Carlos; Nasisi, Oscar; Mut, Vicente

2007-01-01

In this work, we present a method for estimating 3-D motion parameters; this method provides an alternative way for 3D head pose estimation from image sequence in the current computer vision literature. This method is robust over extended sequences and large head motions and accurately extracts the orientation angles of head from a single view. Experimental results show that this tracking system works well for development a human-computer interface for people that possess severe motor incapacity

Minimum Risk Pesticide: Definition and Product Confirmation

Science.gov (United States)

Minimum risk pesticides pose little to no risk to human health or the environment and therefore are not subject to regulation under FIFRA. EPA does not do any pre-market review for such products or labels, but violative products are subject to enforcement.

ESPRIT: Exercise Sensing and Pose Recovery Inference Tool, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — We propose to develop ESPRIT: an Exercise Sensing and Pose Recovery Inference Tool, in support of NASA's effort in developing crew exercise technologies for...

Pose tracking for augmented reality applications in outdoor archaeological sites

Science.gov (United States)

Younes, Georges; Asmar, Daniel; Elhajj, Imad; Al-Harithy, Howayda

2017-01-01

In recent years, agencies around the world have invested huge amounts of effort toward digitizing many aspects of the world's cultural heritage. Of particular importance is the digitization of outdoor archaeological sites. In the spirit of valorization of this digital information, many groups have developed virtual or augmented reality (AR) computer applications themed around a particular archaeological object. The problem of pose tracking in outdoor AR applications is addressed. Different positional systems are analyzed, resulting in the selection of a monocular camera-based user tracker. The limitations that challenge this technique from map generation, scale, anchoring, to lighting conditions are analyzed and systematically addressed. Finally, as a case study, our pose tracking system is implemented within an AR experience in the Byblos Roman theater in Lebanon.

Amphibians at risk? Susceptibility of terrestrial amphibian life stages to pesticides.

Science.gov (United States)

Brühl, Carsten A; Pieper, Silvia; Weber, Brigitte

2011-11-01

Current pesticide risk assessment does not specifically consider amphibians. Amphibians in the aquatic environment (aquatic life stages or postmetamorphic aquatic amphibians) and terrestrial living juvenile or adult amphibians are assumed to be covered by the risk assessment for aquatic invertebrates and fish, or mammals and birds, respectively. This procedure has been evaluated as being sufficiently protective regarding the acute risk posed by a number of pesticides to aquatic amphibian life stages (eggs, larvae). However, it is unknown whether the exposure and sensitivity of terrestrial living amphibians are comparable to mammalian and avian exposure and sensitivity. We reviewed the literature on dermal pesticide absorption and toxicity studies for terrestrial life stages of amphibians, focusing on the dermal exposure pathway, that is, through treated soil or direct overspray. In vitro studies demonstrated that cutaneous absorption of chemicals is significant and that chemical percutaneous passage, P (cm/h), is higher in amphibians than in mammals. In vivo, the rapid and substantial uptake of the herbicide atrazine from treated soil by toads (Bufo americanus) has been described. Severe toxic effects on various amphibian species have been reported for field-relevant application rates of different pesticides. In general, exposure and toxicity studies for terrestrial amphibian life stages are scarce, and the reported data indicate the need for further research, especially in light of the global amphibian decline. Copyright © 2011 SETAC.

Stochastic fuzzy environmental risk characterization of uncertainty and variability in risk assessments: A case study of polycyclic aromatic hydrocarbons in soil at a petroleum-contaminated site in China

International Nuclear Information System (INIS)

Hu, Yan; Wang, Zesen; Wen, Jingya; Li, Yu

2016-01-01

Highlights: • Deal with environmental quality guidelines absence in risk characterization. • Quantitative represention of uncertainty from environmental quality guidelines. • Quantitative represention of variability from contaminant exposure concentrations. • Establishment of stochastic-fuzzy environmental risk characterization approach framework. - Abstract: Better decisions are made using risk assessment models when uncertainty and variability are explicitly acknowledged. Uncertainty caused by a lack of uniform and scientifically supported environmental quality guidelines and variability in the degree of exposure of environmental systems to contaminants are here incorporated in a stochastic fuzzy environmental risk characterization (SFERC) approach. The approach is based on quotient probability distribution and environmental risk level fuzzy membership function methods. The SFERC framework was used to characterize the environmental risks posed by 16 priority polycyclic aromatic hydrocarbons (PAHs) in soil at a typical petroleum-contaminated site in China. This relied on integrating data from the literature and field and laboratory experiments. The environmental risk levels posed by the PAHs under four risk scenarios were determined using the SFERC approach, using “residential land” and “industrial land” environmental quality guidelines under “loose” and “strict” strictness parameters. The results showed that environmental risks posed by PAHs in soil are primarily caused by oil exploitation, traffic emissions, and coal combustion. The SFERC approach is an effective tool for characterizing uncertainty and variability in environmental risk assessments and for managing contaminated sites.

Stochastic fuzzy environmental risk characterization of uncertainty and variability in risk assessments: A case study of polycyclic aromatic hydrocarbons in soil at a petroleum-contaminated site in China

Energy Technology Data Exchange (ETDEWEB)

Hu, Yan [MOE Key Laboratory of Regional Energy Systems Optimization, Resources and Environmental Research Academy, North China Electric Power University, Beijing 102206 (China); State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environment Sciences, Beijing 100012 (China); Wang, Zesen [MOE Key Laboratory of Regional Energy Systems Optimization, Resources and Environmental Research Academy, North China Electric Power University, Beijing 102206 (China); Wen, Jingya [MOE Key Laboratory of Regional Energy Systems Optimization, Resources and Environmental Research Academy, North China Electric Power University, Beijing 102206 (China); Institute of Hydropower and Environment Research, Beijing 100012 (China); Li, Yu, E-mail: liyuxx8@hotmail.com [MOE Key Laboratory of Regional Energy Systems Optimization, Resources and Environmental Research Academy, North China Electric Power University, Beijing 102206 (China)

2016-10-05

Highlights: • Deal with environmental quality guidelines absence in risk characterization. • Quantitative represention of uncertainty from environmental quality guidelines. • Quantitative represention of variability from contaminant exposure concentrations. • Establishment of stochastic-fuzzy environmental risk characterization approach framework. - Abstract: Better decisions are made using risk assessment models when uncertainty and variability are explicitly acknowledged. Uncertainty caused by a lack of uniform and scientifically supported environmental quality guidelines and variability in the degree of exposure of environmental systems to contaminants are here incorporated in a stochastic fuzzy environmental risk characterization (SFERC) approach. The approach is based on quotient probability distribution and environmental risk level fuzzy membership function methods. The SFERC framework was used to characterize the environmental risks posed by 16 priority polycyclic aromatic hydrocarbons (PAHs) in soil at a typical petroleum-contaminated site in China. This relied on integrating data from the literature and field and laboratory experiments. The environmental risk levels posed by the PAHs under four risk scenarios were determined using the SFERC approach, using “residential land” and “industrial land” environmental quality guidelines under “loose” and “strict” strictness parameters. The results showed that environmental risks posed by PAHs in soil are primarily caused by oil exploitation, traffic emissions, and coal combustion. The SFERC approach is an effective tool for characterizing uncertainty and variability in environmental risk assessments and for managing contaminated sites.

Deformation-specific and deformation-invariant visual object recognition: pose vs identity recognition of people and deforming objects

Directory of Open Access Journals (Sweden)

Tristan J Webb

2014-04-01

Full Text Available When we see a human sitting down, standing up, or walking, we can recognise one of these poses independently of the individual, or we can recognise the individual person, independently of the pose. The same issues arise for deforming objects. For example, if we see a flag deformed by the wind, either blowing out or hanging languidly, we can usually recognise the flag, independently of its deformation; or we can recognise the deformation independently of the identity of the flag. We hypothesize that these types of recognition can be implemented by the primate visual system using temporo-spatial continuity as objects transform as a learning principle. In particular, we hypothesize that pose or deformation can be learned under conditions in which large numbers of different people are successively seen in the same pose, or objects in the same deformation. We also hypothesize that person-specific representations that are independent of pose, and object-specific representations that are independent of deformation and view, could be built, when individual people or objects are observed successively transforming from one pose or deformation and view to another. These hypotheses were tested in a simulation of the ventral visual system, VisNet, that uses temporal continuity, implemented in a synaptic learning rule with a short-term memory trace of previous neuronal activity, to learn invariant representations. It was found that depending on the statistics of the visual input, either pose-specific or deformation-specific representations could be built that were invariant with respect to individual and view; or that identity-specific representations could be built that were invariant with respect to pose or deformation and view. We propose that this is how pose-specific and pose-invariant, and deformation-specific and deformation-invariant, perceptual representations are built in the brain.

Muscle utilization patterns vary by skill levels of the practitioners across specific yoga poses (asanas).

Science.gov (United States)

Ni, Meng; Mooney, Kiersten; Balachandran, Anoop; Richards, Luca; Harriell, Kysha; Signorile, Joseph F

2014-08-01

To compare muscle activation patterns in 14 dominant side muscles during different yoga poses across three skill levels. Mixed repeated-measures descriptive study. University neuromuscular research laboratory, Miami, US. A group of 36 yoga practitioners (9 M/27 F; mean ± SD, 31.6 ± 12.6 years) with at least 3 months yoga practice experience. Each of the 11 surya namaskar poses A and B was performed separately for 15s and the surface electromyography for 14 muscles were recorded. Normalized root mean square of the electromyographic signal (NrmsEMG) for 14 muscles (5 upper body, 4 trunk, 5 lower body). There were significant main effects of pose for all fourteen muscles except middle trapezius (p<.02) and of skill level for the vastus medialis; p=.027). A significant skill level × pose interaction existed for five muscles (pectoralis major sternal head, anterior deltoid, medial deltoid, upper rectus abdominis and gastrocnemius lateralis; p<.05). Post hoc analyses using Bonferroni comparisons indicated that different poses activated specific muscle groups; however, this varied by skill level. Our results indicate that different poses can produce specific muscle activation patterns which may vary due to practitioners' skill levels. This information can be used in designing rehabilitation and training programs and for cuing during yoga training. Copyright © 2014 Elsevier Ltd. All rights reserved.

Haloacetic acids in the aquatic environment. Part II: ecological risk assessment

International Nuclear Information System (INIS)

Hanson, Mark L.; Solomon, Keith R.

2004-01-01

Haloacetic acids (HAAs) are environmental contaminants found in aquatic ecosystems throughout the world as a result of both anthropogenic and natural production. The ecological risk posed by these compounds to organisms in freshwater environments, with a specific focus on aquatic macrophytes, was characterized. The plants evaluated were Lemna gibba, Myriophyllum spicatum and M. sibiricum and the HAAs screened were monochloroacetic acid (MCA), dichloroacetic acid (DCA), trichloroacetic acid (TCA), trifluoroacetic acid (TFA) and chlorodifluoroacetic acid (CDFA). Laboratory toxicity data formed the basis of the risk assessment, but field studies were also utilized. The estimated risk was calculated using hazard quotients (HQ), as well as effect measure distributions (EMD) in a modified probabilistic ecological risk assessment. EMDs were used to estimate HAA thresholds of toxicity for use in HQ assessments. This threshold was found to be a more sensitive measure of low toxicity than the no observed effect concentrations (NOEC) or the effective concentration (EC 10 ). Using both deterministic and probabilistic methods, it was found that HAAs do not pose a significant risk to freshwater macrophytes at current environmental concentrations in Canada, Europe or Africa for both single compound and mixture exposures. Still, HAAs are generally found as mixtures and their potential interactions are not fully understood, rendering this phase of the assessment uncertain and justifying further effects characterization. TCA in some environments poses a slight risk to phytoplankton and future concentrations of TFA and CDFA are likely to increase due to their recalcitrant nature, warranting continued environmental surveillance of HAAs. - Current environmental concentrations of haloacetic acids do not pose a risk to aquatic macrophytes, but could impact plankton

A new benchmark for pose estimation with ground truth from virtual reality

DEFF Research Database (Denmark)

Schlette, Christian; Buch, Anders Glent; Aksoy, Eren Erdal

2014-01-01

The development of programming paradigms for industrial assembly currently gets fresh impetus from approaches in human demonstration and programming-by-demonstration. Major low- and mid-level prerequisites for machine vision and learning in these intelligent robotic applications are pose estimation......, stereo reconstruction and action recognition. As a basis for the machine vision and learning involved, pose estimation is used for deriving object positions and orientations and thus target frames for robot execution. Our contribution introduces and applies a novel benchmark for typical multi...

A framework to estimate concentrations of potentially unknown substances by semi-quantification in liquid chromatography electrospray ionization mass spectrometry

DEFF Research Database (Denmark)

Pieke, Eelco Nicolaas; Granby, Kit; Trier, Xenia

2017-01-01

Risk assessment of exposure to chemicals from food and other sources rely on quantitative information of the occurrence of these chemicals. As screening analysis is increasingly used, a strategy to semi-quantify unknown or untargeted analytes is required. A proof of concept strategy to semi-quant...

Synthetic risks, risk potency, and carcinogen regulation.

Science.gov (United States)

Viscusi, W K; Hakes, J K

1998-01-01

This article analyzes a comprehensive sample of over 350 chemicals tested for carcinogenicity to assess the determinants of the probability of regulation. Controlling for differences in the risk potency and noncancer risks, synthetic chemicals have a significantly higher probability of regulation overall: this is due to the greater likelihood of U.S. Food and Drug Administration (FDA) regulation. Measures of risk potency increase the probability of regulation by the U.S. Environmental Protection Agency (EPA), have a somewhat weaker positive effect on regulation by the U.S. Occupational Safety and Health Administration (OSHA), and decrease the likelihood of regulation by the FDA. The overall regulatory pattern is one in which the FDA targets synthetic chemicals and chemicals that pose relatively minor cancer risk. The EPA particularly performed more sensibly than many critics have suggested.

Structural interface parameters are discriminatory in recognising near-native poses of protein-protein interactions.

Directory of Open Access Journals (Sweden)

Sony Malhotra

Full Text Available Interactions at the molecular level in the cellular environment play a very crucial role in maintaining the physiological functioning of the cell. These molecular interactions exist at varied levels viz. protein-protein interactions, protein-nucleic acid interactions or protein-small molecules interactions. Presently in the field, these interactions and their mechanisms mark intensively studied areas. Molecular interactions can also be studied computationally using the approach named as Molecular Docking. Molecular docking employs search algorithms to predict the possible conformations for interacting partners and then calculates interaction energies. However, docking proposes number of solutions as different docked poses and hence offers a serious challenge to identify the native (or near native structures from the pool of these docked poses. Here, we propose a rigorous scoring scheme called DockScore which can be used to rank the docked poses and identify the best docked pose out of many as proposed by docking algorithm employed. The scoring identifies the optimal interactions between the two protein partners utilising various features of the putative interface like area, short contacts, conservation, spatial clustering and the presence of positively charged and hydrophobic residues. DockScore was first trained on a set of 30 protein-protein complexes to determine the weights for different parameters. Subsequently, we tested the scoring scheme on 30 different protein-protein complexes and native or near-native structure were assigned the top rank from a pool of docked poses in 26 of the tested cases. We tested the ability of DockScore to discriminate likely dimer interactions that differ substantially within a homologous family and also demonstrate that DOCKSCORE can distinguish correct pose for all 10 recent CAPRI targets.

Pose Self-Calibration of Stereo Vision Systems for Autonomous Vehicle Applications

Directory of Open Access Journals (Sweden)

Basam Musleh

2016-09-01

Full Text Available Nowadays, intelligent systems applied to vehicles have grown very rapidly; their goal is not only the improvement of safety, but also making autonomous driving possible. Many of these intelligent systems are based on making use of computer vision in order to know the environment and act accordingly. It is of great importance to be able to estimate the pose of the vision system because the measurement matching between the perception system (pixels and the vehicle environment (meters depends on the relative position between the perception system and the environment. A new method of camera pose estimation for stereo systems is presented in this paper, whose main contribution regarding the state of the art on the subject is the estimation of the pitch angle without being affected by the roll angle. The validation of the self-calibration method is accomplished by comparing it with relevant methods of camera pose estimation, where a synthetic sequence is used in order to measure the continuous error with a ground truth. This validation is enriched by the experimental results of the method in real traffic environments.

Personal privacy, information assurance, and the threat posed by malware techology

Science.gov (United States)

Stytz, Martin R.; Banks, Sheila B.

2006-04-01

In spite of our best efforts to secure the cyber world, the threats posed to personal privacy by attacks upon networks and software continue unabated. While there are many reasons for this state of affairs, clearly one of the reasons for continued vulnerabilities in software is the inability to assess their security properties and test their security systems while they are in development. A second reason for this growing threat to personal privacy is the growing sophistication and maliciousness of malware coupled with the increasing difficulty of detecting malware. The pervasive threat posed by malware coupled with the difficulties faced when trying to detect its presence or an attempted intrusion make addressing the malware threat one of the most pressing issues that must be solved in order to insure personal privacy to users of the internet. In this paper, we will discuss the threat posed by malware, the types of malware found in the wild (outside of computer laboratories), and current techniques that are available for from a successful malware penetration. The paper includes a discussion of anti-malware tools and suggestions for future anti-malware efforts.

Hierarchical graphical-based human pose estimation via local multi-resolution convolutional neural network

Science.gov (United States)

Zhu, Aichun; Wang, Tian; Snoussi, Hichem

2018-03-01

This paper addresses the problems of the graphical-based human pose estimation in still images, including the diversity of appearances and confounding background clutter. We present a new architecture for estimating human pose using a Convolutional Neural Network (CNN). Firstly, a Relative Mixture Deformable Model (RMDM) is defined by each pair of connected parts to compute the relative spatial information in the graphical model. Secondly, a Local Multi-Resolution Convolutional Neural Network (LMR-CNN) is proposed to train and learn the multi-scale representation of each body parts by combining different levels of part context. Thirdly, a LMR-CNN based hierarchical model is defined to explore the context information of limb parts. Finally, the experimental results demonstrate the effectiveness of the proposed deep learning approach for human pose estimation.

Hierarchical graphical-based human pose estimation via local multi-resolution convolutional neural network

Directory of Open Access Journals (Sweden)

Aichun Zhu

2018-03-01

Full Text Available This paper addresses the problems of the graphical-based human pose estimation in still images, including the diversity of appearances and confounding background clutter. We present a new architecture for estimating human pose using a Convolutional Neural Network (CNN. Firstly, a Relative Mixture Deformable Model (RMDM is defined by each pair of connected parts to compute the relative spatial information in the graphical model. Secondly, a Local Multi-Resolution Convolutional Neural Network (LMR-CNN is proposed to train and learn the multi-scale representation of each body parts by combining different levels of part context. Thirdly, a LMR-CNN based hierarchical model is defined to explore the context information of limb parts. Finally, the experimental results demonstrate the effectiveness of the proposed deep learning approach for human pose estimation.

Introduced organisms pose the most significant threat to the ...

African Journals Online (AJOL)

spamer

Introduced organisms pose the most significant threat to the conservation status of oceanic islands (e.g.. Williamson 1996). Subantarctic Prince Edward Island, the smaller of the two islands in the Prince Edward. Island group, has few introduced organisms; it is cur- rently known to support only three introduced animals.

Morozov-type discrepancy principle for nonlinear ill-posed problems ...

Indian Academy of Sciences (India)

For proving the existence of a regularization parameter under a Morozov-type discrepancy principle for Tikhonov regularization of nonlinear ill-posed problems, it is required to impose additional nonlinearity assumptions on the forward operator. Lipschitz continuity of the Freéchet derivative and requirement of the Lipschitz ...

Full Body Pose Estimation During Occlusion using Multiple Cameras

DEFF Research Database (Denmark)

Fihl, Preben; Cosar, Serhan

people is a very challenging problem for methods based on pictorials structure as for any other monocular pose estimation method. In this report we present work on a multi-view approach based on pictorial structures that integrate low level information from multiple calibrated cameras to improve the 2D...

Morozov-type discrepancy principle for nonlinear ill-posed problems ...

Indian Academy of Sciences (India)

2016-08-26

Aug 26, 2016 ... For proving the existence of a regularization parameter under a Morozov-type discrepancy principle for Tikhonov regularization of nonlinear ill-posed problems, it is required to impose additional nonlinearity assumptions on the forward operator. Lipschitz continuity of the Freéchet derivative and requirement ...

Managing the Unknown

DEFF Research Database (Denmark)

Wieland, Andreas

2016-01-01

Early approaches to managing risk in supply chains were based on enterprise risk management tools – tools that had been developed for a system called the “company.” These tools often contained risk categories relating to operational and financial circumstances within the company. Moreover......, these tools were easily scalable, as they allowed the inclusion of additional risk categories. It comes as no surprise, therefore, that the notion of risks further upstream and downstream in the supply chain has led risk managers to include new categories such as “supplier insolvency,” “supplier quality......” or “defects of supplied parts (per million).” The inclusion of such categories that represent risk sources outside of their own companies has certainly been a great achievement. But, as I will argue, this is not enough to shift from a company view towards a supply chain view that has been shown to enable...

The English and northern (Sweden and Norway) systems regarding the questions posed by the white book; Les systemes anglais et nordiques (Suede et Norvege) au regard des questions posees dans le livre blanc

Energy Technology Data Exchange (ETDEWEB)

Secretariat d' Etat a l' Industrie [ed.] [Secretariat d' Etat a l' Industrie, Ministere de l' Economie, des Finances et de l' Industrie, Paris (France)

1999-06-15

annually a report on market progress. In liberalized systems still two more features are worth to mention, the appearance of actors unknown in centralized systems (as the suppliers, for instance) and the high 'volatility' of the electricity prices that presses both manufacturers and customers to protect themselves against the market's risks. The second part of the report is devoted to the questions raised in the White Book, namely, service's quality, economic efficiency, service continuity, etc. In conclusion, the French conception of Public Service has not an exact analogue but most of its objectives are assigned actually to the Network Authority, the main task of which is promotion of economic efficiency. The networks either privatized, as in United Kingdom, or still public, as in Norway or Swede, are closely controlled by the Network Authority. This is done via price structure establishment and by imposing an upper level on the revenue of the network operators. In UK the action of the Network Authority was highly instrumental in growth of productivity in the monopolistic sectors of electric industry, i.e., transport and distribution. Norway and Swede are in retard from this point of view. The main beneficiaries of the market liberalization were the industries while the profit of domestic customers is still incipient. In the northern countries in spite of early access to competition the profit was so far low. In its second part the document APIS of the Council for Industrial Policy poses questions and presents ways of approach in UK and northern countries relating to: - The directive and its range; - Reinforcing the Public Service; - Revamping the Electric System to support growth; Preserving the networks for overall profit; - Defining of Public Establishment EDF within the new organization; - Developing an efficient network. Ways of approach in UK and northern countries regulation are presented.

Feature-based fast grasping for unknown objects

NARCIS (Netherlands)

Lei, Q.

2018-01-01

According to the report by the United Nations in 2015, the global population of older persons aged 60 years or over is predicted to grow to 1.4 billion by 2030. A rapidly aging population poses a challenging problem for human beings, i.e. supply shortage of working-age people. To solve this problem,

Zoonotic pathogens from feral swine that pose a significant threat to public health.

Science.gov (United States)

Brown, V R; Bowen, R A; Bosco-Lauth, A M

2018-06-01

The natural fecundity of suids, great ability to adapt to new habitats and desire for local hunting opportunities leading to translocation of feral pigs to regions where they are not yet established have all been instrumental in the home range expansion of feral swine. Feral swine populations in the United States continue to expand, wreaking havoc on agricultural lands, further compromising threatened and endangered species, and posing a microbiological threat to humans, domestic livestock and companion animals. This manuscript thoroughly reviews zoonotic diseases of concern including brucellosis, bovine tuberculosis, leptospirosis, enteric pathogens, both Salmonella spp. and shiga toxin-producing Escherichia coli, and hepatitis E. These pathogens are not a comprehensive list of microbes that are capable of infecting both humans and feral swine, but rather have been selected as they are known to infect US feral swine, direct transmission between wild suids and humans has previously been documented, or they have been shown to be readily transmitted during processing or consumption of feral swine pork. Humans that interact directly or indirectly with feral swine are at much higher risk for the development of a number of zoonotic pathogens. Numerous case reports document transmission events from feral swine and wild boar to humans, and the resulting diseases may be mild and self-limiting, chronic or fatal. Individuals that interact with feral swine should take preventative measures to minimize the risk of disease transmission and all meat should be thoroughly cooked. Additionally, public health campaigns to increase knowledge of the risks associated with feral swine are imperative. © 2018 Blackwell Verlag GmbH.

Multifactor Analysis of Roadheader’s Body Pose Responses during the Horizontal Cutting Process

Directory of Open Access Journals (Sweden)

Kai Zong

2018-01-01

Full Text Available Based on the Lagrange equation in system dynamics, aiming at the horizontal cutting process, the dynamical coupling model of boom-type roadheader’s body pose was established. According to input problem of solving the model, a calculation method of the cutting head load was proposed, and the relationship between the cutting head load and pressure of the driving cylinders and swing angle of the cutting arm was obtained through simulating analysis. The simulation model was established to solve the dynamical coupling model. The cutting head load, horizontal swing angle of the cutting arm, and dip angle of coal seam were regarded as independent variables to perform changing parameter analysis in variations of the body pose. The field experiment was carried out, and the measured data is basically consistent with the simulation values. The results show that lateral displacement of the body can reach up to 6.5 cm, backward displacement can reach up to 5.2 cm, floor-based quantity can reach up to 11 cm, pitch angle of the body can reach up to 7.8°, and roll angle can reach up to 2.1°. Variations of the body pose parameters are influenced greatly by the cutting head load, while the influence from horizontal swing angle of the cutting arm and dip angle of coal seam is slighter. Among the pose parameters, floor-based quantity and pitch angle of the body vary relatively greatly, which tend to seriously influence forming quality of the roadway and should be mainly considered in deviation rectification of the roadheader’s body pose.

Low Risk Anomalies?

DEFF Research Database (Denmark)

Schneider, Paul; Wagner, Christian; Zechner, Josef

This paper shows theoretically and empirically that beta- and volatility-based low risk anomalies are driven by return skewness. The empirical patterns concisely match the predictions of our model that endogenizes the role of skewness for stock returns through default risk. With increasing downside...... risk, the standard capital asset pricing model (CAPM) increasingly overestimates expected equity returns relative to firms' true (skew-adjusted) market risk. Empirically, the profitability of betting against beta/volatility increases with firms' downside risk, and the risk-adjusted return differential...... of betting against beta/volatility among low skew firms compared to high skew firms is economically large. Our results suggest that the returns to betting against beta or volatility do not necessarily pose asset pricing puzzles but rather that such strategies collect premia that compensate for skew risk...

Methodology for the assessment of human health risks associated ...

African Journals Online (AJOL)

Studies have shown that the aquatic environment can be polluted by contaminates that are accumulated by freshwater fish and this may pose a health risk to the ... bioaccumulation potential and health risks of analytes, sound sampling design, risk assessment procedures and performing monitoring at different scales and ...

Environmental risk assessment of pesticides in Ethiopia

NARCIS (Netherlands)

Teklu, B.M.

2016-01-01

The current increase in application rate and usage frequency of application of pesticides in Ethiopia pose direct risks to surface water aquatic organisms and humans and cattle using surface water as a source of drinking water in rural parts of the country. A model based risk assessment as

Feature and Pose Constrained Visual Aided Inertial Navigation for Computationally Constrained Aerial Vehicles

Science.gov (United States)

Williams, Brian; Hudson, Nicolas; Tweddle, Brent; Brockers, Roland; Matthies, Larry

2011-01-01

A Feature and Pose Constrained Extended Kalman Filter (FPC-EKF) is developed for highly dynamic computationally constrained micro aerial vehicles. Vehicle localization is achieved using only a low performance inertial measurement unit and a single camera. The FPC-EKF framework augments the vehicle's state with both previous vehicle poses and critical environmental features, including vertical edges. This filter framework efficiently incorporates measurements from hundreds of opportunistic visual features to constrain the motion estimate, while allowing navigating and sustained tracking with respect to a few persistent features. In addition, vertical features in the environment are opportunistically used to provide global attitude references. Accurate pose estimation is demonstrated on a sequence including fast traversing, where visual features enter and exit the field-of-view quickly, as well as hover and ingress maneuvers where drift free navigation is achieved with respect to the environment.

Classification of Unknown Thermocouple Types Using Similarity Factor Measurement

Directory of Open Access Journals (Sweden)

Seshu K. DAMARLA

2011-01-01

Full Text Available In contrast to classification using PCA method, a new methodology is proposed for type identification of unknown thermocouple. The new methodology is based on calculating the degree of similarity between two multivariate datasets using two types of similarity factors. One similarity factor is based on principle component analysis and the angles between the principle component subspaces while the other is based on the Mahalanobis distance between the datasets. Datasets containing thermo-emfs against given temperature ranges are formed for each type of thermocouple (e.g. J, K, S, T, R, E, B and N type by experimentation are considered as reference datasets. Datasets corresponding to unknown type are captured. Similarity factor between the datasets one of which being the unknown type and the other being each known type are compared. When maximum similarity factor occurs, then the class of unknown type is allocated to that of known type.

POSING THE HISTORICAL JESUS QUESTION AND THE GOAL OF ...

African Journals Online (AJOL)

mycl

... study recommended that. African scholars be allowed to develop and pose the Historical Jesus ... he is seen as the starting point for modern critical study of Jesus. (Burer). ... African anthropology and culture and the data of revelation, and how this theology ... Man” from two perspectives: that of a biblical culture in the first.

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

Science.gov (United States)

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

2014-01-01

Rock falls are common in Yosemite Valley, California, posing substantial hazard and risk to the approximately four million annual visitors to Yosemite National Park. Rock falls in Yosemite Valley over the past few decades have damaged structures and caused injuries within developed regions located on or adjacent to talus slopes highlighting the need for additional investigations into rock-fall hazard and risk. This assessment builds upon previous investigations of rock-fall hazard and risk in Yosemite Valley and focuses on hazard and risk to structures posed by relatively frequent fragmental-type rock falls as large as approximately 100,000 (cubic meters) in volume.

Socioeconomic status in HCV infected patients – risk and prognosis

DEFF Research Database (Denmark)

Omland, Lars Haukali; Osler, Merete; Jepsen, Peter

2013-01-01

It is unknown whether socioeconomic status (SES) is a risk factor for hepatitis C virus (HCV) infection or a prognostic factor following infection.......It is unknown whether socioeconomic status (SES) is a risk factor for hepatitis C virus (HCV) infection or a prognostic factor following infection....

The Pesticide Risk Beliefs Inventory: A Quantitative Instrument for the Assessment of Beliefs about Pesticide Risks

OpenAIRE

LePrevost, Catherine E.; Blanchard, Margaret R.; Cope, W. Gregory

2011-01-01

Recent media attention has focused on the risks that agricultural pesticides pose to the environment and human health; thus, these topics provide focal areas for scientists and science educators to enhance public understanding of basic toxicology concepts. This study details the development of a quantitative inventory to gauge pesticide risk beliefs. The goal of the inventory was to characterize misconceptions and knowledge gaps, as well as expert-like beliefs, concerning pesticide risk. This...

Quantifying the risk of spread of bovine viral diarrhoea virus (BVDV) between contiguous herds in Ireland.

Science.gov (United States)

Graham, D A; Clegg, T A; Thulke, H-H; O'Sullivan, P; McGrath, G; More, S J

2016-04-01

The control of bovine viral diarrhoea virus (BVDV) mainly focuses on the identification and restriction of persistently infected (PI) animals. However, other transmission pathways can also result in new breakdowns, including the movement of animals pregnant with PI calves (Trojan animals) and the spread of infection between contiguous farms. Contiguous spread is likely an important problem in the BVD eradication programme in Ireland, given the spatial distribution of residual infection, and the highly fragmented nature of land holdings on many Irish farms. In this study, we seek to quantify the risk of BVD spread between contiguous herds in Ireland. Multivariable logistic models were used to estimate the risk of a herd having BVD positive calves in January to June 2014 (the study period) when contiguous to a herd that had at least one BVD positive calf born in 2013. The models included risk factors relating to the study herd and to neighbouring herds. Separate multivariable models were built for each of four "PI-neighbour" factors relating to the presence of BVD+ animals and/or the presence of offspring of PI breeding animals. In total, 58,483 study herds were enrolled. The final model contained the province, the log of the number of calf births born during the study period, the number of cattle purchased between January 2013 and January 2014, and with a two-way interaction between the number of animals of unknown BVD status in the study herd and the PI-neighbour risk factor. When the number of PI-neighbour herds was used as the PI-neighbour risk factor, the odds ratio (OR) associated with the number of PI-neighbour herds ranged from 1.07 to 3.02, depending on the number of unknown animals present. To further explore the risk associated with PI-neighbour factors, the models were repeated using a subset of the study herds (n=7440) that contained no animals of unknown status. The best fitting model including "any PI-neighbour" as the PI-neighbour factor and also

Improving head and body pose estimation through semi-supervised manifold alignment

KAUST Repository

Heili, Alexandre

2014-10-27

In this paper, we explore the use of a semi-supervised manifold alignment method for domain adaptation in the context of human body and head pose estimation in videos. We build upon an existing state-of-the-art system that leverages on external labelled datasets for the body and head features, and on the unlabelled test data with weak velocity labels to do a coupled estimation of the body and head pose. While this previous approach showed promising results, the learning of the underlying manifold structure of the features in the train and target data and the need to align them were not explored despite the fact that the pose features between two datasets may vary according to the scene, e.g. due to different camera point of view or perspective. In this paper, we propose to use a semi-supervised manifold alignment method to bring the train and target samples closer within the resulting embedded space. To this end, we consider an adaptation set from the target data and rely on (weak) labels, given for example by the velocity direction whenever they are reliable. These labels, along with the training labels are used to bias the manifold distance within each manifold and to establish correspondences for alignment.

Gaussian particle filter based pose and motion estimation

Institute of Scientific and Technical Information of China (English)

无

2007-01-01

Determination of relative three-dimensional (3D) position, orientation, and relative motion between two reference frames is an important problem in robotic guidance, manipulation, and assembly as well as in other fields such as photogrammetry.A solution to pose and motion estimation problem that uses two-dimensional (2D) intensity images from a single camera is desirable for real-time applications. The difficulty in performing this measurement is that the process of projecting 3D object features to 2D images is a nonlinear transformation. In this paper, the 3D transformation is modeled as a nonlinear stochastic system with the state estimation providing six degrees-of-freedom motion and position values, using line features in image plane as measuring inputs and dual quaternion to represent both rotation and translation in a unified notation. A filtering method called the Gaussian particle filter (GPF) based on the particle filtering concept is presented for 3D pose and motion estimation of a moving target from monocular image sequences. The method has been implemented with simulated data, and simulation results are provided along with comparisons to the extended Kalman filter (EKF) and the unscented Kalman filter (UKF) to show the relative advantages of the GPF. Simulation results showed that GPF is a superior alternative to EKF and UKF.

Migrants at/as risk : Identity verification and risk assessment technologies in the Netherlands

NARCIS (Netherlands)

La Fors, Karolina; Van der Ploeg, Irma; Van der Ploeg, Irma; Pridmore, Jason

2015-01-01

International policy discourse on migration and practices geared toward the sorting out of entitlements for migrants to enter and reside in a country mobilize a discourse that increasingly frames them as posing risks to the societies of their host countries (Leers, 2012; Leers, 2011),

Morozov-type discrepancy principle for nonlinear ill-posed problems ...

Indian Academy of Sciences (India)

[3] Engl H W, Kunisch K and Neubauer A, Convergence rates for Tikhonov regularization of nonliner problems, Inverse Problems 5 (1989) 523–540. [4] Hanke M, Neubauer A and Scherzer O, A convergence analysis of Landweber iteration for nonlinear ill-posed problems, Numer. Math. 72 (1995) 21–37. [5] Hofmann B and ...

Enhancing Students' Communication Skills through Problem Posing and Presentation

Science.gov (United States)

Sugito; E. S., Sri Mulyani; Hartono; Supartono

2017-01-01

This study was to explore how enhance communication skill through problem posing and presentation method. The subjects of this research were the seven grade students Junior High School, including 20 male and 14 female. This research was conducted in two cycles and each cycle consisted of four steps, they were: planning, action, observation, and…

Chemical Mixtures Health Risk Assessment of Environmental Contaminants: Concepts, Methods, Applications

Science.gov (United States)

This problems-based, introductory workshop focuses on methods to assess health risks posed by exposures to chemical mixtures in the environment. Chemical mixtures health risk assessment methods continue to be developed and evolve to address concerns over health risks from multic...

3D Facial Landmarking under Expression, Pose, and Occlusion Variations

NARCIS (Netherlands)

H. Dibeklioğ lu; A.A. Salah (Albert Ali); L. Akarun

2008-01-01

htmlabstractAutomatic localization of 3D facial features is important for face recognition, tracking, modeling and expression analysis. Methods developed for 2D images were shown to have problems working across databases acquired with different illumination conditions. Expression variations, pose

Granular Materials and the Risks They Pose for Success on the Moon and Mars

Science.gov (United States)

Wilkinson, R. Allen; Behringer, Robert P.; Jenkins, James T.; Louge, Michel Y.

2005-02-01

Working with soil, sand, powders, ores, cement and sintered bricks, excavating, grading construction sites, driving off-road, transporting granules in chutes and pipes, sifting gravel, separating solids from gases, and using hoppers are so routine that it seems straightforward to do it on the Moon and Mars as we do it on Earth. This paper brings to the fore how little these processes are understood and the millennia-long trial-and-error practices that lead to today's massive over-design, high failure rate, and extensive incremental scaling up of industrial processes because of the inadequate predictive tools for design. We present a number of pragmatic scenarios where granular materials play a role, the risks involved, and what understanding is needed to greatly reduce the risks.

Did Buddha turn the other cheek too? A comparison of posing biases between Jesus and Buddha.

Science.gov (United States)

Duerksen, Kari N; Friedrich, Trista E; Elias, Lorin J

2015-10-02

People tend to exhibit a leftward bias in posing. Various studies suggest that posing to the left portrays a stronger emotion, whereas posing to the right portrays a more neutral emotion. Religions such as Christianity emphasize the role of strong emotions in religious experience, whereas religions such as Buddhism emphasize the calming of emotions as being important. In the present study, we investigated if the emphasis on emotionality of a religion influences the depiction of their religious figures. Specifically, we coded 484 paintings of Jesus and Buddha from online art databases for whether the deity exhibited a left bias, right bias, or central face presentation. The posing biases were analysed to discover whether paintings of Jesus would more frequently depict a leftward bias than paintings of Buddha. Jesus is more commonly depicted with a leftward bias than Buddha, and Buddha is more commonly depicted with a central face presentation than Jesus. These findings support the idea that the amount of emotionality that is to be conveyed in artwork influences the whether the subject is posed with a leftward bias.

Mitigating the Risk of Environmental Hazards in Mexico

Science.gov (United States)

2011-10-28

wildfires.9 Infectious hazards in Mexico pose an intermediate risk of disease and include food or waterborne illness, hepatitis, dengue fever , Valley Fever ...the type of health threat that is posed. 12 Nanotechnology: Within the Latin American region , Brazil , Argentina and Mexico are leaders in...07/25/ dengue -on-the-loose/ (accessed 11 October 2011). 41. Environmental Protection Agency, State of the Border Region Indicators Report 2005, EPA

Head Pose Estimation on Top of Haar-Like Face Detection: A Study Using the Kinect Sensor

Directory of Open Access Journals (Sweden)

Anwar Saeed

2015-08-01

Full Text Available Head pose estimation is a crucial initial task for human face analysis, which is employed in several computer vision systems, such as: facial expression recognition, head gesture recognition, yawn detection, etc. In this work, we propose a frame-based approach to estimate the head pose on top of the Viola and Jones (VJ Haar-like face detector. Several appearance and depth-based feature types are employed for the pose estimation, where comparisons between them in terms of accuracy and speed are presented. It is clearly shown through this work that using the depth data, we improve the accuracy of the head pose estimation. Additionally, we can spot positive detections, faces in profile views detected by the frontal model, that are wrongly cropped due to background disturbances. We introduce a new depth-based feature descriptor that provides competitive estimation results with a lower computation time. Evaluation on a benchmark Kinect database shows that the histogram of oriented gradients and the developed depth-based features are more distinctive for the head pose estimation, where they compare favorably to the current state-of-the-art approaches. Using a concatenation of the aforementioned feature types, we achieved a head pose estimation with average errors not exceeding 5:1; 4:6; 4:2 for pitch, yaw and roll angles, respectively.

Multivariate operational risk: dependence modelling with Lévy copulas

OpenAIRE

Böcker, K. and Klüppelberg, C.

2015-01-01

Simultaneous modelling of operational risks occurring in different event type/business line cells poses the challenge for operational risk quantification. Invoking the new concept of L´evy copulas for dependence modelling yields simple approximations of high quality for multivariate operational VAR.

Economics and management of climate change: risks, mitigation and adaptation

National Research Council Canada - National Science Library

Antes, Ralf

2008-01-01

... climate change poses risks to societies and companies, nor about adequate strategies to cope with these risks. Bringing together scholars from environmental economics, political science, and business management, this book describes, analyses and evaluates climate change risks and responses of societies and companies. The book c...

Renewable energy stocks and risk : (systematic risk factors in the renewable energy sector)

OpenAIRE

Strømme, Janne

2016-01-01

The renewable energy sector is an industry that expects tremendously growth in years to come. This opens interesting investment opportunities for investors and poses challenges for government and legislators as to how to best support the change to a low-carbon emission energy mix. In this study, we have explored the risk and returns characteristics for stocks, focusing on macroeconomic systematic risk. The stock returns from renewable energy sector was regressed on the macroeconomic variables...

Control and System Theory, Optimization, Inverse and Ill-Posed Problems

Science.gov (United States)

1988-09-14

Justlfleatlen Distribut ion/ Availability Codes # AFOSR-87-0350 Avat’ and/or1987-1988 Dist Special *CONTROL AND SYSTEM THEORY , ~ * OPTIMIZATION, * INVERSE...considerable va- riety of research investigations within the grant areas (Control and system theory , Optimization, and Ill-posed problems]. The

Reference manual for toxicity and exposure assessment and risk characterization. CERCLA Baseline Risk Assessment

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-03-01

The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, 1980) (CERCLA or Superfund) was enacted to provide a program for identifying and responding to releases of hazardous substances into the environment. The Superfund Amendments and Reauthorization Act (SARA, 1986) was enacted to strengthen CERCLA by requiring that site clean-ups be permanent, and that they use treatments that significantly reduce the volume, toxicity, or mobility of hazardous pollutants. The National Oil and Hazardous Substances Pollution Contingency Plan (NCP) (USEPA, 1985; USEPA, 1990) implements the CERCLA statute, presenting a process for (1) identifying and prioritizing sites requiring remediation and (2) assessing the extent of remedial action required at each site. The process includes performing two studies: a Remedial Investigation (RI) to evaluate the nature, extent, and expected consequences of site contamination, and a Feasibility Study (FS) to select an appropriate remedial alternative adequate to reduce such risks to acceptable levels. An integral part of the RI is the evaluation of human health risks posed by hazardous substance releases. This risk evaluation serves a number of purposes within the overall context of the RI/FS process, the most essential of which is to provide an understanding of ``baseline`` risks posed by a given site. Baseline risks are those risks that would exist if no remediation or institutional controls are applied at a site. This document was written to (1) guide risk assessors through the process of interpreting EPA BRA policy and (2) help risk assessors to discuss EPA policy with regulators, decision makers, and stakeholders as it relates to conditions at a particular DOE site.

Reference manual for toxicity and exposure assessment and risk characterization. CERCLA Baseline Risk Assessment

International Nuclear Information System (INIS)

1995-03-01

The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, 1980) (CERCLA or Superfund) was enacted to provide a program for identifying and responding to releases of hazardous substances into the environment. The Superfund Amendments and Reauthorization Act (SARA, 1986) was enacted to strengthen CERCLA by requiring that site clean-ups be permanent, and that they use treatments that significantly reduce the volume, toxicity, or mobility of hazardous pollutants. The National Oil and Hazardous Substances Pollution Contingency Plan (NCP) (USEPA, 1985; USEPA, 1990) implements the CERCLA statute, presenting a process for (1) identifying and prioritizing sites requiring remediation and (2) assessing the extent of remedial action required at each site. The process includes performing two studies: a Remedial Investigation (RI) to evaluate the nature, extent, and expected consequences of site contamination, and a Feasibility Study (FS) to select an appropriate remedial alternative adequate to reduce such risks to acceptable levels. An integral part of the RI is the evaluation of human health risks posed by hazardous substance releases. This risk evaluation serves a number of purposes within the overall context of the RI/FS process, the most essential of which is to provide an understanding of ''baseline'' risks posed by a given site. Baseline risks are those risks that would exist if no remediation or institutional controls are applied at a site. This document was written to (1) guide risk assessors through the process of interpreting EPA BRA policy and (2) help risk assessors to discuss EPA policy with regulators, decision makers, and stakeholders as it relates to conditions at a particular DOE site

Credit risk transfer activities and systemic risk : How banks became less risky individually but posed greater risks to the financial system at the same time

NARCIS (Netherlands)

Wagner, W.B.; Nijskens, R.G.M.

2011-01-01

A main cause of the crisis of 2007–2009 is the various ways through which banks have transferred credit risk in the financial system. We study the systematic risk of banks before the crisis, using two samples of banks respectively trading Credit Default Swaps (CDS) and issuing Collateralized Loan

Multifocal, chronic osteomyelitis of unknown etiology

International Nuclear Information System (INIS)

Kozlowski, K.; Beluffi, G.; Feltham, C.; James, M.; Nespoli, L.; Tamaela, L.; Pavia Univ.; Municipal Hospital, Nelson; Medical School, Jakarta

1985-01-01

Four cases of multifocal osteomyelitis of unknown origin in childhood are reported. The variable clinical and radiographic appearances of the disease are illustrated and the diagnostic difficulties in the early stages of the disease are stressed. (orig.) [de

Risk assessment of radon in drinking water

National Research Council Canada - National Science Library

Committee on Risk Assessment of Exposure to Radon in Drinking Water, National Research Council

.... This book presents a valuable synthesis of information about the total inhalation and ingestion risks posed by radon in public drinking water, including comprehensive reviews of data on the transfer...

Relative Pose Estimation and Accuracy Verification of Spherical Panoramic Image

Directory of Open Access Journals (Sweden)

XIE Donghai

2017-11-01

Full Text Available This paper improves the method of the traditional 5-point relative pose estimation algorithm, and proposes a relative pose estimation algorithm which is suitable for spherical panoramic images. The algorithm firstly computes the essential matrix, then decomposes the essential matrix to obtain the rotation matrix and the translation vector using SVD, and finally the reconstructed three-dimensional points are used to eliminate the error solution. The innovation of the algorithm lies the derivation of panorama epipolar formula and the use of the spherical distance from the point to the epipolar plane as the error term for the spherical panorama co-planarity function. The simulation experiment shows that when the random noise of the image feature points is within the range of pixel, the error of the three Euler angles is about 0.1°, and the error between the relative translational displacement and the simulated value is about 1.5°. The result of the experiment using the data obtained by the vehicle panorama camera and the POS shows that:the error of the roll angle and pitch angle can be within 0.2°, the error of the heading angle can be within 0.4°, and the error between the relative translational displacement and the POS can be within 2°. The result of our relative pose estimation algorithm is used to generate the spherical panoramic epipolar images, then we extract the key points between the spherical panoramic images and calculate the errors in the column direction. The result shows that the errors is less than 1 pixel.

Potential human health risks from metals and As via Odontesthes bonariensis consumption and ecological risk assessments in a eutrophic lake.

Science.gov (United States)

Monferran, Magdalena V; Garnero, Paola Lorena; Wunderlin, Daniel A; Bistoni, María de los Angeles

2016-07-01

The concentration of Al, Cr, Fe, Mn, Ni, Cu, Zn, Hg, Sr, Mo, Ag, Cd, Pb and As was analyzed in water, sediment, and muscle of Odontesthes bonariensis from the eutrophic San Roque Lake (Córdoba-Argentina). The monitoring campaign was performed during the wet, dry and intermediate season. The concentration of Cr, Fe, Pb, Zn, Al and Cd in water exceeded the limits considered as hazardous for aquatic life. The highest metal concentrations were observed in sediment, intermediate concentrations, in fish muscle, and the lowest in water, with the exception of Cr, Zn, As and Hg, which were the highest in fish muscle. Potential ecological risk analysis of heavy metal concentrations in sediment indicated that the San Roque Lake posed a low ecological risk in all sampling periods. The target hazard quotients (THQs) and carcinogenic risk (CR) for individual metals showed that As in muscle was particularly hazardous, posing a potential risk for fishermen and the general population during all sampling periods. Hg poses a potential risk for fishermen only in the intermediate season. It is important to highlight that none of these two elements exceeded the limits considered as hazardous for aquatic life in water and sediment. This result proves the importance of performing measurements of contaminants, in both abiotic and biotic compartments, to assess the quality of food resources. These results suggest that the consumption of this fish species from this reservoir is not completely safe for human health. Copyright © 2016 Elsevier Inc. All rights reserved.

Protocol for counterfactually transporting an unknown qubit

Directory of Open Access Journals (Sweden)

Hatim eSalih

2016-01-01

Full Text Available Quantum teleportation circumvents the uncertainty principle using dual channels: a quantum one consisting of previously-shared entanglement, and a classical one, together allowing the disembodied transport of an unknown quantum state over distance. It has recently been shown that a classical bit can be counterfactually communicated between two parties in empty space, Alice and Bob. Here, by using our dual version of the chained quantum Zeno effect to achieve a counterfactual CNOT gate, we propose a protocol for transporting an unknown qubit counterfactually, that is without any physical particles travelling between Alice and Bob—no classical channel and no previously-shared entanglement.

Glory on Venus and selection among the unknown UV absorbers

Science.gov (United States)

Petrova, Elena V.

2018-05-01

The comparison of the phase profiles of glories observed on the cloud top of Venus by the Venus Monitoring Camera (Venus Express) and the light-scattering characteristics of sulfuric acid droplets, containing admixtures with a high refractive index, makes it easier to choose between some candidates for the so-called unknown UV absorber in the Venus clouds. Since among the candidates there are materials wetted and not wetted by sulfuric acid, we analyze whether small submicron particles adhered to or embedded into the 1-μm H2SO4 droplets may actually change the glory pattern normally produced by homogeneous spherical particles and what the conditions are, under which the composite particles formed in heterogeneous nucleation may still produce a glory feature. We have found that one of the most frequently considered candidates, sulfur, can hardly be responsible for the contrasts observed at 0.365 μm on the upper clouds, since it is not wetted by sulfuric acid and submicron sulfur particles, serving as condensation nuclei for sulfuric acid, can only adhere to the H2SO4 droplets rather than be enveloped by them. Such droplets decorated by sulfur blobs substantially distort the glory feature characteristic of the scattering by spherical particles or even smooth it at all, while a glory pattern is practically always seen in the images of Venus taken at small phase angles. At the same time, the grains of the other UV absorbers that can be embedded in H2SO4 droplets, e.g., the widely discussed ferric chloride, pose no problem in terms of interpretation of the observations of glory.

Risk selection and risk adjustment: improving insurance in the individual and small group markets.

Science.gov (United States)

Baicker, Katherine; Dow, William H

2009-01-01

Insurance market reforms face the key challenge of addressing the threat that risk selection poses to the availability, of stable, high-value insurance policies that provide long-term risk protection. Many of the strategies in use today fail to address this breakdown in risk pooling, and some even exacerbate it. Flexible risk adjustment schemes are a promising avenue for promoting market stability and limiting insurer cream-skimming, potentially providing greater benefits at lower cost. Reforms intended to increase insurance coverage and the value of care delivered will be much more effective if implemented in conjunction with policies that address these fundamental selection issues.

ULTOR(Registered TradeMark) Passive Pose and Position Engine For Spacecraft Relative Navigation

Science.gov (United States)

Hannah, S. Joel

2008-01-01

The ULTOR(Registered TradeMark) Passive Pose and Position Engine (P3E) technology, developed by Advanced Optical Systems, Inc (AOS), uses real-time image correlation to provide relative position and pose data for spacecraft guidance, navigation, and control. Potential data sources include a wide variety of sensors, including visible and infrared cameras. ULTOR(Registered TradeMark) P3E has been demonstrated on a number of host processing platforms. NASA is integrating ULTOR(Registerd TradeMark) P3E into its Relative Navigation System (RNS), which is being developed for the upcoming Hubble Space Telescope (HST) Servicing Mission 4 (SM4). During SM4 ULTOR(Registered TradeMark) P3E will perform realtime pose and position measurements during both the approach and departure phases of the mission. This paper describes the RNS implementation of ULTOR(Registered TradeMark) P3E, and presents results from NASA's hardware-in-the-loop simulation testing against the HST mockup.

A problem-posing approach to teaching the topic of radioactivity

NARCIS (Netherlands)

Klaassen, C.W.J.M.

1995-01-01

This thesis highlights a problem-posing approach to science education. By this is meant an approach that explicitly aims at providing students with content-related motives for extending their existing conceptual resources, experiential base and belief system in a certain direction, such that a

Effects of pose and image resolution on automatic face recognition

NARCIS (Netherlands)

Mahmood, Zahid; Ali, Tauseef; Khan, Samee U.

The popularity of face recognition systems have increased due to their use in widespread applications. Driven by the enormous number of potential application domains, several algorithms have been proposed for face recognition. Face pose and image resolutions are among the two important factors that

Fever of unknown origin

International Nuclear Information System (INIS)

Misaki, Takashi; Matsui, Akira; Tanaka, Fumiko; Okuno, Yoshishige; Mitsumori, Michihide; Torizuka, Tatsurou; Dokoh, Shigeharu; Hayakawa, Katsumi; Shimbo, Shin-ichirou

1990-01-01

Gallium-67 scintigraphy is a commonly performed imaging modality in deteting pyrogenic lesions in cases of long-standing inexplainable fever. To re-evaluate the significance of gallium imaging in such cases, a retrospective review was made of 56 scans performed in febrile patients in whom sufficient clinical and laboratory findings were obtained. Gallium scans were true positive in 30 patients, false positive in 3, true negative in 19, and false negative in 4. In the group of true positive, local inflammatory lesions were detected in 23 patients with a final diagnosis of lung tuberculosis, urinary tract infection, and inflammatory joint disease. Abnormal gallium accumulation, as shown in the other 7 patients, provided clues to the diagnosis of generalized disorders, such as hematological malignancies (n=3), systemic autoimmune diseases (n=3), and severe infectious mononucleosis (n=one). In the group of false positive, gallium imaging revealed intestinal excretion of gallium in 2 patients and physiological pulmonary hilar accumulation in one. In the true negative group of 19 patients, fever of unknown origin was resolved spontaneously in 12 patients, and with antibiotics and corticosteroids in 2 and 5 patients, respectively. Four patients having false negative scans were finally diagnosed as having urinary tract infection (n=2), bacterial meningitis (n=one), and polyarteritis (n=one). Gallium imaging would remain the technique of choice in searching for origin of unknown fever. It may also be useful for early diagnosis of systemic disease, as well as focal inflammation. (N.K.)

Regularization theory for ill-posed problems selected topics

CERN Document Server

Lu, Shuai

2013-01-01

Thismonograph is a valuable contribution to thehighly topical and extremly productive field ofregularisationmethods for inverse and ill-posed problems. The author is an internationally outstanding and acceptedmathematicianin this field. In his book he offers a well-balanced mixtureof basic and innovative aspects.He demonstrates new,differentiatedviewpoints, and important examples for applications. The bookdemontrates thecurrent developments inthe field of regularization theory,such as multiparameter regularization and regularization in learning theory. The book is written for graduate and PhDs

Framing risk and uncertainty in social science articles on climate change, 1995–2012

OpenAIRE

Shaw, Chris; Hellsten, Iina; Nerlich, Brigitte

2016-01-01

The issue of climate change is intimately linked to notions of risk and uncertainty, concepts that pose challenges to climate science, climate change communication, and science-society interactions. While a large majority of climate scientists are increasingly certain about the causes of climate change and the risks posed by its impacts (see IPCC, 2013 and 2014), public perception of climate change is still largely framed by uncertainty, especially regarding impacts (Poortinga et al., 2011). ...

Air quality risk management.

Science.gov (United States)

Williams, Martin L

2008-01-01

Rather than attempt to provide a comprehensive account of air quality risk assessment, as might be found in a textbook or manual, this article discusses some issues that are of current importance in the United Kingdom and the rest of Europe, with special emphasis on risk assessment in the context of policy formulation, and emerging scientific knowledge. There are two pollutants of particular concern and that both pose challenges for risk assessment and policy, and they are particulate matter (PM) and ozone. The article describes some issues for health risk assessment and finally some forward-looking suggestions for future approaches to air quality management.

Chemical Mixtures Health Risk Assessment of Environmental Contaminants: Concepts, Methods, And Applications

Science.gov (United States)

This problems-based, introductory workshop focuses on methods to assess health risks posed by exposures to chemical mixtures in the environment. Chemical mixtures health risk assessment methods continue to be developed and evolve to address concerns over health risks from multic...

A global airport-based risk model for the spread of dengue infection via the air transport network.

Directory of Open Access Journals (Sweden)

Lauren Gardner

Full Text Available The number of travel-acquired dengue infections has seen a consistent global rise over the past decade. An increased volume of international passenger air traffic originating from regions with endemic dengue has contributed to a rise in the number of dengue cases in both areas of endemicity and elsewhere. This paper reports results from a network-based risk assessment model which uses international passenger travel volumes, travel routes, travel distances, regional populations, and predictive species distribution models (for the two vector species, Aedes aegypti and Aedes albopictus to quantify the relative risk posed by each airport in importing passengers with travel-acquired dengue infections. Two risk attributes are evaluated: (i the risk posed by through traffic at each stopover airport and (ii the risk posed by incoming travelers to each destination airport. The model results prioritize optimal locations (i.e., airports for targeted dengue surveillance. The model is easily extendible to other vector-borne diseases.

A New Pose Estimation Algorithm Using a Perspective-Ray-Based Scaled Orthographic Projection with Iteration.

Directory of Open Access Journals (Sweden)

Pengfei Sun

Full Text Available Pose estimation aims at measuring the position and orientation of a calibrated camera using known image features. The pinhole model is the dominant camera model in this field. However, the imaging precision of this model is not accurate enough for an advanced pose estimation algorithm. In this paper, a new camera model, called incident ray tracking model, is introduced. More importantly, an advanced pose estimation algorithm based on the perspective ray in the new camera model, is proposed. The perspective ray, determined by two positioning points, is an abstract mathematical equivalent of the incident ray. In the proposed pose estimation algorithm, called perspective-ray-based scaled orthographic projection with iteration (PRSOI, an approximate ray-based projection is calculated by a linear system and refined by iteration. Experiments on the PRSOI have been conducted, and the results demonstrate that it is of high accuracy in the six degrees of freedom (DOF motion. And it outperforms three other state-of-the-art algorithms in terms of accuracy during the contrast experiment.

PRA has many faces - can the safety goal be well-posed

International Nuclear Information System (INIS)

Bargmann, H.

1983-01-01

The question is discussed whether probabilistic reliability problems can, principally, be well-posed in practical situations. The problem is reduced to the question whether an underlying probabilistic experiment which is, essentially, the set of outcomes can be precisely specified such that the solution of the problem is unique. Upon reexamination of a classical paradox due to Bertrand and consideration of a typical problem of structural reliability we conclude that the possibility of well-posing a reliability problem should be considered illusory, for fundamental reasons which are inherent in practical situations. In particular, it should not be assumed that a quantitative safety goal could be verified. Generally, a probabilistic assessment should be considered as a quantitative method for establishing rational results which should, however, not be viewed as quantitative measures but as qualitative guides

Estimation de pose omnidirectionnelle dans un contexte de réalité augmentée

OpenAIRE

Poirier, Stéphane

2012-01-01

Estimer la pose de la caméra est un défi fondamental en réalité augmentée et permet la superposition d’un modèle à la réalité. Estimer précisément la pose est souvent critique en ingénierie d’infrastructures. Les images omnidirectionnelles ont un champ de vision supérieur aux images planaires communément utilisées en RA. Cette propriété peut bénéficier à l’estimation de la pose. Or, aucun travail ne présente de résultats montrant clairement un gain de précision. Notre objectif est de quantifi...

NIH Researchers Identify OCD Risk Gene

Science.gov (United States)

... News From NIH NIH Researchers Identify OCD Risk Gene Past Issues / Summer 2006 Table of Contents For ... and Alcoholism (NIAAA) have identified a previously unknown gene variant that doubles an individual's risk for obsessive- ...

Pose Measurement Method and Experiments for High-Speed Rolling Targets in a Wind Tunnel

Directory of Open Access Journals (Sweden)

Zhenyuan Jia

2014-12-01

Full Text Available High-precision wind tunnel simulation tests play an important role in aircraft design and manufacture. In this study, a high-speed pose vision measurement method is proposed for high-speed and rolling targets in a supersonic wind tunnel. To obtain images with high signal-to-noise ratio and avoid impacts on the aerodynamic shape of the rolling targets, a high-speed image acquisition method based on ultrathin retro-reflection markers is presented. Since markers are small-sized and some of them may be lost when the target is rolling, a novel markers layout with which markers are distributed evenly on the surface is proposed based on a spatial coding method to achieve highly accurate pose information. Additionally, a pose acquisition is carried out according to the mentioned markers layout after removing mismatching points by Case Deletion Diagnostics. Finally, experiments on measuring the pose parameters of high-speed targets in the laboratory and in a supersonic wind tunnel are conducted to verify the feasibility and effectiveness of the proposed method. Experimental results indicate that the position measurement precision is less than 0.16 mm, the pitching and yaw angle precision less than 0.132° and the roll angle precision 0.712°.

Pose measurement method and experiments for high-speed rolling targets in a wind tunnel.

Science.gov (United States)

Jia, Zhenyuan; Ma, Xin; Liu, Wei; Lu, Wenbo; Li, Xiao; Chen, Ling; Wang, Zhengqu; Cui, Xiaochun

2014-12-12

High-precision wind tunnel simulation tests play an important role in aircraft design and manufacture. In this study, a high-speed pose vision measurement method is proposed for high-speed and rolling targets in a supersonic wind tunnel. To obtain images with high signal-to-noise ratio and avoid impacts on the aerodynamic shape of the rolling targets, a high-speed image acquisition method based on ultrathin retro-reflection markers is presented. Since markers are small-sized and some of them may be lost when the target is rolling, a novel markers layout with which markers are distributed evenly on the surface is proposed based on a spatial coding method to achieve highly accurate pose information. Additionally, a pose acquisition is carried out according to the mentioned markers layout after removing mismatching points by Case Deletion Diagnostics. Finally, experiments on measuring the pose parameters of high-speed targets in the laboratory and in a supersonic wind tunnel are conducted to verify the feasibility and effectiveness of the proposed method. Experimental results indicate that the position measurement precision is less than 0.16 mm, the pitching and yaw angle precision less than 0.132° and the roll angle precision 0.712°.

Mathematical Thinking and Creativity through Mathematical Problem Posing and Solving

Science.gov (United States)

Ayllón, María F.; Gómez, Isabel A.; Ballesta-Claver, Julio

2016-01-01

This work shows the relationship between the development of mathematical thinking and creativity with mathematical problem posing and solving. Creativity and mathematics are disciplines that do not usually appear together. Both concepts constitute complex processes sharing elements, such as fluency (number of ideas), flexibility (range of ideas),…

Some thoughts about risk

International Nuclear Information System (INIS)

Jennekens, J.H.

1986-05-01

The author discusses how the concept of risk is perceived differently by the scientist and the man in the street, and mentions the problems that this can sometimes pose for the regulator. He also gives examples of inconsistencies and contradictions in various areas of risk management. He concludes by noting that so-called accidents usually do not occur by chance, but that system or component failures are always due to some form of human error. The objective of risk management is to ensure, by a process of rigorous analysis, that both the probability and consequences of such failures are minimized

Hair testing to assess both known and unknown use of drugs amongst ecstasy users in the electronic dance music scene.

Science.gov (United States)

Palamar, Joseph J; Salomone, Alberto; Gerace, Enrico; Di Corcia, Daniele; Vincenti, Marco; Cleland, Charles M

2017-10-01

Data on both known and unknown drug use in the electronic dance music (EDM) scene is important to inform prevention and harm reduction. While surveys are the most common method of querying drug use, additional biological data can help validate use and detect unknown/unintentional use of drugs such as new psychoactive substances (NPS). We sought to determine the extent of both known and unknown use of various substances in this high-risk scene. We hair-tested 90 self-reported past-year ecstasy/MDMA/Molly users attending EDM parties in New York City during the summer of 2016 using UHPLC-MS/MS. Results were compared to self-reported past-year use. Three quarters (74.4%) tested positive for MDMA, a third (33.3%) tested positive for an NPS, and 27.8% tested positive specifically for one or more synthetic cathinones (e.g., butylone, ethylone, pentylone, methylone, alpha-PVP). Half (51.1%) of participants tested positive for a drug not self-reported, with most testing positive for synthetic cathinones (72.0%), methamphetamine (69.0%), other NPS stimulants (e.g., 4-FA, 5/6-APB; 66.7%), or new dissociatives (e.g., methoxetamine, diphenidine; 60.0%). Attending parties every other week or more often, reporting higher-frequency ecstasy pill use, having tested one's ecstasy, and having found out one's ecstasy was adulterated, were risk factors for testing positive for synthetic cathinones and NPS in general. Hair testing appears to be a valuable addition to drug epidemiology studies. Many EDM party attendees-even those who test their ecstasy-are unknowingly using NPS and/or other drugs. Prevention information and harm reduction may help reduce unknown/unintentional use. Copyright © 2017 Elsevier B.V. All rights reserved.

Quantum jointly assisted cloning of an unknown three-dimensional equatorial state

Science.gov (United States)

Ma, Peng-Cheng; Chen, Gui-Bin; Li, Xiao-Wei; Zhan, You-Bang

2018-02-01

We present two schemes for perfectly cloning an unknown single-qutrit equatorial state with assistance from two and N state preparers, respectively. In the first scheme, the sender wishes to teleport an unknown single-qutrit equatorial state from two state preparers to a remote receiver, and then to create a perfect copy of the unknown state at her location. The scheme consists of two stages. The first stage of the scheme requires the usual teleportation. In the second stage, to help the sender realize the quantum cloning, two state preparers perform single-qutrit projective measurements on their own qutrits from the sender, then the sender can acquire a perfect copy of the unknown state. It is shown that, only if the two state preparers collaborate with each other, the sender can create a copy of the unknown state by means of some appropriate unitary operations. In the second scheme, we generalized the jointly assisted cloning in the first scheme to the case of N state prepares. In the present schemes, the total probability of success for assisted cloning of a perfect copy of the unknown state can reach 1.

Crash fatality risk and unibody versus body-on-frame structure in SUVs.

Science.gov (United States)

Ossiander, Eric M; Koepsell, Thomas D; McKnight, Barbara

2014-09-01

In crashes between cars and SUVs, car occupants are more likely to be killed than if they crashed with another car. An increasing proportion of SUVs are built with unibody, rather than truck-like body-on-frame construction. Unibody SUVs are generally lighter, less stiff, and less likely to roll over than body-on-frame SUVs, but whether unibody structure affects risk of death in crashes is unknown. To determine whether unibody SUVs differ from body-on-frame SUVs in the danger they pose to occupants of other vehicles and in the self-protection they offer to their own occupants. Case-control study of crashes between one compact SUV and one other passenger vehicle in the US during 1995-2008, in which the SUV was model year 1996-2006. Cases were all decedents in fatal crashes, one control was selected from each non-fatal crash. Occupants of passenger vehicles that crashed with compact unibody SUVs were at 18% lower risk of death compared to those that crashed with compact body-on-frame SUVs (adjusted odds ratio 0.82 (95% confidence interval 0.73-0.94)). Occupants of compact unibody SUVs were also at lower risk of death compared to occupants of body-on-frame SUVs (0.86 (0.72-1.02)). In two-vehicle collisions involving compact SUVs, unibody structure was associated with lower risk of death both in occupants of other vehicles in the crash, and in SUVs' own occupants. Copyright © 2014 Elsevier Ltd. All rights reserved.

Absolute stability results for well-posed infinite-dimensional systems with applications to low-gain integral control

NARCIS (Netherlands)

Logemann, H; Curtain, RF

2000-01-01

We derive absolute stability results for well-posed infinite-dimensional systems which, in a sense, extend the well-known circle criterion to the case that the underlying linear system is the series interconnection of an exponentially stable well-posed infinite-dimensional system and an integrator

Multi-view 3D human pose estimation combining single-frame recovery, temporal integration and model adaptation

NARCIS (Netherlands)

Hofmann, K.M.; Gavrilla, D.M.

2009-01-01

We present a system for the estimation of unconstrained 3D human upper body movement from multiple cameras. Its main novelty lies in the integration of three components: single frame pose recovery, temporal integration and model adaptation. Single frame pose recovery consists of a hypothesis

Seismic risks posed by mine flooding

CSIR Research Space (South Africa)

Goldbach, OD

2009-09-01

Full Text Available are allowed to flood. Such flooding-induced seismicity can have significant environmental, social and economic consequences, and may endanger neighbouring mines and surface communities. While fluid-induced seismicity has been observed in other settings (e...

A Risk-Based Multi-Objective Optimization Concept for Early-Warning Monitoring Networks

Science.gov (United States)

Bode, F.; Loschko, M.; Nowak, W.

2014-12-01

Groundwater is a resource for drinking water and hence needs to be protected from contaminations. However, many well catchments include an inventory of known and unknown risk sources which cannot be eliminated, especially in urban regions. As matter of risk control, all these risk sources should be monitored. A one-to-one monitoring situation for each risk source would lead to a cost explosion and is even impossible for unknown risk sources. However, smart optimization concepts could help to find promising low-cost monitoring network designs.In this work we develop a concept to plan monitoring networks using multi-objective optimization. Our considered objectives are to maximize the probability of detecting all contaminations and the early warning time and to minimize the installation and operating costs of the monitoring network. A qualitative risk ranking is used to prioritize the known risk sources for monitoring. The unknown risk sources can neither be located nor ranked. Instead, we represent them by a virtual line of risk sources surrounding the production well.We classify risk sources into four different categories: severe, medium and tolerable for known risk sources and an extra category for the unknown ones. With that, early warning time and detection probability become individual objectives for each risk class. Thus, decision makers can identify monitoring networks which are valid for controlling the top risk sources, and evaluate the capabilities (or search for least-cost upgrade) to also cover moderate, tolerable and unknown risk sources. Monitoring networks which are valid for the remaining risk also cover all other risk sources but the early-warning time suffers.The data provided for the optimization algorithm are calculated in a preprocessing step by a flow and transport model. Uncertainties due to hydro(geo)logical phenomena are taken into account by Monte-Carlo simulations. To avoid numerical dispersion during the transport simulations we use the

Precise 3D Lug Pose Detection Sensor for Automatic Robot Welding Using a Structured-Light Vision System

Directory of Open Access Journals (Sweden)

Il Jae Lee

2009-09-01

Full Text Available In this study, we propose a precise 3D lug pose detection sensor for automatic robot welding of a lug to a huge steel plate used in shipbuilding, where the lug is a handle to carry the huge steel plate. The proposed sensor consists of a camera and four laser line diodes, and its design parameters are determined by analyzing its detectable range and resolution. For the lug pose acquisition, four laser lines are projected on both lug and plate, and the projected lines are detected by the camera. For robust detection of the projected lines against the illumination change, the vertical threshold, thinning, Hough transform and separated Hough transform algorithms are successively applied to the camera image. The lug pose acquisition is carried out by two stages: the top view alignment and the side view alignment. The top view alignment is to detect the coarse lug pose relatively far from the lug, and the side view alignment is to detect the fine lug pose close to the lug. After the top view alignment, the robot is controlled to move close to the side of the lug for the side view alignment. By this way, the precise 3D lug pose can be obtained. Finally, experiments with the sensor prototype are carried out to verify the feasibility and effectiveness of the proposed sensor.

PICOREF: carbon sequestration in geological reservoirs in France.Map of the unknown ''ground motion''. Final report

International Nuclear Information System (INIS)

Rohmer, J.; Lembezat, C.

2006-01-01

in the framework of the PICOREF project, ''CO 2 sequestration in geological reservoirs in France'', two main objectives are decided: the characterization of french adapted sites and the redaction of a document to ask for the storage authorization, including a methodology to survey and study the storage site. This report aims to define the unknown ground motion which the impact should present a risk for the surface installations. The project is presented, as the geological context and the proposed methodology. (A.L.B.)

Iterative Selection of Unknown Weights in Direct Weight Optimization Identification

Directory of Open Access Journals (Sweden)

Xiao Xuan

2014-01-01

Full Text Available To the direct weight optimization identification of the nonlinear system, we add some linear terms about input sequences in the former linear affine function so as to approximate the nonlinear property. To choose the two classes of unknown weights in the more linear terms, this paper derives the detailed process on how to choose these unknown weights from theoretical analysis and engineering practice, respectively, and makes sure of their key roles between the unknown weights. From the theoretical analysis, the added unknown weights’ auxiliary role can be known in the whole process of approximating the nonlinear system. From the practical analysis, we learn how to transform one complex optimization problem to its corresponding common quadratic program problem. Then, the common quadratic program problem can be solved by the basic interior point method. Finally, the efficiency and possibility of the proposed strategies can be confirmed by the simulation results.

Emerging Risk Factors and Prevention of Perioperative Pulmonary Complications

Directory of Open Access Journals (Sweden)

Priyanka Bhateja

2014-01-01

Full Text Available Modern surgery is faced with the emergence of newer “risk factors” and the challenges associated with identifying and managing these risks in the perioperative period. Obstructive sleep apnea and obesity hypoventilation syndrome pose unique challenges in the perioperative setting. Recent studies have identified some of the specific risks arising from caring for such patients in the surgical setting. While all possible postoperative complications are not yet fully established or understood, the prevention and management of these complications pose even greater challenges. Pulmonary hypertension with its changing epidemiology and novel management strategies is another new disease for the surgeon and the anesthesiologist in the noncardiac surgical setting. Traditionally most such patients were not considered surgical candidates for any required elective surgery. Our review discusses these disease entities which are often undiagnosed before elective noncardiac surgery.

A circular feature-based pose measurement method for metal part grasping

International Nuclear Information System (INIS)

Wu, Chenrui; He, Zaixing; Zhang, Shuyou; Zhao, Xinyue

2017-01-01

The grasping of circular metal parts such as bearings and flanges is a common task in industry. Limited by low texture and repeated features, the point-feature-based method is not applicable in pose measurement of these parts. In this paper, we propose a novel pose measurement method for grasping circular metal parts. This method is based on cone degradation and involves a monocular camera. To achieve higher measurement accuracy, a position-based visual servoing method is presented to continuously control an eye-in-hand, six-degrees-of-freedom robot arm to grasp the part. The uncertainty of the part’s coordinate frame during the control process is solved by defining a fixed virtual coordinate frame. Experimental results are provided to illustrate the effectiveness of the proposed method and the factors that affect measurement accuracy are analyzed. (paper)

Hardware in the Loop Performance Assessment of LIDAR-Based Spacecraft Pose Determination.

Science.gov (United States)

Opromolla, Roberto; Fasano, Giancarmine; Rufino, Giancarlo; Grassi, Michele

2017-09-24

In this paper an original, easy to reproduce, semi-analytic calibration approach is developed for hardware-in-the-loop performance assessment of pose determination algorithms processing point cloud data, collected by imaging a non-cooperative target with LIDARs. The laboratory setup includes a scanning LIDAR, a monocular camera, a scaled-replica of a satellite-like target, and a set of calibration tools. The point clouds are processed by uncooperative model-based algorithms to estimate the target relative position and attitude with respect to the LIDAR. Target images, acquired by a monocular camera operated simultaneously with the LIDAR, are processed applying standard solutions to the Perspective- n -Points problem to get high-accuracy pose estimates which can be used as a benchmark to evaluate the accuracy attained by the LIDAR-based techniques. To this aim, a precise knowledge of the extrinsic relative calibration between the camera and the LIDAR is essential, and it is obtained by implementing an original calibration approach which does not need ad-hoc homologous targets (e.g., retro-reflectors) easily recognizable by the two sensors. The pose determination techniques investigated by this work are of interest to space applications involving close-proximity maneuvers between non-cooperative platforms, e.g., on-orbit servicing and active debris removal.

Enantioselectivity in environmental risk assessment of modern chiral pesticides

International Nuclear Information System (INIS)

Ye Jing; Zhao Meirong; Liu Jing; Liu Weiping

2010-01-01

Chiral pesticides comprise a new and important class of environmental pollutants nowadays. With the development of industry, more and more chiral pesticides will be introduced into the market. But their enantioselective ecotoxicology is not clear. Currently used synthetic pyrethroids, organophosphates, acylanilides, phenoxypropanoic acids and imidazolinones often behave enantioselectively in agriculture use and they always pose unpredictable enantioselective ecological risks on non-target organisms or human. It is necessary to explore the enantioselective toxicology and ecological fate of these chiral pesticides in environmental risk assessment. The enantioselective toxicology and the fate of these currently widely used pesticides have been discussed in this review article. - Chiral pesticides could pose unpredictable enantioselective toxicity on non-target organisms.

Chaos Synchronization Based on Unknown Input Proportional Multiple-Integral Fuzzy Observer

Directory of Open Access Journals (Sweden)

T. Youssef

2013-01-01

Full Text Available This paper presents an unknown input Proportional Multiple-Integral Observer (PIO for synchronization of chaotic systems based on Takagi-Sugeno (TS fuzzy chaotic models subject to unmeasurable decision variables and unknown input. In a secure communication configuration, this unknown input is regarded as a message encoded in the chaotic system and recovered by the proposed PIO. Both states and outputs of the fuzzy chaotic models are subject to polynomial unknown input with kth derivative zero. Using Lyapunov stability theory, sufficient design conditions for synchronization are proposed. The PIO gains matrices are obtained by resolving linear matrix inequalities (LMIs constraints. Simulation results show through two TS fuzzy chaotic models the validity of the proposed method.

Characterizing unknown systematics in large scale structure surveys

International Nuclear Information System (INIS)

Agarwal, Nishant; Ho, Shirley; Myers, Adam D.; Seo, Hee-Jong; Ross, Ashley J.; Bahcall, Neta; Brinkmann, Jonathan; Eisenstein, Daniel J.; Muna, Demitri; Palanque-Delabrouille, Nathalie; Yèche, Christophe; Pâris, Isabelle; Petitjean, Patrick; Schneider, Donald P.; Streblyanska, Alina; Weaver, Benjamin A.

2014-01-01

Photometric large scale structure (LSS) surveys probe the largest volumes in the Universe, but are inevitably limited by systematic uncertainties. Imperfect photometric calibration leads to biases in our measurements of the density fields of LSS tracers such as galaxies and quasars, and as a result in cosmological parameter estimation. Earlier studies have proposed using cross-correlations between different redshift slices or cross-correlations between different surveys to reduce the effects of such systematics. In this paper we develop a method to characterize unknown systematics. We demonstrate that while we do not have sufficient information to correct for unknown systematics in the data, we can obtain an estimate of their magnitude. We define a parameter to estimate contamination from unknown systematics using cross-correlations between different redshift slices and propose discarding bins in the angular power spectrum that lie outside a certain contamination tolerance level. We show that this method improves estimates of the bias using simulated data and further apply it to photometric luminous red galaxies in the Sloan Digital Sky Survey as a case study

Characterizing unknown systematics in large scale structure surveys

Energy Technology Data Exchange (ETDEWEB)

Agarwal, Nishant; Ho, Shirley [McWilliams Center for Cosmology, Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213 (United States); Myers, Adam D. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States); Seo, Hee-Jong [Berkeley Center for Cosmological Physics, LBL and Department of Physics, University of California, Berkeley, CA 94720 (United States); Ross, Ashley J. [Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth, PO1 3FX (United Kingdom); Bahcall, Neta [Princeton University Observatory, Peyton Hall, Princeton, NJ 08544 (United States); Brinkmann, Jonathan [Apache Point Observatory, P.O. Box 59, Sunspot, NM 88349 (United States); Eisenstein, Daniel J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States); Muna, Demitri [Department of Astronomy, Ohio State University, Columbus, OH 43210 (United States); Palanque-Delabrouille, Nathalie; Yèche, Christophe [CEA, Centre de Saclay, Irfu/SPP, F-91191 Gif-sur-Yvette (France); Pâris, Isabelle [Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago (Chile); Petitjean, Patrick [Université Paris 6 et CNRS, Institut d' Astrophysique de Paris, 98bis blvd. Arago, 75014 Paris (France); Schneider, Donald P. [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Streblyanska, Alina [Instituto de Astrofisica de Canarias (IAC), E-38200 La Laguna, Tenerife (Spain); Weaver, Benjamin A., E-mail: nishanta@andrew.cmu.edu [Center for Cosmology and Particle Physics, New York University, New York, NY 10003 (United States)

2014-04-01

Photometric large scale structure (LSS) surveys probe the largest volumes in the Universe, but are inevitably limited by systematic uncertainties. Imperfect photometric calibration leads to biases in our measurements of the density fields of LSS tracers such as galaxies and quasars, and as a result in cosmological parameter estimation. Earlier studies have proposed using cross-correlations between different redshift slices or cross-correlations between different surveys to reduce the effects of such systematics. In this paper we develop a method to characterize unknown systematics. We demonstrate that while we do not have sufficient information to correct for unknown systematics in the data, we can obtain an estimate of their magnitude. We define a parameter to estimate contamination from unknown systematics using cross-correlations between different redshift slices and propose discarding bins in the angular power spectrum that lie outside a certain contamination tolerance level. We show that this method improves estimates of the bias using simulated data and further apply it to photometric luminous red galaxies in the Sloan Digital Sky Survey as a case study.

The impact of risk communications on public understanding

International Nuclear Information System (INIS)

O'Connor, R.E.; Bord, R.J.

1992-01-01

This paper assesses the impact of different modes of communicating information about risks that are cumulative, uncertain, and long-term (CULT). Do communications that emphasize potential ecological problems have a different impact from messages that discuss health concerns? Is a more emotional style more effective than a traditional standard approach? CULT risks, including those commonly associated with high-level radioactive waste, pose particular problems for risk communicators. nevertheless, the research shows that relatively simple risk communications can effectively lower risk estimates and reduce fears of negative consequences from CULT risks

Drug and alcohol crash risk : traffic safety facts : research note.

Science.gov (United States)

2015-02-01

While the extent of use of alcohol by drivers and the risks posed by alcohol use have been well known for many decades, relatively little has been known about the use of other drugs by drivers and the associated risks. However, drug-impaired driving ...

Villitis of unknown aetiology: correlation of recurrence with clinical outcome.

LENUS (Irish Health Repository)

Feeley, L

2010-01-01

Villitis of unknown aetiology (VUA) is associated with adverse pregnancy outcome. Consequently, an ability to predict recurrence could be clinically relevant. We examined placentas where villitis was diagnosed in a previous pregnancy to establish the risk of recurrence and outcome. A total of 304 cases of VUA were diagnosed in our laboratory over a 4-year period. Subsequently, 19 of this cohort had a second placenta examined histologically. Recurrence and clinical outcome were recorded. Villitis recurred in 7 of 19 cases (37%). There was a high level of adverse pregnancy outcome in this cohort overall, characterised by small for gestational age infants and stillbirth, particularly in cases with high-grade villitis. We identified recurrent villitis more frequently than previously reported. Our findings confirm an association between high-grade villitis and poor outcome. Adequately powered prospective studies are required to determine if enhanced surveillance of subsequent pregnancies is indicated following a diagnosis of villitis.

Perceptions of farmers on health risks and risk reduction measures in wastewater-irrigated urban vegetable farming in Ghana

DEFF Research Database (Denmark)

Keraita, Bernard; Drechsel, Pay; Konradsen, Flemming

2008-01-01

, authorities and the general public, especially if they had some incentives. These findings demonstrate the need to involve farmers as early as possible in intervention projects especially in informal farming practices, like urban agriculture, where restrictions are difficult to implement. This will ensure......Most irrigation water used in urban vegetable farming in Ghana is contaminated with untreated wastewater. This poses health risks to farmers and consumers. As part of a study to explore options for health risk reduction, this paper summarizes farmers' perceptions on health risks and possible risk...

Hazard classification or risk assessment

DEFF Research Database (Denmark)

Hass, Ulla

2013-01-01

The EU classification of substances for e.g. reproductive toxicants is hazard based and does not to address the risk suchsubstances may pose through normal, or extreme, use. Such hazard classification complies with the consumer's right to know. It is also an incentive to careful use and storage...

Factoring attitudes towards armed conflict risk into selection of protected areas for conservation

DEFF Research Database (Denmark)

Hammill, E.; Tulloch, A.I.T.; Possingham, H.P.

2016-01-01

The high incidence of armed conflicts in biodiverse regions poses significant challenges in achieving international conservation targets. Because attitudes towards risk vary, we assessed different strategies for protected area planning that reflected alternative attitudes towards the risk of arme...... that achieving biodiversity targets in volatile regions will require greater initial investment and benefit from fine-resolution estimates of conflict risk.......The high incidence of armed conflicts in biodiverse regions poses significant challenges in achieving international conservation targets. Because attitudes towards risk vary, we assessed different strategies for protected area planning that reflected alternative attitudes towards the risk of armed...... conflicts. We find that ignoring conflict risk will deliver the lowest return on investment. Opting to completely avoid conflict-prone areas offers limited improvements and could lead to species receiving no protection. Accounting for conflict by protecting additional areas to offset the impacts of armed...

Penalized linear regression for discrete ill-posed problems: A hybrid least-squares and mean-squared error approach

KAUST Repository

Suliman, Mohamed Abdalla Elhag; Ballal, Tarig; Kammoun, Abla; Al-Naffouri, Tareq Y.

2016-01-01

This paper proposes a new approach to find the regularization parameter for linear least-squares discrete ill-posed problems. In the proposed approach, an artificial perturbation matrix with a bounded norm is forced into the discrete ill-posed model

Robust Fault Detection for Switched Fuzzy Systems With Unknown Input.

Science.gov (United States)

Han, Jian; Zhang, Huaguang; Wang, Yingchun; Sun, Xun

2017-10-03

This paper investigates the fault detection problem for a class of switched nonlinear systems in the T-S fuzzy framework. The unknown input is considered in the systems. A novel fault detection unknown input observer design method is proposed. Based on the proposed observer, the unknown input can be removed from the fault detection residual. The weighted H∞ performance level is considered to ensure the robustness. In addition, the weighted H₋ performance level is introduced, which can increase the sensibility of the proposed detection method. To verify the proposed scheme, a numerical simulation example and an electromechanical system simulation example are provided at the end of this paper.

Five-year-olds do not show ambiguity aversion in a risk and ambiguity task with physical objects.

Science.gov (United States)

Li, Rosa; Roberts, Rachel C; Huettel, Scott A; Brannon, Elizabeth M

2017-07-01

Ambiguity aversion arises when a decision maker prefers risky gambles with known probabilities over equivalent ambiguous gambles with unknown probabilities. This phenomenon has been consistently observed in adults across a large body of empirical work. Evaluating ambiguity aversion in young children, however, has posed methodological challenges because probabilistic representations appropriate for adults might not be understood by young children. Here, we established a novel method for representing risk and ambiguity with physical objects that overcomes previous methodological limitations and allows us to measure ambiguity aversion in young children. We found that individual 5-year-olds exhibited consistent choice preferences and, as a group, exhibited no ambiguity aversion in a task that evokes ambiguity aversion in adults. Across individuals, 5-year-olds exhibited greater variance in ambiguity preferences compared with adults tested under similar conditions. This suggests that ambiguity aversion is absent during early childhood and emerges over the course of development. Copyright © 2017 Elsevier Inc. All rights reserved.

Solution of linear ill-posed problems using overcomplete dictionaries

OpenAIRE

Pensky, Marianna

2016-01-01

In the present paper we consider application of overcomplete dictionaries to solution of general ill-posed linear inverse problems. Construction of an adaptive optimal solution for such problems usually relies either on a singular value decomposition or representation of the solution via an orthonormal basis. The shortcoming of both approaches lies in the fact that, in many situations, neither the eigenbasis of the linear operator nor a standard orthonormal basis constitutes an appropriate co...

Off-Policy Actor-Critic Structure for Optimal Control of Unknown Systems With Disturbances.

Science.gov (United States)

Song, Ruizhuo; Lewis, Frank L; Wei, Qinglai; Zhang, Huaguang

2016-05-01

An optimal control method is developed for unknown continuous-time systems with unknown disturbances in this paper. The integral reinforcement learning (IRL) algorithm is presented to obtain the iterative control. Off-policy learning is used to allow the dynamics to be completely unknown. Neural networks are used to construct critic and action networks. It is shown that if there are unknown disturbances, off-policy IRL may not converge or may be biased. For reducing the influence of unknown disturbances, a disturbances compensation controller is added. It is proven that the weight errors are uniformly ultimately bounded based on Lyapunov techniques. Convergence of the Hamiltonian function is also proven. The simulation study demonstrates the effectiveness of the proposed optimal control method for unknown systems with disturbances.

Monitoring and risk assessment of pesticides in irrigation systems in Debra Zeit, Ethiopia.

Science.gov (United States)

Teklu, Berhan M; Adriaanse, Paulien I; Van den Brink, Paul J

2016-10-01

Since Ethiopia is going through a rapid transformation of its agricultural sector, we assessed the human health and environmental risks due to the past use of organochlorine pesticides (OCPs) as well as the risks of the current pesticide use by farmers. A monitoring programme and risk assessment was carried out for the Wedecha-Belbela irrigation system in the Debra Zeit area. The Wedecha and Belbela rivers and adjacent temporary ponds were sampled and examined for the presence of OCPs between August and October 2014, while data on the current pesticide use by small- and large-scale farmers was collected by interviews. The usage patterns were evaluated for risks of using the river or temporary ponds as source of drinking water and for risks for the aquatic ecosystems in the river and ponds with the aid of the PRIMET_Registration_Ethiopa_1.1 model. The samples were collected in five sampling periods, and results indicate that most of the 18 target OCPs were not detected above the detection limit, while g-chlordane may pose chronic risks when surface water is used as drinking water. Endosulfan and heptachlor pose risks to aquatic organisms at second-tier level, while for heptachlor-epoxide B, g-chlordane and b-BHC only risks could be determined at the first tier due to a lack of data. For all nine pesticides used by small-scale farmers the calculated acute risks to humans were low. Second tier risk assessment for the aquatic ecosystem indicated that lambda-cyhalothrin, endosulfan, profenofos, and diazinon may pose high risks. Copyright © 2016 Elsevier Ltd. All rights reserved.

Framework for Shared Drinking Water Risk Assessment.

Energy Technology Data Exchange (ETDEWEB)

Lowry, Thomas Stephen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Tidwell, Vincent C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Peplinski, William John [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mitchell, Roger [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Binning, David [AEM Corp., Herndon, VA (United States); Meszaros, Jenny [AEM Corp., Herndon, VA (United States)

2017-01-01

Central to protecting our nation's critical infrastructure is the development of methodologies for prioritizing action and supporting resource allocation decisions associated with risk-reduction initiatives. Toward this need a web-based risk assessment framework that promotes the anonymous sharing of results among water utilities is demonstrated. Anonymous sharing of results offers a number of potential advantages such as assistance in recognizing and correcting bias, identification of 'unknown, unknowns', self-assessment and benchmarking for the local utility, treatment of shared assets and/or threats across multiple utilities, and prioritization of actions beyond the scale of a single utility. The constructed framework was demonstrated for three water utilities. Demonstration results were then compared to risk assessment results developed using a different risk assessment application by a different set of analysts.

Escaping peril: perceived predation risk affects migratory propensity

DEFF Research Database (Denmark)

Hulthén, Kaj; Chapman, Ben B.; Nilsson, P. Anders

2015-01-01

Although migratory plasticity is increasingly documented, the ecological drivers of plasticity are not well understood. Predation risk can influence migratory dynamics, but whether seasonal migrants can adjust their migratory behaviour according to perceived risk is unknown. We used electronic ta......) affected timing but not propensity showing that elevated risk carried over to alter migratory behaviour in the wild. Our key finding demonstrates predator-driven migratory plasticity, highlighting the powerful role of predation risk for migratory decision-making and dynamics.......Although migratory plasticity is increasingly documented, the ecological drivers of plasticity are not well understood. Predation risk can influence migratory dynamics, but whether seasonal migrants can adjust their migratory behaviour according to perceived risk is unknown. We used electronic tags...... in their lake summer habitat and monitored individual migration to connected streams over an entire season. Individuals exposed to increased perceived direct predation risk (i.e. a live predator) showed a higher migratory propensity but no change in migratory timing, while indirect risk (i.e. roach density...

[Badminton--unknown sport].

Science.gov (United States)

Zekan-Petrinović, Lidija

2007-01-01

For a long time, badminton was considered to be only a slow and light game for children, a game that is played outdoors and is structurally undemanding.Today, it is not an unknown and unrecognised sport, especially after it was included into the Olympics Games in 1992. Badminton is one of the oldest sports in the world. It is suitable for all ages (for children and elderly equally), women and men and even handicapped persons. Beginners can start playing badminton matches early because the basics are learned quickly. As a recreational activity, badminton is very popular in Zagreb. In the last 10 years, a number of halls specialized for badminton or offering badminton as one of available sports activities have been opened in Zagreb. At present, there are over 70 professional playgrounds for training of top contestants but also for the citizens who can play recreational badminton.

Detection of viral sequence fragments of HIV-1 subfamilies yet unknown

Directory of Open Access Journals (Sweden)

Stanke Mario

2011-04-01

Full Text Available Abstract Background Methods of determining whether or not any particular HIV-1 sequence stems - completely or in part - from some unknown HIV-1 subtype are important for the design of vaccines and molecular detection systems, as well as for epidemiological monitoring. Nevertheless, a single algorithm only, the Branching Index (BI, has been developed for this task so far. Moving along the genome of a query sequence in a sliding window, the BI computes a ratio quantifying how closely the query sequence clusters with a subtype clade. In its current version, however, the BI does not provide predicted boundaries of unknown fragments. Results We have developed Unknown Subtype Finder (USF, an algorithm based on a probabilistic model, which automatically determines which parts of an input sequence originate from a subtype yet unknown. The underlying model is based on a simple profile hidden Markov model (pHMM for each known subtype and an additional pHMM for an unknown subtype. The emission probabilities of the latter are estimated using the emission frequencies of the known subtypes by means of a (position-wise probabilistic model for the emergence of new subtypes. We have applied USF to SIV and HIV-1 sequences formerly classified as having emerged from an unknown subtype. Moreover, we have evaluated its performance on artificial HIV-1 recombinants and non-recombinant HIV-1 sequences. The results have been compared with the corresponding results of the BI. Conclusions Our results demonstrate that USF is suitable for detecting segments in HIV-1 sequences stemming from yet unknown subtypes. Comparing USF with the BI shows that our algorithm performs as good as the BI or better.

A combined vision-inertial fusion approach for 6-DoF object pose estimation

Science.gov (United States)

Li, Juan; Bernardos, Ana M.; Tarrío, Paula; Casar, José R.

2015-02-01

The estimation of the 3D position and orientation of moving objects (`pose' estimation) is a critical process for many applications in robotics, computer vision or mobile services. Although major research efforts have been carried out to design accurate, fast and robust indoor pose estimation systems, it remains as an open challenge to provide a low-cost, easy to deploy and reliable solution. Addressing this issue, this paper describes a hybrid approach for 6 degrees of freedom (6-DoF) pose estimation that fuses acceleration data and stereo vision to overcome the respective weaknesses of single technology approaches. The system relies on COTS technologies (standard webcams, accelerometers) and printable colored markers. It uses a set of infrastructure cameras, located to have the object to be tracked visible most of the operation time; the target object has to include an embedded accelerometer and be tagged with a fiducial marker. This simple marker has been designed for easy detection and segmentation and it may be adapted to different service scenarios (in shape and colors). Experimental results show that the proposed system provides high accuracy, while satisfactorily dealing with the real-time constraints.

The Pose Estimation of Mobile Robot Based on Improved Point Cloud Registration

Directory of Open Access Journals (Sweden)

Yanzi Miao

2016-03-01

Full Text Available Due to GPS restrictions, an inertial sensor is usually used to estimate the location of indoor mobile robots. However, it is difficult to achieve high-accuracy localization and control by inertial sensors alone. In this paper, a new method is proposed to estimate an indoor mobile robot pose with six degrees of freedom based on an improved 3D-Normal Distributions Transform algorithm (3D-NDT. First, point cloud data are captured by a Kinect sensor and segmented according to the distance to the robot. After the segmentation, the input point cloud data are processed by the Approximate Voxel Grid Filter algorithm in different sized voxel grids. Second, the initial registration and precise registration are performed respectively according to the distance to the sensor. The most distant point cloud data use the 3D-Normal Distributions Transform algorithm (3D-NDT with large-sized voxel grids for initial registration, based on the transformation matrix from the odometry method. The closest point cloud data use the 3D-NDT algorithm with small-sized voxel grids for precise registration. After the registrations above, a final transformation matrix is obtained and coordinated. Based on this transformation matrix, the pose estimation problem of the indoor mobile robot is solved. Test results show that this method can obtain accurate robot pose estimation and has better robustness.

Maternal physiological dysregulation while parenting poses risk for infant attachment disorganization and behavior problems.

Science.gov (United States)

Leerkes, Esther M; Su, Jinni; Calkins, Susan D; O'Brien, Marion; Supple, Andrew J

2017-02-01

The extent to which indices of maternal physiological arousal (skin conductance augmentation) and regulation (vagal withdrawal) while parenting predict infant attachment disorganization and behavior problems directly or indirectly via maternal sensitivity was examined in a sample of 259 mothers and their infants. Two covariates, maternal self-reported emotional risk and Adult Attachment Interview attachment coherence were assessed prenatally. Mothers' physiological arousal and regulation were measured during parenting tasks when infants were 6 months old. Maternal sensitivity was observed during distress-eliciting tasks when infants were 6 and 14 months old, and an average sensitivity score was calculated. Attachment disorganization was observed during the Strange Situation when infants were 14 months old, and mothers reported on infants' behavior problems when infants were 27 months old. Over and above covariates, mothers' arousal and regulation while parenting interacted to predict infant attachment disorganization and behavior problems such that maternal arousal was associated with higher attachment disorganization and behavior problems when maternal regulation was low but not when maternal regulation was high. This effect was direct and not explained by maternal sensitivity. The results suggest that maternal physiological dysregulation while parenting places infants at risk for psychopathology.

Surgical fiducial segmentation and tracking for pose estimation based on ultrasound B-mode images.

Science.gov (United States)

Lei Chen; Kuo, Nathanael; Aalamifar, Fereshteh; Narrow, David; Coon, Devin; Prince, Jerry; Boctor, Emad M

2016-08-01

Doppler ultrasound is a non-invasive diagnostic tool for the quantitative measurement of blood flow. However, given that it provides velocity data that is dependent on the location and angle of measurement, repeat measurements to detect problems over time may require an expert to return to the same location. We therefore developed an image-guidance system based on ultrasound B-mode images that enables an inexperienced user to position the ultrasound probe at the same site repeatedly in order to acquire a comparable time series of Doppler readings. The system utilizes a bioresorbable fiducial and complementing software composed of the fiducial detection, key points tracking, probe pose estimation, and graphical user interface (GUI) modules. The fiducial is an echogenic marker that is implanted at the surgical site and can be detected and tracked during ultrasound B-mode screening. The key points on the marker can next be used to determine the pose of the ultrasound probe with respect to the marker. The 3D representation of the probe with its position and orientation are then displayed in the GUI for the user guidance. The fiducial detection has been tested on the data sets collected from three animal studies. The pose estimation algorithm was validated by five data sets collected by a UR5 robot. We tested the system on a plastisol phantom and showed that it can detect and track the fiducial marker while displaying the probe pose in real-time.

Marker detection evaluation by phantom and cadaver experiments for C-arm pose estimation pattern

Science.gov (United States)

Steger, Teena; Hoßbach, Martin; Wesarg, Stefan

2013-03-01

C-arm fluoroscopy is used for guidance during several clinical exams, e.g. in bronchoscopy to locate the bronchoscope inside the airways. Unfortunately, these images provide only 2D information. However, if the C-arm pose is known, it can be used to overlay the intrainterventional fluoroscopy images with 3D visualizations of airways, acquired from preinterventional CT images. Thus, the physician's view is enhanced and localization of the instrument at the correct position inside the bronchial tree is facilitated. We present a novel method for C-arm pose estimation introducing a marker-based pattern, which is placed on the patient table. The steel markers form a pattern, allowing to deduce the C-arm pose by use of the projective invariant cross-ratio. Simulations show that the C-arm pose estimation is reliable and accurate for translations inside an imaging area of 30 cm x 50 cm and rotations up to 30°. Mean error values are 0.33 mm in 3D space and 0.48 px in the 2D imaging plane. First tests on C-arm images resulted in similarly compelling accuracy values and high reliability in an imaging area of 30 cm x 42.5 cm. Even in the presence of interfering structures, tested both with anatomy phantoms and a turkey cadaver, high success rates over 90% and fully satisfying execution times below 4 sec for 1024 px × 1024 px images could be achieved.

Psychological profile: the problem of modeling the unknown criminal personality

Directory of Open Access Journals (Sweden)

Г. М. Гетьман

2013-10-01

Full Text Available The article investigates the problem of modeling an unknown person in the preparation of criminal psychological profile. Some approaches to the concept of "psychological profile" and "psychological portrait", in particular the proposed delineation of these terms. We consider the system steps in the development of the psychological profile of an unknown perpetrator.

Multifocal chronic osteomyelitis of unknown etiology

International Nuclear Information System (INIS)

Kozlowski, K.; Masel, J.; Harbison, S.; Yu, J.; Royal Brisbane Children Hospital; Regional Hospital Bowral

1983-01-01

Five cases of chronic, inflammatory, multifocal bone lesions of unknown etiology are reported. Although bone biopsy confirmed osteomyelitis in each case in none of them were organisms found inspite of an extensive work up. Different clinical course of the disease reflects different aetiology in respective cases. These cases present changing aspects of osteomyelitis emerging since introduction of antibiotics. (orig.)

Bayesian source term determination with unknown covariance of measurements

Science.gov (United States)

Belal, Alkomiet; Tichý, Ondřej; Šmídl, Václav

2017-04-01

Determination of a source term of release of a hazardous material into the atmosphere is a very important task for emergency response. We are concerned with the problem of estimation of the source term in the conventional linear inverse problem, y = Mx, where the relationship between the vector of observations y is described using the source-receptor-sensitivity (SRS) matrix M and the unknown source term x. Since the system is typically ill-conditioned, the problem is recast as an optimization problem minR,B(y - Mx)TR-1(y - Mx) + xTB-1x. The first term minimizes the error of the measurements with covariance matrix R, and the second term is a regularization of the source term. There are different types of regularization arising for different choices of matrices R and B, for example, Tikhonov regularization assumes covariance matrix B as the identity matrix multiplied by scalar parameter. In this contribution, we adopt a Bayesian approach to make inference on the unknown source term x as well as unknown R and B. We assume prior on x to be a Gaussian with zero mean and unknown diagonal covariance matrix B. The covariance matrix of the likelihood R is also unknown. We consider two potential choices of the structure of the matrix R. First is the diagonal matrix and the second is a locally correlated structure using information on topology of the measuring network. Since the inference of the model is intractable, iterative variational Bayes algorithm is used for simultaneous estimation of all model parameters. The practical usefulness of our contribution is demonstrated on an application of the resulting algorithm to real data from the European Tracer Experiment (ETEX). This research is supported by EEA/Norwegian Financial Mechanism under project MSMT-28477/2014 Source-Term Determination of Radionuclide Releases by Inverse Atmospheric Dispersion Modelling (STRADI).

Recurrent severe invasive pneumococcal disease in an adult with previously unknown hyposplenia

DEFF Research Database (Denmark)

Ballegaard, Vibe C; Schejbel, Lone; Hoffmann, Steen

2015-01-01

was found. Despite immunization against S. pneumoniae and measurement of what was interpreted as protective levels of serotype-specific IgG antibodies after vaccination, the patient suffered from a third episode of IPD. CONCLUSIONS: Individuals with predisposing medical conditions or a history of severe......BACKGROUND: The risk of life-threatening and invasive infections with encapsulated bacteria is increased in patients with hyposplenia or asplenia. We report a case of recurrent invasive pneumococcal meningitis in a woman with previous unknown hyposplenia. She was vaccinated after the first episode...... of meningitis and developed sufficient levels of pneumococcal antibodies. The pneumococcal strains isolated were serotype 7 F and 17 F. To our knowledge, there has been no previously reported case of recurrent invasive pneumococcal disease in a pneumococcal vaccinated adult with hyposplenia and apparently...

Comparison of models used for ecological risk assessment and human health risk assessment

International Nuclear Information System (INIS)

Ryti, R.T.; Gallegos, A.F.

1994-01-01

Models are used to derive action levels for site screening, or to estimate potential ecological or human health risks posed by potentially hazardous sites. At the Los Alamos National Laboratory (LANL), which is RCRA-regulated, the human-health screening action levels are based on hazardous constituents described in RCRA Subpart S and RESRAD-derived soil guidelines (based on 10 mRem/year) for radiological constituents. Also, an ecological risk screening model was developed for a former firing site, where the primary constituents include depleted uranium, beryllium and lead. Sites that fail the screening models are evaluated with site-specific human risk assessment (using RESRAD and other approaches) and a detailed ecological effect model (ECOTRAN). ECOTRAN is based on pharmacokinetics transport modeling within a multitrophic-level biological-growth dynamics model. ECOTRAN provides detailed temporal records of contaminant concentrations in biota, and annual averages of these body burdens are compared to equivalent site-specific runs of the RESRAD model. The results show that thoughtful interpretation of the results of these models must be applied before they can be used for evaluation of current risk posed by sites and the benefits of various remedial options. This presentation compares the concentrations of biological media in the RESRAD screening runs to the concentrations in ecological endpoints predicted by the ecological screening model. The assumptions and limitations of these screening models and the decision process where these are screening models are applied are discussed

Celiac Disease Presenting as Fever of Unknown Origin

Directory of Open Access Journals (Sweden)

Megan J. Cooney

2013-01-01

Full Text Available Celiac disease (CD is a common autoimmune enteropathy that occurs, in affected individuals, with exposure to gluten in the diet and improves with removal of dietary gluten. Although CD is readily considered in patients with classical presentations of the disease, atypical manifestations may be the only presenting symptoms. We present a case of CD in a 16-year-old female presenting as fever of unknown origin, which has not been reported previously. The postulated mechanism for fever in CD and the importance of clinicians having a low threshold for considering CD in the differential diagnosis of fever of unknown origin and other enigmatic clinical presentations is discussed.

Effects of the Problem-Posing Approach on Students' Problem Solving Skills and Metacognitive Awareness in Science Education

Science.gov (United States)

Akben, Nimet

2018-05-01

The interrelationship between mathematics and science education has frequently been emphasized, and common goals and approaches have often been adopted between disciplines. Improving students' problem-solving skills in mathematics and science education has always been given special attention; however, the problem-posing approach which plays a key role in mathematics education has not been commonly utilized in science education. As a result, the purpose of this study was to better determine the effects of the problem-posing approach on students' problem-solving skills and metacognitive awareness in science education. This was a quasi-experimental based study conducted with 61 chemistry and 40 physics students; a problem-solving inventory and a metacognitive awareness inventory were administered to participants both as a pre-test and a post-test. During the 2017-2018 academic year, problem-solving activities based on the problem-posing approach were performed with the participating students during their senior year in various university chemistry and physics departments throughout the Republic of Turkey. The study results suggested that structured, semi-structured, and free problem-posing activities improve students' problem-solving skills and metacognitive awareness. These findings indicated not only the usefulness of integrating problem-posing activities into science education programs but also the need for further research into this question.

Method for Assessing the Integrated Risk of Soil Pollution in Industrial and Mining Gathering Areas

Science.gov (United States)

Guan, Yang; Shao, Chaofeng; Gu, Qingbao; Ju, Meiting; Zhang, Qian

2015-01-01

Industrial and mining activities are recognized as major sources of soil pollution. This study proposes an index system for evaluating the inherent risk level of polluting factories and introduces an integrated risk assessment method based on human health risk. As a case study, the health risk, polluting factories and integrated risks were analyzed in a typical industrial and mining gathering area in China, namely, Binhai New Area. The spatial distribution of the risk level was determined using a Geographic Information System. The results confirmed the following: (1) Human health risk in the study area is moderate to extreme, with heavy metals posing the greatest threat; (2) Polluting factories pose a moderate to extreme inherent risk in the study area. Such factories are concentrated in industrial and urban areas, but are irregularly distributed and also occupy agricultural land, showing a lack of proper planning and management; (3) The integrated risks of soil are moderate to high in the study area. PMID:26580644

Method for Assessing the Integrated Risk of Soil Pollution in Industrial and Mining Gathering Areas.

Science.gov (United States)

Guan, Yang; Shao, Chaofeng; Gu, Qingbao; Ju, Meiting; Zhang, Qian

2015-11-13

Industrial and mining activities are recognized as major sources of soil pollution. This study proposes an index system for evaluating the inherent risk level of polluting factories and introduces an integrated risk assessment method based on human health risk. As a case study, the health risk, polluting factories and integrated risks were analyzed in a typical industrial and mining gathering area in China, namely, Binhai New Area. The spatial distribution of the risk level was determined using a Geographic Information System. The results confirmed the following: (1) Human health risk in the study area is moderate to extreme, with heavy metals posing the greatest threat; (2) Polluting factories pose a moderate to extreme inherent risk in the study area. Such factories are concentrated in industrial and urban areas, but are irregularly distributed and also occupy agricultural land, showing a lack of proper planning and management; (3) The integrated risks of soil are moderate to high in the study area.

Improving head and body pose estimation through semi-supervised manifold alignment

KAUST Repository

Heili, Alexandre; Varadarajan, Jagannadan; Ghanem, Bernard; Ahuja, Narendra; Odobez, Jean-Marc

2014-01-01

structure of the features in the train and target data and the need to align them were not explored despite the fact that the pose features between two datasets may vary according to the scene, e.g. due to different camera point of view or perspective

Fast grasping of unknown objects using principal component analysis

Science.gov (United States)

Lei, Qujiang; Chen, Guangming; Wisse, Martijn

2017-09-01

Fast grasping of unknown objects has crucial impact on the efficiency of robot manipulation especially subjected to unfamiliar environments. In order to accelerate grasping speed of unknown objects, principal component analysis is utilized to direct the grasping process. In particular, a single-view partial point cloud is constructed and grasp candidates are allocated along the principal axis. Force balance optimization is employed to analyze possible graspable areas. The obtained graspable area with the minimal resultant force is the best zone for the final grasping execution. It is shown that an unknown object can be more quickly grasped provided that the component analysis principle axis is determined using single-view partial point cloud. To cope with the grasp uncertainty, robot motion is assisted to obtain a new viewpoint. Virtual exploration and experimental tests are carried out to verify this fast gasping algorithm. Both simulation and experimental tests demonstrated excellent performances based on the results of grasping a series of unknown objects. To minimize the grasping uncertainty, the merits of the robot hardware with two 3D cameras can be utilized to suffice the partial point cloud. As a result of utilizing the robot hardware, the grasping reliance is highly enhanced. Therefore, this research demonstrates practical significance for increasing grasping speed and thus increasing robot efficiency under unpredictable environments.

Limit lines for risk

International Nuclear Information System (INIS)

Cox, D.C.; Baybutt, P.

1982-01-01

Approaches to the regulation of risk from technological systems, such as nuclear power plants or chemical process plants, in which potential accidents may result in a broad range of adverse consequences must take into account several different aspects of risk. These include overall or average risk, accidents posing high relative risks, the rate at which accident probability decreases with increasing accident consequences, and the impact of high frequency, low consequence accidents. A hypothetical complementary cumulative distribution function (CCDF), with appropriately chosen parametric form, meets all these requirements. The Farmer limit line, by contrast, places limits on the risks due to individual accident sequences, and cannot adequately account for overall risk. This reduces its usefulness as a regulatory tool. In practice, the CCDF is used in the Canadian nuclear licensing process, while the Farmer limit line approach, supplemented by separate qualitative limits on overall risk, is employed in the United Kingdom

78 FR 25440 - Request for Information and Citations on Methods for Cumulative Risk Assessment

Science.gov (United States)

2013-05-01

... Citations on Methods for Cumulative Risk Assessment AGENCY: Office of the Science Advisor, Environmental... influence exposures, dose-response or risk/hazard posed by environmental contaminant exposures, and methods... who wish to receive further information about submitting information on methods for cumulative risk...

Does intake of trace elements through urban gardening in Copenhagen pose a risk to human health?

DEFF Research Database (Denmark)

Warming, Marlies; Hansen, Mette G.; Holm, Peter E.

2015-01-01

This study investigates the potential health risk from urban gardening. The concentrations of the trace elements arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), nickel (Ni), and zinc (Zn) in five common garden crops from three garden sites in Copenhagen were measured. Concentra......This study investigates the potential health risk from urban gardening. The concentrations of the trace elements arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), nickel (Ni), and zinc (Zn) in five common garden crops from three garden sites in Copenhagen were measured...

Does intake of trace elements through urban gardening in Copenhagen pose a risk to human health?

Science.gov (United States)

Warming, Marlies; Hansen, Mette G; Holm, Peter E; Magid, Jakob; Hansen, Thomas H; Trapp, Stefan

2015-07-01

This study investigates the potential health risk from urban gardening. The concentrations of the trace elements arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), nickel (Ni), and zinc (Zn) in five common garden crops from three garden sites in Copenhagen were measured. Concentrations (mg/kg dw) of As were 0.002-0.21, Cd 0.03-0.25, Cr gardening in Copenhagen. Exposure to Pb contaminated sites may lead to unacceptable risk not caused by vegetable consumption but by unintentional soil ingestion. Copyright © 2015 Elsevier Ltd. All rights reserved.

Augmenting the Deliberative Method for Ranking Risks.

Science.gov (United States)

Susel, Irving; Lasley, Trace; Montezemolo, Mark; Piper, Joel

2016-01-01

The Department of Homeland Security (DHS) characterized and prioritized the physical cross-border threats and hazards to the nation stemming from terrorism, market-driven illicit flows of people and goods (illegal immigration, narcotics, funds, counterfeits, and weaponry), and other nonmarket concerns (movement of diseases, pests, and invasive species). These threats and hazards pose a wide diversity of consequences with very different combinations of magnitudes and likelihoods, making it very challenging to prioritize them. This article presents the approach that was used at DHS to arrive at a consensus regarding the threats and hazards that stand out from the rest based on the overall risk they pose. Due to time constraints for the decision analysis, it was not feasible to apply multiattribute methodologies like multiattribute utility theory or the analytic hierarchy process. Using a holistic approach was considered, such as the deliberative method for ranking risks first published in this journal. However, an ordinal ranking alone does not indicate relative or absolute magnitude differences among the risks. Therefore, the use of the deliberative method for ranking risks is not sufficient for deciding whether there is a material difference between the top-ranked and bottom-ranked risks, let alone deciding what the stand-out risks are. To address this limitation of ordinal rankings, the deliberative method for ranking risks was augmented by adding an additional step to transform the ordinal ranking into a ratio scale ranking. This additional step enabled the selection of stand-out risks to help prioritize further analysis. © 2015 Society for Risk Analysis.

Relative Pose Estimation Algorithm with Gyroscope Sensor

Directory of Open Access Journals (Sweden)

Shanshan Wei

2016-01-01

Full Text Available This paper proposes a novel vision and inertial fusion algorithm S2fM (Simplified Structure from Motion for camera relative pose estimation. Different from current existing algorithms, our algorithm estimates rotation parameter and translation parameter separately. S2fM employs gyroscopes to estimate camera rotation parameter, which is later fused with the image data to estimate camera translation parameter. Our contributions are in two aspects. (1 Under the circumstance that no inertial sensor can estimate accurately enough translation parameter, we propose a translation estimation algorithm by fusing gyroscope sensor and image data. (2 Our S2fM algorithm is efficient and suitable for smart devices. Experimental results validate efficiency of the proposed S2fM algorithm.

A metasynthesis of risk perception in women with high risk pregnancies.

Science.gov (United States)

Lee, Suzanne; Ayers, Susan; Holden, Des

2014-04-01

risk perception in women with high risk pregnancies affects their decisions about perinatal care and is of interest to anyone involved in the care of pregnant women. This paper provides a metasynthesis of qualitative studies of risk perception in women with high risk pregnancies. a systematic search of eight electronic databases was conducted. Additional papers were obtained through searching references of identified articles. Six studies were identified that reported qualitative research into risk perception in relation to high risk pregnancy. A metasynthesis was developed to describe and interpret the studies. the synthesis resulted in the identification of five themes: determinants of risk perception; not seeing it the way others do; normality versus risk; if the infant is ok, I׳m ok; managing risk. this metasynthesis suggests women at high risk during pregnancy use multiple sources of information to determine their risk status. It shows women are aware of the risks posed by their pregnancies but do not perceive risk in the same way as healthcare professionals. They will take steps to ensure the health of themselves and their infants but these may not include following all medical recommendations. Copyright © 2013 Elsevier Ltd. All rights reserved.

Neural correlates of value, risk, and risk aversion contributing to decision making under risk.

Science.gov (United States)

Christopoulos, George I; Tobler, Philippe N; Bossaerts, Peter; Dolan, Raymond J; Schultz, Wolfram

2009-10-07

Decision making under risk is central to human behavior. Economic decision theory suggests that value, risk, and risk aversion influence choice behavior. Although previous studies identified neural correlates of decision parameters, the contribution of these correlates to actual choices is unknown. In two different experiments, participants chose between risky and safe options. We identified discrete blood oxygen level-dependent (BOLD) correlates of value and risk in the ventral striatum and anterior cingulate, respectively. Notably, increasing inferior frontal gyrus activity to low risk and safe options correlated with higher risk aversion. Importantly, the combination of these BOLD responses effectively decoded the behavioral choice. Striatal value and cingulate risk responses increased the probability of a risky choice, whereas inferior frontal gyrus responses showed the inverse relationship. These findings suggest that the BOLD correlates of decision factors are appropriate for an ideal observer to detect behavioral choices. More generally, these biological data contribute to the validity of the theoretical decision parameters for actual decisions under risk.

Analysis of Problems Posed by Sixth-Grade Middle School Students for the Addition of Fractions in Terms of Semantic Structures

Science.gov (United States)

Kar, Tugrul

2015-01-01

This study aimed to investigate how the semantic structures of problems posed by sixth-grade middle school students for the addition of fractions affect their problem-posing performance. The students were presented with symbolic operations involving the addition of fractions and asked to pose two different problems related to daily-life situations…

SU-G-JeP3-03: Effect of Robot Pose On Beam Blocking for Ultrasound Guided SBRT of the Prostate

Energy Technology Data Exchange (ETDEWEB)

Gerlach, S; Schlaefer, A [Hamburg University of Technology, Hamburg (Germany); Kuhlemann, I; Ernst, F [Universitaet zu Luebeck, Luebeck (Germany); Fuerweger, C [European Cyberknife Center Munich, Munich (Germany)

2016-06-15

Purpose: Ultrasound presents a fast, volumetric image modality for real-time tracking of abdominal organ motion. How-ever, ultrasound transducer placement during radiation therapy is challenging. Recently, approaches using robotic arms for intra-treatment ultrasound imaging have been proposed. Good and reliable imaging requires placing the transducer close to the PTV. We studied the effect of a seven degrees of freedom robot on the fea-sible beam directions. Methods: For five CyberKnife prostate treatment plans we established viewports for the transducer, i.e., points on the patient surface with a soft tissue view towards the PTV. Choosing a feasible transducer pose and using the kinematic redundancy of the KUKA LBR iiwa robot, we considered three robot poses. Poses 1 to 3 had the elbow point anterior, superior, and inferior, respectively. For each pose and each beam starting point, the pro-jections of robot and PTV were computed. We added a 20 mm margin accounting for organ / beam motion. The number of nodes for which the PTV was partially of fully blocked were established. Moreover, the cumula-tive overlap for each of the poses and the minimum overlap over all poses were computed. Results: The fully and partially blocked nodes ranged from 12% to 20% and 13% to 27%, respectively. Typically, pose 3 caused the fewest blocked nodes. The cumulative overlap ranged from 19% to 29%. Taking the minimum overlap, i.e., considering moving the robot’s elbow while maintaining the transducer pose, the cumulative over-lap was reduced to 16% to 18% and was 3% to 6% lower than for the best individual pose. Conclusion: Our results indicate that it is possible to identify feasible ultrasound transducer poses and to use the kinematic redundancy of a 7 DOF robot to minimize the impact of the imaging subsystem on the feasible beam directions for ultrasound guided and motion compensated SBRT. Research partially funded by DFG grants ER 817/1-1 and SCHL 1844/3-1.

SU-G-JeP3-03: Effect of Robot Pose On Beam Blocking for Ultrasound Guided SBRT of the Prostate

International Nuclear Information System (INIS)

Gerlach, S; Schlaefer, A; Kuhlemann, I; Ernst, F; Fuerweger, C

2016-01-01

Purpose: Ultrasound presents a fast, volumetric image modality for real-time tracking of abdominal organ motion. How-ever, ultrasound transducer placement during radiation therapy is challenging. Recently, approaches using robotic arms for intra-treatment ultrasound imaging have been proposed. Good and reliable imaging requires placing the transducer close to the PTV. We studied the effect of a seven degrees of freedom robot on the fea-sible beam directions. Methods: For five CyberKnife prostate treatment plans we established viewports for the transducer, i.e., points on the patient surface with a soft tissue view towards the PTV. Choosing a feasible transducer pose and using the kinematic redundancy of the KUKA LBR iiwa robot, we considered three robot poses. Poses 1 to 3 had the elbow point anterior, superior, and inferior, respectively. For each pose and each beam starting point, the pro-jections of robot and PTV were computed. We added a 20 mm margin accounting for organ / beam motion. The number of nodes for which the PTV was partially of fully blocked were established. Moreover, the cumula-tive overlap for each of the poses and the minimum overlap over all poses were computed. Results: The fully and partially blocked nodes ranged from 12% to 20% and 13% to 27%, respectively. Typically, pose 3 caused the fewest blocked nodes. The cumulative overlap ranged from 19% to 29%. Taking the minimum overlap, i.e., considering moving the robot’s elbow while maintaining the transducer pose, the cumulative over-lap was reduced to 16% to 18% and was 3% to 6% lower than for the best individual pose. Conclusion: Our results indicate that it is possible to identify feasible ultrasound transducer poses and to use the kinematic redundancy of a 7 DOF robot to minimize the impact of the imaging subsystem on the feasible beam directions for ultrasound guided and motion compensated SBRT. Research partially funded by DFG grants ER 817/1-1 and SCHL 1844/3-1.

Quantum key distribution with an unknown and untrusted source

Science.gov (United States)

Zhao, Yi; Qi, Bing; Lo, Hoi-Kwong

2009-03-01

The security of a standard bi-directional ``plug & play'' quantum key distribution (QKD) system has been an open question for a long time. This is mainly because its source is equivalently controlled by an eavesdropper, which means the source is unknown and untrusted. Qualitative discussion on this subject has been made previously. In this paper, we present the first quantitative security analysis on a general class of QKD protocols whose sources are unknown and untrusted. The securities of standard BB84 protocol, weak+vacuum decoy state protocol, and one-decoy decoy state protocol, with unknown and untrusted sources are rigorously proved. We derive rigorous lower bounds to the secure key generation rates of the above three protocols. Our numerical simulation results show that QKD with an untrusted source gives a key generation rate that is close to that with a trusted source. Our work is published in [1]. [4pt] [1] Y. Zhao, B. Qi, and H.-K. Lo, Phys. Rev. A, 77:052327 (2008).

Grasping Unknown Objects in an Early Cognitive Vision System

DEFF Research Database (Denmark)

Popovic, Mila

2011-01-01

Grasping of unknown objects presents an important and challenging part of robot manipulation. The growing area of service robotics depends upon the ability of robots to autonomously grasp and manipulate a wide range of objects in everyday environments. Simple, non task-specific grasps of unknown ...... and comparing vision-based grasping methods, and the creation of algorithms for bootstrapping a process of acquiring world understanding for artificial cognitive agents....... presents a system for robotic grasping of unknown objects us- ing stereo vision. Grasps are defined based on contour and surface information provided by the Early Cognitive Vision System, that organizes visual informa- tion into a biologically motivated hierarchical representation. The contributions...... of the thesis are: the extension of the Early Cognitive Vision representation with a new type of feature hierarchy in the texture domain, the definition and evaluation of contour based grasping methods, the definition and evaluation of surface based grasping methods, the definition of a benchmark for testing...

Laser Remediation of Threats Posed by Small Orbital Debris

Science.gov (United States)

Fork, Richard L.; Rogers, Jan R.; Hovater, Mary A.

2012-01-01

The continually increasing amount of orbital debris in near Earth space poses an increasing challenge to space situational awareness. Recent collisions of spacecraft caused abrupt increases in the density of both large and small debris in near Earth space. An especially challenging class of threats is that due to the increasing density of small (1 mm to 10 cm dimension) orbital debris. This small debris poses a serious threat since: (1) The high velocity enables even millimeter dimension debris to cause serious damage to vulnerable areas of space assets, e.g., detector windows; (2) The small size and large number of debris elements prevent adequate detection and cataloguing. We have identified solutions to this threat in the form of novel laser systems and novel ways of using these laser systems. While implementation of the solutions we identify is challenging we find approaches offering threat mitigation within time frames and at costs of practical interest. We base our analysis on the unique combination of coherent light specifically structured in both space and time and applied in novel ways entirely within the vacuum of space to deorbiting small debris. We compare and contrast laser based small debris removal strategies using ground based laser systems with strategies using space based laser systems. We find laser systems located and used entirely within space offer essential and decisive advantages over groundbased laser systems.

Towards real-time body pose estimation for presenters in meeting environments

NARCIS (Netherlands)

Poppe, Ronald Walter; Heylen, Dirk K.J.; Nijholt, Antinus; Poel, Mannes

2005-01-01

This paper describes a computer vision-based approach to body pose estimation. The algorithm can be executed in real-time and processes low resolution, monocular image sequences. A silhouette is extracted and matched against a projection of a 16 DOF human body model. In addition, skin color is used

Novelty Detection for Interactive Pose Recognition by a Social Robot

Directory of Open Access Journals (Sweden)

Victor Gonzalez-Pacheco

2015-04-01

Full Text Available Active robot learners take an active role in their own learning by making queries to their human teachers when they receive new data. However, not every received input is useful for the robot, and asking for non-informative inputs or asking too many questions might worsen the user's perception of the robot. We present a novelty detection system that enables a robot to ask labels for new stimuli only when they seem both novel and interesting. Our system separates the decision process into two steps: first, it discriminates novel from known stimuli, and second, it estimates if these stimuli are likely to happen again. Our approach uses the notion of curiosity, which controls the eagerness with which the robot asks questions to the user. We evaluate our approach in the domain of pose learning by training our robot with a set of pointing poses able to detect up to 84%, 79%, and 78% of the observed novelties in three different experiments. Our approach enables robots to keep learning continuously, even after training is finished. The introduction of the curiosity parameter allows tuning, for the conditions in which the robot should want to learn more.

Probabilistic Mapping of Human Visual Attention from Head Pose Estimation

Directory of Open Access Journals (Sweden)

Andrea Veronese

2017-10-01

Full Text Available Effective interaction between a human and a robot requires the bidirectional perception and interpretation of actions and behavior. While actions can be identified as a directly observable activity, this might not be sufficient to deduce actions in a scene. For example, orienting our face toward a book might suggest the action toward “reading.” For a human observer, this deduction requires the direction of gaze, the object identified as a book and the intersection between gaze and book. With this in mind, we aim to estimate and map human visual attention as directed to a scene, and assess how this relates to the detection of objects and their related actions. In particular, we consider human head pose as measurement to infer the attention of a human engaged in a task and study which prior knowledge should be included in such a detection system. In a user study, we show the successful detection of attention to objects in a typical office task scenario (i.e., reading, working with a computer, studying an object. Our system requires a single external RGB camera for head pose measurements and a pre-recorded 3D point cloud of the environment.

Camera-pose estimation via projective Newton optimization on the manifold.

Science.gov (United States)

Sarkis, Michel; Diepold, Klaus

2012-04-01

Determining the pose of a moving camera is an important task in computer vision. In this paper, we derive a projective Newton algorithm on the manifold to refine the pose estimate of a camera. The main idea is to benefit from the fact that the 3-D rigid motion is described by the special Euclidean group, which is a Riemannian manifold. The latter is equipped with a tangent space defined by the corresponding Lie algebra. This enables us to compute the optimization direction, i.e., the gradient and the Hessian, at each iteration of the projective Newton scheme on the tangent space of the manifold. Then, the motion is updated by projecting back the variables on the manifold itself. We also derive another version of the algorithm that employs homeomorphic parameterization to the special Euclidean group. We test the algorithm on several simulated and real image data sets. Compared with the standard Newton minimization scheme, we are now able to obtain the full numerical formula of the Hessian with a 60% decrease in computational complexity. Compared with Levenberg-Marquardt, the results obtained are more accurate while having a rather similar complexity.

18F-FDG-PET/CT in fever of unknown origin

DEFF Research Database (Denmark)

Middelbo Buch-Olsen, Karen; Andersen, Rikke V; Hess, Søren

2014-01-01

OBJECTIVE: Fever of unknown origin continues to be a diagnostic challenge for clinicians. The aim of this study was to confirm whether (18)F-fluorodeoxyglucose ((18)F-FDG)-PET/computed tomography (CT) is a helpful tool in patients suffering from this condition. PATIENTS AND METHODS: Fifty......-seven patients with fever of unknown origin were examined with (18)F-FDG-PET/CT as part of their diagnostic workup at the clinicians' discretion. The medical records were read retrospectively to establish the final diagnosis and evaluate the degree to which PET/CT contributed to the diagnosis. RESULTS......-FDG-PET/CT is a useful tool in the investigation of fever of unknown origin; it can reduce patient inconvenience and possibly costs to society if used earlier in the diagnostic process....

78 FR 66010 - Draft Risk Profile on Pathogens and Filth in Spices; Availability

Science.gov (United States)

2013-11-04

...] Draft Risk Profile on Pathogens and Filth in Spices; Availability AGENCY: Food and Drug Administration... availability of a draft risk profile entitled ``FDA Draft Risk Profile: Pathogens and Filth in Spices'' (draft... posed by consumption of spices in the United States by identifying the most commonly occurring microbial...

Problem posing as a didactic resource in formal mathematics courses to train future secondary school mathematics teachers

Directory of Open Access Journals (Sweden)

Lorena Salazar Solórzano

2015-06-01

Full Text Available Beginning university training programs must focus on different competencies for mathematics teachers, i.e., not only on solving problems, but also on posing them and analyzing the mathematical activity. This paper reports the results of an exploratory study conducted with future secondary school mathematics teachers on the introduction of problem-posing tasks in formal mathematics courses, specifically in abstract algebra and real analysis courses. Evidence was found that training which includes problem-posing tasks has a positive impact on the students’ understanding of definitions, theorems and exercises within formal mathematics, as well as on their competency in reflecting on the mathematical activity. 

Soft tissue navigation for laparoscopic prostatectomy: evaluation of camera pose estimation for enhanced visualization

Science.gov (United States)

Baumhauer, M.; Simpfendörfer, T.; Schwarz, R.; Seitel, M.; Müller-Stich, B. P.; Gutt, C. N.; Rassweiler, J.; Meinzer, H.-P.; Wolf, I.

2007-03-01

We introduce a novel navigation system to support minimally invasive prostate surgery. The system utilizes transrectal ultrasonography (TRUS) and needle-shaped navigation aids to visualize hidden structures via Augmented Reality. During the intervention, the navigation aids are segmented once from a 3D TRUS dataset and subsequently tracked by the endoscope camera. Camera Pose Estimation methods directly determine position and orientation of the camera in relation to the navigation aids. Accordingly, our system does not require any external tracking device for registration of endoscope camera and ultrasonography probe. In addition to a preoperative planning step in which the navigation targets are defined, the procedure consists of two main steps which are carried out during the intervention: First, the preoperatively prepared planning data is registered with an intraoperatively acquired 3D TRUS dataset and the segmented navigation aids. Second, the navigation aids are continuously tracked by the endoscope camera. The camera's pose can thereby be derived and relevant medical structures can be superimposed on the video image. This paper focuses on the latter step. We have implemented several promising real-time algorithms and incorporated them into the Open Source Toolkit MITK (www.mitk.org). Furthermore, we have evaluated them for minimally invasive surgery (MIS) navigation scenarios. For this purpose, a virtual evaluation environment has been developed, which allows for the simulation of navigation targets and navigation aids, including their measurement errors. Besides evaluating the accuracy of the computed pose, we have analyzed the impact of an inaccurate pose and the resulting displacement of navigation targets in Augmented Reality.

Sensing Strategies for Disambiguating among Multiple Objects in Known Poses.

Science.gov (United States)

1985-08-01

ELEMENT. PROIECT. TASK Artificial Inteligence Laboratory AE OKUI UBR 545 Technology Square Cambridge, MA 021.39 11. CONTROLLING OFFICE NAME AND ADDRESS 12...AD-Ali65 912 SENSING STRATEGIES FOR DISAMBIGURTING MONG MULTIPLE 1/1 OBJECTS IN KNOWN POSES(U) MASSACHUSETTS INST OF TECH CAMBRIDGE ARTIFICIAL ...or Dist Special 1 ’ MASSACHUSETTS INSTITUTE OF TECHNOLOGY ARTIFICIAL INTELLIGENCE LABORATORY A. I. Memo 855 August, 1985 Sensing Strategies for

Inverse Free Iterative Methods for Nonlinear Ill-Posed Operator Equations

Directory of Open Access Journals (Sweden)

Ioannis K. Argyros

2014-01-01

ill-posed operator equation F(x=y. The proposed method is a modified form of Tikhonov gradient (TIGRA method considered by Ramlau (2003. The regularization parameter is chosen according to the balancing principle considered by Pereverzev and Schock (2005. The error estimate is derived under a general source condition and is of optimal order. Some numerical examples involving integral equations are also given in this paper.

Carbon recovery rates following different wildfire risk mitigation treatments

Science.gov (United States)

M. Hurteau; M. North

2010-01-01

Sequestered forest carbon can provide a climate change mitigation benefit, but in dry temperate forests, wildfire poses a reversal risk to carbon offset projects. Reducing wildfire risk requires a reduction in and redistribution of carbon stocks, the benefit of which is only realized when wildfire occurs. To estimate the time needed to recover carbon removed and...

Intraabdominal abscessus of unknown etiology

Directory of Open Access Journals (Sweden)

Čolović Radoje

2012-01-01

Full Text Available Introduction. Intraabdominal abscesses are in 98-99% cases the result of secondary and only in 1-2% of primary peritonitis. They are easy and successfully diagnosed. Abdominal abscesses of unknown cause are extremely rare. Case Outline. The authors present a 68-year-old man, without significant data in past history, who suddenly developed epigastric pain, nausea, vomiting and leukocytosis which was treated with antibiotics resulting in the alleviation of complaints and reduction of white blood cells count. After five days ultrasonography showed incapsulated collection of dense fluid in the epigastrium confirmed by CT scan two days later. Upper endoscopy excluded ulcer and/or perforation of the stomach and duodenum. Under local anesthesia, through the upper part of the left rectal muscle, puncture followed by incision was done, and about 50 ml of dense pus was removed. Finger exploration of the cavity showed no foreign body within the cavity. Using drainage, the recovery was quick and uneventful. By preoperative and postoperative abdominal investigations no cause of the abscess was found. Two and a half years after surgery the patient remained symptom-free with normal clinical, laboratory and ultrasonographic findings. Conclusion. The authors presented an intraabdominal abscess of unknown cause that was successfully treated with antibiotics, percutaneous puncture and drainage under local anaesthesia. In spite of all diagnostic methods the cause of the abscess could not be found. Thus, such a possibility, although being rare, should be taken into account.

Risks of Terrorism, Homicide and Illness: a Methodological Consideration

Directory of Open Access Journals (Sweden)

Richard J. Chasdi

2013-12-01

Full Text Available A recurring question posed to researchers is whether or not terrorism poses similar degrees of risk as other man-made or natural disasters. There are some specialists, such as John Mueller, who argue that somewhat ironically, the threat of terrorism is vastly exaggerated.[1] This begs the question : compared to what? The underlying aim of this Research Note is to point out some basic methodological and contextual issues to consider, rather than making an attempt to provide hard answers regarding relative individual and collective risks. However, an effort is made to place some empirical findings into appropriate political and social contexts. The framework for discussion includes: basic conceptual problems regarding the notion of “risk”; a comparison of certain basic terrorism incident rates with rates for homicides and illness; and identification of possible future directions to gauge risk assessment within the context of a more holistic systems perspective. 

A New 3D Object Pose Detection Method Using LIDAR Shape Set.

Science.gov (United States)

Kim, Jung-Un; Kang, Hang-Bong

2018-03-16

In object detection systems for autonomous driving, LIDAR sensors provide very useful information. However, problems occur because the object representation is greatly distorted by changes in distance. To solve this problem, we propose a LIDAR shape set that reconstructs the shape surrounding the object more clearly by using the LIDAR point information projected on the object. The LIDAR shape set restores object shape edges from a bird's eye view by filtering LIDAR points projected on a 2D pixel-based front view. In this study, we use this shape set for two purposes. The first is to supplement the shape set with a LIDAR Feature map, and the second is to divide the entire shape set according to the gradient of the depth and density to create a 2D and 3D bounding box proposal for each object. We present a multimodal fusion framework that classifies objects and restores the 3D pose of each object using enhanced feature maps and shape-based proposals. The network structure consists of a VGG -based object classifier that receives multiple inputs and a LIDAR-based Region Proposal Networks (RPN) that identifies object poses. It works in a very intuitive and efficient manner and can be extended to other classes other than vehicles. Our research has outperformed object classification accuracy (Average Precision, AP) and 3D pose restoration accuracy (3D bounding box recall rate) based on the latest studies conducted with KITTI data sets.

Genetically Modified Foods: A Brief Overview of the Risk Assessment Process.

Science.gov (United States)

Finkelstein, Paige E

2016-02-18

Billions of people worldwide are unable to meet their daily micro nutritional needs. Genetically modified (GM) foods, while initially developed to tolerate herbicides and resist disease and insects, have the potential to help alleviate this issue that is currently posing a serious public health concern. However, there is a negative public perception surrounding GM foods, calling for more research regarding the risks that GM foods could pose to the public, specifically on the topics of allergenicity and gene transfer. The risk assessments of GM foods should be performed on a case-by-case basis, by a process outlined by the WHO. The goal of determining food safety is to obtain reasonable certainty that under normal levels of consumption, there will be no harm to people. Current research has shown that GM foods do not cause increased allergenicity or have a meaningful risk of gene transfer to people. GM foods should become publicly accepted products that can bring significant benefit to people at risk of under nutrition.

Macrobend optical sensing for pose measurement in soft robot arms

International Nuclear Information System (INIS)

Sareh, Sina; Noh, Yohan; Liu, Hongbin; Althoefer, Kaspar; Li, Min; Ranzani, Tommaso

2015-01-01

This paper introduces a pose-sensing system for soft robot arms integrating a set of macrobend stretch sensors. The macrobend sensory design in this study consists of optical fibres and is based on the notion that bending an optical fibre modulates the intensity of the light transmitted through the fibre. This sensing method is capable of measuring bending, elongation and compression in soft continuum robots and is also applicable to wearable sensing technologies, e.g. pose sensing in the wrist joint of a human hand. In our arrangement, applied to a cylindrical soft robot arm, the optical fibres for macrobend sensing originate from the base, extend to the tip of the arm, and then loop back to the base. The connectors that link the fibres to the necessary opto-electronics are all placed at the base of the arm, resulting in a simplified overall design. The ability of this custom macrobend stretch sensor to flexibly adapt its configuration allows preserving the inherent softness and compliance of the robot which it is installed on. The macrobend sensing system is immune to electrical noise and magnetic fields, is safe (because no electricity is needed at the sensing site), and is suitable for modular implementation in multi-link soft continuum robotic arms. The measurable light outputs of the proposed stretch sensor vary due to bend-induced light attenuation (macrobend loss), which is a function of the fibre bend radius as well as the number of repeated turns. The experimental study conducted as part of this research revealed that the chosen bend radius has a far greater impact on the measured light intensity values than the number of turns (if greater than five). Taking into account that the bend radius is the only significantly influencing design parameter, the macrobend stretch sensors were developed to create a practical solution to the pose sensing in soft continuum robot arms. Henceforward, the proposed sensing design was benchmarked against an electromagnetic

The Economic Impact of Terrorism in the Near East: Understanding the Threats Posed by Militant Groups

Science.gov (United States)

2015-05-21

terrorist attacks of September 11th, 2001 researchers have sought to better understand the macroeconomic consequences of terrorism. Despite a...The Economic Impact of Terrorism in the Near East: Understanding the Threats Posed by Militant Groups A Monograph by MAJ Joshua Glonek...SUBTITLE The Economic Impact of Terrorism in the Near East: Understanding the Threats Posed by Militant Groups 5a. CONTRACT NUMBER 5b. GRANT

EFEKTIVITAS PEMBELAJARAN MATEMATIKA DENGAN METODE PROBLEM POSING BERBASIS PENDIDIKAN KARAKTER

Directory of Open Access Journals (Sweden)

Eka Lia Susanti

2012-06-01

Full Text Available Abstract Tujuan penelitian ini adalah untuk mengetahui apakah pembelajaran matematika dengan metode Problem Posing berbasis pendidikan karakter di laboratorium TeenZania pada materi garis singgung lingkaran efektif. Populasi dalam penelitian ini adalah peserta didik di SMP N 2 Pati. Sampel dalam penelitian ini diambil dengan teknik cluster random sampling. Variabel dalam penelitian ini yaitu keaktifan sebagai variabel independen dan prestasi belajar sebagai variabel dependen. Cara pengambilan data dengan lembar pengamatan dan tes. Data diolah dengan uji banding t dan uji pengaruh regresi. Hasil penelitian menunjukkan bahwa prestasi belajar kelas eksperimen (82,74 secara statistik melebihi KKM (75. Dengan uji regresi linear sederhana diperoleh persamaan regresi ?=-15,847 + 1,194X dan R^2=0,829. Koefisien X merupakan bilangan positif sehingga keaktifan berpengaruh positif pada prestasi belajar sebesar 82,9%. Rata-rata prestasi belajar kelas eksperimen (82,74 dan rata-rata prestasi belajar kelas kontrol (72,91. Secara uji stastistik prestasi belajar kelas eksperimen lebih baik daripada prestasi belajar kelas kontrol. Berdasarkan hasil analisis disimpulkan (1 pembelajaran mencapai tuntas belajar; (2 adanya pengaruh positif pada keaktifan terhadap prestasi belajar; dan (3 prestasi belajar kelas eksperimen lebih baik daripada prestasi belajar kelas kontrol; sehingga pembelajaran matematika dengan metode problem posing berbasis pendidikan karakter di laboratorium TeenZania merupakan pembelajaran yang efektif. The purpose of this study was to determine whether the learning of mathematics by Problem Posing method in a TeenZania laboratory based character education in circle tangent material effectively. The population in this study were students in SMP N 2 Pati. The sample in this study were drawn by cluster random sampling technique. The variables in this study is the activity as an independent variable and learning achievement as the dependent variable

Scheme for teleportation of unknown states of trapped ion

Institute of Scientific and Technical Information of China (English)

Chen Mei-Feng; Ma Song-She

2008-01-01

A scheme is presented for teleporting an unknown state in a trapped ion system.The scheme only requires a single laser beam.It allows the trap to be in any state with a few phonons,e.g.a thermal motion.Furthermore,it works in the regime,where the Rabi frequency of the laser is on the order of the trap frequency.Thus,the teleportation speed is greatly increased,which is important for decreasing the decoherence effect.This idea can also be used to teleport an unknown ionic entangled state.

75 FR 2723 - Fair Credit Reporting Risk-Based Pricing Regulations

Science.gov (United States)

2010-01-15

...-based pricing notice to a consumer when the creditor uses a consumer report to grant or extend credit to... consumers to combat identity theft, increase the accuracy of consumer reports, and allow consumers to... consumer report is often used in evaluating the risk posed by the consumer. Creditors that engage in risk...

Risk identication of tailorable context-aware systems: a case study and lessons learned

NARCIS (Netherlands)

Zarifi Eslami, Mohammed; Sapkota, Brahmananda; Zarghami, Alireza; Vriezekolk, E.; van Sinderen, Marten J.; Wieringa, Roelf J.; Wieringa, P.A.

In this paper, we discuss possible risks posed by the application of tailorable context-aware systems in real-life practices. We use a tailorable context-aware system in the homecare domain as a case study to identify and analyse such risks. Next, we discuss which of these risks can be generalized

Risk and Emotion Among Healthy Volunteers in Clinical Trials

NARCIS (Netherlands)

Cottingham, M.D.; Fisher, J.A.

2016-01-01

Theorized as objective or constructed, risk is recognized as unequally distributed across social hierarchies. Yet the process by which social forces shape risk and risk emotions remains unknown. The pharmaceutical industry depends on healthy individuals to voluntarily test early-stage,

Hepatitis C virus infection and risk of cancer: a population-based cohort study

DEFF Research Database (Denmark)

Omland, Lars Haukali Hvass; Farkas, Dora Körmendiné; Jepsen, Peter

2010-01-01

Hepatitis C virus (HCV) infection is associated with an increased risk of primary liver cancer; however, 5- and 10-year risk estimates are needed. The association of HCV with non-Hodgkin lymphoma (NHL) is uncertain and the association with other cancers is unknown.......Hepatitis C virus (HCV) infection is associated with an increased risk of primary liver cancer; however, 5- and 10-year risk estimates are needed. The association of HCV with non-Hodgkin lymphoma (NHL) is uncertain and the association with other cancers is unknown....

Patterns of behaviour that pose potential drowning risk to hikers at Yosemite National Park.

Science.gov (United States)

Girasek, Deborah C; Marschall, Joy S; Pope, Dov

2016-01-01

To analyse patterns of departure from a popular hiking trail in Yosemite National Park, at sites where fatal drownings have occurred in the past. This study employed direct observation. For 32 days throughout the summer of 2013, study team members observed hikers who entered areas that brought them in close proximity to hazardous sections of the Merced River. Subject and environmental data were recorded for 1417 such approaches. In 81% of our observation hours, subjects entered 'risk zones.' The median number of hikers seen near/in the river was eight per hour at the Vernal Fall footbridge, and three at the top of the waterfall. A regression analysis found that air temperature and later hike starts were positively associated, and water level was negatively associated, with the rate of river approach. Means of river access were also identified. Males, teens and people who were alone were significantly more likely to be observed entering particularly dangerous areas. It is common for hikers to approach water sources during summer months, particularly as air temperatures rise. By analysing how behaviour and environmental factors co-vary, safety advocates can tailor risk reduction measures to specific settings and visitor populations. © International Society of Travel Medicine, 2016. All rights reserved. Published by Oxford University Press. For permissions, please e-mail: journals.permissions@oup.com.

Risk of transporting spent nuclear fuel by train

International Nuclear Information System (INIS)

Elder, H.K.

1981-12-01

This paper presents results of a study which analyzes the risk of transporting spent fuel by train. The risk assessment methodology consists of 4 basic steps: (1) a description of the system being analyzed; (2) identification of sequences of events that could lead to a release of material during transportation; (3) evaluation of the probability and consequences of each release sequence; and (4) assessment of the risk and evaluation of the results. The conclusion reached was that considering the substantial benefits derived from the fuel, the current spent fuel transportation system poses reasonably low risks

Prevalence and Impact of Unknown Diabetes in the ICU.

Science.gov (United States)

Carpenter, David L; Gregg, Sara R; Xu, Kejun; Buchman, Timothy G; Coopersmith, Craig M

2015-12-01

Many patients with diabetes and their care providers are unaware of the presence of the disease. Dysglycemia encompassing hyperglycemia, hypoglycemia, and glucose variability is common in the ICU in patients with and without diabetes. The purpose of this study was to determine the impact of unknown diabetes on glycemic control in the ICU. Prospective observational study. Nine ICUs in an academic, tertiary hospital and a hybrid academic/community hospital. Hemoglobin A1c levels were ordered at all ICU admissions from March 1, 2011 to September 30, 2013. Electronic medical records were examined for a history of antihyperglycemic medications or International Classification of Diseases, 9th Edition diagnosis of diabetes. Patients were categorized as having unknown diabetes (hemoglobin A1c > 6.5%, without history of diabetes), no diabetes (hemoglobin A1c 6.5%, with documented history of diabetes). None. A total of 15,737 patients had an hemoglobin A1c and medical record evaluable for the history of diabetes, and 5,635 patients had diabetes diagnosed by either medical history or an elevated hemoglobin A1c in the ICU. Of these, 1,460 patients had unknown diabetes, accounting for 26.0% of all patients with diabetes. This represented 41.0% of patients with an hemoglobin A1c > 6.5% and 9.3% of all ICU patients. Compared with patients without diabetes, patients with unknown diabetes had a higher likelihood of requiring an insulin infusion (44.3% vs 29.3%; p 180 mg/dL; p < 0.0001) and hypoglycemia (8.9% vs 2.5%; blood glucose < 70 mg/dL; p < 0.0001), higher glycemic variability (55.6 vs 28.8, average of patient SD of glucose; p < 0.0001), and increased mortality (13.8% vs 11.4%; p = 0.01). Patients with unknown diabetes represent a significant percentage of ICU admissions. Measurement of hemoglobin A1c at admission can prospectively identify a population that are not known to have diabetes but have significant challenges in glycemic control in the ICU.

Environmental occurrence and ecological risk assessment of organic UV filters in marine organisms from Hong Kong coastal waters.

Science.gov (United States)

Sang, Ziye; Leung, Kelvin Sze-Yin

2016-10-01

Organic UV filters, now considered to be emerging contaminants in aquatic ecosystems, are being intensively tracked in environmental waters worldwide. However, their environmental fate and impact of these contaminants on marine organisms remains largely unknown, especially in Asia. This work elucidates the occurrence and the ecological risks of seven UV filters detected in farmed fish, wild mussels and some other wild organisms collected from local mariculture farms in Hong Kong. For all of the organisms, ethylhexyl methoxycinnamate (EHMC) and octyl dimethyl p-aminobenzoic acid (OD-PABA) were the predominant contaminants with the highest concentrations up to 51.3 and 24.1ng/g (dw), respectively; lower levels were found for benzophenone-8 (BP-8), octocrylene (OC) and benzophenone-3 (BP-3) from risk assessment specific to the marine aquatic environment was carried out. The risk quotient (RQ) values of EHMC and BP-3 were calculated as 3.29 and 2.60, respectively, indicating these two UV filters may pose significant risks to the marine aquatic environment. Copyright © 2016 Elsevier B.V. All rights reserved.

Risk assessment and risk management of mycotoxins.

Science.gov (United States)

2012-01-01

Risk assessment is the process of quantifying the magnitude and exposure, or probability, of a harmful effect to individuals or populations from certain agents or activities. Here, we summarize the four steps of risk assessment: hazard identification, dose-response assessment, exposure assessment, and risk characterization. Risk assessments using these principles have been conducted on the major mycotoxins (aflatoxins, fumonisins, ochratoxin A, deoxynivalenol, and zearalenone) by various regulatory agencies for the purpose of setting food safety guidelines. We critically evaluate the impact of these risk assessment parameters on the estimated global burden of the associated diseases as well as the impact of regulatory measures on food supply and international trade. Apart from the well-established risk posed by aflatoxins, many uncertainties still exist about risk assessments for the other major mycotoxins, often reflecting a lack of epidemiological data. Differences exist in the risk management strategies and in the ways different governments impose regulations and technologies to reduce levels of mycotoxins in the food-chain. Regulatory measures have very little impact on remote rural and subsistence farming communities in developing countries, in contrast to developed countries, where regulations are strictly enforced to reduce and/or remove mycotoxin contamination. However, in the absence of the relevant technologies or the necessary infrastructure, we highlight simple intervention practices to reduce mycotoxin contamination in the field and/or prevent mycotoxin formation during storage.

Combined ecological risks of nitrogen and phosphorus in European freshwaters

International Nuclear Information System (INIS)

Azevedo, Ligia B.; Zelm, Rosalie van; Leuven, Rob S.E.W.; Hendriks, A. Jan; Huijbregts, Mark A.J.

2015-01-01

Eutrophication is a key water quality issue triggered by increasing nitrogen (N) and phosphorus (P) levels and potentially posing risks to freshwater biota. We predicted the probability that an invertebrate species within a community assemblage becomes absent due to nutrient stress as the ecological risk (ER) for European lakes and streams subjected to N and P pollution from 1985 to 2011. The ER was calculated as a function of species-specific tolerances to NO 3 − and total P concentrations and water quality monitoring data. Lake and stream ER averaged 50% in the last monitored year (i.e. 2011) and we observed a decrease by 22% and 38% in lake and stream ER (respectively) of river basins since 1985. Additionally, the ER from N stress surpassed that of P in both freshwater systems. The ER can be applied to identify river basins most subjected to eutrophication risks and the main drivers of impacts. - Highlights: • Ecological risk was estimated as response additions of N and P. • The risk posed by N stress is higher than that by P in European freshwaters. • Ecological risks have remained unchanged in most European river basins. - Quantifying the ecological risk of invertebrate losses due to N and P pollution

Designing a risk communication strategy for health hazards posed by traditional slaughter of goats in Tshwane, South Africa

Directory of Open Access Journals (Sweden)

Daniel N. Qekwana

2014-08-01

Full Text Available In African societies, traditional slaughter is linked to celebrations like weddings or births, as well as funerals and ancestor veneration. Participants in traditional slaughter of goats are at risk of exposure to hazards during slaughter, food preparation and consumption of goat meat. For risk mitigation strategies to be implemented, identification of the population at risk is required. This study is based on the premise that the demographic profile of people involved in traditional slaughter of goats is important for risk communication. Both structured and informal interviews were recorded and analysed using a thematic analysis. A total of 105 people were interviewed at taxi ranks in Tshwane, Gauteng. Of these, 48 were women and 57 men. The median age of women and men was 40.6 years and 44.3 years, respectively. The majority of respondents (61.9%, n = 65 interviewed were from the Gauteng Province. Sixty percent (n = 63 of respondents had a secondary education, whilst less than 4.81% (n = 5 of respondents had no formal education. This study demonstrated that interviewing commuters at taxi ranks gave access to a cross section of gender, age, language and origin. It was found that both genders were involved in traditional slaughter of goats. Risk communication strategies should thus target women as well as men. Communication strategies to mitigate the risks of traditional slaughter of goats should take into consideration the dynamic nature of demographic and cultural norms. In light of the wide demographic profile of the respondents, it was concluded that it should be possible to use taxi ranks for successful dissemination of food safety and occupational health risk mitigation messages.

Web-based visualisation of head pose and facial expressions changes: monitoring human activity using depth data

OpenAIRE

Kalliatakis, Grigorios; Vidakis, Nikolaos; Triantafyllidis, Georgios

2017-01-01

Despite significant recent advances in the field of head pose estimation and facial expression recognition, raising the cognitive level when analysing human activity presents serious challenges to current concepts. Motivated by the need of generating comprehensible visual representations from different sets of data, we introduce a system capable of monitoring human activity through head pose and facial expression changes, utilising an affordable 3D sensing technology (Microsoft Kinect sensor)...

Prevalence and Risk Factors of High Risk Human Papillomavirus ...

African Journals Online (AJOL)

Cervical cancer is the most common female cancer in northern Nigeria, yet the pattern of infection with human papillomavirus, the principal aetiologic agent is unknown. This was a preliminary study conducted in two referral hospitals in order to establish base-line data on the prevalence and risk factors for the infection in ...

A randomized controlled study of power posing before public speaking exposure for social anxiety disorder: No evidence for augmentative effects.

Science.gov (United States)

Davis, Michelle L; Papini, Santiago; Rosenfield, David; Roelofs, Karin; Kolb, Sarah; Powers, Mark B; Smits, Jasper A J

2017-12-01

This manuscript details a randomized controlled study designed to test the efficacy of power posing (i.e., briefly holding postures associated with dominance and power) as an augmentative strategy for exposure therapy for social anxiety disorder (SAD). Seventy-three individuals diagnosed with SAD were assigned to one of three conditions: power posing, submissive posing, or rest (no posing) prior to participating in an exposure therapy session. Participants were assessed for between-group differences in pre- and post-manipulation salivary hormone levels, within-session subjective experiences of fear, and pre- and 1-week post-treatment SAD severity outcome measures. Though the intervention resulted in decreased SAD symptom severity one week later, analyses revealed no significant between-group differences on any tested variables. Accordingly, this study provides no evidence to suggest that power posing impacts hormone levels or exposure therapy outcomes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Influenza and risk of later celiac disease

DEFF Research Database (Denmark)

Kårhus, Line Lund; Gunnes, Nina; Størdal, Ketil

2018-01-01

OBJECTIVES: Influenza has been linked to autoimmune conditions, but its relationship to subsequent celiac disease (CD) is unknown. Our primary aim was to determine the risk of CD after influenza. A secondary analysis examined the risk of CD following pandemic influenza vaccination. METHODS...

Decentralised output feedback control of Markovian jump interconnected systems with unknown interconnections

Science.gov (United States)

Li, Li-Wei; Yang, Guang-Hong

2017-07-01

The problem of decentralised output feedback control is addressed for Markovian jump interconnected systems with unknown interconnections and general transition rates (TRs) allowed to be unknown or known with uncertainties. A class of decentralised dynamic output feedback controllers are constructed, and a cyclic-small-gain condition is exploited to dispose the unknown interconnections so that the resultant closed-loop system is stochastically stable and satisfies an H∞ performance. With slack matrices to cope with the nonlinearities incurred by unknown and uncertain TRs in control synthesis, a novel controller design condition is developed in linear matrix inequality formalism. Compared with the existing works, the proposed approach leads to less conservatism. Finally, two examples are used to illustrate the effectiveness of the new results.

The Dynamic Features of Lip Corners in Genuine and Posed Smiles

Directory of Open Access Journals (Sweden)

Hui Guo

2018-02-01

Full Text Available The smile is a frequently expressed facial expression that typically conveys a positive emotional state and friendly intent. However, human beings have also learned how to fake smiles, typically by controlling the mouth to provide a genuine-looking expression. This is often accompanied by inaccuracies that can allow others to determine that the smile is false. Mouth movement is one of the most striking features of the smile, yet our understanding of its dynamic elements is still limited. The present study analyzes the dynamic features of lip corners, and considers how they differ between genuine and posed smiles. Employing computer vision techniques, we investigated elements such as the duration, intensity, speed, symmetry of the lip corners, and certain irregularities in genuine and posed smiles obtained from the UvA-NEMO Smile Database. After utilizing the facial analysis tool OpenFace, we further propose a new approach to segmenting the onset, apex, and offset phases of smiles, as well as a means of measuring irregularities and symmetry in facial expressions. We extracted these features according to 2D and 3D coordinates, and conducted an analysis. The results reveal that genuine smiles have higher values for onset, offset, apex, and total durations, as well as offset displacement, and a variable we termed Irregularity-b (the SD of the apex phase than do posed smiles. Conversely, values tended to be lower for onset and offset Speeds, and Irregularity-a (the rate of peaks, Symmetry-a (the correlation between left and right facial movements, and Symmetry-d (differences in onset frame numbers between the left and right faces. The findings from the present study have been compared to those of previous research, and certain speculations are made.

Renal disease masquerading as pyrexia of unknown origin

Directory of Open Access Journals (Sweden)

D Korivi

2013-01-01

Full Text Available Pyrexia of unknown origin is a challenging clinical problem. Infections, malignancies, and connective tissue diseases form the major etiologies for this condition. We report a case of a 57-year-old diabetic male who presented with fever of unknown origin for several months. The course of investigations led to a kidney biopsy which clinched the cause of his fever as well as the underlying diagnosis. The light microscopy findings of expansile storiform fibrosis with a dense inflammatory infiltrate suggested the diagnosis which was confirmed by positive staining of Immunoglobulin G4, the dense lympho-plasmacytic infiltrate and elevated serum IgG4 concentrations. A course of steroids followed by mycophenolate mofetil as maintenance immunosuppression rendered the patient afebrile with improvement of renal function.

MODEL PEMBELAJARAN PROBLEM POSING DENGAN PENDEKATAN SAINTIFIK UNTUK MENINGKATKAN KEMAMPUAN PEMECAHAN MASALAH

Directory of Open Access Journals (Sweden)

Adi Purnomo

2015-08-01

Full Text Available Tujuan penelitian ini untuk menghasilkan perangkat pembelajaran model problem posing pendekatan saintifik yang valid, praktis dan efektif. Penelitian ini merupakan penelitian pengembangan dengan model Thiagarajan. Pengolahan data penelitian untuk uji kevalidan dan kepraktisan dilakukan dengan menghitung rata-rata skor, sedangkan uji keefektifan dilakukan dengan uji t, uji proporsi, uji regresi, uji t berpasangan, dan uji normalitas gain. Hasil pengembangan diperoleh perangkat pembelajaran dinyatakan valid dengan rata-rata skor validasi silabus 4,3, RPP 4,31, buku peserta didik 4,24, LKPD 4,16, TKPM 4,19, dari skor maksimal 5,00. Perangkat pembelajaran praktis berdasarkan hasil pengamatan kemampuan guru 4,5 (sangat baik dan respon peserta didik 3,8 (baik. Implementasi perangkat pembelajaran efektif yang ditunjukkan dengan: (1 ketuntasan klasikal TKKM melampaui 75%, rata-rata kelas melampaui KKM; (2 kemampuan pemecahan masalah peserta didik yang pembelajarannya menggunakan model problrm posing pendekatan saintifik lebih baik dari pada peserta didik dengan pembelajaran konvensional; (3 keterampilan proses saintifik dan karakter kemandirian berpengaruh positif terhadap kemampuan pemecahan masalah; dan (4 adanya peningkatan pemecahan masalah dan mendiskripsikan peningkatan kemampuan pemecahan masalah berdasarkan Taksonomi SOLO.The purpose of this research to development lesson plan through problem posing model with scientific approach which are valid, practical, and effective. The development research using Thiagarajan model. Processing data for validation and practice can be done calculating the score average, while effectivity by use of t-test, proportion test, regression test, paired t-test, n-gain. The lesson plan is valid based on the average of validation scores syllabus 4,3, RPP 4,31, student book 4,24, LKPD 4,16, TKPM 4,19.  The lesson plan is practical based on the result of observation teacher ability 4,53 and student response 4,23. The

Posed versus spontaneous facial expressions are modulated by opposite cerebral hemispheres.

Science.gov (United States)

Ross, Elliott D; Pulusu, Vinay K

2013-05-01

Clinical research has indicated that the left face is more expressive than the right face, suggesting that modulation of facial expressions is lateralized to the right hemisphere. The findings, however, are controversial because the results explain, on average, approximately 4% of the data variance. Using high-speed videography, we sought to determine if movement-onset asymmetry was a more powerful research paradigm than terminal movement asymmetry. The results were very robust, explaining up to 70% of the data variance. Posed expressions began overwhelmingly on the right face whereas spontaneous expressions began overwhelmingly on the left face. This dichotomy was most robust for upper facial expressions. In addition, movement-onset asymmetries did not predict terminal movement asymmetries, which were not significantly lateralized. The results support recent neuroanatomic observations that upper versus lower facial movements have different forebrain motor representations and recent behavioral constructs that posed versus spontaneous facial expressions are modulated preferentially by opposite cerebral hemispheres and that spontaneous facial expressions are graded rather than non-graded movements. Published by Elsevier Ltd.

Mechanistic modeling of insecticide risks to breeding birds in ...

Science.gov (United States)

Insecticide usage in the United States is ubiquitous in urban, suburban, and rural environments. In evaluating data for an insecticide registration application and for registration review, scientists at the United States Environmental Protection Agency (USEPA) assess the fate of the insecticide and the risk the insecticide poses to the environment and non-target wildlife. At the present time, current USEPA risk assessments do not include population-level endpoints. In this paper, we present a new mechanistic model, which allows risk assessors to estimate the effects of insecticide exposure on the survival and seasonal productivity of birds known to use agricultural fields during their breeding season. The new model was created from two existing USEPA avian risk assessment models, the Terrestrial Investigation Model (TIM v.3.0) and the Markov Chain Nest Productivity model (MCnest). The integrated TIM/MCnest model has been applied to assess the relative risk of 12 insecticides used to control corn pests on a suite of 31 avian species known to use cornfields in midwestern agroecosystems. The 12 insecticides that were assessed in this study are all used to treat major pests of corn (corn root worm borer, cutworm, and armyworm). After running the integrated TIM/MCnest model, we found extensive differences in risk to birds among insecticides, with chlorpyrifos and malathion (organophosphates) generally posing the greatest risk, and bifenthrin and ë-cyhalothrin (

A cost–benefit analysis of mitigation options for optimal management of risks posed by flow-like phenomena

DEFF Research Database (Denmark)

Narasimhan, Harikrishna; Ferlisi, Settimio; Cascini, Leonardo

2016-01-01

) (Nathwani et al. in Affordable safety by choice: the life quality method. University of Waterloo, Waterloo, 1997; Nathwani et al. in Engineering decisions for life quality: how safe is safe enough? Springer, London, 2009). A case study involving the cost–benefit analysis of selected packages of measures......Decisions associated with life safety risk management of natural hazards can involve significant potential consequences for public safety. Given possible limitations to available societal resources, it is therefore necessary to establish a clear and rational basis for the allocation of resources...... towards risk management. A viable approach for utilising life safety risk assessment in public safety decisions that are aimed at improving the welfare of the public and other stakeholders is described in this paper. This approach is conceptually based on the principles of the Life Quality Index (LQI...

Tooth display and lip position during spontaneous and posed smiling in adults.

NARCIS (Netherlands)

Geld, P.A.A.M. van der; Oosterveld, P.; Berge, S.J.; Kuijpers-Jagtman, A.M.

2008-01-01

OBJECTIVE: To analyze differences in tooth display, lip-line height, and smile width between the posed smiling record, traditionally produced for orthodontic diagnosis, and the spontaneous (Duchenne) smile of joy. MATERIAL AND METHODS: The faces of 122 male participants were each filmed during

Autonomous Flight in Unknown Indoor Environments

OpenAIRE

Bachrach, Abraham Galton; He, Ruijie; Roy, Nicholas

2009-01-01

This paper presents our solution for enabling a quadrotor helicopter, equipped with a laser rangefinder sensor, to autonomously explore and map unstructured and unknown indoor environments. While these capabilities are already commodities on ground vehicles, air vehicles seeking the same performance face unique challenges. In this paper, we describe the difficulties in achieving fully autonomous helicopter flight, highlighting the differences between ground and helicopter robots that make it ...

Automated pose estimation of objects using multiple ID devices for handling and maintenance task in nuclear fusion reactor

International Nuclear Information System (INIS)

Umetani, Tomohiro; Morioka, Jun-ichi; Tamura, Yuichi; Inoue, Kenji; Arai, Tatsuo; Mae, Yasusi

2011-01-01

This paper describes a method for the automated estimation of three-dimensional pose (position and orientation) of objects by autonomous robots, using multiple identification (ID) devices. Our goal is to estimate the object pose for assembly or maintenance tasks in a real nuclear fusion reactor system, with autonomous robots cooperating in a virtual assembly system. The method estimates the three-dimensional pose for autonomous robots. This paper discusses a method of motion generation for ID acquisition using the sensory data acquired by the measurement system attached to the robots and from the environment. Experimental results show the feasibility of the proposed method. (author)

Voxel-based registration of simulated and real patient CBCT data for accurate dental implant pose estimation

Science.gov (United States)

Moreira, António H. J.; Queirós, Sandro; Morais, Pedro; Rodrigues, Nuno F.; Correia, André Ricardo; Fernandes, Valter; Pinho, A. C. M.; Fonseca, Jaime C.; Vilaça, João. L.

2015-03-01

The success of dental implant-supported prosthesis is directly linked to the accuracy obtained during implant's pose estimation (position and orientation). Although traditional impression techniques and recent digital acquisition methods are acceptably accurate, a simultaneously fast, accurate and operator-independent methodology is still lacking. Hereto, an image-based framework is proposed to estimate the patient-specific implant's pose using cone-beam computed tomography (CBCT) and prior knowledge of implanted model. The pose estimation is accomplished in a threestep approach: (1) a region-of-interest is extracted from the CBCT data using 2 operator-defined points at the implant's main axis; (2) a simulated CBCT volume of the known implanted model is generated through Feldkamp-Davis-Kress reconstruction and coarsely aligned to the defined axis; and (3) a voxel-based rigid registration is performed to optimally align both patient and simulated CBCT data, extracting the implant's pose from the optimal transformation. Three experiments were performed to evaluate the framework: (1) an in silico study using 48 implants distributed through 12 tridimensional synthetic mandibular models; (2) an in vitro study using an artificial mandible with 2 dental implants acquired with an i-CAT system; and (3) two clinical case studies. The results shown positional errors of 67+/-34μm and 108μm, and angular misfits of 0.15+/-0.08° and 1.4°, for experiment 1 and 2, respectively. Moreover, in experiment 3, visual assessment of clinical data results shown a coherent alignment of the reference implant. Overall, a novel image-based framework for implants' pose estimation from CBCT data was proposed, showing accurate results in agreement with dental prosthesis modelling requirements.

Probabilistic ecological risk assessment of polycyclic aromatic hydrocarbons in southwestern catchments of the Bohai Sea, China.

Science.gov (United States)

Zeng, Lin; Zeng, Siyu; Dong, Xin; Zhang, Tianzhu; Chen, Jining

2013-10-01

A probability risk assessment was undertaken to study the individual and combined ecological risks induced by six polycyclic aromatic hydrocarbons (PAHs) both in surface water and sediment from southwestern catchments of the Bohai Sea, China. The actual measured PAH concentrations in water and sediment were compared with toxicity effect data (the 10th percentile of predicted no effect concentration) to calculate the risk quotients (RQs) for an individual PAH. The equilibrium partitioning method was applied to estimate toxicity data in sediment. A method based on the equivalent concentration concept was proposed and applied to assess the combined ecological risk of multiple PAHs. Monte Carlo simulation and bootstrap technique were utilized to calculate the distribution of RQs and associated uncertainties. The ecological safety level was defined by RQ ≤ 1. Results indicated that both in water and sediment, fluoranthene and pyrene posed the highest risks, whereas acenaphthene and fluorene posed negligible risks. Naphthalene and phenanthrene did not pose risks to the ecological community in surface water but had relatively higher risks in sediment. The median RQs of combined risk in surface water and sediment were 0.934 and 2.42, and the probabilities of RQ > 1 were up to 0.473 and 0.599, respectively, which were much higher than the individual compound acting alone. The risk level in sediment was quite higher than in surface water probably owing to the non-equilibrium distribution between two phases, which suggested that local authorities should focus more on sediment quality management.