WorldWideScience

Sample records for based observational study

  1. A comparative study between a high-gain interconnected observer and an adaptive observer applied to IM-based WECS

    Science.gov (United States)

    Naifar, Omar; Boukettaya, Ghada; Oualha, Abdelmajid; Ouali, Abderrazak

    2015-05-01

    This paper is devoted to the investigation of the potentialities of induction motor sensorless strategies in speed control applications. A comparison study is carried out between two observation approaches dedicated to speed control strategies of induction machine (IM)-based wind energy conversion systems (WECS) under parametric variations, such as: i) the adaptive observer approach, which is based on the speed adaptation law and ii) the interconnected observer, that offers robustness and stability of the system with reduced CPU time. The comparison study is achieved considering four performance criteria: stability, robustness with respect to the variations of the machine inductances, robustness with respect to the variations of the machine resistances, feasibility of the torque estimation. It has been found that the introduced interconnected observer exhibits a higher performance than the traditional adaptive one, with respect to the above-cited comparison criteria.

  2. Implementation of Evidence-Based Literacy Practices in Middle School Response to Intervention: An Observation Study

    Science.gov (United States)

    Ciullo, Stephen; Lembke, Erica S.; Carlisle, Abigail; Thomas, Cathy Newman; Goodwin, Marilyn; Judd, Laura

    2016-01-01

    The authors report findings from a systematic observational study of middle school educators (Grades 6-8) in two states who provided reading interventions within Tier 2 and Tier 3 of a Response to Intervention (RTI) framework. Intervention sessions were coded and analyzed to understand (a) the frequency and type of evidence-based strategies…

  3. Bias adjustment of satellite-based precipitation estimation using gauge observations: A case study in Chile

    Science.gov (United States)

    Yang, Zhongwen; Hsu, Kuolin; Sorooshian, Soroosh; Xu, Xinyi; Braithwaite, Dan; Verbist, Koen M. J.

    2016-04-01

    Satellite-based precipitation estimates (SPEs) are promising alternative precipitation data for climatic and hydrological applications, especially for regions where ground-based observations are limited. However, existing satellite-based rainfall estimations are subject to systematic biases. This study aims to adjust the biases in the Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Cloud Classification System (PERSIANN-CCS) rainfall data over Chile, using gauge observations as reference. A novel bias adjustment framework, termed QM-GW, is proposed based on the nonparametric quantile mapping approach and a Gaussian weighting interpolation scheme. The PERSIANN-CCS precipitation estimates (daily, 0.04°×0.04°) over Chile are adjusted for the period of 2009-2014. The historical data (satellite and gauge) for 2009-2013 are used to calibrate the methodology; nonparametric cumulative distribution functions of satellite and gauge observations are estimated at every 1°×1° box region. One year (2014) of gauge data was used for validation. The results show that the biases of the PERSIANN-CCS precipitation data are effectively reduced. The spatial patterns of adjusted satellite rainfall show high consistency to the gauge observations, with reduced root-mean-square errors and mean biases. The systematic biases of the PERSIANN-CCS precipitation time series, at both monthly and daily scales, are removed. The extended validation also verifies that the proposed approach can be applied to adjust SPEs into the future, without further need for ground-based measurements. This study serves as a valuable reference for the bias adjustment of existing SPEs using gauge observations worldwide.

  4. Virtual colleagues, virtually colleagues—physicians’ use of Twitter: a population-based observational study

    OpenAIRE

    Brynolf, Anne; Johansson, Stefan; Appelgren, Ester; Lynoe, Niels; Edstedt Bonamy, Anna-Karin

    2013-01-01

    Objective To investigate potential violations of patient confidentiality or other breaches of medical ethics committed by physicians and medical students active on the social networking site Twitter. Design Population-based cross-sectional observational study. Setting The social networking site Twitter (Swedish-speaking users, n=298819). Population Physicians and medical students (Swedish-speaking users, n=237) active on the social networking site Twitter between July 2007 and March 2012. Mai...

  5. A population-based observational study of diabetes during pregnancy in Victoria, Australia, 1999–2008

    OpenAIRE

    Abouzeid, Marian; Versace, Vincent L; Janus, Edward D; Davey, Mary-Ann; Philpot, Benjamin; Oats, Jeremy; Dunbar, James A

    2014-01-01

    Objectives This paper reports secular trends in diabetes in pregnancy in Victoria, Australia and examines the effect of including or excluding women with pre-existing diabetes on gestational diabetes (GDM) prevalence estimates. Design Population-based observational study. Setting All births in Victoria, Australia between 1999 and 2008 Participants 634 932 pregnancies resulting in a birth registered with the Victorian Perinatal Data Collection Outcome measures Crude and age-standardised secula...

  6. A mixed methods observational simulation-based study of interprofessional team communication

    DEFF Research Database (Denmark)

    Paltved, Charlotte; Nielsen, Kurt; Musaeus, Peter

    2013-01-01

    Interprofessional team communication has been identified as an important focus for safety in medical emergency care. However, in-depth insight into the complexity of team communication is limited. Video observational studies might fill a gap in terms of understanding the meaning of specific...... communication interactions and link team performance to patient outcome. This study had two aims. First, to develop a theory-based evaluation instrument that measures and qualifies team communication. And second, to investigate the quality and content of summaries and re-evaluations evolving step wise and...

  7. Accretion dynamics and disk evolution in NGC 2264: a study based on the Corot photometric observations

    CERN Document Server

    Alencar, S H P; Guimaraes, M M; McGinnis, P T; Gameiro, J F; Bouvier, J; Aigrain, S; Flaccomio, E; Favata, F

    2010-01-01

    The young cluster NGC 2264 was observed with the Corot satellite for 23 days uninterruptedly in March 2008 with unprecedent photometric accuracy. We present here the first results of the analysis of the accreting population. We intended to look for possible light curve variability of the same nature as that observed in the classical T Tauri star AA Tau, which was attributed to a magnetically controlled inner disk warp, which is directly associated with the interaction between the stellar magnetic field and the inner disk region. We analysed the Corot light curves of 83 previously known classical T Tauri stars that belong to NGC 2264 and classified them according to their morphology. We also studied the Corot light curve morphology as a function of a Spitzer-based classification of the star-disk systems. The classification derived on the basis of the Corot light curve morphology agrees very well with the Spitzer IRAC-based classification of the systems. The percentage of AA Tau-like light curves decreases as t...

  8. Tragaldabas: a muon ground-based detector for the study of the solar activity; first observations

    Science.gov (United States)

    José Blanco, Juan

    2016-04-01

    A new RPC-based cosmic ray detector, TRAGALDABAS (acronym of "TRAsGo for the AnaLysis of the nuclear matter Decay, the Atmosphere, the earth's B-field And the Solar activity") has been installed at the Univ. of Santiago de Compostela, Spain (N:42°52'34",W:8°33'37"). The detector, in its present layout, consists of three 1.8 m2 planes of three 1mm-gap glass RPCs. Each plane is readout with 120 pads with grounded guard electrodes between them to minimize the crosstalk noise. The main performances of the detectors are: an arrival time resolution of about ~300 ps, a tracking angular resolution below 3°, a detection efficiency close to 1, and a solid angle acceptance of ~5 srad. TRAGALDABAS will be able to monitor the cosmic ray low energy component strongly modulated by solar activity by mean the observation of secondary muons from the interaction between cosmic rays and atmospheric molecules. Its cadence and its angular resolution will allow to study in detail, small variations in cosmic ray anisotropy. These variations can be a key parameter to understand the effect of solar disturbances on the propagation of cosmic ray in the inner heliosphere and, maybe, provide a new tool for space weather analysis. In this work first TRAGALDABAS observations of solar events are shown

  9. Validation of an image-based technique to assess the perceptual quality of clinical chest radiographs with an observer study

    Science.gov (United States)

    Lin, Yuan; Choudhury, Kingshuk R.; McAdams, H. Page; Foos, David H.; Samei, Ehsan

    2014-03-01

    We previously proposed a novel image-based quality assessment technique1 to assess the perceptual quality of clinical chest radiographs. In this paper, an observer study was designed and conducted to systematically validate this technique. Ten metrics were involved in the observer study, i.e., lung grey level, lung detail, lung noise, riblung contrast, rib sharpness, mediastinum detail, mediastinum noise, mediastinum alignment, subdiaphragm-lung contrast, and subdiaphragm area. For each metric, three tasks were successively presented to the observers. In each task, six ROI images were randomly presented in a row and observers were asked to rank the images only based on a designated quality and disregard the other qualities. A range slider on the top of the images was used for observers to indicate the acceptable range based on the corresponding perceptual attribute. Five boardcertificated radiologists from Duke participated in this observer study on a DICOM calibrated diagnostic display workstation and under low ambient lighting conditions. The observer data were analyzed in terms of the correlations between the observer ranking orders and the algorithmic ranking orders. Based on the collected acceptable ranges, quality consistency ranges were statistically derived. The observer study showed that, for each metric, the averaged ranking orders of the participated observers were strongly correlated with the algorithmic orders. For the lung grey level, the observer ranking orders completely accorded with the algorithmic ranking orders. The quality consistency ranges derived from this observer study were close to these derived from our previous study. The observer study indicates that the proposed image-based quality assessment technique provides a robust reflection of the perceptual image quality of the clinical chest radiographs. The derived quality consistency ranges can be used to automatically predict the acceptability of a clinical chest radiograph.

  10. Land cover change impacts on surface ozone: an observation-based study

    Science.gov (United States)

    Zhang, Yi; Lin, Jintai

    2016-04-01

    Ozone air quality is a critical global environmental issue. Although it is clear that industrialization and urbanization has increased surface ozone through enhanced emissions of its precursors, much less is known about the role of changes in land cover and land use. Human activities have substantially altered the global land cover and land use through agriculture, urbanization, deforestation, and afforestation. Changes in Land cover and land use affect the ozone levels by altering soil emissions of nitrogen oxides (NOx), biogenic emissions of volatile organic compounds (VOCs), and dry deposition of ozone itself. This study performs a series of experiments with a chemical transport model based on satellite observation of land types to analyze the influences of changes in land cover/land use and their impact on surface ozone concentration. Our results indicate that land cover change explains 1-2 ppbv of summertime surface ozone increase in the Western United States and 1-6 ppbv of increase in Southern China between 2001 and 2012. This is largely driven by enhanced isoprene emissions and soil NOx emissions. It is also found that land cover change itself elevates summertime surface zone in Canadian coniferous forests by up to 4 ppbv mainly through substantial decreases in ozone dry deposition associated with increased vegetation density in a warmer climate.

  11. The impact of European forests on cloud cover: an observation-based study

    Science.gov (United States)

    Teuling, Ryan; Melsen, Lieke; Vila-Guerau de Arellano, Jordi; van Heerwaarden, Chiel; Miralles, Diego; Taylor, Chris; Stegehuis, Annemiek; Fokke Meirink, Jan; Nabuurs, Gert-Jan

    2016-04-01

    The impact of temperate forests on their environment is still uncertain [1]. While forests generally have a lower albedo, the flux partitioning over forests and its relation to weather conditions is still poorly understood [2,3], complicating attempts to study impacts of forest cover on atmospheric conditions through modeling. Effects of land surface conditions on boundary-layer humidity and cloud formation can also be very non-linear [4]. Furthermore, the study of hydrological and climate impacts of temperate European forests is complicated because forests are strongly fragmented and often can be found on hilly terrain, making it impossible to attribute differences in for instance cloud cover or runoff directly to forest cover. Only few regions exist where forests can be found in absence of strong topography of a size large enough to result in near-equilibrium between the atmospheric boundary layer and local surface conditions. In this study, we analyse 10 years (2004-2013) of cloud cover observations from the Meteosat Second Generation satellite platform at a 15-minute temporal resolution. These observations come from a physically-based cloud product at the 6 km resolution [5], and a statistical cloud product based on the high-resolution visible imagery (1 km resolution). We focus on two regions in France where large forests are found which satisfy the following criteria: a) absence of strong topography, and b) presence of sharp contrast between forest and non-forest regions. Cloud occurrence is expressed by the fraction of the daytime that clouds are detected within a pixel. We find that in particular in summer and late summer, clouds are much more likely to occur over forest than over the surrounding non-forest land (difference in the order of 0.2). An opposite signal, but of much weaker magnitude, is found during springtime, when clouds are less likely to develop over forest. Difference in cloud occurrence is consistent with MODIS-derived differences in EVI

  12. The value of site-based observations complementary to naturalistic driving observations : a pilot study on the right turn manoeuvre.

    NARCIS (Netherlands)

    Nes, N. van Christoph, M.W.T. Hoedemaeker, M. & Horst, A.R.A. van der

    2013-01-01

    Naturalistic driving studies are increasingly applied in different shapes and sizes. The European project PROLOGUE has investigated the value and feasibility of a large-scale naturalistic driving study in Europe. Within PROLOGUE several pilot studies have been conducted in different countries. The D

  13. The value of site-based observations complematary to naturalistic driving observations : a pilot study on the right turn manoeuvre.

    NARCIS (Netherlands)

    Nes, N. van Christoph, M.W.T. Hoedemaeker, M. & Horst, A.R.A. van der

    2013-01-01

    Naturalistic driving studies are increasingly applied in different shapes and sizes. The European project PROLOGUE has investigated the value and feasibility of a large-scale naturalistic driving study in Europe. Within PROLOGUE several pilot studies have been conducted in different countries. The D

  14. Multiple Integrated Examinations: An Observational Study of Different Academic Curricula Based on a Business Administration Assessment

    Science.gov (United States)

    Ardolino, Piermatteo; Noventa, Stefano; Formicuzzi, Maddalena; Cubico, Serena; Favretto, Giuseppe

    2016-01-01

    An observational study has been carried out to analyse differences in performance between students of different undergraduate curricula in the same written business administration examination, focusing particularly on possible effects of "integrated" or "multi-modular" examinations, a recently widespread format in Italian…

  15. On family-based genome-wide association studies with large pedigrees: observations and recommendations

    OpenAIRE

    Fardo, David W.; Zhang, Xue; Ding, Lili; He, Hua; Kurowski, Brad; Alexander, Eileen S.; Mersha, Tesfaye B.; Pilipenko, Valentina; Kottyan, Leah; Nandakumar, Kannabiran; Martin, Lisa

    2014-01-01

    Family based association studies are employed less often than case-control designs in the search for disease-predisposing genes. The optimal statistical genetic approach for complex pedigrees is unclear when evaluating both common and rare variants. We examined the empirical power and type I error rates of 2 common approaches, the measured genotype approach and family-based association testing, through simulations from a set of multigenerational pedigrees. Overall, these results suggest that ...

  16. An observational study based on the interaction between the paediatric patient and radiographer

    International Nuclear Information System (INIS)

    Background: The practice of paediatric radiography requires a completely different skill set to that of adult radiography. Often, obtaining a paediatric patient's cooperation is the most difficult aspect of the role. Ensuring that a child cooperates for the examination can make positioning easier, thereby potentially providing a more diagnostic image. Aim: The aim of this study was to observe the interaction between the paediatric patient and the radiographer and to uncover techniques used by the radiographer to help alleviate any fear or stress that the child might have had. Method: A direct observational method was conducted, after both the radiographer and the child's guardians provided full written consent. The actions of the radiographer and resultant reactions from the child were recorded on an observational checklist designed for paediatric examinations. Results: Seventy-nine patients aged between three months to fifteen years and thirteen radiographers with no specific paediatric training other than experience were observed. Examinations observed included lower limb, upper limb, pelvis, abdomen and chest projections. The data gathered were the result of radiographer actions when interacting with both happy and sad children. Conclusions: Successful methods of alleviating a child's fear and anxiety whilst in the X-ray room included the use of child friendly equipment such as colourful lead protection and posters on the wall, a simple explanation of what the equipment is before moving it, offering rewards such as stickers and praise and showing the child their image after the examination. When time was short and the workload was high, it was observed that radiographers were less likely to spend time calming the child down and instead were more focused on completing the examination as quickly as possible. - Highlights: • Seventy-nine patients and thirteen radiographers were observed in this study. • The use of child-friendly equipment and

  17. Designing Health Websites Based on Users’ Web-Based Information-Seeking Behaviors: A Mixed-Method Observational Study

    Science.gov (United States)

    Pang, Patrick Cheong-Iao; Verspoor, Karin; Pearce, Jon

    2016-01-01

    Background Laypeople increasingly use the Internet as a source of health information, but finding and discovering the right information remains problematic. These issues are partially due to the mismatch between the design of consumer health websites and the needs of health information seekers, particularly the lack of support for “exploring” health information. Objective The aim of this research was to create a design for consumer health websites by supporting different health information–seeking behaviors. We created a website called Better Health Explorer with the new design. Through the evaluation of this new design, we derive design implications for future implementations. Methods Better Health Explorer was designed using a user-centered approach. The design was implemented and assessed through a laboratory-based observational study. Participants tried to use Better Health Explorer and another live health website. Both websites contained the same content. A mixed-method approach was adopted to analyze multiple types of data collected in the experiment, including screen recordings, activity logs, Web browsing histories, and audiotaped interviews. Results Overall, 31 participants took part in the observational study. Our new design showed a positive result for improving the experience of health information seeking, by providing a wide range of information and an engaging environment. The results showed better knowledge acquisition, a higher number of page reads, and more query reformulations in both focused and exploratory search tasks. In addition, participants spent more time to discover health information with our design in exploratory search tasks, indicating higher engagement with the website. Finally, we identify 4 design considerations for designing consumer health websites and health information–seeking apps: (1) providing a dynamic information scope; (2) supporting serendipity; (3) considering trust implications; and (4) enhancing interactivity

  18. Migraine and breast cancer risk: a meta-analysis of observational studies based on MOOSE compliant.

    Science.gov (United States)

    Wu, Xiujuan; Wang, Minghao; Li, Shifei; Zhang, Yi

    2016-07-01

    It has long been speculated that migraine may contribute to an increased risk of breast cancer; however, results from previous studies have been inconclusive. To definitively interrogate this issue, we performed a meta-analysis to assess the correlation between these 2 diseases.Medline and PubMed were searched to identify relevant studies that had been published until October 2015. Based on a random effects model, relative risk (RR) and the corresponding 95% confidence interval (CI) were used to evaluate the pooled risk.A total of 7 studies involving 17,776 cases and 162,954 participants were included. Our study revealed that there was an inverse relationship between migraine and total breast cancer risk, with RR (95%CI) was 0.78 (0.66, 0.92). In subgroup-analysis, such an inverse relationship was also identified in the ductal and lobular carcinoma, case-control studies, and the ER/PR breast cancer. Little evidence indicative of a publication bias was uncovered.In conclusion, our study implicates a statistically significant inverse association between migraine and the risk of breast cancer. However, larger prospective cohort studies concerning other geographic populations to assess the association between migraine and the breast cancer risk are warranted. PMID:27472675

  19. Self-healing of lime based mortars: Microscopy observations on case studies

    OpenAIRE

    Lubelli, B.; Nijland, T.G.; Hees, R.P.J. van

    2011-01-01

    Lime mortars have, up to a certain extent, a self-healing capacity which may contribute to their durability. Self-healing in lime mortars consists of a process of dissolution, transport and re-precipitation of calcium compounds to heal cracks and fissures. The spontaneous occurrence of self-healing in lime-based mortars is a well known phenomenon; to date, however, little research has been done on its occurrence in the practice. This study aims at gaining a better understanding of the self-he...

  20. Spline-based Study of the Extragalactic Background Light Spectrum using Gamma-Ray Observations

    Science.gov (United States)

    Bose, Anoushka; Rathmann-Bloch, Julia; Biteau, Jonathan; Williams, David A.

    2016-01-01

    The extragalactic background light (EBL) is made of all the light emitted by stars and galaxies throughout cosmic history. Expanding on the work of Biteau & Williams 2015, we develop a novel natural cubic spline model of the local EBL spectrum and constrain its parameters using the gamma-ray spectra of 38 blazars measured in the high-energy (HE, 0.1 to 100 GeV) and very-high-energy (VHE, 0.1 to 20 TeV) bands. Starting from this best-fit model, we then study the so-called "delta gamma" (ΔΓ) observable, defined as the difference between the VHE and HE photon indices. This second study is focused on a subset of nine BL Lac objects. The application of a scaling factor to the cosmic optical background (0.1 - 10 nm) significantly impacts the predicted ΔΓ as a function of redshift, whereas a similar modification of the cosmic infrared background (10 - 1000 nm) has no impact. We conclude that the simple delta gamma approach can only constrain part of the EBL spectrum, while a detailed study of the spectra, such as presented in the first part of this research, is needed to constrain the cosmic infrared background.

  1. "Bacterial Meningitis in children and adolescents: an observational study based on the national surveillance system"

    Directory of Open Access Journals (Sweden)

    Dickinson Félix O

    2005-11-01

    Full Text Available Abstract Background Bacterial meningitis is a group of life threatening infections that mostly affect children and adolescents, and may be the cause of severe neurological sequelae. Cuba has implemented massive vaccination programmes against both Neisseria meningitidis (serogroup C in 1979 and B in 1987, and Haemophilus influenzae type b (1999, two of the main causal pathogens. We described and discussed some epidemiological aspects of the current status of bacterial meningitis to learn from the Cuban experience. Methods A nationwide observational study on children and adolescents from 1 to 18 years old was carried out from 1998 to 2003, estimating the incidence and case-fatality rate by age group and causal pathogens, as well as the seasonality and frequency of overcrowded dormitories. The association between disease and attendance to day care centres or boarding schools was estimated by using relative risk (Chi-squared test and Fisher Exact Test. Results The overall number of cases was 1023; the incidence ranged from 3.4 to 8.5 per 100 000 population, with the higher figures in children 1–5 years old (16.8 per 100 000 population. Streptococcus pneumoniae, Haemophilus influenzae type b and Neisseria meningitidis serogroup B were the main identified agents. The average case-fatality rate was 10.5% and the most lethal agents were Streptococcus pneumoniae (27% and Haemophilus influenzae type b (10.7%. Overall percentage of cases who slept in overcrowded dormitories was 15%, reaching 30.6% in adolescents. Seasonality was only evident among meningococcal meningitis cases between September–October. The attendance to boarding high school showed an association with disease only in 1998 and 1999 (RR = 2.1; p > 0.05. Conclusion The highest incidence of bacterial meningitis was observed among children from 1–5 years old. Pneumococcus was both the leading causal and the most lethal agent. Sleeping in overcrowded dormitories was more frequent among

  2. ACUTE UNDIFFERENTIATED FEBRILE ILLNESS AMONG ADULTS – A HOSPITAL BASED OBSERVATIONAL STUDY

    Directory of Open Access Journals (Sweden)

    Shivkumar

    2013-04-01

    Full Text Available ABSTRACT. BACKGROUND: Fever is a burning issue in the tropics and the mos t common cause of morbidity. Quite frequently this fever goes undi agnosed because of many reasons like the lack of diagnostic facilities, insufficient epidemi ological data available on causes of fever, and so on. This research study was aimed to find out the e tiology and clinical markers of Acute Undifferentiated Febrile Illness [AUFI] among the r ural population of Southern India. METHODOLOGY: This prospective, observational study was conducted at Government Villupuram Medical College and Hospital, a rural ter tiary care centre in Tamil Nadu, India. Consecutive hospitalised adult patients [>16 years] with AUFI[5-14 days fever] were enrolled into the study from August 2010 to February 2012 [1 8 months].Upon enrollment, detailed history was recorded, physical examination done and basic blood tests including biochemical examination, smear study for malaria, blood culture s and serology for the commonly encountered infections were done according to study protocol. The patients were followed up until clinical recovery and convalescence. The data were entered in MS excel and analyzed using Epi-info software 2008 version. RESULTS: A total of 403 patients were included in the study . The distribution of AUFI included Malaria 133[33%], Typhoid 83[20.59%], Dengue 42[10.4%], Leptospirosis 25[6.2%], and other causes 36[8.9%] and unknown cause 84[20.84%]. Malaria patients were significantly associated with jaundice , altered mentation, travel outside the district, elevated AST/ALT levels, thrombocytopenia and splenomegaly. Typhoid fever was associated with longer fever duration, abdominal pai n, coated tongue, relative bradycardia, normal platelet counts and low leucocyte count. Deng ue fever could be predicted by rash, pruritis, petechiae ,retro-orbital pain and low platele t counts. Leptospirosis patients showed significant association with conjunctival suffusion , muscle

  3. SELF-LEARNING METHODS PREFERRED BY SECOND YEAR MBBS STUDENTS IN UNDERSTANDING PHARMACOLOGY: AN OBSERVATIONAL QUESTIONNAIRE BASED STUDY

    OpenAIRE

    Padmanabha Thiruganahalli; Manu; Chandrakantha; Neha; Narasimhamurthy Kalenahally

    2016-01-01

    BACKGROUND AIMS To evaluate the self-learning habits via different learning styles which can influence and be a useful indicator for potential learning performance of an individual. MATERIAL & METHODS Observational questionnaire based study to evaluate self-learning habits among Second year undergraduates, Adichunchanagiri Institute of Medical Sciences, B. G. Nagara, Mandya, Karnataka. RESULTS 50.55% had an opinion that Problem Based Learning (PBL) stimulates self-d...

  4. US Air Force Base Observations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hourly observations taken by U.S. Air Force personnel at bases in the United States and around the world. Foreign observations concentrated in the Middle East and...

  5. Use of Framingham risk score and new biomarkers to predict cardiovascular mortality in older people: population based observational cohort study

    OpenAIRE

    de Ruijter, Wouter; Westendorp, Rudi G. J.; Assendelft, Willem J J; Wendy P J den Elzen; Anton J M de Craen; le Cessie, Saskia; Gussekloo, Jacobijn

    2009-01-01

    Objectives To investigate the performance of classic risk factors, and of some new biomarkers, in predicting cardiovascular mortality in very old people from the general population with no history of cardiovascular disease. Design The Leiden 85-plus Study (1997-2004) is an observational prospective cohort study with 5 years of follow-up. Setting General population of the city of Leiden, the Netherlands. Participants Population based sample of participants aged 85 years (215 women and 87 men) ...

  6. Immigrants’ use of emergency primary health care in Norway: a registry-based observational study

    Directory of Open Access Journals (Sweden)

    Sandvik Hogne

    2012-09-01

    Full Text Available Abstract Background Emigrants are often a selected sample and in good health, but migration can have deleterious effects on health. Many immigrant groups report poor health and increased use of health services, and it is often claimed that they tend to use emergency primary health care (EPHC services for non-urgent purposes. The aim of the present study was to analyse immigrants’ use of EPHC, and to analyse variations according to country of origin, reason for immigration, and length of stay in Norway. Methods We conducted a registry based study of all immigrants to Norway, and a subsample of immigrants from Poland, Germany, Iraq and Somalia, and compared them with native Norwegians. The material comprised all electronic compensation claims for EPHC in Norway during 2008. We calculated total contact rates, contact rates for selected diagnostic groups and for services given during consultations. Adjustments for a series of socio-demographic and socio-economic variables were done by multiple logistic regression analyses. Results Immigrants as a whole had a lower contact rate than native Norwegians (23.7% versus 27.4%. Total contact rates for Polish and German immigrants (mostly work immigrants were 11.9% and 7.0%, but for Somalis and Iraqis (mostly asylum seekers 31.8% and 33.6%. Half of all contacts for Somalis and Iraqis were for non-specific pain, and they had relatively more of their contacts during night than other groups. Immigrants’ rates of psychiatric diagnoses were low, but increased with length of stay in Norway. Work immigrants suffered less from respiratory and gastrointestinal infections, but had more injuries and higher need for sickness certification. All immigrant groups, except Germans, were more often given a sickness certificate than native Norwegians. Use of interpreter was reduced with increasing length of stay. All immigrant groups had an increased need for long consultations, while laboratory tests were most often used

  7. Study on Chaotic Fault Tolerant Synchronization Control Based on Adaptive Observer

    Directory of Open Access Journals (Sweden)

    Dongming Chen

    2014-01-01

    Full Text Available Aiming at the abrupt faults of the chaotic system, an adaptive observer is proposed to trace the states of the master system. The sufficient conditions for synchronization of such chaotic systems are also derived. Then the feasibility and effectiveness of the proposed method are illustrated via numerical simulations of chaotic Chen system. Finally, the proposed synchronization schemes are applied to secure communication system successfully. The experimental results demonstrate that the employed observer can manage real-time fault diagnosis and parameter identification as well as states tracing of the master system, and so the synchronization of master system and slave system is achieved.

  8. Study on the triggering process of solar flares based on Hinode/SOT observations

    International Nuclear Information System (INIS)

    We investigated four major solar flare events that occurred in active regions NOAA 10930 (2006 December 13 and 14) and NOAA 11158 (2011 February 13 and 15) by using data observed by the Solar Optical Telescope on board the Hinode satellite. To reveal the trigger mechanism of solar flares, we analyzed the spatio-temporal correlation between the detailed magnetic field structure and the emission image of the Ca II H line at the central part of flaring regions for several hours prior to the onset of the flares. In all the flare events, we observed that the magnetic shear angle in the flaring regions exceeded 70°, as well as that characteristic magnetic disturbances developed at the centers of flaring regions in the pre-flare phase. These magnetic disturbances can be classified into two groups depending on the structure of their magnetic polarity inversion lines; the so-called opposite-polarity and reversed-shear magnetic field recently proposed by our group, although the magnetic disturbance in one event of the four samples is too subtle to clearly recognize the detailed structure. The result suggests that some major solar flares are triggered by rather small magnetic disturbances. We also show that the critical size of the flare-trigger field varies among flare events and briefly discuss how the flare-trigger process depends on the evolution of active regions.

  9. Health Care Consumption during Pregnancy in relation to Maternal Body Mass Index : A Swedish Population Based Observational Study

    OpenAIRE

    Lindholm, Elisabeth S.; Daniel Altman; Margareta Norman; Marie Blomberg

    2015-01-01

    Objective. To assess whether antenatal health care consumption is associated with maternal body mass index (BMI). Design. A register based observational study. Methods. The Swedish Medical Birth Register, the Maternal Health Care Register, and the Inpatient Register were used to determine antenatal health care consumption according to BMI categories for primiparous women with singleton pregnancies, from 2006 to 2008, n = 71,638. Pairwise comparisons among BMI groups are obtained post hoc by T...

  10. Viral infections, prevalence and costs: A5-year, hospital based, retrospective observational study in shiraz, iran

    International Nuclear Information System (INIS)

    Many patients suffering from viral infections attend to health care centers. Data gathered from viral infections is limited to specific cases such as AIDS, viral hepatitis and Influenza. There is a significant lack of reliable documentation about other viral infections. In this study the prevalence and related costs of viral infections in hospitals of Shiraz University of Medical Sciences were reviewed. In this cross-sectional study the data were extracted from files of 1319 patients with viral infection admitted in two university hospitals during a five year period (1999-2004). The frequencies of different viral infections along with their demographic data were analyzed. The mean age of the patients was 29.24 with the range of 90 years. Hospitalization days were 8636 in 40 different wards in two hospitals. US$ 30.84 was the daily mean cost for each admitted patient. Viral meningitis was most frequent (14.2%) and 8.4% of patients died during hospitalization. This study confirms the necessity of expanding management programs for viral infections especially hepatitis B in youths in Iran. Unspecified viral infections cost much more than specified viral diseases. Viral infection costs can be reduced by finding more sensitive and specific diagnostic methods. (author)

  11. Family-Based Behavioural Intervention Program for Obese Children: An Observational Study of Child and Parent Lifestyle Interpretations

    OpenAIRE

    Teder, Marie; Mörelius, Eva-Lotte; Nordwall, Maria; Bolme, Per; Ekberg, Joakim; Wilhelm, Elisabeth; Timpka, Toomas

    2013-01-01

    Background Family-based behavioural intervention programs (FBIPs) against childhood obesity have shown promising results, but the mediating mechanisms have not been identified. The aim of this study was to examine changes in obese childreńs lifestyle habits during a 2-year FBIP according to their own and parents’ reports, the concordance between these reports and the correlations to change in post-intervention z-BMI. Methods An observational study of 26 children (8.3–12.0 years) and their par...

  12. A long-term study of low-latitude ionospheric irregularities at African longitudes by ground-based GPS observations

    International Nuclear Information System (INIS)

    Complete text of publication follows. This study investigated a long-term climatology of nocturnal low-latitude F-region irregularities at African longitudes by ground-based observations of the global positioning system (GPS). The results of irregularity occurrence obtained by using GPS phase fluctuations showed that in both East and Middle Africa (1) the distributions of the occurrence of ionospheric irregularities are two-peak patterns which peak in equinox months with obviously shallow/deep dips in June/December solstice months during high solar activity period, and however, with slightly shallow/deep dips in June/December solstice months during low solar activity period; (2) the occurrence rates of irregularities are positively dependent on solar activity; (3) during some years of high solar activity period, the occurrence rates of moderate irregularities in June solstice months can surpass those in equinox months (especially in Middle Africa) although the occurrence rates of strong irregularities still achieve maxima in equinox months. Likewise, in West Africa, the occurrence rate of irregularities is also positively dependent on solar activity and reaches maximum in equinox months. However, the occurrence rate in December solstice is larger than that in June solstice, which is quite different from the results in both East and Middle Africa. There is an interesting longitudinal effect in solstice occurrences of irregularities, that is, ionospheric irregularities develop easier in June solstice months in both East and Middle Africa but develop easier in December solstice months in West Africa during high solar activity period. The results obtained by ground-based GPS observations are similar to those obtained by previous satellite-based observations.

  13. The Clinical Research Center for Depression Study: Baseline Characteristics of a Korean Long-Term Hospital-Based Observational Collaborative Prospective Cohort Study

    OpenAIRE

    Kim, Tae-Suk; Jeong, Seung Hee; Kim, Jung-Bum; Lee, Min-Soo; Kim, Jae-Min; Yim, Hyeon-Woo; Jun, Tae-Youn

    2010-01-01

    Objective The Clinical Research Center for Depression (CRESCEND) study is a 9-year observational collaborative prospective cohort study for the clinical outcomes in participants with depressive disorders in Korea. In this study, we examined the baseline characteristics of the depressive participants as the hospital-based cohort. Methods Participants were assessed using various instruments including the Clinical Global Impression scale, 17-item Hamilton Depression Rating Scale (HDRS-17), Hamil...

  14. SELF-LEARNING METHODS PREFERRED BY SECOND YEAR MBBS STUDENTS IN UNDERSTANDING PHARMACOLOGY: AN OBSERVATIONAL QUESTIONNAIRE BASED STUDY

    Directory of Open Access Journals (Sweden)

    Padmanabha Thiruganahalli

    2016-05-01

    Full Text Available BACKGROUND AIMS To evaluate the self-learning habits via different learning styles which can influence and be a useful indicator for potential learning performance of an individual. MATERIAL & METHODS Observational questionnaire based study to evaluate self-learning habits among Second year undergraduates, Adichunchanagiri Institute of Medical Sciences, B. G. Nagara, Mandya, Karnataka. RESULTS 50.55% had an opinion that Problem Based Learning (PBL stimulates self-directed learning. 76.92% were said self-learning process should include both LBL (Literature Based Learning & PBL together. Majority of the students said the learning is boring through Literature based learning. And 59.34% said topic could be more interesting & less boring if both were included according to the situation. 84.62% said self-learning through LBL is more time consuming over PBL. 80% preferred to integrate all the subjects. 46.45% said it is better to start the PBL early in the 1 st year itself. CONCLUSION 'Learning to learn' is a crucial skill. Continued additions can lead to “Curriculum Hypertrophy”, emphasising on "Lifelong learning” skills in students & who develop such skills will be equipped for whatever the future holds and will keep up to date when they are no longer on formal training programs

  15. ViewDEX 2.0: a Java-based DICOM-compatible software for observer performance studies

    Science.gov (United States)

    Håkansson, Markus; Svensson, Sune; Zachrisson, Sara; Svalkvist, Angelica; Båth, Magnus; Månsson, Lars Gunnar

    2009-02-01

    ViewDEX (Viewer for Digital Evaluation of X-ray images) is a Java-based DICOM-compatible software tool for observer performance studies that can be used to display medical images with simultaneous registration of the observer's response. The current release, ViewDEX 2.0 is a development of ViewDEX 1.0, which was released in 2007. Both versions are designed to run in a Java environment and do not require any special installation. For example, the program can be located on a memory stick or stand alone hard drive and be run from there. ViewDEX is managed and configured by editing property files, which are plain text files where users, tasks (questions, definitions, etc.) and functionality (WW/WL, PAN, ZOOM, etc.) are defined. ViewDEX reads all common DICOM image formats and the images can be stored in any location connected to the computer. ViewDEX 2.0 is designed so that the user in a simple way can alter if the questions presented to the observers are related to localization or not, enabling e.g. free-response ROC, standard ROC and visual grading studies, as well as combinations of these, to be conducted in a fast and efficient way. The software can also be used for bench marking and for educational purposes. The results from each observer are saved in a log file, which can be exported for further analysis. The software is freely available for non-commercial purposes.

  16. A simulation study of the ensemble-based data assimilation of satellite-borne lidar aerosol observations

    OpenAIRE

    Sekiyama, T. T.; T. Y. Tanaka; T. Miyoshi

    2012-01-01

    A four-dimensional ensemble-based data assimilation system was assessed by observing system simulation experiments (OSSEs), in which the CALIPSO satellite was emulated via simulated satellite-borne lidar aerosol observations. Its performance over athree-month period was validated according to the Method for Object-based Diagnostic Evaluation (MODE), using aerosol optical thickness (AOT) distributions in East Asia as the objects of analysis. Consequently, this data a...

  17. Object-based change detection in rapid urbanization regions with remotely sensed observations: a case study of Shenzhen, China

    Science.gov (United States)

    He, Lihuang; Dong, Guihua; Wang, Wei-Min; Yang, Lijun; Liang, Hong

    2013-10-01

    China, the most populous country on Earth, has experienced rapid urbanization which is one of the main causes of many environmental and ecological problems. Therefore, the monitoring of rapid urbanization regions and the environment is of critical importance for their sustainable development. In this study, the object-based classification is employed to detect the change of land cover in Shenzhen, which is located in South China and has been urbanized rapidly in recent three decades. First, four Landsat TM images, which were acquired on 1990, 2000 and 2010, respectively, are selected from the image database. Atmospheric corrections are conducted on these images with improved dark-object subtraction technique and surface meteorological observations. Geometric correction is processed with ground control points derived from topographic maps. Second, a region growing multi-resolution segmentation and a soft nearest neighbour classifier are used to finish object-based classification. After analyzing the fraction of difference classes over time series, we conclude that the comparison of derived land cover classes with socio-economic statistics demonstrates the strong positive correlation between built-up classes and urban population as well as gross GDP and GDPs in second and tertiary industries. Two different mechanisms of urbanization, namely new land development and redevelopment, are revealed. Consequently, we found that, the districts of Shenzhen were urbanized through different mechanisms.

  18. Routine delivery of artemisinin-based combination treatment at fixed health facilities reduces malaria prevalence in Tanzania: an observational study

    Directory of Open Access Journals (Sweden)

    Khatib Rashid A

    2012-04-01

    Full Text Available Abstract Background Artemisinin-based combination therapy (ACT has been promoted as a means to reduce malaria transmission due to their ability to kill both asexual blood stages of malaria parasites, which sustain infections over long periods and the immature derived sexual stages responsible for infecting mosquitoes and onward transmission. Early studies reported a temporal association between ACT introduction and reduced malaria transmission in a number of ecological settings. However, these reports have come from areas with low to moderate malaria transmission, been confounded by the presence of other interventions or environmental changes that may have reduced malaria transmission, and have not included a comparison group without ACT. This report presents results from the first large-scale observational study to assess the impact of case management with ACT on population-level measures of malaria endemicity in an area with intense transmission where the benefits of effective infection clearance might be compromised by frequent and repeated re-infection. Methods A pre-post observational study with a non-randomized comparison group was conducted at two sites in Tanzania. Both sites used sulphadoxine-pyrimethamine (SP monotherapy as a first-line anti-malarial from mid-2001 through 2002. In 2003, the ACT, artesunate (AS co-administered with SP (AS + SP, was introduced in all fixed health facilities in the intervention site, including both public and registered non-governmental facilities. Population-level prevalence of Plasmodium falciparum asexual parasitaemia and gametocytaemia were assessed using light microscopy from samples collected during representative household surveys in 2001, 2002, 2004, 2005 and 2006. Findings Among 37,309 observations included in the analysis, annual asexual parasitaemia prevalence in persons of all ages ranged from 11% to 28% and gametocytaemia prevalence ranged from Interpretation The introduction of ACT at

  19. A MiniReview of the Use of Hospital-based Databases in Observational Inpatient Studies of Drugs

    DEFF Research Database (Denmark)

    Larsen, Michael Due; Cars, Thomas; Hallas, Jesper

    2013-01-01

    data. Twenty studies were selected and discussed to illustrate the diversity of inpatient pharmacoepidemiological studies. Hospital-based databases had mainly been used for drug utilization studies and research in adverse drug reactions.Five studies within comparative effectiveness were found...... pharmacoepidemiological studies in hospital settings and the underlying databases to provide an overview of research questions addressed by such databases. The studies were retrieved by chain searching. We included pharmacoepidemiological studies in hospital settings containing data on inpatient drug use. Twelve...

  20. Digital Elevation Models of the Earth derived from space-based observations: Advances and potential for geomorphological studies

    Science.gov (United States)

    Mouratidis, Antonios

    2013-04-01

    Digital Elevation Models (DEMs) are an inherently interdisciplinary topic, both due to their production and validation methods, as well as their significance for numerous disciplines. The most utilized contemporary topographic datasets worldwide are those of global DEMs. Several space-based sources have been used for the production of (almost) global DEMs, namely satellite Synthetic Aperture Radar (SAR) Interferometry/InSAR, stereoscopy of multispectral satellite images and altimetry, producing several versions of autonomous or mixed products (i.e. SRTM, ACE, ASTER-GDEM). Complementary space-based observations, such as those of Global Navigation Satellite Systems (GNSS), are also used, mainly for validation purposes. The apparent positive impact of these elevation datasets so far has been consolidated by the plethora of related scientific, civil and military applications. Topography is a prominent element for almost all Earth sciences, but in Geomorphology it is even more fundamental. In geomorphological studies, elevation data and thus DEMs can be extensively used for the extraction of both qualitative and quantitative information, such as relief classification, determination of slope and slope orientation, delineation of drainage basins, extraction of drainage networks and much more. Global DEMs are constantly becoming finer, i.e. of higher spatial resolution and more "sensitive" to elevation changes, i.e. of higher vertical accuracy and these progresses are undoubtedly considered as a major breakthrough, each time a new improved global DEM is released. Nevertheless, for Geomorphology in particular, if not already there, we are close to the point in time, where the need for discrimination between DSM (Digital Surface Model) and DTM (Digital Terrain Model) is becoming critical; if the distinction between vegetation and man-made structures on one side (DSM), and actual terrain elevation on the other side (DTM) cannot be made, then, in many cases, any further

  1. Cardiovascular risk with non-steroidal anti-inflammatory drugs: systematic review of population-based controlled observational studies.

    Directory of Open Access Journals (Sweden)

    Patricia McGettigan

    2011-09-01

    Full Text Available BACKGROUND: Randomised trials have highlighted the cardiovascular risks of non-steroidal anti-inflammatory drugs (NSAIDs in high doses and sometimes atypical settings. Here, we provide estimates of the comparative risks with individual NSAIDs at typical doses in community settings. METHODS AND FINDINGS: We performed a systematic review of community-based controlled observational studies. We conducted comprehensive literature searches, extracted adjusted relative risk (RR estimates, and pooled the estimates for major cardiovascular events associated with use of individual NSAIDs, in different doses, and in populations with low and high background risks of cardiovascular events. We also compared individual drugs in pair-wise (within study analyses, generating ratios of RRs (RRRs. Thirty case-control studies included 184,946 cardiovascular events, and 21 cohort studies described outcomes in >2.7 million exposed individuals. Of the extensively studied drugs (ten or more studies, the highest overall risks were seen with rofecoxib, 1.45 (95% CI 1.33, 1.59, and diclofenac, 1.40 (1.27, 1.55, and the lowest with ibuprofen, 1.18 (1.11, 1.25, and naproxen, 1.09 (1.02, 1.16. In a sub-set of studies, risk was elevated with low doses of rofecoxib, 1.37 (1.20, 1.57, celecoxib, 1.26 (1.09, 1.47, and diclofenac, 1.22 (1.12, 1.33, and rose in each case with higher doses. Ibuprofen risk was seen only with higher doses. Naproxen was risk-neutral at all doses. Of the less studied drugs etoricoxib, 2.05 (1.45, 2.88, etodolac, 1.55 (1.28, 1.87, and indomethacin, 1.30 (1.19, 1.41, had the highest risks. In pair-wise comparisons, etoricoxib had a higher RR than ibuprofen, RRR = 1.68 (99% CI 1.14, 2.49, and naproxen, RRR = 1.75 (1.16, 2.64; etodolac was not significantly different from naproxen and ibuprofen. Naproxen had a significantly lower risk than ibuprofen, RRR = 0.92 (0.87, 0.99. RR estimates were constant with different background risks for

  2. Short term adherence tool predicts failure on second line protease inhibitor-based antiretroviral therapy: an observational cohort study

    OpenAIRE

    Court, Richard; Leisegang, Rory; Stewart, Annemie; Sunpath, Henry; Murphy, Richard; Winternheimer, Philip; Ally, Mashuda; Maartens, Gary

    2014-01-01

    Background Most patients who experience virologic failure (VF) on second line antiretroviral therapy (ART) in low-middle income countries fail due to poor adherence rather than antiretroviral resistance. A simple adherence tool designed to detect VF would conserve resources by rationally limiting need for viral load (VL) testing and, in those countries with access to third line ART, the need for resistance testing. Methods We conducted an observational cohort study of patients who initiated s...

  3. Association between Perceived Value and Self-Medication with Antibiotics: An Observational Study Based on Health Belief Model Theory

    OpenAIRE

    Annisa N. Insany; Dika P. Destiani; Anwar Sani; Lilik Sabdaningtyas; Ivan S. Pradipta

    2015-01-01

    High prevalence of self medication with antibiotics can increase the probability of irrational use of antibiotics which may lead antibiotics resistance. Thus, shifting of behavior is required to minimize the irrational use of antibiotics. This study was aimed to determine the association between public perceived value and self-medication with antibiotics which can be used to develop an intervention model in order to reduce the practice of self-medication with antibiotics. An observational stu...

  4. Study on team evaluation (5). On application of behavior observation-based teamwork evaluation sheet for power plant operator team

    International Nuclear Information System (INIS)

    This report discusses the range of application of the behavior observation-based teamwork evaluation sheet. Under the concept of this method, teamwork evaluation sheet is developed, which assumes a certain single failure (failure of feed water transmitter). The evaluation sheets are applied to evaluate team work of 26 thermal power plant operator teams in combined under abnormal operating conditions of failure of feed water transmitter, feed draft fan or steam flow governor. As a result of ANOVA, it finds that there are no differences between 3 kinds of single failure. In addition, the similar analysis is executed to 3 kinds of multiple failures (steam generator tube rapture, loss of coolant accident and loss of secondary coolant accident) under which 7 PWR nuclear power plant operator teams are evaluated. As a result, ANOVA shows no differences between 3 kinds of multiple failures. These results indicate that a behavior observation-based team work evaluation sheet, which is designed for a certain abnormal condition, is applicable to the abnormal conditions that have the same development of abnormal conditions. (author)

  5. Chemical and physical influences on aerosol activation in liquid clouds: an empirical study based on observations from the Jungfraujoch, Switzerland

    Directory of Open Access Journals (Sweden)

    C. R. Hoyle

    2015-06-01

    Full Text Available A simple empirical model to predict the number of aerosols which activate to form cloud droplets in a warm, free tropospheric cloud has been established, based on data from four summertime Cloud and Aerosol Characterisation Experiments (CLACE campaigns at the Jungfraujoch (JFJ. It is shown that 76% of the observed variance in droplet numbers can be represented by a model accounting only for the number of potential CCN (defined as number of particles larger than 90 nm in diameter, while the mean errors in the model representation may be reduced by the addition of further explanatory variables, such as the mixing ratios of O3, CO and the height of the measurements above cloud base. The model has similar ability to represent the observed droplet numbers in each of the individual years, as well as for the two predominant local wind directions at the JFJ (north west and south east. Given the central European location of the JFJ, with air masses in summer being representative of the free troposphere with regular boundary layer in-mixing via convection, we expect that this model is applicable to warm, free tropospheric clouds over the European continent.

  6. Competing-Risks Mortality After Radiotherapy vs. Observation for Localized Prostate Cancer: A Population-based Study

    International Nuclear Information System (INIS)

    Purpose: Contemporary patients with localized prostate cancer (PCa) are more frequently treated with radiotherapy. However, there are limited data on the effect of this treatment on cancer-specific mortality (CSM). Our objective was to test the relationship between radiotherapy and survival in men with localized PCa and compare it with those treated with observation. Methods: A population-based cohort identified 68,797 men with cT1–T2 PCa treated with radiotherapy or observation between the years 1992 and 2005. Propensity-score matching was used to minimize potential bias related to treatment assignment. Competing-risks analyses tested the effect of treatment type (radiotherapy vs. observation) on CSM, after accounting to other-cause mortality. All analyses were carried out within PCa risk, baseline comorbidity status, and age groups. Results: Radiotherapy was associated with more favorable 10-year CSM rates than observation in patients with high-risk PCa (8.8 vs. 14.4%, hazard ratio [HR]: 0.59, 95% confidence interval [CI]: 0.50–0.68). Conversely, the beneficial effect of radiotherapy on CSM was not evident in patients with low-intermediate risk PCa (3.7 vs. 4.1%, HR: 0.91, 95% CI: 0.80–1.04). Radiotherapy was beneficial in elderly patients (5.6 vs. 7.3%, HR: 0.70, 95% CI: 0.59–0.80). Moreover, it was associated with improved CSM rates among patients with no comorbidities (5.7 vs. 6.5%, HR: 0.81, 95% CI: 0.67–0.98), one comorbidity (4.6 vs. 6.0%, HR: 0.87, 95% CI: 0.75–0.99), and more than two comorbidities (4.2 vs. 5.0%, HR: 0.79, 95% CI: 0.65–0.96). Conclusions: Radiotherapy substantially improves CSM in patients with high-risk PCa, with little or no benefit in patients with low-/intermediate-risk PCa relative to observation. These findings must be interpreted within the context of the limitations of observational data.

  7. Ensemble-based approximation of observation impact using an observation-based verification metric

    OpenAIRE

    Sommer, Matthias; Weissmann, Martin

    2016-01-01

    Knowledge on the contribution of observations to forecast accuracy is crucial for the refinement of observing and data assimilation systems. Several recent publications highlighted the benefits of efficiently approximating this observation impact using adjoint methods or ensembles. This study proposes a modification of an existing method for computing observation impact in an ensemble-based data assimilation and forecasting system and applies the method to a pre-operational, convective-scale ...

  8. A Ground Observation Based Climatology and Forecasting of Winter Fog: Study over Ghaziabad, National Capital Region, India

    Science.gov (United States)

    Srivastava, S. K., Sr.; Sharma, D. A.; Sachdeva, K.

    2015-12-01

    Long term ground observations (1971-2010) have been analyzed over Ghaziabad city, National Capital Region to understand the characteristics of fog phenomenon and its relevance during winter months. We observed mean maximum fog occurrence during December (~23 days) followed by January (~21 days), November (~20 days), February (~14 days) and October (~11 days) respectively. A remarkable increase has been noticed in fog occurrence during October-to-February in last four decades. During 1971-80 to 2001-2010 the mean frequency of fog occurrence had increased by 205.5% in October month and 50.2% in November month. Similarly, mean frequency of fog occurrence increased by 51%, 97% and 119% during December, January and February respectively over the same period. We observed statistically significant increasing trend in fog occurrence from October-to-February during the study period at 95% confidence level. The magnitude of trend is 0.50, 0.47, 0.30, 0.39 and 0.37 for October, November, December, January and February, respectively. The magnitude of trend is highest in October but the occurrence frequency is highest in December. The forecast values obtained from ARIMA model indicates that the number of fog days is going to increase further during October-to-February in the forthcoming years. The data combined with knowledge of meteorology and topography suggested significant conclusions about increase in the fog events in the near future.

  9. Space-based long-term observation of shrinking grassland habitat: A case-study from central India

    Science.gov (United States)

    Lele, N.; Singh, C. P.; Singh, R. P.; Chauhan, J. S.; Parihar, J. S.

    2015-10-01

    Grassland ecosystem is critical for survival of herbivores and plays an important role in conservation and management of wildlife. These habitats are widely studied for various issues, including biodiversity, biomass assessment, carrying capacity, etc. Woody species ingression in grasslands is one such important aspect that needs critical attention in protected area as this leads to shrinking of grasslands habitat. This study presents a case of Ronda grassland in Kanha National Park - a well-known protected area in India, known for its herbivore diversity and hard-ground Barasingha (Rucervus duvaceli branderi), in particular. Long-term satellite observation for five decades was carried out to understand spatio-temporal changes. Declassified Corona satellite data, aerial photographs along with satellite datasets in the subsequent period were utilised for this study. The study revealed that 88 ha (16% of Ronda and surrounding) have been ingressed during 1962-2011, in and around Ronda grassland of Kanha National Park. Rates of ingression on linear transects were found to be 60-120 m per decade. Field studies and NDVI analysis along the edge of grassland pixels as well as inside region using 1972 as baseline data, indicated woody vegetation replacing area of grassland. It was noted that Butea monosperma is invading more than other species in Ronda grassland, particularly along the stream where moisture availability is higher. Grassland habitats in Kanha are thus shrinking and thus leading to reduction in the area available for herbivore population which has increased in recent years. This can lead to severe impact on carrying capacity of these grasslands.

  10. Correction of atmospheric scattering effects in space-based observations of carbon dioxide: Model study of desert dust aerosol

    International Nuclear Information System (INIS)

    We describe an original methodology for CO2 retrievals using space-based measurements of reflected sunlight spectra. The effects of optical-path modification by aerosols were considered in terms of photon path-length statistics. First, the general approach was verified using a representative set of photon trajectories produced by the Monte Carlo technique. This method enabled accurate consideration of optical-path modification by aerosols and was effective in CO2 retrievals if aerosol optical properties were assumed. The next approach involved a limited number of parameters that describe the photon path-length distribution function (PPDF) and which were retrieved simultaneously with the CO2 amount. This approach was efficient under conditions of strong path modification by desert dust aerosol. The retrieval procedure included the following: estimation of PPDF parameters from radiance spectra in the O2 A-band; the necessary correction to use these estimated parameters in the 1.6-μm band; and, finally, CO2 retrievals from the 1.6-μm band. The procedure was verified by numerical simulations using an independent radiative transfer approach to produce radiance spectra expected for the Greenhouse Gases Observing Satellite (GOSAT) sensor

  11. Frequency of GP communication addressing the patient's resources and coping strategies in medical interviews: a video-based observational study

    Directory of Open Access Journals (Sweden)

    Finset Arnstein

    2009-07-01

    Full Text Available Abstract Background There is increasing focus on patient-centred communicative approaches in medical consultations, but few studies have shown the extent to which patients' positive coping strategies and psychological assets are addressed by general practitioners (GPs on a regular day at the office. This study measures the frequency of GPs' use of questions and comments addressing their patients' coping strategies or resources. Methods Twenty-four GPs were video-recorded in 145 consultations. The consultations were coded using a modified version of the Roter Interaction Analysis System. In this study, we also developed four additional coding categories based on cognitive therapy and solution-focused therapy: attribution, resources, coping, and solution-focused techniques. The reliability between coders was established, a factor analysis was applied to test the relationship between the communication categories, and a tentative validating exercise was performed by reversed coding. Results Cohen's kappa was 0.52 between coders. Only 2% of the utterances could be categorized as resource or coping oriented. Six GPs contributed 59% of these utterances. The factor analysis identified two factors, one task oriented and one patient oriented. Conclusion The frequency of communication about coping and resources was very low. Communication skills training for GPs in this field is required. Further validating studies of this kind of measurement tool are warranted.

  12. Systematic study of intermediate-scale structures of equatorial plasma irregularities in the ionosphere based on CHAMP observations

    Directory of Open Access Journals (Sweden)

    Hermann eLühr

    2014-03-01

    Full Text Available Equatorial spread-F ionospheric plasma irregularities on the night-side, commonly called equatorial plasma bubbles (EPB, include electron density variations over a wide range of spatial scales. Here we focus on intermediate-scale structures ranging from 100 m to 10 km, which play an important role in the evolution of EPBs. High-resolution CHAMP magnetic field measurements sampled along north-south track at 50 Hz are interpreted in terms of diamagnetic effect for illustrating the details of electron density variations. We provide the first comprehensive study on intermediate-scale density structures associated with EPBs, covering a whole solar cycle from 2000 to 2010. The large number of detected events, almost 9000, allows us to draw a detailed picture of the plasma fine structure. The occurrence of intermediate-scale events is strongly favoured by high solar flux. During times of F10.7 < 100 sfu practically no events were observed. The longitudinal distribution of our events with respect to season or local time agrees well with that of the EPBs, qualifying the fine structure as a common feature, but the occurrence rates are smaller by a factor of 4 during the period 2000-2005. Largest amplitude electron density variations appear at the poleward boundaries of plasma bubbles. Above the dip-equator recorded amplitudes are small and fall commonly below our resolution. Events can generally be found at local times between 19 and 24 LT, with a peak lasting from 20 to 22 LT. The signal spectrum can be approximated by a power law. Over the frequency range 1 – 25 Hz we observe spectral indices between -1.4 and -2.6 with peak occurrence rates around -1.9. There is a weak dependence observed of the spectral index on local time. Towards later hours the spectrum becomes shallower. Similarly for the latitude dependence, there is a preference of shallower spectra for latitudes poleward of the ionisation anomaly crest. Our data suggest that the generation of

  13. Recurrent differentiated thyroid cancer: towards personalized treatment based on evaluation of tumor characteristics with PET (THYROPET Study): study protocol of a multicenter observational cohort study

    International Nuclear Information System (INIS)

    After initial treatment of differentiated thyroid carcinoma (DTC) patients are followed with thyroglobulin (Tg) measurements to detect recurrences. In case of elevated levels of Tg and negative neck ultrasonography, patients are treated 'blindly' with Iodine-131 (131I). However, in up to 50% of patients, the post-therapy scan reveals no 131I-targeting of tumor lesions. Such patients derive no benefit from the blind therapy but are exposed to its toxicity. Alternatively, iodine-124 (124I) Positron Emission Tomography/Computed Tomography (PET/CT) has become available to visualize DTC lesions and without toxicity. In addition to this, 18F-fluorodeoxyglucose (18F-FDG) PET/CT detects the recurrent DTC phenotype, which lost the capacity to accumulate iodine. Taken together, the combination of 124I and 18F-FDG PET/CT has potential to stratify patients for treatment with 131I. In a multicenter prospective observational cohort study the hypothesis that the combination of 124I and 18F-FDG PET/CT can avoid futile 131I treatments in patients planned for ‘blind’ therapy with 131I, is tested. One hundred patients planned for 131I undergo both 124I and 18F-FDG PET/CT after rhTSH stimulation. Independent of the outcome of the scans, all patients will subsequently receive, after thyroid hormone withdrawal, the 131I therapy. The post 131I therapeutic scintigraphy is compared with the outcome of the 124I and 18F-FDG PET/CT in order to evaluate the diagnostic value of the combined PET modalities. This study primary aims to reduce the number of futile 131I therapies. Secondary aims are the nationwide introduction of 124I PET/CT by a quality assurance and quality control (QA/QC) program, to correlate imaging outcome with histopathological features, to compare 124I PET/CT after rhTSH and after withdrawal of thyroid hormone, and to compare 124I and 131I dosimetry. This study aims to evaluate the potential value of the combination of 124I and 18F-FDG PET/CT in the prevention

  14. Observational Studies: Matching or Regression?

    Science.gov (United States)

    Brazauskas, Ruta; Logan, Brent R

    2016-03-01

    In observational studies with an aim of assessing treatment effect or comparing groups of patients, several approaches could be used. Often, baseline characteristics of patients may be imbalanced between groups, and adjustments are needed to account for this. It can be accomplished either via appropriate regression modeling or, alternatively, by conducting a matched pairs study. The latter is often chosen because it makes groups appear to be comparable. In this article we considered these 2 options in terms of their ability to detect a treatment effect in time-to-event studies. Our investigation shows that a Cox regression model applied to the entire cohort is often a more powerful tool in detecting treatment effect as compared with a matched study. Real data from a hematopoietic cell transplantation study is used as an example. PMID:26712591

  15. Observational Study of Travelers' Diarrhea.

    Science.gov (United States)

    Meuris

    1995-03-01

    Background: European air travelers returning from Algeria, Egypt, Mexico, Morocco, and Tunisia were interviewed about their experience of travelers' diseases upon arrival in Brussels. Diarrhea was mentioned by 37% of the adults and 27% of the children. These subjects were questioned about the types of measures taken, type and duration of drug treatment (if any), and about duration of diarrhea and side effects experienced. Methods: Final analysis was performed based on 2160 interviews. The largest proportion of diarrhea was reported in the age group 15-24 years (46%). Results: The majority of the 2160 subjects had opted for drug treatment (81%): 927 subjects for loperamide alone, 235 for loperamide in combination with nifuroxazide, and 178 for nifuroxazide alone. Other drugs had been used less frequently. The median time to recovery was 2.4 days with loperamide compared to 3.2 days with nifuroxazide and to 3.4 days for the no-treatment group. Conclusions: A stratification of the results by severity of the diarrhea suggests a rank of antidiarrheal potency as follows: loperamide > nifuroxazide > no-drug treatment. The side effect with the highest incidence was constipation (2.4% with loperamide). (J Travel Med 2:11-15, 1995) Travelers' diarrhea is usually defined as the passage of at least three unformed stools per day or any number of such stools when accompanied by fever, abdominal cramping, or vomiting. The definition may be broadened to include more trivial bowel disturbance.1,2 The duration of this self-limited disease generally is 3 to 5 days. Medical intervention aims at shortening the duration of disease, thus allowing the sufferer to resume his or her usual activities at an early stage. A shortened period of recovery to physical well-being has obvious favorable economic implications if the traveler is on business and may help the maintenance of a desired level of quality of life while a traveler is on holiday. An observational study of various medical

  16. Verbal and physical violence towards hospital- and community-based physicians in the Negev: an observational study

    Directory of Open Access Journals (Sweden)

    Freud Tami

    2005-08-01

    Full Text Available Abstract Background Over recent years there has been an increasing prevalence of verbal and physical violence in Israel, including in the work place. Physicians are exposed to violence in hospitals and in the community. The objective was to characterize acts of verbal and physical violence towards hospital- and community-based physicians. Methods A convenience sample of physicians working in the hospital and community completed an anonymous questionnaire about their experience with violence. Data collection took place between November 2001 and July 2002. One hundred seventy seven physicians participated in the study, 95 from the hospital and 82 from community clinics. The community sample included general physicians, pediatricians, specialists and residents. Results Ninety-nine physicians (56% reported at least one act of verbal violence and 16 physicians (9% reported exposure to at least one act of physical violence during the previous year. Fifty-one hospital physicians (53.7% were exposed to verbal violence and 9 (9.5% to physical violence. Forty-eight community physicians (58.5% were exposed to verbal violence and 7 (8.5% to physical violence. Seventeen community physicians (36.2% compared to eleven hospital physicians (17.2% said that the violence had a negative impact on their family and on their quality of life (p Conclusion Verbal and/or physical violence against physicians is common in both the hospital and in community clinics. The impatience that accompanies waiting times may have a cultural element. Shortening waiting times and providing more information to patients and families could reduce the rate of violence, but a cultural change may also be required.

  17. Involvement in emergency situations by primary care doctors on-call in Norway - a prospective population-based observational study

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    Hunskaar Steinar

    2010-03-01

    Full Text Available Abstract Background Primary care doctors on-call in the emergency primary health care services in Norway are, together with the ambulances, the primary resources for handling emergencies outside hospitals. There is a lack of reliable data for Norway on how often the primary care doctors are alerted and on their responses in the most urgent emergency cases. The aim of this study was to investigate how doctors on-call are involved in red responses (highest priority, using three different emergency medical communication centres (EMCC as catchment area for a prospective population-based study. Methods In the period from October to December 2007 three dispatch centres covering approximately 816 000 inhabitants prospectively recorded all acute emergency cases. Ambulance records, air ambulance records and records from the doctors on-call were collected. NACA score was used to define the severity of the emergencies. Results 5 105 cases were classified as red responses during the period. We have complete basic recordings (AMIS forms from all and resaved ambulance records, air ambulance records and records from doctors on-call in 89% of the cases. Ambulances were alerted in 96% and doctors on-call in 47% of the cases, but there were large differences between the three EMCCs. Doctors on-call responded with call-out in 42% of the alerted cases. 28% of all patients were taken to a casualty clinic, 46% were admitted to hospital by a doctor and 24% were taken directly to hospital by ambulances. In total, primary care doctors on-call took active part in 42% of all red response cases, and together with GPs' daytime activity the primary health care services were involved in 50% of the cases. 29% of the cases were classified as life-threatening. Call-out by doctors on-call were found to be more frequent in life-threatening situations compared with not life-threatening situations. Conclusion Doctors on-call and GPs on daytime were involved in half of all red

  18. Ways of learning: Observational studies versus experiments

    Science.gov (United States)

    Shaffer, T.L.; Johnson, D.H.

    2008-01-01

    Manipulative experimentation that features random assignment of treatments, replication, and controls is an effective way to determine causal relationships. Wildlife ecologists, however, often must take a more passive approach to investigating causality. Their observational studies lack one or more of the 3 cornerstones of experimentation: controls, randomization, and replication. Although an observational study can be analyzed similarly to an experiment, one is less certain that the presumed treatment actually caused the observed response. Because the investigator does not actively manipulate the system, the chance that something other than the treatment caused the observed results is increased. We reviewed observational studies and contrasted them with experiments and, to a lesser extent, sample surveys. We identified features that distinguish each method of learning and illustrate or discuss some complications that may arise when analyzing results of observational studies. Findings from observational studies are prone to bias. Investigators can reduce the chance of reaching erroneous conclusions by formulating a priori hypotheses that can be pursued multiple ways and by evaluating the sensitivity of study conclusions to biases of various magnitudes. In the end, however, professional judgment that considers all available evidence is necessary to render a decision regarding causality based on observational studies.

  19. Observation, Sherlock Holmes, and Evidence Based Medicine.

    Science.gov (United States)

    Osborn, John

    2002-01-01

    Sir Arthur Conan Doyle, the creator of the fictional detective Sherlock Holmes, studied medicine at the University of Edinburgh between 1876 and 1881 under Doctor Joseph Bell who emphasised in his teaching the importance of observation, deduction and evidence. Sherlock Holmes was modelled on Joseph Bell. The modern notions of Evidence Based Medicine (EBM) are not new. A very brief indication of some of the history of EBM is presented including a discussion of the important and usually overlooked contribution of statisticians to the Popperian philosophy of EBM. PMID:14509997

  20. A Multi-Transition Study of Molecules toward NGC 1068 based on High-Resolution Imaging Observations with ALMA

    CERN Document Server

    Nakajima, Taku; Kohno, Kotaro; Harada, Nanase; Herbst, Eric; Tamura, Yoichi; Izumi, Takuma; Taniguchi, Akio; Tosaki, Tomoka

    2014-01-01

    We present 0.8-mm band molecular images and spectra obtained with the Atacama Large Millimeter/submillimeter Array (ALMA) toward one of the nearest galaxies with an active galactic nucleus (AGN), NGC 1068. Distributions of CO isotopic species ($^{13}$CO and C$^{18}$O) $\\it{J}$ = 3--2, CN $\\it{N}$ = 3--2 and CS $\\it{J}$ = 7--6 are observed toward the circumnuclear disk (CND) and a part of the starburst ring with an angular resolution of $\\sim$1.$^{\\prime\\prime}$3 $\\times$ 1.$^{\\prime\\prime}$2. The physical properties of these molecules and shock-related molecules such as HNCO, CH$_{3}$CN, SO, and CH$_{3}$OH detected in the 3-mm band were estimated using rotation diagrams under the assumption of local thermodynamic equilibrium. The rotational temperatures of the CO isotopic species and the shock-related molecules in the CND are, respectively, 14--22 K and upper limits of 20--40 K. Although the column densities of the CO isotopic species in the CND are only from one-fifth to one-third of that in the starburst ri...

  1. Augmentation index is associated with coronary revascularization in patients with high Framingham risk scores: a hospital-based observational study

    OpenAIRE

    Choi, JoonHyouk; Kim, Song-Yi; Joo, Seung-Jae; Kim, Ki-Seok

    2015-01-01

    Background This study analyzed PWAs in patients with high Framingham risk scores to determine whether PWA is predictive of coronary artery disease (CAD) severity and percutaneous coronary intervention (PCI) treatment. Methods In total, 310 patients were screened due to suspected CAD; 78 were excluded due to PCI history (32), atrial fibrillation (11), or acute myocardial infarction (35). The augmentation index (AIx) was analyzed immediately before coronary angiography. PCI was performed in 73 ...

  2. A Left-Sided Prevalence of Lentigo Maligna: A UK Based Observational Study and Review of the Evidence

    Directory of Open Access Journals (Sweden)

    Mark Gorman

    2015-01-01

    Full Text Available Skin cancer has been shown to present asymmetrically, prevalent on the left side of the body, more so in subtypes of cutaneous melanoma such as lentigo maligna. Biases have been linked to cumulative UV light exposure and automobile driving patterns. Though left-right ratios have previously correlated with the side men or women tend to position themselves or countries drive on, more recent trends indicate a consistent left-sided bias. To clarify reasons for changing trends, a review of the evidence base and LM’s laterality in a UK cohort (99 cases 2000–2011 was conducted for the first time. The strong correlation of left-sided excess, found in both genders (ratios 1.381–1.5, P<0.05  X2 0.841, is congruent with more recent findings. Though evidence indicates that driving position is no longer a risk factor for LM, due most likely to improved car window UV protection, it remains the most commonly attributed cause. Understanding phenomena such as UV lights “scatter effect” or that cumulative exposure may not be a significant risk factor helps rationalize older conclusions that would otherwise appear contradictory. The reasons for left-sided excess remain unclear but may be due to factors requiring further research such as the body’s anatomical/embryological asymmetry.

  3. Return to play after conservative treatment in athletes with symptomatic lumbar disc herniation: a practice-based observational study

    Directory of Open Access Journals (Sweden)

    Jun Iwamoto

    2011-03-01

    Full Text Available Jun Iwamoto1, Yoshihiro Sato2, Tsuyoshi Takeda1, Hideo Matsumoto11Institute for Integrated Sports Medicine, Keio University School of Medicine, Tokyo, Japan; 2Department of Neurology, Mitate Hospital, Fukuoka, JapanAbstract: The purpose of the study was to confirm the short-term outcome of conservative treatment in terms of the ability to return to play and factors influencing return to play in athletes with symptomatic lumbar disc herniation. A total of 100 consecutive athletes (72 male and 28 female who consulted our sports medicine clinic during the 16-year period between September 1993 and October 2009 because of severe low back pain and/or leg pain/numbness due to lumbar disc herniation were studied. The mean age of the subjects was 23 years. All of them were conservatively treated by being advised to discontinue their sporting activities with/without short-term medication. After the subjective symptoms had reduced by more than 80%, individual training was started in order to allow the athletes to return to play. Seventy-nine athletes (79.0% returned to play at an average of 4.8 months (range 1–12 months after the start of treatment and were able to sustain the activities for at least 6 months, the minimum duration of follow-up in the study. The outcome of the conservative treatment was not influenced by the intensity of the sporting activity. Multiple logistic regression analyses showed that the severity of the symptoms prior to the start of treatment was the factor influencing the ability of the athletes to return to play. The present study confirmed the satisfactory short-term outcome of conservative treatment in athletes with symptomatic lumbar disc herniation regarding return to play and revealed that subjective symptoms prior to the start of treatment appeared to be a key factor in return to play after conservative treatment.Keywords: lumbar disc herniation, athletes, return to play, conservative treatment, sciatica, low back pain

  4. Mixed layer processes of the Arabian Sea Warm Pool during spring intermonsoon: a study based on observational and satellite data

    Digital Repository Service at National Institute of Oceanography (India)

    Sabu, P.; Revichandran, C.

    , Durand et al. 2004, Gopalakrishna et al. 2005, Masson et al.2005). However, Kurian and Vinayachandran (2007) suggested the role of orographic effect due to the Western Ghats which reduces the wind speed over the SEAS, resulting in positive heat flux....e., vertical), where the warming is the resultant of the surface heat fluxes and the penetrative radiation. Thus, the previous studies in the SEAS during pre monsoon period suggested that the heat budget of the upper ocean is mainly a balance between...

  5. Glycaemic Control and Associated Self-Management Behaviours in Diabetic Outpatients: A Hospital Based Observation Study in Lusaka, Zambia

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    Emmanuel Mwila Musenge

    2016-01-01

    Full Text Available Background. The control of diabetes mellitus depends on several factors that also include individual lifestyles. We assessed glycaemic control status and self-management behaviours that may influence glycaemic control among diabetic outpatients. Methods. This cross-sectional study among 198 consenting randomly selected patients was conducted at the University Teaching Hospital diabetic clinic between September and December 2013 in Lusaka, Zambia. A structured interview schedule was used to collect data on demographic characteristics, self-management behaviours, and laboratory measurements. Binary logistic regression analysis using IBM SPSS for Windows version 20.0 was carried out to predict behaviours that were associated with glycaemic control status. Results. The proportion of patients that had good glycaemic control status (HbA1c≤ 48 mmol/mol was 38.7% compared to 61.3% that had poor glycaemic control status (HbA1c≥ 49 mmol/mol. Adherence to antidiabetic treatment and fasting plasma glucose predicted glycaemic control status of the patients. However, self-blood glucose monitoring, self-blood glucose monitoring means and exercise did not predict glycaemic control status of the patients.  Conclusion. We find evidence of poor glycaemic control status among most diabetic patients suggesting that health promotion messages need to take into account both individual and community factors to promote behaviours likely to reduce nonadherence.

  6. Secondary malignancies in chronic myeloid leukemia patients after imatinib-based treatment: long-term observation in CML Study IV.

    Science.gov (United States)

    Miranda, M B; Lauseker, M; Kraus, M-P; Proetel, U; Hanfstein, B; Fabarius, A; Baerlocher, G M; Heim, D; Hossfeld, D K; Kolb, H-J; Krause, S W; Nerl, C; Brümmendorf, T H; Verbeek, W; Fauser, A A; Prümmer, O; Neben, K; Hess, U; Mahlberg, R; Plöger, C; Flasshove, M; Rendenbach, B; Hofmann, W-K; Müller, M C; Pfirrmann, M; Hochhaus, A; Hasford, J; Hehlmann, R; Saußele, S

    2016-06-01

    Treatment of chronic myeloid leukemia (CML) has been profoundly improved by the introduction of tyrosine kinase inhibitors (TKIs). Long-term survival with imatinib is excellent with a 8-year survival rate of ∼88%. Long-term toxicity of TKI treatment, especially carcinogenicity, has become a concern. We analyzed data of the CML study IV for the development of secondary malignancies. In total, 67 secondary malignancies were found in 64 of 1525 CML patients in chronic phase treated with TKI (n=61) and interferon-α only (n=3). The most common malignancies (n⩾4) were prostate, colorectal and lung cancer, non-Hodgkin's lymphoma (NHL), malignant melanoma, non-melanoma skin tumors and breast cancer. The standardized incidence ratio (SIR) for all malignancies excluding non-melanoma skin tumors was 0.88 (95% confidence interval (0.63-1.20)) for men and 1.06 (95% CI 0.69-1.55) for women. SIRs were between 0.49 (95% CI 0.13-1.34) for colorectal cancer in men and 4.29 (95% CI 1.09-11.66) for NHL in women. The SIR for NHL was significantly increased for men and women. An increase in the incidence of secondary malignancies could not be ascertained. The increased SIR for NHL has to be considered and long-term follow-up of CML patients is warranted, as the rate of secondary malignancies may increase over time. PMID:26859076

  7. Primary nocturnal enuresis as a risk factor for sleep disorders: an observational questionnaire-based multicenter study

    Directory of Open Access Journals (Sweden)

    Esposito M

    2013-03-01

    Full Text Available Maria Esposito,1 Beatrice Gallai,2 Lucia Parisi,3 Michele Roccella,3 Rosa Marotta,4 Serena Marianna Lavano,4 Giovanni Mazzotta,5 Marco Carotenuto11Center for Childhood Headache, Clinic of Child and Adolescent Neuropsychiatry, Department of Mental Health, Physical and Preventive Medicine, Second University of Naples, Naples, Italy; 2Unit of Child and Adolescent Neuropsychiatry, University of Perugia, Perugia, Italy; 3Child Neuropsychiatry, Department of Psychology, University of Palermo, Palermo, Italy; 4Department of Psychiatry, “Magna Graecia” University of Catanzaro, Catanzaro, Italy; 5Unit of Child and Adolescent Neuropsychiatry, AUSL Umbria 2, Terni, ItalyIntroduction: Primary nocturnal enuresis (PNE is a common problem in developmental age with an estimated overall prevalence ranging from 1.6% to 15%, and possible persistence during adolescence. There is a growing interest in the sleep habits of children affected by PNE, which is derived from the contradictory data present in clinical literature. The aim of the present study was to evaluate the presence of sleep disturbances in a population of children affected by PNE, and to identify whether PNE could be considered as a risk factor for sleep disturbances among children.Materials and methods: A total of 190 PNE children (97 males, 93 females aged 7–15 years, (mean 9.64 ± 1.35 years, and 766 typically developing children matched for age (P = 0.131 and gender (P = 0.963 were enrolled. To evaluate the presence of sleep habits and disturbances, all of the subjects’ mothers filled out the Sleep Disturbances Scale for Children (SDSC, a questionnaire consisting of six subscales: Disorders in Initiating and Maintaining Sleep (DIMS, Sleep Breathing Disorders (SBD, Disorders of Arousal (DA, Sleep–Wake Transition Disorders (SWTD, Disorders of Excessive Somnolence (DOES, and Nocturnal Hyperhidrosis (SHY. The results were divided into “pathological” and “normal” scores using a cut

  8. HARPS Observes the Earth Transiting the Sun — A Method to Study Exoplanet Atmospheres Using Precision Spectroscopy on Large Ground-based Telescopes

    Science.gov (United States)

    Yan, F.; Fosbury, R.; Petr-Gotzens, M.; Pallé, E.; Zhao, G.

    2015-09-01

    Exoplanetary transits offer the opportunity to measure the transmission of long, tangential pathlengths through their atmospheres. Since the fraction of the observed stellar light taking these paths is very small, transit photometric and spectrophotometric measurements of light curves require very high levels of measurement stability, favouring the use of intrinsically stable space telescopes. By studying the Rossiter-McLaughlin effect on the radial velocity of the transited star, pure, high-precision radial velocity measurements can be used to estimate the changes in planetary atmospheric transmission with wavelength: a promising method for future studies of small planets with very large ground-based telescopes since it removes the requirement for extreme photometric stability. This article describes a successful feasibility experiment using the HARPS instrument to measure reflected moonlight during the penumbral phases of a Lunar eclipse, effectively providing an observation of an Earth transit.

  9. Bidirectional Assessment of Stress, job satisfaction and work ability of Educators in day care centres: a real-time observation study - the study protocol (BASE)

    OpenAIRE

    Kusma Bianca; Nienhaus Albert; Spallek Michael; Quarcoo David; Groneberg David A; Mache Stefanie

    2010-01-01

    Abstract Background Occupational demands of educators are not very well researched. Nevertheless their work is subject to several requirements. Whether these demands have an effect on the work ability and the health status of employees has also not been examined. Furthermore it is unclear if the ownership type of day care centres have an influence on job satisfaction and work ability of the pedagogical staff and what kind of resources do exist. Previous studies were mainly based on questionna...

  10. The safety and efficacy of EGF-based cream for the prevention of radiotherapy-induced skin injury: results from a multicenter observational study

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Hyun Cheol [Dept.of Radiation Oncology, Seoul National University College of Medicine, Seoul (Korea, Republic of); Ahn, Seung Do [Dept.of Radiation Oncology, Asan Medical Center, Seoul (Korea, Republic of); Choi, Doo Ho [Dept.of Radiation Oncology, Samsung Medical Center, Seoul (Korea, Republic of); Kang, Min Kyu [Dept.of Radiation Oncology, eungnam University College of Medicine, Daegu (Korea, Republic of); Wu, Hong Gyun [Dept.of Radiation Oncology, Chonnam National University Hwasun Hospital, Huasun (Korea, Republic of)

    2014-09-15

    This study was designed to evaluate the efficacy and safety of topically applied recombinant human epidermal growth factor (rhEGF) for the prevention of radiation-induced dermatitis in cancer patients. From December 2010 to April 2012, a total of 1,172 cancer patients who received radiotherapy (RT) of more than 50 Gy were prospectively enrolled and treated with EGF-based cream. An acute skin reaction classified according to the Radiation Therapy Oncology Group 6-point rating scale was the primary end point and we also assessed the occurrence of edema, dry skin, or pruritus. The percentage of radiation dermatitis with maximum grade 0 and grade 1 was 19% and 58% at the time of 50 Gy, and it became 29% and 47% after completion of planned RT. This increment was observed only in breast cancer patients (from 18%/62% to 32%/49%). Adverse events related to the EGF-based cream developed in 49 patients (4%) with mild erythema the most common. Skin toxicity grade >2 was observed in 5% of the patients. Edema, dry skin, and pruritus grade > or =3 developed in 9%, 9%, and 1% of the patients, respectively. Prophylactic use of an EGF-based cream is effective in preventing radiation dermatitis with tolerable toxicity. Further studies comparing EGF cream with other topical agents may be necessary.

  11. The safety and efficacy of EGF-based cream for the prevention of radiotherapy-induced skin injury: results from a multicenter observational study

    International Nuclear Information System (INIS)

    This study was designed to evaluate the efficacy and safety of topically applied recombinant human epidermal growth factor (rhEGF) for the prevention of radiation-induced dermatitis in cancer patients. From December 2010 to April 2012, a total of 1,172 cancer patients who received radiotherapy (RT) of more than 50 Gy were prospectively enrolled and treated with EGF-based cream. An acute skin reaction classified according to the Radiation Therapy Oncology Group 6-point rating scale was the primary end point and we also assessed the occurrence of edema, dry skin, or pruritus. The percentage of radiation dermatitis with maximum grade 0 and grade 1 was 19% and 58% at the time of 50 Gy, and it became 29% and 47% after completion of planned RT. This increment was observed only in breast cancer patients (from 18%/62% to 32%/49%). Adverse events related to the EGF-based cream developed in 49 patients (4%) with mild erythema the most common. Skin toxicity grade >2 was observed in 5% of the patients. Edema, dry skin, and pruritus grade > or =3 developed in 9%, 9%, and 1% of the patients, respectively. Prophylactic use of an EGF-based cream is effective in preventing radiation dermatitis with tolerable toxicity. Further studies comparing EGF cream with other topical agents may be necessary.

  12. Bidirectional Assessment of Stress, job satisfaction and work ability of Educators in day care centres: a real-time observation study - the study protocol (BASE

    Directory of Open Access Journals (Sweden)

    Kusma Bianca

    2010-06-01

    Full Text Available Abstract Background Occupational demands of educators are not very well researched. Nevertheless their work is subject to several requirements. Whether these demands have an effect on the work ability and the health status of employees has also not been examined. Furthermore it is unclear if the ownership type of day care centres have an influence on job satisfaction and work ability of the pedagogical staff and what kind of resources do exist. Previous studies were mainly based on questionnaire data. Objective data does not exist. Therefore the aim of this investigation is to collect precise data relating to work of educators. Methods Effects of different types of ownership of day care centres on job satisfaction and work ability of educators will be assessed with the help of objective real time studies in combination with multi-level psycho diagnostic measurements. Discussion The present study is the first of its kind. Up to now there are no computer-based real time studies on workflow of pedagogical staff with regard to assess their work-related stress. Following an exhaustive documentation of educators work processes the day-to-day task can be estimated and approaches for prevention can be developed. This can substantially contribute to an overall improvement of child care in Germany.

  13. Ground-based observations of exoplanet atmospheres

    NARCIS (Netherlands)

    Mooij, Ernst Johan Walter de

    2011-01-01

    This thesis focuses on the properties of exoplanet atmospheres. The results for ground-based near-infrared secondary eclipse observations of three different exoplanets, TrES-3b, HAT-P-1b and WASP-33b, are presented which have been obtained with ground-based telescopes as part of the GROUSE project.

  14. Does lumbar spinal degeneration begin with the anterior structures? A study of the observed epidemiology in a community-based population

    Directory of Open Access Journals (Sweden)

    Jarvik Jeffrey G

    2011-09-01

    Full Text Available Abstract Background- Prior studies that have concluded that disk degeneration uniformly precedes facet degeneration have been based on convenience samples of individuals with low back pain. We conducted a study to examine whether the view that spinal degeneration begins with the anterior spinal structures is supported by epidemiologic observations of degeneration in a community-based population. Methods- 361 participants from the Framingham Heart Study were included in this study. The prevalences of anterior vertebral structure degeneration (disk height loss and posterior vertebral structure degeneration (facet joint osteoarthritis were characterized by CT imaging. The cohort was divided into the structural subgroups of participants with 1 no degeneration, 2 isolated anterior degeneration (without posterior degeneration, 3 combined anterior and posterior degeneration, and 4 isolated posterior degeneration (without anterior structure degeneration. We determined the prevalence of each degeneration pattern by age group Results- As the prevalence of the no degeneration and isolated anterior degeneration patterns decreased with increasing age group, the prevalence of the combined anterior/posterior degeneration pattern increased. 22% of individuals demonstrated isolated posterior degeneration, without an increase in prevalence by age group. Isolated posterior degeneration was most common at the L5-S1 and L4-L5 spinal levels. In multivariate analyses, disk height loss was independently associated with facet joint osteoarthritis, as were increased age (years, female sex, and increased BMI (kg/m2, but not smoking. Conclusions- The observed epidemiology of lumbar spinal degeneration in the community-based population is consistent with an ordered progression beginning in the anterior structures, for the majority of individuals. However, some individuals demonstrate atypical patterns of degeneration, beginning in the posterior joints. Increased age and BMI

  15. An observational study of excellence in science teaching based on a sample of outstanding science teachers: Methods of teaching excellence in science

    Science.gov (United States)

    Mazmanian, Victor

    The aim of this study was to document the teaching and learning strategies utilized by a group of science teachers, who were recipients of the Presidential Awards for Excellence in Science and Math Teaching (PAESMT). Six science teachers were observed in their classrooms while they were teaching. Thirty-six lessons were analyzed using a framework of categories of analysis to determine the special traits and common exceptional methods that these teachers had. The findings confirmed the ones predicted by theoretical frameworks of cognitive science and current models of constructivism in teaching. The results of the study supported the importance of the role of the teacher as an active agent in construction of knowledge while also providing sufficient student freedom of exploration and self-realization as needed to grow intellectually and develop skills in metacognition (e.g., reflective critical thought, and learning how to learn). Further, the analyses revealed the complementarity between the teacher's methodology and the processes of student cognition. Some misconceptions that commonly appeared among the observed science students were also documented. The study also explored possible methods to rectify these misconceptions, based in part on prior publications and also on observations of the PAESMT teachers' strategies. The results of this study showed the unique methods of teaching employed by PAESMT recipients to an extent that reached beyond the results of previous research, which published traits and characteristics of such teachers. This study determined the common traits among these teachers and identified their common methods of teaching science. The teacher's role as a facilitator was documented repeatedly among these award-winning teachers and was determined to be an integral tool for the students' successful knowledge construction and development of accurate scientific ways of thinking.

  16. Unknown input observer based chaotic secure communication

    International Nuclear Information System (INIS)

    Based on the idea of unknown input observers (UIOs), this Letter considers the problem of chaos secure communication within the master-slave configuration. The unknown constant disturbance of parameters in chaotic systems and the unknown input in chaotic signals can be regarded as messages to be recovered in the slave end. If certain conditions are satisfied, we can recover all the unknown messages by designing the UIO based slave. Theoretical analysis and simulation results fully verify the effectiveness of the proposed scheme

  17. Task-based evaluation of a 4D MAP-RBI-EM image reconstruction method for gated myocardial perfusion SPECT using a human observer study

    Science.gov (United States)

    Lee, Taek-Soo; Higuchi, Takahiro; Lautamäki, Riikka; Bengel, Frank M.; Tsui, Benjamin M. W.

    2015-09-01

    We evaluated the performance of a new 4D image reconstruction method for improved 4D gated myocardial perfusion (MP) SPECT using a task-based human observer study. We used a realistic 4D NURBS-based Cardiac-Torso (NCAT) phantom that models cardiac beating motion. Half of the population was normal; the other half had a regional hypokinetic wall motion abnormality. Noise-free and noisy projection data with 16 gates/cardiac cycle were generated using an analytical projector that included the effects of attenuation, collimator-detector response, and scatter (ADS), and were reconstructed using the 3D FBP without and 3D OS-EM with ADS corrections followed by different cut-off frequencies of a 4D linear post-filter. A 4D iterative maximum a posteriori rescaled-block (MAP-RBI)-EM image reconstruction method with ADS corrections was also used to reconstruct the projection data using various values of the weighting factor for its prior. The trade-offs between bias and noise were represented by the normalized mean squared error (NMSE) and averaged normalized standard deviation (NSDav), respectively. They were used to select reasonable ranges of the reconstructed images for use in a human observer study. The observers were trained with the simulated cine images and were instructed to rate their confidence on the absence or presence of a motion defect on a continuous scale. We then applied receiver operating characteristic (ROC) analysis and used the area under the ROC curve (AUC) index. The results showed that significant differences in detection performance among the different NMSE-NSDav combinations were found and the optimal trade-off from optimized reconstruction parameters corresponded to a maximum AUC value. The 4D MAP-RBI-EM with ADS correction, which had the best trade-off among the tested reconstruction methods, also had the highest AUC value, resulting in significantly better human observer detection performance when detecting regional myocardial wall motion

  18. Task-based evaluation of a 4D MAP-RBI-EM image reconstruction method for gated myocardial perfusion SPECT using a human observer study

    International Nuclear Information System (INIS)

    We evaluated the performance of a new 4D image reconstruction method for improved 4D gated myocardial perfusion (MP) SPECT using a task-based human observer study. We used a realistic 4D NURBS-based Cardiac-Torso (NCAT) phantom that models cardiac beating motion. Half of the population was normal; the other half had a regional hypokinetic wall motion abnormality. Noise-free and noisy projection data with 16 gates/cardiac cycle were generated using an analytical projector that included the effects of attenuation, collimator-detector response, and scatter (ADS), and were reconstructed using the 3D FBP without and 3D OS-EM with ADS corrections followed by different cut-off frequencies of a 4D linear post-filter. A 4D iterative maximum a posteriori rescaled-block (MAP-RBI)-EM image reconstruction method with ADS corrections was also used to reconstruct the projection data using various values of the weighting factor for its prior. The trade-offs between bias and noise were represented by the normalized mean squared error (NMSE) and averaged normalized standard deviation (NSDav), respectively. They were used to select reasonable ranges of the reconstructed images for use in a human observer study. The observers were trained with the simulated cine images and were instructed to rate their confidence on the absence or presence of a motion defect on a continuous scale. We then applied receiver operating characteristic (ROC) analysis and used the area under the ROC curve (AUC) index. The results showed that significant differences in detection performance among the different NMSE-NSDav combinations were found and the optimal trade-off from optimized reconstruction parameters corresponded to a maximum AUC value. The 4D MAP-RBI-EM with ADS correction, which had the best trade-off among the tested reconstruction methods, also had the highest AUC value, resulting in significantly better human observer detection performance when detecting regional myocardial wall motion

  19. Earth Observation-Based Dwelling Detection Approaches in a Highly Complex Refugee Camp Environment — A Comparative Study

    Directory of Open Access Journals (Sweden)

    Kristin Spröhnle

    2014-09-01

    Full Text Available For effective management of refugee camps or camps for internally displaced persons (IDPs relief organizations need up-to-date information on the camp situation. In cases where detailed field assessments are not available, Earth observation (EO data can provide important information to get a better overview about the general situation on the ground. In this study, different approaches for dwelling detection were tested using the example of a highly complex camp site in Somalia. On the basis of GeoEye-1 imagery, semi-automatic object-based and manual image analysis approaches were applied, compared and evaluated regarding their analysis results (absolute numbers, population estimation, spatial pattern, statistical correlations and production time. Although even the results of the visual image interpretation vary considerably between the interpreters, there is a similar pattern resulting from all methods, which shows same tendencies for dense and sparse populated areas. The statistical analyses revealed that all approaches have problems in the more complex areas, whereas there is a higher variance in manual interpretations with increasing complexity. The application of advanced rule sets in an object-based environment allowed a more consistent feature extraction in the area under investigation that can be obtained at a fraction of the time compared to visual image interpretation if large areas have to be observed.

  20. UFOs: Observations, Studies and Extrapolations

    CERN Document Server

    Baer, T; Barnes, M J; Bartmann, W; Bracco, C; Carlier, E; Cerutti, F; Dehning, B; Ducimetière, L; Ferrari, A; Ferro-Luzzi, M; Garrel, N; Gerardin, A; Goddard, B; Holzer, E B; Jackson, S; Jimenez, J M; Kain, V; Zimmermann, F; Lechner, A; Mertens, V; Misiowiec, M; Nebot Del Busto, E; Morón Ballester, R; Norderhaug Drosdal, L; Nordt, A; Papotti, G; Redaelli, S; Uythoven, J; Velghe, B; Vlachoudis, V; Wenninger, J; Zamantzas, C; Zerlauth, M; Fuster Martinez, N

    2012-01-01

    UFOs (“ Unidentified Falling Objects”) could be one of the major performance limitations for nominal LHC operation. Therefore, in 2011, the diagnostics for UFO events were significantly improved, dedicated experiments and measurements in the LHC and in the laboratory were made and complemented by FLUKA simulations and theoretical studies. The state of knowledge is summarized and extrapolations for LHC operation in 2012 and beyond are presented. Mitigation strategies are proposed and related tests and measures for 2012 are specified.

  1. Analysis of observed and model mt fields based on three-dimensional mathematical modeling: Case study of the Verkhnee Penzhino-Korf profile

    Science.gov (United States)

    Belyavskii, V. V.; Nikolayev, Yu. I.

    2011-01-01

    We propose a system for the analysis of magnetotelluric (MT) data, which makes use of the invariant characteristics of the impedance tensor such as the maximum and minimum induction curves and the phase tensor. We examine the coefficients of the appearance and normalization of principal values of the impedance tensor. By the case study for Koryakiya, it is shown that the three-dimensional (3D) mathematical modeling and the Wiese-Parkinson vectors allow one to correct the results of one-dimensional (1D) and two-dimensional (2D) inversion of MT curves. Comparison between model and observed data based on the 1D inversion of MTS curves provides a pictorial view of the distortions of MT curves and their sensitivity to the parameters of a geological cross section.

  2. Arithmetic, mutually unbiased bases and complementary observables

    International Nuclear Information System (INIS)

    Complementary observables in quantum mechanics may be viewed as Frobenius structures in a dagger monoidal category, such as the category of finite dimensional Hilbert spaces over the complex numbers. On the other hand, their properties crucially depend on the discrete Fourier transform and its associated quantum torus, requiring only the finite fields that underlie mutually unbiased bases. In axiomatic topos theory, the complex numbers are difficult to describe and should not be invoked unnecessarily. This paper surveys some fundamentals of quantum arithmetic using finite field complementary observables, with a view considering more general axiom systems.

  3. Neural network-based estimates of Southern Ocean net community production from in-situ O2 / Ar and satellite observation: a methodological study

    Directory of Open Access Journals (Sweden)

    C.-H. Chang

    2013-10-01

    Full Text Available Southern Ocean organic carbon export plays an important role in the global carbon cycle, yet its basin-scale climatology and variability are uncertain due to limited coverage of in situ observations. In this study, a neural network approach based on the self-organizing map (SOM is adopted to construct weekly gridded (1° × 1° maps of organic carbon export for the Southern Ocean from 1998 to 2009. The SOM is trained with in situ measurements of O2 / Ar-derived net community production (NCP that are tightly linked to the carbon export in the mixed layer on timescales of 1–2 weeks, and six potential NCP predictors: photosynthetically available radiation (PAR, particulate organic carbon (POC, chlorophyll (Chl, sea surface temperature (SST, sea surface height (SSH, and mixed layer depth (MLD. This non-parametric approach is based entirely on the observed statistical relationships between NCP and the predictors, and therefore is strongly constrained by observations. A thorough cross-validation yields three retained NCP predictors, Chl, PAR, and MLD. Our constructed NCP is further validated by good agreement with previously published independent in situ derived NCP of weekly or longer temporal resolution through real-time and climatological comparisons at various sampling sites. The resulting November–March NCP climatology reveals a pronounced zonal band of high NCP roughly following the subtropical front in the Atlantic, Indian and western Pacific sectors, and turns southeastward shortly after the dateline. Other regions of elevated NCP include the upwelling zones off Chile and Namibia, Patagonian Shelf, Antarctic coast, and areas surrounding the Islands of Kerguelen, South Georgia, and Crozet. This basin-scale NCP climatology closely resembles that of the satellite POC field and observed air-sea CO2 flux. The long-term mean area-integrated NCP south of 50° S from our dataset, 14 mmol C m–2 d–1, falls within the range of 8.3–24 mmol C m

  4. Diagnostic Support for Selected Paediatric Pulmonary Diseases Using Answer-Pattern Recognition in Questionnaires Based on Combined Data Mining Applications--A Monocentric Observational Pilot Study.

    Directory of Open Access Journals (Sweden)

    Ann-Katrin Rother

    Full Text Available Clinical symptoms in children with pulmonary diseases are frequently non-specific. Rare diseases such as primary ciliary dyskinesia (PCD, cystic fibrosis (CF or protracted bacterial bronchitis (PBB can be easily missed at the general practitioner (GP.To develop and test a questionnaire-based and data mining-supported tool providing diagnostic support for selected pulmonary diseases.First, interviews with parents of affected children were conducted and analysed. These parental observations during the pre-diagnostic time formed the basis for a new questionnaire addressing the parents' view on the disease. Secondly, parents with a sick child (e.g. PCD, PBB answered the questionnaire and a data base was set up. Finally, a computer program consisting of eight different classifiers (support vector machine (SVM, artificial neural network (ANN, fuzzy rule-based, random forest, logistic regression, linear discriminant analysis, naive Bayes and nearest neighbour and an ensemble classifier was developed and trained to categorise any given new questionnaire and suggest a diagnosis. For estimating the diagnostic accuracy, we applied ten-fold stratified cross validation.All questionnaires of patients suffering from CF, asthma (AS, PCD, acute bronchitis (AB and the healthy control group were correctly diagnosed by the fusion algorithm. For the pneumonia (PM group 19/21 (90.5% and for the PBB group 17/18 (94.4% correct diagnoses could be reached. The program detected the correct diagnoses with an overall sensitivity of 98.8%. Receiver operating characteristics (ROC analyses confirmed the accuracy of this diagnostic tool. Case studies highlighted the applicability of the tool in the daily work of a GP.For children with symptoms of pulmonary diseases a questionnaire-based diagnostic support tool using data mining techniques exhibited good results in arriving at diagnostic suggestions. In the hands of a doctor, this tool could be of value in arousing awareness for

  5. In-vehicle and site-based observations of vehicles and cyclists : a small-scale ND study in The Netherlands. PROmoting real Life Observations for Gaining Understanding of road user behaviour in Europe PROLOGUE, Deliverable D3.4

    NARCIS (Netherlands)

    Christoph, M. Nes, N. van Pauwelussen, J. Mansvelders, R. Horst, A.R.A. van der & Hoedemaeker, M.

    2011-01-01

    The main objective of the project PROLOGUE (PROmoting real Life Observations for Gaining Understanding of road user behaviour in Europe) is to explore the feasibility and usefulness of a large-scale European naturalistic driving observation study. The work described in this deliverable focused on th

  6. Transport pathways of CO in the African upper troposphere during the monsoon season: a study based upon the assimilation of spaceborne observations

    OpenAIRE

    Barret, B.; Ricaud, P.; Mari, C.; Attié, J.-L.; Bousserez, N.; Josse, B.; Flochmoën, E.; N. J. Livesey; Massart, S.; Peuch, V.-H.; Piacentini, A.; Sauvage, B.; V. Thouret; Cammas, J.-P.

    2008-01-01

    The transport pathways of carbon monoxide (CO) in the African Upper Troposphere (UT) during the West African Monsoon (WAM) is investigated through the assimilation of CO observations by the Aura Microwave Limb Sounder (MLS) in the MOCAGE Chemistry Transport Model (CTM). The assimilation setup, based on a 3-D First Guess at Assimilation Time (3-D-FGAT) variational method is described. Comparisons between the assimilated CO fields and in situ airborne observations from the MOZAIC program betwee...

  7. In-vehicle and site-based observations of vehicles and cyclists. A small-scale ND study in the Netherlands. PROLOGUE Deliverable D3.4

    NARCIS (Netherlands)

    Christoph, M.; Nes, N. van; Pauwelussen, J.J.A.; Mansvelders, R.; Horst, A.R.A. van der; Hoedemaeker, D.M.

    2010-01-01

    The main objective of the project PROLOGUE (PROmoting real Life Observations for Gaining Understanding of road user behaviour in Europe) is to explore the feasibility and usefulness of a large-scale European naturalistic driving observation study. The work described in this deliverable focused on th

  8. Effectiveness and cost-effectiveness of the Salut Programme: a universal health promotion intervention for parents and children—protocol of a register-based retrospective observational study

    Science.gov (United States)

    Feldman, Inna; Eurenius, Eva; Häggström, Jenny; Sampaio, Filipa; Lindkvist, Marie; Pulkki-Brännström, Anni-Maria; Ivarsson, Anneli

    2016-01-01

    Introduction There is inadequate evidence for the effectiveness and cost-effectiveness of health promotion interventions. The Salut Programme aims to reach all parents and children in the Västerbotten County of Sweden with a combination of health promotion interventions initiated during pregnancy and continued over the childhood period. This study protocol describes an effectiveness study and an economic evaluation study, where the ongoing Salut Programme is compared to care-as-usual over the periods of pregnancy, delivery and the child's first 2 years of life. Methods A register-based retrospective observational study design will be used with existing data sources with respect to exposures and outcomes. Outcomes of interest are clustered at 3 points: around the child's birth, 1 month after the child's birth and 2 years after the child's birth. We will simulate an experiment by retrospectively identifying and comparing children and their parents in the geographical areas where the Salut Programme was implemented since 2006 and onwards, and the areas where the Programme was not implemented before 2009. Outcomes will be analysed and compared for the premeasure period, and the postmeasure period for both groups. Our analysis combines difference-in-difference estimation with matching. A complementary analysis will be carried out on the longitudinal subsample of mothers who gave birth at least once during each of the time periods. The economic evaluation aims to capture the wider societal costs and benefits of the Salut Programme for the first 2 years of the children's lives. Incremental costs will be compared with incremental health gains and the results will be presented as a cost-consequence analysis. Ethics and dissemination The Regional Ethical Review Board in Umeå has given clearance for the Salut Programme research (2010-63-31M). No individual's identity will be revealed when presenting results. This study will provide information that can guide

  9. Hospital Based Prospective Observational Study to Audit the Prescription Practices and Outcomes of Paediatric Patients (6 months to 5 years age group) Presenting with Acute Diarrhea

    Science.gov (United States)

    Kondekar, Santosh; Rathi, Surbhi

    2016-01-01

    Introduction Diarrhea is a leading killer of children, accounting for 9% of all deaths among under-five children worldwide. WHO protocol deviation in management of diarrheas in children is likely due to various reasons. Aim To study the prescription practices, regarding adherence to WHO protocol and deviations, in the management of acute diarrhea in children presenting at a tertiary care hospital and its impact on the outcome. Materials and Methods This was a prospective observational hospital based study at a tertiary care carried out over a 12-month period including all cases of acute diarrhea (defined as 3 or more loose stools in last 24 hours) in children belonging to the age group of 6 months to 5 years. Patients were followed up on day 3,7,14 and 28 from the day of presentation. Software SPSS Version 17.0 was used for analysis. Correlation regression analysis was used to study predictiveness of different variables affecting outcome. Results In this study, 447 children aged between 6 months and 5 years were enrolled, of which 45 cases were lost in follow-up and excluded. The median age was 14 months. Some deviation from WHO protocol was noted in 78.4% of the cases. Most common deviations from WHO protocol were addition of probiotics (78.1% of cases) and addition of race cadotril (15.9% of cases). Inadvertent use of antibiotics in diarrhea was noted in 12.2% of cases. Presence of fever was strong predictor for use of antibiotics. Cases of early recovery within 3 days of presentation were higher in WHO protocol deviation group. Use of probiotics had statistically significant association with early recovery. Conclusion In diarrhea management, WHO protocol deviation is common. Probiotics are likely to help in early recovery. PMID:27437317

  10. Space Based Radar To Observe Space Debris

    OpenAIRE

    Tolkachev, A.A.; Zolotarev, M.M.; Loukiaschenko, V.I.; Raikunov, G.G.; Yaremenko, A.I.

    1998-01-01

    Space debris of 1÷3mm size is known to be hazardous for astronauts and space vehicles. At the same time the possibility to notice such objects by ground based optical and radar devices in the nearest future is rather problematic. Here we propose an idea of space radar for observation of cicumterrestrial space debris. The radar works in short wave part of millimetre band, which is mostly suitable for this purpose. The radar provides detecting and tracking of 1mm size objects within 40000m2 are...

  11. VLF/LF signal studies of the ionospheric response to strong seismic activity in the Far Eastern region combining the DEMETER and ground-based observations

    Science.gov (United States)

    Rozhnoi, A.; Solovieva, M.; Parrot, M.; Hayakawa, M.; Biagi, P.-F.; Schwingenschuh, K.; Fedun, V.

    The paper presents the results of a joint analysis of ground-based and satellite observations of very low-frequency and low-frequency (VLF/LF) signals during periods of strong seismic activity in the region of Kuril Islands and Japan in 2004-2010. Ground and satellite data was processed using a method based on the difference between the real signal in nighttime and that of a model. The results of the analysis show a good correlation between ground-based and satellite data for several cases of strong (M ⩾ 6.8) earthquakes.

  12. Burden and outcomes of pressure ulcers in cancer patients receiving the Kerala model of home based palliative care in India: Results from a prospective observational study

    Directory of Open Access Journals (Sweden)

    Biji M Sankaran

    2015-01-01

    Full Text Available Aim: To report the prevalence and outcomes of pressure ulcers (PU seen in a cohort of cancer patients requiring home-based palliative care. Materials and Methods: All patients referred for home care were eligible for this prospective observational study, provided they were living within a distance of 35 km from the institute and gave informed consent. During each visit, caregivers were trained and educated for providing nursing care for the patient. Dressing material for PU care was provided to all patients free of cost and care methods were demonstrated. Factors influencing the occurrence and healing of PUs were analyzed using logistic regression. Duration for healing of PU was calculated using the Kaplan Meier method. P < 0.05 are taken as significant. Results: Twenty-one of 108 (19.4% enrolled patients had PU at the start of homecare services. None of the patients developed new PU during the course of home care. Complete healing of PU was seen in 9 (42.9% patients. The median duration for healing of PU was found to be 56 days. Median expenditure incurred in patients with PU was Rs. 2323.40 with a median daily expenditure of Rs. 77.56. Conclusions: The present model of homecare service delivery was found to be effective in the prevention and management of PUs. The high prevalence of PU in this cohort indicates a need for greater awareness for this complication. Clinical Trial Registry Number: CTRI/2014/03/004477

  13. The effect of third-party reporting on adoption of evidence-based mesalazine regimens in ulcerative colitis: an observational study

    NARCIS (Netherlands)

    Kruis, W.; Leifeld, L.; Morgenstern, J.; Pfutzer, R.; Reimers, B.; Ceplis-Kastner, S.; Auchter, K.H.; Han, H.; Metz, K.; Gutberlet, H.; Beuthner, D.; Gerhard, B.; Lampe, D.; Look, M.; Scholze, K.; Striemer, R.; Gynz-Rekowski, M.E. von; Wengler, K.; Walff, R.; Schmidt-Heinevetter, G.; Gille, K.; Nordhoff, S.; Schulte-Witte, H.; Behrendt, J.; Hahn, A.; Al-Shamaa, A.; Widjaja, A.; Göbel, U.; Landry, W.; Leib, H.H.; Epping-Stippel, L.; Niedermeyer, H.; Pakravan, F.; Krüger, P.; Shoilewa, A.; Schwarzhoff, R.; Grubitzsch, M.; Weisflog, M.; Koßler-Wiesweg, C.; Röcken, A.; Hermans, M.L.; Jaehn, T.; Kihn, R.; Stern, M.; Fink, R.; Geyer, P.; Herold, C.; Meyer-Hilse, F.; Olejnik, H.; Samel, S.T.; Treml, O.; Bamberger, A.; Bruhn, J.; Holch, P.; Keck, B.; Arnauld, P. von; Aldinger, I.; Schmidt, J.T.; Schwarz, H.; Schmidt, K.; Syamken, S.; Bierbaum, C.; Schulz, J.; Jessen, K.; Stegen, G.; Hohn, H.; Weber, C.; Schwerdtfeger, M.; Theuerkauf, B.; Stölzle, B.; Botzler, R.; Dietz, A.; Sellinger, M.; Uebel, P.; Fiedler, J.; Schink, U.; Will, E.; Gratz, T.; Küppers, F.; Asdonk, D.; Kellner, H.; Konrad, T.; Erren, P.; Horn, J.; Klein, U.; Hebel, M.; Hoesl, M.; Pfäffl, S.; Bartner, J.; Donabauer, B.; Schöniger, F.; Brandt, W.; Grümmer, H.; Klaus, M.; Wiechmann, H.; Schönfeld, G.; Knigge, K.P.; Sehland, D.; Strotmann, H.J.; Frank, B.; Wankmüller, C.; Frey, H.; Kienle, U.; Linde, A.; Hommel, E.; Teubner, K.; Wust, C.; Dewitz, G. von; Andersen, M.; Hackelsberger, A.; Hammann, V.

    2013-01-01

    BACKGROUND AND AIMS: The optimal mesalazine dosing strategy for ulcerative colitis (UC) continues to evolve. The current study aimed to explore whether documenting drug use could prompt changes in prescribing habits. METHODS: In a multicenter, prospective, observational study, outpatients with activ

  14. Transport pathways of CO in the African upper troposphere during the monsoon season: a study based upon the assimilation of spaceborne observations

    Directory of Open Access Journals (Sweden)

    B. Barret

    2008-02-01

    Full Text Available The transport pathways of carbon monoxide (CO in the African Upper Troposphere (UT during the West African Monsoon (WAM is investigated through the assimilation of CO observations by the Aura Microwave Limb Sounder (MLS in the MOCAGE Chemistry Transport Model (CTM. The assimilation setup, based on a 3-D First Guess at Assimilation Time (3-D-FGAT variational method is described. Comparisons between the assimilated CO fields and in situ airborne observations from the MOZAIC program between Europe and both Southern Africa and Southeast Asia show an overall good agreement around the lowermost pressure level sampled by MLS (~215 hPa. The 4-D assimilated fields averaged over the month of July 2006 have been used to determine the main dynamical processes responsible for the transport of CO in the African UT. The studied period corresponds to the second AMMA (African Monsoon Multidisciplinary Analyses aircraft campaign. At 220 hPa, the CO distribution is characterized by a latitudinal maximum around 5° N mostly driven by convective uplift of air masses impacted by biomass burning from Southern Africa, uplifted within the WAM region and vented predominantly southward by the upper branch of the winter hemisphere Hadley cell. Above 150 hPa, the African CO distribution is characterized by a broad maximum over northern Africa. This maximum is mostly controlled by the large scale UT circulation driven by the Asian Summer Monsoon (ASM and characterized by the Asian Monsoon Anticyclone (AMA centered at 30° N and the Tropical Easterly Jet (TEJ on the southern flank of the anticyclone. Asian pollution uplifted to the UT over large region of Southeast Asia is trapped within the AMA and transported by the anticyclonic circulation over Northeast Africa. South of the AMA, the TEJ is responsible for the tranport of CO-enriched air masses from India and Southeast Asia over Africa. Using the high time resolution provided by the 4-D assimilated fields, we give evidence

  15. Transport pathways of CO in the African upper troposphere during the monsoon season: a study based upon the assimilation of spaceborne observations

    Directory of Open Access Journals (Sweden)

    B. Barret

    2008-06-01

    Full Text Available The transport pathways of carbon monoxide (CO in the African Upper Troposphere (UT during the West African Monsoon (WAM is investigated through the assimilation of CO observations by the Aura Microwave Limb Sounder (MLS in the MOCAGE Chemistry Transport Model (CTM. The assimilation setup, based on a 3-D First Guess at Assimilation Time (3-D-FGAT variational method is described. Comparisons between the assimilated CO fields and in situ airborne observations from the MOZAIC program between Europe and both Southern Africa and Southeast Asia show an overall good agreement around the lowermost pressure level sampled by MLS (~215 hPa. The 4-D assimilated fields averaged over the month of July 2006 have been used to determine the main dynamical processes responsible for the transport of CO in the African UT. The studied period corresponds to the second AMMA (African Monsoon Multidisciplinary Analyses aircraft campaign. At 220 hPa, the CO distribution is characterized by a latitudinal maximum around 5° N mostly driven by convective uplift of air masses impacted by biomass burning from Southern Africa, uplifted within the WAM region and vented predominantly southward by the upper branch of the winter hemisphere Hadley cell. Above 150 hPa, the African CO distribution is characterized by a broad maximum over northern Africa. This maximum is mostly controlled by the large scale UT circulation driven by the Asian Summer Monsoon (ASM and characterized by the Asian Monsoon Anticyclone (AMA centered at 30° N and the Tropical Easterly Jet (TEJ on the southern flank of the anticyclone. Asian pollution uplifted to the UT over large region of Southeast Asia is trapped within the AMA and transported by the anticyclonic circulation over Northeast Africa. South of the AMA, the TEJ is responsible for the tranport of CO-enriched air masses from India and Southeast Asia over Africa. Using the high time resolution provided by the 4-D assimilated fields, we give evidence

  16. Operational evapotranspiration based on Earth observation satellites

    Science.gov (United States)

    Gellens-Meulenberghs, Françoise; Ghilain, Nicolas; Arboleda, Alirio; Barrios, Jose-Miguel

    2016-04-01

    Geostationary satellites have the potential to follow fast evolving atmospheric and Earth surface phenomena such those related to cloud cover evolution and diurnal cycle. Since about 15 years, EUMETSAT has set up a network named 'Satellite Application Facility' (SAF, http://www.eumetsat.int/website/home/Satellites/GroundSegment/Safs/index.html) to complement its ground segment. The Land Surface Analysis (LSA) SAF (http://landsaf.meteo.pt/) is devoted to the development of operational products derived from the European meteorological satellites. In particular, an evapotranspiration (ET) product has been developed by the Royal Meteorological Institute of Belgium. Instantaneous and daily integrated results are produced in near real time and are freely available respectively since the end of 2009 and 2010. The products cover Europe, Africa and the Eastern part of South America with the spatial resolution of the SEVIRI sensor on-board Meteosat Second Generation (MSG) satellites. The ET product algorithm (Ghilain et al., 2011) is based on a simplified Soil-Vegetation-Atmosphere transfer (SVAT) scheme, forced with MSG derived radiative products (LSA SAF short and longwave surface fluxes, albedo). It has been extensively validated against in-situ validation data, mainly FLUXNET observations, demonstrating its good performances except in some arid or semi-arid areas. Research has then been pursued to develop an improved version for those areas. Solutions have been found in reviewing some of the model parameterizations and in assimilating additional satellite products (mainly vegetation indices and land surface temperature) into the model. The ET products will be complemented with related latent and sensible heat fluxes, to allow the monitoring of land surface energy partitioning. The new algorithm version should be tested in the LSA-SAF operational computer system in 2016 and results should become accessible to beta-users/regular users by the end of 2016/early 2017. In

  17. Feasibility of CBCT-based target and normal structure delineation in prostate cancer radiotherapy: Multi-observer and image multi-modality study

    International Nuclear Information System (INIS)

    Background and purpose: In-room cone-beam CT (CBCT) imaging and adaptive treatment strategies are promising methods to decrease target volumes and to spare organs at risk. The aim of this work was to analyze the inter-observer contouring uncertainties of target volumes and organs at risks (oars) in localized prostate cancer radiotherapy using CBCT images. Furthermore, CBCT contouring was benchmarked against other image modalities (CT, MR) and the influence of subjective image quality perception on inter-observer variability was assessed. Methods and materials: Eight prostate cancer patients were selected. Seven radiation oncologists contoured target volumes and oars on CT, MRI and CBCT. Volumes, coefficient of variation (COV), conformity index (cigen), and coordinates of center-of-mass (COM) were calculated for each patient and image modality. Reliability analysis was performed for the support of the reported findings. Subjective perception of image quality was assessed via a ten-scored visual analog scale (VAS). Results: The median volume for prostate was larger on CT compared to MRI and CBCT images. The inter-observer variation for prostate was larger on CBCT (CIgen = 0.57 ± 0.09, 0.61 reliability) compared to CT (CIgen = 0.72 ± 0.07, 0.83 reliability) and MRI (CIgen = 0.66 ± 0.12, 0.87 reliability). On all image modalities values of the intra-observer reliability coefficient (0.97 for CT, 0.99 for MR and 0.94 for CBCT) indicated high reproducibility of results. For all patients the root mean square (RMS) of the inter-observer standard deviation (σ) of the COM was largest on CBCT with σ(x) = 0.4 mm, σ(y) = 1.1 mm, and σ(z) = 1.7 mm. The concordance in delineating OARs was much stronger than for target volumes, with average CIgen > 0.70 for rectum and CIgen > 0.80 for bladder. Positive correlations between CIgen and VAS score of the image quality were observed for the prostate, seminal vesicles and rectum. Conclusions: Inter-observer variability for target

  18. Linking ground motion measurements and macro-seismic observations in France: A case study based on the RAP (accelerometric) and BCSF (macro-seismic) databases

    International Nuclear Information System (INIS)

    Comparison between accelerometric and macro-seismic observations is made for three mw∼4.5 earthquakes of eastern France between 2003 and 2005. Scalar and spectral instrumental parameters are processed from the accelerometric data recorded by nine accelerometric stations located between 29 km and 180 km from the epicentres. Macro-seismic data are based on the French internet reports. In addition to the individual macro-seismic intensity, analysis of the internal correlation between the encoded answers highlights four predominant fields of questions, bearing different physical meanings: 1) 'vibratory motions of small objects', 2) 'displacement and fall of objects', 3) 'acoustic noise', and 4) 'personal feelings'. Best correlations between macro-seismic and instrumental observations are obtained when the macro-seismic parameters are averaged over 10 km radius circles around each station. macro-seismic intensities predicted by published pgv-intensity relationships quite agree with the observed intensities, contrary to those based on pga. The correlations between the macro-seismic and instrumental data, for intensities between ii and v (ems-98), show that pgv is the instrumental parameter presenting the best correlation with all macro-seismic parameters. The correlation with response spectra, exhibits clear frequency dependence over a limited frequency range [0.5-33 hz]. Horizontal and vertical components are significantly correlated with macro-seismic parameters between 1 and 10 hz, a range corresponding to both natural frequencies of most buildings and high energy content in the seismic ground motion. Between 10 and 25 hz, a clear lack of correlation between macro-seismic and instrumental data is observed, while beyond 25 hz the correlation coefficient increases, approaching that of the PGA correlation level. (author)

  19. STRengthening analytical thinking for observational studies

    DEFF Research Database (Denmark)

    Altman, Douglas G.; le Cessie, Saskia; Abrahamowicz, Michal;

    2014-01-01

    The validity and practical utility of observational medical research depends critically on good study design, excellent data quality, appropriate statistical methods and accurate interpretation of results. Statistical methodology has seen substantial development in recent times. Unfortunately, ma...

  20. Observing Protein & Energy Nutrition (OPEN) Study

    Science.gov (United States)

    The Observing Protein and Energy Nutrition (OPEN) Study was designed to assess dietary measurement error by comparing results from self-reported dietary intake data with four dietary biomarkers: doubly labeled water and urinary nitrogen, sodium, and potassium.

  1. Variation of adverse drug reaction profile of platinum-based chemotherapy with body mass index in patients with solid tumors: An observational study

    Directory of Open Access Journals (Sweden)

    Dattatreyo Chatterjee

    2014-01-01

    Full Text Available Objectives: Toxicity of cancer chemotherapy may be affected by nutritional status of patients which is reflected in the body mass index (BMI. We sought to assess whether the adverse drug reaction (ADR profile of platinum-based chemotherapy varies with BMI status. Materials and Methods: Adult patients of either sex, suffering from a solid tumor (lung, head and neck, ovary, gall bladder, stomach, colon and started on platinum-based chemotherapy as initial treatment were included. BMI at chemotherapy commencement was obtained from medical records. Events were recorded and graded as per Eastern Co-operative Oncology Group Common Toxicity Criteria-patients′ complaints; clinically evident signs and laboratory reports were considered. Frequencies of individual adverse events were compared between low BMI (<18.5 kg/m 2 and satisfactory BMI groups. Similar comparisons were done for events with grades 2 or 3 severities. Results: A total of 50 patients were observed over a 3-month period of whom 17 (34% belonged to the low BMI group. Nausea, vomiting, diarrhea, stomatitis, anemia, alopecia, tinnitus and paresthesia were the commonly observed ADRs. The frequencies of anemia (P = 0.152 and vomiting (P = 0.140 and severity of grades of nausea (P = 0.066, anemia (P = 0.120 and paresthesia (P = 0.128 showed a higher trend in the low BMI group though differences were not statistically significant. The frequencies of tinnitus (P = 0.021 and paresthesia overall (P = 0.036 were significantly higher in the low BMI group. Conclusion: ADR profile of primary platinum-based chemotherapy appears to be partly influenced by BMI. This suggests the importance of maintaining adequate nutrition in patients and the need for greater vigilance in those with low BMI.

  2. [The Strengthening the Reporting of Observational Studies in Epidemiology [STROBE] statement: guidelines for reporting observational studies

    DEFF Research Database (Denmark)

    Elm, E. von; Altman, D.G.; Egger, M.;

    2008-01-01

    Much biomedical research is observational. The reporting of such research is often inadequate, which hampers the assessment of its strengths and weaknesses and of a study's generalisability. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) initiative developed rec...

  3. Arrival angle anomalies of Rayleigh waves observed at a broadband array: a systematic study based on earthquake data, full waveform simulations and noise correlations

    Science.gov (United States)

    Pedersen, H. A.; Boué, P.; Poli, P.; Colombi, A.

    2015-12-01

    Deviation of seismic surface waves from the great-circle between source and receiver is illustrated by the anomalies in the arrival angle, that is the difference between the observed backazimuth of the incident waves and the great-circle. Such arrival angle anomalies have been known for decades, but observations remain scattered. We present a systematic study of arrival angle anomalies of fundamental mode Rayleigh waves (20-100 s period interval) from 289 earthquakes and recorded by a broadband network LAPNET, located in northern Finland. These observations are compared with those of full waveform synthetic seismograms for the same events, calculated in a 3-D Earth and also compared with those of seismograms obtained by ambient noise correlation. The arrival angle anomalies for individual events are complex, and have significant variations with period. On average, the mean absolute deviation decreases from ˜9° at 20 s period to ˜3° at 100 s period. The synthetic seismograms show the same evolution, albeit with somewhat smaller deviations. While the arrival angle anomalies are fairly well simulated at long periods, the deviations at short periods are very poorly modelled, demonstrating the importance of the continuous improvement of global crustal models. At 20-30 s period, both event data and numerical simulations have strong multipathing, and relative amplitude changes between different waves will induced differences in deviations between very closely located events. The source mechanism has only limited influence on the deviations, demonstrating that they are directly linked to propagation effects, including near-field effects in the source area. This observation is confirmed by the comparison with seismic noise correlation records, that is where the surface waves correspond to those emitted by a point source at the surface, as the two types of observations are remarkably similar in the cases where earthquakes are located close to seismic stations. This

  4. Study on team evaluation (3). Reliability and validity of behavior observation based team work evaluation method of power plant operator team

    International Nuclear Information System (INIS)

    This report discusses a method to evaluate team work through behavior observation under the view points of 12 which consist of the Team Work Element Model proposed in the series of this study. The method includes a check list with which users evaluate team work 5 rating scale for each viewpoint. The check lists are developed and applied to several real operator teams of power plants under the corporation with two training centers of thermal and nuclear power plants, respectively. Evaluators evaluate team work with watching the video-taped team behavior responding to abnormal conditions. This paper discusses the reliability from whether repeated evaluations shows the same result and multi-evaluators' results show the same result. This also discusses the validity of this method form whether the results from this method matches the evaluators' intuition. As a result, this method is applicable to evaluate team work through behavior observation. (author)

  5. Assessment of Gauze-Based Negative Pressure Wound Therapy in the Split-Thickness Skin Graft Clinical Pathway—An Observational Study

    OpenAIRE

    Dunn, Raymond M.; Ignotz, Ron; Mole, Trevor; Cockwill, John; Smith, Jennifer M

    2011-01-01

    Objectives: Negative pressure wound therapy (NPWT) is a useful therapy in the preparation of wounds prior to application of a split-thickness skin graft (STSG) both “pregraft” and “postgraft” on top of the STSG. Customarily, a foam-based NPWT has been used, but gauze-based therapy is finding an increasing use. Gauze is easy to apply and forgiving of complicated wound geometries so it can be an ideal material in this indication. The aim of this study was to quantitatively assess the clinical e...

  6. Part III: Comparing observed growth of selected test organisms in food irradiation studies with growth predictions calculated by ComBase softwares

    International Nuclear Information System (INIS)

    As a result of intensive predictive microbiological modelling activities, several computer programs and softwares became available recently for facilitating microbiological risk assessment. Among these tools, the establishment of the ComBase, an international database and its predictive modelling softwares of the Pathogen Modelling Program (PMP) set up by the USDA Eastern Regional Research Center, Wyndmore, PA, and the Food Micromodel/Growth Predictor by the United Kingdom's Institute of Food Research, Norwich, are most important. The authors have used the PMP 6.1 software version of ComBase as a preliminary trial to compare observed growth of selected test organisms in relation to their food irradiation work during recent years within the FAO/IAEA Coordinated Food Irradiation Research Projects (D6.10.23 and D6.20.07) with the predicted growth on the basis of growth models available in ComBase for the same species as those of the authors' test organisms. The results of challenge tests with Listeria monocytogenes inoculum in untreated or irradiated experimental batches of semi-prepared breaded turkey meat steaks (cordon bleu), sliced tomato, sliced watermelon, sliced cantaloupe and sous vide processed mixed vegetables, as well as Staphylococcus aureus inoculum of a pasta product, tortellini, were compared with their respective growth models under relevant environmental conditions. This comparison showed good fits in the case of non-irradiated and high moisture food samples, but growth of radiation survivors lagged behind the predicted values. (author)

  7. [Critical reading of analytical observational studies].

    Science.gov (United States)

    García Villar, C; Marín León, I

    2015-11-01

    Analytical observational studies provide very important information about real-life clinical practice and the natural history of diseases and can suggest causality. Furthermore, they are very common in scientific journals. The aim of this article is to review the main concepts necessary for the critical reading of articles about radiological studies with observational designs. It reviews the characteristics that case-control and cohort studies must have to ensure high quality. It explains a method of critical reading that involves checking the attributes that should be evaluated in each type of article using a structured list of specific questions. It underlines the main characteristics that confer credibility and confidence on the article evaluated. Readers are provided with tools for the critical analysis of the observational studies published in scientific journals. PMID:26123855

  8. How labour intensive is a doctor-based delivery model for antiretroviral treatment (ART? Evidence from an observational study in Siem Reap, Cambodia

    Directory of Open Access Journals (Sweden)

    Janssens Bart

    2007-05-01

    Full Text Available Abstract Background Funding for scaling-up antiretroviral treatment (ART in low-income countries has increased substantially, but the lack of human resources for health (HRH is increasingly being identified as an important constraint for scaling-up ART. Methods In a clinic run by Médecins Sans Frontières in Siem Reap, Cambodia, we documented the use of doctor-time for ART in September 2004 and in August 2005, for different phases in ART (pre-ART, ART initiation, ART follow-up Year 1, & ART follow-up Year 2. Based on these observations and using a variety of assumptions for survival of patients on ART (between 90 and 95% annually and for further reductions in doctor-time per patient (between 0 and 10% annually, we estimated the need for doctors for the period 2004 till 2013 in the Siem Reap clinic, and in a hypothetical district in sub-Saharan Africa. Results In the Siem Reap clinic, we found that from 2004 to 2005 the doctor-time needed per patient was reduced by between 14% and 33%, thanks to a reduction in number of visits per patient and shorter consultation times. In 2004, 2.06 full-time equivalent (FTE doctors were needed for 522 patients on ART, and in 2005 this was slightly reduced to 1.97 FTE doctors for 911 patients on ART. By 2013, Siem Reap clinic will need between 2 and 5 FTE doctors for ART. In a district in sub-Saharan Africa with 200,000 inhabitants and 20% adult HIV prevalence, using a similar doctor-based ART delivery model, between 4 and 11 FTE doctors would be needed to cover 50% of ART needs. Conclusion ART is labour intensive. Important reductions in doctor-time per patient can be realized during scaling-up. The doctor-based ART delivery model analysed seems adequate for Cambodia. However, for many districts in sub-Saharan Africa a doctor-based ART delivery model may be incompatible with their HRH constraints.

  9. Embedding clinical interventions into observational studies.

    Science.gov (United States)

    Newman, Anne B; Avilés-Santa, M Larissa; Anderson, Garnet; Heiss, Gerardo; Howard, Wm James; Krucoff, Mitchell; Kuller, Lewis H; Lewis, Cora E; Robinson, Jennifer G; Taylor, Herman; Treviño, Roberto P; Weintraub, William

    2016-01-01

    Novel approaches to observational studies and clinical trials could improve the cost-effectiveness and speed of translation of research. Hybrid designs that combine elements of clinical trials with observational registries or cohort studies should be considered as part of a long-term strategy to transform clinical trials and epidemiology, adapting to the opportunities of big data and the challenges of constrained budgets. Important considerations include study aims, timing, breadth and depth of the existing infrastructure that can be leveraged, participant burden, likely participation rate and available sample size in the cohort, required sample size for the trial, and investigator expertise. Community engagement and stakeholder (including study participants) support are essential for these efforts to succeed. PMID:26611435

  10. The Geolocation model for lunar-based Earth observation

    Science.gov (United States)

    Ding, Yixing; Liu, Guang; Ren, Yuanzhen; Ye, Hanlin; Guo, Huadong; Lv, Mingyang

    2016-07-01

    In recent years, people are more and more aware of that the earth need to treated as an entirety, and consequently to be observed in a holistic, systematic and multi-scale view. However, the interaction mechanism between the Earth's inner layers and outer layers is still unclear. Therefore, we propose to observe the Earth's inner layers and outer layers instantaneously on the Moon which may be helpful to the studies in climatology, meteorology, seismology, etc. At present, the Moon has been proved to be an irreplaceable platform for Earth's outer layers observation. Meanwhile, some discussions have been made in lunar-based observation of the Earth's inner layers, but the geolocation model of lunar-based observation has not been specified yet. In this paper, we present a geolocation model based on transformation matrix. The model includes six coordinate systems: The telescope coordinate system, the lunar local coordinate system, the lunar-reference coordinate system, the selenocentric inertial coordinate system, the geocentric inertial coordinate system and the geo-reference coordinate system. The parameters, lncluding the position of the Sun, the Earth, the Moon, the libration and the attitude of the Earth, can be acquired from the Ephemeris. By giving an elevation angle and an azimuth angle of the lunar-based telescope, this model links the image pixel to the ground point uniquely.

  11. How Safe Do Teenagers Behave on Facebook? An Observational Study

    OpenAIRE

    Vanderhoven, Ellen; Schellens, Tammy; Valcke, Martin; Raes, Annelies

    2014-01-01

    The substantial use of social network sites by teenagers has raised concerns about privacy and security. Previous research about behavior on social network sites was mostly based on surveys and interviews. Observational research overcomes problems inherent to this research method, for example social desirability. However, existing observational research mostly focuses on public profiles of young adults. Therefore, the current observation-study includes 1050 public and non-public Facebook-prof...

  12. Data base to compare calculations and observations

    International Nuclear Information System (INIS)

    Meteorological and climatological data bases were compared with known tritium release points and diffusion calculations to determine if calculated concentrations could replace measure concentrations at the monitoring stations. Daily tritium concentrations were monitored at 8 stations and 16 possible receptors. Automated data retrieval strategies are listed

  13. Ground based observations to probe the ionospheric and magnetospheric plasmas

    International Nuclear Information System (INIS)

    Interactions between the solar wind plasma and the earth's magnetosphere can result in a series of complicated physical processes. One of the most important among them involves transfer of energy, which is believed to be partially dissipated into the magnetosphere and partially temporarily stored in it. Later this stored energy can explosively be released causing a variety of observable changes in the magnetospheric plasmas and fields and especially in ionsopheric particle populations. Ground-based, or near-ground-based, observations of particles, currents and fields have yielded important information when studying both local and global magnetospheric phenomena. A great variety of instruments and techniques have been developed to carry out measurements from ground of phenomena which are of such an extent, both in time and in space, that in situ satellite observations would only give a spatial and temporal snap-shot of them. An overview is given of some of these ground methods to probe the near-earth environment

  14. Biological behavior and disease pattern of carcinoma gallbladder shown on 64-slice CT scanner: A hospital-based retrospective observational study and our experience

    Directory of Open Access Journals (Sweden)

    AND Dwivedi

    2012-01-01

    Full Text Available Purpose: The aim of this diagnostic observational study was to assess the spread and biological behavior of gallbladder cancer using 64-slice computerized tomography (CT scanner in this particular geographic belt (eastern Uttar Pradesh, western Bihar, and northern Madhya Pradesh provinces of North India. Indians are ethnically and culturally different from their Western counterparts among whom the incidence of this disease is comparatively low. Subjects and Methods: After systemic examination, all patients (87 were subjected to ultrasonographic examination. All cases were histopathologically proven. Confirmed cases were subjected to volumetric CT examination of abdomen and pelvis, plain, post contrast and delayed phase. Results: Majority of the cases were adenocarcinoma. There was female preponderance with majority belonging to fifth and sixth decades. Commonest presentation was diffuse, irregular, enhancing wall thickening in 49.4%. Majority had invasion of liver parenchyma (74.7%. Cholelithiasis was seen in 48.3% cases. Invasion of biliary radicals was high (13.8-18.4%. Eleven cases had invasion of portal vein and tumor thrombus, with hepatic artery invasion in one case. In two cases, both hepatic artery and portal vein invasion was seen. Portal and peripancreatic nodal metastasis was seen in 58.5%. Distant metastasis was reported. Conclusion: Few studies involving the Indian population have attempted to use multi-row detector CT to define the biological behavior of carcinoma gallbladder. The opinion whether the pathology is operable or non-operable can reasonably be given. This large-scale, single-center study gives insight about the epidemiology and biological behavior of carcinoma gallbladder.

  15. A study of the long-term properties of Jovian hot spots from HST and ground-based observations between 1994 and 1998

    Science.gov (United States)

    Arregui, E.; Rojas, J. F.; Sanchez-Lavega, A.; Lecacheux, J.; Colas, F.; Miyazaki, I.; Parker, D.

    2000-10-01

    We have used the HST-WFPC2 archived images of Jupiter in the period 1994-1998 together with a large set of CCD ground based images, to study the zonal distribution, long-term motions, lifetimes, interactions and other properties of the hot spot - plume regions at 7 degrees North. Red and near infrared filters covering the wavelength range 650 - 953 nm have been used since they show the hot spots with a high contrast. We have found that the hot spots have velocities ranging from 95 to 112 m/s and are grouped typically in families of three to six members. We do not found any correlation between their velocity and wavenumber. The long-term survey allowed us to identify mergers and splitting of the hot spots areas. The Spanish team was supported by Gobierno Vasco PI 034/97. The French team was supported by the "Programme National de Planetologie."

  16. Forbush Decrease Prediction Based on the Remote Solar Observations

    CERN Document Server

    Dumbovic, Mateja; Calogovic, Jasa

    2015-01-01

    We employ remote observations of coronal mass ejections (CMEs) and the associated solar flares to forecast the CME-related Forbush decreases, i.e., short-term depressions in the galactic cosmic-ray flux. The relationship between the Forbush effect at the Earth and remote observations of CMEs and associated solar flares is studied via a statistical analysis. Relationships between Forbush decrease magnitude and several CME/flare parameters was found, namely the initial CME speed, apparent width, source position, associated solar-flare class and the effect of successive-CME occurrence. Based on the statistical analysis, remote solar observations are employed for a Forbush-decrease forecast. For that purpose, an empirical probabilistic model is constructed that uses selected remote solar observations of CME and associated solar flare as an input, and gives expected Forbush-decrease magnitude range as an output. The forecast method is evaluated using several verification measures, indicating that as the forecast t...

  17. Photorejuvenation observation based on two photon microscopy

    Science.gov (United States)

    Wu, Shu-lian; Li, Hui; Xiao, Zheng-ying; Xie, Shu-sen

    2008-12-01

    With low risk of complications and little down-time, the non-ablative photo-rejuvenation is playing an increasing role in the therapy of the photo-damaged skin, but the appraisal standard is different. This paper mainly observed the effect of the mouse skin irradiated by intense pulse light source through two photo microscopy in sub-micrometer. The spectrum and morphological imaging between pre- and post-irradiated by Intense Pulse Light (IPL) were obtained from two photon microscopy respectively. The outcome showed that non-ablative IPL irradiated the aging mouse skin got the better effect, and then have gained the changes of spectrum intensity and corresponding photon numbers in a rectangular area, these probable achieve the mechanism of light irradiated skin. The intention of this was offer the theory basis in clinic.

  18. Does present use of cardiovascular medication reflect elevated cardiovascular risk scores estimated ten years ago? A population based longitudinal observational study

    Directory of Open Access Journals (Sweden)

    Straand Jørund

    2011-03-01

    Full Text Available Abstract Background It is desirable that those at highest risk of cardiovascular disease should have priority for preventive measures, eg. treatment with prescription drugs to modify their risk. We wanted to investigate to what extent present use of cardiovascular medication (CVM correlates with cardiovascular risk estimated by three different risk scores (Framingham, SCORE and NORRISK ten years ago. Methods Prospective logitudinal observational study of 20 252 participants in The Hordaland Health Study born 1950-57, not using CVM in 1997-99. Prescription data obtained from The Norwegian Prescription Database in 2008. Results 26% of men and 22% of women aged 51-58 years had started to use some CVM during the previous decade. As a group, persons using CVM scored significantly higher on the risk algorithms Framingham, SCORE and NORRISK compared to those not treated. 16-20% of men and 20-22% of women with risk scores below the high-risk thresholds for the three risk scores were treated with CVM, while 60-65% of men and 25-45% of women with scores above the high-risk thresholds received no treatment. Among women using CVM, only 2.2% (NORRISK, 4.4% (SCORE and 14.5% (Framingham had risk scores above the high-risk values. Low education, poor self-reported general health, muscular pains, mental distress (in females only and a family history of premature cardiovascular disease correlated with use of CVM. Elevated blood pressure was the single factor most strongly predictive of CVM treatment. Conclusion Prescription of CVM to middle-aged individuals by large seems to occur independently of estimated total cardiovascular risk, and this applies especially to females.

  19. Some properties of negative cloud-to-ground flashes from observations of a local thunderstorm based on accurate-stroke-count studies

    Science.gov (United States)

    Zhu, Baoyou; Ma, Ming; Xu, Weiwei; Ma, Dong

    2015-12-01

    Properties of negative cloud-to-ground (CG) lightning flashes, in terms of number of strokes per flash, inter-stroke intervals and the relative intensity of subsequent and first strokes, were presented by accurate-stroke-count studies based on all 1085 negative flashes from a local thunderstorm. The percentage of single-stroke flashes and stroke multiplicity evolved significantly during the whole life cycle of the study thunderstorm. The occurrence probability of negative CG flashes decreased exponentially with the increasing number of strokes per flash. About 30.5% of negative CG flashes contained only one stroke and number of strokes per flash averaged 3.3. In a subset of 753 negative multiple-stroke flashes, about 41.4% contained at least one subsequent stroke stronger than the corresponding first stroke. Subsequent strokes tended to decrease in strength with their orders and the ratio of subsequent to first stroke peaks presented a geometric mean value of 0.52. Interestingly, negative CG flashes of higher multiplicity tended to have stronger initial strokes. 2525 inter-stroke intervals showed a more or less log-normal distribution and gave a geometric mean value of 62 ms. For CG flashes of particular multiplicity geometric mean inter-stroke intervals tended to decrease with the increasing number of strokes per flash, while those intervals associated with higher order strokes tended to be larger than those associated with low order strokes.

  20. Cardiovascular risk management in patients with coronary heart disease in primary care: variation across countries and practices. An observational study based on quality indicators

    Directory of Open Access Journals (Sweden)

    van Lieshout Jan

    2012-10-01

    Full Text Available Abstract Background Primary care has an important role in cardiovascular risk management (CVRM and a minimum size of scale of primary care practices may be needed for efficient delivery of CVRM . We examined CVRM in patients with coronary heart disease (CHD in primary care and explored the impact of practice size. Methods In an observational study in 8 countries we sampled CHD patients in primary care practices and collected data from electronic patient records. Practice samples were stratified according to practice size and urbanisation; patients were selected using coded diagnoses when available. CVRM was measured on the basis of internationally validated quality indicators. In the analyses practice size was defined in terms of number of patients registered of visiting the practice. We performed multilevel regression analyses controlling for patient age and sex. Results We included 181 practices (63% of the number targeted. Two countries included a convenience sample of practices. Data from 2960 CHD patients were available. Some countries used methods supplemental to coded diagnoses or other inclusion methods introducing potential inclusion bias. We found substantial variation on all CVRM indicators across practices and countries. We computed aggregated practice scores as percentage of patients with a positive outcome. Rates of risk factor recording varied from 55% for physical activity as the mean practice score across all practices (sd 32% to 94% (sd 10% for blood pressure. Rates for reaching treatment targets for systolic blood pressure, diastolic blood pressure and LDL cholesterol were 46% (sd 21%, 86% (sd 12% and 48% (sd 22% respectively. Rates for providing recommended cholesterol lowering and antiplatelet drugs were around 80%, and 70% received influenza vaccination. Practice size was not associated to indicator scores with one exception: in Slovenia larger practices performed better. Variation was more related to differences between

  1. A comparative hospital-based observational study of mono- and co-infections of malaria, dengue virus and scrub typhus causing acute undifferentiated fever.

    Science.gov (United States)

    Ahmad, S; Dhar, M; Mittal, G; Bhat, N K; Shirazi, N; Kalra, V; Sati, H C; Gupta, V

    2016-04-01

    Positive serology for dengue and/or scrub typhus infection with/without positive malarial smear (designated as mixed or co-infection) is being increasingly observed during epidemics of acute undifferentiated febrile illnesses (AUFIs). We planned to study the clinical and biochemical spectrum of co-infections with Plasmodium sp., dengue virus and scrub typhus and compare these with mono-infection by the same organisms. During the period from December 2012 to December 2013, all cases presenting with AUFIs to a single medical unit of a referral centre in Garhwal region of the north Indian state of Uttarakhand were retrospectively selected and categorised aetiologically as co-infections, malaria, dengue or scrub typhus. The groups thus created were compared in terms of demographic, clinical, biochemical and outcome parameters. The co-infection group (n = 49) was associated with milder clinical manifestations, fewer, milder and non-progressive organ dysfunction, and lesser need for intensive care, mechanical ventilation and dialysis as compared to mono-infections. When co-infections were sub-grouped and compared with the relevant mono-infections, there were differences in certain haematological and biochemical parameters; however, this difference did not translate into differential outcomes. Scrub typhus mono-infection was associated with severe disease in terms of both morbidity and mortality. Malaria, dengue and scrub typhus should be routinely tested in all patients with AUFIs. Co-infections, whether true or due to serological cross-reactivity, appear to be a separate entity so far as presentation and morbidity is concerned. Further insight is needed into the mechanism and identification of the protective infection. PMID:26851948

  2. The NOAA Satellite Observing System Architecture Study

    Science.gov (United States)

    Volz, Stephen; Maier, Mark; Di Pietro, David

    2016-01-01

    NOAA is beginning a study, the NOAA Satellite Observing System Architecture (NSOSA) study, to plan for the future operational environmental satellite system that will follow GOES and JPSS, beginning about 2030. This is an opportunity to design a modern architecture with no pre-conceived notions regarding instruments, platforms, orbits, etc. The NSOSA study will develop and evaluate architecture alternatives to include partner and commercial alternatives that are likely to become available. The objectives will include both functional needs and strategic characteristics (e.g., flexibility, responsiveness, sustainability). Part of this study is the Space Platform Requirements Working Group (SPRWG), which is being commissioned by NESDIS. The SPRWG is charged to assess new or existing user needs and to provide relative priorities for observational needs in the context of the future architecture. SPRWG results will serve as input to the process for new foundational (Level 0 and Level 1) requirements for the next generation of NOAA satellites that follow the GOES-R, JPSS, DSCOVR, Jason-3, and COSMIC-2 missions.

  3. Universal HbA1c Measurement in Early Pregnancy to Detect Type 2 Diabetes Reduces Ethnic Disparities in Antenatal Diabetes Screening: A Population-Based Observational Study.

    Directory of Open Access Journals (Sweden)

    R C E Hughes

    Full Text Available In response to the type 2 diabetes epidemic, measuring HbA1c with the first-antenatal blood screen was recently recommended in NZ. This would enable prompt treatment of women with unrecognised type 2 diabetes, who may otherwise go undetected until the gestational diabetes (GDM screen. We compare inter-ethnic antenatal screening practices to examine whether the HbA1c test would be accessed by ethnicities most at risk of diabetes, and we determined the prevalence of unrecognised type 2 diabetes and prediabetes in our pregnant population. This is an observational study of pregnancies in Christchurch NZ during 2008-2010. Utilising electronic databases, we matched maternal characteristics to first-antenatal bloods, HbA1c, and GDM screens (glucose challenge tests and oral glucose tolerance tests. Overall uptake of the first-antenatal bloods versus GDM screening was 83.1% and 53.8% respectively in 11,580 pregnancies. GDM screening was lowest in Māori 39.3%, incidence proportion ratio (IPR 0.77 (0.71, 0.84 compared with Europeans. By including HbA1c with the first-antenatal bloods, the number screened for diabetes increases by 28.5% in Europeans, 40.0% in Māori, 28.1% in Pacific People, and 26.7% in 'Others' (majority of Asian descent. The combined prevalence of unrecognised type 2 diabetes and prediabetes by NZ criteria, HbA1c ≥5.9% (41mmol/mol, was 2.1% in Europeans, Māori 4.7% IPR 2.59 (1.71, 3.93, Pacific People 9.5% IPR 4.76 (3.10, 7.30, and 'Others' 6.2% IPR 2.99 (2.19, 4.07. Applying these prevalence data to 2013 NZ national births data, routine antenatal HbA1c testing could have identified type 2 diabetes in 0.44% and prediabetes in 3.96% of women. Routine HbA1c measurement in early pregnancy is an ideal screening opportunity, particularly benefitting vulnerable groups, reducing ethnic disparities in antenatal diabetes screening. This approach is likely to have world-wide relevance and applicability. Further research is underway to

  4. The study of seasonal composition and dynamics of wetland ecosystems and wintering bird habitat at Poyang Lake, PR China using object-based image analysis and field observations

    Science.gov (United States)

    Dronova, Iryna

    Wetlands are among the most productive ecosystems in the world which support critical ecological services and high biological diversity yet are vulnerable to climate change and human activities. In this thesis, I investigated the capabilities of satellite remote sensing with medium spatial resolution and object-based image analysis (OBIA) methods to elucidate seasonal composition and dynamics of wetland ecosystems and indicators of habitat for wintering waterbirds in a large conservation hotspot of Poyang Lake, PR China. I first examined changes in major wetland cover types during the low water period when Poyang Lake provides habitat to large numbers of migratory birds from the East Asian pathway. I used OBIA to map and analyze the transitions among water, vegetation, mudflat and sand classes from four 32-m Beijing-1 microsatellite images between late fall 2007 and early spring 2008. This analysis revealed that, while transitions among wetland classes were strongly associated with precipitation and flood-driven hydrological variation, the overall dynamics were a more complex interplay of vegetation phenology, disturbance and post-flood exposure. Remote sensing signals of environmental processes were more effectively captured by changes in fuzzy memberships to each class per location than by changes in spatial extents of the best-matching classes alone. The highest uncertainty in the image analysis corresponded to transitional wetland states at the end of the major flood recession in November and to heterogeneous mudflat areas at the land-water interface during the whole study period. Results suggest seasonally exposed mudflat features as important targets for future research due to heterogeneity and uncertainty of their composition, variable spatial distribution and sensitivity to hydrological dynamics. I further explored the potential of OBIA to overcome the limitations of the traditional pixel-based image classification methods in characterizing Poyang Lake

  5. Observer-based Satellite Attitude Control and Simulation Researches

    Institute of Scientific and Technical Information of China (English)

    王子才; 马克茂

    2002-01-01

    Observer design method is applied to the realization of satellite attitude control law baaed on simplified control model. Exact mathematical model of the satellite attitude control system is also constructed, together with the observer-based control law, to conduct simulation research. The simulation results justify the effectiveness andfeasibility of the observer-based control method.

  6. A LONGITUDINAL-STUDY OF INTERACTION PATTERNS OF A PSYCHIATRIST AND SEVERELY DEPRESSED-PATIENTS BASED ON OBSERVED BEHAVIOR - AN ETHOLOGICAL APPROACH OF INTERPERSONAL THEORIES OF DEPRESSION

    NARCIS (Netherlands)

    BOUHUYS, AL; VANDENHOOFDAKKER, RH

    1993-01-01

    Observed behaviour of a psychiatrist interacting with severely depressed patients during an interview was related to the course of depression during hospitalization. The behavioural structure of such interaction could be described by 6 factors for the patients and 7 factors for the psychiatrist. The

  7. Overview of the Ocean Observer Satellite Study

    Science.gov (United States)

    Cunningham, J. D.; McGuire, J. P.; Pichel, W. G.; Gerber, A. J.

    2002-12-01

    A two-year study of ocean satellite remote sensing requirements and instrument/satellite options is nearing completion. This Ocean Observer Study was sponsored by the U.S. Dept. of Commerce/Dept. of Defense/National Aeronautics and Space Administration Integrated Program Office, whose mission is to develop the future U.S. National Polar-Orbiting Operational Environmental Satellite System (NPOESS). A comprehensive Ocean Observer User Requirements Document has been drafted by a team of over 150 government, academic, and private sector scientists, engineers, and administrators. Included are requirements for open and coastal ocean surface, cryospheric, hydrologic, and some land/hazard and atmospheric boundary layer parameters. This document was then used as input to the instrument and satellite study (conducted by the Jet Propulsion Laboratory) which produced five different instrument/satellite configuration options designed to address the maximum number of requirements which will not be met with the already-approved NPOESS instruments. Instruments studied include a synthetic aperture radar (SAR), an altimeter, and a hyper-spectral coastal infrared/visible imager. After analyzing the alternatives, it appears that one of the best options is a two-satellite system consisting of (1) an altimeter mission in the Topex/Poseidon orbit carrying both wide-swath and delayed doppler altimeters, and (2) a multi-polarization, multi-frequency, multi-mode interferometric SAR mission including a coastal imager in a polar sun-synchronous orbit. This paper summarizes the user requirements process, briefly describes the notional satellite configuration, and presents some of the capabilities of the instruments.

  8. Estimating Evapotranspiration Using an Observation Based Terrestrial Water Budget

    Science.gov (United States)

    Rodell, Matthew; McWilliams, Eric B.; Famiglietti, James S.; Beaudoing, Hiroko K.; Nigro, Joseph

    2011-01-01

    Evapotranspiration (ET) is difficult to measure at the scales of climate models and climate variability. While satellite retrieval algorithms do exist, their accuracy is limited by the sparseness of in situ observations available for calibration and validation, which themselves may be unrepresentative of 500m and larger scale satellite footprints and grid pixels. Here, we use a combination of satellite and ground-based observations to close the water budgets of seven continental scale river basins (Mackenzie, Fraser, Nelson, Mississippi, Tocantins, Danube, and Ubangi), estimating mean ET as a residual. For any river basin, ET must equal total precipitation minus net runoff minus the change in total terrestrial water storage (TWS), in order for mass to be conserved. We make use of precipitation from two global observation-based products, archived runoff data, and TWS changes from the Gravity Recovery and Climate Experiment satellite mission. We demonstrate that while uncertainty in the water budget-based estimates of monthly ET is often too large for those estimates to be useful, the uncertainty in the mean annual cycle is small enough that it is practical for evaluating other ET products. Here, we evaluate five land surface model simulations, two operational atmospheric analyses, and a recent global reanalysis product based on our results. An important outcome is that the water budget-based ET time series in two tropical river basins, one in Brazil and the other in central Africa, exhibit a weak annual cycle, which may help to resolve debate about the strength of the annual cycle of ET in such regions and how ET is constrained throughout the year. The methods described will be useful for water and energy budget studies, weather and climate model assessments, and satellite-based ET retrieval optimization.

  9. Motion based parsing for video from observational psychology

    Science.gov (United States)

    Kokaram, Anil; Doyle, Erika; Lennon, Daire; Joyeux, Laurent; Fuller, Ray

    2006-01-01

    In Psychology it is common to conduct studies involving the observation of humans undertaking some task. The sessions are typically recorded on video and used for subjective visual analysis. The subjective analysis is tedious and time consuming, not only because much useless video material is recorded but also because subjective measures of human behaviour are not necessarily repeatable. This paper presents tools using content based video analysis that allow automated parsing of video from one such study involving Dyslexia. The tools rely on implicit measures of human motion that can be generalised to other applications in the domain of human observation. Results comparing quantitative assessment of human motion with subjective assessment are also presented, illustrating that the system is a useful scientific tool.

  10. AECL's excavation stability study - summary of observations

    International Nuclear Information System (INIS)

    The Excavation Stability Study (ESS) was conducted at the 420 Level of the Underground Research Laboratory (URL) to evaluate stability and the extent of excavation damage in tunnels as a function of tunnel geometry and orientation, geology, and excavation method. A series of ovaloid and circular openings were used to achieve different boundary stress levels and near-field stress distributions to assess the effect of tunnel geometry on damage development. Several of these openings had sections in both granite and granodiorite lithology, providing a comparison of damage in rock types with different strength characteristics. Damage around circular tunnels (one excavated by drill-and-blast, the other by mechanical means) was also investigated. The study.showed that mechanically stable openings can be excavated in the most adverse stress conditions at the 420 Level of the URL. In addition, it was shown that tunnel stability is sensitive to tunnel shape, variations in geology, and to some extent, the excavation method. Findings of the study are relevant in developing design criteria, and in assessing the feasibility of constructing large ovaloid openings in adverse stress conditions. This report summarizes the preliminary observations related to tunnel stability and excavation damage. (author). 8 refs., 7 tabs., 23 figs

  11. Electronic health record-based assessment of oral corticosteroid use in a population of primary care patients with asthma: an observational study

    OpenAIRE

    Allen-Ramey, Felicia C; Nelsen, Linda M; Leader, Joseph B; Mercer, Dione; Kirchner, Henry Lester; Jones, James B

    2013-01-01

    Background Oral corticosteroid prescriptions are often used in clinical studies as an indicator of asthma exacerbations. However, there is rarely the ability to link a prescription to its associated diagnosis. The objective of this study was to characterize patterns of oral corticosteroid prescription orders for asthma patients using an electronic health record database, which links each prescription order to the diagnosis assigned at the time the order was placed. Methods This was a retrospe...

  12. Age at Menarche, Level of Education, Parity and the Risk of Hysterectomy: A Systematic Review and Meta-Analyses of Population-Based Observational Studies.

    Directory of Open Access Journals (Sweden)

    Louise F Wilson

    Full Text Available Although rates have declined, hysterectomy is still a frequent gynaecological procedure. To date, there has been no systematic quantification of the relationships between early/mid-life exposures and hysterectomy. We performed a systematic review and meta-analyses to quantify the associations between age at menarche, education level, parity and hysterectomy.Eligible studies were identified by searches in PubMed and Embase through March 2015. Study-specific estimates were summarised using random effects meta-analysis. Heterogeneity was explored using sub-group analysis and meta-regression.Thirty-two study populations were identified for inclusion in at least one meta-analysis. Each year older at menarche was associated with lower risk of hysterectomy-summary hazard ratio 0.86 (95% confidence interval: 0.78, 0.95; I2 = 0%; summary odds ratio 0.88 (95% confidence interval: 0.82, 0.94; I2 = 61%. Low education levels conferred a higher risk of hysterectomy in the lowest versus highest level meta-analysis (summary hazard ratio 1.87 (95% confidence interval: 1.25, 2.80; I2 = 86%, summary odds ratio 1.51 (95% confidence interval: 1.35, 1.69; I2 = 90% and dose-response meta-analysis (summary odds ratio 1.17 (95% confidence interval: 1.12, 1.23; I2 = 85% per each level lower of education. Sub-group analysis showed that the birth cohort category of study participants, the reference category used for level of education, the year the included article was published, quality of the study (as assessed by the authors and control for the key variables accounted for the high heterogeneity between studies in the education level meta-analyses. In the meta-analyses of studies of parity and hysterectomy the results were not statistically significant.The present meta-analyses suggest that the early life factors of age at menarche and lower education level are associated with hysterectomy, although this evidence should be interpreted with some caution due to variance

  13. Tropical cyclone-ocean interaction in Typhoon Megi (2010)—A synergy study based on ITOP observations and atmosphere-ocean coupled model simulations

    Science.gov (United States)

    Wu, Chun-Chieh; Tu, Wei-Tsung; Pun, Iam-Fei; Lin, I.-I.; Peng, Melinda S.

    2016-01-01

    A mesoscale model coupling the Weather Research and Forecasting model and the three-dimensional Price-Weller-Pinkel ocean model is used to investigate the dynamical ocean response to Megi (2010). It is found that Megi induces sea surface temperature (SST) cooling very differently in the Philippine Sea (PS) and the South China Sea (SCS). The results are compared to the in situ measurements from the Impact of Typhoons on the Ocean in the Pacific (ITOP) 2010 field experiment, satellite observations, and ocean analysis field from Eastern Asian Seas Ocean Nowcast/Forecast System of the U.S. Naval Research Laboratory. The uncoupled and coupled experiments simulate relatively accurately the track and intensity of Megi over PS; however, the simulated intensity of Megi over SCS varies significantly among the experiments. Only the experiment coupled with three-dimensional ocean processes, which generates rational SST cooling, reasonably simulates the storm intensity in SCS. Our results suggest that storm translation speed and upper ocean thermal structure are two main factors responsible for Megi's distinct different impact over PS and over SCS. In addition, it is shown that coupling with one-dimensional ocean process (i.e., only vertical mixing process) is not enough to provide sufficient ocean response, especially under slow translation speed (~2-3 m s-1), during which vertical advection (or upwelling) is significant. Therefore, coupling with three-dimensional ocean processes is necessary and crucial for tropical cyclone forecasting. Finally, the simulation results show that the stable boundary layer forms on top of the Megi-induced cold SST area and increases the inflow angle of the surface wind.

  14. Bumpless Transfer between Observer-based Gain Scheduled Controllers

    DEFF Research Database (Denmark)

    Bendtsen, Jan Dimon; Stoustrup, Jakob; Trangbæk, Klaus

    2005-01-01

    This paper deals with bumpless transfer between a number of observer-based controllers in a gain scheduling architecture. Linear observer-based controllers are designed for a number of linear approximations of a nonlinear system in a set of operating points, and gain scheduling control can subseq...

  15. Simulating Observer in Supervisory Control- A Domain-based Method

    Directory of Open Access Journals (Sweden)

    Seyed Morteza Babamir

    2012-06-01

    Full Text Available An Observer in the supervisory control observes responses of a discrete system to events of its environment and reports an unsafe/ critical situation if the response is undesired. An undesired response from the system indicates the system response does not adhere to users’ requirements of the system. Therefore, events and conditions of the system environment and user’s requirements of the system are basic elements to observer in determining correctness of the system response. However, the noteworthy matter is that the events, conditions, and requirements should be defined based on data of problem domain because discrete data are primary ingredients of the environment in discrete systems and they are used by system users as a gauge to express their requirements playing a vital role in safety-critical systems, such as medical and avionic ones. A large quantity of methods has already been proposed to model and simulate supervisory control of discrete systems however, a systematic method relying on data of problem domain is missing. Having extracted events, conditions, and user’s requirements from data of problem domain, a Petri-Net automaton is constructed for identifying violation of user’s requirements. The net constitutes the core of the observer and it is used to identify undesired responses of the system. In the third step, run-time simulation of the observer is suggested using multithreading mechanism and Task Parallel Library (TPL technology of Microsoft. Finally, a case study of a discrete concurrent system is proposed, the method applied and simulation results are analyzed based on the system implementation on a multi-core computer.

  16. General practice variation in spirometry testing among patients receiving first-time prescriptions for medication targeting obstructive lung disease in Denmark: a population-based observational study

    OpenAIRE

    Koefoed, Mette M; Søndergaard, Jens; Christensen, René dePont; Jarbøl, Dorte E

    2013-01-01

    Background Spirometry testing is essential to confirm an obstructive lung disease, but studies have reported that a large proportion of patients diagnosed with COPD or asthma have no history of spirometry testing. Also, it has been shown that many patients are prescribed medication for obstructive lung disease without a relevant diagnosis or spirometry test registered. General practice characteristics have been reported to influence diagnosis and management of several chronic diseases. Howeve...

  17. Factors affecting well-being and socio-occupational functioning in schizophrenia patients following an acute exacerbation: A hospital based observational study

    Directory of Open Access Journals (Sweden)

    Roopa Gopalakrishnan

    2015-01-01

    Full Text Available Background: Improving functioning levels are an important goal of treatment in schizophrenia. Most studies have described long-term course and outcome in schizophrenia. However, understanding factors influencing functioning in the immediate recovery period following an acute exacerbation may be of important clinical relevance. Aim: The aim of this study is to assess the factors that influence well-being and socio-occupational functioning following an acute exacerbation in schizophrenia patients. Materials and Methods: The study included 40 patients during the period from June 2013 to June 2014. The possible effect of gender, duration of illness, duration of untreated psychosis, premorbid adjustment, cognitive impairment, facial affect perception and treatment compliance on well-being, and socio-occupational functioning was examined. Results : About 45% of the individuals experienced below average well-being. On logistic regression analysis poor compliance with medication and poorer cognitive functioning significantly differentiated the patient group with below average well-being from those with an above average well-being. Male gender, poor premorbid adjustment, poor compliance to treatment, poor cognitive functioning, and greater duration of untreated psychosis were found to be associated with a poorer socio-occupational functioning. Conclusion: Clinical interventions focusing on improving cognitive impairment and compliance to treatment could play a role in improving well-being, and socio-occupational functioning in schizophrenia patients following an acute exacerbation.

  18. Influence of seabed topography on the distribution of manganese nodules and associated features in the Central Indian Basin: A study based on photographic observations

    Digital Repository Service at National Institute of Oceanography (India)

    Sharma, R.; Kodagali, V.N.

    are the highest along the slopes (average= 15.3% coverage, 4.0 kg/m 2 abundance in photo and 6.7 kg/m 2 in grabs); and the crests of the seamounts and abyssal hills (average= 12.3%, 3.5 kg/m 2 and 5.5 kg/m 2) and least in the abyssal plains (1.4%, 0.8 kg/m 2...% Fig. 4. Distribution of nodules (coverage) and rock outcrops in the study area. TABLE 1 Details of nodule parameters in different topographic settings Setting Depth Nodule Photo Grab Relative coverage abundance abundance abundance (m) (%) (kg/m 2...

  19. Forbush Decrease Prediction Based on Remote Solar Observations

    Science.gov (United States)

    Dumbović, M.; Vršnak, B.; Čalogović, J.

    2016-01-01

    We employ remote observations of coronal mass ejections (CMEs) and the associated solar flares to forecast the CME-related Forbush decreases, i.e. short-term depressions in the galactic cosmic-ray flux. The relation between the Forbush effect at Earth and remote observations of CMEs and associated solar flares is studied via a statistical analysis. Relations between Forbush decrease magnitude and several CME/flare parameters were found: the initial CME speed, apparent width, source position, associated solar-flare class, and the effect of successive-CME occurrence. Based on the statistical analysis, remote solar observations are employed to forecast a Forbush-decrease. For this purpose, an empirical probabilistic model is constructed that uses selected remote solar observations of the CME and associated solar flare as input and gives the expected Forbush-decrease magnitude range as output. The forecast method is evaluated using several verification measures, indicating that as the forecast tends to be more specific, it is less reliable, which is its main drawback. However, the advantages of the method are that it provides an early prediction and that the input does not necessarily depend on using a spacecraft.

  20. The positive role of breastfeeding on infant health during the first 6 weeks: findings from a prospective observational study based on maternal reports.

    LENUS (Irish Health Repository)

    Tarrant, R C

    2012-03-01

    This study aimed to report on adverse infant and maternal clinical outcomes, and investigate the relationship between infant feeding practice and such adverse clinical outcomes in infants during the first 6 weeks postpartum. From an eligible sample of 450 mother-term infant pairs recruited from the Coombe Women and Infants University Hospital in Dublin, 27.1% of infants (n=122) were maternally reported to have had an illness during the first 6 weeks that necessitated the provision of prescribed medication +\\/- general practitioner\\/paediatrician attendance +\\/- hospitalisation. Of these, 90 infants had > or =1 episode of infection +\\/- viral +\\/- gastro-intestinal-related condition. After adjustment, \\'any\\' breastfeeding to 6 weeks was protective against such adverse infant outcomes (adjusted odds ratio [aOR] 0.44, P = 0.022). Attendance to the GP\\/paediatrician for > 1 visit (aOR 3.44, P = 0.000) and multiparity (aOR 1.76, P = 0.041) were also positively associated with such adverse infant outcomes. To decrease infant morbidity rates in Ireland, government investment in breastfeeding promotion, support and research should be a continued public health priority.

  1. Observables for identity-based tachyon vacuum solutions

    International Nuclear Information System (INIS)

    We consider a modified KBc algebra in bosonic open string field theory expanded around identity-based scalar solutions. By use of the algebra, classical solutions on the background are constructed and observables for them, including energy densities and gauge-invariant overlaps, are calculable. These results are applied to evaluate observables analytically for both the identity-based trivial pure gauge solution and the identity-based tachyon vacuum solution

  2. Observed bodies generate object-based spatial codes.

    Science.gov (United States)

    Taylor, Alison; Flynn, Maria; Edmonds, Caroline J; Gardner, Mark R

    2016-09-01

    Contemporary studies of spatial and social cognition frequently use human figures as stimuli. The interpretation of such studies may be complicated by spatial compatibility effects that emerge when researchers employ spatial responses, and participants spontaneously code spatial relationships about an observed body. Yet, the nature of these spatial codes - whether they are location- or object-based, and coded from the perspective of the observer or the figure - has not been determined. Here, we investigated this issue by exploring spatial compatibility effects arising for objects held by a visually presented whole-bodied schematic human figure. In three experiments, participants responded to the colour of the object held in the figure's left or right hand, using left or right key presses. Left-right compatibility effects were found relative to the participant's egocentric perspective, rather than the figure's. These effects occurred even when the figure was rotated by 90° to the left or to the right, and the coloured objects were aligned with the participant's midline. These findings are consistent with spontaneous spatial coding from the participant's perspective and relative to the normal upright orientation of the body. This evidence for object-based spatial coding implies that the domain general cognitive mechanisms that result in spatial compatibility effects may contribute to certain spatial perspective-taking and social cognition phenomena. PMID:27235754

  3. International Siberian Shelf Study 2008 (ISSS-08): The major IPY ship-based program along the entire Eurasian-Arctic continental shelf with combined biogeochemical and geophysical observations

    Science.gov (United States)

    Semiletov, I.; Gustaffson, O.; Dudarev, O.; Andersson, P.; Salyuk, A.; Andersson, L.; Shakhova, N.

    2008-12-01

    The coastal margin north of Eurasia is the world's largest continental shelf. It provides an important regime for transport and processing of heat, freshwater and carbon between its Siberian drainage basins and the high Arctic Ocean. There are gradients in climate and carbon dynamics along the Barents, Kara, Laptev, East Siberian, and Chuckchi Sea conduits. The continent-scale system is characterized by strong discharge through the Great Russian Arctic Rivers, onshore and offshore-subsea permafrost with massive shallow methane deposits, eroding carbon-rich coasts, and shelf-feeding of the Arctic halocline. The region is of particular interest from the perspective of carbon-climate couplings. Surface air temperature anomalies for 2000--2005 in the East Siberia are about 4°C higher than preceding 30-year average. Hence, there is a potential for remobilization of 'old' terrestrial carbon from thawing tundra permafrost and coastal-ice complexes as well as methane release from subsea permafrost. The role of climate warming on shelf-derived halocline waters has also yet to be elucidated. The 50-day Russia-Sweden-USA expedition onboard H/V Jacob Smirnitsky presented a golden opportunity to shed lights on these issues. A second ISSS-08 component investigated in detail the Lena river and the shallow Laptev Sea. The ISSS-08 had a particular geographical focus on the Laptev, East Siberian and Russian-sector of Chukchi Sea as this is the most enigmatic and under-sampled region in the Arctic ocean. A multitude of complementary studies were carried out. Underway sampling of 4 m seawater was continuously monitored for a broad range of geophysical and biogeochemical parameters; air was continuously sampled for CH4 stable isotopes, aerosols and met properties including air-sea CO2 and CH4 turbulent fluxes . Detailed stations for sediment, water, and air were occupied off the river mouths of Ob, Yenisey, Lena, Indigirka and Kolyma. Five polygons outside sites of intense coastal

  4. Neuronal bases of structural coherence in contemporary dance observation.

    Science.gov (United States)

    Bachrach, Asaf; Jola, Corinne; Pallier, Christophe

    2016-01-01

    The neuronal processes underlying dance observation have been the focus of an increasing number of brain imaging studies over the past decade. However, the existing literature mainly dealt with effects of motor and visual expertise, whereas the neural and cognitive mechanisms that underlie the interpretation of dance choreographies remained unexplored. Hence, much attention has been given to the action observation network (AON) whereas the role of other potentially relevant neuro-cognitive mechanisms such as mentalizing (theory of mind) or language (narrative comprehension) in dance understanding is yet to be elucidated. We report the results of an fMRI study where the structural coherence of short contemporary dance choreographies was manipulated parametrically using the same taped movement material. Our participants were all trained dancers. The whole-brain analysis argues that the interpretation of structurally coherent dance phrases involves a subpart (superior parietal) of the AON as well as mentalizing regions in the dorsomedial prefrontal cortex. An ROI analysis based on a similar study using linguistic materials (Pallier et al., 2011) suggests that structural processing in language and dance might share certain neural mechanisms. PMID:26348557

  5. Observation of Transient Measurement with a Silica long base Tiltmeter

    Science.gov (United States)

    Boudin, F.; Bernard, P.; Longuevergne, L.; Florsch, N.; Chery, J.; Olcay, M.; Larmat, C.; Boy, J.; Esnoult, M.; Kammenthaler, M.; Vincent, T.

    2008-12-01

    Tilt measurements allow us to observe the crustal flexure which is produced by a large range of loading processes, such as hydrological or atmospheric loadings, or tectonic loading or the weight of the moving water column during tsunamis. Proposing a detailed process at the origin of transient events requires much more minute observations than are available today. Most of the predictions for the amplitude of these transient signals point out that very weak signals must be indeed detected. It is ever more difficult for the smallest events which could be numerous at depth. An instrumental resolution much better than 0.1 µrad is required at least for the strain. This is clearly out of reach for both GPS and inSAR approaches. Our objective is to obtain tiltmetric data with a resolution better or equal than 0.001 microrad, and long term precision ranging from 0.1 microrad to 0.01 microrad by year. We have developed a silica long base tiltmeter to study hydrological load or pressure effect and to study the seismic cycle. We show the results of two 100 m silica water tube tiltmeters which were installed in a mine in the French Vosges massif in the framework of a hydrology research project and too tectonic research. This instruments show a remarkably good stability (0.0065 microrad by month) and a low noise level (of the order of 0.00001 microrad). Toroidal and speroidal free modes of the Earth were observed after the two last major events on Sumatra. In the same project we installed 4 others tiltmeters stations. In the Morbihan to study the confined aquifer of Ploemeur or to study the hydrological Karst effect in the Larzac area (Herault) or Calern (Alpes Maritimes). The Last tiltmetric station is in the North Chile in the seismic gap zone. On this station we are able to observe the tsunamis wave produced by the last Tocopilla earthquake (M7.8), many cosismic signal and we think, we are able to observe the tectonic load.

  6. Disturbance Observer Based Control of Small Unmanned Aerial Rotorcraft

    Directory of Open Access Journals (Sweden)

    Xusheng Lei

    2013-01-01

    Full Text Available As a complex system, the control performance of small unmanned aerial rotorcraft is easily affected by the dynamic model errors, measurement errors, and environment disturbances. This paper proposes a disturbance observer based control method to improve performance. The disturbance observer based control is constructed by the feedback control and a series of integral filters. The system stability can be guaranteed by the feedback control method. Furthermore, the disturbances can be estimated and eliminated quickly by the integral filters. Therefore, the control performance can be improved effectively. The control performance of the disturbance observer based control has been validated by a series of flight tests. Compared with feedback control, the disturbance observer based control yields a better tracking performance in the presence of disturbances.

  7. Variance-based uncertainty relations for incompatible observables

    Science.gov (United States)

    Chen, Bin; Cao, Ning-Ping; Fei, Shao-Ming; Long, Gui-Lu

    2016-06-01

    We formulate uncertainty relations for arbitrary finite number of incompatible observables. Based on the sum of variances of the observables, both Heisenberg-type and Schrödinger-type uncertainty relations are provided. These new lower bounds are stronger in most of the cases than the ones derived from some existing inequalities. Detailed examples are presented.

  8. Magnetosheath cavities: case studies using Cluster observations

    OpenAIRE

    Katırcıoğlu, F. T.; Z. Kaymaz; D. G. Sibeck; Dandouras, I.

    2009-01-01

    This paper presents examples of magnetosheath cavities in Cluster spacecraft observations. The cavities are accompanied by high energy particles in the magnetosheath and characterized by depressed magnetic fields and densities. Flow speeds decrease and temperatures increase within the cavities. All magnetosheath parameters show increased variability within the cavities when the energetic particle flux is high. We predict outward motion of the magnetopause boundary in respons...

  9. Interstellar dust: interfacing laboratory, theoretical and observational studies

    Science.gov (United States)

    Jones, Anthony Peter

    2015-08-01

    In this talk I will consider how our understanding of interstellar dust can only be advanced through a combination of laboratory, theoretical and observational studies, which provide the critical framework for advancing our understanding. I will summarise what we currently know, or think we know, about the physical and compositional properties of dust and their evolution in interstellar media. Along the way I will question the utility of astronomical dust analogues and show, based on data from the laboratory, theoretical studies and from astronomical observations, that some of our prior interpretations need to be subjected to a critical re-evaluation. I will present interstellar dust modelling from a new vantage point and review ideas on the interpretation of observations within the framework of this model and its predictions for dust evolution within and between interstellar media. Finally, I will summarise some of the current outstanding issues and what we would like to learn in the future.

  10. Structural control design based on reduced-order observer

    Science.gov (United States)

    Su, Tzu-Jeng; Craig, Roy R., Jr.

    1991-01-01

    An observer-based structural control design method is proposed in this paper. The method is a semi-inverse design procedure in that the control law is not designed before the observer system, but is a result that comes from the observer design. However, the observer design is not completely independent of the control design either, but seeks to yield a control law that is close to a prescribed control law. First, the observer design problem is considered as the reconstruction of a linear function of the state vector. The linear state function to be reconstructed is the given control law. Then, based on the derivation for linear state function observers, the observer design is formulated as a parameter optimization problem. The optimization objective is to generate a matrix that is close to the optimal feedback gain matrix. Based on that matrix, the form of the observer and a new control law can be determined. The semi-inverse design procedure can yield a reduced-order observer with dimension considerably smaller than that of the system. Two examples are used to demonstrate the proposed design procedure.

  11. The new worlds observer: The astrophysics strategic mission concept study

    Directory of Open Access Journals (Sweden)

    Cash W.

    2011-07-01

    Full Text Available We present some results of the Astrophysics Strategic Mission Concept Study for the New Worlds Observer (NWO. We show that the use of starshades is the most effective and affordable path to mapping and understanding our neighboring planetary systems, to opening the search for life outside our solar system, while serving the needs of the greater astronomy community. A starshade-based mission can be implemented immediately with a near term program of technology demonstration.

  12. The new worlds observer: The astrophysics strategic mission concept study

    Science.gov (United States)

    Cash, W.

    2011-07-01

    We present some results of the Astrophysics Strategic Mission Concept Study for the New Worlds Observer (NWO). We show that the use of starshades is the most effective and affordable path to mapping and understanding our neighboring planetary systems, to opening the search for life outside our solar system, while serving the needs of the greater astronomy community. A starshade-based mission can be implemented immediately with a near term program of technology demonstration.

  13. Weight-Based Victimization toward Overweight Adolescents: Observations and Reactions of Peers

    Science.gov (United States)

    Puhl, Rebecca M.; Luedicke, Joerg; Heuer, Cheslea

    2011-01-01

    Background: Weight-based victimization has become increasingly reported among overweight youth, but little is known about adolescents' perceptions and observations of weight-based teasing and bullying. This study examined adolescents' observations of and reactions to weight-based victimization toward overweight students at school. Methods:…

  14. Observation Study of Aerosol Radiative Properities over China

    Institute of Scientific and Technical Information of China (English)

    MAO Jietai; LI Chengcai

    2006-01-01

    With a simplified radiation balance model, study is performed of aerosol direct radiation forcing in relation to its optical properties and surface reflectance, indicating that with the thickened aerosol layer the earth-atmosphere system may increase or weaken the solar radiation albedo, depending upon different combinations of aerosol single scattering albedo (SSA, ω0), asymmetry factor (g), and surface albedo (αg)rather than relying directly on the aerosol optical depth (δ), which has its value just in proportion to the changed range of albedo alone.As indicated by the model results, systematic observations of aerosol radiative properties are required to make quantitative study of aerosol direct radiative forcing. Observational research of the properties has been undertaken based on ground and space measurements over China, including ground-based sunphotometeraerosol optical depth (AOD), nephelometer-aerosol scattering coefficients, aethalometer-aerosol absorption coefficients, and MODIS products-retrieved AOD. The satellite retrieved AOD is validated against in situ sun photometer measured AOD, ind icating that for eastern China remote sensing given AODs are acceptable owing mainly to lower surface reflectance there whereas for poor vegetation in the north of China the surface reflectance may be underestimated in AOD retrieval. However, appropriate modification of the scheme of aerosol remote sensing is likely to improve the retrieval accuracy. The aerosol single scattering albedo in dry condition is around 0.80 from surface-measured scattering and absorption coefficients. It requires further studies based on more observations to improve our understanding of the issue.

  15. Observational Study of Solar Magnetic Active Phenomena

    Indian Academy of Sciences (India)

    Hongqi Zhang

    2006-06-01

    The electric current separated into two parts reflected the quantative properties of heterogeneity and chirality of magnetic field, and defined them as the shear and twist components of current. We analyze the basic configuration and evolution of superactive region NOAA 6580-6619-6659. It is found that the contribution of the twist component of current cannot be reflected in the normal analysis of the magnetic shear and gradient of the active regions. The observational evidence of kink magnetic ropes generated from the subatmosphere cannot be found completely in some super delta active regions.

  16. Effectiveness of the Homeopathic Preparation Neurexan® Compared with that of Commonly used Valerian-Based Preparations for the Treatment of Nervousness/Restlessness – an Observational Study

    Directory of Open Access Journals (Sweden)

    Rainer Hubner

    2009-01-01

    Full Text Available Mild anxieties, nervousness, and restlessness are common in the general population and are commonly treated by complementary and alternative medical (CAM therapies. A prospective, nonrandomized, noninterventional, observational study, using conventional or CAM practices, was conducted in 49 German practices. Each practice could include up to 15 subjects treated with either the homeopathic preparation Neurexan® or with combination formulations based on valerian extracts. There was no placebo group. Choice and doses of study therapies were at the respective physician's discretion. The planned treatment duration was 2 weeks. A total of 826 subjects were included in the study and 777 (553 Neurexan and 224 valerian subjects were available for the final examination. Subjects receiving Neurexan tended to weigh less, to have fewer concomitant illnesses and slightly milder severity of nervousness/restlessness, and were likelier to be female than the subjects receiving valerian therapies. The summary score for nervousness/restlessness was reduced from 19.0 ± 6.1 at baseline to 7.4 ± 6.8 at the end of the observation period in the Neurexan group, a reduction of 11.5 ± 7.3 score units. In the valerian group, the summary score was reduced from 21.4 ± 6.0 to 12.6 ± 7.3, a reduction of 9.0 ± 6.6 score units. The changes from baseline and the differences between the groups were statistically significant. Similar significant differences in effects were seen on the subscores and on the subjects' assessments of effectiveness. Both study therapies were well tolerated. Neurexan appears to be an effective and well-tolerated alternative to valerian-based combination therapies for the treatment of nervousness/restlessness in subjects favorable towards a CAM-based therapy.

  17. Geomagnetic Observations for Main Field Studies

    DEFF Research Database (Denmark)

    Matzka, Jürgen; Chulliat, A.; Mandea, M.;

    2010-01-01

    Direct measurements of the geomagnetic field have been made for more than 400 years, beginning with individual determinations of the angle between geographic and magnetic North. This was followed by the start of continuous time series of full vector measurements at geomagnetic observatories...... and the beginning of geomagnetic repeat stations surveys in the 19th century. In the second half of the 20th century, true global coverage with geomagnetic field measurements was accomplished by magnetometer payloads on low-Earth-orbiting satellites. This article describes the procedures and instruments...... for magnetic field measurements on ground and in space and covers geomagnetic observatories, repeat stations, automatic observatories, satellites and historic observations. Special emphasis is laid on the global network of geomagnetic observatories....

  18. Ground-based observations of Kepler asteroseismic targets

    CERN Document Server

    Uytterhoeven, K; Southworth, J; Randall, S; Ostensen, R; Molenda-Zakowicz, J; Marconi, M; Kurtz, D W; Kiss, L; Gutierrez-Soto, J; Frandsen, S; De Cat, P; Bruntt, H; Briquet, M; Zhang, X B; Telting, J H; Steslicki, M; Ripepi, V; Pigulski, A; Paparo, M; Oreiro, R; Choong, Ngeow Chow; Niemczura, E; Nemec, J; Narwid, A; Mathias, P; Martin-Ruiz, S; Lehman, H; Kopacki, G; Karoff, C; Jackiewicz, J; Henden, A A; Handler, G; Grigachene, A; Green, E M; Garrido, R; Machado, L Fox; Debosscher, J; Creevey, O L; Catanzaro, G; Bognar, Z; Biazzo, K; Bernabei, S

    2010-01-01

    We present the ground-based activities within the different working groups of the Kepler Asteroseismic Science Consortium (KASC). The activities aim at the systematic characterization of the 5000+ KASC targets, and at the collection of ground-based follow-up time-series data of selected promising Kepler pulsators. So far, 35 different instruments at 30 telescopes on 22 different observatories in 12 countries are in use, and a total of more than 530 observing nights has been awarded. (Based on observations made with the Isaac Newton Telescope, William Herschel Telescope, Nordic Optical Telescope, Telescopio Nazionale Galileo, Mercator Telescope (La Palma, Spain), and IAC-80 (Tenerife, Spain). Also based on observations taken at the observatories of Sierra Nevada, San Pedro Martir, Vienna, Xinglong, Apache Point, Lulin, Tautenburg, Loiano, Serra la Nave, Asiago, McDonald, Skinakas, Pic du Midi, Mauna Kea, Steward Observatory, Bialkow Observatory of the Wroclaw University, Piszkesteto Mountain Station, Observato...

  19. What Is Popular Music Studies? Some Observations

    Science.gov (United States)

    Cloonan, Martin

    2005-01-01

    Popular Music Studies (PMS) is now taught in over 20 higher education institutions (HEIs) in the UK and numerous others across the world. This article outlines the constituent parts of PMS in the UK and questions its status as a discipline in its own right. It concludes by arguing that, having established itself, PMS will need to deal with two key…

  20. Developing ontologies in OWL: An observational study

    OpenAIRE

    Dzbor, Martin; Motta, Enrico; Buil-Aranda, C.; Gómez-Pérez, José Manuel; Görlitz, Olaf; Lewen, Holger

    2006-01-01

    As is known in the human-computer interaction (HCI) domain, interactions involve the user, the technology, and the ways they work together. We expand these notions to human-ontology interaction with the aim to investigate how users interact with the networked ontologies in a realistic ontology lifecycle. In this paper, we describe a user study that we have carried out in order to improve our understanding of the level of support provided by current ontology engineering tools in the context en...

  1. Solar Activity Studies using Microwave Imaging Observations

    CERN Document Server

    Gopalswamy, Nat

    2016-01-01

    We report on the status of solar cycle 24 based on polar prominence eruptions (PEs) and microwave brightness enhancement (MBE) information obtained by the Nobeyama radioheliograph. The north polar region of the Sun had near-zero field strength for more than three years (2012 to 2015) and ended only in September 2015 as indicated by the presence of polar PEs and the lack of MBE. The zero-polar-field condition in the south started only around 2013, but it ended by June 2014. Thus the asymmetry in the times of polarity reversal switched between cycle 23 and 24. The polar MBE is a good proxy for the polar magnetic field strength as indicated by the high degree of correlation between the two. The cross-correlation between the high- and low-latitude MBEs is significant for a lag of ~5.5 to 7.3 years, suggesting that the polar field of one cycle indicates the sunspot number of the next cycle in agreement with the Babcock-Leighton mechanism of solar cycles. The extended period of near-zero field in the north-polar re...

  2. Solar Activity Studies using Microwave Imaging Observations

    Science.gov (United States)

    Gopalswamy, N.

    2016-01-01

    We report on the status of solar cycle 24 based on polar prominence eruptions (PEs) and microwave brightness enhancement (MBE) information obtained by the Nobeyama radioheliograph. The north polar region of the Sun had near-zero field strength for more than three years (2012-2015) and ended only in September 2015 as indicated by the presence of polar PEs and the lack of MBE. The zero-polar-field condition in the south started only around 2013, but it ended by June 2014. Thus the asymmetry in the times of polarity reversal switched between cycle 23 and 24. The polar MBE is a good proxy for the polar magnetic field strength as indicated by the high degree of correlation between the two. The cross-correlation between the high- and low-latitude MBEs is significant for a lag of approximately 5.5 to 7.3 years, suggesting that the polar field of one cycle indicates the sunspot number of the next cycle in agreement with the Babcock-Leighton mechanism of solar cycles. The extended period of near-zero field in the north-polar region should result in a weak and delayed sunspot activity in the northern hemisphere in cycle 25.

  3. Disturbance observer based current controller for vector controlled IM drives

    DEFF Research Database (Denmark)

    Teodorescu, Remus; Dal, Mehmet

    induction motor (IM) drives. The control design, based on synchronously rotating d-q frame model of the machine, has a simple structure that combines the proportional portion of a conventional PI control and output of the observer. The observer is predicted to estimate the disturbances caused by parameters......In order to increase the accuracy of the current control loop, usually, well known parameter compensation and/or cross decoupling techniques are employed for advanced ac drives. In this paper, instead of using these techniques an observer-based current controller is proposed for vector controlled...... change in current control loop and, also to remove undesired cross coupling existing between components of the stator current. The observer uses the measured stator currents and estimated PWM voltages, and produces a disturbance signal with a low pass filter. The proposed control scheme reduces cross...

  4. Global Observer-based Attitude Controller Using Direct Inertial Measurements

    Directory of Open Access Journals (Sweden)

    Saâdi Bouhired

    2014-04-01

    Full Text Available In this work, we address the problem of global attitude control using direct inertial measurements. When using direct inertial measurement to observe the rigid body attitude, it is shown that due to a geometrical obstruction, it is impossible to achieve global asymptotic stability. In fact, for a particular initial condition the tracking error quaternion converges to a pure imaginary quaternion formed by an eigenvector of a characteristic matrix related to the inertial constant and known vectors. Our proposition consists of adding a dynamic signal to force the rigid body to escape from such a situation. The proposed observer-based controller is synthesized based on a single Lyapunov function and a stability analysis shows that the controller stabilizes globally and asymptotically the rigid body attitude at the desired one. The effectiveness of the proposed observer-based controller is confirmed by simulation results.

  5. Calculating Track-Based Observables for the LHC

    OpenAIRE

    Chang, Hsi-Ming(Department of Physics, University of California at San Diego, La Jolla, CA 92093, USA); Procura, Massimiliano; Thaler, Jesse; Waalewijn, Wouter J.

    2013-01-01

    By using observables that only depend on charged particles (tracks), one can efficiently suppress pile-up contamination at the LHC. Such measurements are not infrared safe in perturbation theory, so any calculation of track-based observables must account for hadronization effects. We develop a formalism to perform these calculations in QCD, by matching partonic cross sections onto new non-perturbative objects called track functions which absorb infrared divergences. The track function T_i(x) ...

  6. Management of rheumatic chorea: an observational study

    Directory of Open Access Journals (Sweden)

    Araújo Alexandra Prufer de Queiroz Campos

    2002-01-01

    Full Text Available BACKGROUND: Rheumatic chorea (RC has recently been linked to an antibody-mediated immune mechanism. OBJECTIVE/METHOD: To verify if this knowledge reflected in management changes we conceived a descriptive study. RESULTS: The medical charts of 20 children (13 females aged 6 to 12 years (mean 8 years, diagnosed as RC from June 1996 to June 1999, were reviewed. All patients received some medical treatment. Haloperidol was the most prescribed medication (15 patients - 75 %. Sulpiride, diazepam and valproate were also used as symptomatic treatment. Imune-modulating therapy with prednisone was prescribed for seven children. The shortest course of chorea (16 days occurred in a patient treated with prednisone. CONCLUSION: Prednisone has been prescribed for rheumatic chorea besides the traditional symptomatic approach. A great variety of antichoreic drugs are being employed.

  7. Observational study of children with aerophagia.

    Science.gov (United States)

    Loening-Baucke, Vera; Swidsinski, Alexander

    2008-09-01

    Aerophagia is a rare disorder in children. The diagnosis is often delayed, especially when it occurs concomitantly with constipation. The aim of this report is to increase awareness about aerophagia. This study describes 2 girls and 7 boys, 2 to 10.4 years of age, with functional constipation and gaseous abdominal distention. The abdomen was visibly distended, nontender, and tympanitic in all. Documenting less distention on awakening helped to make the diagnosis. Air swallowing, belching, and flatulence were infrequently reported. The rectal examination often revealed a dilated rectal ampulla filled with gas or stool and gas. The abdominal X-ray showed gaseous distention of the colon in all and of the stomach and small bowel in 8 children. Treatment consisted of educating parents and children about air sucking and swallowing, encouraging the children to stop the excessive air swallowing, and suggesting to them not to use drinking straws and not to drink carbonated beverages. The aerophagia resolved in all in 2 to 20 months (mean=8 months). PMID:18445758

  8. The relationship between observer-based toxicity scoring and patient assessed symptom severity after treatment for head and neck cancer. A correlative cross sectional study of the DAHANCA toxicity scoring system and the EORTC quality of life questionnaires

    International Nuclear Information System (INIS)

    Background and purpose: Morbidity is an important issue in cancer research. The observer-based toxicity scoring system used by DAHANCA (the Danish head and neck cancer study group) has proved itself sensitive to differences in toxicity in a large randomised study, but like other toxicity scoring systems it has not been formally validated. Conversely, the EORTC quality of life questionnaire (QLQ) has been validated as a tool for collecting information about the consequences of disease and treatment on the well being of cancer patients. The purpose of this study was to examine the relationship between the two methods of side effect recording. Patients and methods: One hundred and sixteen recurrence free patients with laryngeal (n=44), pharyngeal (n=34) and oral cavity (n=38) cancer attending follow-up after radiotherapy (n=83) or surgery (n=33) completed EORTC C30, the core questionnaire concerning general symptoms and function and EORTC H and N35 the head and neck specific questionnaire. The attending physicians in the follow-up clinic evaluated and recorded DAHANCA toxicity scores on the same patients. Results: The DAHANCA toxicity scoring system and the EORTC QLQ correlated with several clinical endpoints. The conceptually similar endpoints of the two methods correlated significantly. The objective endpoints of the DAHANCA scoring system were only correlated with quality of life endpoints to a very low degree. The DAHANCA toxicity scores had a low sensitivity (0.48-0.74) in detecting equivalent subjective complaints from the questionnaires and the observer-based scoring system severely underestimated patient complaints. A specific patient group where the DAHANCA score had a higher tendency to fail could not be detected. Conclusion: The DAHANCA toxicity score is an effective instrument in assessing objective treatment induced toxicity in head and neck cancer patients but insensitive and non-specific with regard to patient assessed subjective endpoints. This

  9. Observer-based Hamiltonian identification for quantum systems

    OpenAIRE

    Mirrahimi, Mazyar; Rouchon, Pierre

    2007-01-01

    An observer-based Hamiltonian identification algorithm for quantum systems is proposed. For the 2-level case an exponential convergence result based on averaging arguments and some relevant transformations is provided. The convergence for multi-level cases is discussed using some heuristic arguments and the relevance of the method is tested via simulations. Finally, the robustness issue with respect to non-negligible uncertainties and experimental noises is also addressed on simulations.

  10. Ozone distributions over southern Lake Michigan: comparisons between ferry-based observations, shoreline-based DOAS observations and model forecasts

    Science.gov (United States)

    Cleary, P. A.; Fuhrman, N.; Schulz, L.; Schafer, J.; Fillingham, J.; Bootsma, H.; McQueen, J.; Tang, Y.; Langel, T.; McKeen, S.; Williams, E. J.; Brown, S. S.

    2015-05-01

    Air quality forecast models typically predict large summertime ozone abundances over water relative to land in the Great Lakes region. While each state bordering Lake Michigan has dedicated monitoring systems, offshore measurements have been sparse, mainly executed through specific short-term campaigns. This study examines ozone abundances over Lake Michigan as measured on the Lake Express ferry, by shoreline differential optical absorption spectroscopy (DOAS) observations in southeastern Wisconsin and as predicted by the Community Multiscale Air Quality (CMAQ) model. From 2008 to 2009 measurements of O3, SO2, NO2 and formaldehyde were made in the summertime by DOAS at a shoreline site in Kenosha, WI. From 2008 to 2010 measurements of ambient ozone were conducted on the Lake Express, a high-speed ferry that travels between Milwaukee, WI, and Muskegon, MI, up to six times daily from spring to fall. Ferry ozone observations over Lake Michigan were an average of 3.8 ppb higher than those measured at shoreline in Kenosha, with little dependence on position of the ferry or temperature and with greatest differences during evening and night. Concurrent 1-48 h forecasts from the CMAQ model in the upper Midwestern region surrounding Lake Michigan were compared to ferry ozone measurements, shoreline DOAS measurements and Environmental Protection Agency (EPA) station measurements. The bias of the model O3 forecast was computed and evaluated with respect to ferry-based measurements. Trends in the bias with respect to location and time of day were explored showing non-uniformity in model bias over the lake. Model ozone bias was consistently high over the lake in comparison to land-based measurements, with highest biases for 25-48 h after initialization.

  11. Gain Scheduling of Observer-Based Controllers with Integral Action

    DEFF Research Database (Denmark)

    Trangbæk, Klaus; Stoustrup, Jakob; Bendtsen, Jan Dimon

    2006-01-01

     This paper presents a method for continuous gain scheduling of  observer-based controllers with integral action. Given two stabilising controllers for a given system, explicit state space formulae are presented, allowing to change gradually from one  controller to the other while preserving...

  12. Challenges and Rewards in Ground-Based Observing

    Science.gov (United States)

    Reardon, Kevin P.

    2016-05-01

    DKIST will be largest ground-based project in solar physics, and will offer access and data to the whole community. In pursuit of exciting science, many users may have their first encounters with high-resolution, ground-based solar observations. New facilities, space or ground-based, all bring particular signatures in their data. While tools or processed datasets might serve to minimize such non-solar signatures, it is nonetheless important for users to understand the impacts on observation planning, the nature of the corrections applied, and any residual effects on their data.In this talk I will review some of the instrumental and atmospheric signatures that are important for ground-based observing, in particular in planning for the potential capabilities of the DKIST Data Center. These techniques include image warping, local PSF deconvolution, atmospheric dispersion correction, and scattered light removal. I will present examples of data sets afflicted by such problems as well as some of the algorithms used in characterizing and removing these contributions. This will demonstrate how even with the challenges of observing through a turbulent atmosphere, it is possible to achieve dramatic scientific results.

  13. A cooperative control algorithm for camera based observational systems.

    Energy Technology Data Exchange (ETDEWEB)

    Young, Joseph G.

    2012-01-01

    Over the last several years, there has been considerable growth in camera based observation systems for a variety of safety, scientific, and recreational applications. In order to improve the effectiveness of these systems, we frequently desire the ability to increase the number of observed objects, but solving this problem is not as simple as adding more cameras. Quite often, there are economic or physical restrictions that prevent us from adding additional cameras to the system. As a result, we require methods that coordinate the tracking of objects between multiple cameras in an optimal way. In order to accomplish this goal, we present a new cooperative control algorithm for a camera based observational system. Specifically, we present a receding horizon control where we model the underlying optimal control problem as a mixed integer linear program. The benefit of this design is that we can coordinate the actions between each camera while simultaneously respecting its kinematics. In addition, we further improve the quality of our solution by coupling our algorithm with a Kalman filter. Through this integration, we not only add a predictive component to our control, but we use the uncertainty estimates provided by the filter to encourage the system to periodically observe any outliers in the observed area. This combined approach allows us to intelligently observe the entire region of interest in an effective and thorough manner.

  14. Lunar-based Earth observation geometrical characteristics research

    Science.gov (United States)

    Ren, Yuanzhen; Liu, Guang; Ye, Hanlin; Guo, Huadong; Ding, Yixing; Chen, Zhaoning

    2016-07-01

    As is known to all, there are various platforms for carrying sensors to observe Earth, such as automobiles, aircrafts and satellites. Nowadays, we focus on a new platform, Moon, because of its longevity, stability and vast space. These advantages make it to be the next potential platform for observing Earth, enabling us to get the consistent and global measurements. In order to get a better understanding of lunar-based Earth observation, we discuss its geometrical characteristics. At present, there are no sensors on the Moon for observing Earth and we are not able to obtain a series of real experiment data. As a result, theoretical modeling and numerical calculation are used in this paper. At first, we construct an approximate geometrical model of lunar-based Earth observation, which assumes that Earth and Moon are spheres. Next, we calculate the position of Sun, Earth and Moon based on the JPL ephemeris. With the help of positions data and geometrical model, it is possible for us to decide the location of terminator and substellar points. However, in order to determine their precise position in the conventional terrestrial coordinate system, reference frames transformations are introduced as well. Besides, taking advantages of the relative positions of Sun, Earth and Moon, we get the total coverage of lunar-based Earth optical observation. Furthermore, we calculate a more precise coverage, considering placing sensors on different positions of Moon, which is influenced by its attitude parameters. In addition, different ephemeris data are compared in our research and little difference is found.

  15. Velocity observer-based iterative learning control for robot manipulators

    Science.gov (United States)

    Bouakrif, Farah; Boukhetala, Djamel; Boudjema, Farès

    2013-02-01

    This article addresses the problem of designing an iterative learning control for trajectory tracking of rigid robot manipulators subject to external disturbances, and performing repetitive tasks, without using the velocity measurement. For solving this problem, a velocity observer having an iterative form is proposed to reconstruct the velocity signal in the control laws. Under assumptions that the disturbances are repetitive and the velocities are bounded, it has been shown that the whole control system (robot plus controller plus observer) is asymptotically stable and the observation error is globally asymptotically stable, over the whole finite time-interval when the iteration number tends to infinity. This proof is based upon the use of a Lyapunov-like positive definite sequence, which is shown to be monotonically decreasing under the proposed observer-controller schemes.

  16. Adaptive Observer-Based Fault Estimate for Nonlinear Systems

    Institute of Scientific and Technical Information of China (English)

    ZONG Qun; LIU Wenjing; LIU Li

    2006-01-01

    An approach for adaptive observer-based fault estimate for nonlinear system is proposed.H-infinity theory is applied to analyzing the design method and stable conditions of the adaptive observer,from which both system state and fault can be estimated.It is proved that the fault estimate error is related to the given H-infinity track performance indexes,as well as to the changing rate of the fault and the Lipschitz constant of the nonlinear item.The design steps of the adaptive observer are proposed.The simulation results show that the observer has good performance for fault estimate even when the system includes nonlinear terms,which confirms the effectiveness of the method.

  17. Parameterization of oceanic whitecap fraction based on satellite observations

    Directory of Open Access Journals (Sweden)

    M. F. M. A. Albert

    2015-08-01

    Full Text Available In this study the utility of satellite-based whitecap fraction (W values for the prediction of sea spray aerosol (SSA emission rates is explored. More specifically, the study is aimed at improving the accuracy of the sea spray source function (SSSF derived by using the whitecap method through the reduction of the uncertainties in the parameterization of W by better accounting for its natural variability. The starting point is a dataset containing W data, together with matching environmental and statistical data, for 2006. Whitecap fraction W was estimated from observations of the ocean surface brightness temperature TB by satellite-borne radiometers at two frequencies (10 and 37 GHz. A global scale assessment of the data set to evaluate the wind speed dependence of W revealed a quadratic correlation between W and U10, as well as a relatively larger spread in the 37 GHz data set. The latter could be attributed to secondary factors affecting W in addition to U10. To better visualize these secondary factors, a regional scale assessment over different seasons was performed. This assessment indicates that the influence of secondary factors on W is for the largest part imbedded in the exponent of the wind speed dependence. Hence no further improvement can be expected by looking at effects of other factors on the variation in W explicitly. From the regional analysis, a new globally applicable quadratic W(U10 parameterization was derived. An intrinsic correlation between W and U10 that could have been introduced while estimating W from TB was determined, evaluated and presumed to lie within the error margins of the newly derived W(U10 parameterization. The satellite-based parameterization was compared to parameterizations from other studies and was applied in a SSSF to estimate the global SSA emission rate. The thus obtained SSA production for 2006 of 4.1 × 1012 kg is within previously reported estimates. While recent studies that account for

  18. Observational studies of X-ray binary systems

    International Nuclear Information System (INIS)

    The subject of Chapter 1 is theoretical. The other chapters, Ch. 2 to 6, contain original observational data and efforts towards their interpretation. Of these, Ch. 3, 4 and 5 deal with massive X-ray binaries, Ch. 6 with low-mass systems and Ch. 2 with Cygnus X-3, which we have not yet been able to assign to any of these two classes. The X-ray observations described were made with the COS-B satellite. Work based on UV and optical observations is described in Ch. 5. The UV observations were made with the IUE satellite, the optical observations at several ground-based observatories. (Auth.)

  19. Cloud detection and classification based on MAX-DOAS observations

    OpenAIRE

    Wagner, T; A. Apituley; Beirle, S.; S. Dörner; Friess, U.; J. Remmers; R. Shaiganfar

    2014-01-01

    Multi-axis differential optical absorption spectroscopy (MAX-DOAS) observations of aerosols and trace gases can be strongly influenced by clouds. Thus, it is important to identify clouds and characterise their properties. In this study we investigate the effects of clouds on several quantities which can be derived from MAX-DOAS observations, like radiance, the colour index (radiance ratio at two selected wavelengths), the absorption of the oxygen dimer O4 and the fraction of in...

  20. Underwater navigation using diffusion-based trajectory observers

    DEFF Research Database (Denmark)

    Jouffroy, Jerome; Opderbecke, Jan

    2007-01-01

    This paper addresses the issue of estimating underwater vehicle trajectories using gyro-Doppler (body-fixed velocities) and acoustic positioning signals (earth-fixed positions). The approach consists of diffusion-based observers processing a whole trajectory segment at a time, allowing the...... consideration of important practical problems such as different information update rates, outages, and outliers in a very simple framework. Results of contraction theory are used to prove that the observers are convergent, i.e., stable in the incremental sense. Simulation and experimental results are presented...

  1. Virtual Estimator for Piecewise Linear Systems Based on Observability Analysis

    Science.gov (United States)

    Morales-Morales, Cornelio; Adam-Medina, Manuel; Cervantes, Ilse; Vela-Valdés and, Luis G.; García Beltrán, Carlos Daniel

    2013-01-01

    This article proposes a virtual sensor for piecewise linear systems based on observability analysis that is in function of a commutation law related with the system's outpu. This virtual sensor is also known as a state estimator. Besides, it presents a detector of active mode when the commutation sequences of each linear subsystem are arbitrary and unknown. For the previous, this article proposes a set of virtual estimators that discern the commutation paths of the system and allow estimating their output. In this work a methodology in order to test the observability for piecewise linear systems with discrete time is proposed. An academic example is presented to show the obtained results. PMID:23447007

  2. Exact, almost and delayed fault detection: An observer based approach

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Saberi, Ali; Stoorvogel, Anton A.;

    1999-01-01

    This paper consider the problem of fault detection and isolation in continuous- and discrete-time systems while using zero or almost zero threshold. A number of different fault detections and isolation problems using exact or almost exact disturbance decoupling are formulated. Solvability...... conditions are given for the formulated design problems together with methods for appropriate design of observer based fault detectors. The l-step delayed fault detection problem is also considered for discrete-time systems . Moreover, certain indirect fault detection methods such as unknown input observers...

  3. Verifying Embedded Systems using Component-based Runtime Observers

    DEFF Research Database (Denmark)

    Guan, Wei; Marian, Nicolae; Angelov, Christo K.

    Formal verification methods, such as exhaustive model checking, are often infeasible because of high computational complexity. Runtime observers (monitors) provide an alternative, light-weight verification method, which offers a non-exhaustive yet feasible approach to monitoring system behavior...... against formally specified properties. This paper presents a component-based design method for runtime observers, which are configured from instances of prefabricated reusable components---Predicate Evaluator (PE) and Temporal Evaluator (TE). The PE computes atomic propositions for the TE; the latter is a...

  4. Observer-Based Fuel Control Using Oxygen Measurement

    DEFF Research Database (Denmark)

    Andersen, Palle; Bendtsen, Jan Dimon; Mortensen, Jan Henrik;

    This report describes an attempt to improve the existing control af coal mills used at the Danish power plant Nordjyllandsværket Unit 3. The coal mills are not equipped with coal flow sensors; thus an observer-based approach is investigated. A nonlinear differential equation model of the boiler is...... constructed and validated against data obtained at the plant. A Kalman filter based on measurements of combustion air flow led into the furnace and oxygen concentration in the flue gas is designed to estimate the actual coal flow. With this estimate, it becomes possible to close an inner loop around the coal...

  5. Observer Based Detection of Sensor Faults in Wind Turbines

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob; Nielsen, R.;

    2009-01-01

    An observer based scheme is proposed to detect sensor faults in wind  turbines. In the example used for the proposed scheme the wind turbine  drive train is considered. A model of the drive train is used to  design the observer, and in this model the wind speed is an important  input, however, if...... an unknown input observer the fault detection  scheme can be non dependent on the actual wind speed. The scheme  is validated on data from a more advanced and detailed simulation  model. The proposed scheme detects the sensor faults a few samples  after the beginning of the faults....

  6. Detecting influential observations in a model-based cluster analysis

    OpenAIRE

    Bruckers, L.; Molenberghs, G; Verbeke, G; Geys, H.

    2016-01-01

    Finite mixture models have been used to model population heterogeneity and to relax distributional assumptions. These models are also convenient tools for clustering and classification of complex data such as, for example, repeated-measurements data. The performance of model-based clustering algorithms is sensitive to influential and outlying observations. Methods for identifying outliers in a finite mixture model have been described in the literature. Approaches to identify influential obser...

  7. Chaotic Observer-based Synchronization Under Information Constraints

    OpenAIRE

    Fradkov, Alexander L.; Andrievsky, Boris; Evans, Robin J.

    2005-01-01

    Limit possibilities of observer-based synchronization systems under information constraints (limited information capacity of the coupling channel) are evaluated. We give theoretical analysis for multi-dimensional drive-response systems represented in the Lurie form (linear part plus nonlinearity depending only on measurable outputs). It is shown that the upper bound of the limit synchronization error (LSE) is proportional to the upper bound of the transmission error. As a consequence, the upp...

  8. An observational study of sea breeze characteristics over Kalpakkam Coast

    International Nuclear Information System (INIS)

    An observational study of the sea breeze characteristics has been carried out at Kalpakkam, India which lies on the East coast of Southern Indian peninsula about 700 m inland from the sea, the Bay of Bengal. There are clear and significant changes in the surface meteorological parameters at the onset and during sea-breeze phenomenon in the coastal areas. Hourly averaged measurements from a 30 m tall micrometeorological tower were used to study the sea-breeze characteristics at the above site. In this study, based on detailed analysis of the data on-set criteria of the sea breeze is characterized by increase in relative humidity at least by 5%, fall in temperature by equal or greater than 0.5 K and increase in wind speed with respect to previous hour record. The present study is also compared with the earlier studies in relation to sea breeze carried out at Chennai located approximately 80 km North from Kalpakkam and the differences between these studies are discussed. The comparison of sea breeze characteristics of the present study with those from earlier studies that were carried out more than half a century back also reflects the changes due to urbanization and other development activities as well as resulting climatic impacts. (author)

  9. Sounding stellar cycles with Kepler - II. Ground-based observations

    CERN Document Server

    Karoff, C; Chaplin, W J; Frandsen, S; Grundahl, F; Kjeldsen, H; Christensen-Dalsgaard, J; Nielsen, M B; Frimann, S; Thygesen, A O; Arentoft, T; Amby, T M; Sousa, S G; Buzasi, D L

    2013-01-01

    We have monitored 20 Sun-like stars in the Kepler field-of-view for excess flux with the FIES spectrograph on the Nordic Optical Telescope since the launch of Kepler spacecraft in 2009. These 20 stars were selected based on their asteroseismic properties to sample the parameter space (effective temperature, surface gravity, activity level etc.) around the Sun. Though the ultimate goal is to improve stellar dynamo models, we focus the present paper on the combination of space-based and ground-based observations can be used to test the age-rotation-activity relations. In this paper we describe the considerations behind the selection of these 20 Sun-like stars and present an initial asteroseismic analysis, which includes stellar age estimates. We also describe the observations from the Nordic Optical Telescope and present mean values of measured excess fluxes. These measurements are combined with estimates of the rotation periods obtained from a simple analysis of the modulation in photometric observations from ...

  10. Effectiveness of a multidisciplinary critical pathway based on a computerised physician order entry system for ST-segment elevation myocardial infarction management in the emergency department: a retrospective observational study

    Science.gov (United States)

    Park, Yoo Seok; Chung, Sung Phil; You, Je Sung; Kim, Min Joung; Chung, Hyun Soo; Hong, Jung Hwa; Lee, Hye Sun; Wang, Jinwon; Park, Incheol

    2016-01-01

    Objectives The purpose of this study was to investigate whether a multidisciplinary organised critical pathway (CP) for ST-segment elevation myocardial infarction (STEMI) management can significantly attenuate differences in the duration from emergency department (ED) arrival to evaluation and treatment, regardless of the arrival time, by eliminating off-hour and weekend effects. Design Retrospective observational cohort study. Setting 2 tertiary academic hospitals. Participants Consecutive patients in the Fast Interrogation Rule for STEMI (FIRST) program. Interventions A study was conducted on patients in the FIRST program, which uses a computerised physician order entry (CPOE) system. The patient demographics, time intervals and clinical outcomes were analysed based on the arrival time at the ED: group 1, normal working hours on weekdays; group 2, off-hours on weekdays; group 3, normal working hours on weekends; and group 4, off-hours on weekends. Primary and secondary outcome measures Clinical outcomes categorised according to 30-day mortality, in-hospital mortality and the length of stay. Results The duration from door-to-data or FIRST activation did not differ significantly among the 4 groups. The median duration between arrival and balloon placement during percutaneous coronary intervention did not significantly exceed 90 min, and the proportions (89.6–95.1%) of patients with door-to-balloon times within 90 min did not significantly differ among the 4 groups, regardless of the ED arrival time (p=0.147). Moreover, no differences in the 30-day (p=0.8173) and in-hospital mortality (p=0.9107) were observed in patients with STEMI. Conclusions A multidisciplinary CP for STEMI based on a CPOE system can effectively decrease disparities in the door-to-data duration and proportions of patients with door-to-balloon times within 90 min, regardless of the ED arrival time. The application of a multidisciplinary CP may also help attenuate off-hour and weekend

  11. Spatial mapping of ground-based observations of total ozone

    Science.gov (United States)

    Chang, K.-L.; Guillas, S.; Fioletov, V. E.

    2015-10-01

    Total column ozone variations estimated using ground-based stations provide important independent source of information in addition to satellite-based estimates. This estimation has been vigorously challenged by data inhomogeneity in time and by the irregularity of the spatial distribution of stations, as well as by interruptions in observation records. Furthermore, some stations have calibration issues and thus observations may drift. In this paper we compare the spatial interpolation of ozone levels using the novel stochastic partial differential equation (SPDE) approach with the covariance-based kriging. We show how these new spatial predictions are more accurate, less uncertain and more robust. We construct long-term zonal means to investigate the robustness against the absence of measurements at some stations as well as instruments drifts. We conclude that time series analyzes can benefit from the SPDE approach compared to the covariance-based kriging when stations are missing, but the positive impact of the technique is less pronounced in the case of drifts.

  12. Kalman Based Finite State Controller for Partially Observable Domains

    Directory of Open Access Journals (Sweden)

    H. Levent Akin

    2008-11-01

    Full Text Available A real world environment is often partially observable by the agents either because of noisy sensors or incomplete perception. Moreover, it has continuous state space in nature, and agents must decide on an action for each point in internal continuous belief space. Consequently, it is convenient to model this type of decisionmaking problems as Partially Observable Markov Decision Processes (POMDPs with continuous observation and state space. Most of the POMDP methods whether approximate or exact assume that the underlying world dynamics or POMDP parameters such as transition and observation probabilities are known. However, for many real world environments it is very difficult if not impossible to obtain such information. We assume that only the internal dynamics of the agent, such as the actuator noise, interpretation of the sensor suite, are known. Using these internal dynamics, our algorithm, namely Kalman Based Finite State Controller (KBFSC, constructs an internal world model over the continuous belief space, represented by a finite state automaton. Constructed automaton nodes are points of the continuous belief space sharing a common best action and a common uncertainty level. KBFSC deals with continuous Gaussian-based POMDPs. It makes use of Kalman Filter for belief state estimation, which also is an efficient method to prune unvisited segments of the belief space and can foresee the reachable belief points approximately calculating the horizon N policy. KBFSC does not use an "explore and update" approach in the value calculation as TD-learning. Therefore KBFSC does not have an extensive exploration-exploitation phase. Using the MDP case reward and the internal dynamics of the agent, KBFSC can automatically construct the finite state automaton (FSA representing the approximate optimal policy without the need for discretization of the state and observation space. Moreover, the policy always converges for POMDP problems.

  13. RADIOLOGICAL PATTERN OF LUNG CANCER – A PROSPECTIVE OBSERVATIONAL STUDY

    Directory of Open Access Journals (Sweden)

    Allena Prem

    2015-10-01

    Full Text Available This was performed to observe various radiological presentations of lung cancer at the initial evaluation and to elicit correlation to histopathological diagnosis in all patients to a tertiary chest care hospital. AIM: To study various radiological presentations among lung cancer patients Method: we included all the patients with lung cancer reviewed during a 12mth period between March 2012 to November 2014 who had a definite tissue diagnosis and whose staging based on CT thorax were available. RESULTS: 65 patients were evaluated. Right sided lesions predominated with 60% and on left side being 40%. On either side put together, upper lobe 46.15% & middle lobe 36.9% and lower lobe 16.9%.Based on location of tumor 26% of the lesions are peripherally located, 24.5% are central localization, 13.8% are located intermedially. Radiological pattern of presentation: 67% of the cases presented as mass lesions, 9% as obstructive pneumonitis and 23% as combined mass with collapse and 23.07% as pleural effusion. Histological pattern of presentation: squamous cell carcinoma is most common type with 49.23%, adeno 33%, small cell 15%, others 1.5% Most of the cases presented to the hospital in stage IV with 56.36% and stage IIIA 16.36% and stage IIIB as 18.18%. CONCLUSION: we observed most of the lung cancers presented as mass lesion with peripherally located tumor and the most common histological type is squamous cell carcinoma, presented at advanced stages.

  14. How safe do teenagers behave on Facebook? An observational study.

    Directory of Open Access Journals (Sweden)

    Ellen Vanderhoven

    Full Text Available The substantial use of social network sites by teenagers has raised concerns about privacy and security. Previous research about behavior on social network sites was mostly based on surveys and interviews. Observational research overcomes problems inherent to this research method, for example social desirability. However, existing observational research mostly focuses on public profiles of young adults. Therefore, the current observation-study includes 1050 public and non-public Facebook-profiles of teenagers (13-18 to investigate (1 what kind of information teenagers post on their profile, (2 to what extent they protect this information using privacy-settings and (3 how much risky information they have on their profile. It was found that young people mostly post pictures, interests and some basic personal information on their profile. Some of them manage their privacy-settings as such that this information is reserved for friends' eyes only, but a lot of information is accessible on the friends-of-friends' pages. Although general risk scores are rather low, more detailed analyses show that teenagers nevertheless post a significant amount of risky information. Moreover, older teenagers and girls post more (risky information while there are no differences in applying privacy settings. We found no differences in the Facebook behavior of teenagers enrolled in different education forms. Implications of these results are discussed.

  15. Wind wave characteristics based on visual Observations and satellite altimetry

    Science.gov (United States)

    Grigorieva, V. G.; Badulin, S. I.

    2016-01-01

    Joint analysis of wind wave characteristics derived from the Voluntary Observing Ship data (VOS) and satellite altimetry is presented as the first step of the synthesis of different data sources. Global distributions of significant wave heights and periods along with wind speed are constructed using various techniques and empirical parameterizations. Good qualitative and quantitative agreement of VOS and satellite altimetry is found especially for regions with high spatio-temporal density of observations. The problems and prospects of the further development of the study are discussed in the context of global wave climatology and marine safety.

  16. Mooring System of Ocean Turbulence Observation Based on Submerged Buoy

    Institute of Scientific and Technical Information of China (English)

    SONG Da-lei; SUN Jing-jing; XUE Bing; JIANG Qian-li; WU Bing-wei

    2013-01-01

    A comparison experiment has been taken in the Kiaochow Bay between a newly designed mooring turbulence observation instrument (MTOI) and microstructure profiler MSS60 made by Sea & Sun.The whole observing system is based on a submerged buoy,in which the turbulence observation instrument is embedded,with a streamline-shape floating body,which is made of buoyancy material of glass microsphere.For the movement of seawater and the cable shaking strongly anytime influence the behaviors of the floating body,the accelerate sensors are used for the vibration measurement in the instrument together with the shear probe sensor.Both the vibration data and the shear data are acquired by the instrument at the same time.During data processing,the vibration signals can be removed and leave the shear data which we really need.In order to prove the reliability of the new turbulence instrument MTOI,a comparison experiment was designed.The measuring conditions are the same both in time and space.By this way,the two groups of data are comparable.In this paper,the conclusion gives a good similarity of 0.93 for the two groups of shear data in dissipation rate.The processing of the data acquired by MTOI is based on the cross-spectrum analysis,and the dissipation rate of it matches the Nasmyth spectrum well.

  17. Longitudinal tire force estimation based on sliding mode observer

    Energy Technology Data Exchange (ETDEWEB)

    El Hadri, A.; Cadiou, J.C.; M' Sirdi, N.K. [Versailles Univ., Paris (France). Lab. de Robotique; Beurier, G.; Delanne, Y. [Lab. Central des Ponts, Centre de Nantes (France)

    2001-07-01

    This paper presents an estimation method for vehicle longitudinal dynamics, particularly the tractive/braking force. The estimation can be used to detect a critical driving situation to improve security. It can be used also in several vehicle control systems. The main characteristics of the vehicle longitudinal dynamics were taken into account in the model used to design an observer and computer simulations. The state variables are the angular wheel velocity, vehicle velocity and the longitudinal tire force. The proposed differential equation of the tractive/braking force is derived using the concept of relaxation length. The observer designed is based on the sliding mode approach using only the angular wheel velocity measurement. The proposed method of estimation is verified through a one-wheel simulation model with a ''Magic formula'' tire model. Simulations results show an excellent reconstruction of the tire force. (orig.)

  18. An observational study of driver distraction in England.

    OpenAIRE

    Sullman, Mark J. M.

    2012-01-01

    This study set out to investigate the proportion of UK drivers who engage in some form of distracting behaviour whilst driving. Data were collected by roadside observation in six urban centres in the South of England. The observations took place on randomly selected roads at three different time periods during two consecutive Tuesdays. The data revealed that 14.4% of the 7168 drivers observed were found to be engaged in a distracting activity. The most frequently observed distraction was talk...

  19. Influence of treatment with alendronate on the speed of sound, an ultrasound parameter, of the calcaneus in postmenopausal Japanese women with osteoporosis: a clinical practice-based observational study

    Directory of Open Access Journals (Sweden)

    Iwamoto J

    2012-06-01

    Full Text Available Jun Iwamoto,1 Tetsuya Takada,2 Yoshihiro Sato,3 Hideo Matsumoto11Institute for Integrated Sports Medicine, Keio University School of Medicine, Tokyo, 2Department of Internal Medicine, Hiyoshi Medical Clinic, Kanagawa, 3Department of Neurology, Mitate Hospital, Fukuoka, JapanPurpose: The influence of alendronate (ALN treatment on the quantitative ultrasound parameters of the calcaneus remains to be established in Japanese patients. The aim of the present clinical practice-based observational study was to examine the influence of ALN treatment for 1 year on the speed of sound (SOS of the calcaneus and bone turnover markers in postmenopausal Japanese women with osteoporosis.Patients and methods: Forty-five postmenopausal Japanese women with osteoporosis who had received treatment with ALN for more than 1 year were enrolled in the study. The SOS and bone turnover markers were monitored over 1 year of ALN treatment.Results: The urinary levels of cross-linked N-terminal telopeptides of type I collagen and serum levels of alkaline phosphatase decreased significantly from the baseline values (–44.9% at 3 months and –22.2% at 12 months, respectively. The SOS increased modestly, but significantly, from the baseline value (0.6% at both 6 and 12 months. The percentage decrease in the urinary levels of cross-linked N-terminal telopeptides of type I collagen at 3 months was significantly correlated with the percentage increase in the SOS only at 6 months (correlation coefficient, 0.299.Conclusion: The present study confirmed that ALN treatment suppressed bone turnover, producing a clinically significant increase in the SOS of the calcaneus in postmenopausal Japanese women with osteoporosis.Keywords: postmenopausal osteoporosis, quantitative ultrasound (QUS, SOS, bone turnover, biochemical markers

  20. Satellite-based Observation of Arctic River Dynamics

    Science.gov (United States)

    Overeem, I.; Brakenridge, R.; Hudson, B.

    2015-12-01

    One of the indicators of a warming Arctic region is an intensification of the hydrological cycle, with increasing permafrost and glacial melt and possibly more precipitation resulting in higher river runoff. Indeed, a significant increase of nearly 10% in annual river flux has been observed in 13 major rivers throughout the entire Arctic region over the last 30 years. However, direct measurements are extremely sparse for 100's of smaller-scale tundra river systems, as well as for proglacial rivers around the Greenland Ice Sheet margin. Observations at in-situ gauging stations are hampered by seasonal ice coverage, break-up and freeze-up dynamics, unstable banks, and difficult access. To overcome such difficulties, we develop remote-sensing based river discharge measurement techniques using a variety of satellite sensors, including reflectance in the near-infrared band of MODIS, LANDSAT, and brightness temperature from the passive microwave sensors AMSR-E and AMSR-2. We use varying inundation of the river channel and floodplain throughout a season to quantify the changing Arctic river flux. A new approach to detect river ice break up in spring has been developed, and is now undergoing validation. To calibrate the remote sensing signal to daily river discharge, we employ either in-situ short observation records, or a numerical distributed hydrological model driven by daily reanalysis climate data. Quantitative reconstructions of meltwater fluxes in rivers along the Greenland Ice Sheet margin obtained so far show a dampened response of these rivers to Greenland Ice Sheet melt. Techniques are now deployed to map river dynamics along the Chukchi Sea and Beaufort Sea coasts, and show shifts in break-up dynamics and flooding patterns. Once calibrated, satellite-based reconstructions have the potential to lengthen short observational records to a ~15 year timespan.

  1. An Observational Study of Entrainment Rate in Deep Convection

    Directory of Open Access Journals (Sweden)

    Xiaohao Guo

    2015-09-01

    Full Text Available This study estimates entrainment rate and investigates its relationships with cloud properties in 156 deep convective clouds based on in-situ aircraft observations during the TOGA-COARE (Tropical Ocean Global Atmosphere Coupled Ocean Atmosphere Response Experiment field campaign over the western Pacific. To the authors’ knowledge, this is the first study on the probability density function of entrainment rate, the relationships between entrainment rate and cloud microphysics, and the effects of dry air sources on the calculated entrainment rate in deep convection from an observational perspective. Results show that the probability density function of entrainment rate can be well fitted by lognormal, gamma or Weibull distribution, with coefficients of determination being 0.82, 0.85 and 0.80, respectively. Entrainment tends to reduce temperature, water vapor content and moist static energy in cloud due to evaporative cooling and dilution. Inspection of the relationships between entrainment rate and microphysical properties reveals a negative correlation between volume-mean radius and entrainment rate, suggesting the potential dominance of homogeneous mechanism in the clouds examined. In addition, entrainment rate and environmental water vapor content show similar tendencies of variation with the distance of the assumed environmental air to the cloud edges. Their variation tendencies are non-monotonic due to the relatively short distance between adjacent clouds.

  2. Nonlinear State Estimation with Missing Observations Based on Mathematical Programming

    Czech Academy of Sciences Publication Activity Database

    Pavelková, Lenka

    Praha : ÚTIA AV ČR, 2010 - (Janžura, M.; Ivánek, J.). s. 23-23 [6th International Workshop on Data – Algorithms – Decision Making. 02.12.2010-04.12.2010, Jindřichův Hradec] R&D Projects: GA MŠk 1M0572 Institutional research plan: CEZ:AV0Z10750506 Keywords : state filtering * bounded errors * missing measurements Subject RIV: BC - Control Systems Theory http://library.utia.cas.cz/separaty/2010/AS/pavelkova-nonlinear state estimation with missing observations based on mathematical programming .pdf

  3. Explaining the effects of a multifaceted intervention to improve inpatient care in rural Kenyan hospitals -- interpretation based on retrospective examination of data from participant observation, quantitative and qualitative studies

    Directory of Open Access Journals (Sweden)

    English Mike

    2011-12-01

    Full Text Available Abstract Background We have reported the results of a cluster randomized trial of rural Kenyan hospitals evaluating the effects of an intervention to introduce care based on best-practice guidelines. In parallel work we described the context of the study, explored the process and perceptions of the intervention, and undertook a discrete study on health worker motivation because this was felt likely to be an important contributor to poor performance in Kenyan public sector hospitals. Here, we use data from these multiple studies and insights gained from being participants in and observers of the intervention process to provide our explanation of how intervention effects were achieved as part of an effort to better understand implementation in low-income hospital settings. Methods Initial hypotheses were generated to explain the variation in intervention effects across place, time, and effect measure (indicator based on our understanding of theory and informed by our implementation experience and participant observations. All data sources available for hospitals considered as cases for study were then examined to determine if hypotheses were supported, rejected, or required modification. Data included transcriptions of interviews and group discussions, field notes and that from the detailed longitudinal quantitative investigation. Potentially useful explanatory themes were identified, discussed by the implementing and research team, revised, and merged as part of an iterative process aimed at building more generic explanatory theory. At the end of this process, findings were mapped against a recently reported comprehensive framework for implementation research. Results A normative re-educative intervention approach evolved that sought to reset norms and values concerning good practice and promote 'grass-roots' participation to improve delivery of correct care. Maximal effects were achieved when this strategy and external support supervision helped

  4. Towards observation based gridded runoff estimates for Europe

    Science.gov (United States)

    Gudmundsson, L.; Seneviratne, S. I.

    2014-11-01

    Terrestrial water variables are the key to understanding ecosystem processes, feed back on weather and climate, and are a prerequisite for human activities. To provide context for local investigations and to better understand phenomena that only emerge at large spatial scales, reliable information on continental scale freshwater dynamics is necessary. To date streamflow is among the best observed variables of terrestrial water systems. However, observation networks have a limited station density and often incomplete temporal coverage, limiting investigations to locations and times with observations. This paper presents a methodology to estimate continental scale runoff on a 0.5° spatial grid with monthly resolution. The methodology is based on statistical up-scaling of observed streamflow from small catchments in Europe and exploits readily available gridded atmospheric forcing data combined with the capability of machine learning techniques. The resulting runoff estimates are validated against (1) runoff from small catchments that were not used for model training, (2) river discharge from nine continental scale river basins and (3) independent estimates of long-term mean evapotranspiration at the pan-European scale. In addition it is shown that the produced gridded runoff compares on average better to observations than a multi-model ensemble of comprehensive Land Surface Models (LSMs), making it an ideal candidate for model evaluation and model development. In particular, the presented machine learning approach may help determining which factors are most relevant for an efficient modelling of runoff at regional scales. Finally, the resulting data product is used to derive a comprehensive runoff-climatology for Europe and its potential for drought monitoring is illustrated.

  5. Towards observation-based gridded runoff estimates for Europe

    Science.gov (United States)

    Gudmundsson, L.; Seneviratne, S. I.

    2015-06-01

    Terrestrial water variables are the key to understanding ecosystem processes, feed back on weather and climate, and are a prerequisite for human activities. To provide context for local investigations and to better understand phenomena that only emerge at large spatial scales, reliable information on continental-scale freshwater dynamics is necessary. To date streamflow is among the best-observed variables of terrestrial water systems. However, observation networks have a limited station density and often incomplete temporal coverage, limiting investigations to locations and times with observations. This paper presents a methodology to estimate continental-scale runoff on a 0.5° spatial grid with monthly resolution. The methodology is based on statistical upscaling of observed streamflow from small catchments in Europe and exploits readily available gridded atmospheric forcing data combined with the capability of machine learning techniques. The resulting runoff estimates are validated against (1) runoff from small catchments that were not used for model training, (2) river discharge from nine continental-scale river basins and (3) independent estimates of long-term mean evapotranspiration at the pan-European scale. In addition it is shown that the produced gridded runoff compares on average better to observations than a multi-model ensemble of comprehensive land surface models (LSMs), making it an ideal candidate for model evaluation and model development. In particular, the presented machine learning approach may help determining which factors are most relevant for an efficient modelling of runoff at regional scales. Finally, the resulting data product is used to derive a comprehensive runoff climatology for Europe and its potential for drought monitoring is illustrated.

  6. Towards observation based gridded runoff estimates for Europe

    Directory of Open Access Journals (Sweden)

    L. Gudmundsson

    2014-11-01

    Full Text Available Terrestrial water variables are the key to understanding ecosystem processes, feed back on weather and climate, and are a prerequisite for human activities. To provide context for local investigations and to better understand phenomena that only emerge at large spatial scales, reliable information on continental scale freshwater dynamics is necessary. To date streamflow is among the best observed variables of terrestrial water systems. However, observation networks have a limited station density and often incomplete temporal coverage, limiting investigations to locations and times with observations. This paper presents a methodology to estimate continental scale runoff on a 0.5° spatial grid with monthly resolution. The methodology is based on statistical up-scaling of observed streamflow from small catchments in Europe and exploits readily available gridded atmospheric forcing data combined with the capability of machine learning techniques. The resulting runoff estimates are validated against (1 runoff from small catchments that were not used for model training, (2 river discharge from nine continental scale river basins and (3 independent estimates of long-term mean evapotranspiration at the pan-European scale. In addition it is shown that the produced gridded runoff compares on average better to observations than a multi-model ensemble of comprehensive Land Surface Models (LSMs, making it an ideal candidate for model evaluation and model development. In particular, the presented machine learning approach may help determining which factors are most relevant for an efficient modelling of runoff at regional scales. Finally, the resulting data product is used to derive a comprehensive runoff-climatology for Europe and its potential for drought monitoring is illustrated.

  7. Observer-based Coal Mill Control using Oxygen Measurements

    DEFF Research Database (Denmark)

    Andersen, Palle; Bendtsen, Jan Dimon; S., Tom;

    2006-01-01

    coal flow difficult, causing stability problems and limits the plant's load following capabilities. To alleviate this problem without having to rely on expensive flow measurement equipment, a novel observer-based approach is investigated. A Kalman filter based on measurements of combustion air flow led...... against a fairly detailed, nonlinear differential equation model of the furnace and the steam circuit using data measured at a Danish power plant.......This paper proposes a novel approach to coal flow estimation in pulverized coal mills, which utilizes measurements of oxygen content in the flue gas. Pulverized coal mills are typically not equipped with sensors that detect the amount of coal injected into the furnace. This makes control of the...

  8. Strengthening the Reporting of Observational Studies in Epidemiology (STROBE)

    DEFF Research Database (Denmark)

    Vandenbroucke, Jan P; von Elm, Erik; Altman, Douglas G;

    2014-01-01

    Much medical research is observational. The reporting of observational studies is often of insufficient quality. Poor reporting hampers the assessment of the strengths and weaknesses of a study and the generalisability of its results. Taking into account empirical evidence and theoretical conside...

  9. Quality control of station-based soil moisture observations over Turkey

    Science.gov (United States)

    Tugrul Yilmaz, M.; Bulut, Burak; Cosh, Michael H.; Mladenova, Iliana

    2015-04-01

    Soil moisture is an essential variable in many hydrological applications like climate, drought, water and energy balance, weather prediction through its critical role in water and energy balance estimation. Soil moisture can be obtained using several different methods, like remote sensing-, station observation-, direct sampling-based. Station-based observations are widely used to validate satellite-based soil moisture products, making these observations to have very critical role in soil moisture estimation studies. Soil moisture observations are collected every 10 minutes since 2007 at 149 stations located over Turkey between 25.9°E - 41.8°E and 25.9°N - 41.8°N. These observation time-series are analyzed for the first time in this study for their consistency and reliability by classifying as "not reliable" and "reliable" after performing initially temperature correction and then quality control of the data.

  10. Observing Tsunamis in the Ionosphere Using Ground Based GPS Measurements

    Science.gov (United States)

    Galvan, D. A.; Komjathy, A.; Song, Y. Tony; Stephens, P.; Hickey, M. P.; Foster, J.

    2011-01-01

    Ground-based Global Positioning System (GPS) measurements of ionospheric Total Electron Content (TEC) show variations consistent with atmospheric internal gravity waves caused by ocean tsunamis following recent seismic events, including the Tohoku tsunami of March 11, 2011. We observe fluctuations correlated in time, space, and wave properties with this tsunami in TEC estimates processed using JPL's Global Ionospheric Mapping Software. These TEC estimates were band-pass filtered to remove ionospheric TEC variations with periods outside the typical range of internal gravity waves caused by tsunamis. Observable variations in TEC appear correlated with the Tohoku tsunami near the epicenter, at Hawaii, and near the west coast of North America. Disturbance magnitudes are 1-10% of the background TEC value. Observations near the epicenter are compared to estimates of expected tsunami-driven TEC variations produced by Embry Riddle Aeronautical University's Spectral Full Wave Model, an atmosphere-ionosphere coupling model, and found to be in good agreement. The potential exists to apply these detection techniques to real-time GPS TEC data, providing estimates of tsunami speed and amplitude that may be useful for future early warning systems.

  11. The Platform Design of Space-based Optical Observations of Space Debris

    Science.gov (United States)

    Chen, B. R.; Xiong, J. N.

    2016-03-01

    The basic design method of the platform for the space-based optical observations of space debris is introduced. The observation schemes of GEO (geosynchronous equatorial orbit) and LEO (low Earth orbit) debris are given respectively, including orbital parameters of platforms and pointing of telescopes, etc. Debris studied here is all from foreign catalog. According to the real orbit of space debris, the observational results of different schemes are simulated. By studying single platform, the optimal observing altitude for GEO debris and the optimal telescope's deflection angles at different altitudes for LEO debris are given. According to these, multi-platforms observation networks are designed. By analyzing the advantages and disadvantages of each scheme, it can provide reference for the application of space-based optical debris observation.

  12. [Economic assessment, a field between clinical research and observational studies].

    Science.gov (United States)

    Launois, Robert

    2003-01-01

    Health technology assessments propose to study the differential impact of health interventions in a complex care system which is characterised by the multitude of individual behaviours and the diverse nature of the institutions involved. Current systems for data collection lend themselves poorly to this rigorous analysis of efficacy of treatments in the actual situations where they are used. Randomised trials endeavour to neutralise any parasitic interference which could compromise testing for a causal relationship between the treatment administered and the result obtained. Their methodology which establishes the term ceteris paribus in the principle of good practice lends itself poorly to an analysis of individual behaviour. Observational studies are start from actual treatment situations to describe them as reliably as possible. By definition, however, these assume that the natural course of events is not deviated by any intervention. The absence of an experimental plan increases the likelihood of bias and makes it more difficult to test for causal relationships. They lend themselves poorly to testing for incremental efficacy. The two instruments to be preferred are decisional analysis and quasi-experimental studies. Decisional analysis help to avoid the problems of external validity associated with randomised clinical trials by associating parameters which are extracted from data obtained from everyday practice. Quasi-experimental studies or pragmatic trials are based on the reality of behaviour of the prescriber and his/her patients; their impact on efficacy, quality of life social costs of the disease and of treatments may be identified under normal conditions of use. PMID:12609811

  13. Cloud cover retrieved from ground-base observation using Skyviewer : A validation with human observations

    Science.gov (United States)

    Kim, Bu-Yo; Jee, Joon-Bum; Zo, Il-Sung; Lee, Kyu-Tae

    2016-04-01

    Cloud cover is used in various fields of research in addition to weather forecasts; however, the ground observation of cloud cover is conducted by human observers, a method with low objectivity, temporal and spatial resolutions. Therefore, to address these problems, we have developed an improved algorithm to calculate cloud cover using sky image data obtained with Skyviewer equipment. The algorithm uses a variable threshold of the Red Blue Ratio (RBR) determined from the frequency distributions of the Green Blue Ratio (GBR) to calculate cloud cover more accurately than existing algorithms. To verify the accuracy of the algorithm, we conducted daily, monthly, seasonal and yearly statistical analysis on human observations of cloud cover obtained every hour from 0800 to 1700 LST for the entire year of 2012 at Gangwon Regional Meteorological Administration (GRMA), Korea. A daily case study compared the images of 1200 LST cases by season and pixel images of cloud cover calculated by the algorithm. The selected weekly cases yielded a high correlation of 0.93 with GRMA data. A monthly case study showed low RMSEs and high correlations for December (RMSE=1.64 tenths and r=0.92) and August (RMSE=1.43 tenths and r=0.91). In addition, seasonal cases yielded a high correlation of 0.9 and 87% consistency within ±2 tenths for winter and a correlation of 0.83 and 82% consistency for summer, when cases of cloud-free or overcast conditions are frequent. Annual analysis showed that the bias of GRMA and Skyviewer for the year of 2012 was -0.36 tenth, with cloud cover of the GRMA data being greater, whilst RMSE was 2.12 tenths. Considering the spatial inconsistency of the data used in the analysis, GRMA and Skyviewer showed a high correlation (0.87) and 80% consistency for cases with a difference in cloud cover of within ±2 tenths.

  14. Process observation in fiber laser-based selective laser melting

    Science.gov (United States)

    Thombansen, Ulrich; Gatej, Alexander; Pereira, Milton

    2015-01-01

    The process observation in selective laser melting (SLM) focuses on observing the interaction point where the powder is processed. To provide process relevant information, signals have to be acquired that are resolved in both time and space. Especially in high-power SLM, where more than 1 kW of laser power is used, processing speeds of several meters per second are required for a high-quality processing results. Therefore, an implementation of a suitable process observation system has to acquire a large amount of spatially resolved data at low sampling speeds or it has to restrict the acquisition to a predefined area at a high sampling speed. In any case, it is vitally important to synchronously record the laser beam position and the acquired signal. This is a prerequisite that allows the recorded data become information. Today, most SLM systems employ f-theta lenses to focus the processing laser beam onto the powder bed. This report describes the drawbacks that result for process observation and suggests a variable retro-focus system which solves these issues. The beam quality of fiber lasers delivers the processing laser beam to the powder bed at relevant focus diameters, which is a key prerequisite for this solution to be viable. The optical train we present here couples the processing laser beam and the process observation coaxially, ensuring consistent alignment of interaction zone and observed area. With respect to signal processing, we have developed a solution that synchronously acquires signals from a pyrometer and the position of the laser beam by sampling the data with a field programmable gate array. The relevance of the acquired signals has been validated by the scanning of a sample filament. Experiments with grooved samples show a correlation between different powder thicknesses and the acquired signals at relevant processing parameters. This basic work takes a first step toward self-optimization of the manufacturing process in SLM. It enables the

  15. Influence of treatment with alendronate on the speed of sound, an ultrasound parameter, of the calcaneus in postmenopausal Japanese women with osteoporosis: a clinical practice-based observational study

    OpenAIRE

    Iwamoto J; Takada T; Sato Y; Matsumoto H

    2012-01-01

    Jun Iwamoto,1 Tetsuya Takada,2 Yoshihiro Sato,3 Hideo Matsumoto11Institute for Integrated Sports Medicine, Keio University School of Medicine, Tokyo, 2Department of Internal Medicine, Hiyoshi Medical Clinic, Kanagawa, 3Department of Neurology, Mitate Hospital, Fukuoka, JapanPurpose: The influence of alendronate (ALN) treatment on the quantitative ultrasound parameters of the calcaneus remains to be established in Japanese patients. The aim of the present clinical practice-based observational ...

  16. Estudio preliminar del uso de un protocolo para evaluar el bienestar de vacas lecheras usando observaciones basadas en el animal Preliminary study of the use of a protocol to assess the welfare of dairy cattle using animal-based observations

    Directory of Open Access Journals (Sweden)

    C Arraño

    2007-01-01

    Full Text Available El objetivo del presente estudio fue evaluar el bienestar de vacas de lechería usando un protocolo simplificado de observaciones basadas en el animal. Las 22 lecherías se visitaron por una sola vez entre marzo y junio del 2005. Las lecherías fueron seleccionadas por conveniencia, tomando en cuenta la disposición del propietario para participar, su facilidad de acceso y el tamaño del rebaño (291 ± 71,6. De las 22 lecherías, 5 de ellas mantenían a sus vacas a pradera; de las 17 restantes, 4 tenían estabulación permanente y 13 las mantenían estabuladas durante la noche. La visita comenzó dos horas antes de la ordeña de la tarde; durante la visita los animales fueron observados sistemáticamente al momento de la ordeña, para evaluar la condición física y el comportamiento. Las observaciones recopiladas fueron ingresadas a una planilla electrónica Microsoft® Excel XP. Los resultados encontrados para las indicadores de bienestar basados en observaciones de los animales se agruparon en cinco categorías (A: lo mejor/ E: lo peor, luego las granjas fueron ordenadas de acuerdo al porcentaje de indicadores en cada categoría. Las 22 lecherías tuvieron al menos un indicador en la categoría A. Una sola lechería logró tener cinco indicadores de los siete observados, en la categoría A. El indicador mejor evaluado fue la condición corporal, y el peor evaluado fue la "zona de fuga" de las vacas. Se concluye que ninguna lechería tuvo resultados consistentemente buenos o malos en relación a las demás, al evaluar el bienestar de las vacas mediante observaciones basadas en el animalThe aim of this study was to evaluate the welfare of dairy cows using a simplified protocol of animal-based observations. Twenty-two commercial dairy farms in the province of Valdivia, Chile, were visited once between March and July 2005. The farms were selected considering the willingness of the owners to participate, distance from the university and size of

  17. Data base management study

    Science.gov (United States)

    1976-01-01

    Data base management techniques and applicable equipment are described. Recommendations which will assist potential NASA data users in selecting and using appropriate data base management tools and techniques are presented. Classes of currently available data processing equipment ranging from basic terminals to large minicomputer systems were surveyed as they apply to the needs of potential SEASAT data users. Cost and capabilities projections for this equipment through 1985 were presented. A test of a typical data base management system was described, as well as the results of this test and recommendations to assist potential users in determining when such a system is appropriate for their needs. The representative system tested was UNIVAC's DMS 1100.

  18. Tropospheric nitrogen dioxide column retrieval based on ground-based zenith-sky DOAS observations

    Science.gov (United States)

    Tack, F. M.; Hendrick, F.; Pinardi, G.; Fayt, C.; Van Roozendael, M.

    2013-12-01

    A retrieval approach has been developed to derive tropospheric NO2 vertical column amounts from ground-based zenith-sky measurements of scattered sunlight. Zenith radiance spectra are observed in the visible range by the BIRA-IASB Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) instrument and analyzed by the DOAS technique, based on a least-squares spectral fitting. In recent years, this technique has shown to be a well-suited remote sensing tool for monitoring atmospheric trace gases. The retrieval algorithm is developed and validated based on a two month dataset acquired from June to July 2009 in the framework of the Cabauw (51.97° N, 4.93° E) Intercomparison campaign for Nitrogen Dioxide measuring Instruments (CINDI). Once fully operational, the retrieval approach can be applied to observations from stations of the Network for the Detection of Atmospheric Composition Change (NDACC). The obtained tropospheric vertical column amounts are compared with the multi-axis retrieval from the BIRA-IASB MAX-DOAS instrument and the retrieval from a zenith-viewing only SAOZ instrument (Système d'Analyse par Observations Zénithales), owned by Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS). First results show a good agreement for the whole time series with the multi-axis retrieval (R = 0.82; y = 0.88x + 0.30) as well as with the SAOZ retrieval (R = 0.85; y = 0.76x + 0.28 ). Main error sources arise from the uncertainties in the determination of tropospheric and stratospheric air mass factors, the stratospheric NO2 abundances and the residual amount in the reference spectrum. However zenith-sky measurements have been commonly used over the last decades for stratospheric monitoring, this study also illustrates the suitability for retrieval of tropospheric column amounts. As there are long time series of zenith-sky acquisitions available, the developed approach offers new perspectives with regard to the use of observations from the NDACC

  19. Robust observer-based adaptive fuzzy sliding mode controller

    Science.gov (United States)

    Oveisi, Atta; Nestorović, Tamara

    2016-08-01

    In this paper, a new observer-based adaptive fuzzy integral sliding mode controller is proposed based on the Lyapunov stability theorem. The plant is subjected to a square-integrable disturbance and is assumed to have mismatch uncertainties both in state- and input-matrices. Based on the classical sliding mode controller, the equivalent control effort is obtained to satisfy the sufficient requirement of sliding mode controller and then the control law is modified to guarantee the reachability of the system trajectory to the sliding manifold. In order to relax the norm-bounded constrains on the control law and solve the chattering problem of sliding mode controller, a fuzzy logic inference mechanism is combined with the controller. An adaptive law is then introduced to tune the parameters of the fuzzy system on-line. Finally, for evaluating the controller and the robust performance of the closed-loop system, the proposed regulator is implemented on a real-time mechanical vibrating system.

  20. Feasibility, acceptability, and effectiveness of family-based treatment for adolescent anorexia nervosa: an observational study conducted in Brazil Viabilidade, aceitação e eficácia do tratamento familiar para anorexia nervosa em adolescentes: um estudo observacional no Brasil

    OpenAIRE

    Gizela Turkiewicz; Vanessa Pinzon; James Lock; Bacy Fleitlich-Bilyk

    2010-01-01

    OBJECTIVE: There is strong evidence that family-based treatment is effective in cases of adolescent anorexia nervosa. Although family-based treatment has been studied in English-speaking countries, there is a need to examine the generalizability of this approach to non-English speaking cultures. This pilot-study aimed to examine the feasibility, acceptability, and effectiveness of family-based treatment in Brazil. METHOD: Observational study of adolescents with anorexia nervosa (excluding men...

  1. In-Hospital Recruitment to Observational Studies of Stroke

    Science.gov (United States)

    Pickering, Ruth M.; Kunkel, Dorit; Fitton, Carolyn; Ashburn, Ann; Jenkinson, Damian

    2010-01-01

    The objective of this study was to examine recruitment in three observational follow-up studies of patients with stroke, focusing on reasons for nonparticipation and the role of potential factors in explaining recruitment rates. It comprised secondary analysis of the three studies. Recruitment rates varied between the studies. Between 10 and 50%…

  2. Simulation Study Of Early Afterglows Observed With Swift

    Science.gov (United States)

    Nishikawa, Ken-Ichi; Hededal, C.; Hardee, P.; Mizuno, Y.; Fishman, G. J.

    2006-09-01

    A 3-D relativistic particle-in-cell code has been used to simulate the dynamics of forward and reverse shocks with thin and thick shells within the parameter constraints provided by present Swift observations and the present models of GRB emission. Our 3-D RPIC simulations have provided the dynamics of collisionless shocks in electron-ion and electron-positron plasmas with and without initial ambient magnetic fields and revealed the importance of ``jitter radiation'' with prompt and afterglow spectra due to the inhomogeneous magnetic fields generated by the Weibel instability. It is different from synchrotron radiation, which is usually assumed to be the dominant radiation process. We have investigated gamma-ray burst emissions from prompt, early, and late afterglows considering microscopic processes. Based on our previous investigation of the Weibel instability for each stage of evolution of ejecta propagating in the ISM, we have incorporated the plasma conditions (relativistic jets) with the density and composition of the plasmas, the magnetic field strength ($\\sigma$-values (the ratio of the electromagnetic energy flux to the particle energy flux)) and its direction, and the Lorentz factor for the different stages in prompt and afterglows. Systematic simulation studies of the relativistic collisionless shocks, associated particle acceleration, magnetic field generation and self-consistent radiation provide insight into undetermined issues in prompt and afterglows observed by Swift. Self-consistently calculated lightcurves, spectra, spectral evolutions, and polarization as function of viewing angle will be done to light a shed on recent new observations by Swift, in particular, X-ray flares, early steep decay, and shallow decay.

  3. An Observed Voting System Based On Biometric Technique

    Directory of Open Access Journals (Sweden)

    B. Devikiruba

    2015-08-01

    Full Text Available ABSTRACT This article describes a computational framework which can run almost on every computer connected to an IP based network to study biometric techniques. This paper discusses with a system protecting confidential information puts strong security demands on the identification. Biometry provides us with a user-friendly method for this identification and is becoming a competitor for current identification mechanisms. The experimentation section focuses on biometric verification specifically based on fingerprints. This article should be read as a warning to those thinking of using methods of identification without first examine the technical opportunities for compromising mechanisms and the associated legal consequences. The development is based on the java language that easily improves software packages that is useful to test new control techniques.

  4. SCHeMA web-based observation data information system

    Science.gov (United States)

    Novellino, Antonio; Benedetti, Giacomo; D'Angelo, Paolo; Confalonieri, Fabio; Massa, Francesco; Povero, Paolo; Tercier-Waeber, Marie-Louise

    2016-04-01

    It is well recognized that the need of sharing ocean data among non-specialized users is constantly increasing. Initiatives that are built upon international standards will contribute to simplify data processing and dissemination, improve user-accessibility also through web browsers, facilitate the sharing of information across the integrated network of ocean observing systems; and ultimately provide a better understanding of the ocean functioning. The SCHeMA (Integrated in Situ Chemical MApping probe) Project is developing an open and modular sensing solution for autonomous in situ high resolution mapping of a wide range of anthropogenic and natural chemical compounds coupled to master bio-physicochemical parameters (www.schema-ocean.eu). The SCHeMA web system is designed to ensure user-friendly data discovery, access and download as well as interoperability with other projects through a dedicated interface that implements the Global Earth Observation System of Systems - Common Infrastructure (GCI) recommendations and the international Open Geospatial Consortium - Sensor Web Enablement (OGC-SWE) standards. This approach will insure data accessibility in compliance with major European Directives and recommendations. Being modular, the system allows the plug-and-play of commercially available probes as well as new sensor probess under development within the project. The access to the network of monitoring probes is provided via a web-based system interface that, being implemented as a SOS (Sensor Observation Service), is providing standard interoperability and access tosensor observations systems through O&M standard - as well as sensor descriptions - encoded in Sensor Model Language (SensorML). The use of common vocabularies in all metadatabases and data formats, to describe data in an already harmonized and common standard is a prerequisite towards consistency and interoperability. Therefore, the SCHeMA SOS has adopted the SeaVox common vocabularies populated by

  5. Space-based Observations of the Solar Irradiance

    Science.gov (United States)

    Woods, Thomas N.

    2015-08-01

    Solar photon radiation is the dominant energy input to the Earth system, and this energy determines the temperature, structure, and dynamics of the atmosphere, warms the Earth surface, and sustains life. Observations of true solar variability became possible only after attaining access to space, so the observational record of the solar irradiance for sun-climate studies extends back only about 40 years. The total solar irradiance (TSI) and solar spectral irradiance (SSI) observations will be presented along with the discussion of the solar variability during the past four decades. The solar radiation varies on all time scales ranging from minutes to hours for solar eruptive events (flares), days to months for active region evolution and solar rotation (~27 days), and years to decades over the solar activity cycle (~11 years). The amount of solar variability is highly dependent on wavelength and ranges from orders of magnitude for the X-ray to 10-60% for part of the ultraviolet to only 0.1% for the visible and infrared. The accuracy and precision of the solar irradiance measurements have steadily improved with each new generation of instrumentation and with new laboratory (pre-flight) calibration facilities.

  6. Observational Selection Effects with Ground-based Gravitational Wave Detectors

    CERN Document Server

    Chen, Hsin-Yu; Vitale, Salvatore; Holz, Daniel E; Katsavounidis, Erik

    2016-01-01

    Ground-based interferometers are not perfectly all-sky instruments, and it is important to account for their behavior when considering the distribution of detected events. In particular, the LIGO detectors are most sensitive to sources above North America and the Indian Ocean and, as the Earth rotates, the sensitive regions are swept across the sky. However, because the detectors do not acquire data uniformly over time, there is a net bias on detectable sources' right ascensions. Both LIGO detectors preferentially collect data during their local night; it is more than twice as likely to be local midnight than noon when both detectors are operating. We discuss these selection effects and how they impact LIGO's observations and electromagnetic follow-up. Beyond galactic foregrounds associated with seasonal variations, we find that equatorial observatories can access over $80\\%$ of the localization probability, while mid-latitudes will access closer to $70\\%$. Facilities located near the two LIGO sites can obser...

  7. Chaotic observer-based synchronization under information constraints

    Science.gov (United States)

    Fradkov, Alexander L.; Andrievsky, Boris; Evans, Robin J.

    2006-06-01

    Limitations of observer-based synchronization systems under information constraints (limited information capacity of the coupling channel) are evaluated. We give theoretical analysis for multidimensional drive-response systems represented in the Lurie form (linear part plus nonlinearity depending only on measurable outputs). It is shown that the upper bound of the limit synchronization error (LSE) is proportional to the upper bound of the transmission error. As a consequence, the upper and lower bounds of LSE are proportional to the maximum rate of the coupling signal and inversely proportional to the information transmission rate (channel capacity). Optimality of the binary coding for coders with one-step memory is established. The results are applied to synchronization of two chaotic Chua systems coupled via a channel with limited capacity.

  8. The EULAR Study Group for Registers and Observational Drug Studies

    DEFF Research Database (Denmark)

    Kearsley-Fleet, Lianne; Závada, Jakub; Hetland, Merete Lund;

    2015-01-01

    OBJECTIVE: Under the auspices of the European League Against Rheumatism (EULAR), a study group of investigators representing European biologic DMARD (bDMARD) registers was convened. The purpose of this initial assessment was to collect and compare a cross section of patient characteristics and...

  9. PolarBase: a data base of high resolution spectropolarimetric stellar observations

    OpenAIRE

    Petit, P.; Louge, T.; Théado, S.; Paletou, F; Manset, N.; Morin, J.; Marsden, S. C.; Jeffers, S. V.

    2014-01-01

    PolarBase is an evolving data base that contains all stellar data collected with the ESPaDOnS and NARVAL high-resolution spectropolarimeters, in their reduced form, as soon as they become public. As of early 2014, observations of 2,000 stellar objects throughout the Hertzsprung-Russell diagram are available. Intensity spectra are available for all targets, and the majority of the observations also include simultaneous spectra in circular or linear polarization, with the majority of the polari...

  10. Multisatellite and ground-based observations of transient ULF waves

    International Nuclear Information System (INIS)

    A unique alignment of the Active Magnetospheric Particle Tracer Explorers (AMPTE) CCE and Viking satellites with respect to the EISCAT Magnetometer Cross has provided an opportunity to study transient ULF pulsations associated with variations in solar wind plasma density observed by the IMP 8 satellite. These observations were acquired during a relatively quiet period on April 24, 1986, during the Polar Region and Outer Magnetosphere International Study (PROMIS) period. An isolated 4-mHz (4-min period) pulsation was detected on the ground which was associated with transverse magnetic field oscillations observed by Viking at a ∼ 2-RE altitude above the auroral zone and by CCE at ∼ 8-RE in the equatorial plane on nearly the same flux tube. CCE detected a compressional oscillation in the magnetic field with twice the period (∼ 10 min) of the transverse waves, and with a waveform nearly identical to an isolated oscillation in the solar wind plasma density measured by IMP 8. The authors conclude that the isolated 10-min oscillation in solar wind plasma density produced magnetic field compression oscillations inside the magnetosphere at the same frequency which also enhanced resonant oscillations at approximately twice the frequency that were already present. The ground magnetic field variations are due to ionospheric Hall currents driven by the electric field of the standing Alfven waves. The time delay between surface and satellite data acquired at different local times supports the conclusion that the periodic solar wind density variation excites a tailward traveling large-scale magnetosphere wave train which excites local field line resonant oscillations. They conclude that these transient magnetic field variations are not associated with magnetic field reconnection or flux transfer events

  11. Observer Based Fault Detection and Moisture Estimating in Coal Mill

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Mataji, Babak

    2008-01-01

    the general performance of power plants. Detection  of faults and moisture content estimation are consequently of high interest in the handling of the problems caused by faults and moisture content. The coal flow out of the mill is the obvious variable to monitor, when detecting non-intended drops in......In this paper an observer-based method for detecting faults and estimating moisture content in the coal in coal mills is presented. Handling of faults and operation under special conditions, such as high moisture content in the coal, are of growing importance due to the increasing requirements to...... the coal flow out of the coal mill. However, this variable is not measurable. Another estimated variable is the moisture content, which is only "measurable" during steady-state operations of the coal mill. Instead, this paper suggests a method where these unknown variables are estimated based on a...

  12. Quality of Systematic Reviews of Observational Nontherapeutic Studies

    OpenAIRE

    Shamliyan, Tatyana; Kane, Robert L; Jansen, Stacy

    2010-01-01

    Introduction High-quality epidemiologic research is essential in reducing chronic diseases. We analyzed the quality of systematic reviews of observational nontherapeutic studies. Methods We searched several databases for systematic reviews of observational nontherapeutic studies that examined the prevalence of or risk factors for chronic diseases and were published in core clinical journals from 1966 through June 2008. We analyzed the quality of such reviews by using prespecified criteria and...

  13. Grid-based platform for training in Earth Observation

    Science.gov (United States)

    Petcu, Dana; Zaharie, Daniela; Panica, Silviu; Frincu, Marc; Neagul, Marian; Gorgan, Dorian; Stefanut, Teodor

    2010-05-01

    GiSHEO platform [1] providing on-demand services for training and high education in Earth Observation is developed, in the frame of an ESA funded project through its PECS programme, to respond to the needs of powerful education resources in remote sensing field. It intends to be a Grid-based platform of which potential for experimentation and extensibility are the key benefits compared with a desktop software solution. Near-real time applications requiring simultaneous multiple short-time-response data-intensive tasks, as in the case of a short time training event, are the ones that are proved to be ideal for this platform. The platform is based on Globus Toolkit 4 facilities for security and process management, and on the clusters of four academic institutions involved in the project. The authorization uses a VOMS service. The main public services are the followings: the EO processing services (represented through special WSRF-type services); the workflow service exposing a particular workflow engine; the data indexing and discovery service for accessing the data management mechanisms; the processing services, a collection allowing easy access to the processing platform. The WSRF-type services for basic satellite image processing are reusing free image processing tools, OpenCV and GDAL. New algorithms and workflows were develop to tackle with challenging problems like detecting the underground remains of old fortifications, walls or houses. More details can be found in [2]. Composed services can be specified through workflows and are easy to be deployed. The workflow engine, OSyRIS (Orchestration System using a Rule based Inference Solution), is based on DROOLS, and a new rule-based workflow language, SILK (SImple Language for worKflow), has been built. Workflow creation in SILK can be done with or without a visual designing tools. The basics of SILK are the tasks and relations (rules) between them. It is similar with the SCUFL language, but not relying on XML in

  14. Evidence of clinical competence by simulation, a hermeneutical observational study.

    Science.gov (United States)

    Lejonqvist, Gun-Britt; Eriksson, Katie; Meretoja, Riitta

    2016-03-01

    Making the transition from theory to practise easier in nursing education through simulation is widely implemented all over the world, and there is research evidence of the positive effects of simulation. The pre-understanding for this study is based on a definition of clinical competence as encountering, knowing, performing, maturing and developing, and the hypothesis is that these categories should appear in simulated situations. The aim of the study was to explore the forms and expressions of clinical competence in simulated situations and furthermore to explore if and how clinical competence could be developed by simulation. An observational hermeneutic study with a hypothetic-deductive approach was used in 18 simulated situations with 39 bachelor degree nursing students. In the situations, the scenarios, the actors and the plots were described. The story told was "the way from suffering to health" in which three main plots emerged. The first was, doing as performing and knowing, which took the shape of knowing what to do, acting responsibly, using evidence and equipment, appearing confident and feeling comfortable, and sharing work and information with others. The second was, being as encountering the patient, which took the shape of being there for him/her and confirming by listening and answering. The third plot was becoming as maturing and developing which took the shape of learning in co-operation with other students. All the deductive categories, shapes and expressions appeared as dialectic patterns having their negative counterparts. The study showed that clinical competence can be made evident and developed by simulation and that the challenge is in encountering the patient and his/her suffering. PMID:26763209

  15. Magnetospheric Response to Interplanetary Field Enhancements: Coordinated Space-based and Ground-based Observations

    Science.gov (United States)

    Chi, Peter; Russell, Christopher; Lai, Hairong

    2014-05-01

    In general, asteroids, meteoroids and dust do not interact with the plasma structures in the solar system, but after a collision between fast moving bodies the debris cloud contains nanoscale dust particles that are charged and behave like heavy ions. Dusty magnetic clouds are then accelerated to the solar wind speed. While they pose no threat to spacecraft because of the particle size, the coherency imposed by the magnetization of the cloud allows the cloud to interact with the Earth's magnetosphere as well as the plasma in the immediate vicinity of the cloud. We call these clouds Interplanetary Field Enhancements (IFEs). These IFEs are a unique class of interplanetary field structures that feature cusp-shaped increases and decreases in the interplanetary magnetic field and a thin current sheet. The occurrence of IFEs is attributed to the interaction between the solar wind and dust particles produced in inter-bolide collisions. Previous spacecraft observations have confirmed that IFEs move with the solar wind. When IFEs strike the magnetosphere, they may distort the magnetosphere in several possible ways, such as producing a small indentation, a large scale compression, or a glancing blow. In any event if the IFE is slowed by the magnetosphere, the compression of the Earth's field should be seen in the ground-based magnetic records that are continuously recorded. Thus it is important to understand the magnetospheric response to IFE arrival. In this study, we investigate the IFE structure observed by spacecraft upstream of the magnetosphere and the induced magnetic field perturbations observed by networks of ground magnetometers, including the THEMIS, CARISMA, McMAC arrays in North America and the IMAGE array in Europe. We find that, in a well-observed IFE event on December 24, 2006, all ground magnetometer stations observed an impulse at approximately 1217 UT when the IFE was expected to arrive at the Earth's magnetopause. These ground stations spread across many

  16. Simulation study for measurement of horizontal wind profiles in the polar stratosphere and mesosphere using ground-based observations of ozone and carbon monoxide lines in the 230-250 GHz region

    Science.gov (United States)

    Newnham, David A.; Ford, George P.; Moffat-Griffin, Tracy; Pumphrey, Hugh C.

    2016-07-01

    Meteorological and atmospheric models are being extended up to 80 km altitude but there are very few observing techniques that can measure stratospheric-mesospheric winds at altitudes between 20 and 80 km to verify model datasets. Here we demonstrate the feasibility of horizontal wind profile measurements using ground-based passive millimetre-wave spectroradiometric observations of ozone lines centred at 231.28, 249.79, and 249.96 GHz. Vertical profiles of horizontal winds are retrieved from forward and inverse modelling simulations of the line-of-sight Doppler-shifted atmospheric emission lines above Halley station (75°37' S, 26°14' W), Antarctica. For a radiometer with a system temperature of 1400 K and 30 kHz spectral resolution observing the ozone 231.28 GHz line we estimate that 12 h zonal and meridional wind profiles could be determined over the altitude range 25-74 km in winter, and 28-66 km in summer. Height-dependent measurement uncertainties are in the range 3-8 m s-1 and vertical resolution ˜ 8-16 km. Under optimum observing conditions at Halley a temporal resolution of 1.5 h for measuring either zonal or meridional winds is possible, reducing to 0.5 h for a radiometer with a 700 K system temperature. Combining observations of the 231.28 GHz ozone line and the 230.54 GHz carbon monoxide line gives additional altitude coverage at 85 ± 12 km. The effects of clear-sky seasonal mean winter/summer conditions, zenith angle of the received atmospheric emission, and spectrometer frequency resolution on the altitude coverage, measurement uncertainty, and height and time resolution of the retrieved wind profiles have been determined.

  17. Observer-based and Regression Model-based Detection of Emerging Faults in Coal Mills

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Lin, Bao; Jørgensen, Sten Bay

    2006-01-01

    In order to improve the reliability of power plants it is important to detect fault as fast as possible. Doing this it is interesting to find the most efficient method. Since modeling of large scale systems is time consuming it is interesting to compare a model-based method with data driven ones....... In this paper three different fault detection approaches are compared using a example of a coal mill, where a fault emerges. The compared methods are based on: an optimal unknown input observer, static and dynamic regression model-based detections. The conclusion on the comparison is that observer...

  18. Assessing the mitigation potential of agricultural systems by optimization of the agricultural management: A modeling study on 8 agricultural observation sites across Europe with the process based model LandscapeDNDC

    Science.gov (United States)

    Molina Herrera, Saul; Haas, Edwin; Klatt, Steffen; Kraus, David; Kiese, Ralf; Butterbach-Bahl, Klaus

    2014-05-01

    The use of mineral nitrogen (N) fertilizers increase crop yields but cause the biggest anthropogenic source of nitrous oxide (N2O) emissions and strongly contribute to surface water eutrophication (e.g. nitrate leaching). The necessity to identify affordable strategies that improve crop production while improving ecosystem services are in continuous debate between policy decision makers and farmers. In this line, a lack commitment from farmers to enforce laws might result in the reduction of benefits. For this reason, farmers should aim to increase crop production and to reduce environmental harm by the adoption of precision climate smart agriculture tools applied to management practices for instance. In this study we present optimized strategies for 8 sites (agricultural and grassland ecosystems) with long term field observation across Europe to show the mitigation potential to reduce reactive nitrogen losses under the constrain of keeping yields at observed levels. LandscapeDNDC simulations of crop yields and associated nitrogen losses (N2O emissions and NO3 leaching) were evaluated against long term field measurements. The sites presented different management regimes including the main commodity crops (maize, wheat, barley, rape seeds, etc) and fertilization amendments (synthetic and organic fertilizers) in Europe. The simulations reproduced the observed yields, captured N2O emissions and NO3 leaching losses with high statistical presicion (r2), acurrency (ME) and agreement (RMSPEn). The mitigation potentials to reduce N losses while keeping yields at observed levels for all 8 sites were assesed by Monte Carlo optimizations of the individual underlying multi year agricultural management options (timings of planting and harvest, fertilization & manure applications and rates, residues management). In this study we present for all 8 agricultural observations sites their individual mitigation potentials to reduce N losses for multi year rotations. The conclusions

  19. Explaining the effects of a multifaceted intervention to improve inpatient care in rural Kenyan hospitals -- interpretation based on retrospective examination of data from participant observation, quantitative and qualitative studies

    OpenAIRE

    English Mike; Nzinga Jacinta; Mbindyo Patrick; Ayieko Philip; Irimu Grace; Mbaabu Lairumbi

    2011-01-01

    Abstract Background We have reported the results of a cluster randomized trial of rural Kenyan hospitals evaluating the effects of an intervention to introduce care based on best-practice guidelines. In parallel work we described the context of the study, explored the process and perceptions of the intervention, and undertook a discrete study on health worker motivation because this was felt likely to be an important contributor to poor performance in Kenyan public sector hospitals. Here, we ...

  20. Disturbance observer based control system design for inertially stabilized platform

    Science.gov (United States)

    Wu, Chunnan; Lin, Zhe

    2012-09-01

    Inertially stabilized platform (ISP) is indispensable for various imaging systems to segregate the base angular movement and achieve high LOS (Line-Of-Sight) stability. The disturbance rejection ratio and command following performance are of primary concern in designing ISP control systems. In this paper, the redundant gimbals ISP system is considered and it is shown to experience complex disturbance and parameter variation during operation. To meet advanced LOS stabilization requirement, a disturbance observer based (DOB) dual-loop controller design for ISP is proposed of which the DOB is the internal-loop. Using a nominal plant model and a low-pass filter, the disturbance signal is estimated and used as a cancellation input added to the current command of torque motor. If the DOB works well, the disturbance torque and mismatch between nominal plant and actual plant will be compensated and the internal-loop will behave as nominal model parameters. On the other hand, the external-loop will be designed for nominal model parameters to meet stabilization requirements. This paper will mainly focus on the DOB design method. Since the low-pass filter of DOB determines the sensitivity and complementary sensitivity function as will be shown in this paper, designing the filter is the most important consideration. In this paper, an optimal low-pass filter design method is proposed. The method is intuitive, simple to implement and allows on-line tuning. Simulation results show the performance enhancement of our control structure in the presence of disturbance and measurement noise.

  1. CEOS Contributions to Informing Energy Management and Policy Decision Making Using Space-Based Earth Observations

    Science.gov (United States)

    Eckman, Richard S.

    2009-01-01

    Earth observations are playing an increasingly significant role in informing decision making in the energy sector. In renewable energy applications, space-based observations now routinely augment sparse ground-based observations used as input for renewable energy resource assessment applications. As one of the nine Group on Earth Observations (GEO) societal benefit areas, the enhancement of management and policy decision making in the energy sector is receiving attention in activities conducted by the Committee on Earth Observation Satellites (CEOS). CEOS has become the "space arm" for the implementation of the Global Earth Observation System of Systems (GEOSS) vision. It is directly supporting the space-based, near-term tasks articulated in the GEO three-year work plan. This paper describes a coordinated program of demonstration projects conducted by CEOS member agencies and partners to utilize Earth observations to enhance energy management end-user decision support systems. I discuss the importance of engagement with stakeholders and understanding their decision support needs in successfully increasing the uptake of Earth observation products for societal benefit. Several case studies are presented, demonstrating the importance of providing data sets in formats and units familiar and immediately usable by decision makers. These projects show the utility of Earth observations to enhance renewable energy resource assessment in the developing world, forecast space-weather impacts on the power grid, and improve energy efficiency in the built environment.

  2. CEOS contributions to informing energy management and policy decision making using space-based Earth observations

    International Nuclear Information System (INIS)

    Earth observations are playing an increasingly significant role in informing decision making in the energy sector. In renewable energy applications, space-based observations now routinely augment sparse ground-based observations used as input for renewable energy resource assessment applications. As one of the nine Group on Earth Observations (GEO) societal benefit areas, the enhancement of management and policy decision making in the energy sector is receiving attention in activities conducted by the Committee on Earth Observation Satellites (CEOS). CEOS has become the “space arm” for the implementation of the Global Earth Observation System of Systems (GEOSS) vision. It is directly supporting the space-based, near-term tasks articulated in the GEO three-year work plan. This paper describes a coordinated program of demonstration projects conducted by CEOS member agencies and partners to utilize Earth observations to enhance energy management end-user decision support systems. We discuss the importance of engagement with stakeholders and understanding their decision support needs in successfully increasing the uptake of Earth observation products for societal benefit. Several case studies are presented, demonstrating the importance of providing data sets in formats and units familiar and immediately usable by decision makers. These projects show the utility of Earth observations to enhance renewable energy resource assessment in the developing world, forecast space weather impacts on the power grid, and improve energy efficiency in the built environment.

  3. Acceptability and feasibility of mHealth and community-based directly observed antiretroviral therapy to prevent mother-to-child HIV transmission in South African pregnant women under Option B+: an exploratory study

    Directory of Open Access Journals (Sweden)

    Nachega JB

    2016-04-01

    Full Text Available Jean B Nachega,1,2 Donald Skinner,3 Larissa Jennings,4 Jessica F Magidson,5 Frederick L Altice,6 Jessica G Burke,7 Richard T Lester,8 Olalekan A Uthman,9,10 Amy R Knowlton,11 Mark F Cotton,12 Jean R Anderson,13 Gerhard B Theron14 1Department of Epidemiology, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA, USA; 2Department of Medicine, Centre for Infectious Diseases, and ACTG Clinical Trial Unit (CTU/Family Clinical Research Unit (FAMCRU, 3Research on Health and Society, Department of Interdisciplinary Health Studies, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa; 4Social and Behavioral Interventions Program, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 5Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 6Division of Infectious Diseases, AIDS Program, Yale University School of Medicine, New Haven, CT, 7Department of Behavioral and Community Health, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA, USA; 8Department of Medicine, Division of Infectious Diseases, University of British Columbia, Vancouver, BC, Canada; 9Warwick Centre for Applied Health Research and Delivery (WCAHRD, Division of Health Sciences, Warwick Medical School, The University of Warwick, Coventry, UK; 10Centre for Evidence-Based Health Care, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa; 11Department of Health, Behavior and Society, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA; 12Department of Pediatrics and Child Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa; 13Department of Obstetrics and Gynecology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA; 14Department of Obstetrics and Gynecology, Faculty of Medicine and Health Sciences, Stellenbosch

  4. Distributed estimation based on observations prediction in wireless sensor networks

    KAUST Repository

    Bouchoucha, Taha

    2015-03-19

    We consider wireless sensor networks (WSNs) used for distributed estimation of unknown parameters. Due to the limited bandwidth, sensor nodes quantize their noisy observations before transmission to a fusion center (FC) for the estimation process. In this letter, the correlation between observations is exploited to reduce the mean-square error (MSE) of the distributed estimation. Specifically, sensor nodes generate local predictions of their observations and then transmit the quantized prediction errors (innovations) to the FC rather than the quantized observations. The analytic and numerical results show that transmitting the innovations rather than the observations mitigates the effect of quantization noise and hence reduces the MSE. © 2015 IEEE.

  5. Observationally based analysis of land-atmosphere coupling

    Science.gov (United States)

    Catalano, Franco; Alessandri, Andrea; De Felice, Matteo; Zhu, Zaichun; Myneni, Ranga B.

    2016-03-01

    The temporal variance of soil moisture, vegetation and evapotranspiration over land has been recognized to be strongly connected to the temporal variance of precipitation. However, the feedbacks and couplings between these variables are still not well understood and quantified. Furthermore, soil moisture and vegetation processes are associated with a memory and therefore they may have important implications for predictability. In this study we apply a generalized linear method, specifically designed to assess the reciprocal forcing between connected fields, to the latest available observational data sets of global precipitation, evapotranspiration, vegetation and soil moisture content. For the first time a long global observational data set is used to investigate the spatial and temporal land variability and to characterize the relationships and feedbacks between land and precipitation. The variables considered show a significant coupling among each other. The analysis of the response of precipitation to soil moisture evidences a robust coupling between these two variables. In particular, the first two modes of variability in the precipitation forced by soil moisture appear to have a strong link with volcanic eruptions and El Niño-Southern Oscillation (ENSO) cycles, respectively, and these links are modulated by the effects of evapotranspiration and vegetation. It is suggested that vegetation state and soil moisture provide a biophysical memory of ENSO and major volcanic eruptions, revealed through delayed feedbacks on rainfall patterns. The third mode of variability reveals a trend very similar to the trend of the inter-hemispheric contrast in sea surface temperature (SST) and appears to be connected to greening/browning trends of vegetation over the last three decades.

  6. Disturbance Observer Based Control of Multirotor Helicopters Based on a Universal Model with Unstructured Uncertainties

    Directory of Open Access Journals (Sweden)

    Ye Xie

    2015-01-01

    Full Text Available To handle different perspectives of unstructured uncertainties, two robust control techniques on the basis of a universal model are studied in this paper. Rather than building a model only applicable to a specific small-scale multirotor helicopter (MHeli, the paper proposes a modeling technique to develop a universal model-framework. Particularly, it is straightforward to apply the universal model to a certain MHeli because the contribution and allocation matrix is proposed in the model-framework. Based on the model uncertainties, the load perturbation of the rotor is the primary focus due to its indispensable importance in the tracking performance. In contrast to the common methods, it is proposed to take this unstructured uncertainty in that external disturbance and designs disturbance observer (DOB. In addition, a class of lead-compensator is specifically designed as for compensating phase lag induced by DOB. Compared with H∞ loop-shaping, greater robust tracking performance on rejecting load perturbation could be achieved as a tradeoff between robust stability and tracking performance which is successfully avoided with DOB-based control strategy.

  7. Agent Based Sensor and Data Fusion in Forest Fire Observer

    OpenAIRE

    &#;erić, Ljiljana; Stipani&#;ev, Darko; &#;tula, Maja

    2009-01-01

    Inspirited by the formal theory of perception and technology of sensor network we have introduced the idea of observer network as a reliable framework for data and information fusion. Our ideas have been successfully tested in the case of forest fire observer network. Observer network was implemented using multi-agent technology. A special multi agent shell was designed for this purpose having software system desirable features like modularity and flexibility. The system was implemented in nu...

  8. Observer-based quantum state estimation by continuous weak measurement

    CERN Document Server

    Leghtas, Zaki; Rouchon, Pierre

    2010-01-01

    We propose to apply the Back and Forth Nudging (BFN) method used for geophysical data assimilations to estimate the initial state of a quantum system. We consider a cloud of atoms interacting with a magnetic field while a single observable is being continuously measured over time using homodyne detection. The BFN method relies on designing an observer forward and backwards in time. The state of the BFN observer is continuously updated by the measured data and tends to converge to the system state. The proposed estimator seems to be globally asymptotically convergent when the system is observable. A detailed convergence proof and simulations are given in the 2-level case.

  9. Modeling Basin-scale Runoffs with Precipitation Data from Ground-based Observations and Mesoscale Simulations

    Science.gov (United States)

    Li, M.; Yang, M.; Soong, R.; Hwang, S.

    2002-12-01

    The purpose of this study is to investigate the applicability of distributed basin-scale runoff modeling, driven by rainfall data from either ground-based observations or mesoscale simulations, in response to typhoons invading Taiwan. Typhoons Herb (1996) and Zeb (1998) were selected for calibrating the runoff parameters reflecting the landuse conditions in the basin and evaluating the applicability of observed and simulated rainfall data toward runoff estimations, respectively. Upstream basins of Reservoir Shihmen with a drainage area of 764 km2 and Reservoir Feitsui with a drainage area of 303 km2 were the domains of interest in this preliminary study. Ground-based observations of both stream flows and station rainfalls were collected in an hourly resolution. The mesoscale model,MM5, simulation for Herb was conducted in 4-nested grids with the finest resolution of 2.2 km and 2-nested grids with the finest resolution of 15 km for Zeb, and the time resolution for both cases was 5 minutes. Accumulated total rain was accommodated with terrain elevation in MM5 simulations and station data to provide areal rainfall distributions. While the ground-based observations were sparse and incapable of correctly representing areal rainfall characteristics, the MM5 simulated data may introduce great uncertainties in basin-scale hydrological applications. The experience learned from this study is expected to provide an applicable approach with both ground-based observations and mesoscale simulations in basin-scale runoff computations.

  10. An Observational Study of Algol-Type Binary System

    Science.gov (United States)

    Zhang, J.

    2015-01-01

    The Algol-Type binary systems are a subtype of binary systems. Their unique semi-detached structure leads to have abundant physical phenomena, including the dramatically distorted donor star, strong magnetic activities, various ways of mass transfer, the evolution stage quite different from that of single stars, and specific formation tracks. In this paper, we introduce the fundamental physics of light curves, as well as the models or programs used in the past. We show the influence of different parameters on the light curves, including the inclination, temperature, abundance, surface gravity, the third light, radius, orbital eccentricity, and the argument of periastron. Based on the current catalog of Algols, we investigate their statistic characteristics. We observe three Algols and analyze the data in detail. The results are as follows: (1)Our statistical analyses of Algols support the previous suggestion that most of the detached component stars are main sequence stars. The distribution of the mass ratio agrees to our calculated critical value of the mass ratio for Algols. We suggest that there could be a lower limit of the radius ratio. We also show that there are good correlations among the temperature, luminosity, radius, and the mass of the component stars. (2) The binary FG Gem is observed, and the data are analyzed. Based on the solutions of large combinations of the temperature and luminosity, we use a new age-comparing method to show that the FG Gem is a semi-detached system, and a new temperature-searching method to get a better estimate of the temperature of the detached component star. We suggest that a combination of the intermittent mass flow and the continuous magnetic braking can explain its orbital period change. (3) Taking the VV Vir as an example, we discuss some properties of the mass flow in a semi-detached binary. Some of them can reflect the common characteristics of the mass flows in the Algol systems, e.g., the radius of the mass flow is

  11. Grid-based platform for training in Earth Observation

    Science.gov (United States)

    Petcu, Dana; Zaharie, Daniela; Panica, Silviu; Frincu, Marc; Neagul, Marian; Gorgan, Dorian; Stefanut, Teodor

    2010-05-01

    GiSHEO platform [1] providing on-demand services for training and high education in Earth Observation is developed, in the frame of an ESA funded project through its PECS programme, to respond to the needs of powerful education resources in remote sensing field. It intends to be a Grid-based platform of which potential for experimentation and extensibility are the key benefits compared with a desktop software solution. Near-real time applications requiring simultaneous multiple short-time-response data-intensive tasks, as in the case of a short time training event, are the ones that are proved to be ideal for this platform. The platform is based on Globus Toolkit 4 facilities for security and process management, and on the clusters of four academic institutions involved in the project. The authorization uses a VOMS service. The main public services are the followings: the EO processing services (represented through special WSRF-type services); the workflow service exposing a particular workflow engine; the data indexing and discovery service for accessing the data management mechanisms; the processing services, a collection allowing easy access to the processing platform. The WSRF-type services for basic satellite image processing are reusing free image processing tools, OpenCV and GDAL. New algorithms and workflows were develop to tackle with challenging problems like detecting the underground remains of old fortifications, walls or houses. More details can be found in [2]. Composed services can be specified through workflows and are easy to be deployed. The workflow engine, OSyRIS (Orchestration System using a Rule based Inference Solution), is based on DROOLS, and a new rule-based workflow language, SILK (SImple Language for worKflow), has been built. Workflow creation in SILK can be done with or without a visual designing tools. The basics of SILK are the tasks and relations (rules) between them. It is similar with the SCUFL language, but not relying on XML in

  12. Study of white-light flares observed by Hinode

    Institute of Scientific and Technical Information of China (English)

    Hai-Min Wang

    2009-01-01

    White-light flares are considered to be the most energetic flaring events that are observable in the optical broad-band continuum of the solar spectrum. They have not been commonly observed. Observations of white-light flares with sub-arcsecond resolution have been very rare. The continuous high resolution observations of Hinode provide a unique opportunity to systematically study the white-light flares with a spatial resolution around 0.2 arcsec. We surveyed all the flares above GOES magnitude C5.0 since the launch of Hinode in 2006 October. 13 of these kinds of flares were covered by the Hinode G-band observations. We analyzed the peak contrasts and equivalent areas (calculated via integrated excess emission contrast) of these flares as a function of the GOES X-ray flux, and found that the cut-off visibility is likely around M1 flares under the observing limit of Hinode. Many other observational and physical factors should affect the visibility of white-light flares; as the observing conditions are improved, smaller flares are likely to have detectable white-light emissions. We are cautious that this limiting visibility is an overestimate, because G-band observations contain emissions from the upper atmosphere.Among the 13 events analyzed, only the M8.7 flare of 2007 June 4 had near-simultaneous observations in both the G-band and the blue continuum. The blue continuum had a peak contrast of 94% vs. 175% in G-band for this event. The equivalent area in the blue continuum is an order of magnitude lower than that in the G-band. Very recently, Jess et al.studied a C2.0 flare with a peak contrast of 300% in the blue continuum. Compared to the events presented in this letter, that event is probably an unusual white-light flare: a very small kernel with a large contrast that can be detected in high resolution observations.

  13. Scientific and Ethical Approaches for Observational Exposure Studies

    Science.gov (United States)

    Researchers conduct observational human exposure studies to understand how and the extent to which people come into contact with chemicals and environmental stressors in their everyday lives, through the air they breathe, the food and liquids they consume, and the things they tou...

  14. Observational Studies of Retarded Children with Multiple Stereotyped Movements.

    Science.gov (United States)

    Baumeister, Alfred A.; And Others

    1980-01-01

    Three relatively long-term observational studies, involving seven retarded preschool children, each of whom exhibited multiple stereotypes, were conducted to determine the extent to which the type of activity or setting had any effect upon the rates of stereotyped movements. (Author)

  15. Protopathic bias in observational studies on statin effectiveness

    OpenAIRE

    Korhonen, Maarit Jaana; Huupponen, Risto; Ruokoniemi, Päivi; Helin-Salmivaara, Arja

    2009-01-01

    Protopathic bias in observational studies on statin effectiveness phone: +350-40-3552901 (Korhonen, Maarit Jaana) (Korhonen, Maarit Jaana) Pharmacology, Drug Development and Therapeutics, University of Turku - 20014 - Turku - FINLAND (Korhonen, Maarit Jaana) School of Public Health and Clinical Nutrition, University of Kuopio - POB 1627 - 70211 - Kuopio - FINLAND (Korhonen, Maarit Jaana) Pharmacology, Drug Development and Therapeutics, University of T...

  16. The East Madagascar Current: Volume Transport and Variability Based on Long-Term Observations

    NARCIS (Netherlands)

    Ponsoni, L.; Aguiar-González, B.; Ridderinkhof, H.; Maas, L.

    2016-01-01

    This study provides a long-term description of the poleward East Madagascar Current (EMC) in terms of its observed velocities, estimated volume transport, and variability based on both ~2.5 yr of continuous in situ measurements and ~21 yr of satellite altimeter data. An array of five moorings was de

  17. Methodological issues in observational studies of obesity and mortality

    OpenAIRE

    W. Dana Flanders; Liv Berit Augestad

    2011-01-01

    Obesity has important health hazards, and the epidemic seems to be growing in developed countries. There is scientific evidence for higher risk of earlier death among the obese. However, most evidence of the effects of obesity on mortality comes from observational studies. The aim of this manuscript is to reviewsome of the most important issues in designing, analyzing and interpreting analytic studies of the effects of obesity on mortality. Key issues are clarity in the definition of the effe...

  18. Observational studies of transiting extrasolar planets (invited review)

    OpenAIRE

    Southworth, J.

    2014-01-01

    The study of transiting extrasolar planets is only 15 years old, but has matured into a rich area of research. I review the observational aspects of this work, concentrating on the discovery of transits, the characterisation of planets from photometry and spectroscopy, the Homogeneous Studies project, starspots, orbital obliquities, and the atmospheric properties of the known planets. I begin with historical context and conclude with a glance to a future of TESS, CHEOPS, Gaia and PLATO.

  19. Cauchy problem for Laplace equation: An observer based approach

    KAUST Repository

    Majeed, Muhammad Usman

    2013-10-01

    A method to solve Cauchy Problem for Laplace equation using state observers is proposed. It is known that this problem is ill-posed. The domain under consideration is simple lipschitz in 2 with a hole. The idea is to recover the solution over whole domain from the observations on outer boundary. Proposed approach adapts one of the space variables as a time variable. The observer developed to solve Cauchy problem for the Laplace\\'s equation is compuationally robust and accurate. © 2013 IEEE.

  20. Two-stage observer based offset-free MPC.

    Science.gov (United States)

    Mohammadkhani, MohammadAli; Bayat, Farhad; Jalali, Ali Akbar

    2015-07-01

    This paper addresses design of model predictive control (MPC) for dynamic systems in the presence of disturbances. For the systems with disturbances, it is common to use observers to estimate states and disturbances, allowing control algorithm to reject disturbances. In this paper, we demonstrate how one can extend model predictive control for systems with disturbances by applying full state and disturbance observer. To this aim, a two-stage approach is proposed where the observer design procedure is completely decoupled from the MPC problem, known as the separation principle. We focus on the decoupling principal and it is shown that the observer can be designed independently via a norm minimization problem to reduce effects of disturbances and model mismatch. On the other hand, the MPC law is obtained using the multi-parametric quadratic programming approach where the parameters are the components of the state vector. PMID:25820088

  1. Study of phyllosilicates and carbonates from the Capri Chasma region of Valles Marineris on Mars based on Mars Reconnaissance Orbiter-Compact Reconnaissance Imaging Spectrometer for Mars (MRO-CRISM) observations

    Science.gov (United States)

    Jain, Nirmala; Chauhan, Prakash

    2015-04-01

    Spectral reflectance data from the MRO-CRISM (Mars Reconnaissance Orbiter-Compact Reconnaissance Imaging Spectrometer for Mars) of Capri Chasma, a large canyon within Valles Marineris on Mars, have been studied. Results of this analysis reveal the presence of minerals, such as, phyllosilicates (illite, smectite (montmorillonite)) and carbonates (ankerite and manganocalcite). These minerals hint of the aqueous history of Noachian time on Mars. Phyllosilicates are products of chemical weathering of igneous rocks, whereas carbonates could have formed from local aqueous alteration of olivine and other igneous minerals. Four different locations within the Capri Chasma region were studied for spectral reflectance based mineral detection. The study area also shows the spectral signatures of iron-bearing minerals, e.g. olivine with carbonate, indicating partial weathering of parent rocks primarily rich in ferrous mineral. The present study shows that the minerals of Capri Chasma are characterized by the presence of prominent spectral absorption features at 2.31 μm, 2.33 μm, 2.22 μm, 2.48 μm and 2.52 μm wavelength regions, indicating the existence of hydrous minerals, i.e., carbonates and phyllosilicates. The occurrence of carbonates and phyllosilicates in the study area suggests the presence of alkaline environment during the period of their formation. Results of the study are important to understand the formation processes of these mineral assemblages on Mars, which may help in understanding the evolutionary history of the planet.

  2. Information-Based Physics: An Observer-Centric Foundation

    OpenAIRE

    Knuth, Kevin H.

    2013-01-01

    It is generally believed that physical laws, reflecting an inherent order in the universe, are ordained by nature. However, in modern physics the observer plays a central role raising questions about how an observer-centric physics can result in laws apparently worthy of a universal nature-centric physics. Over the last decade, we have found that the consistent apt quantification of algebraic and order-theoretic structures results in calculi that possess constraint equations taking the form o...

  3. Towards observation based gridded runoff estimates for Europe

    OpenAIRE

    L. Gudmundsson; S. I. Seneviratne

    2014-01-01

    Terrestrial water variables are the key to understanding ecosystem processes, feed back on weather and climate, and are a prerequisite for human activities. To provide context for local investigations and to better understand phenomena that only emerge at large spatial scales, reliable information on continental scale freshwater dynamics is necessary. To date streamflow is among the best observed variables of terrestrial water systems. However, observation n...

  4. Towards observation-based gridded runoff estimates for Europe

    OpenAIRE

    L. Gudmundsson; S. I. Seneviratne

    2015-01-01

    Terrestrial water variables are the key to understanding ecosystem processes, feed back on weather and climate, and are a prerequisite for human activities. To provide context for local investigations and to better understand phenomena that only emerge at large spatial scales, reliable information on continental-scale freshwater dynamics is necessary. To date streamflow is among the best-observed variables of terrestrial water systems. However, observation networks have a ...

  5. Carbon Dioxide Observational Platform System (CO-OPS), feasibility study

    Science.gov (United States)

    Bouquet, D. L.; Hall, D. W.; Mcelveen, R. P.

    1987-01-01

    The Carbon Dioxide Observational Platform System (CO-OPS) is a near-space, geostationary, multi-user, unmanned microwave powered monitoring platform system. This systems engineering feasibility study addressed identified existing requirements such as: carbon dioxide observational data requirements, communications requirements, and eye-in-the-sky requirements of other groups like the Defense Department, the Forestry Service, and the Coast Guard. In addition, potential applications in: earth system science, space system sciences, and test and verification (satellite sensors and data management techniques) were considered. The eleven month effort is summarized. Past work and methods of gathering the required observational data were assessed and rough-order-of magnitude cost estimates have shown the CO-OPS system to be most cost effective (less than $30 million within a 10 year lifetime). It was also concluded that there are no technical, schedule, or obstacles that would prevent achieving the objectives of the total 5-year CO-OPS program.

  6. A rule-based shell to hierarchically organize HST observations

    Science.gov (United States)

    Bose, Ashim; Gerb, Andrew

    1995-01-01

    An observing program on the Hubble Space Telescope (HST) is described in terms of exposures that are obtained by one or more of the instruments onboard the HST. These exposures are organized into a hierarchy of structures for purposes of efficient scheduling of observations. The process by which exposures get organized into the higher-level structures is called merging. This process relies on rules to determine which observations can be 'merged' into the same higher level structure, and which cannot. The TRANSformation expert system converts proposals for astronomical observations with HST into detailed observing plans. The conversion process includes the task of merging. Within TRANS, we have implemented a declarative shell to facilitate merging. This shell offers the following features: (1) an easy way of specifying rules on when to merge and when not to merge, (2) a straightforward priority mechanism for resolving conflicts among rules, (3) an explanation facility for recording the merging history, (4) a report generating mechanism to help users understand the reasons for merging, and (5) a self-documenting mechanism that documents all the merging rules that have been defined in the shell, ordered by priority. The merging shell is implemented using an object-oriented paradigm in CLOS. It has been a part of operational TRANS (after extensive testing) since July 1993. It has fulfilled all performance expectations, and has considerably simplified the process of implementing new or changed requirements for merging. The users are pleased with its report-generating and self-documenting features.

  7. First ground-based FTIR observations of the seasonal variation of carbon monoxide in the tropics

    Science.gov (United States)

    Petersen, A. K.; Warneke, T.; Lawrence, M. G.; Notholt, J.; Schrems, O.

    2008-02-01

    We present the first ground-based solar absorption Fourier Transform Infrared (FTIR) spectrometric measurements in the inner tropics over several years. The FTIR observations agree well with satellite data from the MOPITT instrument. MATCH-MPIC model simulations reproduce the mean vertical structure of the FTIR observations. The model is generally not able to reproduce the extreme enhancements seen during the specific biomass burning events by both observation instruments. Nevertheless, the model indicates that beyond the background source of CO from methane oxidation, the main contributions to the CO mixing ratios are the episodic convective injection of NMHCs and CO from South American biomass burning into the upper troposphere, along with long range transport of African biomass burning CO, particularly during spring. In future studies with more extensive observed time series, observations such as these will be valuable for evaluating ongoing improvements in global chemistry transport models.

  8. Reflective Practice Through Journal Writing 
And Peer Observation: A Case Study

    OpenAIRE

    B. Samrajya LAKSHMI

    2014-01-01

    Journal writing and Peer Observation in an educational context have become popular techniques, with several different types of applications. They have now been used quite widely in both language teaching and in teacher training. However, despite its reported advantages in both teaching and research, there are not many Peer Observation and Diary studies available based on the writing of experienced language teachers. The Teacher participants maintain Journal writing and Peer Observation as a m...

  9. Ground-based observations of Kepler asteroseismic targets

    DEFF Research Database (Denmark)

    Uyttterhoeven , K.; Karoff, Christoffer

    We present the ground-based activities within the different working groups of the Kepler Asteroseismic Science Consortium (KASC). The activities aim at the systematic characterization of the 5000+ KASC targets, and at the collection of ground-based follow-up time-series data of selected promising...

  10. Observations of the Geometry of Horizon-Based Optical Navigation

    Science.gov (United States)

    Christian, John; Robinson, Shane

    2016-01-01

    NASA's Orion Project has sparked a renewed interest in horizon-based optical navigation(OPNAV) techniques for spacecraft in the Earth-Moon system. Some approaches have begun to explore the geometry of horizon-based OPNAV and exploit the fact that it is a conic section problem. Therefore, the present paper focuses more deeply on understanding and leveraging the various geometric interpretations of horizon-based OPNAV. These results provide valuable insight into the fundamental workings of OPNAV solution methods, their convergence properties, and associated estimate covariance. Most importantly, the geometry and transformations uncovered in this paper lead to a simple and non-iterative solution to the generic horizon-based OPNAV problem. This represents a significant theoretical advancement over existing methods. Thus, we find that a clear understanding of geometric relationships is central to the prudent design, use, and operation of horizon-based OPNAV techniques.

  11. Diffusion-Based Trajectory Observers with Variance Constraints

    DEFF Research Database (Denmark)

    Alcocer, Alex; Jouffroy, Jerome; Oliveira, Paulo;

    level of smoothing and is determined by resorting to trial and error. This paper presents a methodology to choose the observer gain by taking into account a priori information on the variance of the position measurement errors. Experimental results with data from an acoustic positioning system are...

  12. Unsteady aerodynamic modeling based on POD-observer method

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A new hybrid approach to constructing reduced-order models(ROM)of unsteady aerodynamics applicable to aeroelastic analysis is presented by using proper orthogonal decomposition(POD)in combination with observer techniques.Fluid modes are generated through POD by sampling observations of solutions derived from the full-order model.The response in the POD training is projected onto the fluid modes to determine the time history of the modal amplitudes.The resulting data are used to extract the Markov parameters of the low-dimensional model for modal amplitudes using a related deadbeat observer.The state-space realization is synthesized from the system’s Markov parameters that are processed with the eigensystem realization algorithm.The POD-observer method is applied to a two-dimensional airfoil system in subsonic flow field.The results predicted by the ROM are in general agreement with those from the full-order system.The ROM obtained by the hybrid approach captures the essence of a fluid system and produces vast reduction in both degrees of freedom and computational time relative to the full-order model.

  13. CHATURBEEJA IN PRIMARY DYSMENORRHOEA (KASHTARTAVA: AN OBSERVATIONAL STUDY

    Directory of Open Access Journals (Sweden)

    Dhiman Kamini

    2012-06-01

    Full Text Available In folk medicines, Chaturbeeja(combination of seeds of four plants i.e Trigonella Foenum-graecum, Lepidium sativum , Nigella sativa, Trachyspermum ammi in equal quantity has been traditionally used for variety of applications including treatment of Dysmenorrhoea, the most common gynaecological symptom reported by women. To promote the proper use of such medicines and to determine their potential as sources for new drugs, it is essential to study medicinal plants, which have folklore reputation in a more intensified way. A Single blind, prospective observational clinical study was conducted to evaluate the efficacy of Chaturbeeja powder in Primary Dysmenorrhoea (Kashtartava. 25 patients were administered Chaturbeeja powder in a single dose of 3g with hot water at night, 7 days before starting of menstruation till 3rd day of the menstruation cycle. After assessing the results it was observed that12 patients were markedly improved, 8 moderately improved and 5 were improved.

  14. Meditation Based Therapies—A Systematic Review and Some Critical Observations

    DEFF Research Database (Denmark)

    Fjorback, Lone; Walach, Harald

    2012-01-01

    This article systematically reviews the evidence for Mindfulness-Based Stress Reduction (MBSR) and Mindfulness-Based Cognitive Therapy (MBCT) and analyses the conditions around their rising popularity. MBSR, MBCT and Mindfulness Meditation were used as key words. The inclusion criteria were...... randomized controlled trials using the standard MBSR/MBCT program with a minimum of 33 participants. Twenty four studies were included. MBSR improved mental health in ten studies compared to waitlist control or treatment as usual. Moreover, MBSR was as efficacious as active control group in four studies, and...... showed a tendency over active control in one study. MBCT reduced the risk of depressive relapse in all five included studies. Evidence supports that MBSR improves mental health and MBCT prevents depressive relapse. It is interesting to observe that meditation based therapy programs are rapidly enjoying...

  15. Meditation Based Therapies—A Systematic Review and Some Critical Observations

    Directory of Open Access Journals (Sweden)

    Lone Overby Fjorback

    2012-01-01

    Full Text Available This article systematically reviews the evidence for Mindfulness-Based Stress Reduction (MBSR and Mindfulness-Based Cognitive Therapy (MBCT and analyses the conditions around their rising popularity. MBSR, MBCT and Mindfulness Meditation were used as key words. The inclusion criteria were randomized controlled trials using the standard MBSR/MBCT program with a minimum of 33 participants. Twenty four studies were included. MBSR improved mental health in ten studies compared to waitlist control or treatment as usual. Moreover, MBSR was as efficacious as active control group in four studies, and showed a tendency over active control in one study. MBCT reduced the risk of depressive relapse in all five included studies. Evidence supports that MBSR improves mental health and MBCT prevents depressive relapse. It is interesting to observe that meditation based therapy programs are rapidly enjoying popularity. We discuss the cultural and theoretical implications.

  16. Evidence-Based Novel Changes in Prevalence and Symptom Characteristics of Spleen Deficiency Syndrome in Persons of Varied Health Status and Different Ages: A Cross-Sectional Observational Study

    Directory of Open Access Journals (Sweden)

    Yin Zhang

    2014-01-01

    Full Text Available Deficiency of the organs is a vital pathophysiologic characteristic in the elderly. A core TCM aging theory is known as aging caused by spleen deficiency syndrome (SDS that can be found in ancient and modern literature. The key objectives of this study were to establish a full-scale trial to evaluate the prevalence, symptom severity, frequency, and distribution of SDS in different age groups as related to health status (healthy, subhealthy, and chronic disease to elucidate the role of spleen deficiency in the aging process and deterioration of health status. This cross-sectional observational study was conducted in 4 hospitals in China. 1390 participants aged 20–79 were interviewed by investigators who completed questionnaires recording prevalence, severity, and frequency of symptoms as well as other relevant information. The results revealed that prevalence and symptom characteristics of SDS showed regularities with increasing age and deteriorating health status. It supports the TCM concept that spleen deficiency is an important mechanism of aging, subhealth, and chronic diseases. Early recognition of the warning signs and symptoms of SDS may lead to intervention and even prevention strategies for subhealth and chronic diseases as well as promotion of healthy aging.

  17. Effective population management practices in diabetes care - an observational study

    DEFF Research Database (Denmark)

    Frølich, Anne; Bellows, Jim; Nielsen, Bo Friis;

    2010-01-01

    Of fifteen diabetes care management practices, our data indicate that high performance is most associated with provider alerts and more weakly associated with action plans and with guideline distribution and training. Lack of convergence in the literature on effective care management practices...... suggests that factors contributing to high performance may be highly context-dependent or that the factors involved may be too numerous or their implementation too nuanced to be reliably identified in observational studies....

  18. Patient satisfaction concerning implant-supported prostheses: an observational study

    OpenAIRE

    Bruno César de Vasconcelos GURGEL; Ana Luísa de Barros PASCOAL; Bruno Luiz Menezes de SOUZA; Poliana Medeiros Cunha DANTAS; Sheyla Christinne Lira MONTENEGRO; Angelo Giuseppe Roncalli da Costa OLIVEIRA; Calderon, Patrícia dos Santos

    2015-01-01

    The aim of this observational study was to assess the degree of patient satisfaction toward implant-supported prostheses. A questionnaire was used with two scales (one consisting of detailed adjectival and the other of numerical responses) regarding chewing, esthetics, speaking, comfort and overall satisfaction. The scales were administered to a sample of 147 patients treated with implants and prostheses. The data were submitted to the Kappa statistic and the Chi-square test to analyze the as...

  19. Comparative Studies of Different Imputation Methods for Recovering Streamflow Observation

    OpenAIRE

    Kim, Minjeong; Baek, Sangsoo; Ligaray, Mayzonee; Pyo, Jongcheol; Park, Minji; Cho, Kyung

    2015-01-01

    Faulty field sensors cause unreliability in the observed data that needed to calibrate and assess hydrology models. However, it is illogical to ignore abnormal or missing values if there are limited data available. This study addressed this problem by applying data imputation to replace incorrect values and recover missing streamflow information in the dataset of the Samho gauging station at Taehwa River (TR), Korea from 2004 to 2006. Soil and Water Assessment Tool (SWAT) and two machine lear...

  20. Conceptual Research of Lunar-based Earth Observation for Polar Glacier Motion

    Science.gov (United States)

    Ruan, Zhixing; Liu, Guang; Ding, Yixing

    2016-07-01

    The ice flow velocity of glaciers is important for estimating the polar ice sheet mass balance, and it is of great significance for studies into rising sea level under the background of global warming. However so far the long-term and global measurements of these macro-scale motion processes of the polar glaciers have hardly been achieved by Earth Observation (EO) technique from the ground, aircraft or satellites in space. This paper, facing the demand for space technology for large-scale global environmental change observation,especially the changes of polar glaciers, and proposes a new concept involving setting up sensors on the lunar surface and using the Moon as a platform for Earth observation, transmitting the data back to Earth. Lunar-based Earth observation, which enables the Earth's large-scale, continuous, long-term dynamic motions to be measured, is expected to provide a new solution to the problems mentioned above. According to the pattern and characteristics of polar glaciers motion, we will propose a comprehensive investigation of Lunar-based Earth observation with synthetic aperture radar (SAR). Via theoretical modeling and experimental simulation inversion, intensive studies of Lunar-based Earth observation for the glacier motions in the polar regions will be implemented, including the InSAR basics theory, observation modes of InSAR and optimization methods of their key parameters. It will be of a great help to creatively expand the EO technique system from space. In addition, they will contribute to establishing the theoretical foundation for the realization of the global, long-term and continuous observation for the glacier motion phenomena in the Antarctic and the Arctic.

  1. Observer based output feedback tuning for underwater remotely operated vehicle based on linear quadratic performance

    Science.gov (United States)

    Aras, Mohd Shahrieel Mohd; Abdullah, Shahrum Shah; Kamarudin, Muhammad Nizam; Rahman, Ahmad Fadzli Nizam Abdul; Azis, Fadilah Abd; Jaafar, Hazriq Izzuan

    2015-05-01

    This paper describes the effectiveness of observer-based output feedback for Unmanned Underwater Vehicle (UUV) with Linear Quadratic Regulation (LQR) performance. Tuning of observer parameters is crucial for tracking purpose. Prior to tuning facility, the ranges of observer and LQR parameters are obtained via system output cum error. The validation of this technique using unmanned underwater vehicles called Remotely Operated Vehicle (ROV) modelling helps to improve steady state performance of system response. The ROV modeling is focused for depth control using ROV 1 developed by the Underwater Technology Research Group (UTeRG). The results are showing that this technique improves steady state performances in term of overshoot and settling time of the system response.

  2. Observational cohort study of HIV-infected African children.

    NARCIS (Netherlands)

    Laufer, M.K.; Oosterhout, J.J. van; Perez, M.A.; Kanyanganlika, J.; Taylor, T.E.; Plowe, C.V.; Graham, S.M.

    2006-01-01

    BACKGROUND: Most information about children living with HIV is based on follow up from children identified through mother-to-child transmission studies. Children identified through voluntary counseling and testing (VCT) represent a unique cohort that has not been previously described in the literatu

  3. Observer based estimation in heterologous protein production by Pichia pastoris

    OpenAIRE

    Barrigón, J. M.; Rocha, I.; F. Valero; Ferreira, E. C.; Montesinos, J. L.

    2010-01-01

    The methylotrophic yeast Pichia pastoris has been widely reported as a suitable expression system for both basic research and industrial use. In order to achieve high productivity, constant product quality, as well as to allow optimization and control of biotechnological processes, real-time monitoring of the key fermentation variables (biomass, substrate and products) is of major academic and industrial relevance. In this work, asymptotic observers (AO) have been designed for the estima...

  4. Robust vehicle steering control design based on the disturbance observer

    OpenAIRE

    Bünte, T.; Odenthal, D.; Aksun-Güvenc, B.; Güvenc, L.

    2001-01-01

    A robust steering controller is introduced for improving the yaw dynamics of a passenger car. A specific two degree of freedom control architecture known as the disturbance observer is adapted to the vehicle yaw dynamics control problem and shown to robustly improve performance. The relevant design specifications are formulated in terms of eigenvalues (T-stability) and in frequency domain as bounds on weighted sensitivity and complementary sensitivity functions (B-stability). The parameter sp...

  5. Singular Vector Based Targeted Observations of Atmospheric Chemical Compounds

    OpenAIRE

    Goris, Nadine

    2010-01-01

    Measurements of the earth's environment provide only sparse snapshots of the state of the system due to their insufficient temporal and spatial density. In face of these limitations, the measurement configurations need to be optimized to get a best possible state estimate. One possibility to optimize the state estimate is provided by targeted observations of sensitive system states, where measurements are of great value for forecast improvements. In the recent years, numerical weather predict...

  6. Using Copulas in Data Mining Based on the Observational Calculus

    Czech Academy of Sciences Publication Activity Database

    Holeňa, Martin; Bajer, L.; Ščavnický, M.

    2015-01-01

    Roč. 27, č. 10 (2015), s. 2851-2864. ISSN 1041-4347 R&D Projects: GA ČR GA13-17187S Grant ostatní: SLU(CZ) SGS/21/2014 Institutional support: RVO:67985807 Keywords : data mining * observational calculus * generalized quantifiers * joint probability distribution * copulas * hierarchical Archimedean copulas Subject RIV: IN - Informatics, Computer Science Impact factor: 2.067, year: 2014

  7. Study of some defects observed in the hexagonal liquid crystals

    International Nuclear Information System (INIS)

    A polarising microscopy study of the disclinations in an hexagonal discotic liquid crystal (hexa-pentoxy-triphenylene) allows us to confirm the theory of the developable domains and the existence of the disclinations as involute of the circle. The absence of the lines S = 1 leads us to propose a model of core in which the energetic instability of these lines is emphasized. The nature of the core is discussed: it is probably filled with hexagonal liquid crystal. Moreover the birefringence Δn is measured and a first estimate of the anchoring energies of the discotic both on the glass and in contact with the air is given. The Michelson interferometry study of the interaction between the disclinations and the free surface has allowed to observe a strong anisotropy of the interfacial tension. At last a study of the walls leads to a classification according to the matching angle and to a first estimate of the penetration distance λ. A similar study has been undertaken in an inverse middle liquid crystalline phase (Na dioctylsulfosuccinate). A strong dependence of the elastic constants with the water concentration is observed. The micellar → hexagonal transition is studied. (author)

  8. Acceptability and feasibility of mHealth and community-based directly observed antiretroviral therapy to prevent mother-to-child HIV transmission in South African pregnant women under Option B+: an exploratory study

    Science.gov (United States)

    Nachega, Jean B; Skinner, Donald; Jennings, Larissa; Magidson, Jessica F; Altice, Frederick L; Burke, Jessica G; Lester, Richard T; Uthman, Olalekan A; Knowlton, Amy R; Cotton, Mark F; Anderson, Jean R; Theron, Gerhard B

    2016-01-01

    Objective To examine the acceptability and feasibility of mobile health (mHealth)/short message service (SMS) and community-based directly observed antiretroviral therapy (cDOT) as interventions to improve antiretroviral therapy (ART) adherence for preventing mother-to-child human immunodeficiency virus (HIV) transmission (PMTCT). Design and methods A mixed-method approach was used. Two qualitative focus group discussions with HIV-infected pregnant women (n=20) examined the acceptability and feasibility of two ART adherence interventions for PMTCT: 1) SMS text messaging and 2) patient-nominated cDOT supporters. Additionally, 109 HIV-infected, pregnant South African women (18–30 years old) receiving PMTCT services under single-tablet antiretroviral therapy regimen during pregnancy and breastfeeding and continuing for life (“Option B+”) were interviewed about mobile phone access, SMS use, and potential treatment supporters. Setting A community primary care clinic in Cape Town, South Africa. Participants HIV-infected pregnant women. Main outcomes Acceptability and feasibility of mHealth and cDOT interventions. Results Among the 109 women interviewed, individual mobile phone access and SMS use were high (>90%), and 88.1% of women were interested in receiving SMS ART adherence support messages such as reminders, motivation, and medication updates. Nearly all women (95%) identified at least one person close to them to whom they had disclosed their HIV status and would nominate as a cDOT supporter. Focus group discussions revealed that cDOT supporters and adherence text messages were valued, but some concerns regarding supporter time availability and risk of unintended HIV status disclosure were expressed. Conclusion mHealth and/or cDOT supporter as interventions to improve ART adherence are feasible in this setting. However, safe HIV status disclosure to treatment supporters and confidentiality of text messaging content about HIV and ART were deemed crucial. PMID

  9. Space-Based Gravitational-Wave Observations as Tools for Testing General Relativity

    Science.gov (United States)

    Will, Clifford M.

    2004-01-01

    We continued a project, to analyse the ways in which detection and study of gravitational waves could provide quantitative tests of general relativity, with particular emphasis on waves that would be detectable by space-based observatories, such as LISA. This work had three foci: 1) Tests of scalar-tensor theories of gravity that, could be done by analyzing gravitational waves from neutron stars inspiralling into massive black holes, as detectable by LISA; 2) Study of alternative theories of gravity in which the graviton could be massive, and of how gravitational-wave observations by space-based detectors, solar-system tests, and cosmological observations could constrain such theories; and 3) Study of gravitational-radiation back reaction of particles orbiting black holes in general relativity, with emphasis on the effects of spin.

  10. A LEKID-based CMB instrument design for large-scale observations in Greenland

    Science.gov (United States)

    Araujo, D. C.; Ade, P. A. R.; Bond, J. R.; Bradford, K. J.; Chapman, D.; Che, G.; Day, P. K.; Didier, J.; Doyle, S.; Eriksen, H. K.; Flanigan, D.; Groppi, C. E.; Hillbrand, Seth N.; Johnson, B. R.; Jones, G.; Limon, Michele; Miller, A. D.; Mauskopf, P.; McCarrick, H.; Mroczkowski, T.; Reichborn-Kjennerud, B.; Smiley, B.; Sobrin, Joshua; Wehus, I. K.; Zmuidzinas, J.

    2014-08-01

    We present the results of a feasibility study, which examined deployment of a ground-based millimeter-wave polarimeter, tailored for observing the cosmic microwave background (CMB), to Isi Station in Greenland. The instrument for this study is based on lumped-element kinetic inductance detectors (LEKIDs) and an F/2.4 catoptric, crossed-Dragone telescope with a 500 mm aperture. The telescope is mounted inside the receiver and cooled to shaft motor based on a superconducting magnetic bearing. The modular detector array design includes at least 2300 LEKIDs, and it can be configured for spectral bands centered on 150 GHz or greater. Our study considered configurations for observing in spectral bands centered on 150, 210 and 267 GHz. The entire polarimeter is mounted on a commercial precision rotary air bearing, which allows fast azimuth scan speeds with negligible vibration and mechanical wear over time. A slip ring provides power to the instrument, enabling circular scans (360 degrees of continuous rotation). This mount, when combined with sky rotation and the latitude of the observation site, produces a hypotrochoid scan pattern, which yields excellent cross-linking and enables 34% of the sky to be observed using a range of constant elevation scans. This scan pattern and sky coverage combined with the beam size (15 arcmin at 150 GHz) makes the instrument sensitive to 5 < ` < 1000 in the angular power spectra.

  11. The ground-based solar observations database BASS 2000

    OpenAIRE

    Paletou, F; Lafon, M.; Maeght, P.; Grimaud, F.; Louge, T.; Aboudarham, J.

    2007-01-01

    BASS 2000 is the French solar database for ground-based instruments. We describe hereafter our organization, our tasks and the products we can deliver to the international community. Our prospects cover data mining into the THeMIS archive, a participation to the EST endeavour and the creation and curation of the ESPaDOnS/NARVAL stellar spectra database.

  12. Observations on Experience and Flow in Movement-Based Interaction

    NARCIS (Netherlands)

    Nijholt, Anton; Pasch, Marco; Dijk, van Betsy; Reidsma, Dennis; Heylen, Dirk; England, David

    2011-01-01

    Movement-based interfaces assume that their users move. Users have to perform exercises, they have to dance, they have to golf or football, or they want to train particular bodily skills. Many examples of those interfaces exist, sometimes asking for subtle interaction between user and interface and

  13. Application of Copulas to Data Mining Based on Observational Logic

    Czech Academy of Sciences Publication Activity Database

    Holeňa, Martin; Ščavnický, M.

    North Charleston: CreateSpace Independent Publishing Platform, 2013 - (Vinař, T.; Holeňa, M.; Lexa, M.; Peška, L.; Vojtáš, P.), s. 77-85 ISBN 978-1-4909-5208-6. [ITAT 2013. Conference on Theory and Practice of Information Technologies. Donovaly (SK), 11.09.2013-15.09.2013] R&D Projects: GA ČR GA13-17187S Institutional support: RVO:67985807 Keywords : rules extraction from data * observational calculus * generalized quantifiers * copulas * hierarchical Archimedean copulas Subject RIV: IN - Informatics, Computer Science

  14. Observer Based Sliding Mode Attitude Control: Theoretical and Experimental Results

    Directory of Open Access Journals (Sweden)

    U. Jørgensen

    2011-07-01

    Full Text Available In this paper we present the design of a sliding mode controller for attitude control of spacecraft actuated by three orthogonal reaction wheels. The equilibrium of the closed loop system is proved to be asymptotically stable in the sense of Lyapunov. Due to cases where spacecraft do not have angular velocity measurements, an estimator for the generalized velocity is derived and asymptotic stability is proven for the observer. The approach is tested on an experimental platform with a sphere shaped Autonomous Underwater Vehicle SATellite: AUVSAT, developed at the Norwegian University of Science and Technology.

  15. Ground-based VLBI observations of orbiters and landers.

    Science.gov (United States)

    Cimo, G.; Duev, D.; Molera Calves, G.; Bocanegra Bohamon, T.; Pogrebenko, S.; Gurvits, L.

    2015-10-01

    Phase referencing near-field VLBI observations and radial Doppler measurements of spacecraft provide ultra-precise estimates of spacecraft state vectors. These measurements can be used for a variety of scientific applications, both fundamental and applied, including planetary science, improvement of ephemerides, ultra-precise celestial mechanics of planetary systems, gravimetry, spacecraft orbit determination, and fundamental physics. Precise determination of the lateral position of spacecraft on the celestial sphere is the main deliverable of the Planetary Radio Interferometry and Doppler Experiment (PRIDE). This technique is complementary to radio science experiments and addresses those areas of spacecraft mission science objectives that require accurate estimation of spacecraft state vector.

  16. NOISY OBSERVATION BASED STABILIZATION AND OPTIMIZATION FOR UNKNOWN SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    CHEN Hanfu(Han-Fu Chen)

    2003-01-01

    The paper addresses optimization of a performance function which either is optimized via stabilizing and controlling the underlying unknown system or is directly optimized on the basis of its noise-corrupted observations. For the first case the unknown system is identified and then the indirect adaptive control approach is applied to optimize the performance function. For the second case the stochastic approximation method is used to optimize the objective function, and it appears that a number of problems arising from applications may be reduced to the one solvable by this approach. The paper demonstrates some basic results in the area, but with no intention to give a complete survey.

  17. Linking Indigenous Knowledge and Observed Climate Change Studies

    Science.gov (United States)

    Alexander, Chief Clarence; Bynum, Nora; Johnson, Liz; King, Ursula; Mustonen, Tero; Neofotis, Peter; Oettle, Noel; Rosenzweig, Cynthia; Sakakibara, Chie; Shadrin, Chief Vyacheslav; Vicarelli, Marta; Waterhouse, Jon; Weeks, Brian

    2010-01-01

    We present indigenous knowledge narratives and explore their connections to documented temperature and other climate changes and observed climate change impact studies. We then propose a framework for enhancing integration of these indigenous narratives of observed climate change with global assessments. Our aim is to contribute to the thoughtful and respectful integration of indigenous knowledge with scientific data and analysis, so that this rich body of knowledge can inform science, and so that indigenous and traditional peoples can use the tools and methods of science for the benefit of their communities if they choose to do so. Enhancing ways of understanding such connections are critical as the Intergovernmental Panel on Climate Change Fifth Assessment process gets underway.

  18. Observations of radiographer communication: An exploratory study using Transactional Analysis

    International Nuclear Information System (INIS)

    Purpose: Communication in medical imaging is a neglected area of research, despite the necessity for good communication if optimum diagnostic images are to be achieved. Methods: The present study has investigated the styles of communication used in medical imaging, using an approach known as Transactional Analysis. This approach has been demonstrated previously as having reliability and validity, using observations and supporting interviews with medical imaging staff, along with inter-rater observations of radiographer-patient interactions. Results: The results indicate that Transactional Analysis can be used effectively for identifying and naming interaction events in diagnostic radiography, with diagnostic radiographers using five styles of communication. Conclusion: Radiographers tend to use Parental styles of communicating; these styles are commonly associated with a practitioner-centred approach to dealing with patients which often result in non-adherence

  19. Training on a vascular interventional simulator: an observational study

    International Nuclear Information System (INIS)

    Radiology registrars were observed performing a left renal artery angioplasty using a proprietary training simulator up to five times during their first year of training. Total procedure time, fluoroscopy times, and metric information from the machine were recorded. Each step of the procedure was judged by an observer and a mistake profile was generated. Fifty-two runs were completed by 12 trainees. The mean procedure time decreased from 16.6 min to 9.8 min over the five runs. The number of mistakes ranged from zero to ten and the mean number of mistakes made varied from 0.7 to 2.6 per procedure without any particular trend. Our study demonstrates that training on the simulator does improve performance. The mistakes made throughout training indicates the potential benefit from further simulator training. It remains unclear how to integrate this form of training in current educational programs. (orig.)

  20. Global ozone forecasting based on ERS-2 GOME observations

    Directory of Open Access Journals (Sweden)

    H. J. Eskes

    2002-07-01

    Full Text Available The availability of near-real time ozone observations from satellite instruments has recently initiated the development of ozone data assimilation systems. In this paper we present the results of an ozone assimilation and forecasting system, in use since Autumn 2000. The forecasts are produced by an ozone transport and chemistry model, driven by the operational medium range forecasts of ECMWF. The forecasts are initialised with realistic ozone distributions, obtained by the assimilation of near-real time total column observations of the GOME spectrometer on ERS-2. The forecast error diagnostics demonstrate that the system produces meaningful total ozone forecasts for up to 6 days in the extratropics. In the tropics meaningful forecasts of the small anomalies are restricted to shorter periods of about two days with the present model setup. It is demonstrated that important events, such as the breakup of the South Pole ozone hole and mini-hole events above Europe can be successfully predicted 4--5 days in advance.

  1. On Observer-Based Control of Nonlinear Systems

    OpenAIRE

    Robertsson, Anders

    1999-01-01

    Filtering and reconstruction of signals play a fundamental role in modern signal processing, telecommunications, and control theory and are used in numerous applications. The feedback principle is an important concept in control theory. Many different control strategies are based on the assumption that all internal states of the control object are available for feedback. In most cases, however, only a few of the states or some functions of the states can be measured. This circumstance ...

  2. Femtosecond direct observation of charge transfer between bases in DNA

    OpenAIRE

    Wan, Chaozhi; Fiebig, Torsten; Schiemann, Olav; Barton, Jacqueline K.; Zewail, Ahmed H.

    2000-01-01

    Charge transfer in supramolecular assemblies of DNA is unique because of the notion that the π-stacked bases within the duplex may mediate the transport, possibly leading to damage and/or repair. The phenomenon of transport through π-stacked arrays over a long distance has an analogy to conduction in molecular electronics, but the mechanism still needs to be determined. To decipher the elementary steps and the mechanism, one has to directly measure the dynamics in ...

  3. Sensorless DC motor drive via optimal observer-based servo control

    Energy Technology Data Exchange (ETDEWEB)

    Thananchai Keephakpreeda [Thammasat University (Thailand). School of Industrial and Mechanical Engineering

    2002-07-01

    This paper proposes an alternative design of a sensorless DC motor drive via optimal observer-based servo control. Without the speed sensor, the extended Luenberger observer is implemented to estimate the rotor speed of the DC motor in the presence of the disturbance torque. With this knowledge of the speed estimated from the observer, the servo state-feedback controller can drive such a rotor speed to follow the desired one. The stability and performance of the DC drive system can be guaranteed by the optimal control which minimizes the H{sub 2} norm of the closed-loop feedback control and observer system. The simulation and experimental studies are demonstrated for the effectiveness of the proposed control methodology in a practical approach for the sensorless DC drive. (author)

  4. Observer-based H-infinity output feedback control with feedback gain and observer gain variations for Delta operator system

    Institute of Scientific and Technical Information of China (English)

    Ruiquan LIN; Fuwen YANG; Renchong PENG

    2009-01-01

    Considering that the controller feedback gain and the observer gain are of additive norm-bounded variations, a design method of observer-based H-infinity output feedback controller for uncertain Delta operator systems is proposed in this paper. A sufficient condition of such controllers is presented in linear matrix inequality (LMI) forms. A numerical example is then given to illustrate the effectiveness of this method, that is, the obtained controller guarantees the closed-loop system asymptotically stable and the expected H-infinity performance even if the controller feedback gain and the observer gain are varied.

  5. Experience from the Argentine Pegvisomant Observational Study: preliminary data.

    Science.gov (United States)

    García Basavilbaso, N; Guitelman, M; Nagelberg, A; Stalldecker, G; Carabelli, A; Bruno, O; Danilowitz, K; Manavela, M; Mallea Gil, S; Ballarino, C; Guelman, R; Katz, D; Fidalgo, S; Leal, R; Fideleff, H; Servidio, M; Bruera, D; Librandi, F; Chervin, A; Vitale, M; Basso, A

    2010-01-01

    The GH receptor antagonist pegvisomant is an efficient agent to achieve biochemical control of acromegaly in those cases refractory to surgery and medical therapy with somatostatin analogs. We conducted an observational multicenter study consisting of data collection in accordance with the standard management of patients with acromegaly in everyday practice. We reviewed the medical records of 28 patients, 23 females, who were treated with pegvisomant due to the lack of biochemical response or intolerance to the somatostatin analogs. The objective was to monitor long-term safety and efficacy of the antagonist. 82% of the patients had previous pituitary surgery, 53.6% radiotherapy and 96.4% received medical therapy for acromegaly. Only 19.2% of the patients had pituitary residual tumor size larger than 1 cm, the remainder harbored a microadenoma or no visible tumor in the pituitary images. In terms of biochemical efficacy, IGF-I levels decreased to normal ranges in 45% and 58.8% of patients after 3 and 6 months of treatment, respectively, the daily mean dose of pegvisomant being 9.6+/-1.1 mg. Adverse events, potentially related to pegvisomant were reported in 6 patients (21.4%), local injection site reaction and elevated liver enzymes being the most frequent. Tumor size did not show enlargement in the evaluated population (15 patients) during the period of the study. This paper presents preliminary data from a small observational study in Argentina which represents the first database in our country. PMID:20616494

  6. Observer based parallel IM speed and parameter estimation

    Directory of Open Access Journals (Sweden)

    Skoko Saša

    2014-01-01

    Full Text Available The detailed presentation of modern algorithm for the rotor speed estimation of an induction motor (IM is shown. The algorithm includes parallel speed and resistance parameter estimation and allows a robust shaft-sensorless operation in diverse conditions, including full load and low speed operation with a large thermal drift. The direct connection between the injected electric signal in the d-axis and the component of injected rotor flux were pointed at. The algorithm that has been applied in the paper uses the extracted component of the injected rotor flux in the d-axis from the observer state vector and filtrated measured electricity of one motor phase. By applying the mentioned algorithm, the system converges towards the given reference. [Projekat Ministarstva nauke Republike Srbije, br. III 42004

  7. Extended State Observer based control for coaxial-rotor UAV.

    Science.gov (United States)

    Rida Mokhtari, M; Choukchou Braham, Amal; Cherki, Brahim

    2016-03-01

    This paper considers the problem of controlling the position and the orientation of a Coaxial-Rotor Unmanned Aerial Vehicle -CRUAV- despite unknown aerodynamic efforts. A hierarchical flight controller is designed, allowing the trajectory tracking and the stabilization of the vehicle. The designed controller is build through a hierarchical approach yielding two control loops, an inner one to control the attitude and an outer one to control the translational trajectory of the rotorcraft. An Extended State Observer -ESO- is used to estimate the state and the unknown aerodynamic disturbances. The analysis further extends to the design of a control law that takes the disturbance estimation procedure into account. Numerical simulations are carried out to demonstrate the efficiency of the proposed control strategy. PMID:26708305

  8. PolarBase: a data base of high resolution spectropolarimetric stellar observations

    CERN Document Server

    Petit, P; Théado, S; Paletou, F; Manset, N; Morin, J; Marsden, S C; Jeffers, S V

    2014-01-01

    PolarBase is an evolving data base that contains all stellar data collected with the ESPaDOnS and NARVAL high-resolution spectropolarimeters, in their reduced form, as soon as they become public. As of early 2014, observations of 2,000 stellar objects throughout the Hertzsprung-Russell diagram are available. Intensity spectra are available for all targets, and the majority of the observations also include simultaneous spectra in circular or linear polarization, with the majority of the polarimetric measurements being performed only in circularly polarized light (Stokes V). Observations are associated with a cross-correlation pseudo-line profile in all available Stokes parameters, greatly increasing the detectability of weak polarized signatures. Stokes V signatures are detected for more than 300 stars of all masses and evolutionary stages, and linear polarization is detected in 35 targets. The detection rate in Stokes V is found to be anti-correlated with the stellar effective temperature. This unique set of ...

  9. Serum YKL-40 and gestational diabetes - an observational cohort study

    DEFF Research Database (Denmark)

    Gybel-Brask, Dorte; Johansen, Julia S; Christiansen, Ib J;

    2016-01-01

    To examine serum YKL-40 in women developing gestational diabetes mellitus (GDM). In the present large observational cohort study of 1179 pregnant women, we determined serum YKL-40 four times during pregnancy (at gestational age 12, 20, 25, and 32 weeks). Pregnancy outcome was obtained from medical...... records. Sixty-eight women (5.8%) developed GDM. Serum YKL-40 increased from gestational age (GA) 12 weeks and the following weeks in the women who developed GDM and was independent of BMI, parity, and maternal age (OR = 2.69, 95% CI: 1.45-5.00, p = 0.002). No association was found between serum YKL-40...

  10. Study of a microflare observed with SUMER and TRACE

    Science.gov (United States)

    Gontikakis, C.; Winebarger, A. R.

    2012-01-01

    We study a GOES-A1 microflare, observed in active region NOAA 8541 on May 15, 1999 with TRACE images, SUMER spectra and MDI magnetograms. In TRACE filtergrams of 171A and 195A, the microflare is composed of two interacting, 20Mm long, loops. SUMER observations include four spectral lines: the Si II 1533A (a chromospheric line), the C IV 1548A, 1550 A (transition region lines) and the Ne VIII 770 A (a coronal line). These spectra record the impulsive stage of the microflare, which appears as a bright feature at the west footpoint of the TRACE loops. In an area adjacent to the microflare we observe, for the first time on the solar disk, a region where the lines intensity ratio 1548A/1550A equals to 4 which means that resonant scattering dominates the emission process. Over the microflare, the SUMER spectral lines are blue shifted, indicating upflows due to explosive evaporation, as well as red shifted, indicating, cooling downward motions. Moreover, the C IV microflare spectral profiles, indicate upflows of ~200 km/s even if most of them are damaged due to the SUMER detector over exposure, while the Si II 1533A profiles are self-reversed due to opacity effects.

  11. Space-based optical observation system suitable for micro satellite

    OpenAIRE

    Piattoni, Jacopo

    2015-01-01

    The PhD research activity has taken place in the space debris field. In detail, it is focused on the possibility of detecting space debris from the space based platform. The research is focused at the same time on the software and the hardware of this detection system. For the software, a program has been developed for being able to detect an object in space and locate it in the sky solving the star field. For the hardware, the possibility of adapting a ground telescope for space activity has...

  12. Comparison of hydrological simulations of climate change using perturbation of observations and distribution-based scaling

    DEFF Research Database (Denmark)

    Van Roosmalen, Lieke Petronella G; Sonnenborg, Torben; Jensen, Karsten Høgh; Christensen, Jens Hesselbjerg

    2011-01-01

    HIRHAM4 regional climate model (RCM). The aim of this study was to determine whether the choice of bias-correction method, applied to the RCM data, aff ected the projected hydrological changes. One method consisted of perturbation of observed data (POD) using climate change signals derived from the RCM...... output, while the other consisted of distribution-based scaling (DBS) of the RCM output. Distributionbased scaling resulted in RCM control period data closely approaching the observed climate data and thereby considerably improved the simulation of recharge and stream discharges. When comparing the...

  13. Entamoeba histolytica: observations on metabolism based on thegenome sequence

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Iain J.; Loftus, Brendan J.

    2005-07-01

    The sequencing of the genome of Entamoeba histolytica has allowed a reconstruction of its metabolic pathways, many of which are unusual for a eukaryote. Based on the genome sequence, it appears that amino acids may play a larger role than previously thought in energy metabolism, with roles in both ATP synthesis and NAD regeneration. Arginine decarboxylase may be involved in survival of E. histolytica during its passage through the stomach. The usual pyrimidine synthesis pathway is absent, but a partial pyrimidine degradation pathway could be part of a novel pyrimidine synthesis pathway. Ribonucleotide reductase was not found in the E. histolytica genome, but it was found in the close relatives Entamoeba invadens and Entamoeba moshkovskii, suggesting a recent loss from E. histolytica. The usual eukaryotic glucose transporters are not present, but members of a prokaryotic monosaccharide transporter family are present.

  14. Ensemble-Based Assimilation of Aerosol Observations in GEOS-5

    Science.gov (United States)

    Buchard, V.; Da Silva, A.

    2016-01-01

    MERRA-2 is the latest Aerosol Reanalysis produced at NASA's Global Modeling Assimilation Office (GMAO) from 1979 to present. This reanalysis is based on a version of the GEOS-5 model radiatively coupled to GOCART aerosols and includes assimilation of bias corrected Aerosol Optical Depth (AOD) from AVHRR over ocean, MODIS sensors on both Terra and Aqua satellites, MISR over bright surfaces and AERONET data. In order to assimilate lidar profiles of aerosols, we are updating the aerosol component of our assimilation system to an Ensemble Kalman Filter (EnKF) type of scheme using ensembles generated routinely by the meteorological assimilation. Following the work performed with the first NASA's aerosol reanalysis (MERRAero), we first validate the vertical structure of MERRA-2 aerosol assimilated fields using CALIOP data over regions of particular interest during 2008.

  15. Atmospheric contamination for CMB ground-based observations

    CERN Document Server

    Errard, J; Akiba, Y; Arnold, K; Atlas, M; Baccigalupi, C; Barron, D; Boettger, D; Borrill, J; Chapman, S; Chinone, Y; Cukierman, A; Delabrouille, J; Dobbs, M; Ducout, A; Elleflot, T; Fabbian, G; Feng, C; Feeney, S; Gilbert, A; Goeckner-Wald, N; Halverson, N W; Hasegawa, M; Hattori, K; Hazumi, M; Hill, C; Holzapfel, W L; Hori, Y; Inoue, Y; Jaehnig, G C; Jaffe, A H; Jeong, O; Katayama, N; Kaufman, J; Keating, B; Kermish, Z; Keskitalo, R; Kisner, T; Jeune, M Le; Lee, A T; Leitch, E M; Leon, D; Linder, E; Matsuda, F; Matsumura, T; Miller, N J; Myers, M J; Navaroli, M; Nishino, H; Okamura, T; Paar, H; Peloton, J; Poletti, D; Puglisi, G; Rebeiz, G; Reichardt, C L; Richards, P L; Ross, C; Rotermund, K M; Schenck, D E; Sherwin, B D; Siritanasak, P; Smecher, G; Stebor, N; Steinbach, B; Stompor, R; Suzuki, A; Tajima, O; Takakura, S; Tikhomirov, A; Tomaru, T; Whitehorn, N; Wilson, B; Yadav, A; Zahn, O

    2015-01-01

    Atmosphere is one of the most important noise sources for ground-based Cosmic Microwave Background (CMB) experiments. By increasing optical loading on the detectors, it amplifies their effective noise, while its fluctuations introduce spatial and temporal correlations between detected signals. We present a physically motivated 3d-model of the atmosphere total intensity emission in the millimeter and sub-millimeter wavelengths. We derive an analytical estimate for the correlation between detectors time-ordered data as a function of the instrument and survey design, as well as several atmospheric parameters such as wind, relative humidity, temperature and turbulence characteristics. Using numerical computation, we examine the effect of each physical parameter on the correlations in the time series of a given experiment. We then use a parametric-likelihood approach to validate the modeling and estimate atmosphere parameters from the POLARBEAR-I project first season data set. We compare our results to previous st...

  16. Complete control, direct observation and study of molecular super rotors

    CERN Document Server

    Korobenko, Aleksey; Milner, Valery

    2013-01-01

    Extremely fast rotating molecules carrying significantly more energy in their rotation than in any other degree of freedom are known as "super rotors". It has been speculated that super rotors may exhibit a number of unique and intriguing properties. Theoretical studies showed that ultrafast molecular rotation may change the character of molecular scattering from solid surfaces, alter molecular trajectories in external fields, make super rotors surprisingly stable against collisions, and lead to the formation of gas vortices. New ways of molecular cooling and selective chemical bond breaking by ultrafast spinning have been proposed. Owing to the fundamental laws of nature, bringing a large number of molecules to fast, directional and synchronous rotation is rather challenging. As a result, only indirect evidence of super rotors has been reported to date. Here we demonstrate the first controlled creation, direct observation and study of molecular super rotors. Using intense laser pulses tailored to produce an ...

  17. Pandemrix™ and narcolepsy: A critical appraisal of the observational studies.

    Science.gov (United States)

    Verstraeten, Thomas; Cohet, Catherine; Dos Santos, Gaël; Ferreira, Germano Lc; Bollaerts, Kaatje; Bauchau, Vincent; Shinde, Vivek

    2016-01-01

    A link between Pandemrix™ (AS03-adjuvanted H1N1 pandemic influenza vaccine, GSK Vaccines, Belgium) and narcolepsy was first suspected in 2010 in Sweden and Finland following a number of reports in children and adolescents. Initial scepticism about the reported association faded as additional countries reported similar findings, leading several regulatory authorities to restrict the use of Pandemrix™. The authors acknowledge that currently available data suggest an increased risk of narcolepsy following vaccination with Pandemrix™; however, from an epidemiologist's perspective, significant methodological limitations of the studies have not been fully addressed and raise questions about the reported risk estimates. We review the most important biases and confounders that potentially occurred in 12 European studies of the observed association between Pandemrix™ and narcolepsy, and call for further analyses and debate. PMID:26379011

  18. 222Rn Observations for Climate and Air Quality Studies

    International Nuclear Information System (INIS)

    This paper identifies the current major applications for 222Rn in atmospheric research. Two of these applications, air mass transport and vertical mixing in the lower atmosphere, are illustrated by four separate case studies: (1) Using 222Rn to identify the geographical extent, strength and seasonal variability of land and oceanic emissions; (2) Using 222Rn in pollution studies to improve the performance of clustering algorithms used to define source regions; (3) Using near-surface hourly 222Rn gradient observations from towers as tall as 200 m to investigate diurnal dilution effects in the boundary layer with changing atmospheric stability; and (4) Using vertical 222Rn profile 'snapshots' measured from light aircraft up to 4 km above ground level to contrast boundary layer entrainment rates between clear-sky, convective and stratiform cloud cases. Lastly, a recent set of 222Rn and 222Rn progeny observations is used to discuss the 222Rn/progeny equilibrium factor and illustrate some common problems associated with using 222Rn progeny as a proxy for 222Rn. (author)

  19. Wave energy resource assessment based on satellite observations around Indonesia

    Science.gov (United States)

    Ribal, Agustinus; Zieger, Stefan

    2016-06-01

    A preliminary assessment of wave energy resource around Indonesian's ocean has been carried out by means of analyzing satellite observations. The wave energy flux or wave power can be approximated using parameterized sea states. Wave power scales with significant wave height, characteristic wave period and water depth. In this approach, the significant wave heights were obtained from ENVISAT (Environmental Satellite) data which have been calibrated. However, as the characteristic wave period is rarely specified and therefore must be estimated from other variables when information about the wave spectra is unknown. Here, the characteristic wave period was calculated with an empirical model that utilizes altimeter estimates of wave height and backscatter coefficient originally proposed. For the Indonesian region, wave power energy is calculated over two periods of one year each and was compared with the results from global hindcast carried out with a recent release of wave model WAVEWATCH III. We found that, the most promising wave power energy regions around the Indonesian archipelago are located in the south of Java island and the south west of Sumatera island. In these locations, about 20 - 30 kW/m (90th percentile: 30-50 kW/m, 99th percentile: 40-60 kW/m) wave power energy on average has been found around south of Java island during 2010. Similar results have been found during 2011 at the same locations. Some small areas which are located around north of Irian Jaya (West Papua) are also very promising and need further investigation to determine its capacity as a wave energy resource.

  20. An Observer-Based Adaptive Iterative Learning Control Using Filtered-FNN Design for Robotic Systems

    OpenAIRE

    Ying-Chung Wang; Chiang-Ju Chien

    2014-01-01

    An observer-based adaptive iterative learning control using a filtered fuzzy neural network is proposed for repetitive tracking control of robotic systems. A state tracking error observer is introduced to design the iterative learning controller using only the measurement of joint position. We first derive an observation error model based on the state tracking error observer. Then, by introducing some auxiliary signals, the iterative learning controller is proposed based on the use of an aver...

  1. GA-based tuning of nonlinear observers for sensorless control of IPMSMs

    OpenAIRE

    Bhangu, B S; Bingham, Chris

    2004-01-01

    The paper considers two observer-based rotor position estimation schemes for sensorless control of interior permanent magnet synchronous machines (IPMSMs). Emphasis is given to techniques based on feedback linearisation followed by Luenberger observer design, and direct design of nonlinear observers. Genetic algorithms (GAs) based on the principles of evolution, natural selection and genetic mutation are employed to address difficulties in selecting correction gains for the observers, since n...

  2. Foot Length, Chest Circumference, and Mid Upper Arm Circumference Are Good Predictors of Low Birth Weight and Prematurity in Ethnic Minority Newborns in Vietnam: A Hospital-Based Observational Study

    Science.gov (United States)

    Thi, Hai Nguyen; Khanh, Dung Khu Thi; Thu, Ha Le Thi; Thomas, Emma G.; Lee, Katherine J.; Russell, Fiona M.

    2015-01-01

    Background The evaluation of tools to accurately identify low birth weight (LBW) and/or premature newborns in resource-limited countries is a research priority. We explored the use of foot length, chest circumference, and mid-upper arm circumference (MUAC) measured within 24 h as diagnostic tools for identifying newborns who are LBW, premature, or both; and compared measurements taken at birth with those taken at five days of age. Materials and Methods An observational study was undertaken in Hoa Binh Province General Hospital, Vietnam, in ethnic minority newborns. Birth weight, foot length, chest circumference, and MUAC were measured within 24 h of birth and in a subset of 200, were repeated on day five of life. Gestational age was estimated using the New Ballard Score. Receiver Operating Characteristic curves and optimal cut-points (the point with the highest sensitivity and specificity where the sensitivity was at least 0.8) were calculated, for predicting prematurity, LBW, and both. Measurements within 24 h and at five days of life were compared. Results 485 newborns were recruited. Chest circumference and MUAC measured within 24 h of birth were found to be highly predictive of LBW (both yielding area under the curve [AUC] of 0.98, 95% confidence interval [CI] 0.96–0.99), and performed marginally better than foot length (AUC 0.94, 95%CI 0.92–0.96). The optimal cut-points for measurements within 24 h of birth were ≤7.4cm for foot length; ≤30.4cm for chest circumference; and ≤ 9.0cm for MUAC. There was statistical evidence that anthropometric measurements taken within 24 h of birth were higher than measurements on day five (p<0.02 for all anthropometric measurements) but the magnitude of these differences was small (at most 2mm). Conclusions All measurements taken within 24 h of birth were good predictors of LBW, prematurity and both. Differences in measurements taken within 24 h and on day five were not clinically relevant. Further research will ensure

  3. Estimating moisture transport over oceans using space-based observations

    Science.gov (United States)

    Liu, W. Timothy; Wenqing, Tang

    2005-01-01

    The moisture transport integrated over the depth of the atmosphere (0) is estimated over oceans using satellite data. The transport is the product of the precipitable water and an equivalent velocity (ue), which, by definition, is the depth-averaged wind velocity weighted by humidity. An artificial neural network is employed to construct a relation between the surface wind velocity measured by the spaceborne scatterometer and coincident ue derived using humidity and wind profiles measured by rawinsondes and produced by reanalysis of operational numerical weather prediction (NWP). On the basis of this relation, 0 fields are produced over global tropical and subtropical oceans (40_N- 40_S) at 0.25_ latitude-longitude and twice daily resolutions from August 1999 to December 2003 using surface wind vector from QuikSCAT and precipitable water from the Tropical Rain Measuring Mission. The derived ue were found to capture the major temporal variability when compared with radiosonde measurements. The average error over global oceans, when compared with NWP data, was comparable with the instrument accuracy specification of space-based scatterometers. The global distribution exhibits the known characteristics of, and reveals more detailed variability than in, previous data.

  4. Observation of Neutron Skyshine from an Accelerator Based Neutron Source

    Science.gov (United States)

    Franklyn, C. B.

    2011-12-01

    A key feature of neutron based interrogation systems is the need for adequate provision of shielding around the facility. Accelerator facilities adapted for fast neutron generation are not necessarily suitably equipped to ensure complete containment of the vast quantity of neutrons generated, typically >1011 nṡs-1. Simulating the neutron leakage from a facility is not a simple exercise since the energy and directional distribution can only be approximated. Although adequate horizontal, planar shielding provision is made for a neutron generator facility, it is sometimes the case that vertical shielding is minimized, due to structural and economic constraints. It is further justified by assuming the atmosphere above a facility functions as an adequate radiation shield. It has become apparent that multiple neutron scattering within the atmosphere can result in a measurable dose of neutrons reaching ground level some distance from a facility, an effect commonly known as skyshine. This paper describes a neutron detection system developed to monitor neutrons detected several hundred metres from a neutron source due to the effect of skyshine.

  5. Mucocutaneous manifestations of acquired hypoparathyroidism: An observational study

    Directory of Open Access Journals (Sweden)

    Somenath Sarkar

    2012-01-01

    Full Text Available Hypoparathyroidism is a disorder of calcium and phosphorus metabolism due to decreased secretion of parathyroid hormone. Hypoparathyroidism can be hereditary and acquired. Acquired hypoparathyroidism usually occurs following neck surgery (thyroid surgery or parathyroid surgery. Along with systemic manifestations, hypoparathyroidism produces some skin manifestations. Lack of study regarding mucocutaneous manifestations of acquired hypoparathyroidism prompted us to undertake this study. To evaluate the mucocutaneous manifestations of acquired hypoparathyroidism. An observational study done in a tertiary care hospital of Kolkata by comprehensive history taking, through clinical examination and relevant laboratory investigations. Twenty-one patients were included in the study. The commonest form of acquired hypoparathyroidism was neck surgery (thyroidectomy and parathyroidectomy operation. Mucocutaneous manifestations were present in 76.19% of patients. The most frequent mucocutaneous manifestation was found in the hairs like the loss of axillary hair (61.9%, loss of pubic hair (52.38%, coarsening of body hair (47.62%, and alopecia areata (9.52%. The nail changes noted were brittle and ridged nail, followed by onycholysis, onychosezia, and onychomedesis. The most common skin features were xerotic skin in 11 patients (52.38%, followed by pellagra-like skin pigmentation, pustular psoriasis and acne form eruption, bullous impetigo, etc. Mucosa was normal in all the cases excepting the one which showed oral candidiasis.

  6. Measuring the Quality of Observational Study Data in an International HIV Research Network

    OpenAIRE

    Duda, Stephany N; Shepherd, Bryan E.; Gadd, Cynthia S; Masys, Daniel R.; McGowan, Catherine C.

    2012-01-01

    Observational studies of health conditions and outcomes often combine clinical care data from many sites without explicitly assessing the accuracy and completeness of these data. In order to improve the quality of data in an international multi-site observational cohort of HIV-infected patients, the authors conducted on-site, Good Clinical Practice-based audits of the clinical care datasets submitted by participating HIV clinics. Discrepancies between data submitted for research and data in t...

  7. Providers' response to child eating behaviors: A direct observation study.

    Science.gov (United States)

    Tovar, Alison; Vaughn, Amber E; Fallon, Megan; Hennessy, Erin; Burney, Regan; Østbye, Truls; Ward, Dianne S

    2016-10-01

    Child care providers play an important role in feeding young children, yet little is known about children's influence on providers' feeding practices. This qualitative study examines provider and child (18 months -4 years) feeding interactions. Trained data collectors observed 200 eating occasions in 48 family child care homes and recorded providers' responses to children's meal and snack time behaviors. Child behaviors initiating provider feeding practices were identified and practices were coded according to higher order constructs identified in a recent feeding practices content map. Analysis examined the most common feeding practices providers used to respond to each child behavior. Providers were predominately female (100%), African-American (75%), and obese (77%) and a third of children were overweight/obese (33%). Commonly observed child behaviors were: verbal and non-verbal refusals, verbal and non-verbal acceptance, being "all done", attempts for praise/attention, and asking for seconds. Children's acceptance of food elicited more autonomy supportive practices vs. coercive controlling. Requests for seconds was the most common behavior, resulting in coercive controlling practices (e.g., insisting child eat certain food or clean plate). Future interventions should train providers on responding to children's behaviors and helping children become more aware of internal satiety and hunger cues. PMID:27328098

  8. [Observational study of atmospheric HONO in summer of Beijing].

    Science.gov (United States)

    Zhu, Yan-Wu; Liu, Wen-Qing; Xie, Pin-Hua; Dou, Ke; Liu, Shi-Sheng; Si, Fu-Qi; Li, Su-Wen; Qin, Min

    2009-06-15

    The concentration of HONO, NO2, O3 and other atmospheric pollutants were observed continuously by using differential optical absorption spectroscopy (DOAS) from 2007-08-14 to 2007-08-24 in Beijing, China. Diurnal variation characteristics of HONO and NO2 were analyzed. The HONO levels originated from the nocturnal direct emission were discussed. And the correlation between the heterogeneous formation of HONO and its related factors (BC, RH, and so on) was studied. The results showed that HONO had two peaks at about 01:00 and 06:00, respectively, while two peaks of NO2 concentrations appeared at about 01:00 and 07:00. The highest HONO(em)/HONO ratio of 31.3% was observed at about 20:00 between 19:00 to 07:00, and the average ratio was 15%. Good correlation of HONO(corr)/NO2 ratio with BC and RH at night was obtained. The correlation suggested that heterogeneous NO2 to HONO conversion processes may occur on BC surfaces by reaction with absorption water, and the average nighttime conversion frequency from NO2 into HONO (HONO/NO2) was calculated about 0.8% x h(-1). At the same time, the results showed that heterogeneous formation of HONO was increased with RH and inhibited at RH > 80%, and the hypothesis was further supported by detailed analysis of selected case. PMID:19662832

  9. Comparison of Precipitation Observations from a Prototype Space-based Cloud Radar and Ground-based Radars

    Institute of Scientific and Technical Information of China (English)

    LIU Liping; ZHANG Zhiqiang; YU Danru; YANG Hu; ZHAO Chonghui; ZHONG Lingzhi

    2012-01-01

    A prototype space-based cloud radar has been developed and was installed on an airplane to observe a precipitation system over Tianjin,China in July 2010.Ground-based S-band and Ka-band radars were used to examine the observational capability of the prototype. A cross-comparison algorithm between different wavelengths,spatial resolutions and platform radars is presented.The reflectivity biases,correlation coefficients and standard deviations between the radars are analyzed.The equivalent reflectivity bias between the S- and Ka-band radars were simulated with a given raindrop size distribution.The results indicated that reflectivity bias between the S- and Ka-band radars due to scattering properties was less than 5 dB,and for weak precipitation the bias was negligible. The prototype space-based cloud radar was able to measure a reasonable vertical profile of reflectivity,but the reflectivity below an altitude of 1.5 km above ground level was obscured by ground clutter.The measured reflectivity by the prototype space-based cloud radar was approximately 10.9 dB stronger than that by the S-band Doppler radar (SA radar),and 13.7 dB stronger than that by the ground-based cloud radar.The reflectivity measured by the SA radar was 0.4 dB stronger than that by the ground-based cloud radar.This study could provide a method for the quantitative examination of the observation ability for space-based radars.

  10. Detection of Cardiovascular Anomalies: An Observer-Based Approach

    KAUST Repository

    Ledezma, Fernando

    2012-07-01

    In this thesis, a methodology for the detection of anomalies in the cardiovascular system is presented. The cardiovascular system is one of the most fascinating and complex physiological systems. Nowadays, cardiovascular diseases constitute one of the most important causes of mortality in the world. For instance, an estimate of 17.3 million people died in 2008 from cardiovascular diseases. Therefore, many studies have been devoted to modeling the cardiovascular system in order to better understand its behavior and find new reliable diagnosis techniques. The lumped parameter model of the cardiovascular system proposed in [1] is restructured using a hybrid systems approach in order to include a discrete input vector that represents the influence of the mitral and aortic valves in the different phases of the cardiac cycle. Parting from this model, a Taylor expansion around the nominal values of a vector of parameters is conducted. This expansion serves as the foundation for a component fault detection process to detect changes in the physiological parameters of the cardiovascular system which could be associated with cardiovascular anomalies such as atherosclerosis, aneurysm, high blood pressure, etc. An Extended Kalman Filter is used in order to achieve a joint estimation of the state vector and the changes in the considered parameters. Finally, a bank of filters is, as in [2], used in order to detect the appearance of heart valve diseases, particularly stenosis and regurgitation. The first numerical results obtained are presented.

  11. Observer-Based Fault Estimation and Accomodation for Dynamic Systems

    CERN Document Server

    Zhang, Ke; Shi, Peng

    2013-01-01

    Due to the increasing security and reliability demand of actual industrial process control systems, the study on fault diagnosis and fault tolerant control of dynamic systems has received considerable attention. Fault accommodation (FA) is one of effective methods that can be used to enhance system stability and reliability, so it has been widely and in-depth investigated and become a hot topic in recent years. Fault detection is used to monitor whether a fault occurs, which is the first step in FA. On the basis of fault detection, fault estimation (FE) is utilized to determine online the magnitude of the fault, which is a very important step because the additional controller is designed using the fault estimate. Compared with fault detection, the design difficulties of FE would increase a lot, so research on FE and accommodation is very challenging. Although there have been advancements reported on FE and accommodation for dynamic systems, the common methods at the present stage have design difficulties, whi...

  12. The compression mechanism of garnets based on in situ observations

    Science.gov (United States)

    Dymshits, Anna; Sharygin, Igor; Litasov, Konstantin; Shatskiy, Anton

    2014-05-01

    freedom is minimized and such relations between the XO8 and YO6 sites provide evidence for comparatively more rigid structure. In case of uvarovite the bulk modulus is 162 GPa (Leger et al., 1990), while for Knr we obtain 154 GPa. Such relations between the XO8 and YO6 sites provide evidence for comparatively more rigid structure. As a result, Na-maj with all octahedral sites occupied by silicon has the largest value of the bulk modulus among garnets. It would be interesting to study compressibility of Li-majorite expressed by Yang et al. (2009). That phase has smaller cell volume (1430 Å3) and X-O distance (2.26 Å) but the same YO6 polyhedra fully occupied by silicon. The study was supported by Ministry of Education and Science of Russian Federation, project Nos 14.B25.31.0032, MK-265.2014.5, Russian Foundation for Basic Research No 14-05-00957-a. Hazen, R.M., Downs, R.T., Conrad, P.G., Finger, L.W., Gasparik, T. Comparative compressibilities of majorite-type garnets // Physics and Chemistry of Minerals, 1994, v.21, p.344-349. Leger, J., Redon, A., Chateau, C. Compressions of synthetic pyrope, spessartine and uvarovite garnets up to 25 GPa // Physics and Chemistry of Minerals, 1990, v.17, p.161-167. Milman, V., Akhmatskaya, E., Nobes, R., Winkler, B., Pickard, C., White, J. Systematic ab initio study of the compressibility of silicate garnets // Acta Crystallographica Section B: Structural Science, 2001, v.57, p.163-177. Yang, H., Konzett, J., Frost, D.J., Downs, R.T. X-ray diffraction and Raman spectroscopic study of clinopyroxenes with six-coordinated Si in the Na(Mg0.5Si0.5)Si2O6-NaAlSi2O6 system // American Mineralogist, 2009, v.94, p.942-949.

  13. Runge-Kutta model-based nonlinear observer for synchronization and control of chaotic systems.

    Science.gov (United States)

    Beyhan, Selami

    2013-07-01

    This paper proposes a novel nonlinear gradient-based observer for synchronization and observer-based control of chaotic systems. The model is based on a Runge-Kutta model of the chaotic system where the evolution of the states or parameters is derived based on the error-square minimization. The stability and convergence conditions of observer and control methods are analyzed using a Lyapunov stability approach. In numerical simulations, the proposed observer and well-known sliding-mode observer are compared for the synchronization of a Lü chaotic system and observer-based stabilization of a Chen chaotic system. The noisy case for synchronization and parameter uncertainty case for stabilization are also considered for both observer-based methods. PMID:23672740

  14. A nanoflare based cellular automaton model and the observed properties of the coronal plasma

    CERN Document Server

    Fuentes, Marcelo López

    2016-01-01

    We use the cellular automaton model described in L\\'opez Fuentes \\& Klimchuk (2015, ApJ, 799, 128) to study the evolution of coronal loop plasmas. The model, based on the idea of a critical misalignment angle in tangled magnetic fields, produces nanoflares of varying frequency with respect to the plasma cooling time. We compare the results of the model with active region (AR) observations obtained with the Hinode/XRT and SDO/AIA instruments. The comparison is based on the statistical properties of synthetic and observed loop lightcurves. Our results show that the model reproduces the main observational characteristics of the evolution of the plasma in AR coronal loops. The typical intensity fluctuations have an amplitude of 10 to 15\\% both for the model and the observations. The sign of the skewness of the intensity distributions indicates the presence of cooling plasma in the loops. We also study the emission measure (EM) distribution predicted by the model and obtain slopes in log(EM) versus log(T) betw...

  15. Comparative Studies of Different Imputation Methods for Recovering Streamflow Observation

    Directory of Open Access Journals (Sweden)

    Minjeong Kim

    2015-12-01

    Full Text Available Faulty field sensors cause unreliability in the observed data that needed to calibrate and assess hydrology models. However, it is illogical to ignore abnormal or missing values if there are limited data available. This study addressed this problem by applying data imputation to replace incorrect values and recover missing streamflow information in the dataset of the Samho gauging station at Taehwa River (TR, Korea from 2004 to 2006. Soil and Water Assessment Tool (SWAT and two machine learning techniques, Artificial Neural Network (ANN and Self Organizing Map (SOM, were employed to estimate streamflow using reasonable flow datasets of Samho station from 2004 to 2009. The machine learning models were generally better at capturing high flows, while SWAT was better at simulating low flows.

  16. A parameterization of observer-based controllers: Bumpless transfer by covariance interpolation

    DEFF Research Database (Denmark)

    Stoustrup, Jakob; Komareji, Mohammad

    This paper presents an algorithm to interpolate between two observer-based controllers for a linear multivariable system such that the closed loop system remains stable throughout the interpolation. The method interpolates between the inverse Lyapunov functions for the two original state feedbacks...... and between the Lyapunov functions for the two original observer gains to determine an intermediate observer based controller....

  17. OBSERVATIONAL STUDY ON FOOT PRESSURE DISTRIBUTION IN YOUNG AND ADULTS

    Directory of Open Access Journals (Sweden)

    Kanimozhi,

    2014-08-01

    Full Text Available In the recent years, the plantar pressure has widely been accepted as a vital biomechanical parameter to evaluate human biomechanics.. The present study endeavours to find the effect of age in foot pressure distribution and its influence over medial, lateral, anterior and posterior mask of foot pressure distribution. It is an observational and comparative study on foot pressure distribution in young (25-35 years and adults (40-60 years. Materials such as anthropometric rod, weighing machine and Podia Scan including Harrison mats have been used for the purpose of this study. Both an inter group and intra group comparison has been made. The mean and SD values of medial & lateral masks in the case of young subjects were 16.98±2.80 & 16.13±2.77, while these were 13.72±1.59 & 19.38±1.58 in old subjects indicating the lateralisation of weight bearing in adults. Nevertheless, the difference in plantar pressure distribution was not statistically significant when anterior mask (t=1.819, p<0.05 and posterior mask (t=1.907,p<0.05 were compared between young and adults.

  18. Ground-based Observations of the Solar Sources of Space Weather (Invited Review)

    CERN Document Server

    Veronig, Astrid M

    2016-01-01

    Monitoring of the Sun and its activity is a task of growing importance in the frame of space weather research and awareness. Major space weather disturbances at Earth have their origin in energetic outbursts from the Sun: solar flares, coronal mass ejections and associated solar energetic particles. In this review we discuss the importance and complementarity of ground-based and space-based observations for space weather studies. The main focus is drawn on ground-based observations in the visible range of the spectrum, in particular in the diagnostically manifold H$\\alpha$ spectral line, which enables us to detect and study solar flares, filaments, filament eruptions, and Moreton waves. Existing H$\\alpha$ networks such as the GONG and the Global High-Resolution H$\\alpha$ Network are discussed. As an example of solar observations from space weather research to operations, we present the system of real-time detection of H$\\alpha$ flares and filaments established at Kanzelh\\"ohe Observatory (KSO; Austria) in the...

  19. Aneurysm Study of Pipeline in an Observational Registry (ASPIRe)

    Science.gov (United States)

    Kallmes, David F.; Brinjikji, Waleed; Boccardi, Edoardo; Ciceri, Elisa; Diaz, Orlando; Tawk, Rabih; Woo, Henry; Jabbour, Pascal; Albuquerque, Felipe; Chapot, Rene; Bonafe, Alain; Dashti, Shervin R.; Almandoz, Josser E. Delgado; Given, Curtis; Kelly, Michael E.; Cross, DeWitte T.; Duckwiler, Gary; Razack, Nasser; Powers, Ciaran J.; Fischer, Sebastian; Lopes, Demetrius; Harrigan, Mark R.; Huddle, Daniel; Turner, Raymond; Zaidat, Osama O.; Defreyne, Luc; Pereira, Vitor Mendes; Cekirge, Saruhan; Fiorella, David; Hanel, Ricardo A.; Lylyk, Pedro; McDougall, Cameron; Siddiqui, Adnan; Szikora, Istvan; Levy, Elad

    2016-01-01

    Background and Objective Few prospective studies exist evaluating the safety and efficacy of the Pipeline Embolization Device (PED) in the treatment of intracranial aneurysms. The Aneurysm Study of Pipeline In an observational Registry (ASPIRe) study prospectively analyzed rates of complete aneurysm occlusion and neurologic adverse events following PED treatment of intracranial aneurysms. Materials and Methods We performed a multicenter study prospectively evaluating patients with unruptured intracranial aneurysms treated with PED. Primary outcomes included (1) spontaneous rupture of the Pipeline-treated aneurysm; (2) spontaneous nonaneurysmal intracranial hemorrhage (ICH); (3) acute ischemic stroke; (4) parent artery stenosis, and (5) permanent cranial neuropathy. Secondary endpoints were (1) treatment success and (2) morbidity and mortality at the 6-month follow-up. Vascular imaging was evaluated at an independent core laboratory. Results One hundred and ninety-one patients with 207 treated aneurysms were included in this registry. The mean aneurysm size was 14.5 ± 6.9 mm, and the median imaging follow-up was 7.8 months. Twenty-four aneurysms (11.6%) were small, 162 (78.3%) were large and 21 (10.1%) were giant. The median clinical follow-up time was 6.2 months. The neurological morbidity rate was 6.8% (13/191), and the neurological mortality rate was 1.6% (3/191). The combined neurological morbidity/mortality rate was 6.8% (13/191). The most common adverse events were ischemic stroke (4.7%, 9/191) and spontaneous ICH (3.7%, 7/191). The complete occlusion rate at the last follow-up was 74.8% (77/103). Conclusions Our prospective postmarket study confirms that PED treatment of aneurysms in a heterogeneous patient population is safe with low rates of neurological morbidity and mortality. Patients with angiographic follow-up had complete occlusion rates of 75% at 8 months.

  20. Causal Inference in Repeated Observational Studies: A Case Study of eBay Product Releases

    OpenAIRE

    von Brzeski, Vadim; Taddy, Matt; Draper, David

    2015-01-01

    Causal inference in observational studies is notoriously difficult, due to the fact that the experimenter is not in charge of the treatment assignment mechanism. Many potential con- founding factors (PCFs) exist in such a scenario, and if one seeks to estimate the causal effect of the treatment on a response, one needs to control for such factors. Identifying all relevant PCFs may be difficult (or impossible) given a single observational study. Instead, we argue that if one can observe a sequ...

  1. Observer-based leader-following tracking control under both fixed and switching topologies

    Institute of Scientific and Technical Information of China (English)

    Jinhuan WANG; Pengxiao ZHANG; Zhixin LIU; Xiaoming HU

    2016-01-01

    This paper studies the tracking problem for a class of leader-follower multi-agent systems moving on the plane using observer-based cooperative control strategies. In our set-up, only a subset of the followers can obtain some relative information on the leader. We assume that the control input of the leader is not known to any of the followers while the system matrix is broadcast to all the followers. To track such a leader, an observer-based decentralized feedback controller is designed for each follower and detailed analysis for the convergence is presented for both fixed and switching interaction topologies between agents with the method of common Lyapunov function. We can also generalize the result to the higher dimension case for fixed topology and some special system matrices of the leader for switching topology.

  2. Ozone distributions over southern Lake Michigan: comparisons between ferry-based observations, shoreline-based DOAS observations and air quality forecast models

    Science.gov (United States)

    Cleary, P. A.; Fuhrman, N.; Schulz, L.; Schafer, J.; Fillingham, J.; Bootsma, H.; Langel, T.; Williams, E. J.; Brown, S. S.

    2014-09-01

    Air quality forecast models typically predict large ozone abundances over water relative to land in the Great Lakes region. While each state bordering Lake Michigan has dedicated monitoring systems, offshore measurements have been sparse, mainly executed through specific short-term campaigns. This study examines ozone abundances over Lake Michigan as measured on the Lake Express ferry, by shoreline Differential Optical Absorption Spectroscopy (DOAS) observations in southeastern Wisconsin, and as predicted by the National Air Quality Forecast System. From 2008-2009 measurements of O3, SO2, NO2 and formaldehyde were made in the summertime by DOAS at a shoreline site in Kenosha, WI. From 2008-2010 measurements of ambient ozone conducted on the Lake Express, a high-speed ferry that travels between Milwaukee, WI and Muskegon, MI up to 6 times daily from spring to fall. Ferry ozone observations over Lake Michigan were an average of 3.8 ppb higher than those measured at shoreline in Kenosha with little dependence on position of the ferry or temperature but with highest differences during evening and night. Concurrent ozone forecast images from National Weather System's National Air Quality Forecast System in the upper Midwestern region surrounding Lake Michigan were saved over the ferry ozone sampling period in 2009. The bias of the model O3 forecast was computed and evaluated with respect to ferry-based measurements. The model 1 and 8 h ozone mean biases were both 12 ppb higher than observed ozone, and maximum daily 1 h ozone mean bias was 10 ppb, indicating substantial ozone over-prediction over water. Trends in the bias with respect to location and time of day or month were also explored showing non-uniformity in model bias. Extreme ozone events were predicted by the model but not observed by ferry measurements.

  3. Health awareness and behavior among adolescent students in a rural school: a cross sectional observational study

    OpenAIRE

    Varshil Mehta; Anusha Bhat

    2015-01-01

    Background: Adolescents are particularly vulnerable to many health issues. Studies in Indian literature have documented low health awareness and many health related issues in adolescents. The aim and objective of the study was to evaluate health awareness and behavior among adolescents studying in a rural school in Maharashtra, India. Methods: A cross-sectional, quantitative, observational questionnaire-based survey was conducted among high school students between 15 to 19 years of age stu...

  4. A performance weighting procedure for GCMs based on explicit probabilistic models and accounting for observation uncertainty

    Science.gov (United States)

    Renard, Benjamin; Vidal, Jean-Philippe

    2016-04-01

    In recent years, the climate modeling community has put a lot of effort into releasing the outputs of multimodel experiments for use by the wider scientific community. In such experiments, several structurally distinct GCMs are run using the same observed forcings (for the historical period) or the same projected forcings (for the future period). In addition, several members are produced for a single given model structure, by running each GCM with slightly different initial conditions. This multiplicity of GCM outputs offers many opportunities in terms of uncertainty quantification or GCM comparisons. In this presentation, we propose a new procedure to weight GCMs according to their ability to reproduce the observed climate. Such weights can be used to combine the outputs of several models in a way that rewards good-performing models and discards poorly-performing ones. The proposed procedure has the following main properties: 1. It is based on explicit probabilistic models describing the time series produced by the GCMs and the corresponding historical observations, 2. It can use several members whenever available, 3. It accounts for the uncertainty in observations, 4. It assigns a weight to each GCM (all weights summing up to one), 5. It can also assign a weight to the "H0 hypothesis" that all GCMs in the multimodel ensemble are not compatible with observations. The application of the weighting procedure is illustrated with several case studies including synthetic experiments, simple cases where the target GCM output is a simple univariate variable and more realistic cases where the target GCM output is a multivariate and/or a spatial variable. These case studies illustrate the generality of the procedure which can be applied in a wide range of situations, as long as the analyst is prepared to make an explicit probabilistic assumption on the target variable. Moreover, these case studies highlight several interesting properties of the weighting procedure. In

  5. 2D vs. 3D mammography observer study

    Science.gov (United States)

    Fernandez, James Reza F.; Hovanessian-Larsen, Linda; Liu, Brent

    2011-03-01

    Breast cancer is the most common type of non-skin cancer in women. 2D mammography is a screening tool to aid in the early detection of breast cancer, but has diagnostic limitations of overlapping tissues, especially in dense breasts. 3D mammography has the potential to improve detection outcomes by increasing specificity, and a new 3D screening tool with a 3D display for mammography aims to improve performance and efficiency as compared to 2D mammography. An observer study using a mammography phantom was performed to compare traditional 2D mammography with this ne 3D mammography technique. In comparing 3D and 2D mammography there was no difference in calcification detection, and mass detection was better in 2D as compared to 3D. There was a significant decrease in reading time for masses, calcifications, and normals in 3D compared to 2D, however, as well as more favorable confidence levels in reading normal cases. Given the limitations of the mammography phantom used, however, a clearer picture in comparing 3D and 2D mammography may be better acquired with the incorporation of human studies in the future.

  6. Study of the NWC electrons belt observed on DEMETER Satellite

    CERN Document Server

    Li, Xinqiao; Wang, Ping; Wang, Huanyu; Lu, Hong; Zhang, Xuemin; Huang, Jianping; Shi, Feng; Yu, Xiaoxia; Xu, Yanbing; Meng, Xiangcheng; Wang, Hui; Zhao, Xiaoyun; Parrot, M

    2010-01-01

    We analyzed the data from 2007 to 2008, which is observed by IDP onboard DEMETER satellite, during ten months of NWC working and seven months of NWC shutdown. The characteristic of the space instantaneous electron belts, which come from the influence of the VLF transmitted by NWC, is studied comprehensively. The main distribution region of the NWC electron belts and the flux change are given. We also studied the distribution characteristic of the average energy spectrum in different magnetic shell at the height of DEMETER orbit and the difference of the average energy spectrum of the electrons in the drift loss-cone between day and night. As a result, the powerful power of NWC transmitter and the 19.8 kHz narrow bandwidth VLF emission not only created a momentary electrons enhancement region, which strides 180 degree in them longitude direction and from 1.6 to 1.9 in L value, with the rise of the electrons flux reaching to 3 orders of magnitude mostly, but also induced the enhancement or loss of electrons in ...

  7. An Observational Study of Pulsations in Proto-Planetary Nebulae

    Science.gov (United States)

    Hrivnak, Bruce J.; Lu, Wenxian; Henson, Gary D.; Hillwig, Todd C.

    2016-01-01

    We have been carrying out a long-term monitoring program to study the light variability in proto-planetary nebulae (PPNe). PPNe are post-Asymptotic Giant Branch objects in transition between the AGB and PN phases in the evolution of low and intermediate-mass stars. As such, it is not surprising that they display pulsational variability. We have been carrying out photometric monitoring of 30 of these at the Valparaiso University campus observatory over the last 20 years, with the assistance of undergraduate students. The sample size has been enlarged over the past six years by observations made using telescopes in the SARA consortium at KPNO and CTIO. Periods have been determined for those of F-G spectral types. We have also enlarged the sample with PPNe from outside the Milky Way by determining periods of eight PPNe in the lower metalicity environment of the Magellanic Clouds. Periods for the entire sample range from 35 to 160 days. Some clear patterns have emerged, with those of higher temperature possessing shorter periods and smaller amplitudes, indicating a reduction in period and pulsation amplitude as the objects evolve. Radial velocity monitoring of several of the brightest of these has allowed us to document their changes in brightness, color, and size during a pulsation cycle. The results of this study will be presented. This research is supported by grants from the National Science Foundation (most recently AST 1413660), with additional student support from the Indiana Space Grant Consortium.

  8. Attenuation of disturbances introduced by dynamic links in precision motion systems using model-based observers

    OpenAIRE

    Hoogerkamp, M.; Waiboer, R.R.; Dijk, van, B.W.; Aarts, R.G.K.M.

    2014-01-01

    This paper presents an extension to the Unknown Input Disturbance Observer (UIDO) and the Disturbance Estimation Filter (DEF). This extension enables the inclusion of the mechanics of dynamic links to the observer model, in order to attenuate the specific disturbances introduced by those dynamic links. A design method of the state space feedback gain based on the dynamics, and an observer gain based on basic Kalman filter theory is given. It is shown how the observer is designed for a practic...

  9. Assessing distractors and teamwork during surgery: developing an event-based method for direct observation

    OpenAIRE

    Seelandt, J. C.; Tschan, Franziska; Keller, S.; Beldi, Guido; Jenni, N.; Kurmann, Anita; Candinas, Daniel; Semmer, Norbert

    2014-01-01

    OBJECTIVE: To develop a behavioural observation method to simultaneously assess distractors and communication/teamwork during surgical procedures through direct, on-site observations; to establish the reliability of the method for long (>3 h) procedures. METHODS: Observational categories for an event-based coding system were developed based on expert interviews, observations and a literature review. Using Cohen's κ and the intraclass correlation coefficient, interobserver agreem...

  10. Inverse Modeling of Texas NOx Emissions Using Space-Based and Ground-Based NO2 Observations

    Science.gov (United States)

    Tang, Wei; Cohan, D.; Lamsal, L. N.; Xiao, X.; Zhou, W.

    2013-01-01

    Inverse modeling of nitrogen oxide (NOx) emissions using satellite-based NO2 observations has become more prevalent in recent years, but has rarely been applied to regulatory modeling at regional scales. In this study, OMI satellite observations of NO2 column densities are used to conduct inverse modeling of NOx emission inventories for two Texas State Implementation Plan (SIP) modeling episodes. Addition of lightning, aircraft, and soil NOx emissions to the regulatory inventory narrowed but did not close the gap between modeled and satellite observed NO2 over rural regions. Satellitebased top-down emission inventories are created with the regional Comprehensive Air Quality Model with extensions (CAMx) using two techniques: the direct scaling method and discrete Kalman filter (DKF) with Decoupled Direct Method (DDM) sensitivity analysis. The simulations with satellite-inverted inventories are compared to the modeling results using the a priori inventory as well as an inventory created by a ground-level NO2 based DKF inversion. The DKF inversions yield conflicting results: the satellite based inversion scales up the a priori NOx emissions in most regions by factors of 1.02 to 1.84, leading to 3-55% increase in modeled NO2 column densities and 1-7 ppb increase in ground 8 h ozone concentrations, while the ground-based inversion indicates the a priori NOx emissions should be scaled by factors of 0.34 to 0.57 in each region. However, none of the inversions improve the model performance in simulating aircraft-observed NO2 or ground-level ozone (O3) concentrations.

  11. A LEKID-based CMB instrument design for large-scale observations in Greenland

    CERN Document Server

    Araujo, D C; Bond, J R; Bradford, K J; Chapman, D; Che, G; Day, P K; Didier, J; Doyle, S; Eriksen, H K; Flanigan, D; Groppi, C E; Hillbrand, S N; Johnson, B R; Jones, G; Limon, M; Miller, A D; Mauskopf, P; McCarrick, H; Mroczkowski, T; Reichborn-Kjennerud, B; Smiley, B; Sobrin, J; Wehus, I K; Zmuidzinas, J

    2014-01-01

    We present the results of a feasibility study, which examined deployment of a ground-based millimeter-wave polarimeter, tailored for observing the cosmic microwave background (CMB), to Isi Station in Greenland. The instrument for this study is based on lumped-element kinetic inductance detectors (LEKIDs) and an F/2.4 catoptric, crossed-Dragone telescope with a 500 mm aperture. The telescope is mounted inside the receiver and cooled to $<\\,4$ K by a closed-cycle $^4$He refrigerator to reduce background loading on the detectors. Linearly polarized signals from the sky are modulated with a metal-mesh half-wave plate that is rotated at the aperture stop of the telescope with a hollow-shaft motor based on a superconducting magnetic bearing. The modular detector array design includes at least 2300 LEKIDs, and it can be configured for spectral bands centered on 150~GHz or greater. Our study considered configurations for observing in spectral bands centered on 150, 210 and 267~GHz. The entire polarimeter is mounte...

  12. Estimation of nonfluctuating reservoir inflow from water level observations using methods based on flow continuity

    Science.gov (United States)

    Deng, Chao; Liu, Pan; Guo, Shenglian; Wang, Hao; Wang, Dingbao

    2015-10-01

    The accurate estimation of "true" reservoir inflow is important for hydrological forecasting and efficient operation of reservoirs. However, reservoir inflow estimated using the conventional simple water balance method is not always accurate because the estimation is very sensitive to errors in reservoir water level observations and uncertainty in the stage-storage relationship. An analytical method (AM) and a method using the ensemble Kalman filter (EnKF) are proposed to determine nonfluctuating reservoir inflow based on the concept of inflow continuity; that is, that inflow should not change much within a short time period. The AM is developed based on the simultaneous minimization of both the estimated reservoir water level error and the inflow variation. The EnKF, which is built on state equations (inflow continuity and water balance equations) and an observation equation (the reservoir stage-storage relationship), is used to update inflow states by assimilating water level observations. The two proposed methods are evaluated using a synthetic experiment with various conditions including water level observation error, reservoir stage-storage relationship error, and the influence of water surface slope. The AM outperforms the EnKF under all conditions. Case studies of the Gaobazhou and Danjiangkou Reservoirs in China demonstrate that both of the proposed methods can derive an hourly inflow without fluctuations. The results indicate that the AM and the EnKF method can improve reservoir inflow estimation compared with conventional methods.

  13. Observational study of sites of triggered star formation: CO and mid-infrared observations

    CERN Document Server

    Urquhart, J S; Thompson, M A

    2009-01-01

    (Abridged) Bright-rimmed clouds (BRCs) are isolated molecular clouds located on the edges of evolved HII regions where star formation is thought may have been triggered. In this paper we investigate the current level of star formation within a sample of BRCs and evaluate to what extent star formation may have been induced. We present the results of a programme of position-switched CO observations towards 45 southern BRCs. The 12CO, 13CO and C18O (J=1-0) were simultaneously observed using the 22m Mopra telescope. We complement these observations with archival mid-IR submm and radio data. Analysis of the CO, mid-IR and radio data result in the clouds being divided into three distinct groups. We refer to these groups as spontaneous, triggered, and zapped clouds, respectively. Comparing the physical parameters of spontaneous and triggered samples we find striking differences in luminosity, surface temperature and column density with all three quantities significantly enhanced for the clouds considered to have bee...

  14. Analysis of visibility simulation of three polar regions from lunar-based earth observation

    Science.gov (United States)

    Ye, Hanlin; Liu, Guang; Ren, Yuanzhen; Guo, Huadong; Ding, Yixing

    2016-07-01

    Global environment change has caught the attention of many scientists around the world. The Arctic, Antarctic and Tibet Plateau are known as the three polar regions. They are the world's largest storage of cold and carbon which are the sensitive regions of global environment change. These three regions have significant impacts on the global environment change. It is extremely obvious that the environment change of these three regions is one of the major factors of global environment change. The special geographical positions of these three regions have great influence on the local climate and ecological environment that caused the climate is very bad and few people can get there, so there is very little observation data exists. In addition, these three regions have large scale and long-term observation characteristics. Since the meaning of remote sensing technology came out, we have developed airborne and space-borne Earth observation system. However, when taking three polar regions for researching, we will have to face the problems of temporal coherence and spatial continuity in the global scale, which challenges the Earth observation on the satellite and airborne platform. Moon is the unique natural satellite of the Earth, which always has one side facing it, with the advantages of large coverage, long-life platform, stable geological structure and multi-spheres three-dimensional detecting, turning out to be the ideal platform for observing three polar regions. At present and in the near future, the study of Earth observation data from a lunar observatory would be difficult to carry out, so a simulation is used in this paper to analyze the visibility of three polar regions. At first, we discuss the motion pattern of the Sun-Earth-Moon system. Then we construct a simulation system with simulated optical sensors setting up at different places on the Moon, finding that sunlight has great influence on optical observation. The visible region of a lunar-based optical

  15. Testing Gravitational Physics with Space-based Gravitational-wave Observations

    Science.gov (United States)

    Baker, John G.

    2011-01-01

    Gravitational wave observations provide exceptional and unique opportunities for precision tests of gravitational physics, as predicted by general relativity (GR). Space-based gravitational wave measurements, with high signal-to-noise ratios and large numbers of observed events may provide the best-suited gravitational-wave observations for testing GR with unprecedented precision. These observations will be especially useful in testing the properties of gravitational waves and strong-field aspects of the theory which are less relevant in other observations. We review the proposed GR test based on observations of massive black hole mergers, extreme mass ratio inspirals, and galactic binary systems.

  16. Initial Validation of the Prekindergarten Classroom Observation Tool and Goal Setting System for Data-Based Coaching

    Science.gov (United States)

    Crawford, April D.; Zucker, Tricia A.; Williams, Jeffrey M.; Bhavsar, Vibhuti; Landry, Susan H.

    2013-01-01

    Although coaching is a popular approach for enhancing the quality of Tier 1 instruction, limited research has addressed observational measures specifically designed to focus coaching on evidence-based practices. This study explains the development of the prekindergarten (pre-k) Classroom Observation Tool (COT) designed for use in a data-based…

  17. Patient satisfaction concerning implant-supported prostheses: an observational study

    Directory of Open Access Journals (Sweden)

    Bruno César de Vasconcelos GURGEL

    2015-01-01

    Full Text Available The aim of this observational study was to assess the degree of patient satisfaction toward implant-supported prostheses. A questionnaire was used with two scales (one consisting of detailed adjectival and the other of numerical responses regarding chewing, esthetics, speaking, comfort and overall satisfaction. The scales were administered to a sample of 147 patients treated with implants and prostheses. The data were submitted to the Kappa statistic and the Chi-square test to analyze the association between dependent and independent variables. High degrees of satisfaction (greater than 91% were found for all categories evaluated, regardless of gender, age, number of implants or type of prosthesis. “Comfort” was associated significantly with the number of implants (p = 0.038, and “speaking” was associated significantly with the type of prosthesis (p = 0.029. Positive agreement was found between the scales for all categories evaluated, without statistically significant differences regarding respondent preference (p = 0.735. Patients treated with implant-supported prostheses were highly satisfied with the treatment.

  18. Fatal poisonings in Oslo: a one-year observational study

    Directory of Open Access Journals (Sweden)

    Heyerdahl Fridtjof

    2010-06-01

    Full Text Available Abstract Background Acute poisonings are common and are treated at different levels of the health care system. Since most fatal poisonings occur outside hospital, these must be included when studying characteristics of such deaths. The pattern of toxic agents differs between fatal and non-fatal poisonings. By including all poisoning episodes, cause-fatality rates can be calculated. Methods Fatal and non-fatal acute poisonings in subjects aged ≥16 years in Oslo (428 198 inhabitants were included consecutively in an observational multi-centre study including the ambulance services, the Oslo Emergency Ward (outpatient clinic, and hospitals, as well as medico-legal autopsies from 1st April 2003 to 31st March 2004. Characteristics of fatal poisonings were examined, and a comparison of toxic agents was made between fatal and non-fatal acute poisoning. Results In Oslo, during the one-year period studied, 103 subjects aged ≥16 years died of acute poisoning. The annual mortality rate was 24 per 100 000. The male-female ratio was 2:1, and the mean age was 44 years (range 19-86 years. In 92 cases (89%, death occurred outside hospital. The main toxic agents were opiates or opioids (65% of cases, followed by ethanol (9%, tricyclic anti-depressants (TCAs (4%, benzodiazepines (4%, and zopiclone (4%. Seventy-one (69% were evaluated as accidental deaths and 32 (31% as suicides. In 70% of all cases, and in 34% of suicides, the deceased was classified as drug or alcohol dependent. When compared with the 2981 non-fatal acute poisonings registered during the study period, the case fatality rate was 3% (95% C.I., 0.03-0.04. Methanol, TCAs, and antihistamines had the highest case fatality rates; 33% (95% C.I., 0.008-0.91, 14% (95% C.I., 0.04-0.33, and 10% (95% C.I., 0.02-0.27, respectively. Conclusions Three per cent of all acute poisonings were fatal, and nine out of ten deaths by acute poisonings occurred outside hospital. Two-thirds were evaluated as accidental

  19. Estimating Total Discharge in the Yangtze River Basin Using Satellite-Based Observations

    Directory of Open Access Journals (Sweden)

    Samuel A. Andam‑Akorful

    2013-07-01

    Full Text Available The measurement of total basin discharge along coastal regions is necessary for understanding the hydrological and oceanographic issues related to the water and energy cycles. However, only the observed streamflow (gauge-based observation is used to estimate the total fluxes from the river basin to the ocean, neglecting the portion of discharge that infiltrates to underground and directly discharges into the ocean. Hence, the aim of this study is to assess the total discharge of the Yangtze River (Chang Jiang basin. In this study, we explore the potential response of total discharge to changes in precipitation (from the Tropical Rainfall Measuring Mission—TRMM, evaporation (from four versions of the Global Land Data Assimilation—GLDAS, namely, CLM, Mosaic, Noah and VIC, and water-storage changes (from the Gravity Recovery and Climate Experiment—GRACE by using the terrestrial water budget method. This method has been validated by comparison with the observed streamflow, and shows an agreement with a root mean square error (RMSE of 14.30 mm/month for GRACE-based discharge and 20.98 mm/month for that derived from precipitation minus evaporation (P − E. This improvement of approximately 32% indicates that monthly terrestrial water-storage changes, as estimated by GRACE, cannot be considered negligible over Yangtze basin. The results for the proposed method are more accurate than the results previously reported in the literature.

  20. ESTIMATION OF S-WAVE VELOCITY STRUCTURE OF FUKUI PLAIN BASED ON MICROTREMOR ARRAY OBSERVATION

    Science.gov (United States)

    Kojima, Keisuke; Moto, Koudai

    The precise evaluations of Quaternary structure of the region are indispensable in order to accurately predict the seismic damage. However, deep borehole, PS-logging and elastic wave exploration have been executed only on limited points around the Fukui Plain. The problem analyzed in this study is statistical estimation of the 3D S-wave velocity structure down to the Tertiary bedrock of the Fukui Plain based on the data from 75 microtremor array observation sites. The Rayleigh wave phase velocities at each array site were calculated by the spatial autocorrelation method. The phase velocities at each site were inverted to a 1D S-wave profile using a genetic inversion. The 3-components single-site microtremor observations were carried out to compensate the array observations. The 3D S-wave velocity structure around the Fukui plain have been interpolated by using Kriging and Co-Kriging techniques. In the Co-Kriging procedure, the correlations between the estimated depths of Quaternary and the observed predominant periods of the sites were taken into account. The validity of the estimated structure from the microtremor observation was confirmed by comparing with the density structure and with the existing PS-logging data.

  1. Ground-based observations of overshooting convection during the Tropical Warm Pool-International Cloud Experiment

    Science.gov (United States)

    Hassim, M. E. E.; Lane, T. P.; May, P. T.

    2014-01-01

    This study uses gridded radar data to investigate the properties of deep convective storms that penetrate the tropical tropopause layer (TTL) and overshoot the cold-point tropopause during the Tropical Warm Pool-International Cloud Experiment (TWP-ICE). Overshooting convection during the observed break period is relatively more intense and exhibits lesser diurnal variability than severe monsoonal storms in terms of mean overshooting area in the TTL (as covered by >20 dBZ echoes). However, ground-based radar has geometrical constraints and sampling gaps at high altitude that lead to biases in the final radar product. Using synthetic observations derived from model-based data, ground-based radar is shown to underestimate the mean overshooting area in the TTL across both TWP-ICE regimes. Differences range from ˜180 km2 (˜100 km2) to ˜14 km2 (˜8 km2) between 14 and 18 km for the active (break) period. This implies that the radar is underestimating the transport of water and ice mass into the TTL by convective overshoots during TWP-ICE. The synthetic data is also used to correct profiles of the mean observed overshooting area. These are shown to differ only marginally between the two sampled regimes once the influence of a large mesoscale convective system, considered as a departure from normal monsoon behavior, was removed from the statistics. The results of our study provide a useful cross-validation comparison for satellite-based detections of overshooting top areas over Darwin, Australia.

  2. Observing power blackouts from space - A disaster related study

    Science.gov (United States)

    Aubrecht, C.; Elvidge, C. D.; Ziskin, D.; Baugh, K. E.; Tuttle, B.; Erwin, E.; Kerle, N.

    2009-04-01

    In case of emergency disaster managers worldwide require immediate information on affected areas and estimations of the number of affected people. Natural disasters such as earthquakes, hurricanes, tornados, wind and ice storms often involve failures in the electrical power generation system and grid. Near real time identification of power blackouts gives a first impression of the area affected by the event (Elvidge et al. 2007), which can subsequently be linked to population estimations. Power blackouts disrupt societal activities and compound the difficulties associated with search and rescue, clean up, and the provision of food and other supplies following a disastrous event. Locations and spatial extents of power blackouts are key considerations in planning and execution of the primary disaster missions of emergency management organizations. To date only one satellite data source has been used successfully for the detection of power blackouts. Operated by NOAA's National Geophysical Data Center (NGDC) the U.S. Air Force Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) offers a unique capability to observe lights present at the Earth's surface at night. Including a pair of visible and thermal spectral bands and originally designed to detect moonlit clouds, this sensor enables mapping of lights from cities and towns, gas flares and offshore platforms, fires, and heavily lit fishing boats. The low light imaging of the OLS is accomplished using a photomultiplier tube (PMT) which intensifies the visible band signal at night. With 14 orbits collected per day and a 3.000 km swath width, each OLS is capable of collecting a complete set of images of the Earth every 24 hours. NGDC runs the long-term archive for OLS data with the digital version extending back to 1992. OLS data is received by NGDC in near real time (1-2 hours from acquisition) and subscription based services for the near real time data are provided for users all over the

  3. Tree survival and maximum density of planted forests – Observations from South African spacing studies

    OpenAIRE

    Gadow, Klaus V.; Heyns Kotze

    2014-01-01

    Background Among the most important aspects of risk and hazard studies relating to forest ecosystems are maximum forest density and density-dependent tree survival. Methods Long-term observations about the maximum density of unthinned Pinus patula and P. elliottii field plots based on the Correlated Curve Trend (CCT) spacing studies which were established almost 8 decades ago by O’Connor (Forest Research with Special Reference to Planting Distances and Thinning, 1935) in South Afric...

  4. Value of fecal calprotectin in the evaluation of patients with abdominal discomfort: an observational study

    OpenAIRE

    Manz Michael; Burri Emanuel; Rothen Claude; Tchanguizi Nuschin; Niederberger Christian; Rossi Livio; Beglinger Christoph; Lehmann Frank

    2012-01-01

    Abstract Background The evaluation of patients with abdominal discomfort is challenging and patient selection for endoscopy based on symptoms is not reliable. We evaluated the diagnostic value of fecal calprotectin in patients with abdominal discomfort. Methods In an observational study, 575 consecutive patients with abdominal discomfort referred for endoscopy to the Department of Gastroenterology & Hepatology at the University Hospital Basel in Switzerland, were enrolled in the study. Calpro...

  5. ARCADO - Adding random case analysis to direct observation in workplace-based formative assessment of general practice registrars

    OpenAIRE

    Ingham, Gerard; Fry, Jennifer; Morgan, Simon; Ward, Bernadette

    2015-01-01

    Background Workplace-based formative assessments using consultation observation are currently conducted during the Australian general practice training program. Assessment reliability is improved by using multiple assessment methods. The aim of this study was to explore experiences of general practice medical educator assessors and registrars (trainees) when adding random case analysis to direct observation (ARCADO) during formative workplace-based assessments. Methods A sample of general pra...

  6. Contribution of amateur observations to Saturn storm studies

    CERN Document Server

    Delcroix, Marc

    2010-01-01

    Since 2004, Saturn Electrostatic Discharges (SEDs), which are the radio signatures of lightning in Saturn's atmosphere, have been observed by the Cassini Radio and Plasma Wave Science instrument (RPWS). Despite their important time coverage, these observations lack the resolution and positioning given by imaging around visible wavelengths. Amateur observations from Earth have been increasing in quality and coverage since a few years, bringing information on positions, drift rates and shape evolutions of large visible white spots in Saturn's atmosphere. Combining these two complementary sources has brought better analysis of Saturn's storms evolutions.

  7. Impact on Medical Cost, Cumulative Survival, and Cost-Effectiveness of Adding Rituximab to First-Line Chemotherapy for Follicular Lymphoma in Elderly Patients: An Observational Cohort Study Based on SEER-Medicare

    Directory of Open Access Journals (Sweden)

    Robert I. Griffiths

    2012-01-01

    Full Text Available Rituximab improves survival in follicular lymphoma (FL, but is considerably more expensive than conventional chemotherapy. We estimated the total direct medical costs, cumulative survival, and cost-effectiveness of adding rituximab to first-line chemotherapy for FL, based on a single source of data representing routine practice in the elderly. Using surveillance, epidemiology, and end results (SEER registry data plus Medicare claims, we identified 1,117 FL patients who received first-line CHOP (cyclophosphamide (C, doxorubicin, vincristine (V, and prednisone (P or CVP +/− rituximab. Multivariate regression was used to estimate adjusted cumulative cost and survival differences between the two groups over four years after beginning treatment. The median age was 73 years (minimum 66 years, 56% had stage III-IV disease, and 67% received rituximab. Adding rituximab to first-line chemotherapy was associated with higher adjusted incremental total cost ($18,695; 95% Confidence Interval (CI $9,302–$28,643 and longer adjusted cumulative survival (0.18 years; 95% CI 0.10–0.27 over four years of followup. The expected cost-effectiveness was $102,142 (95% CI $34,531–296,337 per life-year gained. In routine clinical practice, adding rituximab to first-line chemotherapy for elderly patients with FL results in higher direct medical costs to Medicare and longer cumulative survival after four years.

  8. Water and sodium intake habits and status of ultra-endurance runners during a multi-stage ultra-marathon conducted in a hot ambient environment: an observational field based study

    Directory of Open Access Journals (Sweden)

    Costa Ricardo JS

    2013-01-01

    Full Text Available Abstract Background Anecdotal evidence suggests ultra-runners may not be consuming sufficient water through foods and fluids to maintenance euhydration, and present sub-optimal sodium intakes, throughout multi-stage ultra-marathon (MSUM competitions in the heat. Subsequently, the aims were primarily to assess water and sodium intake habits of recreational ultra-runners during a five stage 225 km semi self-sufficient MSUM conducted in a hot ambient environment (Tmax range: 32°C to 40°C; simultaneously to monitor serum sodium concentration, and hydration status using multiple hydration assessment techniques. Methods Total daily, pre-stage, during running, and post-stage water and sodium ingestion of ultra-endurance runners (UER, n = 74 and control (CON, n = 12 through foods and fluids were recorded on Stages 1 to 4 by trained dietetic researchers using dietary recall interview technique, and analysed through dietary analysis software. Body mass (BM, hydration status, and serum sodium concentration were determined pre- and post-Stages 1 to 5. Results Water (overall mean (SD: total daily 7.7 (1.5 L/day, during running 732 (183 ml/h and sodium (total daily 3.9 (1.3 g/day, during running 270 (151 mg/L ingestion did not differ between stages in UER (p vs. CON. Exercise-induced BM loss was 2.4 (1.2% (p p > 0.05 vs. CON pre-stage. Asymptomatic hyponatraemia (n = 8 UER, corresponding to 42% of sampled participants. Pre- and post-stage urine colour, urine osmolality and urine/plasma osmolality ratio increased (p p  Conclusion Water intake habits of ultra-runners during MSUM conducted in hot ambient conditions appear to be sufficient to maintain baseline euhydration levels. However, fluid over-consumption behaviours were evident along competition, irrespective of running speed and gender. Normonatraemia was observed in the majority of ultra-runners throughout MSUM, despite sodium ingestion under benchmark recommendations.

  9. Some observations on phosphate based corrosion inhibitors in preventing carbon steel corrosion

    International Nuclear Information System (INIS)

    Among the various types of phosphonic acid based inhibitors assayed, namely HEDP, ATMP and a commercial corrosion inhibitor (code named Betz), it was found that Betz has the maximum amount of organic phosphate followed by HEDP and ATMP. The corrosion rate studies show that Betz gives the highest inhibition efficiency followed by HEDP and ATMP. This shows that organic phosphate plays a significant role in corrosion protection. However, it was observed that due to synergestic effect, HEDP in the presence of Zn2+ gave a better corrosion protection than Betz. The results are discussed in the light of available literature. (author)

  10. Adaptive observer based synchronization of a class of uncertain chaotic systems

    International Nuclear Information System (INIS)

    This study addresses the adaptive synchronization of a class of uncertain chaotic systems in the drive-response framework. For a class of uncertain chaotic systems with unknown parameters and external disturbances, a robust adaptive observer based response system is constructed to synchronize the uncertain chaotic system. Lyapunov stability theory and Barbalat lemma ensure the global synchronization between the drive and response systems even if Lipschitz constants on function matrices and bounds on uncertainties are unknown. Numerical simulation of the Genesio-Tesi system verifies the effectiveness of the proposed method. (author)

  11. Fathers and breast feeding: a pilot observational study.

    Science.gov (United States)

    Voss, S; Finnis, L; Manners, J

    1993-08-01

    A small pilot survey (n = 113) by questionnaire of the fathers of a sample of children under one year of age was undertaken in order to investigate the involvement of fathers with infant feeding and their attitudes to the method of feeding adopted. The response rate was 72% overall and 79% when the partners of 'single parent' mothers were excluded. Nearly 30% of respondents had not discussed the method of feeding with anyone, but over 60% had discussed it with their partner. 64% of fathers sometimes helped with feeding their child and 17% said that they always helped. The majority of fathers did not mind their partner breast feeding in front of friends or relatives but 42% did not like them feeding in front of strangers and over half did not like them breast feeding in a public place. From this study, based on relatively small numbers, we conclude that fathers may feel left out of infant feeding. They should be given more opportunity to become involved from an early stage and take part in the decision about the method of infant feeding to be adopted. PMID:8410907

  12. Computational and human observer image quality evaluation of low dose, knowledge-based CT iterative reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Eck, Brendan L.; Fahmi, Rachid; Miao, Jun [Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio 44106 (United States); Brown, Kevin M.; Zabic, Stanislav; Raihani, Nilgoun [Philips Healthcare, Cleveland, Ohio 44143 (United States); Wilson, David L., E-mail: dlw@case.edu [Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio 44106 and Department of Radiology, Case Western Reserve University, Cleveland, Ohio 44106 (United States)

    2015-10-15

    Purpose: Aims in this study are to (1) develop a computational model observer which reliably tracks the detectability of human observers in low dose computed tomography (CT) images reconstructed with knowledge-based iterative reconstruction (IMR™, Philips Healthcare) and filtered back projection (FBP) across a range of independent variables, (2) use the model to evaluate detectability trends across reconstructions and make predictions of human observer detectability, and (3) perform human observer studies based on model predictions to demonstrate applications of the model in CT imaging. Methods: Detectability (d′) was evaluated in phantom studies across a range of conditions. Images were generated using a numerical CT simulator. Trained observers performed 4-alternative forced choice (4-AFC) experiments across dose (1.3, 2.7, 4.0 mGy), pin size (4, 6, 8 mm), contrast (0.3%, 0.5%, 1.0%), and reconstruction (FBP, IMR), at fixed display window. A five-channel Laguerre–Gauss channelized Hotelling observer (CHO) was developed with internal noise added to the decision variable and/or to channel outputs, creating six different internal noise models. Semianalytic internal noise computation was tested against Monte Carlo and used to accelerate internal noise parameter optimization. Model parameters were estimated from all experiments at once using maximum likelihood on the probability correct, P{sub C}. Akaike information criterion (AIC) was used to compare models of different orders. The best model was selected according to AIC and used to predict detectability in blended FBP-IMR images, analyze trends in IMR detectability improvements, and predict dose savings with IMR. Predicted dose savings were compared against 4-AFC study results using physical CT phantom images. Results: Detection in IMR was greater than FBP in all tested conditions. The CHO with internal noise proportional to channel output standard deviations, Model-k4, showed the best trade-off between fit

  13. Computational and human observer image quality evaluation of low dose, knowledge-based CT iterative reconstruction

    International Nuclear Information System (INIS)

    Purpose: Aims in this study are to (1) develop a computational model observer which reliably tracks the detectability of human observers in low dose computed tomography (CT) images reconstructed with knowledge-based iterative reconstruction (IMR™, Philips Healthcare) and filtered back projection (FBP) across a range of independent variables, (2) use the model to evaluate detectability trends across reconstructions and make predictions of human observer detectability, and (3) perform human observer studies based on model predictions to demonstrate applications of the model in CT imaging. Methods: Detectability (d′) was evaluated in phantom studies across a range of conditions. Images were generated using a numerical CT simulator. Trained observers performed 4-alternative forced choice (4-AFC) experiments across dose (1.3, 2.7, 4.0 mGy), pin size (4, 6, 8 mm), contrast (0.3%, 0.5%, 1.0%), and reconstruction (FBP, IMR), at fixed display window. A five-channel Laguerre–Gauss channelized Hotelling observer (CHO) was developed with internal noise added to the decision variable and/or to channel outputs, creating six different internal noise models. Semianalytic internal noise computation was tested against Monte Carlo and used to accelerate internal noise parameter optimization. Model parameters were estimated from all experiments at once using maximum likelihood on the probability correct, PC. Akaike information criterion (AIC) was used to compare models of different orders. The best model was selected according to AIC and used to predict detectability in blended FBP-IMR images, analyze trends in IMR detectability improvements, and predict dose savings with IMR. Predicted dose savings were compared against 4-AFC study results using physical CT phantom images. Results: Detection in IMR was greater than FBP in all tested conditions. The CHO with internal noise proportional to channel output standard deviations, Model-k4, showed the best trade-off between fit and

  14. A Mechanical Study of a Glass Fabric-Thermoplastic Resin Composite: 3D-DIC and X-ray tomographic observations explained by numerical simulations based on a spectral solver

    CERN Document Server

    Boufaida, Zakariya; André, Stéphane; Farge, Laurent

    2016-01-01

    In the study presented in this paper, we analyzed the mechanical response of a glass fiber plain weave/polymer composite at the fabric millimetric mesoscale. The detail of the stress and strain fields in a fabric repeating unit cell was numerically calculated using CraFT (Composite response and Fourier Transforms), a code specifically conceived for simulating the mechanical behaviour of materials with complex microstructure. The local strain fields obtained by simulation were found to be in very good agreement with measurements carried out using 3D Digital Image Correlation (3D DIC). From numerical stress fields calculated with the CraFT solver, we also highlighted the subregions inside the periodic mesostructure where there is maximum stress. Furthermore, with X-ray tomography post mortem measurements, we were able to confirm that certain damage modes were well initiated in these microstructure subregions of stress concentration.

  15. Subtropical and Polar Cirrus Clouds Characterized by Ground-Based Lidars and CALIPSO/CALIOP Observations

    Directory of Open Access Journals (Sweden)

    Córdoba-Jabonero Carmen

    2016-01-01

    Full Text Available Cirrus clouds are product of weather processes, and then their occurrence and macrophysical/optical properties can vary significantly over different regions of the world. Lidars can provide height-resolved measurements with a relatively good both vertical and temporal resolutions, making them the most suitable instrumentation for high-cloud observations. The aim of this work is to show the potential of lidar observations on Cirrus clouds detection in combination with a recently proposed methodology to retrieve the Cirrus clouds macrophysical and optical features. In this sense, a few case studies of cirrus clouds observed at both subtropical and polar latitudes are examined and compared to CALIPSO/CALIOP observations. Lidar measurements are carried out in two stations: the Metropolitan city of Sao Paulo (MSP, Brazil, 23.3°S 46.4°W, located at subtropical latitudes, and the Belgrano II base (BEL, Argentina, 78ºS 35ºW in the Antarctic continent. Optical (COD-cloud optical depth and LR-Lidar Ratio and macrophysical (top/base heights and thickness properties of both the subtropical and polar cirrus clouds are reported. In general, subtropical Cirrus clouds present lower LR values and are found at higher altitudes than those detected at polar latitudes. In general, Cirrus clouds are detected at similar altitudes by CALIOP. However, a poor agreement is achieved in the LR retrieved between ground-based lidars and space-borne CALIOP measurements, likely due to the use of a fixed (or low-variable LR value in CALIOP inversion procedures.

  16. Subtropical and Polar Cirrus Clouds Characterized by Ground-Based Lidars and CALIPSO/CALIOP Observations

    Science.gov (United States)

    Córdoba-Jabonero, Carmen; Lopes, Fabio J. S.; Landulfo, Eduardo; Ochoa, Héctor; Gil-Ojeda, Manuel

    2016-06-01

    Cirrus clouds are product of weather processes, and then their occurrence and macrophysical/optical properties can vary significantly over different regions of the world. Lidars can provide height-resolved measurements with a relatively good both vertical and temporal resolutions, making them the most suitable instrumentation for high-cloud observations. The aim of this work is to show the potential of lidar observations on Cirrus clouds detection in combination with a recently proposed methodology to retrieve the Cirrus clouds macrophysical and optical features. In this sense, a few case studies of cirrus clouds observed at both subtropical and polar latitudes are examined and compared to CALIPSO/CALIOP observations. Lidar measurements are carried out in two stations: the Metropolitan city of Sao Paulo (MSP, Brazil, 23.3°S 46.4°W), located at subtropical latitudes, and the Belgrano II base (BEL, Argentina, 78ºS 35ºW) in the Antarctic continent. Optical (COD-cloud optical depth and LR-Lidar Ratio) and macrophysical (top/base heights and thickness) properties of both the subtropical and polar cirrus clouds are reported. In general, subtropical Cirrus clouds present lower LR values and are found at higher altitudes than those detected at polar latitudes. In general, Cirrus clouds are detected at similar altitudes by CALIOP. However, a poor agreement is achieved in the LR retrieved between ground-based lidars and space-borne CALIOP measurements, likely due to the use of a fixed (or low-variable) LR value in CALIOP inversion procedures.

  17. Ground-Based Network and Supersite Observations to Complement and Enrich EOS Research

    Science.gov (United States)

    Tsay, Si-Chee; Holben, Brent N.; Welton, Ellsworth J.

    2011-01-01

    Since 1997 NASA has been successfully launching a series of satellites - the Earth Observing System (EOS) - to intensively study, and gain a better understanding of, the Earth as an integrated system. Space-borne remote sensing observations, however, are often plagued by contamination of surface signatures. Thus, ground-based in-situ and remote-sensing measurements, where signals come directly from atmospheric constituents, the sun, and/or the Earth-atmosphere interactions, provide additional information content for comparisons that confirm quantitatively the usefulness of the integrated surface, aircraft, and satellite datasets. Through numerous participations, particularly but not limited to the EOS remote-sensing/retrieval and validation projects over the years, NASA/GSFC has developed and continuously refined ground-based networks and mobile observatories that proved to be vital in providing high temporal measurements, which complement and enrich the satellite observations. These are: the AERO NET (AErosol RObotic NETwork) a federation of ground-based globally distributed network of spectral sun-sky photometers; the MPLNET (Micro-Pulse Lidar NETwork, a similarly organized network of micro-pulse lidar systems measuring aerosol and cloud vertical structure continuously; and the SMART-COMMIT (Surface-sensing Measurements for Atmospheric Radiative Transfer - Chemical, Optical & Microphysical Measurements of In-situ Troposphere, mobile observatories, a suite of spectral radiometers and in-situ probes acquiring supersite measurements. Most MPLNET sites are collocated with those of AERONET, and both networks always support the deployment of SMART-COMMIT worldwide. These data products follow the data structure of EOS conventions: Level-0, instrument archived raw data; Level-1 (or 1.5), real-time data with no (or limited) quality assurance; Level-2, not real high temporal and spectral resolutions. In this talk, we will present NASA/GSFC groundbased facilities, serving

  18. Conveying Clinical Reasoning Based on Visual Observation via Eye-Movement Modelling Examples

    Science.gov (United States)

    Jarodzka, Halszka; Balslev, Thomas; Holmqvist, Kenneth; Nystrom, Marcus; Scheiter, Katharina; Gerjets, Peter; Eika, Berit

    2012-01-01

    Complex perceptual tasks, like clinical reasoning based on visual observations of patients, require not only conceptual knowledge about diagnostic classes but also the skills to visually search for symptoms and interpret these observations. However, medical education so far has focused very little on how visual observation skills can be…

  19. Observer and data-driven model based fault detection in Power Plant Coal Mills

    DEFF Research Database (Denmark)

    Fogh Odgaard, Peter; Lin, Bao; Jørgensen, Sten Bay

    2008-01-01

    This paper presents and compares model-based and data-driven fault detection approaches for coal mill systems. The first approach detects faults with an optimal unknown input observer developed from a simplified energy balance model. Due to the time-consuming effort in developing a first principles...... model with motor power as the controlled variable, data-driven methods for fault detection are also investigated. Regression models that represent normal operating conditions (NOCs) are developed with both static and dynamic principal component analysis and partial least squares methods. The residual...... between process measurement and the NOC model prediction is used for fault detection. A hybrid approach, where a data-driven model is employed to derive an optimal unknown input observer, is also implemented. The three methods are evaluated with case studies on coal mill data, which includes a fault...

  20. Estimation of the neuronal activation using fMRI data: An observer-based approach

    KAUST Repository

    Laleg-Kirati, Taous-Meriem

    2013-06-01

    This paper deals with the estimation of the neuronal activation and some unmeasured physiological information using the Blood Oxygenation Level Dependent (BOLD) signal measured using functional Magnetic Resonance Imaging (fMRI). We propose to use an observer-based approach applied to the balloon hemodynamic model. The latter describes the relation between the neural activity and the BOLD signal. The balloon model can be expressed in a nonlinear state-space representation where the states, the parameters and the input (neuronal activation), are unknown. This study focuses only on the estimation of the hidden states and the neuronal activation. The model is first linearized around the equilibrium and an observer is applied to this linearized version. Numerical results performed on synthetic data are presented.

  1. Sensitivity of aerosol retrieval to geometrical configuration of ground-based sun/sky-radiometer observations

    Directory of Open Access Journals (Sweden)

    B. Torres

    2013-03-01

    Full Text Available A sensitivity study of the aerosol optical properties retrieval to the geometrical configuration of the ground-based sky radiometer observations is carried out through the inversion tests. Specifically, the study is focused on the principal plane and almucantar observation, since these geometries are employed in Aeronet (AErosol RObotic NETwork. The following effects has been analyzed with simulated data for both geometries: sensitivity of the retrieval to variability of the observed scattering angle range, uncertainties in the assumptions of the aerosol vertical distribution and surface reflectance, possible instrument pointing errors and the effects of the finite field of view. The synthetic observations of radiometer in the tests were calculated using a previous climatology data of retrieved aerosol over three Aeronet sites: Mongu (Zambia for biomass burning aerosol, Goddard Space Flight Center (Maryland-USA for urban aerosol and Solar Village (Saudi Arabia for desert dust aerosol. The results show that almucantar retrievals, in general, are more reliable than principal plane retrievals in presence of the analyzed error sources. This fact partially can be explained by to practical advantages of almucantar geometry: the symmetry between its left and right branches that helps to eliminate some observational uncertainties and the constant value of optical mass constant during the measurements that makes almucantar observations nearly independent on vertical variability of aerosol. Nevertheless, almucantar retrievals present instabilities at high sun observations due to the reduction of the scattering angle range coverage resulting in decrease of information content. The last part of the study is devoted to identification of possible differences between the aerosol retrieval results obtained from real Aeronet data using both geometries. In particular, we have compared Aeronet retrievals at three different key sites: Mongu (biomass burning

  2. PolarBase: A Database of High-Resolution Spectropolarimetric Stellar Observations

    Science.gov (United States)

    Petit, P.; Louge, T.; Théado, S.; Paletou, F.; Manset, N.; Morin, J.; Marsden, S. C.; Jeffers, S. V.

    2014-05-01

    PolarBase is an evolving database that contains all stellar data collected with the ESPaDOnS and NARVAL high-resolution spectropolarimeters, in their reduced form, as soon as they become public. As of early 2014, observations of 2000 stellar objects throughout the Hertzsprung-Russell diagram are available. Intensity spectra are available for all targets, and the majority of the observations also include simultaneous spectra in circular or linear polarization, with the majority of the polarimetric measurements being performed only in circularly polarized light (Stokes V). Observations are associated with a cross-correlation pseudoline profile in all available Stokes parameters, greatly increasing the detectability of weak polarized signatures. Stokes V signatures are detected for more than 300 stars of all masses and evolutionary stages, and linear polarization is detected in 35 targets. The detection rate in Stokes V is found to be anticorrelated with the stellar effective temperature. This unique set of Zeeman detections offers the first opportunity to run homogeneous magnetometry studies throughout the H-R diagram. The Web interface of PolarBase is available at http://polarbase.irap.omp.eu.

  3. First ground-based FTIR observations of methane in the inner tropics over several years

    OpenAIRE

    Petersen, A. K.; Warneke, T.; Frankenberg, C.; Bergamaschi, P.; Gerbig, C.; Notholt, J.; Buchwitz, M.; Schneising, O.; Schrems, O.

    2010-01-01

    Total column concentrations of methane have been retrieved from ground-based solar absorption FTIR spectra in the near-infrared recorded in Paramaribo (Suriname). The methane FTIR observations are compared with TM5 model simulations and satellite observations from SCIAMACHY, and represent the first validation of SCIAMACHY retrievals in the inner tropics using ground-based remote sensing techniques. Apart from local biomass burning features, our methane FTIR observations agree well with TM5 mo...

  4. Unintentional child neglect: literature review and observational study.

    Science.gov (United States)

    Friedman, Emily; Billick, Stephen B

    2015-06-01

    Child abuse is a problem that affects over six million children in the United States each year. Child neglect accounts for 78% of those cases. Despite this, the issue of child neglect is still not well understood, partially because child neglect does not have a consistent, universally accepted definition. Some researchers consider child neglect and child abuse to be one in the same, while other researchers consider them to be conceptually different. Factors that make child neglect difficult to define include: (1) Cultural differences; motives must be taken into account because parents may believe they are acting in the child's best interests based on cultural beliefs (2) the fact that the effect of child abuse is not always immediately visible; the effects of emotional neglect specifically may not be apparent until later in the child's development, and (3) the large spectrum of actions that fall under the category of child abuse. Some of the risk factors for increased child neglect and maltreatment have been identified. These risk factors include socioeconomic status, education level, family composition, and the presence of dysfunction family characteristics. Studies have found that children from poorer families and children of less educated parents are more likely to sustain fatal unintentional injuries than children of wealthier, better educated parents. Studies have also found that children living with adults unrelated to them are at increased risk for unintentional injuries and maltreatment. Dysfunctional family characteristics may even be more indicative of child neglect. Parental alcohol or drug abuse, parental personal history of neglect, and parental stress greatly increase the odds of neglect. Parental depression doubles the odds of child neglect. However, more research needs to be done to better understand these risk factors and to identify others. Having a clearer understanding of the risk factors could lead to prevention and treatment, as it would allow

  5. Short-arc measurement and fitting based on the bidirectional prediction of observed data

    Science.gov (United States)

    Fei, Zhigen; Xu, Xiaojie; Georgiadis, Anthimos

    2016-02-01

    To measure a short arc is a notoriously difficult problem. In this study, the bidirectional prediction method based on the Radial Basis Function Neural Network (RBFNN) to the observed data distributed along a short arc is proposed to increase the corresponding arc length, and thus improve its fitting accuracy. Firstly, the rationality of regarding observed data as a time series is discussed in accordance with the definition of a time series. Secondly, the RBFNN is constructed to predict the observed data where the interpolation method is used for enlarging the size of training examples in order to improve the learning accuracy of the RBFNN’s parameters. Finally, in the numerical simulation section, we focus on simulating how the size of the training sample and noise level influence the learning error and prediction error of the built RBFNN. Typically, the observed data coming from a 5{}^\\circ short arc are used to evaluate the performance of the Hyper method known as the ‘unbiased fitting method of circle’ with a different noise level before and after prediction. A number of simulation experiments reveal that the fitting stability and accuracy of the Hyper method after prediction are far superior to the ones before prediction.

  6. ROBUST POSITIONING OF LASER BEAMS USING PROPORTIONAL INTEGRAL DERIVATIVE AND BASED OBSERVER-FEEDBACK CONTROL

    Directory of Open Access Journals (Sweden)

    Kwabena A. Konadu

    2013-01-01

    Full Text Available High-precision positioning of laser beams has been a great challenge in industry due to inevitable existence of noise and disturbance. The work presented in this study addresses this problem by employing two different control strategies: Proportional Integral Derivative (PID control and state feedback control with an observer. The control strategies are intended to stabilize the position of a laser beam on a Position Sensing Device (PSD located on a Laser Beam Stabilization (or, laser beam system system. The laser beam system consists of a laser source, a Fast Steering Mirror (FSM, a PSD and a vibrating platform to generate active disturbance. The traditional PID controller is widely used in industry due to its satisfactory performance, various available tuning methods and relatively straightforward design processes. However, design of filters to obtain the derivative signal is challenging and can unexpectedly distort the dynamics of the system being controlled. As an alternative, use of an Observer-Based State Feedback (OBSF method is proposed and implemented. The state-space model of the laser beam system is utilized and an observer is applied to estimate the state of the system, since all the state variables cannot be measured directly. For observer design, eigenvalue assignment and optimal design methods are used and compared in terms of system performance. Also a comparative analysis between the PID and OBSF controllers is provided. Simulations and experimental results show that the OBSF controller rejects disturbance better and has a simpler design procedure.

  7. The Performance and Feasibility of Ensemble Forecast Sensitivity to Observations-based Proactive Quality Control Scheme

    Science.gov (United States)

    Chen, T. C.; Hotta, D.; Kalnay, E.

    2015-12-01

    Operational numerical weather prediction (NWP) systems occasionally exhibit "forecast skill dropouts" in which the forecast skill drops to an abnormally low level, due in part to the assimilation of flawed observational data. Recent studies have shown that a diagnostic technique called Ensemble Forecast Sensitivity to Observations (EFSO) can detect such observations (Kalnay et.al 2012; Ota et al. 2013, Tellus A). Based on this technique, a new Quality Control (QC) scheme called Proactive QC (PQC) has been proposed which detects "flawed" observations using EFSO after just 6 hours forecast, when the analysis at the next cycle becomes available for verification and then repeats the analysis and forecast without using the detected observations (Hotta 2014). In Hotta (2014), it was shown using the JCSDA S4 Testbed that the 6hr PQC reduces the 24-hour forecast errors from the detected skill dropout events. With such encouraging results we are performing preliminary experiments towards operational implementation. First, we show that offline PQC correction can significantly reduce forecast errors up to 5 days, and that the reduction and improved areal coverage can grow with synoptic weather disturbances for several days. Second, with online PQC cycle experiment the reduction of forecast error is shown to be even larger than in the offline version, since the effect could accumulate over each time we perform a PQC correction. Finally, the operational center imposes very tight schedule in order to deliver the products on time, thus the computational cost has to be minimized in order for PQC to be implemented. To avoid performing the analysis twice, which is the most expensive part of PQC, we test the accuracy of constant-K approximation, which assumes the Kalman gain K doesn't change much given the fact that only a small subset of observation is rejected. In this presentation, we will demonstrate the performance and feasibility of PQC implementation in real-time operational

  8. A suggestion for quality assessment in systematic reviews of observational studies in nutritional epidemiology

    Science.gov (United States)

    2016-01-01

    OBJECTIVES: It is important to control the quality level of the observational studies in conducting meta-analyses. The Newcastle-Ottawa Scale (NOS) is a representative tool used for this purpose. We investigated the relationship between high-quality (HQ) defined using NOS and the results of subgroup analysis according to study design. METHODS: We selected systematic review studies with meta-analysis which performed a quality evaluation on observational studies of diet and cancer by NOS. HQ determinations and the distribution of study designs were examined. Subgroup analyses according to quality level as defined by the NOS were also extracted. Equivalence was evaluated based on the summary effect size (sES) and 95% confidence intervals computed in the subgroup analysis. RESULTS: The meta-analysis results of the HQ and cohort groups were identical. The overall sES, which was obtained by combining the sES when equivalence was observed between the cohort and case-control groups, also showed equivalence. CONCLUSIONS: The results of this study suggest that it is more reasonable to control for quality level by performing subgroup analysis according to study design rather than by using HQ based on the NOS quality assessment tool. PMID:27156344

  9. Optimal Observability Analysis of Gimbled Inertial Navigation System on the Moving Base

    Institute of Scientific and Technical Information of China (English)

    于家城; 陈家斌

    2004-01-01

    To investigate the observability of gimbled inertial navigation system when the base moves on the basis of piece-wise constant system's observability theory and singular value decomposition, the variation of the singular value in the observability matrix with time is discussed. The simulation results reveal that only if orientation angle is 60° and the flight route is S-figure in initial alignment, the optimal observability is obtained, thus a theoretical foundation for fast and accurate alignment of GINS is provided.

  10. Spatial distribution of polychlorinated naphthalenes in the atmosphere across North China based on gridded field observations

    International Nuclear Information System (INIS)

    Polychlorinated naphthalenes (PCNs) belong to a group of dioxin-like pollutants; however little information is available on PCNs in North China. In this study, gridded field observations by passive air sampling at 90 sites were undertaken to determine the levels, spatial distributions, and sources of PCNs in the atmosphere of North China. A median concentration of 48 pg m−3 (range: 10–2460 pg m−3) for ∑29PCNs indicated heavy PCN pollution. The compositional profile indicated that nearly 90% of PCNs observed were from thermal processes rather than from commercial mixtures. Regarding the source type, a quantitative apportionment suggested that local non-point emissions contributed two-thirds of the total PCNs observed in the study, whereas a point source of electronic-waste recycling site contributed a quarter of total PCNs. The estimated toxic equivalent quantity for dioxin-like PCNs ranged from 0.97 to 687 fg TEQ m−3, with the electronic-waste recycling site with the highest risk. -- Highlights: •Gridded atmospheric concentrations of PCNs were measured across North China. •Relatively high levels of PCNs were observed in the atmosphere of North China. •Thermal processes were the major source of PCNs based on the compositional profile. •Source apportionment was performed between point and non-point sources. •Significant dioxin-like toxicity of PCNs was found particularly at an e-waste site. -- High levels of PCNs were observed in the atmosphere of North China, which were mainly from thermal processes

  11. Study of single and combined mass-sensitive observables of cosmic ray induced extensive air showers

    Science.gov (United States)

    Rastegarzadeh, G.; Nemati, M.

    2016-03-01

    In this study, combinations of the global arrival time, (Δτ_{global}), pseudorapidity, and lateral density distribution (ρ_{μ}) of muons, which are three mass-sensitive observables of cosmic ray induced extensive air showers, have been used as new parameters to study the primary mass discrimination around the knee energies (100 TeV-10 PeV). This is a simulation-based study and the simulations have been performed for the KASCADE array at Karlsruhe and the Alborz-I array at Tehran to study the effect of the altitude on the quality of the primary mass discrimination. The merit factors of the single and combined three mass-sensitive observables have been calculated to compare the discrimination power of combined and single observables. We have used the CORSIKA 7.4 code to simulate the extensive air showers (EASs) sample sets. Considering all aspects of our study, it is found that the ratio of the global time to the lateral density distribution of the muons gives better results than other ratios; also in the case of single observables, the muon density gives better results compared with the other observables. Also it is shown that below 1 PeV primary energies, the ratio of the muon global time to the muon density (Δτ_{global}/ρ_{μ}) results in a better mass discrimination relative to the muon density only.

  12. Observability analysis for model-based fault detection and sensor selection in induction motors

    International Nuclear Information System (INIS)

    Sensors in different types and configurations provide information on the dynamics of a system. For a specific task, the question is whether measurements have enough information or whether the sensor configuration can be changed to improve the performance or to reduce costs. Observability analysis may answer the questions. This paper presents a general algorithm of nonlinear observability analysis with application to model-based diagnostics and sensor selection in three-phase induction motors. A bond graph model of the motor is developed and verified with experiments. A nonlinear observability matrix based on Lie derivatives is obtained from state equations. An observability index based on the singular value decomposition of the observability matrix is obtained. Singular values and singular vectors are used to identify the most and least observable configurations of sensors and parameters. A complex step derivative technique is used in the calculation of Jacobians to improve the computational performance of the observability analysis. The proposed algorithm of observability analysis can be applied to any nonlinear system to select the best configuration of sensors for applications of model-based diagnostics, observer-based controller, or to determine the level of sensor redundancy. Observability analysis on induction motors provides various sensor configurations with corresponding observability indices. Results show the redundancy levels for different sensors, and provide a sensor selection guideline for model-based diagnostics, and for observer-based controllers. The results can also be used for sensor fault detection and to improve the reliability of the system by increasing the redundancy level in measurements

  13. Observability analysis for model-based fault detection and sensor selection in induction motors

    Science.gov (United States)

    Nakhaeinejad, Mohsen; Bryant, Michael D.

    2011-07-01

    Sensors in different types and configurations provide information on the dynamics of a system. For a specific task, the question is whether measurements have enough information or whether the sensor configuration can be changed to improve the performance or to reduce costs. Observability analysis may answer the questions. This paper presents a general algorithm of nonlinear observability analysis with application to model-based diagnostics and sensor selection in three-phase induction motors. A bond graph model of the motor is developed and verified with experiments. A nonlinear observability matrix based on Lie derivatives is obtained from state equations. An observability index based on the singular value decomposition of the observability matrix is obtained. Singular values and singular vectors are used to identify the most and least observable configurations of sensors and parameters. A complex step derivative technique is used in the calculation of Jacobians to improve the computational performance of the observability analysis. The proposed algorithm of observability analysis can be applied to any nonlinear system to select the best configuration of sensors for applications of model-based diagnostics, observer-based controller, or to determine the level of sensor redundancy. Observability analysis on induction motors provides various sensor configurations with corresponding observability indices. Results show the redundancy levels for different sensors, and provide a sensor selection guideline for model-based diagnostics, and for observer-based controllers. The results can also be used for sensor fault detection and to improve the reliability of the system by increasing the redundancy level in measurements.

  14. A study on diffuse source detection by HXMT scanning observation

    CERN Document Server

    Guan, Ju; Wu, Mei; Song, Li-Ming; Huo, Zhuo-Xi

    2015-01-01

    The Hard X-ray Modulation Telescope (HXMT) is a collimated scan X-ray satellite mainly devoted to a sensitive all-sky survey and pointed observations in 1-250 keV. We expect various diffuse sources to be detected in its scanning observations due to the large rigidity factor of the telescope. Diffuse source detection performance of HXMT scanning observation depends not only on the instrument but also on its data analysis method since images have to be reconstructed from HXMT observed data. In this paper, we introduce a multiscale maximum entropy (MSME) algorithm for HXMT image restoration and propose an improved method, ensemble multiscale maximum entropy (EMSME) method, to alleviate the problem of mode mixing exiting in MSME. Simulation have been performed on the detection of the diffuse source Cen A by HXMT in the all-sky survey mode. The results show that the MSME method is adapted to the deconvolution task of HXMT for diffuse source detection and the improved method could suppress noise and improve the cor...

  15. Creation of an ensemble of simulated cardiac cases and a human observer study: tools for the development of numerical observers for SPECT myocardial perfusion imaging

    Science.gov (United States)

    O'Connor, J. Michael; Pretorius, P. Hendrik; Gifford, Howard C.; Licho, Robert; Joffe, Samuel; McGuiness, Matthew; Mehurg, Shannon; Zacharias, Michael; Brankov, Jovan G.

    2012-02-01

    Our previous Single Photon Emission Computed Tomography (SPECT) myocardial perfusion imaging (MPI) research explored the utility of numerical observers. We recently created two hundred and eighty simulated SPECT cardiac cases using Dynamic MCAT (DMCAT) and SIMIND Monte Carlo tools. All simulated cases were then processed with two reconstruction methods: iterative ordered subset expectation maximization (OSEM) and filtered back-projection (FBP). Observer study sets were assembled for both OSEM and FBP methods. Five physicians performed an observer study on one hundred and seventy-nine images from the simulated cases. The observer task was to indicate detection of any myocardial perfusion defect using the American Society of Nuclear Cardiology (ASNC) 17-segment cardiac model and the ASNC five-scale rating guidelines. Human observer Receiver Operating Characteristic (ROC) studies established the guidelines for the subsequent evaluation of numerical model observer (NO) performance. Several NOs were formulated and their performance was compared with the human observer performance. One type of NO was based on evaluation of a cardiac polar map that had been pre-processed using a gradient-magnitude watershed segmentation algorithm. The second type of NO was also based on analysis of a cardiac polar map but with use of a priori calculated average image derived from an ensemble of normal cases.

  16. Ground-based Observations of the Solar Sources of Space Weather

    Science.gov (United States)

    Veronig, A. M.; Pötzi, W.

    2016-04-01

    Monitoring of the Sun and its activity is a task of growing importance in the frame of space weather research and awareness. Major space weather disturbances at Earth have their origin in energetic outbursts from the Sun: solar flares, coronal mass ejections and associated solar energetic particles. In this review we discuss the importance and complementarity of ground-based and space-based observations for space weather studies. The main focus is drawn on ground-based observations in the visible range of the spectrum, in particular in the diagnostically manifold Hα spectral line, which enables us to detect and study solar flares, filaments (prominences), filament (prominence) eruptions, and Moreton waves. Existing Hα networks such as the GONG and the Global High-Resolution Hα Network are discussed. As an example of solar observations from space weather research to operations, we present the system of real-time detection of Hα flares and filaments established at Kanzelhöhe Observatory (KSO; Austria) in the frame of the space weather segment of the ESA Space Situational Awareness programme (swe.ssa.esa.int). An evaluation of the system, which is continuously running since July 2013 is provided, covering an evaluation period of almost 2.5 years. During this period, KSO provided 3020 hours of real-time Hα observations at the ESA SWE portal. In total, 824 Hα flares were detected and classified by the real-time detection system, including 174 events of Hα importance class 1 and larger. For the total sample of events, 95 % of the automatically determined flare peak times lie within ±5 min of the values given in the official optical flares reports (by NOAA and KSO), and 76 % of the start times. The heliographic positions determined are better than ±5°. The probability of detection of flares of importance 1 or larger is 95 %, with a false alarm rate of 16 %. These numbers confirm the high potential of automatic flare detection and alerting from ground-based

  17. An Evaluation of Lightning Flash Rate Parameterizations Based on Observations of Colorado Storms during DC3

    Science.gov (United States)

    Basarab, B.; Fuchs, B.; Rutledge, S. A.

    2013-12-01

    Predicting lightning activity in thunderstorms is important in order to accurately quantify the production of nitrogen oxides (NOx = NO + NO2) by lightning (LNOx). Lightning is an important global source of NOx, and since NOx is a chemical precursor to ozone, the climatological impacts of LNOx could be significant. Many cloud-resolving models rely on parameterizations to predict lightning and LNOx since the processes leading to charge separation and lightning discharge are not yet fully understood. This study evaluates predicted flash rates based on existing lightning parameterizations against flash rates observed for Colorado storms during the Deep Convective Clouds and Chemistry Experiment (DC3). Evaluating lightning parameterizations against storm observations is a useful way to possibly improve the prediction of flash rates and LNOx in models. Additionally, since convective storms that form in the eastern plains of Colorado can be different thermodynamically and electrically from storms in other regions, it is useful to test existing parameterizations against observations from these storms. We present an analysis of the dynamics, microphysics, and lightning characteristics of two case studies, severe storms that developed on 6 and 7 June 2012. This analysis includes dual-Doppler derived horizontal and vertical velocities, a hydrometeor identification based on polarimetric radar variables using the CSU-CHILL radar, and insight into the charge structure using observations from the northern Colorado Lightning Mapping Array (LMA). Flash rates were inferred from the LMA data using a flash counting algorithm. We have calculated various microphysical and dynamical parameters for these storms that have been used in empirical flash rate parameterizations. In particular, maximum vertical velocity has been used to predict flash rates in some cloud-resolving chemistry simulations. We diagnose flash rates for the 6 and 7 June storms using this parameterization and compare

  18. Theory and experiment of observer based magnetostrictive self-sensing actuator

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Giant magnetostrictive actuators (GMAs) often work in a close-loop feedback system. This system needs independent sensors which may be difficult to be fixed, besides, excessive sensors may cause more unpredicted problems in a large system.This paper aims to develop a self-sensing GMA. An observer based on piezomagnetic equations is constructed to estimate the stress and strain of the magnetostrictive material. The observer based self-sensing approach depends on the facts that the magnetic field is controllable and that the magnetic induction is measurable. Aiming at the nonlinear hysteresis in magnetization, a hysteresis compensation observer based on Preisach model is developed. Experiment verified the availability of the observer approach,and the hysteresis compensation observer has higher tracking precision than linear observer for dynamic force sensing.

  19. The transient observation-based particle (TOP model and its potential application in radiation effects evaluation

    Directory of Open Access Journals (Sweden)

    Mazzino Laura

    2013-01-01

    Full Text Available The evaluation of the radiation hazards on components used in space environment is based on the knowledge of the radiation level encountered on orbit. The models that are widely used to assess the near-Earth environment for a given mission are empirical trapped radiation models derived from a compilation of spacecraft measurements. However, these models are static and hence are not suited for describing the short timescale variations of geomagnetic conditions. The transient observation-based particle (TOP-model tends to break with this classical approach by introducing dynamic features based on the observation and characterization of transient particle flux events in addition to classical mapping of steady-state flux levels. In order to get a preliminary version of an operational model (actually only available for electrons at low Earth orbit, LEO, (i the steady-state flux level, (ii the flux enhancements probability distribution functions, and (iii the flux decay-time constants (at given energy and positions in space were determined, and an original dynamic model skeleton with these input parameters has been developed. The methodology is fully described and first flux predictions from the model are presented. In order to evaluate the net effects of radiation on a component, it is important to have an efficient tool that calculates the transfer of the outer radiation environment through the spacecraft material, toward the location of the component under investigation. Using the TOP-model space radiation fluxes and the transmitted radiation environment characteristics derived through GEANT4 calculations, a case study for electron flux/dose variations in a small silicon volume is performed. Potential cases are assessed where the dynamic of the spacecraft radiation environment may have an impact on the observed radiation effects.

  20. Smoking Behaviors Among Cancer Survivors: An Observational Clinical Study

    OpenAIRE

    Burke, Lola; Miller, Lesley-Ann; Saad, Ayman; Abraham, Jame

    2009-01-01

    Studies have shown that smoking can adversely affect the outcomes of different modalities of cancer treatment. This study looks at smoking behaviors among cancer survivors to collect necessary information to create successful smoking cessation interventions.

  1. Observations of surface radiation and stratospheric processes at Thule Air Base, Greenland, during the IPY

    Directory of Open Access Journals (Sweden)

    Giovanni Muscari

    2014-06-01

    Full Text Available Ground-based measurements of atmospheric parameters have been carried out for more than 20 years at the Network for the Detection of Atmospheric Composition Change (NDACC station at Thule Air Base (76.5°N, 68.8°W, on the north-western coast of Greenland. Various instruments dedicated to the study of the lower and middle polar atmosphere are installed at Thule in the framework of a long standing collaboration among Danish, Italian, and US research institutes and universities. This effort aims at monitoring the composition, structure and dynamics of the polar stratosphere, and at studying the Arctic energy budget and the role played by different factors, such as aerosols, water vapour, and surface albedo. During the International Polar Year (IPY, in winter 2008-2009, an intensive measurement campaign was conducted at Thule within the framework of the IPY project “Ozone layer and UV radiation in a changing climate evaluated during IPY” (ORACLE-O3 which sought to improve our understanding of the complex mechanisms that lead to the Arctic stratospheric O3 depletion. The campaign involved a lidar system, measuring aerosol backscatter and depolarization ratios up to 35 km and atmospheric temperature profiles from 25 to 70 km altitude, a ground-based millimeter-wave spectrometer (GBMS used to derive stratospheric mixing ratio profiles of different chemical species involved in the stratospheric ozone depletion cycle, and then ground-based radiometers and a Cimel sunphotometer to study the Arctic radiative budget at the surface. The observations show that the surface radiation budget is mainly regulated by the longwave component throughout most of the year. Clouds have a significant impact contributing to enhance the role of longwave radiation. Besides clouds, water vapour seasonal changes produce the largest modification in the shortwave component at the surface, followed by changes in surface albedo and in aerosol amounts. For what concerns the

  2. Parallel-cascade-based mechanisms for heating solar coronal loops: test against observations

    CERN Document Server

    Li, Bo; Li, Xing; Xia, Li-Dong

    2014-01-01

    The heating of solar coronal loops is at the center of the problem of coronal heating. Given that the origin of the fast solar wind has been tracked down to atmospheric layers with transition region or even chromospheric temperatures, it is worthy attempting to address whether the mechanisms proposed to provide the basal heating of the solar wind apply to coronal loops as well. We extend the loop studies based on a classical parallel-cascade scenario originally proposed in the solar wind context by considering the effects of loop expansion, and perform a parametric study to directly contrast the computed loop densities and electron temperatures with those measured by TRACE and YOHKOH/SXT. This comparison yields that with the wave amplitudes observationally constrained by SUMER measurements, while the computed loops may account for a significant fraction of SXT loops, they seem too hot when compared with TRACE loops. Lowering the wave amplitudes does not solve this discrepancy, introducing magnetic twist will ...

  3. Assessment of satellite-based aerosol optical depth using continuous lidar observation

    Science.gov (United States)

    Lin, C. Q.; Li, C. C.; Lau, A. K. H.; Yuan, Z. B.; Lu, X. C.; Tse, K. T.; Fung, J. C. H.; Li, Y.; Yao, T.; Su, L.; Li, Z. Y.; Zhang, Y. Q.

    2016-09-01

    Due to a reliance on solar radiation, the aerosol optical depth (AOD) is observed only during the day by passive satellite-based instruments such as the MODerate resolution Imaging Spectroradiometer (MODIS). Research on urban air quality, atmospheric turbidity, and evolution of aerosols in the atmospheric boundary layer, however, requires 24-h measurement of aerosols. A lidar system is capable of detecting the vertical distribution of the aerosol extinction coefficient and calculating the AOD throughout the day, but routinely lidar observation is still quite limited and the results from MODIS and lidar sometimes are contradictory in China. In this study, long-term lidar observations from 2005 to 2009 over Hong Kong were analyzed with a focus on identification of the reasons for different seasonal variation in the AOD data obtained from MODIS and lidar. The lidar-retrieved AOD shows the lowest average level, but has the most significant diurnal variation during the summer. When considering only a 5-h period between 10:00 a.m. and 3:00 p.m. local time to match satellite passages, the average of the lidar-retrieved AOD doubles during the summer and exceeds that during the winter. This finding is consistent with the MODIS observation of a higher AOD during the summer and a lower AOD during the winter. The increase in the aerosol extinction coefficient in the upper level of the mixing layer makes the greatest contribution to the increase in the AOD at midday during the summer. These assessments suggest that large over-estimation may occur when long-term averages of AOD are estimated from passive satellite observations.

  4. An observational asteroseismic study of the pulsating B-stars in the open cluster NGC 884

    CERN Document Server

    Saesen, S; Aerts, C; Miglio, A; Carrier, F

    2013-01-01

    Recent progress in the seismic interpretation of field {\\beta} Cep stars has resulted in improvements of the physical description in the stellar structure and evolution model computations of massive stars. Further asteroseismic constraints can be obtained from studying ensembles of stars in a young open cluster, which all have similar age, distance and chemical composition. We present an observational asteroseismic study based on the discovery of numerous multi-periodic and mono-periodic B-stars in the open cluster NGC 884. Our study illustrates the current status of ensemble asteroseismology of a young open cluster.

  5. Solar energetic particles: observational studies and magnetohydrodynamic simulation

    International Nuclear Information System (INIS)

    Solar activity manifests itself through highly dynamical events, such as flares and coronal mass ejections, which result in energy release by magnetic reconnection. This thesis focuses on two manifestations of this energy release: solar energetic particles and dynamics of magnetic reconnection. The first part of my work consists in the detailed temporal analysis of several electromagnetic signatures, produced by energetic particles in the solar atmosphere, with respect to the energetic particle flux at Earth. Using multi-instrument observations, I highlighted that particles can be accelerated by the flare to relativistic energies during a specific episode of acceleration in the impulsive phase. This showed that particles traveled a longer path length than the theoretical length generally assumed. Using in-situ measurements of magnetic field and plasma, I identified the interplanetary magnetic field for 10 particle events, and performing a velocity dispersion analysis I obtained the interplanetary length traveled by particles. I showed that the magnetic structure of the interplanetary medium play a crucial role in the association of the particle flux at Earth and the acceleration signatures of particles at the Sun. The second part of my work focuses on the dynamics of magnetic reconnection. Observationally, the best evidence for magnetic reconnection is the appearance of brightnesses at the solar surface. Performing the first data-driven 3 dimensional magneto-hydrodynamic (MHD) simulation of an observed event, I discovered that the evolution of brightnesses can be explained by the succession of two different reconnection regimes, induced by a new topological association where null-point separatrix lines are embedded in quasi-separatrix layers. This new topological association induces a change of field line connectivity, but also a continuous reconnection process, leading to an apparent slipping motion of reconnected field lines. From a MHD simulation I showed that

  6. Temporal sequence in observational studies to establish causality

    Directory of Open Access Journals (Sweden)

    Luis Carlos Silva Ayçaguer, PhD

    2014-05-01

    Full Text Available The article includes a brief summary on the scope of the notions of causality and risk and considers some operational difficulties that arise when dealing with problems associated with them. It underscores the vital importance of timing and its link with the most commonly used observational research designs that address causal relationships. The article describes in detail the need to record the order in which the relevant events occur and how to consider this in the analysis. A detailed example of errors that are usually incurred in and their effect is provided.

  7. Astronomical Observations Astronomy and the Study of Deep Space

    CERN Document Server

    2010-01-01

    Our Search for knowledge about the universe has been remarkable, heartbreaking, fantastical, and inspiring, and this search is just beginning. Astronomical Observations is part of a 7 book series that takes readers through a virtual time warp of our discovery. From the nascent space programs of the 1960's to today's space tourism and the promise of distant planet colonization, readers will be transfixed. Throughout this journey of the mind, Earth-bound explorers gain keen insight into the celestial phenomena that have fascinated humans for centuries. Thrilling narratives about indefatigable sc

  8. Study of the NWC electrons belt observed on DEMETER Satellite

    OpenAIRE

    Li, Xinqiao; Ma, Yuqian; Ping WANG; Wang, Huanyu; Lu, Hong; Zhang, Xuemin; Huang, Jianping; Shi, Feng; Yu, Xiaoxia; Xu, Yanbing; Meng, Xiangcheng; Wang, Hui; Zhao, Xiaoyun; M. Parrot

    2010-01-01

    We analyzed observation data collected by the Instrument for the Detection of Particles (IDP) on board of DEMETER satellite during the period of total seventeen months in 2007 and 2008. In the meantime, the VLF transmitter located at NWC ground station was shutdown for seven months and working for total ten months. Our analysis, for the first time, revealed in details the transient properties of the space electrons induced by the man-made VLF wave emitted by the transmitter at NWC. First, we ...

  9. Multistakeholder as Governance Groups: Observations from Case Studies

    OpenAIRE

    Gasser, Urs; Budish, Ryan Hal; Meyers West, Sarah

    2015-01-01

    This paper synthesizes a set of twelve case studies of real-world governance structures. Together with the underlying case studies, it is the result of a globally coordinated, independent academic research pilot project by the Global Network of Interdisciplinary Internet & Society Research Centers (NoC). Facilitated by the Berkman Center for Internet & Society at Harvard University, this study examines existing multistakeholder governance groups with the goal of informing the evolution of — a...

  10. A Big-Data-based platform of workers' behavior: Observations from the field.

    Science.gov (United States)

    Guo, S Y; Ding, L Y; Luo, H B; Jiang, X Y

    2016-08-01

    Behavior-Based Safety (BBS) has been used in construction to observe, analyze and modify workers' behavior. However, studies have identified that BBS has several limitations, which have hindered its effective implementation. To mitigate the negative impact of BBS, this paper uses a case study approach to develop a Big-Data-based platform to classify, collect and store data about workers' unsafe behavior that is derived from a metro construction project. In developing the platform, three processes were undertaken: (1) a behavioral risk knowledge base was established; (2) images reflecting workers' unsafe behavior were collected from intelligent video surveillance and mobile application; and (3) images with semantic information were stored via a Hadoop Distributed File System (HDFS). The platform was implemented during the construction of the metro-system and it is demonstrated that it can effectively analyze semantic information contained in images, automatically extract workers' unsafe behavior and quickly retrieve on HDFS as well. The research presented in this paper can enable construction organizations with the ability to visualize unsafe acts in real-time and further identify patterns of behavior that can jeopardize safety outcomes. PMID:26614050

  11. Orbit determination based on meteor observations using numerical integration of equations of motion

    Science.gov (United States)

    Dmitriev, Vasily; Lupovka, Valery; Gritsevich, Maria

    2015-11-01

    Recently, there has been a worldwide proliferation of instruments and networks dedicated to observing meteors, including airborne and future space-based monitoring systems . There has been a corresponding rapid rise in high quality data accumulating annually. In this paper, we present a method embodied in the open-source software program "Meteor Toolkit", which can effectively and accurately process these data in an automated mode and discover the pre-impact orbit and possibly the origin or parent body of a meteoroid or asteroid. The required input parameters are the topocentric pre-atmospheric velocity vector and the coordinates of the atmospheric entry point of the meteoroid, i.e. the beginning point of visual path of a meteor, in an Earth centered-Earth fixed coordinate system, the International Terrestrial Reference Frame (ITRF). Our method is based on strict coordinate transformation from the ITRF to an inertial reference frame and on numerical integration of the equations of motion for a perturbed two-body problem. Basic accelerations perturbing a meteoroid's orbit and their influence on the orbital elements are also studied and demonstrated. Our method is then compared with several published studies that utilized variations of a traditional analytical technique, the zenith attraction method, which corrects for the direction of the meteor's trajectory and its apparent velocity due to Earth's gravity. We then demonstrate the proposed technique on new observational data obtained from the Finnish Fireball Network (FFN) as well as on simulated data. In addition, we propose a method of analysis of error propagation, based on general rule of covariance transformation.

  12. An optimal-estimation-based aerosol retrieval algorithm using OMI near-UV observations

    Science.gov (United States)

    Jeong, U.; Kim, J.; Ahn, C.; Torres, O.; Liu, X.; Bhartia, P. K.; Spurr, R. J. D.; Haffner, D.; Chance, K.; Holben, B. N.

    2016-01-01

    An optimal-estimation(OE)-based aerosol retrieval algorithm using the OMI (Ozone Monitoring Instrument) near-ultraviolet observation was developed in this study. The OE-based algorithm has the merit of providing useful estimates of errors simultaneously with the inversion products. Furthermore, instead of using the traditional look-up tables for inversion, it performs online radiative transfer calculations with the VLIDORT (linearized pseudo-spherical vector discrete ordinate radiative transfer code) to eliminate interpolation errors and improve stability. The measurements and inversion products of the Distributed Regional Aerosol Gridded Observation Network campaign in northeast Asia (DRAGON NE-Asia 2012) were used to validate the retrieved aerosol optical thickness (AOT) and single scattering albedo (SSA). The retrieved AOT and SSA at 388 nm have a correlation with the Aerosol Robotic Network (AERONET) products that is comparable to or better than the correlation with the operational product during the campaign. The OE-based estimated error represented the variance of actual biases of AOT at 388 nm between the retrieval and AERONET measurements better than the operational error estimates. The forward model parameter errors were analyzed separately for both AOT and SSA retrievals. The surface reflectance at 388 nm, the imaginary part of the refractive index at 354 nm, and the number fine-mode fraction (FMF) were found to be the most important parameters affecting the retrieval accuracy of AOT, while FMF was the most important parameter for the SSA retrieval. The additional information provided with the retrievals, including the estimated error and degrees of freedom, is expected to be valuable for relevant studies. Detailed advantages of using the OE method were described and discussed in this paper.

  13. Mucocutaneous manifestations of acquired hypoparathyroidism: An observational study

    OpenAIRE

    Somenath Sarkar; Modhuchanda Mondal; Kapildev Das; Arpit Shrimal

    2012-01-01

    Hypoparathyroidism is a disorder of calcium and phosphorus metabolism due to decreased secretion of parathyroid hormone. Hypoparathyroidism can be hereditary and acquired. Acquired hypoparathyroidism usually occurs following neck surgery (thyroid surgery or parathyroid surgery). Along with systemic manifestations, hypoparathyroidism produces some skin manifestations. Lack of study regarding mucocutaneous manifestations of acquired hypoparathyroidism prompted us to undertake this study. To eva...

  14. Spatial Estimation of Sub-Hour Global Horizontal Irradiance Based on Official Observations and Remote Sensors

    Science.gov (United States)

    Gutierrez-Corea, Federico-Vladimir; Manso-Callejo, Miguel-Angel; Moreno-Regidor, María-Pilar; Velasco-Gómez, Jesús

    2014-01-01

    This study was motivated by the need to improve densification of Global Horizontal Irradiance (GHI) observations, increasing the number of surface weather stations that observe it, using sensors with a sub-hour periodicity and examining the methods of spatial GHI estimation (by interpolation) with that periodicity in other locations. The aim of the present research project is to analyze the goodness of 15-minute GHI spatial estimations for five methods in the territory of Spain (three geo-statistical interpolation methods, one deterministic method and the HelioSat2 method, which is based on satellite images). The research concludes that, when the work area has adequate station density, the best method for estimating GHI every 15 min is Regression Kriging interpolation using GHI estimated from satellite images as one of the input variables. On the contrary, when station density is low, the best method is estimating GHI directly from satellite images. A comparison between the GHI observed by volunteer stations and the estimation model applied concludes that 67% of the volunteer stations analyzed present values within the margin of error (average of ±2 standard deviations). PMID:24732102

  15. Spatial Estimation of Sub-Hour Global Horizontal Irradiance Based on Official Observations and Remote Sensors

    Directory of Open Access Journals (Sweden)

    Federico-Vladimir Gutierrez-Corea

    2014-04-01

    Full Text Available This study was motivated by the need to improve densification of Global Horizontal Irradiance (GHI observations, increasing the number of surface weather stations that observe it, using sensors with a sub-hour periodicity and examining the methods of spatial GHI estimation (by interpolation with that periodicity in other locations. The aim of the present research project is to analyze the goodness of 15-minute GHI spatial estimations for five methods in the territory of Spain (three geo-statistical interpolation methods, one deterministic method and the HelioSat2 method, which is based on satellite images. The research concludes that, when the work area has adequate station density, the best method for estimating GHI every 15 min is Regression Kriging interpolation using GHI estimated from satellite images as one of the input variables. On the contrary, when station density is low, the best method is estimating GHI directly from satellite images. A comparison between the GHI observed by volunteer stations and the estimation model applied concludes that 67% of the volunteer stations analyzed present values within the margin of error (average of ±2 standard deviations.

  16. Observational Studies on Evaluating the Safety and Adverse Effects of Traditional Chinese Medicine

    Directory of Open Access Journals (Sweden)

    Jung-Nein Lai

    2013-01-01

    Full Text Available Background. This study aims to share our experiences when carrying out observational studies of traditional Chinese medicine (TCM. Methods. We have proactively monitored the safety profiles of Duhuo Jisheng Tang (DJT, Suan Zao Ren Tang (SZRT, and TMN-1. A list of adverse events (AEs, complete blood counts, and liver and kidney function tests were obtained from the participants during their scheduled hospital visits. Retrospective observational studies were conducted based on the reimbursement database of the National Health Insurance system, Taiwan, to explore the relationship between the use of TCM that have been adulterated by aristolochic acid and the risk from both nephrotoxins and carcinogens. Results. A total of 221, 287, and 203 AEs were detected after SZRT, DJT, and TMN-1 had been taken, respectively. Dizziness, headache, stomach ache, and diarrhea were judged to be probably related to SZRT treatment. Retrospective observational studies found an association between the consumption of aristolochic acid-containing Chinese formulae such as Mu Tong and an increased risk of CKD, ESRD, and urinary tract cancer. Conclusion. Prospective and retrospective observational studies seem to have specific advantages when investigating the safety and adverse effects of TCM therapies, as well as possibly other alternative/complementary therapies.

  17. Observer based temperature control for reduced thermal cycling in power electronic cooling

    International Nuclear Information System (INIS)

    This paper presents an advanced dynamic cooling strategy for multi-layer structured power electronic modules. A observer based feedback controller is proposed to reduce a power device or module's thermal cycle amplitude during operation, with the aim of improving reliability and lifetime. The full-state observer design is based on a developed Cauer type thermal model. The observer enables estimation and control of the temperature at reliability critical locations only measuring one accessible location. This makes the method particularly powerful and suitable for application in power systems. The designed strategy is confirmed experimentally. Although the experiment is developed for a specific application scenario, the proposed strategy is of general validity. - Highlights: •An observer based temperature control strategy is proposed. •This strategy aims at improving power module's reliability and lifetime. •Reduce temperature change under various power dissipations and ambient temperatures. •The observer can estimate temperature without direct sensing

  18. Theoretical and Observational Studies of the Central Engines of AGN

    Science.gov (United States)

    Sivron, Ran

    1995-01-01

    In Active Galactic Nuclei (AGN) the luminosity is so intense that the effect of radiation pressure on a particle may exceed the gravitational attraction. It was shown that when such luminosities are reached, relatively cold (not completely ionized) thermal matter clouds may form in the central engines of AGN, where most of the luminosity originates. We show that the spectrum of emission from cold clouds embedded in hot relativistic matter is similar to the observed spectrum. We also show that within the hot relativistic matter, cold matter moves faster than the speed of sound or the Alfven speed, and shocks form. The shocks provide a mechanism by which a localized perturbation can propagate throughout the central engine. The shocked matter can emit the observed luminosity, and can explain the flux and spectral variability. It may also provide an efficient mechanism for the outward transfer of angular momentum and provide the outward flow of winds. With observations from X-ray satellites, emission features from the cold and hot matter may be revealed. Our analysis of X-ray data from the Seyfert 1 galaxy MCG - 6-30-15 over five years using detectors on the Ginga and Rosat satellites, revealed some interesting variable features. A source with hot matter emits non-thermal radiation which is Compton reflected from cold matter and then absorbed by warm (partially ionized) absorbing matter in the first model, which can be fit to the data if both the cold and warm absorbers are near the central engine. An alternative model in which the emission from the hot matter is partially covered by very warm matter (in which all elements except Iron are mostly ionized) is also successful. In this model the cold and warm matter may be at distances of up to 100 times the size of the central engine, well within the region where broad optical lines are produced. The flux variability is more naturally explained by the second model. Our results support the existence of cold matter in, or

  19. Study on autonomous satellite navigation from SHAR observations

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This paper uses two navigation schemes to prove the potential of a novel autonomous orbit determination with stellar horizon atmospheric refraction measurements. Scheme one needs a single processor and uses an extended Kalman filter. The second scheme needs two parallel processors. One processor uses a batched leastsquare initial state estimator and a high-precision dynamic state propagator. The other processor uses a real-time orbit predictor. Simulations have been executed respectively for three types (low/medial/high) of satellite orbits on which various numbers of stars. Are observed. The results show both schemes can autonomously determine the orbits with a considerable performance. The second Scheme in general performs a little better than the first scheme.

  20. A submllimeter observation and study of star-forming regions

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Using the 3-m radio telescope of KOSMA, we mapped 12CO (J = 3-2) lines for three molecular clouds, B35, S146 and TMC-2A. High-velocity molecular outflows are found in all these regions. The physical and dynamical parameters of the outflows are derived, and their shapes and driving sources are analyzed. Contour maps of center velocities show that the large scale systematic gradients exist in the three clouds. These observed motions are best explained by rotation after excluding the cause of outflows. Furthermore, in the core region of TMC-2A there is a velocity gradient in opposite direction from that of the large scale. It may be caused by magnetic braking. Finally, angular velocities of the clouds are calculated, and the effects of rotation against gravity and lowering the star-formation rate are also analyzed.

  1. GNSS-based Observations and Simulations of Spectral Scintillation Indices in the Arctic Ionosphere

    DEFF Research Database (Denmark)

    Durgonics, Tibor; Hoeg, Per; von Benzon, Hans-Henrik;

    During disturbed times, ionospheric scintillations can be severe and adversely impact satellite-based positioning and radio transmissions. The scintillation occurs in the amplitude, phase, polarization, and angle of arrival of the signal. Precise observation, classification, modeling, forecasting...

  2. Neural-network-observer-based optimal control for unknown nonlinear systems using adaptive dynamic programming

    Science.gov (United States)

    Liu, Derong; Huang, Yuzhu; Wang, Ding; Wei, Qinglai

    2013-09-01

    In this paper, an observer-based optimal control scheme is developed for unknown nonlinear systems using adaptive dynamic programming (ADP) algorithm. First, a neural-network (NN) observer is designed to estimate system states. Then, based on the observed states, a neuro-controller is constructed via ADP method to obtain the optimal control. In this design, two NN structures are used: a three-layer NN is used to construct the observer which can be applied to systems with higher degrees of nonlinearity and without a priori knowledge of system dynamics, and a critic NN is employed to approximate the value function. The optimal control law is computed using the critic NN and the observer NN. Uniform ultimate boundedness of the closed-loop system is guaranteed. The actor, critic, and observer structures are all implemented in real-time, continuously and simultaneously. Finally, simulation results are presented to demonstrate the effectiveness of the proposed control scheme.

  3. E-mailed Evidence Based Summaries Impact Physician Learning More than Practice. A Review of: Grad, Roland M., Pierre Pluye, Jay Mercer, Bernard Marlow, Marie Eve Beauchamp, Michael Shulha, Janique Johnson-Lafleur and Sharon Wood-Dauphinee. “Impact of Research-based Synopses Delivered as Daily E-mail: A Prospective Observational Study.” Journal of the American Medical Informatics Association (2008)15.2: 240-5.

    OpenAIRE

    Hannigan, Gale G.

    2009-01-01

    Objective – To determine the use and construct validity of a method to assess the cognitive impact of information derived from daily e-mail evidence based summaries (InfoPOEMs), and to describe the self-reported impact of these InfoPOEMs.Design – Prospective, observational study over a period of 150 days employing a questionnaire and rating scale.Setting – This study was conducted via the Internet between September 8, 2006 and February 4, 2007.Subjects – Canadian Medical Association (CMA) mem...

  4. A numerical modeling study of a Montana thunderstorm: 1. Model results versus observations involving nonelectrical aspects

    Science.gov (United States)

    Helsdon, John H.; Farley, Richard D.

    1987-05-01

    A recently developed Storm Electrification Model (SEM) has been used to simulate the July 19, 1981, Cooperative Convective Precipitation Experiment (CCOPE) case study cloud. This part of the investigation examines the comparison between the model results and the observations of the actual cloud with respect to its nonelectrical aspects. A timing equivalence is established between the simulation and observations based on an explosive growth phase which was both observed and modeled. This timing equivalence is used as a basis upon which the comparisons are made. The model appears to do a good job of reproducing (in both space and time) many of the observed characteristics of the cloud. These include: (1) the general cloud appearance; (2) cloud size; (3) cloud top rise rate; (4) rapid growth phase; (5) updraft structure; (6) first graupel appearance; (7) first radar echo; (8) qualitative radar range-height indicator evolution; (9) cloud decay; and (10) the location of hydrometers with respect to the updraft/-downdraft structure. Some features that are not accurately modeled are the cloud base height, the maximum liquid water content, and the time from first formation of precipitation until it reaches the ground. While the simulation is not perfect, the faithfulness of the model results to the observations is sufficient to give us confidence that the microphysical processes active in this storm are adequately represented in the model physics. Areas where model improvement is indicated are also discussed.

  5. Effect of tracheostomy on pulmonary mechanics: An observational study

    OpenAIRE

    Sofi Khalid; Wani Tariq

    2010-01-01

    Background: This study was undertaken to find out the effect of early tracheostomy on weaning from mechanical ventilation. Pulmonary mechanics and arterial blood gases were assessed before and after tracheostomy in patients with severe head injury (Glasgow coma score < 8) requiring prolonged mechanical ventilation. Patients and Methods: The study included 20 mechanically ventilated patients of either sex between 20 and 45 years of age, who had suffered brain injury due to head trauma du...

  6. Evaluation of satellite soil moisture products over Norway using ground-based observations

    Science.gov (United States)

    Griesfeller, A.; Lahoz, W. A.; Jeu, R. A. M. de; Dorigo, W.; Haugen, L. E.; Svendby, T. M.; Wagner, W.

    2016-03-01

    In this study we evaluate satellite soil moisture products from the advanced SCATterometer (ASCAT) and the Advanced Microwave Scanning Radiometer - Earth Observing System (AMSR-E) over Norway using ground-based observations from the Norwegian water resources and energy directorate. The ASCAT data are produced using the change detection approach of Wagner et al. (1999), and the AMSR-E data are produced using the VUA-NASA algorithm (Owe et al., 2001, 2008). Although satellite and ground-based soil moisture data for Norway have been available for several years, hitherto, such an evaluation has not been performed. This is partly because satellite measurements of soil moisture over Norway are complicated owing to the presence of snow, ice, water bodies, orography, rocks, and a very high coastline-to-area ratio. This work extends the European areas over which satellite soil moisture is validated to the Nordic regions. Owing to the challenging conditions for soil moisture measurements over Norway, the work described in this paper provides a stringent test of the capabilities of satellite sensors to measure soil moisture remotely. We show that the satellite and in situ data agree well, with averaged correlation (R) values of 0.72 and 0.68 for ASCAT descending and ascending data vs in situ data, and 0.64 and 0.52 for AMSR-E descending and ascending data vs in situ data for the summer/autumn season (1 June-15 October), over a period of 3 years (2009-2011). This level of agreement indicates that, generally, the ASCAT and AMSR-E soil moisture products over Norway have high quality, and would be useful for various applications, including land surface monitoring, weather forecasting, hydrological modelling, and climate studies. The increasing emphasis on coupled approaches to study the earth system, including the interactions between the land surface and the atmosphere, will benefit from the availability of validated and improved soil moisture satellite datasets, including those

  7. Closed loop observer-based parameter estimation of quantum systems with a single population measurement

    OpenAIRE

    Leghtas, Zaki

    2008-01-01

    An observer-based Hamiltonian identification algorithm for quantum systems has been proposed by Bonnabel-et-al [2]. In this paper we propose another observer enabling the identification of the dipole moments of a multi-level case, and having access to the population of the ground state only.

  8. Speech-based recognition of self-reported and observed emotion in a dimensional space

    NARCIS (Netherlands)

    Truong, Khiet P.; Leeuwen, van David A.; Jong, de Franciska M.G.

    2012-01-01

    The differences between self-reported and observed emotion have only marginally been investigated in the context of speech-based automatic emotion recognition. We address this issue by comparing self-reported emotion ratings to observed emotion ratings and look at how differences between these two t

  9. HEMATOLOGICAL MANIFESTATIONS IN DENGUE FEVER – AN OBSERVATIONAL STUDY

    Directory of Open Access Journals (Sweden)

    Malathesha

    2014-02-01

    Full Text Available BACKGROUND: Dengue is a major preventable and treatable cause of morbidity and mortality among children and adults that occurs mainly in tropical and subtropical regions. Early diagnosis of dengue is important for provision of specific care which ensures marked reduction in the morbidity of the disease itself. OBJECTIVE: To evaluate hematological changes in serologically proven patients with clinical manifestations of Dengue in Bapuji & Chigateri Hospital, Davangere. METHODS: Clinical, hematological and serological information from Patients diagnosed with dengue infection in Bapuji & Chigateri hospital Davangere from April 2013 -June 2013. RESULTS: 221 cases of classic dengue predominated (90.2%, with mild clinical manifestations lacking complications. The main hematological findings were raised hematocrit (79.6%, lymphocytosis (66% monocytosis (84.6%, basophilia (52.9%, thrombocytopenia (100% and atypical lymphocytes (87%. In dengue hemorrhagic fever, thrombocytopenia was more prolonged and the number of atypical lymphocytes was higher, while the other hematological abnormalities presented daily evolution similar to those in classic dengue. The hematological changes observed in dengue presented according to the clinical course of the disease and its severity

  10. Imaging-based observations of low-latitude auroras during 2001-2004 at Nayoro, Japan

    Science.gov (United States)

    Suzuki, Hidehiko; Chino, Haruka; Sano, Yasuo; Kadokura, Akira; Ejiri, Mitsumu K.; Taguchi, Makoto

    2015-07-01

    Color images of six low-latitude auroral events observed using color digital cameras at Nayoro (142.5° E, 44.4° N), Hokkaido, Japan, from 2001 to 2004, were analyzed to determine the events' locations and times of occurrence. Geographical azimuthal and elevation angles of the images' pixels were determined precisely by using the positions of the stars captured in the images. Horizontal regions covered by these auroral events were directly indicated by mapping the color images onto geographical maps and assuming that the emission layer's altitude is the lowest or highest value of a visible-level red aurora, as determined by the OI 630.0nm emission. The estimated geomagnetic latitudes and L values of these low-latitude auroral events were in the 39-50° range and below L reported previously based on high-sensitivity optical observations at other sites on Hokkaido (Rikubetsu and Moshiri). Although the previous study is lacking information about the maximal brightness level of the red auroral events, the present investigation suggests that these four low-latitude auroral events reached the visible level. In addition, two new events were reported in this study. The present work provides essential information such as the morphology and appearance of visible auroras, which are extremely rare in mid- or low-latitude regions.

  11. Space-based observations of fire NOx emission coefficients: a global biome-scale comparison

    Directory of Open Access Journals (Sweden)

    A. K. Mebust

    2013-08-01

    Full Text Available Biomass burning represents both a significant and highly variable source of NOx to the atmosphere. This variability stems from both the episodic nature of fires, and from fire conditions such as the modified combustion efficiency of the fire, the nitrogen content of the fuel and possibly other factors that have not been identified or evaluated by comparison with observations. Satellite instruments offer an opportunity to observe emissions from wildfires, providing a large suite of measurements which allow us to study mean behavior and variability on the regional scale in a statistically rigorous manner. Here we use space-based measurements of fire radiative power from the Moderate Resolution Imaging Spectroradiometer in combination with NO2 tropospheric column densities from the Ozone Monitoring Instrument to measure mean emission coefficients (ECs in g NO MJ−1 from fires for global biomes, and across a wide range of smaller-scale ecoregions, defined as spatially-distinct clusters of fires with similar fuel type. Mean ECs for all biomes fall between 0.250–0.362 g NO MJ−1, a range that is smaller than found in previous studies of biome-scale emission factors. The majority of ecoregion ECs fall within or near this range, implying that under most conditions, mean fire emissions per unit energy are similar between different regions regardless of fuel type or spatial variability. In contrast to these similarities, we find that about 24% of individual ecoregion ECs deviate significantly (p x emissions.

  12. An Observational Study of Co-Rumination in Adolescent Friendships

    Science.gov (United States)

    Rose, Amanda J.; Schwartz-Mette, Rebecca A.; Glick, Gary C.; Smith, Rhiannon L.; Luebbe, Aaron M.

    2014-01-01

    Co-rumination is a dyadic process between relationship partners that refers to excessively discussing problems, rehashing problems, speculating about problems, mutual encouragement of problem talk, and dwelling on negative affect. Although studies have addressed youths' "tendency" to co-ruminate, little is known about the nature of…

  13. BACTERIOLOGICAL PROFILE OF SURGICAL PERITONITIS: A PROSPECTIVE OBSERVATIONAL STUDY

    Directory of Open Access Journals (Sweden)

    Manju

    2015-09-01

    Full Text Available Peritonitis is defined as inflammation of peritoneum that lines the abdominal cavity and the organs contained therein. In Surgical practice we most often encounter cases of peritonitis which are mostly secondary to hollow viscous perforation. Purpose of our study is to find out which type of peritonitis is more common in our institute, which is the most common bacteria isolated from peritoneal fluid and which antibiotic is it most sensitive to. We studied 104 cases o f age group 16 and above of both sex who presented with clinical features of peritonitis. Peritoneal fluid was obtained and sent for culture and sensitivity. Peritoneal fluid culture was positive in 55.76% cases. The incidence of culture positivity increas ed with duration of presentation. Gastro duodenal perforation was the most common etiological factor for peritonitis found in 42.86% cases followed by ileal perforation. E. c oli was the most common bacteria isolated in study group followed by klebsiella. M ost of the cultures were monomicrbial. E. coli was sensitive to amikacin, imipenem and meropenem (100%. So in our study Gram negative infection is more common in surgical peritonitis. Identification of bacteria and its sensitivity to the antibiotics is he lpful to avoid injudicious use of antibiotics in surgical peritonitis. Proper choice of antibiotics along with surgical management and proper resuscitation in cases of surgical peritonitis can reduces mortality and morbidity associated with these high risk cases

  14. Staff Reactions to Challenging Behaviour: An Observation Study

    Science.gov (United States)

    Lambrechts, Greet; Van Den Noortgate, Wim; Eeman, Lieve; Maes, Bea

    2010-01-01

    Staff reactions play an important role in the development and maintaining of clients' challenging behaviour. Because there is a paucity of research on staff reactions in naturalistic settings, this study examined sequential associations between challenging behaviour and staff reactions by means of a descriptive analysis. We analysed video…

  15. Interplanetary Charged Dust Magnetic Clouds Striking the Magnetosphere: Coordinated Space-based and Ground-based Observations

    Science.gov (United States)

    Russell, C. T.; Chi, Peter; Lai, Hairong

    In general, asteroids, meteoroids and dust do not interact with the plasma structures in the solar system, but after a collision between fast moving bodies the debris cloud contains nanoscale dust particles that are charged and behave like heavy ions. Dusty magnetic clouds are then accelerated to the solar wind speed. While they pose no threat to spacecraft because of the particle size, the coherency imposed by the magnetization of the cloud allows the cloud to interact with the Earth’s magnetosphere as well as the plasma in the immediate vicinity of the cloud. We call these clouds Interplanetary Field Enhancements (IFEs). These IFEs are a unique class of interplanetary field structures that feature cusp-shaped increases and decreases in the interplanetary magnetic field and a thin current sheet. The occurrence of IFEs is attributed to the interaction between the solar wind and dust particles produced in inter-bolide collisions. Previous spacecraft observations have confirmed that IFEs move with the solar wind. When IFEs strike the magnetosphere, they may distort the magnetosphere in several possible ways, such as producing a small indentation, a large scale compression, or a glancing blow. In any event if the IFE is slowed by the magnetosphere, the compression of the Earth’s field should be seen in the ground-based magnetic records that are continuously recorded. Thus it is important to understand the magnetospheric response to IFE arrival. In this study, we investigate the IFE structure observed by spacecraft upstream of the magnetosphere and the induced magnetic field perturbations observed by networks of ground magnetometers, including the THEMIS, CARISMA, McMAC arrays in North America and the IMAGE array in Europe. We find that, in a well-observed IFE event on December 24, 2006, all ground magnetometer stations observed an impulse at approximately 1217 UT when the IFE was expected to arrive at the Earth’s magnetopause. These ground stations spread across

  16. Periodontal disease and risk of chronic obstructive pulmonary disease: a meta-analysis of observational studies.

    Directory of Open Access Journals (Sweden)

    Xian-Tao Zeng

    Full Text Available BACKGROUND: Many epidemiological studies have found a positive association between periodontal disease (PD and risk of chronic obstructive pulmonary disease (COPD, but this association is varied and even contradictory among studies. We performed a meta-analysis to ascertain the relationship between PD and COPD. METHODS: PubMed and Embase database were searched up to January 10, 2012, for relevant observational studies on the association between PD and risk of COPD. Data from the studies selected were extracted and analyzed independently by two authors. The meta-analysis was performed using the Comprehensive Meta-Analysis software. RESULTS: Fourteen observational studies (one nested case-control, eight case-control, and five cross-sectional involving 3,988 COPD patients were yielded. Based on random-effects meta-analysis, a significant association between PD and COPD was identified (odds ratio = 2.08, 95% confidence interval = 1.48-2.91; P<0.001, with sensitivity analysis showing that the result was robust. Subgroups analyses according to study design, ethnicity, assessment of PD/COPD, and adjusted/unadjusted odds ratios also revealed a significant association. Publication bias was detected. CONCLUSIONS: Based on current evidence, PD is a significant and independent risk factor of COPD. However, whether a causal relationships exists remains unclear. Morever, we suggest performing randomized controlled trails to explore whether periodontal interventions are beneficial in regulating COPD pathogenesis and progression.

  17. Periodontal disease and risk of head and neck cancer: a meta-analysis of observational studies.

    Directory of Open Access Journals (Sweden)

    Xian-Tao Zeng

    Full Text Available BACKGROUND: Many epidemiological studies have found a positive association of periodontal disease (PD with risk of head and neck cancer (HNC, but the findings are varied or even contradictory. In this work, we performed a meta-analysis to ascertain the relationship between PD and HNC risk. METHODS: We searched the PubMed, Embase, and Cochrane Library databases for relevant observational studies on the association between PD and HNC risk published up to March 23, 2013. Data from the included studies were extracted and analyzed independently by two authors. Meta-analysis was performed using RevMan 5.2 software. RESULTS: We obtained seven observational studies involving two cohort and six case-control studies. Random-effects meta-analysis indicated a significant association between PD and HNC risk (odds ratio = 2.63, 95% confidence interval = 1.1.68 - 4.14; p < 0.001, with sensitivity analysis showing that the result was robust. Subgroup analyses based on adjustment for covariates, study design, PD assessment, tumor site, and ethnicity also revealed a significant association. CONCLUSIONS: Based on currently evidence, PD is probably a significant and independent risk factor of HNC.

  18. OBSERVATIONAL STUDY OF LIGHTNING CHARACTERISTICS IN HAIL-PRODUCING CLOUDS

    Institute of Scientific and Technical Information of China (English)

    LI Zhao-rong; FU Shuang-xi; LI Bao-zi; JIANG Lin

    2006-01-01

    @@ 1 INTRODUCTION Lightning is a phenomenon of atmospheric electricity with convective storms. Since the 1960's, its characteristics during weather processes of torrential rain, hails and tornadoes have been widely studied and a lot of attempts made to probe into the mechanisms responsible for the formation of lightning[1], giving rise to two theories explaining the lightning genesis, from the points of convection and ice-phase precipitation,respectively.

  19. Intraaortic Balloon Pump Counterpulsation and Cerebral Autoregulation: an observational study

    OpenAIRE

    Boots Rob; Barnett Adrian G; Timms Daniel; Dunster Kimble; Geng Shureng; Bellapart Judith; Fraser John F

    2010-01-01

    Abstract Background The use of Intra-aortic counterpulsation is a well established supportive therapy for patients in cardiac failure or after cardiac surgery. Blood pressure variations induced by counterpulsation are transmitted to the cerebral arteries, challenging cerebral autoregulatory mechanisms in order to maintain a stable cerebral blood flow. This study aims to assess the effects on cerebral autoregulation and variability of cerebral blood flow due to intra-aortic balloon pump and in...

  20. Renal colic, where is it headed? An observational study

    OpenAIRE

    Paolo Beltrami; Andrea Guttilla; Lorenzo Ruggera; Patrizia Bernich; Filiberto Zattoni

    2016-01-01

    Aim: In the last thirty years, the treatment for renal and ureteral calculi has undergone profound variations. The objective of this study has been to evaluate the existence of parameters which can affect the spontaneous expulsion of a symptomatic ureteral stone in a reasonably brief period of time and to identify whether certain parameters such as sex, age, the location and dimension of the stone, the presence of dilation in the urinary tract together with the administered therapy, can be us...

  1. ORPOM model for optimum distribution of tree ring sampling based on the climate observation network

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Tree ring dating plays an important role in obtaining past climate information.The fundamental study of obtaining tree ring samples in typical climate regions is particularly essential.The optimum distribution of tree ring sampling sites based on climate information from the Climate Observation Network(ORPOM model) is presented in this article.In this setup,the tree rings in a typical region are used for surface representation,by applying excellent correlation with the climate information as the main principle.Taking the Horqin Sandy Land in the cold and arid region of China as an example,the optimum distribution range of the tree ring sampling sites was obtained through the application of the ORPOM model,which is considered a reasonably practical scheme.

  2. Quality of Life after Stapled Hemorrhoidopexy: A Prospective Observational Study

    Directory of Open Access Journals (Sweden)

    Pankaj Kumar Garg

    2013-01-01

    Full Text Available Objective. The objective of the study was to assess the change in quality of life (QOL of patients undergoing stapled hemorrhoidopexy (SH using WHO Quality of Life-BREF (WHOQOL-BREF questionnaire. Methods. The study sample comprised patients with symptomatic II, III, and IV degree hemorrhoids, undergoing SH. The patients were asked to complete WHOQOL-BREF questionnaire before and one month following the surgery. Result. There were 20 patients in the study group. The postoperative pain score measured by visual analogue scale at six hours postoperatively was at 24 hours. The items in the WHOQOL-BREF had high-internal consistency or reliability as shown by high Cronbach's alpha coefficient which was 0.82 and 0.90 for pre- and postoperative questionnaires. There was significant improvement in the overall perception of QOL and health, and in physical and psychological domains. There was modest improvement in environmental domain, while no change was noted in social domain. Conclusion. SH improved the quality of life of patients treated for hemorrhoids.

  3. Disseminated intravascular coagulation or acute coagulopathy of trauma shock early after trauma? A prospective observational study

    DEFF Research Database (Denmark)

    Johansson, Per Ingemar; Sorensen, Anne Marie; Perner, Anders;

    2011-01-01

    ABSTRACT: INTRODUCTION: It is debated whether the early trauma induced coagulopathy (TIC) in severely injured patients reflects disseminated intravascular coagulation (DIC) with a fibrinolytic phenotype, acute coagulopathy of trauma shock (ACoTS) or yet other entities. This study investigated the...... prevalence of overt DIC and ACoTS in trauma patients and characterized these conditions based on their biomarker profiles. METHODS: Observational study at a single Level I Trauma Centre. Inclusion of 80 adult trauma patients ([greater than or equal to]18 years) who met criteria for full trauma team...

  4. Studying Sensing-Based Systems

    DEFF Research Database (Denmark)

    Kjærgaard, Mikkel Baun

    2013-01-01

    Recent sensing-based systems involve a multitude of users, devices, and places. These types of systems challenge existing approaches for conducting valid system evaluations. Here, the author discusses such evaluation challenges and revisits existing system evaluation methodologies.......Recent sensing-based systems involve a multitude of users, devices, and places. These types of systems challenge existing approaches for conducting valid system evaluations. Here, the author discusses such evaluation challenges and revisits existing system evaluation methodologies....

  5. Ethical issues for radiographers: general observations and a pilot qualitative study.

    Science.gov (United States)

    Gruppetta, Edward

    2009-07-01

    This paper is based on general observation arising from many years experience in managing and delivering radiography services in the health service. In addition, it presents the results of a pilot qualitative study based on unstructured interviews. The interviews were undertaken with a view to identifying the reasons for radiography that may not be well justified. The study was undertaken in the public and private sectors and many of the reasons are shared by both. The reasons for poor justification include: inadequate radiation protection education for referrers; avoidance of medical litigation; defensive medicine attitude by referrers and, in the private sector, pursuit of profit. The study provides a starting point for further more quantitative investigations that are clearly required in the area. PMID:19525503

  6. Ethical issues for radiographers: General observations and a pilot qualitative study

    International Nuclear Information System (INIS)

    This paper is based on general observation arising from many years experience in managing and delivering radiography services in the health service. In addition, it presents the results of a pilot qualitative study based on unstructured interviews. The interviews were undertaken with a view to identifying the reasons for radiography that may not be well justified. The study was undertaken in the public and private sectors and many of the reasons are shared by both. The reasons for poor justification include: inadequate radiation protection education for referrers; avoidance of medical litigation; defensive medicine attitude by referrers and, in the private sector, pursuit of profit. The study provides a starting point for further more quantitative investigations that are clearly required in the area. (authors)

  7. An Optimal-Estimation-Based Aerosol Retrieval Algorithm Using OMI Near-UV Observations

    Science.gov (United States)

    Jeong, U; Kim, J.; Ahn, C.; Torres, O.; Liu, X.; Bhartia, P. K.; Spurr, R. J. D.; Haffner, D.; Chance, K.; Holben, B. N.

    2016-01-01

    An optimal-estimation(OE)-based aerosol retrieval algorithm using the OMI (Ozone Monitoring Instrument) near-ultraviolet observation was developed in this study. The OE-based algorithm has the merit of providing useful estimates of errors simultaneously with the inversion products. Furthermore, instead of using the traditional lookup tables for inversion, it performs online radiative transfer calculations with the VLIDORT (linearized pseudo-spherical vector discrete ordinate radiative transfer code) to eliminate interpolation errors and improve stability. The measurements and inversion products of the Distributed Regional Aerosol Gridded Observation Network campaign in northeast Asia (DRAGON NE-Asia 2012) were used to validate the retrieved aerosol optical thickness (AOT) and single scattering albedo (SSA). The retrieved AOT and SSA at 388 nm have a correlation with the Aerosol Robotic Network (AERONET) products that is comparable to or better than the correlation with the operational product during the campaign. The OEbased estimated error represented the variance of actual biases of AOT at 388 nm between the retrieval and AERONET measurements better than the operational error estimates. The forward model parameter errors were analyzed separately for both AOT and SSA retrievals. The surface reflectance at 388 nm, the imaginary part of the refractive index at 354 nm, and the number fine-mode fraction (FMF) were found to be the most important parameters affecting the retrieval accuracy of AOT, while FMF was the most important parameter for the SSA retrieval. The additional information provided with the retrievals, including the estimated error and degrees of freedom, is expected to be valuable for relevant studies. Detailed advantages of using the OE method were described and discussed in this paper.

  8. Oral and dental health in Huntington's disease - an observational study

    OpenAIRE

    Saft, Carsten; Andrich, Jürgen; Müller, Thomas; Becker, Julia; Jackowski, Jochen

    2013-01-01

    Background Only a few case reports and case series dealing with oral and dental health care are available in literature until now. The aim of the present pilot study was to determine the status of dental health in comparison to matched controls and to heighten the neurologists’ and dentists’ awareness of the oral aspects of the disease. Methods 42 Huntington’s disease (HD) participants were scored according to the Unified Huntington’s Disease Rating Scale. The dental status was assessed by us...

  9. URINARY TRACT INFECTIONS IN MALE CHILDREN: A PROSPECTIVE OBSERVATIONAL STUDY

    OpenAIRE

    Sarada G; Rafiq Ahmed K; Sudhakar G* and Srilatha

    2015-01-01

    A total of 96 male children with Urinary Tract Infections (UTI) were included in the study to identify the risk factors predisposing to UTI in male children .78.83%  were in <1 yr age and 20.3% were in 1 to 5 yr of age. Dysuria, fever and frequency are the most common symptoms (33%). Culture positivity was only in 35 children (36.36%). E.coli was the most common organism isolated (80%). Urinary tract abnormalities were found in 34/96 (33%). Phimosis was the most common urinary anomaly note...

  10. Harvesting Collective Trend Observations from Large Scale Study Trips

    DEFF Research Database (Denmark)

    Eriksen, Kaare; Ovesen, Nis

    2014-01-01

    To enhance industrial design students’ decoding and understanding of the technological possibilities and the diversity of needs and preferences in different cultures it is not unusual to arrange study trips where such students acquire a broader view to strengthen their professional skills and...... numbers of students to the annual Milan Design Week and the Milan fair ‘I Saloni’ in Italy. The present paper describes and evaluates the method, the theory behind it, the practical execution of the trend registration, the results from the activities and future perspectives....

  11. Longitudinal Analyses of Early Lesions by Fluorescence: An Observational Study

    OpenAIRE

    Ferreira Zandoná, A.; Ando, M.; Gomez, G.F.; Garcia-Corretjer, M.; Eckert, G.J.; Santiago, E; Katz, B P; Zero, D.T.

    2013-01-01

    Previous caries experience correlates to future caries risk; thus, early identification of lesions has importance for risk assessment and management. In this study, we aimed to determine if Quantitative Light-induced Fluorescence (QLF) parameters—area (A [mm2]), fluorescence loss (∆F [%]), and ∆Q [%×mm2]—obtained by image analyses can predict lesion progression. We secured consent from 565 children (from 5-13 years old) and their parents/guardians and examined them at baseline and regular int...

  12. Biomass burning emissions estimated with a global fire assimilation system based on observed fire radiative power

    Directory of Open Access Journals (Sweden)

    J. W. Kaiser

    2012-01-01

    Full Text Available The Global Fire Assimilation System (GFASv1.0 calculates biomass burning emissions by assimilating Fire Radiative Power (FRP observations from the MODIS instruments onboard the Terra and Aqua satellites. It corrects for gaps in the observations, which are mostly due to cloud cover, and filters spurious FRP observations of volcanoes, gas flares and other industrial activity. The combustion rate is subsequently calculated with land cover-specific conversion factors. Emission factors for 40 gas-phase and aerosol trace species have been compiled from a literature survey. The corresponding daily emissions have been calculated on a global 0.5° × 0.5° grid from 2003 to the present. General consistency with the Global Fire Emission Database version 3.1 (GFED3.1 within its accuracy is achieved while maintaining the advantages of an FRP-based approach: GFASv1.0 makes use of the quantitative information on the combustion rate that is contained in the FRP observations, and it detects fires in real time at high spatial and temporal resolution. GFASv1.0 indicates omission errors in GFED3.1 due to undetected small fires. It also exhibits slightly longer fire seasons in South America and North Africa and a slightly shorter fire season in Southeast Asia. GFASv1.0 has already been used for atmospheric reactive gas simulations in an independent study, which found good agreement with atmospheric observations. We have performed simulations of the atmospheric aerosol distribution with and without the assimilation of MODIS aerosol optical depth (AOD. They indicate that the emissions of particulate matter need to be boosted by a factor of 2–4 to reproduce the global distribution of organic matter and black carbon. This discrepancy is also evident in the comparison of previously published top-down and bottom-up estimates. For the time being, a global enhancement of the particulate matter emissions by 3.4 is recommended. Validation with independent AOD and PM10

  13. Correlation between ground-based observations of substorm signatures and magnetotail dynamics

    Directory of Open Access Journals (Sweden)

    E. Borälv

    2005-03-01

    Full Text Available We present a substorm event study using the four Cluster spacecraft in combination with ground-based instruments, in order to perform simultaneous observations in the ionosphere and magnetotail. We show good correlation between substorm signatures on the ground and in the magnetotail, even though data from the northern-ground and southern-tail hemispheres are compared. During this event ground-based magnetometers show a substorm onset over Scandinavia in the pre-midnight sector. Within 1.5h the onset and three intensifications are apparent in the magnetograms. For all the substorm signatures seen on the ground, corresponding plasma sheet boundary motion is visible at Cluster, located at a downtail distance of 18.5 RE. As a result of the substorm onset and intensifications, Cluster moves in and out between the southern plasma sheet and lobe. Due to the lack of an apparent solar wind driver and the good correlation between substorm signatures on the ground, we conclude the substorm itself is the driver for these plasma sheet dynamics. We show that in the scales of Cluster inter-spacecraft distances (~0.5 RE the inferred plasma sheet motion is often directed in both Ygsm- and Zgsm-directions, and discuss this finding in the context of previous studies of tail flapping and plasma sheet thickness variations.

  14. Experimental research on an FFT based ultra-low current ripple observation system

    International Nuclear Information System (INIS)

    Background: The magnets exciting current ripple is required to be less than 10-6 for the proton medical accelerator under construction. Purpose: In order to observe the ultra-low current ripple, we design and set up a testing platform based on the ADC card used for digitalized power supplies. Methods: The system performance is analyzed, tested, and the observation is compared with the oscilloscope measurement. Results: Using this platform, the ultra-low current ripples are observed on several magnet power supplies. Conclusions: The method is experimentally proved suitable for the observation of current ripples of 10-6 versus hundreds DC current. (authors)

  15. An observational study on extraperitoneal caesarean section in present era

    Directory of Open Access Journals (Sweden)

    Sudhanshu Sekhara Nanda

    2014-06-01

    Full Text Available Background: This study was designed to find out the maternal and perinatal outcome in cases of extraperitoneal caesarean section. Total 100 women undergoing extraperitoneal cesarean section were included in the study. Methods: A detailed history taking, examination done and intra and post-operative parameters as per protocols were noted. Results: Success rate of extra peritoneal CS was 79.63%, Time taken from incision to delivery was and #8804;5 minutes in 60% cases, time taken from incision to closure was between 31-45 min in 67% cases, blood loss and #8804;500 ml in 58% cases, return of bowel function between 5-8 hours in 52%, mobilization within 24 hours in 52%, neonatal one minute APGAR score and #8805;7 in 90.91%. Conclusions: Extraperitoneal cesarean section can be applied as a surgical form of infection prophylaxis. Since it possesses a rational basis for the avoidance of serious post-operative pelvic infectious complications, this operation deserves reconsideration in the modern era. [Int J Reprod Contracept Obstet Gynecol 2014; 3(3.000: 724-727

  16. Effect of tracheostomy on pulmonary mechanics: An observational study

    Directory of Open Access Journals (Sweden)

    Sofi Khalid

    2010-01-01

    Full Text Available Background: This study was undertaken to find out the effect of early tracheostomy on weaning from mechanical ventilation. Pulmonary mechanics and arterial blood gases were assessed before and after tracheostomy in patients with severe head injury (Glasgow coma score < 8 requiring prolonged mechanical ventilation. Patients and Methods: The study included 20 mechanically ventilated patients of either sex between 20 and 45 years of age, who had suffered brain injury due to head trauma during admission (Glasgow coma scores of < 8. Mean airway pressure, peak airway pressure, plateau pressure, PaO 2 and PaCO 2 were measured 24 h before and after tracheostomy. Static and dynamic compliances were calculated. Results: Plateau airway pressures were not affected by tracheostomy, but peak airway pressure was reduced (29.90 ± 3.21 cm H 2 O before tracheostomy versus 24.30 ± 1.83 cm H 2 O after tracheostomy, P < 0.001. Dynamic compliance, but not static compliance, was improved by tracheostomy. Tracheostomy did not affect PaCO 2 , but it improved PaO 2 (83.09 ± 5.99 mmHg before versus 90.84 ± 5.61 mmHg after, P ≤ 0.001. Conclusions: The work of breathing through a tracheostomy tube may be less than through an endotracheal tube of same internal diameter.

  17. Change in neck circumference after shoulder arthroscopy: An observational study

    Directory of Open Access Journals (Sweden)

    Shrividya Chellam

    2015-01-01

    Full Text Available Background and Aims: Shoulder arthroscopy requires fluid irrigation, which causes soft-tissue oedema around chest, neck, and arm intraoperatively, leading to postoperative airway complications. We decided to study the incidence of increase in the neck circumference in shoulder arthroscopy and its effects on the airway. Methods: We studied 32 cases of shoulder arthroscopies over a period of 1-year, performed under general anaesthesia with interscalene block. The neck circumference of patients before and after the procedure was measured along with other parameters. The endotracheal tube cuff was deflated at the end of surgery to determine air leak around the tube. The negative leak test suggested airway oedema. Results: Thirty out of 32 patients showed positive air leak test. The average change in neck circumference was 1.17 ± 1.16 cm and all could be extubated uneventfully. Two showed negative leak test with an increase in neck circumference by 4.5 and 6.4 cm and were not extubated. Multiple regression analysis for risk factors showed intraoperative hypertension as a single predictor for an increase in neck circumference. Conclusion: Change in the neck circumference beyond 4 cm may suggest airway compromise and below 4 cm, airway compromise is unlikely even in the presence of extensive soft-tissue oedema around the shoulder, upper arm and chest.

  18. Renal colic, where is it headed? An observational study

    Directory of Open Access Journals (Sweden)

    Paolo Beltrami

    2016-03-01

    Full Text Available Aim: In the last thirty years, the treatment for renal and ureteral calculi has undergone profound variations. The objective of this study has been to evaluate the existence of parameters which can affect the spontaneous expulsion of a symptomatic ureteral stone in a reasonably brief period of time and to identify whether certain parameters such as sex, age, the location and dimension of the stone, the presence of dilation in the urinary tract together with the administered therapy, can be used for a correct clinical management of the patient. Methods: In a period of 9 months, 486 cases of renal colic were registered at emergency department. Results: The cases of renal colic due to ureteral calculus were 188 (38.7%. The patients’ charts, complete of all data and therefore, valid for this research, resulted to be 120 (64%. In the presence of a symptomatic ureteral stone, the correct approach must first of all, focalize on the dimension of the calculus itself; less importance instead, is given to the location, as reported in other studies, the presence of hydroureteronephrosis, sex and the side. Conclusion: In the cases when the pain symptoms cannot be solved by means of the administration of analgesics, it is then reasonable to take into consideration an immediate endourological treatment. If the pain symptoms are promptly solved, an attentive wait of 4 weeks should be considered reasonable in order to allow spontaneous expulsion of the calculus.

  19. Detection ability of space-based optical observation system to space debris

    Science.gov (United States)

    Zhao, Sisi; Ruan, Ningjuan; Zhuang, Xuxia

    2015-10-01

    For supplying the reference to the spaced-based optical observation system design and performance analysis, the space-based observation mode for space debris is established. Considering the geometry size, the material characteristics, and the distribution region of the debris, the visual magnitude of space debris is calculated in the condition of different detection range and different phase angle. Based on the typical instance, the simulation analysis of the space debris detection ability of space-based optical observation system, which is in LEO orbit and Sub-GEO orbit respectively, is carried out. The results show that the LEO spaced-based optical observation system having an aperture of 25cm can detect the LEO 3cm space debris, which is 100km far away and has the relative velocity of 1km/s, and can also detect the GEO 1m space object, which is 37000km far away and has the relative velocity of 4km/s. The Sub-GEO spaced-based optical observation system having an aperture of 25cm can detect the GEO 1cm space debris, which is 800km far away and has the relative velocity of 15m/s.

  20. Clinicohistopathological correlation of hysterectomy in rural India: an observational study

    Directory of Open Access Journals (Sweden)

    Kumud Gupta

    2015-04-01

    Full Text Available Background: Hysterectomy - abdominal or vaginal or laparoscopic assisted, hysterectomy is the most commonly performed elective major gynaecological surgery. Rate of hysterectomy has varied between 6.1 and 8.6/1000 women of all ages. The abdominal removal of the uterus is called and lsquo;total abdominal hysterectomy' while the removal of the uterus by the vaginal route is termed as and lsquo;vaginal hysterectomy'. The supracervical removal of the uterus is termed as and lsquo;subtotal hysterectomy'. As compared to a higher frequency of hysterectomy (10-20% in other countries, a lower rate (4-6% has been reported in India. Methods: The study was conducted in the department of obstetrics and gynaecology National Institute of Medical Sciences (NIMS, Jaipur in 2013-2014. 100 patients were undergoing hysterectomy. The patients were diagnosed on the basis of history, clinical examination and ultrasonography report. Results: In our study, maximum number of clinical diagnosis made, were of DUB (with PID and Prolapse which was 35%. This was followed by leiomyoma i.e. 29%, clinically 29 cases were diagnosed of which 24 were histopathologically proven. Adenomyosis (10%, clinically 10 cases were identified but there were 15 cases histopathologically, this can be due to different clinical presentation. Clinically diagnosed cases of carcinoma endometrium and cervical erosions were 1% and 2% respectively. Overall sensitivity for clinical diagnosis in our study was 52%. The most common histopathological finding was leiomyoma (24%, followed by adenomyosis (15% and chronic cervicitis (15%. Other pathologies include combined adenomyosis and leiomyoma (6%, benign ovarian cyst in four cases. Normal histopathological report was obtained in 32 cases. Maximum correlation (100% was found with cancer cervix, cancer ovary and cancer endometrium. Conclusions: Hysterectomy still remains the widely used modality in developing as well as developed countries. Every

  1. Funding sources for continuing medical education: An observational study

    Directory of Open Access Journals (Sweden)

    Ramesh Venkataraman

    2014-01-01

    Full Text Available Aims: Medical accreditation bodies and licensing authorities are increasingly mandating continuing medical education (CME credits for maintenance of licensure of healthcare providers. However, the costs involved in participating in these CME activities are often substantial and may be a major deterrent in obtaining these mandatory credits. It is assumed that healthcare providers often obtain sponsorship from their institutions or third party payers (i.e. pharmaceutical-industry to attend these educational activities. Data currently does not exist exploring the funding sources for CME activities in India. In this study, we examine the relative proportion of CME activities sponsored by self, institution and the pharmaceutical-industry. We also wanted to explore the characteristics of courses that have a high proportion of self-sponsorship. Materials and Methods: This is a retrospective audit of the data during the year 2009 conducted at an autonomous clinical training academy. The details of the sponsor of each CME activity were collected from an existing database. Participants were subsequently categorized as sponsored by self, sponsored by institution or sponsored by pharmaceutical-industry. Results: In the year 2009, a total of 2235 participants attended 40 different CME activities at the training academy. Of the total participants, 881 (39.4% were sponsored by self, 898 (40.2% were sponsored by institution and 456 (20.3% by pharmaceutical-industry. About 47.8% participants attended courses that carried an international accreditation. For the courses that offer international accreditation, 63.3% were sponsored by self, 34.9% were sponsored by institution and 1.6% were sponsored by pharmaceutical-industry. There were 126 participants (5.6% who returned to the academy for another CME activity during the study period. Self-sponsored (SS candidates were more likely to sponsor themselves again for subsequent CME activity compared with the other two

  2. UFOs in the LHC: Observations, studies and extrapolations

    CERN Document Server

    Baer, T; Cerutti, F; Ferrari, A; Garrel, N; Goddard, B; Holzer, EB; Jackson, S; Lechner, A; Mertens, V; Misiowiec, M; Nebot del Busto, E; Nordt, A; Uythoven, J; Vlachoudis, V; Wenninger, J; Zamantzas, C; Zimmermann, F; Fuster, N

    2012-01-01

    Unidentified falling objects (UFOs) are potentially a major luminosity limitation for nominal LHC operation. They are presumably micrometer sized dust particles which lead to fast beam losses when they interact with the beam. With large-scale increases and optimizations of the beam loss monitor (BLM) thresholds, their impact on LHC availability was mitigated from mid 2011 onwards. For higher beam energy and lower magnet quench limits, the problem is expected to be considerably worse, though. In 2011/12, the diagnostics for UFO events were significantly improved: dedicated experiments and measurements in the LHC and in the laboratory were made and complemented by FLUKA simulations and theoretical studies. The state of knowledge, extrapolations for nominal LHC operation and mitigation strategies are presented

  3. Observations on mattress covers: results of a pilot study.

    Science.gov (United States)

    Thomas, S

    1998-01-01

    Samples of covers from three commercially available mattresses were examined in the laboratory using test methods originally devised for testing surgical dressings. These revealed that although the covers shared many common features, there were differences in the conformability and tensile properties which may be of some clinical relevance. The study also confirmed that with some minor modifications, the experimental techniques used would be suitable for a future, more comprehensive review of mattress performance. In a separate investigation designed to examine the consequences of a failure of a mattress cover, the bioburden of a foam core removed from a damaged cover revealed the presence of very large numbers of microorganism, well in excess of 10(10) per gram of foam which could act as a recevoir of contamination and thus a source of cross infection. PMID:10531919

  4. Neoadjuvant Chemotherapy in Triple Negative Breast Cancer: An Observational Study.

    Science.gov (United States)

    Shao, Zhiying; Chaudhri, Shalini; Guo, Meng; Zhang, Longzhen; Rea, Daniel

    2016-01-01

    Triple negative breast cancer (TNBC) is a phenotype of breast cancer with aggressive clinical behavior. Because of the absence of optimal treatment, the prognosis of this disease is poor. The main purpose of this study was to detect the response to neoadjuvant chemotherapy (NACT) in a TNBC cohort and compare the long-term survival between patients with and without pathological complete response (pCR). A total of 53 patients diagnosed with TNBC from 2005 to 2013 who received NACT at the University Hospital Birmingham were enrolled in this study. Overall survival (OS) and progression-free survival (PFS) were compared between the pCR group and non-pCR group. Demographic information and clinical or pathologic parameters were also analyzed to explore potential predictive and prognostic factors. Fourteen patients (26.4%) achieved pCR to NACT. In univariate analysis, patients with pCR had longer PFS time (p = 0.013) and OS time (p = 0.054) compared with their counterparts without pCR. In multivariate analysis, the existence of lymphovascular invasion (LVI) significantly reduced OS (HR = 17.404, 95% CI = 2.923-103.644) and PFS (HR = 7.776, 95% CI = 1.645-36.753). The achievement of pCR to NACT can significantly postpone the incidence of disease progression in patients with TNBC. There is not enough evidence showing its influence on ultimate survival. LVI may be a more potent prognostic factor than pCR in the TNBC cohort. PMID:27131315

  5. Luenberger observer-based sensor fault detection: online application to DC motor

    OpenAIRE

    ALKAYA, Alkan; EKER, İlyas

    2014-01-01

    Fault detection and diagnosis (FDD) are very important for engineering systems in industrial applications. One of the most popular approaches is model-based fault detection. Recently, many techniques have been proposed in the FDD area. However, there are still very few reported applications or real-time implementations of the schemes. This paper presents online sensor FDD based on the model-based approach using a Luenberger observer and experimental application on a permanent magnet DC ...

  6. Thromboembolism in patients with immune thrombocytopenia (ITP): a meta-analysis of observational studies.

    Science.gov (United States)

    Langeberg, Wendy J; Schoonen, W Marieke; Eisen, Melissa; Gamelin, Laurence; Stryker, Scott

    2016-06-01

    This meta-analysis describes the incidence rate of arterial and venous thromboembolism (ATE and VTE) in patients with immune thrombocytopenia (ITP), and the relative risk of ATE and VTE in patients with ITP and comparable populations without ITP. MEDLINE and EMBASE were systematically searched for observational studies reporting incidence rates of ATE and VTE in populations with and without ITP between 1996 and 2013 [follow-up completed before thrombopoietin receptor (TPOr) agonists were commercially available]. Three large, population-based studies were identified from Denmark, the United Kingdom, and the United States. The incidence of ATE per 100 patient-years among patients with ITP ranged from 1.0 to 2.8, and among populations without ITP ranged from 0.7 to 1.8; the summary relative risk adjusted for matching factors (aRR) was 1.5 [95 % confidence interval (CI) 1.3, 1.8]. The incidence of VTE per 100 patient-years among patients with ITP ranged from 0.4 to 0.7, and among populations without ITP ranged from 0.1 to 0.4; the summary aRR (95 % CI) was 1.9 (1.4, 2.7). The risk of ATE and VTE among patients with ITP, based on evidence from three large, population-based observational studies, should be considered when evaluating the risk of thromboembolism attributed to ITP treatments, such as TPOr agonists. PMID:27084254

  7. An Approach for State Observation in Dynamical Systems Based on the Twisting Algorithm

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2013-01-01

    for the observation, not directly implying its applicability for state observation. However it is shown that in the discrete case this approach may be applied to obtain a real time derivative using an intermediate integral process. Furthermore, different types of gains for the algorithm are suggested...... and analyzed via Lyapunov arguments, and a special version of the observer is proposed specifically for hydraulic drives utilizing online available plant information. The proposed observer with different observer gains are subjected to simulation studies in order to evaluate the exact properties, and...

  8. Skin features in myotonic dystrophy type 1: an observational study.

    Science.gov (United States)

    Campanati, A; Giannoni, M; Buratti, L; Cagnetti, C; Giuliodori, K; Ganzetti, G; Silvestrini, M; Provinciali, L; Offidani, A

    2015-05-01

    Poor data regarding skin involvement in Myotonic Dystrophy, also named Dystrophia Myotonica type 1, have been reported. This study aimed to investigate the prevalence and types of skin disorders in adult patients with Myotonic Dystrophy type 1. Fifty-five patients and one hundred age- and sex-matched healthy subjects were referred to a trained dermatologist for a complete skin examination to check for potential cutaneous hallmarks of disease. No difference in prevalence of preneoplastic, neoplastic, and cutaneous lesions was detected between the two groups. Among morphofunctional, proliferative and inflammatory lesions, focal hyperhidrosis (p androgenic alopecia (p = 0.01), nail pitting (p = 0.003), pedunculus fibromas (p = 0. 01), twisted hair (p = 0.01), seborrheic dermatitis (p = 0.02), macules of hyperpigmentation (p = 0.03) were significantly more frequent in patients compared with controls. In patients with Myotonic Dystrophy type 1 significant differences according to sex were found for: early androgenic alopecia, twisted hair and seborrheic dermatitis, whose prevalence was higher in males (p < 0.0001). Our preliminary results seem to rule out an increased prevalence of pre-neoplastic, and neoplastic skin lesions in Myotonic Dystrophy type 1. On the other hand, an increased prevalence of morphofunctional, inflammatory, and proliferative diseases involving adnexal structures seems to characterize adult patients with Myotonic Dystrophy type 1. PMID:25813338

  9. Metaphors among titles of medical publications: an observational study

    Directory of Open Access Journals (Sweden)

    Philippa Mungra

    2007-10-01

    Full Text Available In this study, we attempted to determine the frequency and types of metaphors in a corpus of titles from a single medical journal collected over one year. The frequency of metaphor tokens (4.6% was highest among editorials and other opinion articles and consisted predominantly of primary metaphors, which require explanation using a visual, cultural or other physical vehicle. When the metaphor was used only in the title and not in the body of the text, as was common in letters to the editor or in editorials, the metaphor may constitute a para-textual device used for engaging the reader. Other metaphors among research article titles were present not only in the title, but also used repeatedly in the body of the text. Among these research articles, metaphors were frequently used to endow the focus words of the metaphor with a precise and meaningful significance which, when used repeatedly in the text, may constitute a mechanism by which sub-technical language or internal jargon may arise. Being syntactically simple but endowed with a high communicative import, titles as a text type may help improve academic literacy, among beginners.

  10. An Inverse Source Problem for a One-dimensional Wave Equation: An Observer-Based Approach

    KAUST Repository

    Asiri, Sharefa M.

    2013-05-25

    Observers are well known in the theory of dynamical systems. They are used to estimate the states of a system from some measurements. However, recently observers have also been developed to estimate some unknowns for systems governed by Partial differential equations. Our aim is to design an observer to solve inverse source problem for a one dimensional wave equation. Firstly, the problem is discretized in both space and time and then an adaptive observer based on partial field measurements (i.e measurements taken form the solution of the wave equation) is applied to estimate both the states and the source. We see the effectiveness of this observer in both noise-free and noisy cases. In each case, numerical simulations are provided to illustrate the effectiveness of this approach. Finally, we compare the performance of the observer approach with Tikhonov regularization approach.

  11. Aortic replacement in aorto-occlusive disease: an observational study

    Directory of Open Access Journals (Sweden)

    Winter Richard K

    2008-10-01

    Full Text Available Abstract Background For many patients with aorto-occlusive disease, where stent deployment is not possible, surgery remains the only treatment option available. The aim of this study was to assess the results of aortic reconstruction surgery performed in patients with critical ischaemia. Methods All patients with critical ischaemia undergoing surgery during 1991–2004 were identified from a prospectively maintained database. Mortality data was verified against death certificate data. Demographic and clinical data were obtained from the clinical notes and the radiology database. Disease was classified as: type I – limited to aorta and common iliac arteries; type II – external iliac disease and type III combined aortic, iliac and infra-inguinal disease. Results 86 patients underwent aortic replacement surgery all of whom had critical ischaemia consisting of: type I (n = 16; type II (n = 37 and type III (n = 33. The 30-day mortality rate was 10.4%, the one-year patient survival was 80%, and the 1-year graft survival was 80%. At 2 years the actual patient survival was 73% and no additional graft losses were identified. All patients surviving 30 days reported excellent symptomatic relief. Early, complications occurred in 6 (7% patients: thrombosis within diseased superficial femoral arteries (n = 4; haemorrhage and subsequent death (n = 2. Ten (14% late complications (> 12 months occurred in the 69 surviving patients and included: anastomotic stenosis (n = 3; graft thrombosis (n = 4, graft infection (n = 3. Four patients developed claudication as a result of more distal disease in the presence of a patent graft, and 1 patient who continued smoking required an amputation for progressive distal disease. Conclusion Aortic reconstruction for patients with extensive aorto-occlussive disease provides long-standing symptomatic relief for the majority of patients. After the first year, there is continued patient attrition due to co

  12. Ground-based observations of uranus and neptune using CCD instruments

    International Nuclear Information System (INIS)

    The author verifies that with the help of charge-coupled devices (CCD) great progress is being made in ground-based astronomical observations, including the study of the remote giant planets Uranus and Neptune. In reading the CCD the top row of pixels (potential wells) is moved into the sequential (shift) reading register; after this each row (line) of pixels moves its electrons upward (in each column) until the bottom row is cleared. This process is repeated for each row until the device is interrogated sequentially. The use of CCD detectors for purposes of image acquisition and spectroscopy has already found wide popularity at astronomical observatories, and soon it will spread to space research. The first known attempts to use CCD to obtain astronomical images was made by the author and his colleagues in April 1976. The result was the first observations of structure on the dark disk of Uranus. In general, the more refined the mathematical provision, the more information can be extracted from the images or spectra

  13. Aircraft-based observations and high-resolution simulations of an Icelandic dust storm

    Directory of Open Access Journals (Sweden)

    A.-M. Blechschmidt

    2012-11-01

    Full Text Available The first aircraft-based observations of an Icelandic dust storm are presented. The measurements were carried out over the ocean near Iceland's south coast in February 2007. This dust event occurred in conjunction with an easterly barrier jet of more than 30 m s−1. The aircraft measurements show high particle mass mixing ratios in an area of low wind speeds in the wake of Iceland near the coast, decreasing abruptly towards the jet. Simulations from the Weather Research and Forecasting Model coupled with Chemistry (WRF/Chem indicate that the measured high mass mixing ratios and observed low visibility inside the wake are due to dust transported from Icelandic sand fields towards the ocean. This is confirmed by meteorological station data. Glacial outwash terrains located near the Mýrdalsjökull glacier are among simulated dust sources. Sea salt aerosols produced by the impact of strong winds on the ocean surface started to dominate as the aircraft flew away from Iceland into the jet. The present results support recent studies which suggest that Icelandic deserts should be considered as important dust sources in global and regional climate models.

  14. Aircraft-based observations and high-resolution simulations of an Icelandic dust storm

    Directory of Open Access Journals (Sweden)

    A.-M. Blechschmidt

    2012-03-01

    Full Text Available The first aircraft-based observations of an Icelandic dust storm are presented. The measurements were carried out over the ocean near Iceland's south coast in February 2007. This dust event occurred in conjunction with an easterly barrier jet of more than 30 m s−1. The aircraft measurements show high particle mass mixing ratios in an area of low wind speeds in the wake of Iceland near the coast, decreasing abruptly towards the jet. Simulations from the Weather Research and Forecasting Model coupled with Chemistry (WRF/Chem indicate that the measured high mass mixing ratios and observed low visibility inside the wake are due to dust transported from Icelandic sand fields towards the ocean. This is confirmed by meteorological station data. Primary dust sources are glacial outwash terrains located near the Mýrdalsjökull glacier. Sea salt aerosols produced by the impact of strong winds on the ocean surface started to dominate as the aircraft flew away from Iceland into the jet. The present results support recent studies which suggest that Icelandic deserts should be considered as important dust sources in global and regional climate models.

  15. Comparison of OMI UV observations with ground-based measurements at high northern latitudes

    Directory of Open Access Journals (Sweden)

    G. Bernhard

    2015-03-01

    Full Text Available The Dutch-Finnish Ozone Monitoring Instrument (OMI on board NASA's Aura spacecraft provides estimates of erythemal (sunburning ultraviolet (UV dose rates and erythemal daily doses. These data were compared with ground-based measurements at 13 stations located throughout the Arctic and Scandinavia from 60 to 83° N. The study corroborates results from earlier work, but is based on a longer time series (eight vs. two years and considers additional data products, such as the erythemal dose rate at the time of the satellite overpass. Furthermore, systematic errors in satellite UV data resulting from inaccuracies in the surface albedo climatology used in the OMI UV algorithm are systematically assessed. At times when the surface albedo is correctly known, OMI data typically exceed ground-based measurements by 0–11%. When the OMI albedo climatology exceeds the actual albedo, OMI data may be biased high by as much as 55%. In turn, when the OMI albedo climatology is too low, OMI data can be biased low by up to 59%. Such large negative biases may occur when reflections from snow and ice, which increase downwelling UV irradiance, are misinterpreted as reflections from clouds, which decrease the UV flux at the surface. Results suggest that a better OMI albedo climatology would greatly improve the accuracy of OMI UV data products even if year-to-year differences of the actual albedo cannot be accounted for. A pathway for improving the OMI albedo climatology is discussed. Results also demonstrate that ground-based measurements from the center of Greenland, where high, homogenous surface albedo is observed year round, are ideally suited to detect systematic problems or temporal drifts in estimates of surface UV irradiance from space.

  16. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Statement

    DEFF Research Database (Denmark)

    von Elm, Erik; Altman, Douglas G; Egger, Matthias;

    2014-01-01

    Much biomedical research is observational. The reporting of such research is often inadequate, which hampers the assessment of its strengths and weaknesses and of a study's generalisability. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Initiative developed rec...

  17. Mars atmosphere studies with the SPICAM IR emission phase function observations

    Science.gov (United States)

    Trokhimovskiy, Alexander; Fedorova, Anna; Montmessin, Franck; Korablev, Oleg; Bertaux, Jean-Loup

    Emission Phase Function (EPF) observations is a powerful tool for characterization of atmosphere and surface. EPF sequence provides the extensive coverage of scattering angles above the targeted surface location which allow to separate the surface and aerosol scattering, study a vertical distribution of minor species and aerosol properties. SPICAM IR instrument on Mars Express mission provides continuous atmospheric observations in near IR (1-1.7 mu) in nadir and limb starting from 2004. For the first years of SPICAM operation only a very limited number of EPFs was performed. But from the mid 2013 (Ls=225, MY31) SPICAM EPF observations become rather regular. Based on the multiple-scattering radiative transfer model SHDOM, we analyze equivalent depths of carbon dioxide (1,43 mu) and water vapour (1,38 mu) absorption bands and their dependence on airmass during observation sequence to get aerosol optical depths and properties. The derived seasonal dust opacities from near IR can be used to retrieve the size distribution from comparison with simultaneous results of other instruments in different spectral ranges. Moreover, the EPF observations of water vapour band allow to access poorly known H2O vertical distribution for different season and locations.

  18. Replacing climatological potential evapotranspiration estimates with dynamic satellite-based observations in operational hydrologic prediction models

    Science.gov (United States)

    Franz, K. J.; Bowman, A. L.; Hogue, T. S.; Kim, J.; Spies, R.

    2011-12-01

    In the face of a changing climate, growing populations, and increased human habitation in hydrologically risky locations, both short- and long-range planners increasingly require robust and reliable streamflow forecast information. Current operational forecasting utilizes watershed-scale, conceptual models driven by ground-based (commonly point-scale) observations of precipitation and temperature and climatological potential evapotranspiration (PET) estimates. The PET values are derived from historic pan evaporation observations and remain static from year-to-year. The need for regional dynamic PET values is vital for improved operational forecasting. With the advent of satellite remote sensing and the adoption of a more flexible operational forecast system by the National Weather Service, incorporation of advanced data products is now more feasible than in years past. In this study, we will test a previously developed satellite-derived PET product (UCLA MODIS-PET) in the National Weather Service forecast models and compare the model results to current methods. The UCLA MODIS-PET method is based on the Priestley-Taylor formulation, is driven with MODIS satellite products, and produces a daily, 250m PET estimate. The focus area is eight headwater basins in the upper Midwest U.S. There is a need to develop improved forecasting methods for this region that are able to account for climatic and landscape changes more readily and effectively than current methods. This region is highly flood prone yet sensitive to prolonged dry periods in late summer and early fall, and is characterized by a highly managed landscape, which has drastically altered the natural hydrologic cycle. Our goal is to improve model simulations, and thereby, the initial conditions prior to the start of a forecast through the use of PET values that better reflect actual watershed conditions. The forecast models are being tested in both distributed and lumped mode.

  19. Relationship between Cloud Characteristics and Radar Reflectivity Based on Aircraft and Cloud Radar Co-observations

    Institute of Scientific and Technical Information of China (English)

    ZONG Rong; LIU Liping; YIN Yan

    2013-01-01

    Cloud properties were investigated based on aircraft and cloud radar co-observation conducted at Yitong,Jilin,Northeast China.The aircraft provided in situ measurements of cloud droplet size distribution,while the millimeter-wavelength cloud radar vertically scanned the same cloud that the aircraft penetrated.The reflectivity factor calculated from aircraft measurements was compared in detail with simultaneous radar observations.The results showed that the two reflectivities were comparable in warm clouds,but in ice cloud there were more differences,which were probably associated with the occurrence of liquid water.The acceptable agreement between reflectivities obtained in water cloud confirmed that it is feasible to derive cloud properties by using aircraft data,and hence for cloud radar to remotely sense cloud properties.Based on the dataset collected in warm clouds,the threshold of reflectivity to diagnose drizzle and cloud particles was studied by analyses of the probability distribution function of reflectivity from cloud particles and drizzle drops.The relationship between reflectivity factor (Z) and cloud liquid water content (LWC) was also derived from data on both cloud particles and drizzle.In comparison with cloud droplets,the relationship for drizzle was blurred by many scatter points and thus was less evident.However,these scatters could be partly removed by filtering out the drop size distribution with a large ratio of reflectivity and large extinction coefficient but small effective radius.Empirical relationships of Z-LWC for both cloud particles and drizzle could then be derived.

  20. Potential and limitations of multidecadal satellite soil moisture observations for selected climate model evaluation studies

    Directory of Open Access Journals (Sweden)

    A. Loew

    2013-09-01

    Full Text Available Soil moisture is an essential climate variable (ECV of major importance for land–atmosphere interactions and global hydrology. An appropriate representation of soil moisture dynamics in global climate models is therefore important. Recently, a first multidecadal, observation-based soil moisture dataset has become available that provides information on soil moisture dynamics from satellite observations (ECVSM, essential climate variable soil moisture. The present study investigates the potential and limitations of this new dataset for several applications in climate model evaluation. We compare soil moisture data from satellite observations, reanalysis and simulations from a state-of-the-art land surface model and analyze relationships between soil moisture and precipitation anomalies in the different dataset. Other potential applications like model parameter optimization or model initialization are not investigated in the present study. In a detailed regional study, we show that ECVSM is capable to capture well the interannual and intraannual soil moisture and precipitation dynamics in the Sahelian region. Current deficits of the new dataset are critically discussed and summarized at the end of the paper to provide guidance for an appropriate usage of the ECVSM dataset for climate studies.

  1. A novel space-based observation strategy for GEO objects based on daily pointing adjustment of multi-sensors

    Science.gov (United States)

    Hu, Yun-peng; Li, Ke-bo; Xu, Wei; Chen, Lei; Huang, Jian-yu

    2016-08-01

    Space-based visible (SBV) program has been proved to be with a large advantage to observe geosynchronous earth orbit (GEO) objects. With the development of SBV observation started from 1996, many strategies have come out for the purpose of observing GEO objects more efficiently. However it is a big challenge to visit all the GEO objects in a relatively short time because of the distribution characteristics of GEO belt and limited field of view (FOV) of sensor. And it's also difficult to keep a high coverage of the GEO belt every day in a whole year. In this paper, a space-based observation strategy for GEO objects is designed based on the characteristics of the GEO belt. The mathematical formula of GEO belt is deduced and the evolvement of GEO objects is illustrated. There are basically two kinds of orientation strategies for most observation satellites, i.e., earth-oriented and inertia-directional. Influences of both strategies to their own observation regions are analyzed and compared with each other. A passive optical instrument with daily attitude-adjusting strategies is proposed to increase the daily coverage rate of GEO objects in a whole year. Furthermore, in order to observe more GEO objects in a relatively short time, the strategy of a satellite with multi-sensors is proposed. The installation parameters between different sensors are optimized, more than 98% of GEO satellites can be observed every day and almost all the GEO satellites can be observed every two days with 3 sensors (FOV: 6° × 6°) on the satellite under the strategy of daily pointing adjustment in a whole year.

  2. The data platform of national special environment and disaster field observation stations based on grid environment

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The Data Platform of Resource and Environment-whose data mainly come from field observation stations,spatial observations,and internet service institutions-is the base of data analysis and model simulation in geoscience research in China.Among this integrated data platform,the tasks of the data platform of field observation stations are principally data collection,management,assimilation,and share service.Taking into consideration the distributing characteristics of the data sources and the service objects,the authors formulated the framework of the field observation stations’ data platform based on the grid technology and designed its operating processes.The authors have further defined and analyzed the key functions and implementing techniques for each module.In a Linux operating system,validation tests for the data platform’s function on data replication,data synchronization,and unified data service have been conducted under an environment that of the simulating field stations.

  3. Optimizing prescription of chinese herbal medicine for unstable angina based on partially observable markov decision process.

    Science.gov (United States)

    Feng, Yan; Qiu, Yu; Zhou, Xuezhong; Wang, Yixin; Xu, Hao; Liu, Baoyan

    2013-01-01

    Objective. Initial optimized prescription of Chinese herb medicine for unstable angina (UA). Methods. Based on partially observable Markov decision process model (POMDP), we choose hospitalized patients of 3 syndrome elements, such as qi deficiency, blood stasis, and turbid phlegm for the data mining, analysis, and objective evaluation of the diagnosis and treatment of UA at a deep level in order to optimize the prescription of Chinese herb medicine for UA. Results. The recommended treatment options of UA for qi deficiency, blood stasis, and phlegm syndrome patients were as follows: Milkvetch Root + Tangshen + Indian Bread + Largehead Atractylodes Rhizome (ADR = 0.96630); Danshen Root + Chinese Angelica + Safflower + Red Peony Root + Szechwan Lovage Rhizome Orange Fruit (ADR = 0.76); Snakegourd Fruit + Longstamen Onion Bulb + Pinellia Tuber + Dried Tangerine peel + Largehead Atractylodes Rhizome + Platycodon Root (ADR = 0.658568). Conclusion. This study initially optimized prescriptions for UA based on POMDP, which can be used as a reference for further development of UA prescription in Chinese herb medicine. PMID:24078826

  4. Predictive Factors for Anastomotic Leakage After Colorectal Surgery: Study Protocol for a Prospective Observational Study (REVEAL Study)

    Science.gov (United States)

    Bosmans, Joanna WAM; Kartal, Serdar; Lubbers, Tim; Sosef, Meindert; Slooter, Gerrit D; Stoot, Jan H; van Schooten, Frederik-Jan; Bouvy, Nicole D; Derikx, Joep PM

    2016-01-01

    Background Anastomotic leakage (AL) remains the most important complication following colorectal surgery, and is associated with high morbidity and mortality rates. Previous research has focused on identifying risk factors and potential biomarkers for AL, but the sensitivity of these tests remains poor. Objective This prospective multicenter observational study aims at combining multiple parameters to establish a diagnostic algorithm for colorectal AL. Methods This study aims to include 588 patients undergoing surgery for colorectal carcinoma. Patients will be eligible for inclusion when surgery includes the construction of a colorectal anastomosis. Patient characteristics will be collected upon consented inclusion, and buccal swabs, breath, stool, and blood samples will be obtained prior to surgery. These samples will allow for the collection of information regarding patients’ inflammatory status, genetic predisposition, and intestinal microbiota. Additionally, breath and blood samples will be taken postoperatively and patients will be strictly observed during their in-hospital stay, and the period shortly thereafter. Results This study has been open for inclusion since August 2015. Conclusions An estimated 8-10% of patients will develop AL following surgery, and they will be compared to non-leakage patients. The objectives of this study are twofold. The primary aim is to establish and validate a diagnostic algorithm for the pre-operative prediction of the risk of AL development using a combination of inflammatory, immune-related, and genetic parameters. Previously established risk factors and novel parameters will be incorporated into this algorithm, which will aid in the recognition of patients who are at risk for AL. Based on these results, recommendations can be made regarding the construction of an anastomosis or deviating stoma, and possible preventive strategies. Furthermore, we aim to develop a new algorithm for the post-operative diagnosis of AL at an

  5. Intermittent observer-based consensus control for multi-agent systems with switching topologies

    Science.gov (United States)

    Xu, Xiaole; Gao, Lixin

    2016-06-01

    In this paper, we focus on the consensus problem for leaderless and leader-followers multi-agent systems with periodically intermittent control. The dynamics of each agent in the system is a linear system, and the interconnection topology among the agents is assumed to be switching. We assume that each agent can only share the outputs with its neighbours. Therefore, a class of distributed intermittent observer-based consensus protocols are proposed for each agent. First, in order to solve this problem, a parameter-dependent common Lyapunov function is constructed. Using this function, we prove that all agents can access a prescribed value, under the designed intermittent controller and observer, if there are suitable conditions on communication. Second, based on the investigation of the leader-following consensus problem, we design a new distributed intermittent observer-based protocol for each following agent. Finally, we provide an illustrative example to verify the effectiveness of the proposed approach.

  6. Data Fusion Based on Optical Technology for Observation of Human Manipulation

    Science.gov (United States)

    Falco, Pietro; De Maria, Giuseppe; Natale, Ciro; Pirozzi, Salvatore

    2012-01-01

    The adoption of human observation is becoming more and more frequent within imitation learning and programming by demonstration approaches (PbD) to robot programming. For robotic systems equipped with anthropomorphic hands, the observation phase is very challenging and no ultimate solution exists. This work proposes a novel mechatronic approach to the observation of human hand motion during manipulation tasks. The strategy is based on the combined use of an optical motion capture system and a low-cost data glove equipped with novel joint angle sensors, based on optoelectronic technology. The combination of the two information sources is obtained through a sensor fusion algorithm based on the extended Kalman filter (EKF) suitably modified to tackle the problem of marker occlusions, typical of optical motion capture systems. This approach requires a kinematic model of the human hand. Another key contribution of this work is a new method to calibrate this model.

  7. Multi-viewpoint Smartphone AR-based Learning System for Solar Movement Observations

    Directory of Open Access Journals (Sweden)

    Ke Tian

    2014-06-01

    Full Text Available Understanding solar movement (e.g., solar diurnal motion is difficult for those are beginning to learn about astronomy. Previous research has revealed that observation-based learning can help make astronomical phenomena clearer to understand for such learners. In this research, Smartphone Augmented Reality (AR technology and 3D content were used to develop a multi-viewpoint Smartphone AR-based learning system (M-VSARLS for solar movement observations that can be used in the real-world environment. The goal of this research is to assess the usefulness of the system, usability of the AR function and 3D content, and the overall effect of the system on the learner’s motivation through task-based experiments with follow-up questionnaires. The results show that the M-VSARL system is effective in improving the observational skills and learning ability of learners, and in enhancing their motivation to learn about solar movement.

  8. Observing the Testing Effect using Coursera Video-recorded Lectures: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Paul Zhihao eYONG

    2016-01-01

    Full Text Available We investigated the testing effect in Coursera video-based learning. One hundred and twenty-three participants either (a studied an instructional video-recorded lecture four times, (b studied the lecture three times and took one recall test, or (c studied the lecture once and took three tests. They then took a final recall test, either immediately or a week later, through which their learning was assessed. Whereas repeated studying produced better recall performance than did repeated testing when the final test was administered immediately, testing produced better performance when the final test was delayed until a week after. The testing effect was observed using Coursera lectures. Future directions are documented.

  9. Fault Diagnosis of an Advanced Wind Turbine Benchmark using Interval-based ARRs and Observers

    DEFF Research Database (Denmark)

    Sardi, Hector Eloy Sanchez; Escobet, Teressa; Puig, Vicenc;

    2015-01-01

    This paper proposes a model-based fault diagnosis (FD) approach for wind turbines and its application to a realistic wind turbine FD benchmark. The proposed FD approach combines the use of analytical redundancy relations (ARRs) and interval observers. Interval observers consider an unknown but bo...... turbine using the National Renewable Energy Laboratory FAST simulator. The obtained results are presented and compared with that of other approaches proposed in the literature....

  10. A Sparse Representation-Based Deployment Method for Optimizing the Observation Quality of Camera Networks

    OpenAIRE

    Guangming Shi; Xiaotian Wang; Fei Qi; Chang Wang

    2013-01-01

    Deployment is a critical issue affecting the quality of service of camera networks. The deployment aims at adopting the least number of cameras to cover the whole scene, which may have obstacles to occlude the line of sight, with expected observation quality. This is generally formulated as a non-convex optimization problem, which is hard to solve in polynomial time. In this paper, we propose an efficient convex solution for deployment optimizing the observation quality based on a novel aniso...

  11. A Vehicle Haptic Steering by Wire System Based on High Gain GPI Observers

    OpenAIRE

    A. Rodriguez-Angeles; H. Sira-Ramirez; J. A. Garcia-Antonio

    2014-01-01

    A vehicle steering by wire (SBW) haptic system based on high gain generalized proportional integral (GPI) observers is introduced. The observers are considered for the estimation of dynamic perturbations that are present at the tire and steering wheel. To ensure efficient tracking between the commanded steering wheel angle and the tire orientation angle, the estimated perturbations are on line canceled. As to provide a haptic interface with the driver, the estimated dynamic effects at the st...

  12. Control and fault diagnosis based sliding mode observer of a multicellular converter: Hybrid approach

    KAUST Repository

    Benzineb, Omar

    2013-01-01

    In this article, the diagnosis of a three cell converter is developed. The hybrid nature of the system represented by the presence of continuous and discrete dynamics is taken into account in the control design. The idea is based on using a hybrid control and an observer-type sliding mode to generate residuals from the observation errors of the system. The simulation results are presented at the end to illustrate the performance of the proposed approach. © 2013 FEI STU.

  13. Meridian-scanning photometer, coherent HF radar, and magnetometer observations of the cusp: a case study

    Directory of Open Access Journals (Sweden)

    S. E. Milan

    Full Text Available The dynamics of the cusp region and post-noon sector for an interval of predominantly IMF By, Bz < 0 nT are studied with the CUTLASS Finland coherent HF radar, a meridian-scanning photometer located at Ny Ålesund, Svalbard, and a meridional network of magnetometers. The scanning mode of the radar is such that one beam is sampled every 14 s, and a 30° azimuthal sweep is completed every 2 minutes, all at 15 km range resolution. Both the radar backscatter and red line (630 nm optical observations are closely co-located, especially at their equatorward boundary. The optical and radar aurora reveal three different behaviours which can interchange on the scale of minutes, and which are believed to be related to the dynamic nature of energy and momentum transfer from the solar wind to the magnetosphere through transient dayside reconnection. Two interpretations of the observations are presented, based upon the assumed location of the open/closed field line boundary (OCFLB. In the first, the OCFLB is co-located with equatorward boundary of the optical and radar aurora, placing most of the observations on open field lines. In the second, the observed aurora are interpreted as the ionospheric footprint of the region 1 current system, and the OCFLB is placed near the poleward edge of the radar backscatter and visible aurora; in this interpretation, most of the observations are placed on closed field lines, though transient brightenings of the optical aurora occur on open field lines. The observations reveal several transient features, including poleward and equatorward steps in the observed boundaries, "braiding" of the backscatter power, and 2 minute quasi-periodic enhancements of the plasma drift and optical intensity, predominantly on closed field lines.

    Key words. Ionosphere (auroral ionosphere; plasma convection · Magnetospheric physics (magnetopause · cusp · and boundary layers

  14. Implications of Bandura's Observational Learning Theory for a Competency Based Teacher Education Model.

    Science.gov (United States)

    Hartjen, Raymond H.

    Albert Bandura of Stanford University has proposed four component processes to his theory of observational learning: a) attention, b) retention, c) motor reproduction, and d) reinforcement and motivation. This study represents one phase of an effort to relate modeling and observational learning theory to teacher training. The problem of this study…

  15. Communicating Earth Observation (EO)-based landslide mapping capabilities to practitioners

    Science.gov (United States)

    Albrecht, Florian; Hölbling, Daniel; Eisank, Clemens; Weinke, Elisabeth; Vecchiotti, Filippo; Kociu, Arben

    2016-04-01

    Current remote sensing methods and the available Earth Observation (EO) data for landslide mapping already can support practitioners in their processes for gathering and for using landslide information. Information derived from EO data can support emergency services and authorities in rapid mapping after landslide-triggering events, in landslide monitoring and can serve as a relevant basis for hazard and risk mapping. These applications also concern owners, maintainers and insurers of infrastructure. Most often practitioners have a rough overview of the potential and limits of EO-based methods for landslide mapping. However, semi-automated image analysis techniques are still rarely used in practice. This limits the opportunity for user feedback, which would contribute to improve the methods for delivering fully adequate results in terms of accuracy, applicability and reliability. Moreover, practitioners miss information on the best way of integrating the methods in their daily processes. Practitioners require easy-to-grasp interfaces for testing new methods, which in turn would provide researchers with valuable user feedback. We introduce ongoing work towards an innovative web service which will allow for fast and efficient provision of EO-based landslide information products and that supports online processing. We investigate the applicability of various very high resolution (VHR), e.g. WorldView-2/3, Pleiades, and high resolution (HR), e.g. Landsat, Sentinel-2, optical EO data for semi-automated mapping based on object-based image analysis (OBIA). The methods, i.e. knowledge-based and statistical OBIA routines, are evaluated regarding their suitability for inclusion in a web service that is easy to use with the least amount of necessary training. The pre-operational web service will be implemented for selected study areas in the Alps (Austria, Italy), where weather-induced landslides have happened in the past. We will test the service on its usability together

  16. Study of connectivity in student teams by observation of their learning processes

    Science.gov (United States)

    Pacheco, Patricio H.; Correa, Rafael D.

    2016-05-01

    A registration procedure based data tracking classroom activities students formed into teams, which are immersed in basic learning processes, particularly physical sciences is presented. For the analysis of the data various mathematical tools to deliver results in numerical indicators linking their learning, performance, quality of relational nexus to transformation their emotions. The range of variables under observation and further study, which is influenced by the evolution of the emotions of the different teams of students, it also covers the traditional approach to information delivery from outside (teaching in lecture) or from inside each team (abilities of pupils) to instructional materials that enhance learning inquiry and persuasion.

  17. In operandi observation of dynamic annealing: A case study of boron in germanium nanowire devices

    Energy Technology Data Exchange (ETDEWEB)

    Koleśnik-Gray, Maria M.; Krstić, Vojislav, E-mail: vojislav.krstic@fau.de [Department of Physics, Chair for Applied Physics, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Staudtstr. 7, 91058 Erlangen (Germany); Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), and AMBER at CRANN, Trinity College Dublin, College Green, Dublin 2 (Ireland); School of Physics, Trinity College Dublin, College Green, Dublin 2 (Ireland); Sorger, Christian; Weber, Heiko B. [Department of Physics, Chair for Applied Physics, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Staudtstr. 7, 91058 Erlangen (Germany); Biswas, Subhajit; Holmes, Justin D. [Materials Chemistry and Analysis Group, Department of Chemistry, Tyndall Institute, University College Cork, Cork (Ireland); Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), and AMBER at CRANN, Trinity College Dublin, College Green, Dublin 2 (Ireland)

    2015-06-08

    We report on the implantation of boron in individual, electrically contacted germanium nanowires with varying diameter and present a technique that monitors the electrical properties of a single device during implantation of ions. This method gives improved access to study the dynamic annealing ability of the nanowire at room temperature promoted by its quasi-one-dimensional confinement. Based on electrical data, we find that the dopant activation efficiency is nontrivially diameter dependent. As the diameter decreases, a transition from a pronounced dynamic-annealing to a radiation-damage dominated regime is observed.

  18. In operandi observation of dynamic annealing: A case study of boron in germanium nanowire devices

    International Nuclear Information System (INIS)

    We report on the implantation of boron in individual, electrically contacted germanium nanowires with varying diameter and present a technique that monitors the electrical properties of a single device during implantation of ions. This method gives improved access to study the dynamic annealing ability of the nanowire at room temperature promoted by its quasi-one-dimensional confinement. Based on electrical data, we find that the dopant activation efficiency is nontrivially diameter dependent. As the diameter decreases, a transition from a pronounced dynamic-annealing to a radiation-damage dominated regime is observed

  19. Estimation of Ganymede's Topography, Rotation and Tidal Deformation - a Study of Synthetic Ganymede Laser Altimeter Observations

    Science.gov (United States)

    Steinke, T.; Stark, A.; Steinbrügge, G.; Hussmann, H.; Oberst, J.

    2015-10-01

    We implement an iterative least-squares inversion routine to study the estimation of several dynamic Ganymede rotation parameters by laser altimetry. Based on spherical harmonic expansions of the global topography we use simulated Ganymede Laser Al-timeter observations representing the synthetic topography of the satellite. Besides the static topography we determine the dynamical parameters, such as the rotation rate, the amplitudes of physical librations, the spin pole orientation, and the tidal deformation. This parameters may strengthen implications for a liquid ocean beneath Ganymede's icy shell and, in addition, constrain geodetic frame parameters essential for various space-borne experiments.

  20. Gyroscopic waves in the base of the solar corona: A model and possible observational manifestations

    Science.gov (United States)

    Pisanko, Y. V.; Tritakis, V. P.; Paliatsos, A. G.

    1997-01-01

    A linear model for gyroscopic waves in the base of the solar corona is proposed. The purpose was to point out possible observational manifestations of the phenomenon. According to the model, these waves move slowly around the sun along heliolatitude circles. The fact that the red line corona is fainter on the solar side facing the apex and north-south and east-west asymmetries of the red coronal emission line could be interpreted as a possible observational manifestation of the gyroscopic wave phenomenon in the coronal base.