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Sample records for adequately robust early

  1. An adequately robust early TNF-alpha response is a hallmark of survival following trauma/hemorrhage.

    Directory of Open Access Journals (Sweden)

    Rajaie Namas

    Full Text Available BACKGROUND: Trauma/hemorrhagic shock (T/HS results in cytokine-mediated acute inflammation that is generally considered detrimental. METHODOLOGY/PRINCIPAL FINDINGS: Paradoxically, plasma levels of the early inflammatory cytokine TNF-alpha (but not IL-6, IL-10, or NO(2 (-/NO(3 (- were significantly elevated within 6 h post-admission in 19 human trauma survivors vs. 4 non-survivors. Moreover, plasma TNF-alpha was inversely correlated with Marshall Score, an index of organ dysfunction, both in the 23 patients taken together and in the survivor cohort. Accordingly, we hypothesized that if an early, robust pro-inflammatory response were to be a marker of an appropriate response to injury, then individuals exhibiting such a response would be predisposed to survive. We tested this hypothesis in swine subjected to various experimental paradigms of T/HS. Twenty-three anesthetized pigs were subjected to T/HS (12 HS-only and 11 HS + Thoracotomy; mean arterial pressure of 30 mmHg for 45-90 min along with surgery-only controls. Plasma obtained at pre-surgery, baseline post-surgery, beginning of HS, and every 15 min thereafter until 75 min (in the HS only group or 90 min (in the HS + Thoracotomy group was assayed for TNF-alpha, IL-6, IL-10, and NO(2 (-/NO(3 (-. Mean post-surgery+/-HS TNF-alpha levels were significantly higher in the survivors vs. non-survivors, while non-survivors exhibited no measurable change in TNF-alpha levels over the same interval. CONCLUSIONS/SIGNIFICANCE: Contrary to the current dogma, survival in the setting of severe, acute T/HS appears to be associated with an immediate increase in serum TNF-alpha. It is currently unclear if this response was the cause of this protection, a marker of survival, or both. This abstract won a Young Investigator Travel Award at the SHOCK 2008 meeting in Cologne, Germany.

  2. Adaptive robust image registration approach based on adequately sampling polar transform and weighted angular projection function

    Science.gov (United States)

    Wei, Zhao; Tao, Feng; Jun, Wang

    2013-10-01

    An efficient, robust, and accurate approach is developed for image registration, which is especially suitable for large-scale change and arbitrary rotation. It is named the adequately sampling polar transform and weighted angular projection function (ASPT-WAPF). The proposed ASPT model overcomes the oversampling problem of conventional log-polar transform. Additionally, the WAPF presented as the feature descriptor is robust to the alteration in the fovea area of an image, and reduces the computational cost of the following registration process. The experimental results show two major advantages of the proposed method. First, it can register images with high accuracy even when the scale factor is up to 10 and the rotation angle is arbitrary. However, the maximum scaling estimated by the state-of-the-art algorithms is 6. Second, our algorithm is more robust to the size of the sampling region while not decreasing the accuracy of the registration.

  3. How Much and What Kind? Identifying an Adequate Technology Infrastructure for Early Childhood Education. Policy Brief

    Science.gov (United States)

    Daugherty, Lindsay; Dossani, Rafiq; Johnson, Erin-Elizabeth; Wright, Cameron

    2014-01-01

    To realize the potential benefits of technology use in early childhood education (ECE), and to ensure that technology can help to address the digital divide, providers, families of young children, and young children themselves must have access to an adequate technology infrastructure. The goals for technology use in ECE that a technology…

  4. Information about robustness, reliability and safety in early design phases

    DEFF Research Database (Denmark)

    Marini, Vinicius Kaster

    This thesis is motivated by the need for support in considerations of robustness, reliability and safety during early design phases. The thesis deals with the question of how to codify and communicate failures and hazards, and devises measures against these. Current methods to robustness, reliabi......This thesis is motivated by the need for support in considerations of robustness, reliability and safety during early design phases. The thesis deals with the question of how to codify and communicate failures and hazards, and devises measures against these. Current methods to robustness......, reliability and safety reviewed have shortcomings including the complexity of using them and dependence on expert input for mitigating uncertainty and ambiguity among solution alternatives. This research is carried out using case studies: a pilot case to assess information requirements from reliability...... methods, and an industrial case to assess how the use of information about robustness, reliability and safety as practised by current methods influences concept development. Current methods cannot be used in early design phases due to their dependence on detailed design information for the identification...

  5. [Implementation of the intestinal micro flora in the early stage and adequate immunity later on].

    Science.gov (United States)

    Langhendries, J-P; Maton, P; François, A; Marguglio, A; Marion, W; Smeets, S; Philippet, P

    2010-09-01

    The pre and postnatal development of human immunity are remarkably continuous. The feto-placental unit builds up to promote a climate of immune tolerance specifically driven in this way by the maternal immunity. The process of birth triggers the development of the infant's postnatal immunity, in first place through the bacterial colonisation of a sterile intestinal mucosa. The progressive immune response stabilisation at the sub-mucosa level during the first year of life will arise from the interface between the host and its microflora. It will take place progressively and will occur thanks to a variety of successive and complementary very complex immune mechanisms, under the influence of a rich and diversified intestinal microbiotia. Solid scientific arguments allow hypothesising that immune deviances later in life could be the consequence of an inadequate bacterial pressure on the intestinal mucosa at the early stage. A variety of epigenetic modifications taking place in this early stage could account for the deviant programming of later immunity. Each health care provider should acknowledge that some therapeutic and nutritional interventions during the first year of life may interfere with this complex immune development, giving rise to a risk of increasing immune deviancies later on.

  6. Robust Early Pregnancy Prediction of Later Preeclampsia Using Metabolomic Biomarkers.

    LENUS (Irish Health Repository)

    Kenny, Louise C

    2010-09-13

    Preeclampsia is a pregnancy-specific syndrome that causes substantial maternal and fetal morbidity and mortality. The etiology is incompletely understood, and there is no clinically useful screening test. Current metabolomic technologies have allowed the establishment of metabolic signatures of preeclampsia in early pregnancy. Here, a 2-phase discovery\\/validation metabolic profiling study was performed. In the discovery phase, a nested case-control study was designed, using samples obtained at 15±1 weeks\\' gestation from 60 women who subsequently developed preeclampsia and 60 controls taking part in the prospective Screening for Pregnancy Endpoints cohort study. Controls were proportionally population matched for age, ethnicity, and body mass index at booking. Plasma samples were analyzed using ultra performance liquid chromatography-mass spectrometry. A multivariate predictive model combining 14 metabolites gave an odds ratio for developing preeclampsia of 36 (95% CI: 12 to 108), with an area under the receiver operator characteristic curve of 0.94. These findings were then validated using an independent case-control study on plasma obtained at 15±1 weeks from 39 women who subsequently developed preeclampsia and 40 similarly matched controls from a participating center in a different country. The same 14 metabolites produced an odds ratio of 23 (95% CI: 7 to 73) with an area under receiver operator characteristic curve of 0.92. The finding of a consistent discriminatory metabolite signature in early pregnancy plasma preceding the onset of preeclampsia offers insight into disease pathogenesis and offers the tantalizing promise of a robust presymptomatic screening test.

  7. Robust early pregnancy prediction of later preeclampsia using metabolomic biomarkers.

    LENUS (Irish Health Repository)

    Kenny, Louise C

    2012-01-31

    Preeclampsia is a pregnancy-specific syndrome that causes substantial maternal and fetal morbidity and mortality. The etiology is incompletely understood, and there is no clinically useful screening test. Current metabolomic technologies have allowed the establishment of metabolic signatures of preeclampsia in early pregnancy. Here, a 2-phase discovery\\/validation metabolic profiling study was performed. In the discovery phase, a nested case-control study was designed, using samples obtained at 15+\\/-1 weeks\\' gestation from 60 women who subsequently developed preeclampsia and 60 controls taking part in the prospective Screening for Pregnancy Endpoints cohort study. Controls were proportionally population matched for age, ethnicity, and body mass index at booking. Plasma samples were analyzed using ultra performance liquid chromatography-mass spectrometry. A multivariate predictive model combining 14 metabolites gave an odds ratio for developing preeclampsia of 36 (95% CI: 12 to 108), with an area under the receiver operator characteristic curve of 0.94. These findings were then validated using an independent case-control study on plasma obtained at 15+\\/-1 weeks from 39 women who subsequently developed preeclampsia and 40 similarly matched controls from a participating center in a different country. The same 14 metabolites produced an odds ratio of 23 (95% CI: 7 to 73) with an area under receiver operator characteristic curve of 0.92. The finding of a consistent discriminatory metabolite signature in early pregnancy plasma preceding the onset of preeclampsia offers insight into disease pathogenesis and offers the tantalizing promise of a robust presymptomatic screening test.

  8. Multiple giant succular and fusiform right and left coronary artery aneurysms after early and adequate treatment of atypical kawasaki disease with unusual presentation.

    Directory of Open Access Journals (Sweden)

    Mostafa Behjati-Ardakani

    2014-06-01

    Full Text Available The major complication of Kawasaki disease is coronary artery dilatation and aneurysm. It occurs in approximately 15-25% of untreated children with Kawasaki Disease. Early diagnosis and treatment with Intravenous immune globulin (IVIG and aspirin (ASA can reduce the incidence of coronary artery abnormality to 2%-5%. We report one case of Atypical Kawasaki Disease with Multiple giant coronary artery aneurysms despite early adequate treatment with IVIG and ASA.

  9. Adequate but not supplemental folic acid combined with soy isoflavones during early life improves bone health at adulthood in male mice.

    Science.gov (United States)

    Kaludjerovic, Jovana; Ward, Wendy E

    2013-10-01

    Previous investigations from our laboratory have demonstrated that neonatal exposure to soy isoflavones (ISO) improves bone outcomes in CD-1 mice at adulthood with greater benefits in females than males. This study determined whether early-life exposure to supplemental folic acid (FA) - that may enhance DNA methylation of target genes - in combination with ISO provides greater benefits to male bone development than ISO alone. CD-1 dams were randomized to a low (0 mg/kg diet), adequate (2 mg/kg diet) or supplemental (8 mg/kg diet) level of FA during pregnancy and lactation. Offspring received corn oil or ISO (7 mg/kg of body weight per day) from postnatal day 1-10. From weaning, males were fed adequate FA and studied to age 4 months. Offspring exposed to adequate FA+ISO had multiple benefits to bone health: higher (Pbenefits to male bone development, while improvements induced by supplemental FA+ISO were limited to a higher level of serum OPG. Mechanistic studies are needed to better understand how FA and ISO improve bone development in male offspring.

  10. Validation of three early ejaculation diagnostic tools: a composite measure is accurate and more adequate for diagnosis by updated diagnostic criteria.

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    Patrick Jern

    Full Text Available PURPOSE: To validate three early ejaculation diagnostic tools, and propose a new tool for diagnosis in line with proposed changes to diagnostic criteria. Significant changes to diagnostic criteria are expected in the near future. Available screening tools do not necessarily reflect proposed changes. MATERIALS AND METHODS: Data from 148 diagnosed early ejaculation patients (M age = 42.8 and 892 controls (M age = 33.1 years from a population-based sample were used. Participants responded to three different questionnaires (Premature Ejaculation Profile; Premature Ejaculation Diagnostic Tool; Multiple Indicators of Premature Ejaculation. Stopwatch measured ejaculation latency times were collected from a subsample of early ejaculation patients. We used two types of responses to the questionnaires depending on the treatment status of the patients 1 responses regarding the situation before starting pharmacological treatment and 2 responses regarding current situation. Logistic regressions and Receiver Operating Characteristics were used to assess ability of both the instruments and individual items to differentiate between patients and controls. RESULTS: All instruments had very good precision (Areas under the Curve ranging from .93-.98. A new five-item instrument (named CHecklist for Early Ejaculation Symptoms - CHEES consisting of high-performance variables selected from the three instruments had validity (Nagelkerke R (2 range .51-.79 for backwards/forwards logistic regression equal to or slightly better than any individual instrument (i.e., had slightly higher validity statistics, but these differences did not achieve statistical significance. Importantly, however, this instrument was more in line with proposed changes to diagnostic criteria. CONCLUSIONS: All three screening tools had good validity. A new 5-item diagnostic tool (CHEES based on the three instruments had equal or somewhat more favorable validity statistics compared to the other three

  11. Can Targeted Intervention Mitigate Early Emotional and Behavioral Problems?: Generating Robust Evidence within Randomized Controlled Trials.

    Directory of Open Access Journals (Sweden)

    Orla Doyle

    Full Text Available This study examined the impact of a targeted Irish early intervention program on children's emotional and behavioral development using multiple methods to test the robustness of the results. Data on 164 Preparing for Life participants who were randomly assigned into an intervention group, involving home visits from pregnancy onwards, or a control group, was used to test the impact of the intervention on Child Behavior Checklist scores at 24-months. Using inverse probability weighting to account for differential attrition, permutation testing to address small sample size, and quantile regression to characterize the distributional impact of the intervention, we found that the few treatment effects were largely concentrated among boys most at risk of developing emotional and behavioral problems. The average treatment effect identified a 13% reduction in the likelihood of falling into the borderline clinical threshold for Total Problems. The interaction and subgroup analysis found that this main effect was driven by boys. The distributional analysis identified a 10-point reduction in the Externalizing Problems score for boys at the 90th percentile. No effects were observed for girls or for the continuous measures of Total, Internalizing, and Externalizing problems. These findings suggest that the impact of this prenatally commencing home visiting program may be limited to boys experiencing the most difficulties. Further adoption of the statistical methods applied here may help to improve the internal validity of randomized controlled trials and contribute to the field of evaluation science more generally.ISRCTN Registry ISRCTN04631728.

  12. Early-onset and robust amyloid pathology in a new homozygous mouse model of Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Antje Willuweit

    Full Text Available BACKGROUND: Transgenic mice expressing mutated amyloid precursor protein (APP and presenilin (PS-1 or -2 have been successfully used to model cerebral beta-amyloidosis, one of the characteristic hallmarks of Alzheimer's disease (AD pathology. However, the use of many transgenic lines is limited by premature death, low breeding efficiencies and late onset and high inter-animal variability of the pathology, creating a need for improved animal models. Here we describe the detailed characterization of a new homozygous double-transgenic mouse line that addresses most of these issues. METHODOLOGY/PRINCIPAL FINDINGS: The transgenic mouse line (ARTE10 was generated by co-integration of two transgenes carrying the K670N/M671L mutated amyloid precursor protein (APP(swe and the M146V mutated presenilin 1 (PS1 both under control of a neuron-specific promoter. Mice, hemi- as well as homozygous for both transgenes, are viable and fertile with good breeding capabilities and a low rate of premature death. They develop robust AD-like cerebral beta-amyloid plaque pathology with glial inflammation, signs of neuritic dystrophy and cerebral amyloid angiopathy. Using our novel image analysis algorithm for semi-automatic quantification of plaque burden, we demonstrate an early onset and progressive plaque deposition starting at 3 months of age in homozygous mice with low inter-animal variability and 100%-penetrance of the phenotype. The plaques are readily detected in vivo by PiB, the standard human PET tracer for AD. In addition, ARTE10 mice display early loss of synaptic markers and age-related cognitive deficits. By applying a gamma-secretase inhibitor we show a dose dependent reduction of soluble amyloid beta levels in the brain. CONCLUSIONS: ARTE10 mice develop a cerebral beta-amyloidosis closely resembling the beta-amyloid-related aspects of human AD neuropathology. Unifying several advantages of previous transgenic models, this line particularly qualifies for

  13. Early life DNA vaccination with the H gene of Canine distemper virus induces robust protection against distemper

    DEFF Research Database (Denmark)

    Jensen, Trine Hammer; Nielsen, Line; Aasted, Bent;

    2009-01-01

    Young mink kits (n = 8)were vaccinated withDNA plasmids encoding the viral haemagglutinin protein (H) of a vaccine strain of Canine distemper virus (CDV). Virus neutralising (VN) antibodieswere induced after 2 immunisations and after the third immunisation all kits had high VN antibody titres...... demonstrate that early life DNA vaccination with the H gene of a CDV vaccine strain induced robust protective immunity against a recent wild type CDV....

  14. Split Quasi-adequate Semigroups

    Institute of Scientific and Technical Information of China (English)

    Xiao Jiang GUO; Ting Ting PENG

    2012-01-01

    The so-called split IC quasi-adequate semigroups are in the class of idempotent-connected quasi-adequate semigroups.It is proved that an IC quasi-adequate semigroup is split if and only if it has an adequate transversal.The structure of such semigroup whose band of idempotents is regular will be particularly investigated.Our obtained results enrich those results given by McAlister and Blyth on split orthodox semigroups.

  15. On the validity and robustness of the scale error phenomenon in early childhood.

    Science.gov (United States)

    DeLoache, Judy S; LoBue, Vanessa; Vanderborght, Mieke; Chiong, Cynthia

    2013-02-01

    Scale errors is a term referring to very young children's serious efforts to perform actions on miniature replica objects that are impossible due to great differences in the size of the child's body and the size of the target objects. We report three studies providing further documentation of scale errors and investigating the validity and robustness of the phenomenon. In the first, we establish that 2-year-olds' behavior in response to prompts to "pretend" with miniature replica objects differs dramatically from scale errors. The second and third studies address the robustness of the phenomenon and its relative imperviousness to attempts to influence the rate of scale errors.

  16. Robust and flexible mapping for real-time distributed applications during the early design phases

    DEFF Research Database (Denmark)

    Gan, Junhe; Pop, Paul; Gruian, Flavius

    2012-01-01

    We are interested in mapping hard real-time applications on distributed heterogeneous architectures. An application is modeled as a set of tasks, and we consider a fixed-priority preemptive scheduling policy. We target the early design phases, when decisions have a high impact on the subsequent...... implementation choices. However, due to a lack of information, the early design phases are characterized by uncertainties, e.g., in the worst-case execution times (wcets), or in the functionality requirements. We model uncertainties in the wcets using the “percentile method”. The uncertainties...... of taking into account the uncertainties during the early design phases....

  17. Hyperbolic semi-adequate links

    OpenAIRE

    Futer, David; Kalfagianni, Efstratia; Purcell, Jessica S.

    2013-01-01

    We provide a diagrammatic criterion for semi-adequate links to be hyperbolic. We also give a conjectural description of the satellite structures of semi-adequate links. One application of our result is that the closures of sufficiently complicated positive braids are hyperbolic links.

  18. Parental death and bipolar disorder: a robust association was found in early maternal suicide

    DEFF Research Database (Denmark)

    Tsuchiya, Kenji; Agerbo, Esben; Mortensen, Preben Bo

    2005-01-01

    aimed to explore whether suicide as well as the non-suicidal death of father, mother, or siblings are associated with an increased risk for bipolar disorder, and whether the possible association is modified by the age at which the subject experiences such a death in the family. METHODS: The subjects...... followed until, but not exceeding, the age of 38. CONCLUSION: Early parental, particularly maternal, suicide increases the risk for bipolar disorder in the offspring. Possible explanations include a family history of mental disorders as well as psychosocial factors.......BACKGROUND: Previous studies have suggested that early parental death may be associated with the emergence of bipolar disorder in later life. However, it remains unknown whether this association applies specifically to parental death due to suicide or only to early parental death. The present study...

  19. Which System Variables Carry Robust Early Signs of Upcoming Phase Transition? An Ecological Example.

    Science.gov (United States)

    Negahbani, Ehsan; Steyn-Ross, D Alistair; Steyn-Ross, Moira L; Aguirre, Luis A

    2016-01-01

    Growth of critical fluctuations prior to catastrophic state transition is generally regarded as a universal phenomenon, providing a valuable early warning signal in dynamical systems. Using an ecological fisheries model of three populations (juvenile prey J, adult prey A and predator P), a recent study has reported silent early warning signals obtained from P and A populations prior to saddle-node (SN) bifurcation, and thus concluded that early warning signals are not universal. By performing a full eigenvalue analysis of the same system we demonstrate that while J and P populations undergo SN bifurcation, A does not jump to a new state, so it is not expected to carry early warning signs. In contrast with the previous study, we capture a significant increase in the noise-induced fluctuations in the P population, but only on close approach to the bifurcation point; it is not clear why the P variance initially shows a decaying trend. Here we resolve this puzzle using observability measures from control theory. By computing the observability coefficient for the system from the recordings of each population considered one at a time, we are able to quantify their ability to describe changing internal dynamics. We demonstrate that precursor fluctuations are best observed using only the J variable, and also P variable if close to transition. Using observability analysis we are able to describe why a poorly observable variable (P) has poor forecasting capabilities although a full eigenvalue analysis shows that this variable undergoes a bifurcation. We conclude that observability analysis provides complementary information to identify the variables carrying early-warning signs about impending state transition.

  20. Which System Variables Carry Robust Early Signs of Upcoming Phase Transition? An Ecological Example

    Science.gov (United States)

    Negahbani, Ehsan; Steyn-Ross, D. Alistair; Steyn-Ross, Moira L.; Aguirre, Luis A.

    2016-01-01

    Growth of critical fluctuations prior to catastrophic state transition is generally regarded as a universal phenomenon, providing a valuable early warning signal in dynamical systems. Using an ecological fisheries model of three populations (juvenile prey J, adult prey A and predator P), a recent study has reported silent early warning signals obtained from P and A populations prior to saddle-node (SN) bifurcation, and thus concluded that early warning signals are not universal. By performing a full eigenvalue analysis of the same system we demonstrate that while J and P populations undergo SN bifurcation, A does not jump to a new state, so it is not expected to carry early warning signs. In contrast with the previous study, we capture a significant increase in the noise-induced fluctuations in the P population, but only on close approach to the bifurcation point; it is not clear why the P variance initially shows a decaying trend. Here we resolve this puzzle using observability measures from control theory. By computing the observability coefficient for the system from the recordings of each population considered one at a time, we are able to quantify their ability to describe changing internal dynamics. We demonstrate that precursor fluctuations are best observed using only the J variable, and also P variable if close to transition. Using observability analysis we are able to describe why a poorly observable variable (P) has poor forecasting capabilities although a full eigenvalue analysis shows that this variable undergoes a bifurcation. We conclude that observability analysis provides complementary information to identify the variables carrying early-warning signs about impending state transition. PMID:27631984

  1. A robust prognostic gene expression signature for early stage lung adenocarcinoma

    DEFF Research Database (Denmark)

    Krzystanek, Marcin; Moldvay, Judit; Szüts, David;

    2016-01-01

    Stage I lung adenocarcinoma is usually not treated with adjuvant chemotherapy; however, around half of these patients do not survive 5 years. Therefore, a reliable prognostic biomarker for early stage patients would be critical to identify those most likely to benefit from early additional treatm...... not given adjuvant therapy. Seven genes consistently obtained statistical significance in Cox regression for overall survival. The combined signature has a weighted mean hazard ratio of 3.2 in all cohorts and 3.0 (C.I. 1.3-7.4, p ...... treatments. Several studies have searched for gene expression prognostic biomarkers for lung adenocarcinoma, but these have not yielded a widely accepted prognosticator. We analyzed gene expression from seven published lung adenocarcinoma cohorts for which we included only stage I and II patients who were...

  2. Robust PCA and MIC statistics of baryons in early mini-haloes

    CERN Document Server

    de Souza, R S; Biffi, V; Ciardi, B

    2013-01-01

    We present a novel approach, based on robust principal components analysis (RPCA) and maximal information coefficient (MIC), to study the redshift dependence of halo baryonic properties. Our data is composed by a set of different physical quantities for primordial mini-haloes: dark-matter mass ($M_{\\mathrm{dm}}$), gas mass ($M_{\\mathrm{gas}}$), stellar mass, molecular fraction (${\\mathrm{x_{mol}}}$), metallicity (\\textit{Z}), star formation rate (\\textit{SFR}) and temperature. We find that $M_{\\mathrm{dm}}$ and $M_{\\mathrm{gas}}$ are dominant factors for variance at high redshift. Nonetheless, with the emergence of the first stars and subsequent feedback mechanisms, ${\\mathrm{x_{mol}}}$, \\textit{SFR} and \\textit{Z} start to dominate the variance. The RPCA gives three principal components (PCs) that are capable to explain more than 97 per cent of the data variance at any redshift, while 2 PCs usually account for more than 92 per cent. Our MIC analysis suggests that all the gaseous properties have a stronger co...

  3. Gene Expression Noise Enhances Robust Organization of the Early Mammalian Blastocyst

    Science.gov (United States)

    Wang, Qixuan; Du, Huijing; Peng, Tao; Chiang, Michael; Cinquin, Olivier; Cho, Ken

    2017-01-01

    A critical event in mammalian embryo development is construction of an inner cell mass surrounded by a trophoectoderm (a shell of cells that later form extraembryonic structures). We utilize multi-scale, stochastic modeling to investigate the design principles responsible for robust establishment of these structures. This investigation makes three predictions, each supported by our quantitative imaging. First, stochasticity in the expression of critical genes promotes cell plasticity and has a critical role in accurately organizing the developing mouse blastocyst. Second, asymmetry in the levels of noise variation (expression fluctuation) of Cdx2 and Oct4 provides a means to gain the benefits of noise-mediated plasticity while ameliorating the potentially detrimental effects of stochasticity. Finally, by controlling the timing and pace of cell fate specification, the embryo temporally modulates plasticity and creates a time window during which each cell can continually read its environment and adjusts its fate. These results suggest noise has a crucial role in maintaining cellular plasticity and organizing the blastocyst. PMID:28114387

  4. Mast cell activation and neutrophil recruitment promotes early and robust inflammation in the meninges in EAE.

    Science.gov (United States)

    Christy, Alison L; Walker, Margaret E; Hessner, Martin J; Brown, Melissa A

    2013-05-01

    The meninges are often considered inert tissues that house the CSF and provide protection for the brain and spinal cord. Yet emerging data demonstrates that they are also active sites of immune responses. Furthermore, the blood-CSF barrier surrounding meningeal blood vessels, together with the blood-brain barrier (BBB), is postulated to serve as a gateway for the pathological infiltration of immune cells into the CNS in multiple sclerosis (MS). Our previous studies using mast cell-deficient (Kit(W/Wv)) mice demonstrated that mast cells resident in the dura mater and pia mater exacerbate experimental autoimmune encephalomyelitis (EAE), a rodent model of MS, by facilitating CNS inflammatory cell influx. Here we examined the underlying mechanisms that mediate these effects. We demonstrate that there are dramatic alterations in immune associated gene expression in the meninges in pre-clinical disease, including those associated with mast cell and neutrophil function. Meningeal mast cells are activated within 24 h of disease induction, but do not directly compromise CNS vascular integrity. Rather, through production of TNF, mast cells elicit an early influx of neutrophils, cells known to alter vascular permeability, into the meninges. These data add to the growing evidence that inflammation in the meninges precedes CNS immune cell infiltration and establish that mast cells are among the earliest participants in these disease-initiating events. We hypothesize that mast cell-dependent neutrophil recruitment and activation in the meninges promotes early breakdown of the local BBB and CSF-blood barrier allowing initial immune cell access to the CNS.

  5. 21 CFR 1404.900 - Adequate evidence.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Adequate evidence. 1404.900 Section 1404.900 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 1404.900 Adequate evidence. Adequate evidence means information sufficient...

  6. Abundant Semigroups with a Multiplicative Adequate Transversal

    Institute of Scientific and Technical Information of China (English)

    GUO Xiao Jiang

    2002-01-01

    The aim of this paper is to investigate abundant semigroups with a multiplicative adequate transversal. Some properties and characterizations for such semigroups are obtained. In particular,we establish the structure of this class of abundant semigroups in terms of left normal bands, right normal bands and adequate semigroups with some simple compatibility conditions. Finally, we apply this structure to some special cases.

  7. Repeatability of metabolic responses to a nutrient deficiency in early and mid lactation and implications for robustness of dairy cows.

    Science.gov (United States)

    Gross, J J; Bruckmaier, R M

    2015-12-01

    Nutrient partitioning toward the mammary gland during insufficient energy and nutrient supply is a strategy to ensure survival of the offspring in mammalian species. This homeorhetic priority of the mammary gland is also present in the modern dairy cow, in particular in early lactation. However, despite similar metabolic loads, the adaptive response to a given metabolic load varies considerably among animals. The aim of this study was to investigate if individual cows respond in a consistent manner to a negative energy balance (NEB) in early and mid lactation. Twenty-five dairy cows experienced the usual NEB after parturition and were subjected to a second 3-wk NEB induced by feed restriction in mid lactation. Animals were retrospectively ranked according to their highest plasma nonesterified fatty acid (NEFA) concentration in wk 1 to 4 postpartum. The animals with the 33% highest and 33% lowest values were selected and classified either as the high response (HR) or low response (LR) group. Before parturition, no differences in the studied parameters, dry matter intake, energy balance, concentrations of glucose, NEFA, β-hydroxybutyrate, cholesterol, triglycerides, growth hormone, and insulin-like growth factor-1, were detected between LR and HR. After parturition, milk yield and energy-corrected milk yield was higher for HR compared with LR in wk 2 to 14 and wk 1 to 6, respectively. During feed restriction in wk 15 to 17 postpartum, no differences in energy-corrected milk between LR and HR were found. Energy balance was more negative in HR during the NEB in early lactation, but not different from LR during feed restriction in mid lactation. Although plasma concentrations of glucose, growth hormone, triglycerides, and cholesterol showed group differences in early lactation, but not during feed restriction, the plasma concentrations of NEFA, β-hydroxybutyrate, and insulin-like growth factor-1 in HR changed repeatedly to a greater extent during the NEB at the 2

  8. Simple and robust diagnosis of early, small and AFP-negative primary hepatic carcinomas: an integrative approach of serum fluorescence and conventional blood tests.

    Science.gov (United States)

    Wang, Ting; Zhang, Kun-He; Hu, Piao-Ping; Huang, Zeng-Yong; Zhang, Pan; Wan, Qin-Si; Huang, De-Qiang; Lv, Nong-Hua

    2016-09-27

    The diagnosis of early, small and alpha-fetoprotein (AFP)-negative primary hepatic carcinomas (PHCs) remains a significant challenge. We developed a simple and robust approach to noninvasively detect these PHCs. A rapid, high-throughput and single-tube method was firstly developed to measure serum autofluorescence and cell-free DNA (cfDNA)-related fluorescence using a real-time PCR system, and both types of serum fluorescence were measured and routine laboratory data were collected in 1229 subjects, including 353 PHC patients, 331 liver cirrhosis (LC) patients, 213 chronic hepatitis (CH) patients and 332 normal controls (NC). The results showed that fluorescence indicators of PHC differed from those of NC, CH and LC to various extents, and all of them were not associated with age, gender, or AFP level. The logistic regression models established with the fluorescence indicators alone and combined with AFP, hepatic function tests and blood cell analyses were valuable for distinguishing early, small, AFP-negative and all PHC from LC, CH, NC and all non-PHC, with areas under the receiver operating characteristic curves 0.857-0.993 and diagnostic accuracies 80.2-97.7%. Conclusively, serum autofluorescence and cfDNA-related fluorescence are able to be rapidly and simultaneously measured by our simple method and valuable for diagnosing early, small and AFP-negative PHCs, especially integrating with AFP and conventional blood tests.

  9. Extended longevity and robust early-stage development of Caenorhabditis elegans by a soil microbe, Lysinibacillus sphaericus.

    Science.gov (United States)

    Go, Junhyeok; Lee, Kang-Mu; Park, Yongjin; Yoon, Sang Sun

    2014-12-01

    Caenorhabditis elegans, originally isolated from soil, is a nematode used in various fields of biological research including host–microbe interaction. While bacterial pathogens responsible for human infections have been actively studied in C. elegans, very few bacterial species that provide beneficial effects on C. elegans have been reported. Here, we tested several bacterial soil isolates and then characterized the effects of Lysinibacillus sphaericus on C. elegans growth-related phenotypes. Worms fed with L. sphaericus lived significantly longer than those growing with typical Escherichia coli OP50. Early- and juvenile-stage growth was also highly stimulated by L. sphaericus; body size at 28 h post-hatching was > 2 times larger than OP50-fed worms and L. sphaericus-fed worms moved through the larval stage development more rapidly than control worms. In addition, significantly elevated fertilization was observed in worms fed with L. sphaericus (∼ 8 h faster than the control group). Furthermore, growth with L. sphaericus resulted in the production of larger numbers of progeny than the control growth with OP50. Worms grown with L. sphaericus were highly resistant to oxidative, osmotic and infection stresses. Together, our results reveal a novel mode of growth that involves healthy ageing of nematodes.

  10. The efficacy of support vector machines (SVM) in robust determination of earthquake early warning magnitudes in central Japan

    Indian Academy of Sciences (India)

    Ramakrushna Reddy; Rajesh R Nair

    2013-10-01

    This work deals with a methodology applied to seismic early warning systems which are designed to provide real-time estimation of the magnitude of an event. We will reappraise the work of Simons et al. (2006), who on the basis of wavelet approach predicted a magnitude error of ±1. We will verify and improve upon the methodology of Simons et al. (2006) by applying an SVM statistical learning machine on the time-scale wavelet decomposition methods. We used the data of 108 events in central Japan with magnitude ranging from 3 to 7.4 recorded at KiK-net network stations, for a source–receiver distance of up to 150 km during the period 1998–2011. We applied a wavelet transform on the seismogram data and calculating scale-dependent threshold wavelet coefficients. These coefficients were then classified into low magnitude and high magnitude events by constructing a maximum margin hyperplane between the two classes, which forms the essence of SVMs. Further, the classified events from both the classes were picked up and linear regressions were plotted to determine the relationship between wavelet coefficient magnitude and earthquake magnitude, which in turn helped us to estimate the earthquake magnitude of an event given its threshold wavelet coefficient. At wavelet scale number 7, we predicted the earthquake magnitude of an event within 2.7 seconds. This means that a magnitude determination is available within 2.7 s after the initial onset of the P-wave. These results shed light on the application of SVM as a way to choose the optimal regression function to estimate the magnitude from a few seconds of an incoming seismogram. This would improve the approaches from Simons et al. (2006) which use an average of the two regression functions to estimate the magnitude.

  11. Real Time Investments with Adequate Portfolio Theory

    Directory of Open Access Journals (Sweden)

    Alina Kvietkauskienė

    2015-02-01

    Full Text Available The objective of this paper is to identify investment decision makingschemes using the adequate portfolio model. This approach can be employed to project investment in stocks, using the opportunities offered by the markets and investor intelligence. It was decided to use adequate portfolio theory for investment decision making, simulation of financial markets, and optimisation of utility function. The main conclusion of article suggests investigating return on individual portfolio level. Real investment is a way to make sure of the soundness of applicable strategies.

  12. Defining an Adequate Education for English Learners

    OpenAIRE

    Patricia Gándara; Russell W. Rumberger

    2008-01-01

    This article explores the components of an “adequate” education for linguistic minority students in California and attempts to distinguish these from the components of an adequate education for low-income students who are native English speakers. About 1.6 million students were classified as English learners (ELs) in California in 2006. We argue that in order to determine the costs of educating these students, it is necessary to specify the goals of instruction. Four possible goals are: (1) r...

  13. Robust Scientists

    DEFF Research Database (Denmark)

    Gorm Hansen, Birgitte

    as the analytical framework for describing the complex relationship between academic science and its so called “external” habitat. Although relational skills and adaptability do seem to be at the heart of successful research management, the key to success does not lie with the ability to assimilate to industrial...... knowledge", Danish research policy seems to have helped develop politically and economically "robust scientists". Scientific robustness is acquired by way of three strategies: 1) tasting and discriminating between resources so as to avoid funding that erodes academic profiles and push scientists away from...... and industrial interests. The paper concludes by stressing the potential danger of policy habitats who have promoted the evolution of robust scientists based on a competitive system where only the fittest survive. Robust scientists, it is argued, have the potential to become a new “invasive species...

  14. Robust Scientists

    DEFF Research Database (Denmark)

    Gorm Hansen, Birgitte

    2012-01-01

    as the analytical framework for descri bing the complex relationship between academic science and its so called “external” habitat. Although relational skills and adaptability do seem to be at the heart of successful research management, the key to success does not lie with the ability to assimilate to industrial...... knowledge", Danish research policy seems to have helped develop politically and economically "robust scientists". Scientific robustness is acquired by way of three strategies: 1) tasting and discriminating between resources so as to avoid funding that erodes academic profiles and push scientists away from...... and industrial intere sts. The paper concludes by stressing the potential danger of policy habitats who have promoted the evolution of robust scientists based on a competitive system where only the fittest survive. Robust scientists, it is argued, have the potential to become a new “invasive species...

  15. Early

    Directory of Open Access Journals (Sweden)

    Kamel Abd Elaziz Mohamed

    2014-04-01

    Conclusion: Early PDT is recommended for patients who require prolonged tracheal intubation in the ICU as outcomes like the duration of mechanical ventilation length of ICU stay and hospital stay were significantly shorter in early tracheostomy.

  16. Is a vegetarian diet adequate for children.

    Science.gov (United States)

    Hackett, A; Nathan, I; Burgess, L

    1998-01-01

    The number of people who avoid eating meat is growing, especially among young people. Benefits to health from a vegetarian diet have been reported in adults but it is not clear to what extent these benefits are due to diet or to other aspects of lifestyles. In children concern has been expressed concerning the adequacy of vegetarian diets especially with regard to growth. The risks/benefits seem to be related to the degree of restriction of he diet; anaemia is probably both the main and the most serious risk but this also applies to omnivores. Vegan diets are more likely to be associated with malnutrition, especially if the diets are the result of authoritarian dogma. Overall, lacto-ovo-vegetarian children consume diets closer to recommendations than omnivores and their pre-pubertal growth is at least as good. The simplest strategy when becoming vegetarian may involve reliance on vegetarian convenience foods which are not necessarily superior in nutritional composition. The vegetarian sector of the food industry could do more to produce foods closer to recommendations. Vegetarian diets can be, but are not necessarily, adequate for children, providing vigilance is maintained, particularly to ensure variety. Identical comments apply to omnivorous diets. Three threats to the diet of children are too much reliance on convenience foods, lack of variety and lack of exercise.

  17. Robust Chaos

    CERN Document Server

    Banerjee, S; Grebogi, C; Banerjee, Soumitro; Yorke, James A.; Grebogi, Celso

    1998-01-01

    It has been proposed to make practical use of chaos in communication, in enhancing mixing in chemical processes and in spreading the spectrum of switch-mode power suppies to avoid electromagnetic interference. It is however known that for most smooth chaotic systems, there is a dense set of periodic windows for any range of parameter values. Therefore in practical systems working in chaotic mode, slight inadvertent fluctuation of a parameter may take the system out of chaos. We say a chaotic attractor is robust if, for its parameter values there exists a neighborhood in the parameter space with no periodic attractor and the chaotic attractor is unique in that neighborhood. In this paper we show that robust chaos can occur in piecewise smooth systems and obtain the conditions of its occurrence. We illustrate this phenomenon with a practical example from electrical engineering.

  18. Robust Econometrics

    OpenAIRE

    Čίžek, Pavel; Härdle, Wolfgang Karl

    2006-01-01

    Econometrics often deals with data under, from the statistical point of view, non-standard conditions such as heteroscedasticity or measurement errors and the estimation methods need thus be either adopted to such conditions or be at least insensitive to them. The methods insensitive to violation of certain assumptions, for example insensitive to the presence of heteroscedasticity, are in a broad sense referred to as robust (e.g., to heteroscedasticity). On the other hand, there is also a mor...

  19. Adequate Screening of Youngsters for Depressive Characteristics

    Directory of Open Access Journals (Sweden)

    Lotte Theuwis

    2013-06-01

    Full Text Available In order to set up an effective early-detection of depressive symptoms in youngsters, the current study aims to investigate whether two measure moments of the Children's Depression Inventory (CDI improve screening and whether a multi-informant procedure is superior compared to a single-informant procedure thereby controlling for comorbid symptoms. Method.Youngsters (10-15 years filled in the CDI and an Anxiety Scale at Time 1 and the CDI and Youth Self Report one week later. Next, a structured clinical interview was administered. The Child Behaviour CheckList was filled in by the parents. Results. Two measure moments of the CDI are not more accurate in capturing disordered mood changes. Furthermore, parent reports were no significant contributor to the variance over and above the CDI. Discussion. A second moment does not increase screening accuracy. Further research on setting up an effective multistage screening procedure for depressive symptoms for youngsters is however necessary.

  20. Robust factorization

    DEFF Research Database (Denmark)

    Aanæs, Henrik; Fisker, Rune; Åström, Kalle;

    2002-01-01

    Factorization algorithms for recovering structure and motion from an image stream have many advantages, but they usually require a set of well-tracked features. Such a set is in generally not available in practical applications. There is thus a need for making factorization algorithms deal...... effectively with errors in the tracked features. We propose a new and computationally efficient algorithm for applying an arbitrary error function in the factorization scheme. This algorithm enables the use of robust statistical techniques and arbitrary noise models for the individual features....... These techniques and models enable the factorization scheme to deal effectively with mismatched features, missing features, and noise on the individual features. The proposed approach further includes a new method for Euclidean reconstruction that significantly improves convergence of the factorization algorithms...

  1. Abundant Semigroups Which Are Disjoint Unions of Multiplicative Adequate Transversals

    Institute of Scientific and Technical Information of China (English)

    Haijun LIU; Xiaojiang GUO

    2013-01-01

    The aim of this paper is to study abundant semigroups which are disjoint unions of multiplicative adequate tranversals.After obtaining some properties of such semigroup,we prove that a semigroup is a disjoint union of multiplicative adequate transversals if and only if it is isomorphic to the direct product of a rectangular band and an adequate semigroup.

  2. A Class of Left E-adequate Semigroups

    Institute of Scientific and Technical Information of China (English)

    LI YONG-HUA; HE YONG

    2010-01-01

    In this paper we establish a construction of a class of left E-adequate semigroups by using semilattices of cancellative monoids and fundamental left E-adequate semigroups. We first introduce concepts of type μ+ (μ*, μ) abundant semigroups and type μ+ left E-adequate semigroups. In fact, regular semigroups are type μ+ abundant semigroups and inverse semigroups are type μ+ left E-adequate semigroups. Next, we construct a special kind of algebras called E+-product. It is proved that every E+-product is a type μ+ left E-adequate semigroup, and every type μ+ left E-adequate semigroup is isomorphic to an E+-product of a semilattice of cancellative monoids with a fundamental left E-adequate semigroup. Finally, as a corollary of the main result, it is deduced that every inverse semigroup is isomorphic to an E+-product of a Clifford semigroup by a fundamental inverse semigroup.

  3. ‘Do larger molars and robust jaws in early hominins represent dietary adaptation?’ A New Study in Tooth Wear

    Directory of Open Access Journals (Sweden)

    Anna Frances Clement

    2013-10-01

    Full Text Available Diet imposes significant constraints on the biology and behaviour of animals. The fossil record suggests that key changes in diet have taken place throughout the course of human evolution. Defining these changes enables us to understand the behaviour of our extinct fossil ancestors. Several lines of evidence are available for studying the diet of early hominins, including craniodental morphology, palaeoecology, dental microwear and stable isotopes. They do, however, often provide conflicting results. Using dental macrowear analysis, this new UCL Institute of Archaeology project will provide an alternative source of information on early hominin diet. Dental macrowear has often been used to analyse diet in archaeological populations, but this will be the first time that this type of detailed study has been applied to the early hominin fossil record.

  4. 13 CFR 108.200 - Adequate capital for NMVC Companies.

    Science.gov (United States)

    2010-01-01

    ... VENTURE CAPITAL (âNMVCâ) PROGRAM Qualifications for the NMVC Program Capitalizing A Nmvc Company § 108.200 Adequate capital for NMVC Companies. You must meet the requirements of §§ 108.200-108.230 in order to... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Adequate capital for...

  5. 40 CFR 716.25 - Adequate file search.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Adequate file search. 716.25 Section... ACT HEALTH AND SAFETY DATA REPORTING General Provisions § 716.25 Adequate file search. The scope of a person's responsibility to search records is limited to records in the location(s) where the...

  6. 9 CFR 305.3 - Sanitation and adequate facilities.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Sanitation and adequate facilities. 305.3 Section 305.3 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... OF VIOLATION § 305.3 Sanitation and adequate facilities. Inspection shall not be inaugurated if...

  7. 10 CFR 503.35 - Inability to obtain adequate capital.

    Science.gov (United States)

    2010-01-01

    ... capital investment, through tariffs, without unreasonably adverse economic effect on its service area... 10 Energy 4 2010-01-01 2010-01-01 false Inability to obtain adequate capital. 503.35 Section 503... New Facilities § 503.35 Inability to obtain adequate capital. (a) Eligibility. Section 212(a)(1)(D)...

  8. Robust control investigations for equipment loaded panels

    DEFF Research Database (Denmark)

    Aglietti, G.S.; Langley, R.S.; Rogers, E.;

    1998-01-01

    This paper develops a modelling technique for equipment load panels which directly produces (adequate) models of the underlying dynamics on which to base robust controller design/evaluations. This technique is based on the use of the Lagrange's equations of motion and the resulting models are ver...... are verified against those produced by a finite Element Method Model...

  9. Non-clinical studies required for new drug development - Part I: early in silico and in vitro studies, new target discovery and validation, proof of principles and robustness of animal studies.

    Science.gov (United States)

    Andrade, E L; Bento, A F; Cavalli, J; Oliveira, S K; Freitas, C S; Marcon, R; Schwanke, R C; Siqueira, J M; Calixto, J B

    2016-10-24

    This review presents a historical overview of drug discovery and the non-clinical stages of the drug development process, from initial target identification and validation, through in silico assays and high throughput screening (HTS), identification of leader molecules and their optimization, the selection of a candidate substance for clinical development, and the use of animal models during the early studies of proof-of-concept (or principle). This report also discusses the relevance of validated and predictive animal models selection, as well as the correct use of animal tests concerning the experimental design, execution and interpretation, which affect the reproducibility, quality and reliability of non-clinical studies necessary to translate to and support clinical studies. Collectively, improving these aspects will certainly contribute to the robustness of both scientific publications and the translation of new substances to clinical development.

  10. Non-clinical studies required for new drug development - Part I: early in silico and in vitro studies, new target discovery and validation, proof of principles and robustness of animal studies

    Directory of Open Access Journals (Sweden)

    E.L. Andrade

    Full Text Available This review presents a historical overview of drug discovery and the non-clinical stages of the drug development process, from initial target identification and validation, through in silico assays and high throughput screening (HTS, identification of leader molecules and their optimization, the selection of a candidate substance for clinical development, and the use of animal models during the early studies of proof-of-concept (or principle. This report also discusses the relevance of validated and predictive animal models selection, as well as the correct use of animal tests concerning the experimental design, execution and interpretation, which affect the reproducibility, quality and reliability of non-clinical studies necessary to translate to and support clinical studies. Collectively, improving these aspects will certainly contribute to the robustness of both scientific publications and the translation of new substances to clinical development.

  11. The robust regulation problem with robust stability

    NARCIS (Netherlands)

    Cevik, M.K.K.; Schumacher, J.M.

    1999-01-01

    Among the most common purposes of control are the tracking of reference signals and the rejection of disturbance signals in the face of uncertainties. The related design problem is called the `robust regulation problem'. Here we investigate the trade-off between the robust regulation constraint and

  12. Robustness of Structures

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2011-01-01

    ways and on different levels of complexity / applicability. On the most general level robustness is assessed taking basis in decision analysis theory by estimating both direct risk, which is associated with the direct consequences of potential damages to the structure, and indirect risk, which......An important aspect of the COST Action TU0601 “Robustness of structures” concerns the development of a theoretically sound basis for the assessment of robustness and acceptance criteria for structural robustness which can form the basis for development of practical relevant methods for ensuring...... robust design as well as strategies for maintaining the robustness of existing structures throughout their service life. This paper describes an overall theoretical framework for assessing robustness of structures developed within WG1 “Robustness of structures”. Robustness can be defined in different...

  13. Regulatory requirements for providing adequate veterinary care to research animals.

    Science.gov (United States)

    Pinson, David M

    2013-09-01

    Provision of adequate veterinary care is a required component of animal care and use programs in the United States. Program participants other than veterinarians, including non-medically trained research personnel and technicians, also provide veterinary care to animals, and administrators are responsible for assuring compliance with federal mandates regarding adequate veterinary care. All program participants therefore should understand the regulatory requirements for providing such care. The author provides a training primer on the US regulatory requirements for the provision of veterinary care to research animals. Understanding the legal basis and conditions of a program of veterinary care will help program participants to meet the requirements advanced in the laws and policies.

  14. Is the Stock of VET Skills Adequate? Assessment Methodologies.

    Science.gov (United States)

    Blandy, Richard; Freeland, Brett

    In Australia and elsewhere, four approaches have been used to determine whether stocks of vocational education and training (VET) skills are adequate to meet industry needs. The four methods are as follows: (1) the manpower requirements approach; (2) the international, national, and industry comparisons approach; (3) the labor market analysis…

  15. Quasi-Type δ Semigroups with an Adequate Transversal

    Institute of Scientific and Technical Information of China (English)

    Shou Feng WANG

    2011-01-01

    In this paper,some properties of quasi-type δ semigroups with an adequate transversal are explored.In particular,abundant semigroups with a cancellative transversal are characterized.Our results generalize and enrich Saito's results on quasi-orthodox semigroups with an inverse transversal.

  16. What is an Adequate Standard of Living During Retirement?

    NARCIS (Netherlands)

    Binswanger, J.; Schunk, D.

    2008-01-01

    Many economists and policy-makers argue that households do not save enough to maintain an adequate standard of living during retirement. However, there is no consensus on the answer to the underlying question what this standard should be, despite the fact that it is crucial for the design of saving

  17. 4 CFR 200.14 - Responsibility for maintaining adequate safeguards.

    Science.gov (United States)

    2010-01-01

    ... identifiable personal data and automated systems shall be adequately trained in the security and privacy of... records in which identifiable personal data are processed or maintained, including all reports and output... personal records or data; must minimize, to the extent practicable, the risk that skilled technicians...

  18. Robustness of Structural Systems

    DEFF Research Database (Denmark)

    Canisius, T.D.G.; Sørensen, John Dalsgaard; Baker, J.W.

    2007-01-01

    attempted to quantify aspects of robustness such as redundancy and identify design principles that can improve robustness. This paper outlines the progress of recent work by the Joint Committee on Structural Safety (JCSS) to develop comprehensive guidance on assessing and providing robustness in structural...... will be proposed. The document adopts a probabilistic risk assessment framework and includes guidance for decision-making related to robustness....

  19. Arabidopsis: an adequate model for dicot root systems?

    OpenAIRE

    Zobel, Richard W.

    2016-01-01

    The Arabidopsis root system is frequently considered to have only three classes of root: primary, lateral, and adventitious. Research with other plant species has suggested up to 8 different developmental/functional classes of root for a given plant root system. If Arabidopsis has only three classes of root, it may not be an adequate model for eudicot plant root systems. Recent research, however, can be interpreted to suggest that pre-flowering Arabidopsis does have at least five (5) of th...

  20. Arabidopsis: An Adequate Model for Dicot Root Systems?

    OpenAIRE

    Zobel, Richard W.

    2016-01-01

    The Arabidopsis root system is frequently considered to have only three classes of root: primary, lateral, and adventitious. Research with other plant species has suggested up to eight different developmental/functional classes of root for a given plant root system. If Arabidopsis has only three classes of root, it may not be an adequate model for eudicot plant root systems. Recent research, however, can be interpreted to suggest that pre-flowering Arabidopsis does have at least five (5) of t...

  1. Robust Regression and Lasso

    CERN Document Server

    Xu, Huan; Mannor, Shie

    2008-01-01

    Lasso, or $\\ell^1$ regularized least squares, has been explored extensively for its remarkable sparsity properties. It is shown in this paper that the solution to Lasso, in addition to its sparsity, has robustness properties: it is the solution to a robust optimization problem. This has two important consequences. First, robustness provides a connection of the regularizer to a physical property, namely, protection from noise. This allows a principled selection of the regularizer, and in particular, generalizations of Lasso that also yield convex optimization problems are obtained by considering different uncertainty sets. Secondly, robustness can itself be used as an avenue to exploring different properties of the solution. In particular, it is shown that robustness of the solution explains why the solution is sparse. The analysis as well as the specific results obtained differ from standard sparsity results, providing different geometric intuition. Furthermore, it is shown that the robust optimization formul...

  2. Developing an adequate "pneumatraumatology": understanding the spiritual impacts of traumatic injury.

    Science.gov (United States)

    Bidwell, Duane R

    2002-01-01

    Psychosocial interventions and systematic theology are primary resources for chaplains and congregational pastors who care for victims of physical trauma. Yet these resources may not be adequate to address the spiritual impacts of trauma. This article proposes a preliminary "pneumatraumatology," drawing on early Christian asceticism and Buddhist mysticism to describe one way of understanding the spiritual impacts of traumatic injury. It also suggests possible responses to these impacts informed by narrative/constructionist perspectives and Breggemann's understanding of the dimensions of spiritual transformation in the Hebrew Bible.

  3. Robust Geometric Spanners

    CERN Document Server

    Bose, Prosenjit; Morin, Pat; Smid, Michiel

    2012-01-01

    Highly connected and yet sparse graphs (such as expanders or graphs of high treewidth) are fundamental, widely applicable and extensively studied combinatorial objects. We initiate the study of such highly connected graphs that are, in addition, geometric spanners. We define a property of spanners called robustness. Informally, when one removes a few vertices from a robust spanner, this harms only a small number of other vertices. We show that robust spanners must have a superlinear number of edges, even in one dimension. On the positive side, we give constructions, for any dimension, of robust spanners with a near-linear number of edges.

  4. Genetic modification of preimplantation embryos: toward adequate human research policies.

    Science.gov (United States)

    Dresser, Rebecca

    2004-01-01

    Citing advances in transgenic animal research and setbacks in human trials of somatic cell genetic interventions, some scientists and others want to begin planning for research involving the genetic modification of human embryos. Because this form of genetic modification could affect later-born children and their offspring, the protection of human subjects should be a priority in decisions about whether to proceed with such research. Yet because of gaps in existing federal policies, embryo modification proposals might not receive adequate scientific and ethical scrutiny. This article describes current policy shortcomings and recommends policy actions designed to ensure that the investigational genetic modification of embryos meets accepted standards for research on human subjects.

  5. Is prophetic discourse adequate to address global economic justice?

    Directory of Open Access Journals (Sweden)

    Piet J. Naudé

    2011-06-01

    Full Text Available This article outlined key features of prophetic discourse and investigated whether this form of moral discourse adequately addresses issues of economic injustice. It is shown that the strength of prophetic discourse is its ability to denounce instances of injustice whilst at the same time announcing a God-willed alternative future. The ‘preferential option for the poor’ in Latin American liberation theologies is treated as a case study of the influence of prophetic discourse in contexts of perceived economic injustice. Also the core weaknesses of prophetic discourse are investigated, specifically its incomplete moral argument, weak moral analyses, silence on transition measures, and its inability to take a positive stance on reforms in the system from which itself benefits. In the final section it is concluded that prophetic discourse plays an indispensable role in addressing issues of global economic justice, but – taken by itself – it is not an adequate form of moral discourse to address concrete matters of justice.

  6. Robustness of networks

    NARCIS (Netherlands)

    Wang, H.

    2009-01-01

    Our society depends more strongly than ever on large networks such as transportation networks, the Internet and power grids. Engineers are confronted with fundamental questions such as “how to evaluate the robustness of networks for a given service?”, “how to design a robust network?”, because netwo

  7. Mechanisms for Robust Cognition

    Science.gov (United States)

    Walsh, Matthew M.; Gluck, Kevin A.

    2015-01-01

    To function well in an unpredictable environment using unreliable components, a system must have a high degree of robustness. Robustness is fundamental to biological systems and is an objective in the design of engineered systems such as airplane engines and buildings. Cognitive systems, like biological and engineered systems, exist within…

  8. Identification of children with reading difficulties: Cheap can be adequate

    DEFF Research Database (Denmark)

    Poulsen, Mads; Nielsen, Anne-Mette Veber

    Classification of reading difficulties: Cheap screening can be accurate Purpose: Three factors are important for identification of students in need of remedial instruction: accuracy, timeliness, and cost. The identification has to be accurate to be of any use, the identification has to be timely ...... in mid Grade 1 provided good classification. Choice of early intervention based on Grade 0 results should take into account the potential high cost of many false positives....... to allow for optimal remediation, and the procedure should preferably be inexpensive to allow wide-spread adoption. These criteria are, however, often in conflict: Early screening may be less accurate than late screening, and comprehensive and expensive testing is possibly more accurate than simple......, inexpensive testing. The present study investigated the classification accuracy of three screening models varying in timeliness and cost. Method: We compared the ROC statistics of three logistic models for predicting end of Grade 2 reading difficulties in a sample of 164 students: 1) an early, comprehensive...

  9. Developmental origins of metabolic disorders: The need for biomarker candidates and therapeutic targets from adequate preclinical models

    Directory of Open Access Journals (Sweden)

    Antonio Gonzalez-Bulnes

    2016-03-01

    Full Text Available The investigation on obesity and associated disorders have changed from an scenario in which genome drove the phenotype to a dynamic setup in which prenatal and early-postnatal conditions are determinant. However, research in human beings is difficult due to confounding factors (lifestyle and socioeconomic heterogeneity plus ethical issues. Hence, there is currently an intensive effort for developing adequate preclinical models, aiming for an adequate combination of basic studies in rodent models and specific preclinical studies in large animals. The results of these research strategies may increase the identification and development of contrasted biomarkers and therapeutic targets.

  10. MULTIDISCIPLINARY ROBUST OPTIMIZATION DESIGN

    Institute of Scientific and Technical Information of China (English)

    Chen Jianjiang; Xiao Renbin; Zhong Yifang; Dou Gang

    2005-01-01

    Because uncertainty factors inevitably exist under multidisciplinary design environment, a hierarchical multidisciplinary robust optimization design based on response surface is proposed. The method constructs optimization model of subsystem level and system level to coordinate the coupling among subsystems, and also the response surface based on the artificial neural network is introduced to provide information for system level optimization tool to maintain the independence of subsystems,i.e. to realize multidisciplinary parallel design. The application case of electrical packaging demonstrates that reasonable robust optimum solution can be yielded and it is a potential and efficient multidisciplinary robust optimization approach.

  11. Robustness of Structures

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2008-01-01

    . According to Danish design rules robustness shall be documented for all structures in high consequence class. The design procedure to document sufficient robustness consists of: 1) Review of loads and possible failure modes / scenarios and determination of acceptable collapse extent; 2) Review......This paper describes the background of the robustness requirements implemented in the Danish Code of Practice for Safety of Structures and in the Danish National Annex to the Eurocode 0, see (DS-INF 146, 2003), (DS 409, 2006), (EN 1990 DK NA, 2007) and (Sørensen and Christensen, 2006). More...... frequent use of advanced types of structures with limited redundancy and serious consequences in case of failure combined with increased requirements to efficiency in design and execution followed by increased risk of human errors has made the need of requirements to robustness of new structures essential...

  12. Robustness - theoretical framework

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Rizzuto, Enrico; Faber, Michael H.

    2010-01-01

    More frequent use of advanced types of structures with limited redundancy and serious consequences in case of failure combined with increased requirements to efficiency in design and execution followed by increased risk of human errors has made the need of requirements to robustness of new struct...... of this fact sheet is to describe a theoretical and risk based framework to form the basis for quantification of robustness and for pre-normative guidelines....

  13. Robust Nonstationary Regression

    OpenAIRE

    1993-01-01

    This paper provides a robust statistical approach to nonstationary time series regression and inference. Fully modified extensions of traditional robust statistical procedures are developed which allow for endogeneities in the nonstationary regressors and serial dependence in the shocks that drive the regressors and the errors that appear in the equation being estimated. The suggested estimators involve semiparametric corrections to accommodate these possibilities and they belong to the same ...

  14. Deferasirox pharmacokinetics in patients with adequate versus inadequate response

    Science.gov (United States)

    Chirnomas, Deborah; Smith, Amber Lynn; Braunstein, Jennifer; Finkelstein, Yaron; Pereira, Luis; Bergmann, Anke K.; Grant, Frederick D.; Paley, Carole; Shannon, Michael

    2009-01-01

    Tens of thousands of transfusion-dependent (eg, thalassemia) patients worldwide suffer from chronic iron overload and its potentially fatal complications. The oral iron chelator deferasirox has become commercially available in many countries since 2006. Although this alternative to parenteral deferoxamine has been a major advance for patients with transfusional hemosiderosis, a proportion of patients have suboptimal response to the maximum approved doses (30 mg/kg per day), and do not achieve negative iron balance. We performed a prospective study of oral deferasirox pharmacokinetics (PK), comparing 10 transfused patients with inadequate deferasirox response (rising ferritin trend or rising liver iron on deferasirox doses > 30 mg/kg per day) with control transfusion-dependent patients (n = 5) with adequate response. Subjects were admitted for 4 assessments: deferoxamine infusion and urinary iron measurement to assess readily chelatable iron; quantitative hepatobiliary scintigraphy to assess hepatic uptake and excretion of chelate; a 24-hour deferasirox PK study following a single 35-mg/kg dose of oral deferasirox; and pharmacogenomic analysis. Patients with inadequate response to deferasirox had significantly lower systemic drug exposure compared with control patients (P < .00001). Cmax, volume of distribution/bioavailability (Vd/F), and elimination half-life (t1/2) were not different between the groups, suggesting bioavailability as the likely discriminant. Effective dosing regimens for inadequately responding patients to deferasirox must be determined. This trial has been registered at http://www.clinicaltrials.gov under identifier NCT00749515. PMID:19724055

  15. Dose Limits for Man do not Adequately Protect the Ecosystem

    Energy Technology Data Exchange (ETDEWEB)

    Higley, Kathryn A.; Alexakhin, Rudolf M.; McDonald, Joseph C.

    2004-08-01

    It has been known for quite some time that different organisms display differing degrees of sensitivity to the effects of ionizing radiations. Some microorganisms such as the bacterium Micrococcus radiodurans, along with many species of invertebrates, are extremely radio-resistant. Humans might be categorized as being relatively sensitive to radiation, and are a bit more resistant than some pine trees. Therefore, it could be argued that maintaining the dose limits necessary to protect humans will also result in the protection of most other species of flora and fauna. This concept is usually referred to as the anthropocentric approach. In other words, if man is protected then the environment is also adequately protected. The ecocentric approach might be stated as; the health of humans is effectively protected only when the environment is not unduly exposed to radiation. The ICRP is working on new recommendations dealing with the protection of the environment, and this debate should help to highlight a number of relevant issues concerning that topic.

  16. Acute isoniazid toxicity and the need for adequate pyridoxine supplies.

    Science.gov (United States)

    Morrow, Lee E; Wear, Robert E; Schuller, Dan; Malesker, Mark

    2006-10-01

    A 25-year-old, 54-kg Hispanic man who had recently started multidrug therapy for pulmonary tuberculosis presented in status epilepticus after ingesting 9 g of isoniazid in a suicide attempt. Successful management of this patient required collaboration between several institutions to provide the large amount of necessary intravenous pyridoxine. Ultimately, this single overdose depleted the supply of intravenous pyridoxine for a significant region of the state of Nebraska. Isoniazid is commonly used to treat tuberculosis, but it is encountered relatively infrequently as the cause of an acute overdose. Severe isoniazid overdoses may present as seizure activity that is refractory to conventional antiepileptic therapy. Although intravenous pyridoxine is an effective antidote for isoniazid overdoses in patients presenting with status epilepticus, this agent has few indications and is typically stocked in limited quantities. In regions with large populations of patients who receive antituberculosis therapy, collaborative networks must be created to ensure that adequate supplies of intravenous pyridoxine (> or = 20 g) are available for effective treatment of isoniazid poisonings.

  17. Improving access to adequate pain management in Taiwan.

    Science.gov (United States)

    Scholten, Willem

    2015-06-01

    There is a global crisis in access to pain management in the world. WHO estimates that 4.65 billion people live in countries where medical opioid consumption is near to zero. For 2010, WHO considered a per capita consumption of 216.7 mg morphine equivalents adequate, while Taiwan had a per capita consumption of 0.05 mg morphine equivalents in 2007. In Asia, the use of opioids is sensitive because of the Opium Wars in the 19th century and for this reason, the focus of controlled substances policies has been on the prevention of diversion and dependence. However, an optimal public health outcome requires that also the beneficial aspects of these substances are acknowledged. Therefore, WHO recommends a policy based on the Principle of Balance: ensuring access for medical and scientific purposes while preventing diversion, harmful use and dependence. Furthermore, international law requires that countries ensure access to opioid analgesics for medical and scientific purposes. There is evidence that opioid analgesics for chronic pain are not associated with a major risk for developing dependence. Barriers for access can be classified in the categories of overly restrictive laws and regulations; insufficient medical training on pain management and problems related to assessment of medical needs; attitudes like an excessive fear for dependence or diversion; and economic and logistical problems. The GOPI project found many examples of such barriers in Asia. Access to opioid medicines in Taiwan can be improved by analysing the national situation and drafting a plan. The WHO policy guidelines Ensuring Balance in National Policies on Controlled Substances can be helpful for achieving this purpose, as well as international guidelines for pain treatment.

  18. Monitoring the eye lens: which dose quantity is adequate?

    Energy Technology Data Exchange (ETDEWEB)

    Behrens, R [Physikalisch-Technische Bundesanstalt, Bundesallee 100, D-38116 Braunschweig (Germany); Dietze, G, E-mail: rolf.behrens@ptb.d [Paracelsusstrasse 7, D-38116 Braunschweig (Germany)

    2010-07-21

    Recent epidemiological studies suggest a rather low dose threshold (below 0.5 Gy) for the induction of a cataract of the eye lens. Some other studies even assume that there is no threshold at all. Therefore, protection measures have to be optimized and current dose limits for the eye lens may be reduced in the future. The question of which personal dose equivalent quantity is appropriate for monitoring the dose to the eye lens arises from this situation. While in many countries dosemeters calibrated in terms of the dose equivalent quantity H{sub p}(0.07) have been seen as being adequate for monitoring the dose to the eye lens, this might be questionable in the case of reduced dose limits and, thus, it may become necessary to use the dose equivalent quantity H{sub p}(3) for this purpose. To discuss this question, the dose conversion coefficients for the equivalent dose of the eye lens (in the following eye lens dose) were determined for realistic photon and beta radiation fields and compared with the values of the corresponding conversion coefficients for the different operational quantities. The values obtained lead to the following conclusions: in radiation fields where most of the dose comes from photons, especially x-rays, it is appropriate to use dosemeters calibrated in terms of H{sub p}(0.07) on a slab phantom, while in other radiation fields (dominated by beta radiation or unknown contributions of photon and beta radiation) dosemeters calibrated in terms of H{sub p}(3) on a slab phantom should be used. As an alternative, dosemeters calibrated in terms of H{sub p}(0.07) on a slab phantom could also be used; however, in radiation fields containing beta radiation with the end point energy near 1 MeV, an overestimation of the eye lens dose by up to a factor of 550 is possible.

  19. Robustness in econometrics

    CERN Document Server

    Sriboonchitta, Songsak; Huynh, Van-Nam

    2017-01-01

    This book presents recent research on robustness in econometrics. Robust data processing techniques – i.e., techniques that yield results minimally affected by outliers – and their applications to real-life economic and financial situations are the main focus of this book. The book also discusses applications of more traditional statistical techniques to econometric problems. Econometrics is a branch of economics that uses mathematical (especially statistical) methods to analyze economic systems, to forecast economic and financial dynamics, and to develop strategies for achieving desirable economic performance. In day-by-day data, we often encounter outliers that do not reflect the long-term economic trends, e.g., unexpected and abrupt fluctuations. As such, it is important to develop robust data processing techniques that can accommodate these fluctuations.

  20. Robustness of Spatial Micronetworks

    CERN Document Server

    McAndrew, Thomas C; Bagrow, James P

    2015-01-01

    Power lines, roadways, pipelines and other physical infrastructure are critical to modern society. These structures may be viewed as spatial networks where geographic distances play a role in the functionality and construction cost of links. Traditionally, studies of network robustness have primarily considered the connectedness of large, random networks. Yet for spatial infrastructure physical distances must also play a role in network robustness. Understanding the robustness of small spatial networks is particularly important with the increasing interest in microgrids, small-area distributed power grids that are well suited to using renewable energy resources. We study the random failures of links in small networks where functionality depends on both spatial distance and topological connectedness. By introducing a percolation model where the failure of each link is proportional to its spatial length, we find that, when failures depend on spatial distances, networks are more fragile than expected. Accounting...

  1. Robustness - acceptance criteria

    DEFF Research Database (Denmark)

    Rizzuto, Enrico; Sørensen, John Dalsgaard; Kroon, Inger B.

    2010-01-01

    This factsheet describes the general framework on the bases of which acceptance criteria for requirements on the robustness of structures can be set. Such framework is based on the more general concept of risk-based assessment of engineering systems. The present factsheet is to be seen in conjunc......This factsheet describes the general framework on the bases of which acceptance criteria for requirements on the robustness of structures can be set. Such framework is based on the more general concept of risk-based assessment of engineering systems. The present factsheet is to be seen...... in conjunction with the one on the theoretical framework for robustness (Sørensen et al. 2009). In the present factsheet, the focus is on normative implications....

  2. Robust Manufacturing Control

    CERN Document Server

    2013-01-01

    This contributed volume collects research papers, presented at the CIRP Sponsored Conference Robust Manufacturing Control: Innovative and Interdisciplinary Approaches for Global Networks (RoMaC 2012, Jacobs University, Bremen, Germany, June 18th-20th 2012). These research papers present the latest developments and new ideas focusing on robust manufacturing control for global networks. Today, Global Production Networks (i.e. the nexus of interconnected material and information flows through which products and services are manufactured, assembled and distributed) are confronted with and expected to adapt to: sudden and unpredictable large-scale changes of important parameters which are occurring more and more frequently, event propagation in networks with high degree of interconnectivity which leads to unforeseen fluctuations, and non-equilibrium states which increasingly characterize daily business. These multi-scale changes deeply influence logistic target achievement and call for robust planning and control ...

  3. Factorisable Quasi-adequate Semigroups%因子拟适当半群

    Institute of Scientific and Technical Information of China (English)

    彭婷婷; 郭小江

    2011-01-01

    In this paper, we investigate a class of factorisable IC quasi-adequate semigroups,so-called, factorisable IC quasi-adequate semigroups of type-(H, I). Some characterizations of factorisable IC quasi-adequate semigroups of type-(H, I) are obtained. In particular, we prove that any IC quasi-adequate semigroup has a factorisable IC quasi-adequate subsemigroups of type-(H, I) and a band of cancellative monoids.

  4. Robust global motion estimation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A global motion estimation method based on robust statistics is presented in this paper. By using tracked feature points instead of whole image pixels to estimate parameters the process speeds up. To further speed up the process and avoid numerical instability, an alterative description of the problem is given, and three types of solution to the problem are compared. By using a two step process, the robustness of the estimator is also improved. Automatic initial value selection is an advantage of this method. The proposed approach is illustrated by a set of examples, which shows good results with high speed.

  5. Robustness of structures

    DEFF Research Database (Denmark)

    Vrouwenvelder, T.; Sørensen, John Dalsgaard

    2009-01-01

    robustness is still an issue of controversy and poses difficulties in regard to interpretation as well as regulation. Typically modern structural design codes require that ‘the consequence of damages to structures should not be disproportional to the causes of the damages'. However, despite the importance...

  6. Robustness via Diffractal Architectures

    CERN Document Server

    Moocarme, Matthew

    2015-01-01

    When plane waves diffract through fractal-patterned apertures, the resulting far-field profiles or diffractals also exhibit iterated, self-similar features. Here we show that this specific architecture enables robust signal processing and spatial multiplexing: arbitrary parts of a diffractal contain sufficient information to recreate the entire original sparse signal.

  7. Robustness Envelopes of Networks

    NARCIS (Netherlands)

    Trajanovski, S.; Martín-Hernández, J.; Winterbach, W.; Van Mieghem, P.

    2013-01-01

    We study the robustness of networks under node removal, considering random node failure, as well as targeted node attacks based on network centrality measures. Whilst both of these have been studied in the literature, existing approaches tend to study random failure in terms of average-case behavior

  8. Complexity, Robustness, and Performance

    NARCIS (Netherlands)

    B. Visser (Bauke)

    2002-01-01

    textabstractThis paper analyses the relationship between organizational complexity ( the degree of detail of information necessary to correctly assign agents to positions), robustness (the relative loss of performance due to mis-allocated agents), and performance. More complex structures are not nec

  9. Robustness of Structures

    DEFF Research Database (Denmark)

    Faber, M.H.; Vrouwenvelder, A.C.W.M.; Sørensen, John Dalsgaard;

    2011-01-01

    In 2005, the Joint Committee on Structural Safety (JCSS) together with Working Commission (WC) 1 of the International Association of Bridge and Structural Engineering (IABSE) organized a workshop on robustness of structures. Two important decisions resulted from this workshop, namely the developm...

  10. Teaching children with diabetes about adequate dietary choices.

    Science.gov (United States)

    Maffeis, Claudio; Pinelli, Leonardo

    2008-02-01

    Recent recommendations by the American Diabetes Association suggest that children with type 1 diabetes should follow the recommendations for age, sex and body size of the general population. In the case of being overweight or obese, weight-control strategies should be applied. Adherence to recommendations should be pursued by continuous nutritional education that should start at the onset of diabetes and maintained by means of nutritional counselling to the family. The second main target of nutritional intervention is to encourage a reproducible daily meal plan that can be maintained by acquiring good habits when making nutritional choices. Finally, children and parents should be taught how to count carbohydrates, which would help them manage exceptions in their daily meal plan. Specifically, nutritional recommendations for children with diabetes focus on limiting the intake of foods of animal origin (red meat, cheese, cold cuts), moderating fat intake and promoting the intake of foods that naturally contain fibre (mainly vegetables, legumes, fruit). There are two at-risk periods in the lives of children when nutritional education procedures as well as diabetes care in general are less likely to be effective: early years of life and adolescence. In the case of very young children, new behavioural-based intervention strategies to help parents improve mealtimes could be useful in teaching diabetic children to learn to follow a structured eating schedule, which is desirable for long-lasting efficacy in diabetes care. In adolescents, eating disorders and insulin misuse for weight control purposes are concrete and difficult problems to deal with. A good balance between eating for pleasure and maintaining one's health is a challenge for anyone. Appropriate nutritional education helps children with diabetes to find this balance and enjoy a better quality of life.

  11. Comparing dependent robust correlations.

    Science.gov (United States)

    Wilcox, Rand R

    2016-11-01

    Let r1 and r2 be two dependent estimates of Pearson's correlation. There is a substantial literature on testing H0  : ρ1  = ρ2 , the hypothesis that the population correlation coefficients are equal. However, it is well known that Pearson's correlation is not robust. Even a single outlier can have a substantial impact on Pearson's correlation, resulting in a misleading understanding about the strength of the association among the bulk of the points. A way of mitigating this concern is to use a correlation coefficient that guards against outliers, many of which have been proposed. But apparently there are no results on how to compare dependent robust correlation coefficients when there is heteroscedasicity. Extant results suggest that a basic percentile bootstrap will perform reasonably well. This paper reports simulation results indicating the extent to which this is true when using Spearman's rho, a Winsorized correlation or a skipped correlation.

  12. A robust classic.

    Science.gov (United States)

    Kutzner, Florian; Vogel, Tobias; Freytag, Peter; Fiedler, Klaus

    2011-01-01

    In the present research, we argue for the robustness of illusory correlations (ICs, Hamilton & Gifford, 1976) regarding two boundary conditions suggested in previous research. First, we argue that ICs are maintained under extended experience. Using simulations, we derive conflicting predictions. Whereas noise-based accounts predict ICs to be maintained (Fielder, 2000; Smith, 1991), a prominent account based on discrepancy-reducing feedback learning predicts ICs to disappear (Van Rooy et al., 2003). An experiment involving 320 observations with majority and minority members supports the claim that ICs are maintained. Second, we show that actively using the stereotype to make predictions that are met with reward and punishment does not eliminate the bias. In addition, participants' operant reactions afford a novel online measure of ICs. In sum, our findings highlight the robustness of ICs that can be explained as a result of unbiased but noisy learning.

  13. Robust verification analysis

    Energy Technology Data Exchange (ETDEWEB)

    Rider, William, E-mail: wjrider@sandia.gov [Sandia National Laboratories, Center for Computing Research, Albuquerque, NM 87185 (United States); Witkowski, Walt [Sandia National Laboratories, Verification and Validation, Uncertainty Quantification, Credibility Processes Department, Engineering Sciences Center, Albuquerque, NM 87185 (United States); Kamm, James R. [Los Alamos National Laboratory, Methods and Algorithms Group, Computational Physics Division, Los Alamos, NM 87545 (United States); Wildey, Tim [Sandia National Laboratories, Center for Computing Research, Albuquerque, NM 87185 (United States)

    2016-02-15

    We introduce a new methodology for inferring the accuracy of computational simulations through the practice of solution verification. We demonstrate this methodology on examples from computational heat transfer, fluid dynamics and radiation transport. Our methodology is suited to both well- and ill-behaved sequences of simulations. Our approach to the analysis of these sequences of simulations incorporates expert judgment into the process directly via a flexible optimization framework, and the application of robust statistics. The expert judgment is systematically applied as constraints to the analysis, and together with the robust statistics guards against over-emphasis on anomalous analysis results. We have named our methodology Robust Verification. Our methodology is based on utilizing multiple constrained optimization problems to solve the verification model in a manner that varies the analysis' underlying assumptions. Constraints applied in the analysis can include expert judgment regarding convergence rates (bounds and expectations) as well as bounding values for physical quantities (e.g., positivity of energy or density). This approach then produces a number of error models, which are then analyzed through robust statistical techniques (median instead of mean statistics). This provides self-contained, data and expert informed error estimation including uncertainties for both the solution itself and order of convergence. Our method produces high quality results for the well-behaved cases relatively consistent with existing practice. The methodology can also produce reliable results for ill-behaved circumstances predicated on appropriate expert judgment. We demonstrate the method and compare the results with standard approaches used for both code and solution verification on well-behaved and ill-behaved simulations.

  14. Robust Adaptive Control.

    Science.gov (United States)

    1985-09-19

    13.2 3.6. 14.0. 1.8. 11111.52 *.6 L 3 n1 i erated ~~~m nc. AFOSR-TR- 798 s AD-A 161 349 ROBUST ADAPTIVE CONTROL * FINAL REPORT PREPARED BY: R~ OBERT L... Centre Block Computes the Norm of the [1I] Solo, V., "Time Series Recursions and Stochastc Regressors. The Rematning Elemerts Imple- Approximation

  15. Robustness of Interdependent Networks

    Science.gov (United States)

    Havlin, Shlomo

    2011-03-01

    In interdependent networks, when nodes in one network fail, they cause dependent nodes in other networks to also fail. This may happen recursively and can lead to a cascade of failures. In fact, a failure of a very small fraction of nodes in one network may lead to the complete fragmentation of a system of many interdependent networks. We will present a framework for understanding the robustness of interacting networks subject to such cascading failures and provide a basic analytic approach that may be useful in future studies. We present exact analytical solutions for the critical fraction of nodes that upon removal will lead to a failure cascade and to a complete fragmentation of two interdependent networks in a first order transition. Surprisingly, analyzing complex systems as a set of interdependent networks may alter a basic assumption that network theory has relied on: while for a single network a broader degree distribution of the network nodes results in the network being more robust to random failures, for interdependent networks, the broader the distribution is, the more vulnerable the networks become to random failure. We also show that reducing the coupling between the networks leads to a change from a first order percolation phase transition to a second order percolation transition at a critical point. These findings pose a significant challenge to the future design of robust networks that need to consider the unique properties of interdependent networks.

  16. The Crane Robust Control

    Directory of Open Access Journals (Sweden)

    Marek Hicar

    2004-01-01

    Full Text Available The article is about a control design for complete structure of the crane: crab, bridge and crane uplift.The most important unknown parameters for simulations are burden weight and length of hanging rope. We will use robustcontrol for crab and bridge control to ensure adaptivity for burden weight and rope length. Robust control will be designed for current control of the crab and bridge, necessary is to know the range of unknown parameters. Whole robust will be splitto subintervals and after correct identification of unknown parameters the most suitable robust controllers will be chosen.The most important condition at the crab and bridge motion is avoiding from burden swinging in the final position. Crab and bridge drive is designed by asynchronous motor fed from frequency converter. We will use crane uplift with burden weightobserver in combination for uplift, crab and bridge drive with cooperation of their parameters: burden weight, rope length and crab and bridge position. Controllers are designed by state control method. We will use preferably a disturbance observerwhich will identify burden weight as a disturbance. The system will be working in both modes at empty hook as well asat maximum load: burden uplifting and dropping down.

  17. Real Time & Power Efficient Adaptive - Robust Control

    Science.gov (United States)

    Ioan Gliga, Lavinius; Constantin Mihai, Cosmin; Lupu, Ciprian; Popescu, Dumitru

    2017-01-01

    A design procedure for a control system suited for dynamic variable processes is presented in this paper. The proposed adaptive - robust control strategy considers both adaptive control advantages and robust control benefits. It estimates the degradation of the system’s performances due to the dynamic variation in the process and it then utilizes it to determine when the system must be adapted with a redesign of the robust controller. A single integral criterion is used for the identification of the process, and for the design of the control algorithm, which is expressed in direct form, through a cost function defined in the space of the parameters of both the process and the controller. For the minimization of this nonlinear function, an adequate mathematical programming minimization method is used. The theoretical approach presented in this paper was validated for a closed loop control system, simulated in an application developed in C. Because of the reduced number of operations, this method is suitable for implementation on fast processes. Due to its effectiveness, it increases the idle time of the CPU, thereby saving electrical energy.

  18. Robust Kriged Kalman Filtering

    Energy Technology Data Exchange (ETDEWEB)

    Baingana, Brian; Dall' Anese, Emiliano; Mateos, Gonzalo; Giannakis, Georgios B.

    2015-11-11

    Although the kriged Kalman filter (KKF) has well-documented merits for prediction of spatial-temporal processes, its performance degrades in the presence of outliers due to anomalous events, or measurement equipment failures. This paper proposes a robust KKF model that explicitly accounts for presence of measurement outliers. Exploiting outlier sparsity, a novel l1-regularized estimator that jointly predicts the spatial-temporal process at unmonitored locations, while identifying measurement outliers is put forth. Numerical tests are conducted on a synthetic Internet protocol (IP) network, and real transformer load data. Test results corroborate the effectiveness of the novel estimator in joint spatial prediction and outlier identification.

  19. Robustness of Cantor diffractals.

    Science.gov (United States)

    Verma, Rupesh; Sharma, Manoj Kumar; Banerjee, Varsha; Senthilkumaran, Paramasivam

    2013-04-08

    Diffractals are electromagnetic waves diffracted by a fractal aperture. In an earlier paper, we reported an important property of Cantor diffractals, that of redundancy [R. Verma et. al., Opt. Express 20, 8250 (2012)]. In this paper, we report another important property, that of robustness. The question we address is: How much disorder in the Cantor grating can be accommodated by diffractals to continue to yield faithfully its fractal dimension and generator? This answer is of consequence in a number of physical problems involving fractal architecture.

  20. Robustness Metrics: Consolidating the multiple approaches to quantify Robustness

    DEFF Research Database (Denmark)

    Göhler, Simon Moritz; Eifler, Tobias; Howard, Thomas J.

    2016-01-01

    determined to be conceptually different from one another. The metrics were classified by their meaning and interpretation based on the types of information necessary to calculate the metrics. Four different classes were identified: 1) Sensitivity robustness metrics; 2) Size of feasible design space...... and to remove the ambiguities of the term robustness. By applying an exemplar metric from each class to a case study, the differences between the classes were further highlighted.These classes form the basis for the definition of four specific sub-definitions of robustness, namely the ‘robust concept’, ‘robust...

  1. Adaptive Robust Variable Selection

    CERN Document Server

    Fan, Jianqing; Barut, Emre

    2012-01-01

    Heavy-tailed high-dimensional data are commonly encountered in various scientific fields and pose great challenges to modern statistical analysis. A natural procedure to address this problem is to use penalized least absolute deviation (LAD) method with weighted $L_1$-penalty, called weighted robust Lasso (WR-Lasso), in which weights are introduced to ameliorate the bias problem induced by the $L_1$-penalty. In the ultra-high dimensional setting, where the dimensionality can grow exponentially with the sample size, we investigate the model selection oracle property and establish the asymptotic normality of the WR-Lasso. We show that only mild conditions on the model error distribution are needed. Our theoretical results also reveal that adaptive choice of the weight vector is essential for the WR-Lasso to enjoy these nice asymptotic properties. To make the WR-Lasso practically feasible, we propose a two-step procedure, called adaptive robust Lasso (AR-Lasso), in which the weight vector in the second step is c...

  2. Robust Cultural Pluralism

    Directory of Open Access Journals (Sweden)

    Richard A. Shweder

    2013-11-01

    Full Text Available In this wide ranging interview, Professor Richard A. Shweder from the Department of Comparative Human Development at the University of Chicago, discusses whether it is or is not possible to be a robust cultural pluralist and a dedicated political liberal at the same time. In this discussion, Professor Shweder offers his insights - based on over 40 years of research - on issues related to the history and re-emergence of cultural psychology; moral anthropology and psychology; the experimental method in psychological investigation and its philosophical basis; contemporary and historical cultural collisions – most notably conflicting representations of female genital surgeries; cultural diversity and inequality; and the dissemination of ideas through open access publishing and Twitter. Professor Shweder ends by offering valuable advice to young researchers in the field of cultural psychology as well as a glimpse into the larger themes of his forthcoming book, which seeks to provide answers to the question of what forms of political liberalism are most compatible with robust cultural pluralism and which are not.

  3. International Conference on Robust Statistics

    CERN Document Server

    Filzmoser, Peter; Gather, Ursula; Rousseeuw, Peter

    2003-01-01

    Aspects of Robust Statistics are important in many areas. Based on the International Conference on Robust Statistics 2001 (ICORS 2001) in Vorau, Austria, this volume discusses future directions of the discipline, bringing together leading scientists, experienced researchers and practitioners, as well as younger researchers. The papers cover a multitude of different aspects of Robust Statistics. For instance, the fundamental problem of data summary (weights of evidence) is considered and its robustness properties are studied. Further theoretical subjects include e.g.: robust methods for skewness, time series, longitudinal data, multivariate methods, and tests. Some papers deal with computational aspects and algorithms. Finally, the aspects of application and programming tools complete the volume.

  4. Robust automated knowledge capture.

    Energy Technology Data Exchange (ETDEWEB)

    Stevens-Adams, Susan Marie; Abbott, Robert G.; Forsythe, James Chris; Trumbo, Michael Christopher Stefan; Haass, Michael Joseph; Hendrickson, Stacey M. Langfitt

    2011-10-01

    This report summarizes research conducted through the Sandia National Laboratories Robust Automated Knowledge Capture Laboratory Directed Research and Development project. The objective of this project was to advance scientific understanding of the influence of individual cognitive attributes on decision making. The project has developed a quantitative model known as RumRunner that has proven effective in predicting the propensity of an individual to shift strategies on the basis of task and experience related parameters. Three separate studies are described which have validated the basic RumRunner model. This work provides a basis for better understanding human decision making in high consequent national security applications, and in particular, the individual characteristics that underlie adaptive thinking.

  5. Robust Optical Flow Estimation

    Directory of Open Access Journals (Sweden)

    Javier Sánchez Pérez

    2013-10-01

    Full Text Available n this work, we describe an implementation of the variational method proposed by Brox etal. in 2004, which yields accurate optical flows with low running times. It has several benefitswith respect to the method of Horn and Schunck: it is more robust to the presence of outliers,produces piecewise-smooth flow fields and can cope with constant brightness changes. Thismethod relies on the brightness and gradient constancy assumptions, using the information ofthe image intensities and the image gradients to find correspondences. It also generalizes theuse of continuous L1 functionals, which help mitigate the effect of outliers and create a TotalVariation (TV regularization. Additionally, it introduces a simple temporal regularizationscheme that enforces a continuous temporal coherence of the flow fields.

  6. Robust procedures in chemometrics

    DEFF Research Database (Denmark)

    Kotwa, Ewelina

    -way chemometrical methods, such as PCA and PARAFAC models for analysing spatial and depth profiles of sea water samples, defined by three data modes: depth, variables and geographical location. Emphasis was also put on predicting fluorescence values, as being a natural measure of biological activity, by applying....... applying a multivariate and multi-way data analytical frame-work in fields where less sophisticated data analysis methods are currently used, and 2. developing new, more robust alternatives to already existing multivariate tools. The first part of the study was realised by applying two- and three...... and comparing the Partial Least Squares (PLS) regression technique with its multi-way alternative, N-PLS. Results of the analysis indicated superiority of the three-way frame-work, potentially constituting a novel assessment of the sea water measurements. Particularly in the case of regression models...

  7. Passion, Robustness and Perseverance

    DEFF Research Database (Denmark)

    Lim, Miguel Antonio; Lund, Rebecca

    2016-01-01

    Evaluation and merit in the measured university are increasingly based on taken-for-granted assumptions about the “ideal academic”. We suggest that the scholar now needs to show that she is passionate about her work and that she gains pleasure from pursuing her craft. We suggest that passion...... and pleasure achieve an exalted status as something compulsory. The scholar ought to feel passionate about her work and signal that she takes pleasure also in the difficult moments. Passion has become a signal of robustness and perseverance in a job market characterised by funding shortages, increased pressure...... to produce measurable output, and precariousness. For young academics in particular it is increasingly important to demonstrate the “right attitude”, “feelings”, and “personality traits” because they have yet to accumulate a record of past achievements that are used as the basis of merit. In hiring decisions...

  8. Validation of community robustness

    CERN Document Server

    Carissimo, Annamaria; Defeis, Italia

    2016-01-01

    The large amount of work on community detection and its applications leaves unaddressed one important question: the statistical validation of the results. In this paper we present a methodology able to clearly detect if the community structure found by some algorithms is statistically significant or is a result of chance, merely due to edge positions in the network. Given a community detection method and a network of interest, our proposal examines the stability of the partition recovered against random perturbations of the original graph structure. To address this issue, we specify a perturbation strategy and a null model to build a set of procedures based on a special measure of clustering distance, namely Variation of Information, using tools set up for functional data analysis. The procedures determine whether the obtained clustering departs significantly from the null model. This strongly supports the robustness against perturbation of the algorithm used to identify the community structure. We show the r...

  9. Provably robust digital watermarking

    Science.gov (United States)

    Chen, Brian; Wornell, Gregory W.

    1999-11-01

    Copyright notification and enforcement, authentication, covert communication, and hybrid transmission are examples of emerging multimedia applications for digital watermarking methods, methods for embedding one signal (e.g., the digital watermark) within another 'host' signal to form a third, 'composite' signal. The embedding is designed to achieve efficient trade-offs among the three conflicting goals of maximizing information-embedding rate, minimizing distortion between the host signal and composite signal, and maximizing the robustness of the embedding. Quantization index modulation (QIM) methods are a class of watermarking methods that achieve provably good rate-distortion-robustness performance. Indeed, QIM methods exist that achieve performance within a few dB of capacity in the case of a (possibly colored) Gaussian host signal and an additive (possibly colored) Gaussian noise channel. Also, QIM methods can achieve capacity with a type of postprocessing called distortion compensation. This capacity is independent of host signal statistics, and thus, contrary to popular belief, the information-embedding capacity when the host signal is not available at the decoder is the same as the case when the host signal is available at the decoder. A low-complexity realization of QIM called dither modulation has previously been proven to be better than both linear methods of spread spectrum and nonlinear methods of low-bit(s) modulation against square-error distortion-constrained intentional attacks. We introduce a new form of dither modulation called spread-transform dither modulation that retains these favorable performance characteristics while achieving better performance against other attacks such as JPEG compression.

  10. Robust Principal Component Analysis?

    CERN Document Server

    Candes, Emmanuel J; Ma, Yi; Wright, John

    2009-01-01

    This paper is about a curious phenomenon. Suppose we have a data matrix, which is the superposition of a low-rank component and a sparse component. Can we recover each component individually? We prove that under some suitable assumptions, it is possible to recover both the low-rank and the sparse components exactly by solving a very convenient convex program called Principal Component Pursuit; among all feasible decompositions, simply minimize a weighted combination of the nuclear norm and of the L1 norm. This suggests the possibility of a principled approach to robust principal component analysis since our methodology and results assert that one can recover the principal components of a data matrix even though a positive fraction of its entries are arbitrarily corrupted. This extends to the situation where a fraction of the entries are missing as well. We discuss an algorithm for solving this optimization problem, and present applications in the area of video surveillance, where our methodology allows for th...

  11. Robust relativistic bit commitment

    Science.gov (United States)

    Chakraborty, Kaushik; Chailloux, André; Leverrier, Anthony

    2016-12-01

    Relativistic cryptography exploits the fact that no information can travel faster than the speed of light in order to obtain security guarantees that cannot be achieved from the laws of quantum mechanics alone. Recently, Lunghi et al. [Phys. Rev. Lett. 115, 030502 (2015), 10.1103/PhysRevLett.115.030502] presented a bit-commitment scheme where each party uses two agents that exchange classical information in a synchronized fashion, and that is both hiding and binding. A caveat is that the commitment time is intrinsically limited by the spatial configuration of the players, and increasing this time requires the agents to exchange messages during the whole duration of the protocol. While such a solution remains computationally attractive, its practicality is severely limited in realistic settings since all communication must remain perfectly synchronized at all times. In this work, we introduce a robust protocol for relativistic bit commitment that tolerates failures of the classical communication network. This is done by adding a third agent to both parties. Our scheme provides a quadratic improvement in terms of expected sustain time compared with the original protocol, while retaining the same level of security.

  12. Robust Nonlinear Neural Codes

    Science.gov (United States)

    Yang, Qianli; Pitkow, Xaq

    2015-03-01

    Most interesting natural sensory stimuli are encoded in the brain in a form that can only be decoded nonlinearly. But despite being a core function of the brain, nonlinear population codes are rarely studied and poorly understood. Interestingly, the few existing models of nonlinear codes are inconsistent with known architectural features of the brain. In particular, these codes have information content that scales with the size of the cortical population, even if that violates the data processing inequality by exceeding the amount of information entering the sensory system. Here we provide a valid theory of nonlinear population codes by generalizing recent work on information-limiting correlations in linear population codes. Although these generalized, nonlinear information-limiting correlations bound the performance of any decoder, they also make decoding more robust to suboptimal computation, allowing many suboptimal decoders to achieve nearly the same efficiency as an optimal decoder. Although these correlations are extremely difficult to measure directly, particularly for nonlinear codes, we provide a simple, practical test by which one can use choice-related activity in small populations of neurons to determine whether decoding is suboptimal or optimal and limited by correlated noise. We conclude by describing an example computation in the vestibular system where this theory applies. QY and XP was supported by a grant from the McNair foundation.

  13. Robust correlation tracker

    Indian Academy of Sciences (India)

    M Sankar Kishore; K Veerabhadra Rao

    2001-06-01

    Correlation tracking plays an important role in the automation of weapon systems. Area correlation is an effective technique for tracking targets that have neither prominent features nor high contrast with the background and the ‘target’ can even be an area or a scene of interest. Even though this technique is robust under varying conditions of target background and light conditions, it has some problems like target drift and false registration. When the tracker or target is moving, the registration point drifts due to the discrete pixel size and aspect angle change. In this research work, an attempt has been made to improve the performance of a correlation tracker for tracking ground targets with very poor contrast. In the present work only the CCD visible images with very poor target to background contrast are considered. Applying novel linear and nonlinear filters, the problems present in the correlation tracker are overcome. Confidence and redundancy measures have been proposed to improve the performance by detecting misregistration. The proposed algorithm is tested on different sequences of images and its performance is satisfactory.

  14. Robustness Evaluation of Timber Structures

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Sørensen, John Dalsgaard

    2009-01-01

    The present paper considers robustness evaluation of a Norwegian sports arena with a structural system of glulam frames. The robustness evaluation is based on the framework for robustness analysis introduced in the Danish Code of Practice for the Safety of Structures and a probabilistic modelling...... of the timber material proposed in the Probabilistic Model Code (PMC) of the Joint Committee on Structural Safety (JCSS). The results show that the requirements for robustness of the structure are highly related to the modelling of the snow load used on the structures when ‘removal of a limited part...

  15. The enforceability of the human right to adequate food : a comparative study

    NARCIS (Netherlands)

    Wernaart, B.F.W.

    2013-01-01

    While the right to adequate food is often discussed in the context of developing countries, especially in situations where access to adequate food is a problem on a larger scale, this book focusses on the right to food in two Western countries in which theoretically the circumstances allow this righ

  16. In search of an adequate yet affordable tutor in online learning networks

    NARCIS (Netherlands)

    Sloep, Peter; Van Rosmalen, Peter; Kester, Liesbeth; Brouns, Francis; Koper, Rob

    2006-01-01

    Sloep, P., van Rosmalen, P., Kester, L., Brouns, F. M. R., & Koper, E. J. R. (2006). In search of an adequate yet affordable tutor in online learning networks. In search of an adequate yet affordable tutor in online learning networks. Presentation at the 6th IEEE International Conference on Advanced

  17. 9 CFR 2.33 - Attending veterinarian and adequate veterinary care.

    Science.gov (United States)

    2010-01-01

    ... veterinary care. 2.33 Section 2.33 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... adequate veterinary care. (a) Each research facility shall have an attending veterinarian who shall provide adequate veterinary care to its animals in compliance with this section: (1) Each research facility...

  18. Robust Understanding of Statistical Variation

    Science.gov (United States)

    Peters, Susan A.

    2011-01-01

    This paper presents a framework that captures the complexity of reasoning about variation in ways that are indicative of robust understanding and describes reasoning as a blend of design, data-centric, and modeling perspectives. Robust understanding is indicated by integrated reasoning about variation within each perspective and across…

  19. A Robust Enough Virtue Epistemology

    DEFF Research Database (Denmark)

    Broncano-Berrocal, Fernando

    2016-01-01

    What is the nature of knowledge? A popular answer to that long-standing question comes from robust virtue epistemology, whose key idea is that knowing is just a matter of succeeding cognitively—i.e., coming to believe a proposition truly—due to an exercise of cognitive ability. Versions of robust...

  20. A Robust Design Applicability Model

    DEFF Research Database (Denmark)

    Ebro, Martin; Lars, Krogstie; Howard, Thomas J.

    2015-01-01

    This paper introduces a model for assessing the applicability of Robust Design (RD) in a project or organisation. The intention of the Robust Design Applicability Model (RDAM) is to provide support for decisions by engineering management considering the relevant level of RD activities. The applic...

  1. Robust and distributed hypothesis testing

    CERN Document Server

    Gül, Gökhan

    2017-01-01

    This book generalizes and extends the available theory in robust and decentralized hypothesis testing. In particular, it presents a robust test for modeling errors which is independent from the assumptions that a sufficiently large number of samples is available, and that the distance is the KL-divergence. Here, the distance can be chosen from a much general model, which includes the KL-divergence as a very special case. This is then extended by various means. A minimax robust test that is robust against both outliers as well as modeling errors is presented. Minimax robustness properties of the given tests are also explicitly proven for fixed sample size and sequential probability ratio tests. The theory of robust detection is extended to robust estimation and the theory of robust distributed detection is extended to classes of distributions, which are not necessarily stochastically bounded. It is shown that the quantization functions for the decision rules can also be chosen as non-monotone. Finally, the boo...

  2. Minimax Robust Quickest Change Detection

    CERN Document Server

    Unnikrishnan, Jayakrishnan; Meyn, Sean

    2009-01-01

    The two popular criteria of optimality for quickest change detection procedures are Lorden's criterion and the Bayesian criterion. In this paper a robust version of these quickest change detection problems is considered when the pre-change and post-change distributions are not known exactly but belong to known uncertainty classes of distributions. For uncertainty classes that satisfy a specific condition, it is shown that one can identify least favorable distributions (LFDs) from the uncertainty classes, such that the detection rule designed for the LFDs is optimal for the robust problem in a minimax sense. The condition is similar to that required for the identification of LFDs for the robust hypothesis testing problem studied by Huber. An upper bound on the delay incurred by the robust test is also obtained in the asymptotic setting under Lorden's criterion of optimality, which quantifies the delay penalty incurred to guarantee robustness. When the LFDs can be identified, the proposed test is easier to impl...

  3. Graph measures and network robustness

    CERN Document Server

    Ellens, W

    2013-01-01

    Network robustness research aims at finding a measure to quantify network robustness. Once such a measure has been established, we will be able to compare networks, to improve existing networks and to design new networks that are able to continue to perform well when it is subject to failures or attacks. In this paper we survey a large amount of robustness measures on simple, undirected and unweighted graphs, in order to offer a tool for network administrators to evaluate and improve the robustness of their network. The measures discussed in this paper are based on the concepts of connectivity (including reliability polynomials), distance, betweenness and clustering. Some other measures are notions from spectral graph theory, more precisely, they are functions of the Laplacian eigenvalues. In addition to surveying these graph measures, the paper also contains a discussion of their functionality as a measure for topological network robustness.

  4. Robust statistical methods with R

    CERN Document Server

    Jureckova, Jana

    2005-01-01

    Robust statistical methods were developed to supplement the classical procedures when the data violate classical assumptions. They are ideally suited to applied research across a broad spectrum of study, yet most books on the subject are narrowly focused, overly theoretical, or simply outdated. Robust Statistical Methods with R provides a systematic treatment of robust procedures with an emphasis on practical application.The authors work from underlying mathematical tools to implementation, paying special attention to the computational aspects. They cover the whole range of robust methods, including differentiable statistical functions, distance of measures, influence functions, and asymptotic distributions, in a rigorous yet approachable manner. Highlighting hands-on problem solving, many examples and computational algorithms using the R software supplement the discussion. The book examines the characteristics of robustness, estimators of real parameter, large sample properties, and goodness-of-fit tests. It...

  5. Robustness or resilience? Managing the intersection of ecology and engineering in an urban Alaskan fishery

    OpenAIRE

    2014-01-01

    Systems theories of robustness and resilience, which are derived from engineering and ecology, respectively, have been increasingly applied to social-ecological systems (SESs). Social-ecological robustness has been applied primarily to management of physical dimensions of SESs (e.g., water management) and resilience to management of ecological dimensions of SESs (e.g., rangelands). However, cases of highly engineered systems have yet to be adequately evaluated by either approach. We find the ...

  6. Abundant Semigroups with Q-adequate Transversals and Some of Their Special Cases

    Institute of Scientific and Technical Information of China (English)

    Xiaojiang Guo; K.P. Shum

    2007-01-01

    Regular semigroups with multiplicative inverse transversals were first studied by Blyth and McFadden in 1982.In this paper, we extend the concept of inverse transversals to some kind of quasi-ideal adequate transversals of abundant semigroups.Some characterization theorems of abundant semigroups with different kinds of quasiideal adequate transversals are obtained. In particular, the structure theory of abundant semigroups having different kinds of quasi-ideal adequate transversals is established. Some results obtained by Blyth, McAlister and McFadden on inverse transversals in regular semigroups are hence extended to abundant semigroups.

  7. Auditory information processing during adequate propofol anesthesia monitored by electroencephalogram bispectral index

    NARCIS (Netherlands)

    C. Kerssens (Chantal); J. Klein (Jan); A. van der Woerd; B. Bonke (Benno)

    2001-01-01

    textabstractMemory for intraoperative events may arise from inadequate anesthesia when the hypnotic state is not continuously monitored. Electroencephalogram bispectral index (BIS) enables monitoring of the hypnotic state and titration of anesthesia to an adequate level

  8. Population genetics of translational robustness.

    Science.gov (United States)

    Wilke, Claus O; Drummond, D Allan

    2006-05-01

    Recent work has shown that expression level is the main predictor of a gene's evolutionary rate and that more highly expressed genes evolve slower. A possible explanation for this observation is selection for proteins that fold properly despite mistranslation, in short selection for translational robustness. Translational robustness leads to the somewhat paradoxical prediction that highly expressed genes are extremely tolerant to missense substitutions but nevertheless evolve very slowly. Here, we study a simple theoretical model of translational robustness that allows us to gain analytic insight into how this paradoxical behavior arises.

  9. Robustness Analysis of Kinetic Structures

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Sørensen, John Dalsgaard

    2009-01-01

    The present paper considers robustness of kinetic structures. Robustness of structures has obtained a renewed interest due to a much more frequent use of advanced types of structures with limited redundancy and serious consequences in case of failure. Especially for these types of structural syst...... systems, it is of interest to investigate how robust the structures are, or what happens if a structural element is added to or removed from the original structure. The present paper discusses this issue for kinetic structures in architecture....

  10. Robustness of airline route networks

    Science.gov (United States)

    Lordan, Oriol; Sallan, Jose M.; Escorihuela, Nuria; Gonzalez-Prieto, David

    2016-03-01

    Airlines shape their route network by defining their routes through supply and demand considerations, paying little attention to network performance indicators, such as network robustness. However, the collapse of an airline network can produce high financial costs for the airline and all its geographical area of influence. The aim of this study is to analyze the topology and robustness of the network route of airlines following Low Cost Carriers (LCCs) and Full Service Carriers (FSCs) business models. Results show that FSC hubs are more central than LCC bases in their route network. As a result, LCC route networks are more robust than FSC networks.

  11. Adequate sleep among adolescents is positively associated with health status and health-related behaviors

    OpenAIRE

    Jeng Yi-Jong; Wang Edward K; Chen Mei-Yen

    2006-01-01

    Abstract Background Amount of sleep is an important indicator of health and well-being in children and adolescents. Adequate sleep (AS: adequate sleep is defined as 6–8 hours per night regularly) is a critical factor in adolescent health and health-related behaviors. The present study was based on a health promotion project previously conducted on adolescents in Tao-Yuan County, Taiwan. The aim was to examine the relationship between AS during schooldays and excessive body weight, frequency o...

  12. Is protein-energy intake adequate during dialysis treatment in hemodialysis patients ?

    OpenAIRE

    Trudeke (G) I. Struijk-Wielinga; Najoua Zanaki; Maryam Hdoudou; Peter J.M. Weijs

    2012-01-01

    Protein-energy wasting (PEW) is a strong predictor of mortality in patients with chronic kidney disease. Although PEW is caused by non nutritional conditions, research indicates that nutritional support that targets adequate protein intake improves outcome. During dialysis therapy in-centre meals and snacks are provided. The question is whether these meals provide adequate protein and energy intake considering external (at home) consumed meals? Indirect calorimetry and physical activity Le...

  13. Individual and contextual determinants of adequate maternal health care services in Kenya.

    Science.gov (United States)

    Achia, Thomas N O; Mageto, Lillian E

    2015-01-01

    This study aimed to examine individual and community level factors associated with adequate use of maternal antenatal health services in Kenya. Individual and community level factors associated with adequate use of maternal health care (MHC) services were obtained from the 2008-09 Kenya Demographic and Health Survey data set. Multilevel partial-proportional odds logit models were fitted using STATA 13.0 to quantify the relations of the selected covariates to adequate MHC use, defined as a three-category ordinal variable. The sample consisted of 3,621 women who had at least one live birth in the five-year period preceding this survey. Only 18 percent of the women had adequate use of MHC services. Greater educational attainment by the woman or her partner, higher socioeconomic status, access to medical insurance coverage, and greater media exposure were the individual-level factors associated with adequate use of MHC services. Greater community ethnic diversity, higher community-level socioeconomic status, and greater community-level health facility deliveries were the contextual-level factors associated with adequate use of MHC. To improve the use of MHC services in Kenya, the government needs to design and implement programs that target underlying individual and community level factors, providing focused and sustained health education to promote the use of antenatal, delivery, and postnatal care.

  14. Robust Portfolio Optimization Using Pseudodistances.

    Science.gov (United States)

    Toma, Aida; Leoni-Aubin, Samuela

    2015-01-01

    The presence of outliers in financial asset returns is a frequently occurring phenomenon which may lead to unreliable mean-variance optimized portfolios. This fact is due to the unbounded influence that outliers can have on the mean returns and covariance estimators that are inputs in the optimization procedure. In this paper we present robust estimators of mean and covariance matrix obtained by minimizing an empirical version of a pseudodistance between the assumed model and the true model underlying the data. We prove and discuss theoretical properties of these estimators, such as affine equivariance, B-robustness, asymptotic normality and asymptotic relative efficiency. These estimators can be easily used in place of the classical estimators, thereby providing robust optimized portfolios. A Monte Carlo simulation study and applications to real data show the advantages of the proposed approach. We study both in-sample and out-of-sample performance of the proposed robust portfolios comparing them with some other portfolios known in literature.

  15. Multifidelity Robust Aeroelastic Design Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Nielsen Engineering & Research (NEAR) proposes a new method to generate mathematical models of wind-tunnel models and flight vehicles for robust aeroelastic...

  16. Shaping Robust System through Evolution

    CERN Document Server

    Kaneko, Kunihiko

    2008-01-01

    Biological functions are generated as a result of developmental dynamics that form phenotypes governed by genotypes. The dynamical system for development is shaped through genetic evolution following natural selection based on the fitness of the phenotype. Here we study how this dynamical system is robust to noise during development and to genetic change by mutation. We adopt a simplified transcription regulation network model to govern gene expression, which gives a fitness function. Through simulations of the network that undergoes mutation and selection, we show that a certain level of noise in gene expression is required for the network to acquire both types of robustness. The results reveal how the noise that cells encounter during development shapes any network's robustness, not only to noise but also to mutations. We also establish a relationship between developmental and mutational robustness through phenotypic variances caused by genetic variation and epigenetic noise. A universal relationship betwee...

  17. Robust Processing of Natural Language

    CERN Document Server

    Menzel, W

    1995-01-01

    Previous approaches to robustness in natural language processing usually treat deviant input by relaxing grammatical constraints whenever a successful analysis cannot be provided by ``normal'' means. This schema implies, that error detection always comes prior to error handling, a behaviour which hardly can compete with its human model, where many erroneous situations are treated without even noticing them. The paper analyses the necessary preconditions for achieving a higher degree of robustness in natural language processing and suggests a quite different approach based on a procedure for structural disambiguation. It not only offers the possibility to cope with robustness issues in a more natural way but eventually might be suited to accommodate quite different aspects of robust behaviour within a single framework.

  18. Population genetics of translational robustness

    OpenAIRE

    Wilke, Claus O; Drummond, D. Allan

    2005-01-01

    Recent work has shown that expression level is the main predictor of a gene’s evolutionary rate, and that more highly expressed genes evolve slower. A possible explanation for this observation is selection for proteins which fold properly despite mistranslation, in short selection for translational robustness. Translational robustness leads to the somewhat paradoxical prediction that highly expressed genes are extremely tolerant to missense substitutions but nevertheless evolve very slo...

  19. Robust inspection and interpretation techniques

    Energy Technology Data Exchange (ETDEWEB)

    Marriott, D.L. (Stress Engineering Services, Cincinnati, OH (United States))

    1993-05-01

    This paper explores the value of approximate methods of a specific type, as an efficient aid to performing residual life assessments, particularly when input data are incomplete. These methods, referred to as [open quotes]robust[close quotes] have the desirable attributes of providing satisfactory answers using less-than-perfect input, and being very economical in time of execution. Some examples of robust methods, which have been used successfully in high temperature design and fracture evaluations, are presented. 17 refs., 12 figs.

  20. Prebiotic supplementation and adequate calcium intake have beneficial effects on body mass index changes during early adolescence

    Science.gov (United States)

    Prebiotics have been shown to enhance bone and gastrointestinal health. Recent data suggest a benefit to weight maintenance as well. However, few data are available in children or adolescents. The interactive effects of prebiotic intake and calcium intake on weight maintenance are unknown. Our objec...

  1. How robust is a robust policy? A comparative analysis of alternative robustness metrics for supporting robust decision analysis.

    Science.gov (United States)

    Kwakkel, Jan; Haasnoot, Marjolijn

    2015-04-01

    In response to climate and socio-economic change, in various policy domains there is increasingly a call for robust plans or policies. That is, plans or policies that performs well in a very large range of plausible futures. In the literature, a wide range of alternative robustness metrics can be found. The relative merit of these alternative conceptualizations of robustness has, however, received less attention. Evidently, different robustness metrics can result in different plans or policies being adopted. This paper investigates the consequences of several robustness metrics on decision making, illustrated here by the design of a flood risk management plan. A fictitious case, inspired by a river reach in the Netherlands is used. The performance of this system in terms of casualties, damages, and costs for flood and damage mitigation actions is explored using a time horizon of 100 years, and accounting for uncertainties pertaining to climate change and land use change. A set of candidate policy options is specified up front. This set of options includes dike raising, dike strengthening, creating more space for the river, and flood proof building and evacuation options. The overarching aim is to design an effective flood risk mitigation strategy that is designed from the outset to be adapted over time in response to how the future actually unfolds. To this end, the plan will be based on the dynamic adaptive policy pathway approach (Haasnoot, Kwakkel et al. 2013) being used in the Dutch Delta Program. The policy problem is formulated as a multi-objective robust optimization problem (Kwakkel, Haasnoot et al. 2014). We solve the multi-objective robust optimization problem using several alternative robustness metrics, including both satisficing robustness metrics and regret based robustness metrics. Satisficing robustness metrics focus on the performance of candidate plans across a large ensemble of plausible futures. Regret based robustness metrics compare the

  2. Robust Topology Optimization of Truss with regard to Volume

    CERN Document Server

    Mohr, Daniel P; Matzies, Thomas; Knapek, Christina A

    2011-01-01

    A common problem in the optimization of structures is the handling of uncertainties in the parameters. If the parameters appear in the constraints, the uncertainties can lead to an infinite number of constraints. Usually the constraints have to be approximated by finite expressions to generate a computable problem. Here, using the example of the topology optimization of a truss, a method is proposed to deal with such uncertainties by using robust optimization techniques, leading to an approach without the necessity of any approximation. With adequately chosen load cases, the final expression is equivalent to the multiple load case. Simple numerical examples of typical problems illustrate the application of the method.

  3. Minimal Adequate Model of Unemployment Duration in the Post-Crisis Czech Republic

    Directory of Open Access Journals (Sweden)

    Adam Čabla

    2016-03-01

    Full Text Available Unemployment is one of the leading economic problems in a developed world. The aim of this paper is to identify the differences in unemployment duration in different strata in the post-crisis Czech Republic via building a minimal adequate model, and to quantify the differences. Data from Labour Force Surveys are used and since they are interval censored in nature, proper metodology must be used. The minimal adequate model is built through the accelerated failure time modelling, maximum likelihood estimates and likelihood ratio tests. Variables at the beginning are sex, marital status, age, education, municipality size and number of persons in a household, containing altogether 29 model parameters. The minimal adequate model contains 5 parameters and differences are found between men and women, the youngest category and the rest and the university educated and the rest. The estimated expected values, variances, medians, modes and 90th percentiles are provided for all subgroups.

  4. Imitation of suprasegmental patterns by five-year-old children with adequate and inadequate articulation.

    Science.gov (United States)

    Shadden, B B; Asp, C W; Tonkovich, J D; Mason, D

    1980-08-01

    Ten five-year-old children with adequate articulation skills and 10 five-year-old children with inadequate articulation skills were administered the Templin-Darley Test of Articulation and the Test of Rhythm and Intonation Patterns (TRIP). Differences between the adequate and inadequate groups in terms of the mean percentage correct and the correlations between TRIP and Templin-Darley Test scores within groups were statistically nonsignificant. Item analysis revealed no differences between groups in the pattern of performance on the three subtests of the TRIP or on specific test items. The possible effects of therapy enrollment on suprasegmental test performance are discussed, and future research needs are suggested.

  5. Robust estimation and hypothesis testing

    CERN Document Server

    Tiku, Moti L

    2004-01-01

    In statistical theory and practice, a certain distribution is usually assumed and then optimal solutions sought. Since deviations from an assumed distribution are very common, one cannot feel comfortable with assuming a particular distribution and believing it to be exactly correct. That brings the robustness issue in focus. In this book, we have given statistical procedures which are robust to plausible deviations from an assumed mode. The method of modified maximum likelihood estimation is used in formulating these procedures. The modified maximum likelihood estimators are explicit functions of sample observations and are easy to compute. They are asymptotically fully efficient and are as efficient as the maximum likelihood estimators for small sample sizes. The maximum likelihood estimators have computational problems and are, therefore, elusive. A broad range of topics are covered in this book. Solutions are given which are easy to implement and are efficient. The solutions are also robust to data anomali...

  6. Robust Hitting with Dynamics Shaping

    Science.gov (United States)

    Yashima, Masahito; Yamawaki, Tasuku

    The present paper proposes the trajectory planning based on “the dynamics shaping” for a redundant robotic arm to hit a target robustly toward the desired direction, of which the concept is to shape the robot dynamics appropriately by changing its posture in order to achieve the robust motion. The positional error of the end-effector caused by unknown disturbances converges onto near the singular vector corresponding to its maximum singular value of the output controllability matrix of the robotic arm. Therefore, if we can control the direction of the singular vector by applying the dynamics shaping, we will be able to control the direction of the positional error of the end-effector caused by unknown disturbances. We propose a novel trajectory planning based on the dynamics shaping and verify numerically and experimentally that the robotic arm can robustly hit the target toward the desired direction with a simple open-loop control system even though the disturbance is applied.

  7. Robustness of digital artist authentication

    DEFF Research Database (Denmark)

    Jacobsen, Robert; Nielsen, Morten

    In many cases it is possible to determine the authenticity of a painting from digital reproductions of the paintings; this has been demonstrated for a variety of artists and with different approaches. Common to all these methods in digital artist authentication is that the potential of the method...... is in focus, while the robustness has not been considered, i.e. the degree to which the data collection process influences the decision of the method. However, in order for an authentication method to be successful in practice, it needs to be robust to plausible error sources from the data collection....... In this paper we investigate the robustness of the newly proposed authenticity method introduced by the authors based on second generation multiresolution analysis. This is done by modelling a number of realistic factors that can occur in the data collection....

  8. Advances in robust fractional control

    CERN Document Server

    Padula, Fabrizio

    2015-01-01

    This monograph presents design methodologies for (robust) fractional control systems. It shows the reader how to take advantage of the superior flexibility of fractional control systems compared with integer-order systems in achieving more challenging control requirements. There is a high degree of current interest in fractional systems and fractional control arising from both academia and industry and readers from both milieux are catered to in the text. Different design approaches having in common a trade-off between robustness and performance of the control system are considered explicitly. The text generalizes methodologies, techniques and theoretical results that have been successfully applied in classical (integer) control to the fractional case. The first part of Advances in Robust Fractional Control is the more industrially-oriented. It focuses on the design of fractional controllers for integer processes. In particular, it considers fractional-order proportional-integral-derivative controllers, becau...

  9. Onion structure and network robustness

    CERN Document Server

    Wu, Zhi-Xi; 10.1103/PhysRevE.84.026106

    2011-01-01

    In a recent work [Proc. Natl. Acad. Sci. USA 108, 3838 (2011)], Schneider et al. proposed a new measure for network robustness and investigated optimal networks with respect to this quantity. For networks with a power-law degree distribution, the optimized networks have an onion structure-high-degree vertices forming a core with radially decreasing degrees and an over-representation of edges within the same radial layer. In this paper we relate the onion structure to graphs with good expander properties (another characterization of robust network) and argue that networks of skewed degree distributions with large spectral gaps (and thus good expander properties) are typically onion structured. Furthermore, we propose a generative algorithm producing synthetic scale-free networks with onion structure, circumventing the optimization procedure of Schneider et al. We validate the robustness of our generated networks against malicious attacks and random removals.

  10. Robust Disaster Recovery System Model

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Highly security-critical system should possess features of continuous service. We present a new Robust Disaster Recovery System Model (RDRSM). Through strengthening the ability of safe communications, RDRSM guarantees the secure and reliable command on disaster recovery. Its self-supervision capability can monitor the integrality and security of disaster recovery system itself. By 2D and 3D real-time visible platform provided by GIS, GPS and RS, the model makes the using, management and maintenance of disaster recovery system easier. RDRSM possesses predominant features of security, robustness and controllability. And it can be applied to highly security-critical environments such as E-government and bank. Conducted by RDRSM, an important E-government disaster recovery system has been constructed successfully. The feasibility of this model is verified by practice. We especially emphasize the significance of some components of the model, such as risk assessment, disaster recovery planning, system supervision and robust communication support.

  11. Attractive ellipsoids in robust control

    CERN Document Server

    Poznyak, Alexander; Azhmyakov, Vadim

    2014-01-01

    This monograph introduces a newly developed robust-control design technique for a wide class of continuous-time dynamical systems called the “attractive ellipsoid method.” Along with a coherent introduction to the proposed control design and related topics, the monograph studies nonlinear affine control systems in the presence of uncertainty and presents a constructive and easily implementable control strategy that guarantees certain stability properties. The authors discuss linear-style feedback control synthesis in the context of the above-mentioned systems. The development and physical implementation of high-performance robust-feedback controllers that work in the absence of complete information is addressed, with numerous examples to illustrate how to apply the attractive ellipsoid method to mechanical and electromechanical systems. While theorems are proved systematically, the emphasis is on understanding and applying the theory to real-world situations. Attractive Ellipsoids in Robust Control will a...

  12. Robust Watermarking of Cartographic Images

    Directory of Open Access Journals (Sweden)

    Mauro Barni

    2002-02-01

    Full Text Available We present a method (Text-Based Geometric Normalization—TBGN which, by exploiting the particular content of cartographic images, namely text content, permits to cope with global geometric transformations. First, text is extracted from the to-be-marked map, then text orientation and size are exploited to normalize the image geometry prior to watermark insertion. Watermarking is performed by means of any of the existing algorithms ensuring good robustness against image processing tools. At the decoder side, text is extracted again from the map and used to normalize image geometry. Owing to the robustness of text features with respect to common image manipulations, and to the likely spreading of text all across the digital map, the proposed system exhibits an excellent robustness.

  13. A Robust Enough Virtue Epistemology

    DEFF Research Database (Denmark)

    Broncano-Berrocal, Fernando

    2016-01-01

    What is the nature of knowledge? A popular answer to that long-standing question comes from robust virtue epistemology, whose key idea is that knowing is just a matter of succeeding cognitively—i.e., coming to believe a proposition truly—due to an exercise of cognitive ability. Versions of robust...... virtue epistemology further developing and systematizing this idea offer different accounts of the relation that must hold between an agent’s cognitive success and the exercise of her cognitive abilities as well as of the very nature of those abilities. This paper aims to give a new robust virtue...... epistemological account of knowledge based on a different understanding of the nature and structure of the kind of abilities that give rise to knowledge....

  14. Robust Schur Stability and Robust H^2 Performance

    DEFF Research Database (Denmark)

    Stoustrup, Jakob; Zhao, K.-Y.

    1996-01-01

    In this paper we address the problems of robust stability androbust QTR H^2 performance for uncertain discrete time systemswith nonlinear parametric uncertainties. We consider two families ofsystems with parametric uncertainties described by state space modelswhich offer a fairly general represen...

  15. Asymptotics of robust utility maximization

    CERN Document Server

    Knispel, Thomas

    2012-01-01

    For a stochastic factor model we maximize the long-term growth rate of robust expected power utility with parameter $\\lambda\\in(0,1)$. Using duality methods the problem is reformulated as an infinite time horizon, risk-sensitive control problem. Our results characterize the optimal growth rate, an optimal long-term trading strategy and an asymptotic worst-case model in terms of an ergodic Bellman equation. With these results we propose a duality approach to a "robust large deviations" criterion for optimal long-term investment.

  16. Presymptomatic diagnosis with MRI and adequate treatment ameliorate the outcome after natalizumab-associated progressive multifocal leukoencephalopathy (PML.

    Directory of Open Access Journals (Sweden)

    Hans eLindå

    2013-02-01

    Full Text Available Natalizumab (Tysabri® is a monoclonal antibody that prevents inflammatory cells from binding to brain endothelial cells and passing into the brain parenchyma. Natalizumab is a highly effective treatment for relapsing-remitting multiple sclerosis (MS. Progressive multifocal leukoencephalopathy (PML is an opportunistic brain JC virus infection that has been shown to be associated with natalizumab treatment. We describe PML in a patient with MS after 44 monthly infusions of natalizumab. With the aid of a routine MRI scan, PML was detected before any unambiguous clinical manifestations had emerged. PML was treated with plasma exchange to accelerate removal of natalizumab. Mirtazapine and mefloquine was promptly added and approximately one month after plasma exchange, when an immune-reconstitution-inflammatory-syndrome (IRIS appeared, steroid treatment was initiated. Steroid treatment was then continued until no virus could be detected in the cerebrospinal fluid. The outcome was favourable. We believe that this case clearly illustrates the importance of an early, presymptomatic, detection of PML and an adequate treatment. We also propose that surveillance with MRI scans, every 3 months after 24 months of treatment, should be performed in JC virus antibody positive natalizumab-treated MS patients in order to detect PML in an early phase.

  17. Do sex assault victims receive adequate care? If not, you risk fines, violations.

    Science.gov (United States)

    2002-06-01

    Failure to collect evidence, inadequate care, and delays resulted in a New York City hospital being fined for providing inadequate care to a rape victim. These problems are common in the emergency department. Avoid asking sexual assault victims the same questions repeatedly. Determine the patient's primary concern and address it immediately. Examine patients in a private area with adequate space.

  18. Determinants of prompt and adequate care among presumed malaria cases in a community in eastern Rwanda

    NARCIS (Netherlands)

    Ingabire, Chantal Marie; Kateera, Fredrick; Hakizimana, Emmanuel; Rulisa, Alexis; Muvunyi, Claude; Mens, Petra; Koenraadt, Sander; Mutesa, Leon; Vugt, Van Michele; Borne, Van Den Bart; Alaii, Jane

    2016-01-01

    Background: In order to understand factors influencing fever/malaria management practices among community-based individuals, the study evaluated psychosocial, socio-demographic and environmental determinants of prompt and adequate healthcare-seeking behaviours. Methods: A quantitative household (

  19. Science Education as a Contributor to Adequate Yearly Progress and Accountability Programs

    Science.gov (United States)

    Judson, Eugene

    2010-01-01

    The No Child Left Behind (NCLB) Act requires states to measure the adequate yearly progress (AYP) of each public school and local educational agency (LEA) and to hold schools and LEAs accountable for failing to make AYP. Although it is required that science be assessed in at least three grades, the achievement results from science examinations are…

  20. The Relationship between Parental Involvement and Adequate Yearly Progress among Urban, Suburban, and Rural Schools

    Science.gov (United States)

    Ma, Xin; Shen, Jianping; Krenn, Huilan Y.

    2014-01-01

    Using national data from the 2007-08 School and Staffing Survey, we compared the relationships between parental involvement and school outcomes related to adequate yearly progress (AYP) in urban, suburban, and rural schools. Parent-initiated parental involvement demonstrated significantly positive relationships with both making AYP and staying off…

  1. Evaluating the Reliability of Selected School-Based Indices of Adequate Reading Progress

    Science.gov (United States)

    Wheeler, Courtney E.

    2010-01-01

    The present study examined the stability (i.e., 4-month and 12-month test-retest reliability) of six selected school-based indices of adequate reading progress. The total sampling frame included between 3970 and 5655 schools depending on the index and research question. Each school had at least 40 second-grade students that had complete Oral…

  2. Understanding the pelvic pain mechanism is key to find an adequate therapeutic approach.

    Science.gov (United States)

    Van Kerrebroeck, Philip

    2016-06-25

    Pain is a natural mechanism to actual or potential tissue damage and involves both a sensory and an emotional experience. In chronic pelvic pain, localisation of pain can be widespread and can cause considerable distress. A multidisciplinary approach is needed in order to fully understand the pelvic pain mechanism and to identify an adequate therapeutic approach.

  3. In Search of an Adequate Yet Affordable Tutor in Online Learning Networks

    NARCIS (Netherlands)

    Sloep, Peter; Van Rosmalen, Peter; Kester, Liesbeth; Brouns, Francis; Koper, Rob

    2007-01-01

    Sloep, P. B., Van Rosmalen, P., Kester, L., Brouns, F., & Koper, R. (2006). In Search of an Adequate Yet Affordable Tutor in Online Learning Networks. In Kinshuk, R. Koper, P. Kommers, P. Kirschner, D. G. Sampson & W. Didderen (Eds.), Sixth International Conference on Advanced Learning Technologies

  4. Protecting the Home and Adequate Housing - Living in a Caravan or Trailer as a Human Right

    NARCIS (Netherlands)

    Donders, Y.

    2016-01-01

    Many Roma, gypsies and travellers live in caravans or trailers, sometimes in together trailer parks or camps. This article analyses how this specific lifestyle connected to their housing is protected under the various regimes and provisions of international human rights law. Home and adequate housin

  5. 9 CFR 2.40 - Attending veterinarian and adequate veterinary care (dealers and exhibitors).

    Science.gov (United States)

    2010-01-01

    ... veterinary care (dealers and exhibitors). 2.40 Section 2.40 Animals and Animal Products ANIMAL AND PLANT... veterinary care to its animals in compliance with this section. (1) Each dealer and exhibitor shall employ an... adequate veterinary care and to oversee the adequacy of other aspects of animal care and use. (b)...

  6. 76 FR 51041 - Hemoglobin Standards and Maintaining Adequate Iron Stores in Blood Donors; Public Workshop

    Science.gov (United States)

    2011-08-17

    ... HUMAN SERVICES Food and Drug Administration Hemoglobin Standards and Maintaining Adequate Iron Stores in... workshop. The Food and Drug Administration (FDA) is announcing a public workshop entitled: ``Hemoglobin... discuss blood donor hemoglobin and hematocrit qualification standards in the United States, its impact...

  7. The Unequal Effect of Adequate Yearly Progress: Evidence from School Visits

    Science.gov (United States)

    Brown, Abigail B.; Clift, Jack W.

    2010-01-01

    The authors report insights, based on annual site visits to elementary and middle schools in three states from 2004 to 2006, into the incentive effect of the No Child Left Behind Act's requirement that increasing percentages of students make Adequate Yearly Progress (AYP) in every public school. They develop a framework, drawing on the physics…

  8. 21 CFR 514.117 - Adequate and well-controlled studies.

    Science.gov (United States)

    2010-04-01

    ... of the Center for Veterinary Medicine (the Director) may, on the Director's own initiative or on the... adequate and well-controlled studies of a new animal drug is to distinguish the effect of the new animal drug from other influences, such as spontaneous change in the course of the disease, normal...

  9. Use of Linear Programming to Develop Cost-Efficient Minimized Nutritionally Adequate Health Promoting Food Baskets

    DEFF Research Database (Denmark)

    Parlesak, Alexandr; Tetens, Inge; Jensen, Jørgen Dejgård;

    2016-01-01

    using linear programming. The FBs were defined depending on the type of constraints applied: cultural acceptability (C), or dietary guidelines (D), or nutrient recommendations (N), or cultural acceptability and nutrient recommendations (CN), or dietary guidelines and nutrient recommendations (DN......: Use of linear programming facilitates the generation of low-cost food baskets that are nutritionally adequate, health promoting, and culturally acceptable....

  10. Does the new conceptual framework provide adequate concepts for reporting relevant information about performance?

    NARCIS (Netherlands)

    Brouwer, A.; Faramarzi, A; Hoogendoorn, M.

    2014-01-01

    The basic question we raise in this paper is whether the 2013 Discussion Paper (DP 2013) on the Conceptual Framework provides adequate principles for reporting an entity’s performance and what improvements could be made in light of both user needs and evidence from academic literature. DP 2013 propo

  11. A robust adaptive robot controller

    NARCIS (Netherlands)

    Berghuis, Harry; Ortega, Romeo; Nijmeijer, Henk

    1993-01-01

    A globally convergent adaptive control scheme for robot motion control with the following features is proposed. First, the adaptation law possesses enhanced robustness with respect to noisy velocity measurements. Second, the controller does not require the inclusion of high gain loops that may excit

  12. Hints for practical robust optimization

    NARCIS (Netherlands)

    Gorissen, B.L.; Yanikoglu, I.; den Hertog, D.

    2013-01-01

    Robust optimization (RO) is a young and active research field that has been mainly developed in the last 15 years. RO techniques are very useful for practice and not difficult to understand for practitioners. It is therefore remarkable that real-life applications of RO are still lagging behind; ther

  13. Mental Models: A Robust Definition

    Science.gov (United States)

    Rook, Laura

    2013-01-01

    Purpose: The concept of a mental model has been described by theorists from diverse disciplines. The purpose of this paper is to offer a robust definition of an individual mental model for use in organisational management. Design/methodology/approach: The approach adopted involves an interdisciplinary literature review of disciplines, including…

  14. Robust Simulations and Significant Separations

    CERN Document Server

    Fortnow, Lance

    2010-01-01

    We define and study a new notion of "robust simulations" between complexity classes which is intermediate between the traditional notions of infinitely-often and almost-everywhere, as well as a corresponding notion of "significant separations". A language L has a robust simulation in a complexity class C if there is a language in C which agrees with L on arbitrarily large polynomial stretches of input lengths. There is a significant separation of L from C if there is no robust simulation of L in C. The new notion of simulation is a cleaner and more natural notion of simulation than the infinitely-often notion. We show that various implications in complexity theory such as the collapse of PH if NP = P and the Karp-Lipton theorem have analogues for robust simulations. We then use these results to prove that most known separations in complexity theory, such as hierarchy theorems, fixed polynomial circuit lower bounds, time-space tradeoffs, and the theorems of Allender and Williams, can be strengthened to signifi...

  15. Robust control design with MATLAB

    CERN Document Server

    Gu, Da-Wei; Konstantinov, Mihail M

    2013-01-01

    Robust Control Design with MATLAB® (second edition) helps the student to learn how to use well-developed advanced robust control design methods in practical cases. To this end, several realistic control design examples from teaching-laboratory experiments, such as a two-wheeled, self-balancing robot, to complex systems like a flexible-link manipulator are given detailed presentation. All of these exercises are conducted using MATLAB® Robust Control Toolbox 3, Control System Toolbox and Simulink®. By sharing their experiences in industrial cases with minimum recourse to complicated theories and formulae, the authors convey essential ideas and useful insights into robust industrial control systems design using major H-infinity optimization and related methods allowing readers quickly to move on with their own challenges. The hands-on tutorial style of this text rests on an abundance of examples and features for the second edition: ·        rewritten and simplified presentation of theoretical and meth...

  16. Theoretical Framework for Robustness Evaluation

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2011-01-01

    This paper presents a theoretical framework for evaluation of robustness of structural systems, incl. bridges and buildings. Typically modern structural design codes require that ‘the consequence of damages to structures should not be disproportional to the causes of the damages’. However, althou...

  17. Robust power system frequency control

    CERN Document Server

    Bevrani, Hassan

    2008-01-01

    Emphasizes the physical and engineering aspects of the power system frequency control design problem while providing a conceptual understanding of frequency regulation and application of robust control techniques. This book summarizes the author's research outcomes, contributions and experiences with power system frequency regulation.

  18. Robust dual-response optimization

    NARCIS (Netherlands)

    Yanikoglu, Ihsan; den Hertog, Dick; Kleijnen, J.P.C.

    2016-01-01

    This article presents a robust optimization reformulation of the dual-response problem developed in response surface methodology. The dual-response approach fits separate models for the mean and the variance and analyzes these two models in a mathematical optimization setting. We use metamodels esti

  19. Calculation of the Cost of an Adequate Education in Kentucky: A Professional Judgment Approach

    Directory of Open Access Journals (Sweden)

    Deborah A. Verstegen

    2004-02-01

    Full Text Available What is an adequate education and how much does it cost? In 1989, Kentucky’s State Supreme Court found the entire system of education unconstitutional-“all of its parts and parcels”. The Court called for all children to have access to an adequate education, one that is uniform and has as its goal the development of seven capacities, including: (i “sufficient oral and written communication skills to enable students to function in a complex and rapidly changing civilization . . . .and (vii sufficient levels of academic or vocational skills to enable public school students to compete favorably with their counterparts in surrounding states, in academics or in the job market”. Now, over a decade later, key questions remain regarding whether these objectives have been fulfilled. This research is designed to calculate the cost of an adequate education by aligning resources to State standards, laws and objectives, using a professional judgment approach. Seven focus groups were convened for this purpose and the scholarly literature was reviewed to provide multiple inputs into study findings. The study produced a per pupil base cost for each of three prototype school districts and an total statewide cost, with the funding gap between existing revenue and the revenue needed for current operations of $1.097 billion per year (2001-02. Additional key resource requirements needed to achieve an adequate education, identified by professional judgment panels, include: (1 extending the school year for students and teachers, (2 adding voluntary half-day preschool for three and four year olds, and (3 raising teacher salaries. This increases the funding gap to $1.23 billion and suggests that significant new funding is required over time if the Commonwealth of Kentucky is to provide an adequate and equitable education of high quality for all children and youth as directed by the State Supreme Court.

  20. Robust Reliability or reliable robustness? - Integrated consideration of robustness and reliability aspects

    DEFF Research Database (Denmark)

    Kemmler, S.; Eifler, Tobias; Bertsche, B.

    2015-01-01

    products are and vice versa. For a comprehensive understanding and to use existing synergies between both domains, this paper discusses the basic principles of Reliability- and Robust Design theory. The development of a comprehensive model will enable an integrated consideration of both domains...

  1. Use of Linear Programming to Develop Cost-Efficient Minimized Nutritionally Adequate Health Promoting Food Baskets

    DEFF Research Database (Denmark)

    Parlesak, Alexandr; Tetens, Inge; Jensen, Jørgen Dejgård

    2016-01-01

    Background: Food-Based Dietary Guidelines (FBDGs) are developed to promote healthier eating patterns, but increasing food prices may make healthy eating less affordable. The aim of this study was to design a range of cost-minimized nutritionally adequate health-promoting food baskets (FBs......) that help prevent both micronutrient inadequacy and diet-related non-communicable diseases at lowest cost. Methods: Average prices for 312 foods were collected within the Greater Copenhagen area. The cost and nutrient content of five different cost-minimized FBs for a family of four were calculated per day......: Use of linear programming facilitates the generation of low-cost food baskets that are nutritionally adequate, health promoting, and culturally acceptable....

  2. Use of Linear Programming to Develop Cost-Minimized Nutritionally Adequate Health Promoting Food Baskets

    DEFF Research Database (Denmark)

    Parlesak, A.; Tetens, Inge; Dejgård Jensen, Jørgen;

    2016-01-01

    Food-Based Dietary Guidelines (FBDGs) are developed to promote healthier eating patterns, but increasing food prices may make healthy eating less affordable. The aim of this study was to design a range of cost-minimized nutritionally adequate health-promoting food baskets (FBs) that help prevent...... facilitates the generation of low-cost food baskets that are nutritionally adequate, health promoting, and culturally acceptable....... both micronutrient inadequacy and diet-related non-communicable diseases at lowest cost. Average prices for 312 foods were collected within the Greater Copenhagen area. The cost and nutrient content of five different cost-minimized FBs for a family of four were calculated per day using linear...

  3. Which Food Security Determinants Predict Adequate Vegetable Consumption among Rural Western Australian Children?

    Directory of Open Access Journals (Sweden)

    Stephanie L. Godrich

    2017-01-01

    Full Text Available Improving the suboptimal vegetable consumption among the majority of Australian children is imperative in reducing chronic disease risk. The objective of this research was to determine whether there was a relationship between food security determinants (FSD (i.e., food availability, access, and utilisation dimensions and adequate vegetable consumption among children living in regional and remote Western Australia (WA. Caregiver-child dyads (n = 256 living in non-metropolitan/rural WA completed cross-sectional surveys that included questions on FSD, demographics and usual vegetable intake. A total of 187 dyads were included in analyses, which included descriptive and logistic regression analyses via IBM SPSS (version 23. A total of 13.4% of children in this sample had adequate vegetable intake. FSD that met inclusion criteria (p ≤ 0.20 for multivariable regression analyses included price; promotion; quality; location of food outlets; variety of vegetable types; financial resources; and transport to outlets. After adjustment for potential demographic confounders, the FSD that predicted adequate vegetable consumption were, variety of vegetable types consumed (p = 0.007, promotion (p = 0.017, location of food outlets (p = 0.027, and price (p = 0.043. Food retail outlets should ensure that adequate varieties of vegetable types (i.e., fresh, frozen, tinned are available, vegetable messages should be promoted through food retail outlets and in community settings, towns should include a range of vegetable purchasing options, increase their reliance on a local food supply and increase transport options to enable affordable vegetable purchasing.

  4. Evaluation of lymph node numbers for adequate staging of Stage II and III colon cancer

    Directory of Open Access Journals (Sweden)

    Bumpers Harvey L

    2011-05-01

    Full Text Available Abstract Background Although evaluation of at least 12 lymph nodes (LNs is recommended as the minimum number of nodes required for accurate staging of colon cancer patients, there is disagreement on what constitutes an adequate identification of such LNs. Methods To evaluate the minimum number of LNs for adequate staging of Stage II and III colon cancer, 490 patients were categorized into groups based on 1-6, 7-11, 12-19, and ≥ 20 LNs collected. Results For patients with Stage II or III disease, examination of 12 LNs was not significantly associated with recurrence or mortality. For Stage II (HR = 0.33; 95% CI, 0.12-0.91, but not for Stage III patients (HR = 1.59; 95% CI, 0.54-4.64, examination of ≥20 LNs was associated with a reduced risk of recurrence within 2 years. However, examination of ≥20 LNs had a 55% (Stage II, HR = 0.45; 95% CI, 0.23-0.87 and a 31% (Stage III, HR = 0.69; 95% CI, 0.38-1.26 decreased risk of mortality, respectively. For each six additional LNs examined from Stage III patients, there was a 19% increased probability of finding a positive LN (parameter estimate = 0.18510, p Conclusions Thus, the 12 LN cut-off point cannot be supported as requisite in determining adequate staging of colon cancer based on current data. However, a minimum of 6 LNs should be examined for adequate staging of Stage II and III colon cancer patients.

  5. Effective dose of dexmedetomidine to induce adequate sedation in elderly patients under spinal anesthesia

    OpenAIRE

    2015-01-01

    Background During sedation with dexmedetomidine, a dose adjustment may be needed based on the invasiveness of the procedure, the patient's general condition, and their age. We aim here to determine the effective dose (ED) of dexmedetomidine to induce an adequate depth of sedation in elderly patients undergoing spinal anesthesia. Methods In this study, 47 patients aged 65 years or older, American Society of Anesthesiologists physical status I or II, undergoing spinal anesthesia were included. ...

  6. Algebraic connectivity and graph robustness.

    Energy Technology Data Exchange (ETDEWEB)

    Feddema, John Todd; Byrne, Raymond Harry; Abdallah, Chaouki T. (University of New Mexico)

    2009-07-01

    Recent papers have used Fiedler's definition of algebraic connectivity to show that network robustness, as measured by node-connectivity and edge-connectivity, can be increased by increasing the algebraic connectivity of the network. By the definition of algebraic connectivity, the second smallest eigenvalue of the graph Laplacian is a lower bound on the node-connectivity. In this paper we show that for circular random lattice graphs and mesh graphs algebraic connectivity is a conservative lower bound, and that increases in algebraic connectivity actually correspond to a decrease in node-connectivity. This means that the networks are actually less robust with respect to node-connectivity as the algebraic connectivity increases. However, an increase in algebraic connectivity seems to correlate well with a decrease in the characteristic path length of these networks - which would result in quicker communication through the network. Applications of these results are then discussed for perimeter security.

  7. System Identification and Robust Control

    DEFF Research Database (Denmark)

    Tøffner-Clausen, S.

    for mixed real and complex perturbation sets. A novel method, denoted m - K iteration, has been develop to solve the mixed m problem. A general feature of all robust control design methods is the need for specifying not only a nominal model but also some kind of quantification of the uncertainty is, however......, a non-trivial problem which to some extent has been neglected by the theoreticians of robust control. An uncertainty specification has simply been assumed given. One way of obtaining a perturbation model is by physical modelling. Application if the fundamental laws of thermodynamics, mechanics, physics...... estimate frequency domain uncertainty estimates may be obtained. In classical (i.e. Ljungian) system identification, model quality has been assessed under the structure of the model is assumed to be correct. This is, however, often an inadequate assumption in connection with control design. Recently...

  8. A Robust Streaming Media System

    Science.gov (United States)

    Youwei, Zhang

    Presently, application layer multicast protocols (ALM) are proposed as substitute for IP multicast and have made extraordinary achievements. Integrated with Multi-data-stream mode such as Multiple Description Coding (MDC), ALM becomes more scalable and robust in high-dynamic Internet environment compared with single data stream. Although MDC can provide a flexible data transmission style, the synchronization of different descriptions encoded from one video source is proved to be difficult due to different delay on diverse transmission paths. In this paper, an ALM system called HMDC is proposed to improve accepted video quality of streaming media, hosts can join the separate overlay trees in different layers simultaneously, then the maximum synchronized descriptions of the same layer are worked out to acquire the best video quality. Simulations implemented on Internet-like topology indicate that HMDC achieves better video quality, lower link stress, higher robustness and comparable latency compared with traditional ALM protocols.

  9. Robust nonlinear regression in applications

    OpenAIRE

    Lim, Changwon; Sen, Pranab K.; Peddada, Shyamal D.

    2013-01-01

    Robust statistical methods, such as M-estimators, are needed for nonlinear regression models because of the presence of outliers/influential observations and heteroscedasticity. Outliers and influential observations are commonly observed in many applications, especially in toxicology and agricultural experiments. For example, dose response studies, which are routinely conducted in toxicology and agriculture, sometimes result in potential outliers, especially in the high dose gr...

  10. A robust adaptive robot controller

    OpenAIRE

    1993-01-01

    A globally convergent adaptive control scheme for robot motion control with the following features is proposed. First, the adaptation law possesses enhanced robustness with respect to noisy velocity measurements. Second, the controller does not require the inclusion of high gain loops that may excite the unmodeled dynamics and amplify the noise level. Third, we derive for the unknown parameter design a relationship between compensator gains and closed-loop convergence rates that is independen...

  11. Robust estimation of Cronbach's alpha

    OpenAIRE

    2002-01-01

    Cronbach’s alpha is a popular method to measure reliability, e.g. in quantifying the reliability of a score to summarize the information of several items in questionnaires. The alpha coefficient is known to be non-robust. We study the behavior of this coefficient in different settings to identify situations, which can easily occur in practice, but under which the Cronbach’s alpha coefficient is extremely sensitive to violations of the classical model assumptions. Furthermore, we construct a r...

  12. Robust power system frequency control

    CERN Document Server

    Bevrani, Hassan

    2014-01-01

    This updated edition of the industry standard reference on power system frequency control provides practical, systematic and flexible algorithms for regulating load frequency, offering new solutions to the technical challenges introduced by the escalating role of distributed generation and renewable energy sources in smart electric grids. The author emphasizes the physical constraints and practical engineering issues related to frequency in a deregulated environment, while fostering a conceptual understanding of frequency regulation and robust control techniques. The resulting control strategi

  13. Global risk assessment of aflatoxins in maize and peanuts: are regulatory standards adequately protective?

    Science.gov (United States)

    Wu, Felicia; Stacy, Shaina L; Kensler, Thomas W

    2013-09-01

    The aflatoxins are a group of fungal metabolites that contaminate a variety of staple crops, including maize and peanuts, and cause an array of acute and chronic human health effects. Aflatoxin B1 in particular is a potent liver carcinogen, and hepatocellular carcinoma (HCC) risk is multiplicatively higher for individuals exposed to both aflatoxin and chronic infection with hepatitis B virus (HBV). In this work, we sought to answer the question: do current aflatoxin regulatory standards around the world adequately protect human health? Depending upon the level of protection desired, the answer to this question varies. Currently, most nations have a maximum tolerable level of total aflatoxins in maize and peanuts ranging from 4 to 20ng/g. If the level of protection desired is that aflatoxin exposures would not increase lifetime HCC risk by more than 1 in 100,000 cases in the population, then most current regulatory standards are not adequately protective even if enforced, especially in low-income countries where large amounts of maize and peanuts are consumed and HBV prevalence is high. At the protection level of 1 in 10,000 lifetime HCC cases in the population, however, almost all aflatoxin regulations worldwide are adequately protective, with the exception of several nations in Africa and Latin America.

  14. A test for adequate wastewater treatment based on glutathione S transferase isoenzyme profile.

    Science.gov (United States)

    Grammou, A; Samaras, P; Papadimitriou, C; Papadopoulos, A I

    2013-04-01

    Discharge to the environment of treated or non-treated municipal wastewater imposes several threats to coastal and estuarine ecosystems which are difficult to assess. In our study we evaluate the use of the isoenzyme profile of glutathione S transferase (GST) in combination with the kinetic characteristics of the whole enzyme and of heme peroxidase, as a test of adequate treatment of municipal wastewater. For this reason, Artemia nauplii were incubated in artificial seawater prepared by wastewater samples, such as secondary municipal effluents produced by a conventional activated sludge unit and advanced treated effluents produced by the employment of coagulation, activated carbon adsorption and chlorination as single processes or as combined ones. Characteristic changes of the isoenzyme pattern and the enzymes' kinetic properties were caused by chlorinated secondary municipal effluent or by secondary non-chlorinated effluent. Advanced treatment by combination of coagulation and/or carbon adsorption resulted to less prominent changes, suggesting more adequate treatment. Our results suggest that GST isoenzyme profile in combination with the kinetic properties of the total enzyme family is a sensitive test for the evaluation of the adequateness of the treatment of reclaimed wastewater and the reduction of potentially harmful compounds. Potentially, it may offer a 'fingerprint' characteristic of a particular effluent and probably of the treatment level it has been subjected.

  15. Current strategies for the restoration of adequate lordosis during lumbar fusion.

    Science.gov (United States)

    Barrey, Cédric; Darnis, Alice

    2015-01-18

    Not restoring the adequate lumbar lordosis during lumbar fusion surgery may result in mechanical low back pain, sagittal unbalance and adjacent segment degeneration. The objective of this work is to describe the current strategies and concepts for restoration of adequate lordosis during fusion surgery. Theoretical lordosis can be evaluated from the measurement of the pelvic incidence and from the analysis of spatial organization of the lumbar spine with 2/3 of the lordosis given by the L4-S1 segment and 85% by the L3-S1 segment. Technical aspects involve patient positioning on the operating table, release maneuvers, type of instrumentation used (rod, screw-rod connection, interbody cages), surgical sequence and the overall surgical strategy. Spinal osteotomies may be required in case of fixed kyphotic spine. AP combined surgery is particularly efficient in restoring lordosis at L5-S1 level and should be recommended. Finally, not one but several strategies may be used to achieve the need for restoration of adequate lordosis during fusion surgery.

  16. Trading Robustness Requirements in Mars Entry Trajectory Design

    Science.gov (United States)

    Lafleur, Jarret M.

    2009-01-01

    One of the most important metrics characterizing an atmospheric entry trajectory in preliminary design is the size of its predicted landing ellipse. Often, requirements for this ellipse are set early in design and significantly influence both the expected scientific return from a particular mission and the cost of development. Requirements typically specify a certain probability level (6-level) for the prescribed ellipse, and frequently this latter requirement is taken at 36. However, searches for the justification of 36 as a robustness requirement suggest it is an empirical rule of thumb borrowed from non-aerospace fields. This paper presents an investigation into the sensitivity of trajectory performance to varying robustness (6-level) requirements. The treatment of robustness as a distinct objective is discussed, and an analysis framework is presented involving the manipulation of design variables to effect trades between performance and robustness objectives. The scenario for which this method is illustrated is the ballistic entry of an MSL-class Mars entry vehicle. Here, the design variable is entry flight path angle, and objectives are parachute deploy altitude performance and error ellipse robustness. Resulting plots show the sensitivities between these objectives and trends in the entry flight path angles required to design to these objectives. Relevance to the trajectory designer is discussed, as are potential steps for further development and use of this type of analysis.

  17. Robustness Analysis of Timber Truss Structure

    DEFF Research Database (Denmark)

    Rajčić, Vlatka; Čizmar, Dean; Kirkegaard, Poul Henning

    2010-01-01

    The present paper discusses robustness of structures in general and the robustness requirements given in the codes. Robustness of timber structures is also an issues as this is closely related to Working group 3 (Robustness of systems) of the COST E55 project. Finally, an example of a robustness...... evaluation of a widespan timber truss structure is presented. This structure was built few years ago near Zagreb and has a span of 45m. Reliability analysis of the main members and the system is conducted and based on this a robustness analysis is preformed....

  18. Robustness in Railway Operations (RobustRailS)

    DEFF Research Database (Denmark)

    Jensen, Jens Parbo; Nielsen, Otto Anker

    This study considers the problem of enhancing railway timetable robustness without adding slack time, hence increasing the travel time. The approach integrates a transit assignment model to assess how passengers adapt their behaviour whenever operations are changed. First, the approach considers...... the existing stopping patterns of the railway lines. Then, based on the passenger demand we try to optimize the overall utility by changing the stopping pattern in a way that capacity utilization is reduced without affecting the frequency of the train lines nor increasing the passengers’ travel time....

  19. Progressive refinement for robust image registration

    Institute of Scientific and Technical Information of China (English)

    Li Song; Yuanhua Zhou; Jun Zhou

    2005-01-01

    @@ A new image registration algorithm with robust cost function and progressive refinement estimation is developed on the basis of direct method (DM). The robustness lies in M-estimation to avert larger local noise and outliers.

  20. Are the current Australian sun exposure guidelines effective in maintaining adequate levels of 25-hydroxyvitamin D?

    Science.gov (United States)

    Kimlin, Michael; Sun, Jiandong; Sinclair, Craig; Heward, Sue; Hill, Jane; Dunstone, Kimberley; Brodie, Alison

    2016-01-01

    An adequate vitamin D status, as measured by serum 25-hydroxyvitamin D (25(OH)D) concentration, is important in humans for maintenance of healthy bones and muscle function. Serum 25(OH)D concentration was assessed in participants from Melbourne, Australia (37.81S, 144.96E), who were provided with the current Australian guidelines on sun exposure for 25(OH)D adequacy (25(OH)D ≥50 nmol/L). Participants were interviewed in February (summer, n=104) and August (winter, n=99) of 2013. Serum 25(OH)D concentration was examined as a function of measures of sun exposure and sun protection habits with control of key characteristics such as dietary intake of vitamin D, body mass index (BMI) and skin colour, that may modify this relationship. The mean 25(OH)D concentration in participants who complied with the current sun exposure guidelines was 67.3 nmol/L in summer and 41.9 nmol/L in winter. At the end of the study, 69.3% of participants who complied with the summer sun exposure guidelines were 25(OH)D adequate, while only 27.6% of participants who complied with the winter sun exposure guidelines were 25(OH)D adequate at the end of the study. The results suggest that the current Australian guidelines for sun exposure for 25(OH)D adequacy are effective for most in summer and ineffective for most in winter. This article is part of a Special Issue entitled '17th Vitamin D Workshop'.

  1. The Nigerian health care system: Need for integrating adequate medical intelligence and surveillance systems

    Directory of Open Access Journals (Sweden)

    Menizibeya Osain Welcome

    2011-01-01

    Full Text Available Objectives : As an important element of national security, public health not only functions to provide adequate and timely medical care but also track, monitor, and control disease outbreak. The Nigerian health care had suffered several infectious disease outbreaks year after year. Hence, there is need to tackle the problem. This study aims to review the state of the Nigerian health care system and to provide possible recommendations to the worsening state of health care in the country. To give up-to-date recommendations for the Nigerian health care system, this study also aims at reviewing the dynamics of health care in the United States, Britain, and Europe with regards to methods of medical intelligence/surveillance. Materials and Methods : Databases were searched for relevant literatures using the following keywords: Nigerian health care, Nigerian health care system, and Nigerian primary health care system. Additional keywords used in the search were as follows: United States (OR Europe health care dynamics, Medical Intelligence, Medical Intelligence systems, Public health surveillance systems, Nigerian medical intelligence, Nigerian surveillance systems, and Nigerian health information system. Literatures were searched in scientific databases Pubmed and African Journals OnLine. Internet searches were based on Google and Search Nigeria. Results : Medical intelligence and surveillance represent a very useful component in the health care system and control diseases outbreak, bioattack, etc. There is increasing role of automated-based medical intelligence and surveillance systems, in addition to the traditional manual pattern of document retrieval in advanced medical setting such as those in western and European countries. Conclusion : The Nigerian health care system is poorly developed. No adequate and functional surveillance systems are developed. To achieve success in health care in this modern era, a system well grounded in routine

  2. Adequate Iodine Status in New Zealand School Children Post-Fortification of Bread with Iodised Salt

    Science.gov (United States)

    Jones, Emma; McLean, Rachael; Davies, Briar; Hawkins, Rochelle; Meiklejohn, Eva; Ma, Zheng Feei; Skeaff, Sheila

    2016-01-01

    Iodine deficiency re-emerged in New Zealand in the 1990s, prompting the mandatory fortification of bread with iodised salt from 2009. This study aimed to determine the iodine status of New Zealand children when the fortification of bread was well established. A cross-sectional survey of children aged 8–10 years was conducted in the cities of Auckland and Christchurch, New Zealand, from March to May 2015. Children provided a spot urine sample for the determination of urinary iodine concentration (UIC), a fingerpick blood sample for Thyroglobulin (Tg) concentration, and completed a questionnaire ascertaining socio-demographic information that also included an iodine-specific food frequency questionnaire (FFQ). The FFQ was used to estimate iodine intake from all main food sources including bread and iodised salt. The median UIC for all children (n = 415) was 116 μg/L (females 106 μg/L, males 131 μg/L) indicative of adequate iodine status according to the World Health Organisation (WHO, i.e., median UIC of 100–199 μg/L). The median Tg concentration was 8.7 μg/L, which was <10 μg/L confirming adequate iodine status. There was a significant difference in UIC by sex (p = 0.001) and ethnicity (p = 0.006). The mean iodine intake from the food-only model was 65 μg/day. Bread contributed 51% of total iodine intake in the food-only model, providing a mean iodine intake of 35 μg/day. The mean iodine intake from the food-plus-iodised salt model was 101 μg/day. In conclusion, the results of this study confirm that the iodine status in New Zealand school children is now adequate. PMID:27196925

  3. Adequate Iodine Status in New Zealand School Children Post-Fortification of Bread with Iodised Salt

    Directory of Open Access Journals (Sweden)

    Emma Jones

    2016-05-01

    Full Text Available Iodine deficiency re-emerged in New Zealand in the 1990s, prompting the mandatory fortification of bread with iodised salt from 2009. This study aimed to determine the iodine status of New Zealand children when the fortification of bread was well established. A cross-sectional survey of children aged 8–10 years was conducted in the cities of Auckland and Christchurch, New Zealand, from March to May 2015. Children provided a spot urine sample for the determination of urinary iodine concentration (UIC, a fingerpick blood sample for Thyroglobulin (Tg concentration, and completed a questionnaire ascertaining socio-demographic information that also included an iodine-specific food frequency questionnaire (FFQ. The FFQ was used to estimate iodine intake from all main food sources including bread and iodised salt. The median UIC for all children (n = 415 was 116 μg/L (females 106 μg/L, males 131 μg/L indicative of adequate iodine status according to the World Health Organisation (WHO, i.e., median UIC of 100–199 μg/L. The median Tg concentration was 8.7 μg/L, which was <10 μg/L confirming adequate iodine status. There was a significant difference in UIC by sex (p = 0.001 and ethnicity (p = 0.006. The mean iodine intake from the food-only model was 65 μg/day. Bread contributed 51% of total iodine intake in the food-only model, providing a mean iodine intake of 35 μg/day. The mean iodine intake from the food-plus-iodised salt model was 101 μg/day. In conclusion, the results of this study confirm that the iodine status in New Zealand school children is now adequate.

  4. Robust Proportional Integral Control of Water Level in an Irrigation Main Canal

    Directory of Open Access Journals (Sweden)

    Ybrain Hernández López

    2015-07-01

    Full Text Available Nowadays In this paper, the design of a robust PI controller for effective level control in the second poolof the irrigation main canal Güira de Melena is developed. A mathematical model that adequately describesthe dynamic behavior of the plant under study is obtained from system identification procedure.This model is characterized by its simplicity (first order with time delay. The robustness analysis of thedesigned PI controller vs parametric variations of the obtained mathematical model showed satisfactoryresults, and therefore the implementation of this controller is validated.

  5. Robust Adaptive Quantum Phase Estimation

    CERN Document Server

    Roy, Shibdas; Huntington, Elanor H

    2014-01-01

    Quantum parameter estimation is central to many fields such as quantum computation, communications and metrology. Optimal estimation theory has been instrumental in achieving the best accuracy in quantum parameter estimation, which is possible when we have very precise knowledge of and control over the model. However, uncertainties in key parameters underlying the system are unavoidable and may impact the quality of the estimate. We show here how quantum optical phase estimation of a squeezed state of light exhibits improvement when using a robust fixed-interval smoother designed with uncertainties explicitly introduced in parameters underlying the phase noise.

  6. Sustainable Resilient, Robust & Resplendent Enterprises

    DEFF Research Database (Denmark)

    Edgeman, Rick

    . Resilience may be regarded as enterprise ability to recover or rebound from negative shocks or extreme challenges to its ecosystem (Contu, 2002). Robustness, in contrast to resilience, is not so much enterprise ability to recover from shocks or challenges to its ecosystem, but rather resistance or immunity...... to their impact. Resplendent enterprises are introduced with resplendence referring not to some sort of public or private façade, but instead refers to organizations marked by dual brilliance and nobility of strategy, governance and comportment that yields superior and sustainable triple bottom line performance...

  7. Enucleation for gastrointestinal stromal tumors at the esophagogastric junction: Is this an adequate solution?

    Institute of Scientific and Technical Information of China (English)

    Nadia Peparini; Giovanni Carbotta; Piero Chirletti

    2011-01-01

    The authors discussed the proposal by Coccolini and colleagues to treat gastrointestinal stromal tumors (GISTs) at the esophagogastric junction with enucleation and, if indicated, adjuvant therapy, reducing the risks related to esophageal and gastroesophageal resection. They concluded that, because the prognostic impact of a T1 high-mitotic rate on esophageal GIST is worse than that of a T1 high-mitotic rate on gastric GIST, enucleation may not be an adequate surgery for esophagogastric GISTs with a high mitotic rate in which the guarantee of negative resection margins and adjuvant therapies can be the only chance of survival.

  8. Adequate X-ray control of central and peripheral vena cava catheters

    Energy Technology Data Exchange (ETDEWEB)

    Bostel, F.; Schmidt, C.

    1985-06-01

    Central venous catheters are frequently used not only in intensive care patients. Attention is drawn to the possible displacements of catheters and to the need for correct radiological control of the catheter position. Since unrecognized extravascular position of the catheter is followed by serious complications s.e. tension pneumothorax and infusions into the pleural cavity or the mediastinum, adequate X-ray control has to be carried out with simultaneous administration of contrast medium. Correction of displaced catheters should be done under fluoroscopy.

  9. Robust portfolio selection under norm uncertainty

    Directory of Open Access Journals (Sweden)

    Lei Wang

    2016-06-01

    Full Text Available Abstract In this paper, we consider the robust portfolio selection problem which has a data uncertainty described by the ( p , w $(p,w$ -norm in the objective function. We show that the robust formulation of this problem is equivalent to a linear optimization problem. Moreover, we present some numerical results concerning our robust portfolio selection problem.

  10. Robust synchronization of uncertain chaotic systems

    Institute of Scientific and Technical Information of China (English)

    Li Fang; Hu Ai-Hua; Xu Zheng-Yuan

    2006-01-01

    This paper investigates robust unified (lag, anticipated, and complete) synchronization of two coupled chaotic systems. By introducing the concepts of positive definite symmetrical matrix and Riccati inequality and the theory of robust stability, several criteria on robust synchronization are established. Extensive numerical simulations are also used to confirm the results.

  11. Methodology in robust and nonparametric statistics

    CERN Document Server

    Jurecková, Jana; Picek, Jan

    2012-01-01

    Introduction and SynopsisIntroductionSynopsisPreliminariesIntroductionInference in Linear ModelsRobustness ConceptsRobust and Minimax Estimation of LocationClippings from Probability and Asymptotic TheoryProblemsRobust Estimation of Location and RegressionIntroductionM-EstimatorsL-EstimatorsR-EstimatorsMinimum Distance and Pitman EstimatorsDifferentiable Statistical FunctionsProblemsAsymptotic Representations for L-Estimators

  12. A ROBUST OPTICAL FLOW COMPUTATION

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This paper presents a new method for robust and accurate optical flow estimation. The significance of this work is twofold. Firstly, the idea of bi-directional scheme is adopted to reduce the model error of optical flow equation, which allows the second order Taylor's expansion of optical flow equation for accurate solution without much extra computational burden; Secondly, this paper establishs a new optical flow equation based on LSCM (Local Structure Constancy Model) instead of BCM (Brightness Constancy Model), namely the optical flow equation does not act on scalar but on tensor-valued (matrix-valued) field, due to the two reason: (1) structure tensor-value contains local spatial structure information, which provides us more useable cues for computation than scalar; (2) local image structure is less sensitive to illumination variation than intensity, which weakens the disturbance of non-uniform illumination in real sequences. Qualitative and quantitative results for synthetic and real-world scenes show that the new method can produce an accurate and robust results.

  13. Robust Inflation from Fibrous Strings

    CERN Document Server

    Burgess, C P; de Alwis, S; Quevedo, F

    2016-01-01

    Successful inflationary models should (i) describe the data well; (ii) arise generically from sensible UV completions; (iii) be insensitive to detailed fine-tunings of parameters and (iv) make interesting new predictions. We argue that a class of models with these properties is characterized by relatively simple potentials with a constant term and negative exponentials. We here continue earlier work exploring UV completions for these models, including the key (though often ignored) issue of modulus stabilisation, to assess the robustness of their predictions. We show that string models where the inflaton is a fibration modulus seem to be robust due to an effective rescaling symmetry, and fairly generic since most known Calabi-Yau manifolds are fibrations. This class of models is characterized by a generic relation between the tensor-to-scalar ratio $r$ and the spectral index $n_s$ of the form $r \\propto (n_s -1)^2$ where the proportionality constant depends on the nature of the effects used to develop the inf...

  14. Robust design of NLF airfoils

    Institute of Scientific and Technical Information of China (English)

    Li Jing; Gao Zhenghong; Huang Jiangtao; Zhao Ke

    2013-01-01

    A robust optimization design approach of natural laminar airfoils is developed in this paper.First,the non-uniform rational B-splines (NURBS) free form deformation method based on NURBS basis function is introduced to the airfoil parameterization.Second,aerodynamic characteristics are evaluated by solving Navier Stokes equations,and the γ-Reθt transition model coupling with shear-stress transport (SST) turbulent model is introduced to simulate boundary layer transition.A numerical simulation of transition flow around NLF0416 airfoil is conducted to test the code.The comparison between numerical simulation results and wind tunnel test data approves the validity and applicability of the present transition model.Third,the optimization system is set up,which uses the separated particle swarm optimization (SPSO) as search algorithm and combines the Kriging models as surrogate model during optimization.The system is applied to carry out robust design about the uncertainty of lift coefficient and Mach number for NASA NLF-0115 airfoil.The data of optimized airfoil aerodynamic characteristics indicates that the optimized airfoil can maintain laminar flow stably in an uncertain range and has a wider range of low drag.

  15. Robust Inflation from fibrous strings

    Energy Technology Data Exchange (ETDEWEB)

    Burgess, C.P. [Department of Physics & Astronomy, McMaster University,1280 Main Street West, Hamilton ON (Canada); Perimeter Institute for Theoretical Physics,31 Caroline Street North, Waterloo ON (Canada); Cicoli, M. [Dipartimento di Fisica e Astronomia, Università di Bologna,via Irnerio 46, 40126 Bologna (Italy); INFN, Sezione di Bologna, Bologna (Italy); Abdus Salam International Center for Theoretical Physics,Strada Costiera 11, Trieste 34014 (Italy); Alwis, S. de [Physics Department, University of Colorado,Boulder, CO 80309 (United States); Quevedo, F. [Abdus Salam International Center for Theoretical Physics,Strada Costiera 11, Trieste 34014 (Italy); DAMTP, University of Cambridge,Wilberforce Road, Cambridge, CB3 0WA (United Kingdom)

    2016-05-13

    Successful inflationary models should (i) describe the data well; (ii) arise generically from sensible UV completions; (iii) be insensitive to detailed fine-tunings of parameters and (iv) make interesting new predictions. We argue that a class of models with these properties is characterized by relatively simple potentials with a constant term and negative exponentials. We here continue earlier work exploring UV completions for these models — including the key (though often ignored) issue of modulus stabilisation — to assess the robustness of their predictions. We show that string models where the inflaton is a fibration modulus seem to be robust due to an effective rescaling symmetry, and fairly generic since most known Calabi-Yau manifolds are fibrations. This class of models is characterized by a generic relation between the tensor-to-scalar ratio r and the spectral index n{sub s} of the form r∝(n{sub s}−1){sup 2} where the proportionality constant depends on the nature of the effects used to develop the inflationary potential and the topology of the internal space. In particular we find that the largest values of the tensor-to-scalar ratio that can be obtained by generalizing the original set-up are of order r≲0.01. We contrast this general picture with specific popular models, such as the Starobinsky scenario and α-attractors. Finally, we argue the self consistency of large-field inflationary models can strongly constrain non-supersymmetric inflationary mechanisms.

  16. On Robust H2 Estimation

    Institute of Scientific and Technical Information of China (English)

    Lihua Xie

    2005-01-01

    The problem of state estimation for uncertain systems has attracted a recurring interest in the past decade. In this paper, we shall give an overview on some of the recent development in the area by focusing on the robust H2 (Kaiman) filtering of uncertain discrete-time systems. The robust H2 estimation is concerned with the design of a fixed estimator for a family of plants under consideration such that the estimation error covariance is of a minimal upper bound. The uncertainty under consideration includes norm-bounded uncertainty and polytopic uncertainty. In the finite horizon case, we shall discuss a parameterized difference Riccati equation approach for systems with normbounded uncertainty and pinpoint the difference of state estimation between systems without uncertainty and those with uncertainty. In the infinite horizon case, we shall deal with both the norm-bounded and polytopic uncertainties using a linear matrix inequality (LMI) approach. In particular, we shall demonstrate how the conservatism of design can be improved using a slack variable technique. We also propose an iterative algorithm to refine a designed estimator. An example will be given to compare estimators designed using various techniques.

  17. Robust distributed cognitive relay beamforming

    KAUST Repository

    Pandarakkottilil, Ubaidulla

    2012-05-01

    In this paper, we present a distributed relay beamformer design for a cognitive radio network in which a cognitive (or secondary) transmit node communicates with a secondary receive node assisted by a set of cognitive non-regenerative relays. The secondary nodes share the spectrum with a licensed primary user (PU) node, and each node is assumed to be equipped with a single transmit/receive antenna. The interference to the PU resulting from the transmission from the cognitive nodes is kept below a specified limit. The proposed robust cognitive relay beamformer design seeks to minimize the total relay transmit power while ensuring that the transceiver signal-to-interference- plus-noise ratio and PU interference constraints are satisfied. The proposed design takes into account a parameter of the error in the channel state information (CSI) to render the performance of the beamformer robust in the presence of imperfect CSI. Though the original problem is non-convex, we show that the proposed design can be reformulated as a tractable convex optimization problem that can be solved efficiently. Numerical results are provided and illustrate the performance of the proposed designs for different network operating conditions and parameters. © 2012 IEEE.

  18. Is Biomedical Waste Management Knowledge Adequate in Paramedics AND Sanitary Workers in Hospitals of Ujjain City?

    Directory of Open Access Journals (Sweden)

    Anand Rajput

    2016-03-01

    Full Text Available "Background: Hospitals produce a byproduct which is wasteful and causes contamination of the environment, with its antecedent complications. Inadequate and inappropriate knowledge of handling may have serious health consequences. Objectives: Present study was conducted to find out the current level of knowledge among paramedics (Lab Technicians, nursing staff and sanitary workers in hospitals of Ujjain city regarding biomedical waste management. Methods: A Cross-sectional study was conducted on 400 study participants in the Government and private hospital of Ujjain city from 1st January 2013 to 30 November 2013.Statistical analysis was done by SPSS 16.0 and chi-square test. Results: Mean age of the total 400 study participants was 31.36 (SD=11.62 years, among them 68.5% were female, majority (64.5% were the nurses and majority (64.7% were working in the concerned hospital since more than 2 years. Nursing staff has adequate knowledge (36.8% as compared to lab technician and sanitary staff (30.3%. Staff who had received medical waste management training had significantly (p<0.05 higher knowledge. Conclusion: On the basis of findings we conclude that the knowledge regarding biomedical waste management is not adequate among nursing staff, lab teqnicians and sanitary workers. " [Natl J Community Med 2016; 7(3.000: 151-154

  19. Maintaining Adequate CO2 Washout for an Advanced EMU via a New Rapid Cycle Amine Technology

    Science.gov (United States)

    Chullen, Cinda; Conger, Bruce

    2012-01-01

    Over the past several years, NASA has realized tremendous progress in Extravehicular Activity (EVA) technology development. This has been evidenced by the progressive development of a new Rapid Cycle Amine (RCA) system for the Advanced Extravehicular Mobility Unit (AEMU) Portable Life Support Subsystem (PLSS). The PLSS is responsible for the life support of the crew member in the spacesuit. The RCA technology is responsible for carbon dioxide (CO2) and humidity control. Another aspect of the RCA is that it is on-back vacuum-regenerable, efficient, and reliable. The RCA also simplifies the PLSS schematic by eliminating the need for a condensing heat exchanger for humidity control in the current EMU. As development progresses on the RCA, it is important that the sizing be optimized so that the demand on the PLSS battery is minimized. As well, maintaining the CO2 washout at adequate levels during an EVA is an absolute requirement of the RCA and associated ventilation system. Testing has been underway in-house at NASA Johnson Space Center and analysis has been initiated to evaluate whether the technology provides exemplary performance in ensuring that the CO2 is removed sufficiently and the ventilation flow is adequate for maintaining CO2 washout in the AEMU spacesuit helmet of the crew member during an EVA. This paper will review the recent developments of the RCA unit, testing planned in-house with a spacesuit simulator, and the associated analytical work along with insights from the medical aspect on the testing. 1

  20. Incentives for an adequate, economic and reliable Swiss transmission grid. Final version

    Energy Technology Data Exchange (ETDEWEB)

    Twomey, P.; Neuhoff, K.; Newbery, D.

    2006-11-15

    This comprehensive final report for the Swiss Federal Office of Energy (SFOE) discusses incentives necessary for the implementation of an adequate, economic and reliable Swiss electricity transmission grid. As Switzerland moves towards a more liberalised and competitive electricity market, an essential task of policy makers will be to ensure that incentives are in place for the construction, maintenance and operation of adequate, economic and reliable transmission infrastructure. As well as continuing to serve the domestic market, the location of Switzerland at the centre of Europe also means that policy should embrace opportunities in servicing the developing European Internal Market by providing transit and other services. Topics discussed include the economic evaluation of transmission investment proposals, regulated transmission investment, investments in transmission lines by power merchants, power auctions and congestion management as well as inter-TSO compensation mechanisms. European regulations and practice are discussed as are access questions and transmission charges. Developments in interconnection management and harmonisation are examined. The particular characteristics of the Swiss energy system, its prices and its legal frameworks are discussed. Cross-border trading and security of supply are also discussed

  1. Are physiotherapy graduates adequately prepared to to manage hiv/aids patients

    Directory of Open Access Journals (Sweden)

    T. Puckree

    2004-02-01

    Full Text Available Physiotherapy learners treat patients with Human Immuno-deficiency Virus/Acquired Immunodeficiency Syndrome (HIV/AIDS. There is no available published research on physiotherapy learners' opinions about how the South Afican physiotherapy undergraduate program is  helping them cope with HIV/AIDS patients. This study determines whether the physiotherapy degree offered at South African Universities, adequately prepares learners to cope with HIV/AIDS patients. Differences in knowledge and attitudes of physiotherapy learners regarding HIV/AIDS, amongst  universities is also explored. Two hundred and two senior physiotherapy learners from eight South African universities returned their  questionnaires and 55% of these were viable for analysis. A large portion (79% of learners indicated that the physiotherapy undergraduate degree did not adequately prepare them to cope with HIV/AIDS patients. Learners' knowledge and attitudes regarding HIV/AIDS differed significantly (41% to 73%  amongst universities. Formal lectures on HIV/AIDS significantly affected knowledge (0% -100% but not attitude towards patients. The role of the physiotherapist, precautions, transmission modes, syndrome stages, counseling and clinical skills were considered critical in the management of HIV/AIDS patients.

  2. Efficient reanalysis techniques for robust topology optimization

    DEFF Research Database (Denmark)

    Amir, Oded; Sigmund, Ole; Lazarov, Boyan Stefanov;

    2012-01-01

    The article focuses on the reduction of the computational effort involved in robust topology optimization procedures. The performance of structures designed by means of topology optimization may be seriously degraded due to fabrication errors. Robust formulations of the optimization problem were...... efficient robust topology optimization procedures based on reanalysis techniques. The approach is demonstrated on two compliant mechanism design problems where robust design is achieved by employing either a worst case formulation or a stochastic formulation. It is shown that the time spent on finite...... element analysis within robust topology optimization can be reduced significantly, without affecting the outcome of the optimization process....

  3. Robust PCA via Outlier Pursuit

    CERN Document Server

    Xu, Huan; Sanghavi, Sujay

    2010-01-01

    Singular Value Decomposition (and Principal Component Analysis) is one of the most widely used techniques for dimensionality reduction: successful and efficiently computable, it is nevertheless plagued by a well-known, well-documented sensitivity to outliers. Recent work has considered the setting where each point has a few arbitrarily corrupted components. Yet, in applications of SVD or PCA such as robust collaborative filtering or bioinformatics, malicious agents, defective genes, or simply corrupted or contaminated experiments may effectively yield entire points that are completely corrupted. We present an efficient convex optimization-based algorithm we call Outlier Pursuit, that under some mild assumptions on the uncorrupted points (satisfied, e.g., by the standard generative assumption in PCA problems) recovers the exact optimal low-dimensional subspace, and identifies the corrupted points. Such identification of corrupted points that do not conform to the low-dimensional approximation, is of paramount ...

  4. Robustness of multimodal processes itineraries

    DEFF Research Database (Denmark)

    Bocewicz, G.; Banaszak, Z.; Nielsen, Izabela Ewa

    2013-01-01

    determining stream-like moving transportation means, a problem of an alternative itinerary selection for an origin–destination (O-D) trip in the context of emergency relief is considered. Emergency relief dealing with the contingency events and deciding on MTS robustness can be evaluated in terms of feasible...... of multimodal processes driven itinerary planning problem is our main contribution. Illustrative examples providing alternative itineraries in some cases of MTS malfunction are presented.......This paper concerns multimodal transport systems (MTS) represented by a supernetworks in which several unimodal networks are connected by transfer links and focuses on the scheduling problems encountered in these systems. Assuming unimodal networks are modeled as cyclic lines, i.e. the routes...

  5. Alternative ways for knowledge collection, indexing and robust language retrieval.

    Science.gov (United States)

    Baud, R H; Lovis, C; Rassinoux, A M; Scherrer, J R

    1998-11-01

    Definitions are provided of the key entities in knowledge representation for Natural Language Processing (NLP). Starting from the words, which are the natural components of any sentence, both the role of expressions and the decomposition of words into their parts are emphasized. This leads to the notion of concepts, which are either primitive or composite depending on the model where they are created. The problem of finding the most adequate degree of granularity for a concept is studied. From this reflection on basic Natural Language Processing components, four categories of linguistic knowledge are recognized, that are considered to be the building blocks of a Medical Linguistic Knowledge Base (MLKB). Following on the tracks of a recent experience in building a natural language-based patient encoding browser, a robust method for conceptual indexing and query of medical texts is presented with particular attention to the scheme of knowledge representation.

  6. 21 CFR 740.10 - Labeling of cosmetic products for which adequate substantiation of safety has not been obtained.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Labeling of cosmetic products for which adequate..., DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS Warning Statements § 740.10 Labeling of cosmetic products for which adequate substantiation of safety has not...

  7. An Adequate Approach to Image Retrieval Based on Local Level Feature Extraction

    Directory of Open Access Journals (Sweden)

    Sumaira Muhammad Hayat Khan

    2010-10-01

    Full Text Available Image retrieval based on text annotation has become obsolete and is no longer interesting for scientists because of its high time complexity and low precision in results. Alternatively, increase in the amount of digital images has generated an excessive need for an accurate and efficient retrieval system. This paper proposes content based image retrieval technique at a local level incorporating all the rudimentary features. Image undergoes the segmentation process initially and each segment is then directed to the feature extraction process. The proposed technique is also based on image?s content which primarily includes texture, shape and color. Besides these three basic features, FD (Fourier Descriptors and edge histogram descriptors are also calculated to enhance the feature extraction process by taking hold of information at the boundary. Performance of the proposed method is found to be quite adequate when compared with the results from one of the best local level CBIR (Content Based Image Retrieval techniques.

  8. Adequate bases of phase space master integrals for $gg \\to h$ at NNLO and beyond

    CERN Document Server

    Höschele, Maik; Ueda, Takahiro

    2014-01-01

    We study master integrals needed to compute the Higgs boson production cross section via gluon fusion in the infinite top quark mass limit, using a canonical form of differential equations for master integrals, recently identified by Henn, which makes their solution possible in a straightforward algebraic way. We apply the known criteria to derive such a suitable basis for all the phase space master integrals in afore mentioned process at next-to-next-to-leading order in QCD and demonstrate that the method is applicable to next-to-next-to-next-to-leading order as well by solving a non-planar topology. Furthermore, we discuss in great detail how to find an adequate basis using practical examples. Special emphasis is devoted to master integrals which are coupled by their differential equations.

  9. Adequate bases of phase space master integrals for gg → h at NNLO and beyond

    Science.gov (United States)

    Höschele, Maik; Hoff, Jens; Ueda, Takahiro

    2014-09-01

    We study master integrals needed to compute the Higgs boson production cross section via gluon fusion in the infinite top quark mass limit, using a canonical form of differential equations for master integrals, recently identified by Henn, which makes their solution possible in a straightforward algebraic way. We apply the known criteria to derive such a suitable basis for all the phase space master integrals in afore mentioned process at next-to-next-to-leading order in QCD and demonstrate that the method is applicable to next-to-next-to-next-to-leading order as well by solving a non-planar topology. Furthermore, we discuss in great detail how to find an adequate basis using practical examples. Special emphasis is devoted to master integrals which are coupled by their differential equations.

  10. Matching occupation and self: does matching theory adequately model children's thinking?

    Science.gov (United States)

    Watson, Mark; McMahon, Mary

    2004-10-01

    The present exploratory-descriptive cross-national study focused on the career development of 11- to 14-yr.-old children, in particular whether they can match their personal characteristics with their occupational aspirations. Further, the study explored whether their matching may be explained in terms of a fit between person and environment using Holland's theory as an example. Participants included 511 South African and 372 Australian children. Findings relate to two items of the Revised Career Awareness Survey that require children to relate personal-social knowledge to their favorite occupation. Data were analyzed in three stages using descriptive statistics, i.e., mean scores, frequencies, and percentage agreement. The study indicated that children perceived their personal characteristics to be related to their occupational aspirations. However, how this matching takes place is not adequately accounted for in terms of a career theory such as that of Holland.

  11. Use of Linear Programming to Develop Cost-Minimized Nutritionally Adequate Health Promoting Food Baskets

    Science.gov (United States)

    Tetens, Inge; Dejgård Jensen, Jørgen; Smed, Sinne; Gabrijelčič Blenkuš, Mojca; Rayner, Mike; Darmon, Nicole; Robertson, Aileen

    2016-01-01

    Background Food-Based Dietary Guidelines (FBDGs) are developed to promote healthier eating patterns, but increasing food prices may make healthy eating less affordable. The aim of this study was to design a range of cost-minimized nutritionally adequate health-promoting food baskets (FBs) that help prevent both micronutrient inadequacy and diet-related non-communicable diseases at lowest cost. Methods Average prices for 312 foods were collected within the Greater Copenhagen area. The cost and nutrient content of five different cost-minimized FBs for a family of four were calculated per day using linear programming. The FBs were defined using five different constraints: cultural acceptability (CA), or dietary guidelines (DG), or nutrient recommendations (N), or cultural acceptability and nutrient recommendations (CAN), or dietary guidelines and nutrient recommendations (DGN). The variety and number of foods in each of the resulting five baskets was increased through limiting the relative share of individual foods. Results The one-day version of N contained only 12 foods at the minimum cost of DKK 27 (€ 3.6). The CA, DG, and DGN were about twice of this and the CAN cost ~DKK 81 (€ 10.8). The baskets with the greater variety of foods contained from 70 (CAN) to 134 (DGN) foods and cost between DKK 60 (€ 8.1, N) and DKK 125 (€ 16.8, DGN). Ensuring that the food baskets cover both dietary guidelines and nutrient recommendations doubled the cost while cultural acceptability (CAN) tripled it. Conclusion Use of linear programming facilitates the generation of low-cost food baskets that are nutritionally adequate, health promoting, and culturally acceptable. PMID:27760131

  12. Building Robust Systems with Fallible Construction (Elaboration de systemes informatiques robustes a l’architecutre faillible)

    Science.gov (United States)

    2008-04-01

    IST-047 Building Robust Systems with Fallible Construction (Elaboration de systèmes informatiques robustes à l’architecture faillible) Final...IST-047 Building Robust Systems with Fallible Construction (Elaboration de systèmes informatiques robustes à l’architecture faillible...and cost investments. ES - 2 RTO-TR-IST-047 Elaboration de systèmes informatiques robustes à l’architecture faillible (RTO-TR-IST-047

  13. Early eruption of permanent canines

    Directory of Open Access Journals (Sweden)

    S Madhu

    2012-01-01

    Full Text Available Systemic and local factors can modify the eruption time of teeth. Generalized eruption time changes could be due to some systemic diseases like hyperthyroidism, hypophosphatasia, precocious puberty, Proteus syndrome, etc. Localized early eruption of permanent teeth could be due to early extraction of deciduous teeth. Presented here is an extremely rare case of early eruption of permanent canines in a 7-year old female child. Though the number of such cases is very limited, the clinician should poses adequate knowledge and keeps an open eye to identify such cases.

  14. Negative autoregulation by FAS mediates robust fetal erythropoiesis.

    Directory of Open Access Journals (Sweden)

    Merav Socolovsky

    2007-10-01

    Full Text Available Tissue development is regulated by signaling networks that control developmental rate and determine ultimate tissue mass. Here we present a novel computational algorithm used to identify regulatory feedback and feedforward interactions between progenitors in developing erythroid tissue. The algorithm makes use of dynamic measurements of red cell progenitors between embryonic days 12 and 15 in the mouse. It selects for intercellular interactions that reproduce the erythroid developmental process and endow it with robustness to external perturbations. This analysis predicts that negative autoregulatory interactions arise between early erythroblasts of similar maturation stage. By studying embryos mutant for the death receptor FAS, or for its ligand, FASL, and by measuring the rate of FAS-mediated apoptosis in vivo, we show that FAS and FASL are pivotal negative regulators of fetal erythropoiesis, in the manner predicted by the computational model. We suggest that apoptosis in erythroid development mediates robust homeostasis regulating the number of red blood cells reaching maturity.

  15. Robustness or resilience? Managing the intersection of ecology and engineering in an urban Alaskan fishery

    Directory of Open Access Journals (Sweden)

    Meagan B. Krupa

    2014-06-01

    Full Text Available Systems theories of robustness and resilience, which are derived from engineering and ecology, respectively, have been increasingly applied to social-ecological systems (SESs. Social-ecological robustness has been applied primarily to management of physical dimensions of SESs (e.g., water management and resilience to management of ecological dimensions of SESs (e.g., rangelands. However, cases of highly engineered systems have yet to be adequately evaluated by either approach. We find the robustness framework serves to better explain management options of a highly engineered, ecologically-based SES, the lower Ship Creek fishery in Anchorage, Alaska, USA. Robustness applies well to this system because its dynamics are highly engineered through both structures and institutions. Even the salmon are products of a hatchery fishery that operates independently of many ecological variables and feedbacks within the system. However, robustness theory has yet to develop a prescriptive method for management that can assist practitioners. We conclude by applying Ostrom's design principles to the system dynamics to assess opportunities for increasing the robustness of this urban fishery.

  16. Quantifying the robustness of metro networks

    CERN Document Server

    Wang, Xiangrong; Derrible, Sybil; Ahmad, Sk Nasir; Kooij, Robert E

    2015-01-01

    Metros (heavy rail transit systems) are integral parts of urban transportation systems. Failures in their operations can have serious impacts on urban mobility, and measuring their robustness is therefore critical. Moreover, as physical networks, metros can be viewed as network topological entities, and as such they possess measurable network properties. In this paper, by using network science and graph theoretical concepts, we investigate both theoretical and experimental robustness metrics (i.e., the robustness indicator, the effective graph conductance, and the critical thresholds) and their performance in quantifying the robustness of metro networks under random failures or targeted attacks. We find that the theoretical metrics quantify different aspects of the robustness of metro networks. In particular, the robustness indicator captures the number of alternative paths and the effective graph conductance focuses on the length of each path. Moreover, the high positive correlation between the theoretical m...

  17. Synchronization of a class of chaotic signals via robust observer design

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar-Lopez, Ricardo [Departamento de Energia, Universidad Autonoma Metropolitana - Azcapotzalco, San Pablo 180, Reynosa-Tamaulipas, Azcapotzalco 02200, Mexico, D.F. (Mexico)], E-mail: raguilar@correo.azc.uam.mx; Martinez-Guerra, Rafael [Departamento de Energia, Universidad Autonoma Metropolitana - Azcapotzalco, San Pablo 180, Reynosa-Tamaulipas, Azcapotzalco 02200, Mexico, D.F. (Mexico); Departamento de Control Automatico, CINVESTAV IPN, Apartado Postal 14-740, Mexico, D.F. C.P. 07360 (Mexico)], E-mail: rguerra@ctrl.cinvestav.mx

    2008-07-15

    In this paper the signal synchronization of a class of chaotic systems based on robust observer design is tackled. The task is the synchronization of the signals generated by two Chen oscillators with different initial condition. The proposed observer is robust against model uncertainties and noisy output measurements. An alternative system representation is proposed to transform the measured disturbance onto system disturbance, which leads a more adequate observer structure. The proposed methodology contains an uncertainty estimator based on the predictive contribution to infer the unobservable uncertainties and corrective contribution to estimate the observable uncertainties; which provides robustness against noisy measurements and model uncertainties. Convergence analysis of the proposed estimation methodology is realized, analyzing the dynamic equation of the estimation error, where asymptotic convergence is shown. Numerical experiments illustrate the good performance of the proposed methodology.

  18. Robustness of timber structures in seismic areas

    OpenAIRE

    Neves, Luís A.C.; Branco, Jorge M.

    2011-01-01

    Major similarities between robustness assessment and seismic design exist, and significant information can be brought from seismic design to robustness design. As will be discussed, although some methods and limitations considered in seismic design can improve robustness, the capacity of the structure to sustain limited damage without disproportionate effects is significantly more complex. In fact, seismic design can either improve or reduce the resistance of structures to unfo...

  19. Robust chaos in smooth unimodal maps

    Science.gov (United States)

    Andrecut, M.; Ali, M. K.

    2001-08-01

    Robust chaos is defined by the absence of periodic windows and coexisting attractors in some neighborhood of the parameter space. It has been conjectured that robust chaos cannot occur in smooth systems [E. Barreto, B. Hunt, and C. Grebogi, Phys. Rev. Lett. 78, 4561 (1997); 80, 3049 (1998)]. Contrary to this conjecture, we describe a general procedure for generating robust chaos in smooth unimodal maps.

  20. Nonlinear Robust Control for Spacecraft Attitude

    Directory of Open Access Journals (Sweden)

    Wang Lina

    2013-07-01

    Full Text Available Nonlinear robust control of the spacecraft attitude with the existence of external disturbances is considered. A robust attitude controller is designed based on the passivity approach the quaternion representation, which introduces the suppression vector of external disturbance into the control law and does not need angular velocity measurement. Stability conditions of the robust attitude controller are given. And the numerical simulation results show the effectiveness of the attitude controller.

  1. Robust algebraic image enhancement for intelligent control systems

    Science.gov (United States)

    Lerner, Bao-Ting; Morrelli, Michael

    1993-01-01

    Robust vision capability for intelligent control systems has been an elusive goal in image processing. The computationally intensive techniques a necessary for conventional image processing make real-time applications, such as object tracking and collision avoidance difficult. In order to endow an intelligent control system with the needed vision robustness, an adequate image enhancement subsystem capable of compensating for the wide variety of real-world degradations, must exist between the image capturing and the object recognition subsystems. This enhancement stage must be adaptive and must operate with consistency in the presence of both statistical and shape-based noise. To deal with this problem, we have developed an innovative algebraic approach which provides a sound mathematical framework for image representation and manipulation. Our image model provides a natural platform from which to pursue dynamic scene analysis, and its incorporation into a vision system would serve as the front-end to an intelligent control system. We have developed a unique polynomial representation of gray level imagery and applied this representation to develop polynomial operators on complex gray level scenes. This approach is highly advantageous since polynomials can be manipulated very easily, and are readily understood, thus providing a very convenient environment for image processing. Our model presents a highly structured and compact algebraic representation of grey-level images which can be viewed as fuzzy sets.

  2. Adequate sleep among adolescents is positively associated with health status and health-related behaviors

    Directory of Open Access Journals (Sweden)

    Jeng Yi-Jong

    2006-03-01

    Full Text Available Abstract Background Amount of sleep is an important indicator of health and well-being in children and adolescents. Adequate sleep (AS: adequate sleep is defined as 6–8 hours per night regularly is a critical factor in adolescent health and health-related behaviors. The present study was based on a health promotion project previously conducted on adolescents in Tao-Yuan County, Taiwan. The aim was to examine the relationship between AS during schooldays and excessive body weight, frequency of visiting doctors and health-related behaviors among Taiwanese adolescents. Methods A cross-sectional study design, categorical and multivariate data analyses were used. The hypotheses investigated were: high frequency of AS is positively associated with lack of obesity and less frequent visits to doctors; and high frequency AS is positively associated with health-related behavior. Results A total of 656 boys (53.2% and girls (46.8%, ranging in age from 13–18 years were studied between January and June 2004. Three hundred and fifty seven subjects (54% reported that they slept less than the suggested 6–8 hours on schooldays. A significant negative association was found between low sleep and of the following health-related behaviors: (1 life appreciation; (2 taking responsibility for health; (3 adopting healthy diet; (4 effective stress management; (5 regular exercise; and (6 total AHP score. High frequency AS was associated with low frequencies of obesity after potential confounding factors were controlled. Junior high school adolescents reported significantly higher frequencies of AS than high school participants. Gender, family structure, home location and frequency of television watching or computer use were not significantly associated with AS. Conclusion These findings support the proposition that AS is associated with good health status and high-frequency adoption of health-related behavior. Furthermore, these findings suggest that inadequate

  3. Designing for Reliability and Robustness

    Science.gov (United States)

    Svetlik, Randall G.; Moore, Cherice; Williams, Antony

    2017-01-01

    Long duration spaceflight has a negative effect on the human body, and exercise countermeasures are used on-board the International Space Station (ISS) to minimize bone and muscle loss, combatting these effects. Given the importance of these hardware systems to the health of the crew, this equipment must continue to be readily available. Designing spaceflight exercise hardware to meet high reliability and availability standards has proven to be challenging throughout the time the crewmembers have been living on ISS beginning in 2000. Furthermore, restoring operational capability after a failure is clearly time-critical, but can be problematic given the challenges of troubleshooting the problem from 220 miles away. Several best-practices have been leveraged in seeking to maximize availability of these exercise systems, including designing for robustness, implementing diagnostic instrumentation, relying on user feedback, and providing ample maintenance and sparing. These factors have enhanced the reliability of hardware systems, and therefore have contributed to keeping the crewmembers healthy upon return to Earth. This paper will review the failure history for three spaceflight exercise countermeasure systems identifying lessons learned that can help improve future systems. Specifically, the Treadmill with Vibration Isolation and Stabilization System (TVIS), Cycle Ergometer with Vibration Isolation and Stabilization System (CEVIS), and the Advanced Resistive Exercise Device (ARED) will be reviewed, analyzed, and conclusions identified so as to provide guidance for improving future exercise hardware designs. These lessons learned, paired with thorough testing, offer a path towards reduced system down-time.

  4. Nanotechnology Based Environmentally Robust Primers

    Energy Technology Data Exchange (ETDEWEB)

    Barbee, T W Jr; Gash, A E; Satcher, J H Jr; Simpson, R L

    2003-03-18

    An initiator device structure consisting of an energetic metallic nano-laminate foil coated with a sol-gel derived energetic nano-composite has been demonstrated. The device structure consists of a precision sputter deposition synthesized nano-laminate energetic foil of non-toxic and non-hazardous metals along with a ceramic-based energetic sol-gel produced coating made up of non-toxic and non-hazardous components such as ferric oxide and aluminum metal. Both the nano-laminate and sol-gel technologies are versatile commercially viable processes that allow the ''engineering'' of properties such as mechanical sensitivity and energy output. The nano-laminate serves as the mechanically sensitive precision igniter and the energetic sol-gel functions as a low-cost, non-toxic, non-hazardous booster in the ignition train. In contrast to other energetic nanotechnologies these materials can now be safely manufactured at application required levels, are structurally robust, have reproducible and engineerable properties, and have excellent aging characteristics.

  5. Efficient robust conditional random fields.

    Science.gov (United States)

    Song, Dongjin; Liu, Wei; Zhou, Tianyi; Tao, Dacheng; Meyer, David A

    2015-10-01

    Conditional random fields (CRFs) are a flexible yet powerful probabilistic approach and have shown advantages for popular applications in various areas, including text analysis, bioinformatics, and computer vision. Traditional CRF models, however, are incapable of selecting relevant features as well as suppressing noise from noisy original features. Moreover, conventional optimization methods often converge slowly in solving the training procedure of CRFs, and will degrade significantly for tasks with a large number of samples and features. In this paper, we propose robust CRFs (RCRFs) to simultaneously select relevant features. An optimal gradient method (OGM) is further designed to train RCRFs efficiently. Specifically, the proposed RCRFs employ the l1 norm of the model parameters to regularize the objective used by traditional CRFs, therefore enabling discovery of the relevant unary features and pairwise features of CRFs. In each iteration of OGM, the gradient direction is determined jointly by the current gradient together with the historical gradients, and the Lipschitz constant is leveraged to specify the proper step size. We show that an OGM can tackle the RCRF model training very efficiently, achieving the optimal convergence rate [Formula: see text] (where k is the number of iterations). This convergence rate is theoretically superior to the convergence rate O(1/k) of previous first-order optimization methods. Extensive experiments performed on three practical image segmentation tasks demonstrate the efficacy of OGM in training our proposed RCRFs.

  6. [Survey of Trichophyton tonsurans infection in Japan. Molecular epidemiology and factors affecting adequate hairbrush sampling].

    Science.gov (United States)

    Mochizuki, Takashi; Tanabe, Hiroshi; Wakasa, Asako; Kawasaki, Masako; Anzawa, Kazushi; Ishizaki, Hiroshi

    2006-01-01

    At the 48th Annual Meeting of The Society for Japanese Medical Mycology, held in October, 2004, we reported our findings from a survey on Trichophyton tonsurans infections in the Hokuriku and Kinki regions of Japan. The survey revealed that a few epidemics had occurred across these regions. In this article, we introduce our subsequent studies relating to 1) molecular epidemiology of isolates taken from people in many parts of Japan and 2) factors affecting adequate sampling of the scalp with hairbrushes, essential for surveying and monitoring the infection. In total, 198 isolates of Trichophyton tonsurans were analyzed using restriction fragment length polymorphisms of the non-transcribed spacer regions of ribosomal RNA genes. The restriction enzyme Mva I indicated two molecular types of strains, implying that the causative agents of the epidemic had different origins. None of the isolates obtained from the epidemic showed the same restriction profile as that of isolates from aged and sporadic cases. The published hairbrush method suitable for obtaining samples from the scalp of Judo trainees was reevaluated by changing several factors. We found that sampling should not be done soon after the students' physical training because other fungal elements may give a false positive, samples should not be obtained from students who have recently applied topical antimycotics, and samples should be taken under the guidance of qualified instructors familiar with the sampling method.

  7. An adequate interset rest period for strength recovery during a common isokinetic test.

    Science.gov (United States)

    Blazquez, Ivan N; Warren, Barbara L; O'Hanlon, Ann M; Silvestri, Lynette R

    2013-07-01

    Isokinetic testing is used in rehabilitation settings on a regular basis; yet, there is a lack of consistency in rest period usage among protocols. Furthermore, the allotment of rest periods has been arbitrary (e.g., 30, 60, 90 seconds or more). This investigation examines the work:rest ratio as an effective method of standardizing rest periods in isokinetic testing. The purpose of this study was to establish an adequate rest period that would allow reproducibility of strength during a common isokinetic strength test. Twenty-seven healthy college-aged men (age, 23 ± 3.8 years; body weight, 79.54 ± 11.09 kg) were tested on 5 separate occasions: 2 familiarization sessions and 3 experimental sessions. Each subject performed a knee extension/flexion isokinetic strength protocol (Cybex NORM; Lumex, Inc., Ronkonkoma, NY, USA) to determine peak torque by performing 5 maximal reciprocal repetitions at each ascending velocity of 60, 180, and 300°·s. Work:rest ratios of 1:3, 1:8, and 1:12 were counterbalanced between sets. A 3 × 3 repeated measures analysis of variance was used to analyze the data. A significance level of α ≤ 0.05 was used for all tests. There was no significant difference in either knee extension or knee flexion peak torque when comparing work:rest ratios. These findings suggest that a 1:3 work:rest ratio is sufficient during a common isokinetic strength test.

  8. Are Nutritional Care Adequate for Elderly Hospitalized Patients? A Cross-Sectional Study

    Directory of Open Access Journals (Sweden)

    Helene Kjøllesdal Eide

    2016-12-01

    Full Text Available This article assesses nutritional care in identifying and treating nutritional risk in elderly hospitalized patients. A cross-sectional study was conducted at a large Norwegian University hospital in the period 2011 to 2013. Data on nutritional risk and care for elderly patients (≥70 years without dementia were collected at 20 wards by 173 second-year nursing students in acute-care clinical studies. A stratified sampling technique was utilized to improve the representativeness of the sample. In total, 508 patients (48.8% women with a mean age of 79.6 years participated. The internationally and nationally recommended nutritional care was not implemented at the hospital, suggesting that nutritional care for elderly hospitalized patients was not adequate. This implies that the majority of the elderly patients nutritionally at risk are neither identified nor treated according to their needs. The article highlights the importance of having systematic nutritional care practices to make it possible for the hospital ward staff to routinely identify nutritional risk and initiate appropriate nutritional treatment measures.

  9. A high UV environment does not ensure adequate Vitamin D status

    Science.gov (United States)

    Kimlin, M. G.; Lang, C. A.; Brodie, A.; Harrison, S.; Nowak, M.; Moore, M. R.

    2006-12-01

    Queensland has the highest rates of skin cancer in the world and due to the high levels of solar UV in this region it is assumed that incidental UV exposure should provide adequate vitamin D status for the population. This research was undertaken to test this assumption among healthy free-living adults in south-east Queensland, Australia (27°S), at the end of winter. This research was approved by Queensland University of Technology Human Research Ethics Committee and conducted under the guidelines of the Declaration of Helsinki. 10.2% of the sample had serum vitamin D levels below 25nm/L (deficiency) and a further 32.3% had levels between 25nm/L and 50nm/L (insufficiency). Vitamin D deficiency and insufficiency can occur at the end of winter, even in sunny climates. The wintertime UV levels in south-east Queensland (UV index 4-6) are equivalent to summertime UV levels in northern regions of Europe and the USA. These ambient UV levels are sufficient to ensure synthesis of vitamin D requirements. We investigated individual UV exposure (through a self reported sun exposure questionnaire) and found correlations between exposure and Vitamin D status. Further research is needed to explore the interactions between the solar UV environment and vitamin D status, particularly in high UV environments, such as Queensland.

  10. Twenty-Four-Hour Urine Osmolality as a Physiological Index of Adequate Water Intake

    Directory of Open Access Journals (Sweden)

    Erica T. Perrier

    2015-01-01

    Full Text Available While associations exist between water, hydration, and disease risk, research quantifying the dose-response effect of water on health is limited. Thus, the water intake necessary to maintain optimal hydration from a physiological and health standpoint remains unclear. The aim of this analysis was to derive a 24 h urine osmolality (UOsm threshold that would provide an index of “optimal hydration,” sufficient to compensate water losses and also be biologically significant relative to the risk of disease. Ninety-five adults (31.5 ± 4.3 years, 23.2 ± 2.7 kg·m−2 collected 24 h urine, provided morning blood samples, and completed food and fluid intake diaries over 3 consecutive weekdays. A UOsm threshold was derived using 3 approaches, taking into account European dietary reference values for water; total fluid intake, and urine volumes associated with reduced risk for lithiasis and chronic kidney disease and plasma vasopressin concentration. The aggregate of these approaches suggest that a 24 h urine osmolality ≤500 mOsm·kg−1 may be a simple indicator of optimal hydration, representing a total daily fluid intake adequate to compensate for daily losses, ensure urinary output sufficient to reduce the risk of urolithiasis and renal function decline, and avoid elevated plasma vasopressin concentrations mediating the increased antidiuretic effort.

  11. Improved ASTM G72 Test Method for Ensuring Adequate Fuel-to-Oxidizer Ratios

    Science.gov (United States)

    Juarez, Alfredo; Harper, Susana Tapia

    2016-01-01

    The ASTM G72/G72M-15 Standard Test Method for Autogenous Ignition Temperature of Liquids and Solids in a High-Pressure Oxygen-Enriched Environment is currently used to evaluate materials for the ignition susceptibility driven by exposure to external heat in an enriched oxygen environment. Testing performed on highly volatile liquids such as cleaning solvents has proven problematic due to inconsistent test results (non-ignitions). Non-ignition results can be misinterpreted as favorable oxygen compatibility, although they are more likely associated with inadequate fuel-to-oxidizer ratios. Forced evaporation during purging and inadequate sample size were identified as two potential causes for inadequate available sample material during testing. In an effort to maintain adequate fuel-to-oxidizer ratios within the reaction vessel during test, several parameters were considered, including sample size, pretest sample chilling, pretest purging, and test pressure. Tests on a variety of solvents exhibiting a range of volatilities are presented in this paper. A proposed improvement to the standard test protocol as a result of this evaluation is also presented. Execution of the final proposed improved test protocol outlines an incremental step method of determining optimal conditions using increased sample sizes while considering test system safety limits. The proposed improved test method increases confidence in results obtained by utilizing the ASTM G72 autogenous ignition temperature test method and can aid in the oxygen compatibility assessment of highly volatile liquids and other conditions that may lead to false non-ignition results.

  12. Are GPs adequately equipped with the knowledge for educating and counseling of families with ADHD children?

    Directory of Open Access Journals (Sweden)

    Zarei Nabi

    2010-01-01

    Full Text Available Abstract Background Attention deficit hyperactivity disorder is one of the most common child psychiatry disorders. General physicians (GP, as primary care providers, can have an important role in screening and treatment of ADHD. This study aimed to survey GPs' knowledge, attitude, and their views of their role in the screening, diagnosing and managing children with ADHD. Methods Six hundred and sixty five general physicians in Shiraz, Iran, answered a self-reported questionnaire on ADHD. The questionnaire consisted of questions regarding socio-demographic characteristics such as age, the duration of practice as a GP, marital status, general knowledge about ADHD, and the management of ADHD. Results Less than half of them believed that they have adequate knowledge and information about this disorder. They usually do not like to be the primary care providers for children with ADHD. The majority of them prefer to refer the children to related specialists, mostly psychiatrists or psychologists. More than one third of them believed that sugar is a cause of ADHD. Only 6.6% of them reported that ADHD persists for the whole life. Their knowledge about methylphenidate is reasonable. Conclusions As many other countries worldwide, the knowledge of GPs about ADHD should be improved. They do not asses and manage children with probable ADHD by themselves without referring to related professionals. They do not opt for the use of methylphenidate.

  13. Aurally-adequate time-frequency analysis for scattered sound in auditoria

    Science.gov (United States)

    Norris, Molly K.; Xiang, Ning; Kleiner, Mendel

    2005-04-01

    The goal of this work was to apply an aurally-adequate time-frequency analysis technique to the analysis of sound scattering effects in auditoria. Time-frequency representations were developed as a motivated effort that takes into account binaural hearing, with a specific implementation of interaural cross-correlation process. A model of the human auditory system was implemented in the MATLAB platform based on two previous models [A. Härmä and K. Palomäki, HUTear, Espoo, Finland; and M. A. Akeroyd, A. Binaural Cross-correlogram Toolbox for MATLAB (2001), University of Sussex, Brighton]. These stages include proper frequency selectivity, the conversion of the mechanical motion of the basilar membrane to neural impulses, and binaural hearing effects. The model was then used in the analysis of room impulse responses with varying scattering characteristics. This paper discusses the analysis results using simulated and measured room impulse responses. [Work supported by the Frank H. and Eva B. Buck Foundation.

  14. Assessing pharmacokinetics of different doses of fosfomycin in laboratory rats enables adequate exposure for pharmacodynamic models.

    Science.gov (United States)

    Poeppl, Wolfgang; Lingscheid, Tilman; Bernitzky, Dominik; Donath, Oliver; Reznicek, Gottfried; Zeitlinger, Markus; Burgmann, Heinz

    2014-01-01

    Fosfomycin has been the subject of numerous pharmacodynamic in vivo models in recent years. The present study set out to determine fosfomycin pharmacokinetics in laboratory rats to enable adequate dosing regimens in future rodent models. Fosfomycin was given intraperitoneally as single doses of 75, 200 and 500 mg/kg bodyweight to 4 Sprague-Dawley rats per dose group. Blood samples were collected over 8 h and fosfomycin concentrations were determined by HPLC-mass spectrometry. Fosfomycin showed a dose-proportional pharmacokinetic profile indicated by a correlation of 0.99 for maximum concentration and area under the concentration-time curve (AUC). The mean AUC0-8 after intraperitoneal administration of 75, 200 or 500 mg/kg bodyweight fosfomycin were 109.4, 387.0 and 829.1 µg·h/ml, respectively. In conclusion, a dosing regimen of 200-500 mg/kg 3 times daily is appropriate to obtain serum concentrations in laboratory rats, closely mimicking human serum concentrations over time.

  15. Quality Support Infrastructure in Early Childhood: Still (Mostly) Missing

    Science.gov (United States)

    Azzi-Lessing, Lenette

    2009-01-01

    Support for early care and education among policy makers and the public is at an unprecedented high. As investments in early care and education programs in the United States continue to rise, the issue of quality becomes increasingly critical. This article addresses the need for adequate infrastructure to support high-quality early care and…

  16. Noise and robustness in phyllotaxis.

    Science.gov (United States)

    Mirabet, Vincent; Besnard, Fabrice; Vernoux, Teva; Boudaoud, Arezki

    2012-01-01

    A striking feature of vascular plants is the regular arrangement of lateral organs on the stem, known as phyllotaxis. The most common phyllotactic patterns can be described using spirals, numbers from the Fibonacci sequence and the golden angle. This rich mathematical structure, along with the experimental reproduction of phyllotactic spirals in physical systems, has led to a view of phyllotaxis focusing on regularity. However all organisms are affected by natural stochastic variability, raising questions about the effect of this variability on phyllotaxis and the achievement of such regular patterns. Here we address these questions theoretically using a dynamical system of interacting sources of inhibitory field. Previous work has shown that phyllotaxis can emerge deterministically from the self-organization of such sources and that inhibition is primarily mediated by the depletion of the plant hormone auxin through polarized transport. We incorporated stochasticity in the model and found three main classes of defects in spiral phyllotaxis--the reversal of the handedness of spirals, the concomitant initiation of organs and the occurrence of distichous angles--and we investigated whether a secondary inhibitory field filters out defects. Our results are consistent with available experimental data and yield a prediction of the main source of stochasticity during organogenesis. Our model can be related to cellular parameters and thus provides a framework for the analysis of phyllotactic mutants at both cellular and tissular levels. We propose that secondary fields associated with organogenesis, such as other biochemical signals or mechanical forces, are important for the robustness of phyllotaxis. More generally, our work sheds light on how a target pattern can be achieved within a noisy background.

  17. Noise and robustness in phyllotaxis.

    Directory of Open Access Journals (Sweden)

    Vincent Mirabet

    Full Text Available A striking feature of vascular plants is the regular arrangement of lateral organs on the stem, known as phyllotaxis. The most common phyllotactic patterns can be described using spirals, numbers from the Fibonacci sequence and the golden angle. This rich mathematical structure, along with the experimental reproduction of phyllotactic spirals in physical systems, has led to a view of phyllotaxis focusing on regularity. However all organisms are affected by natural stochastic variability, raising questions about the effect of this variability on phyllotaxis and the achievement of such regular patterns. Here we address these questions theoretically using a dynamical system of interacting sources of inhibitory field. Previous work has shown that phyllotaxis can emerge deterministically from the self-organization of such sources and that inhibition is primarily mediated by the depletion of the plant hormone auxin through polarized transport. We incorporated stochasticity in the model and found three main classes of defects in spiral phyllotaxis--the reversal of the handedness of spirals, the concomitant initiation of organs and the occurrence of distichous angles--and we investigated whether a secondary inhibitory field filters out defects. Our results are consistent with available experimental data and yield a prediction of the main source of stochasticity during organogenesis. Our model can be related to cellular parameters and thus provides a framework for the analysis of phyllotactic mutants at both cellular and tissular levels. We propose that secondary fields associated with organogenesis, such as other biochemical signals or mechanical forces, are important for the robustness of phyllotaxis. More generally, our work sheds light on how a target pattern can be achieved within a noisy background.

  18. Noise and Robustness in Phyllotaxis

    Science.gov (United States)

    Mirabet, Vincent; Besnard, Fabrice; Vernoux, Teva; Boudaoud, Arezki

    2012-01-01

    A striking feature of vascular plants is the regular arrangement of lateral organs on the stem, known as phyllotaxis. The most common phyllotactic patterns can be described using spirals, numbers from the Fibonacci sequence and the golden angle. This rich mathematical structure, along with the experimental reproduction of phyllotactic spirals in physical systems, has led to a view of phyllotaxis focusing on regularity. However all organisms are affected by natural stochastic variability, raising questions about the effect of this variability on phyllotaxis and the achievement of such regular patterns. Here we address these questions theoretically using a dynamical system of interacting sources of inhibitory field. Previous work has shown that phyllotaxis can emerge deterministically from the self-organization of such sources and that inhibition is primarily mediated by the depletion of the plant hormone auxin through polarized transport. We incorporated stochasticity in the model and found three main classes of defects in spiral phyllotaxis – the reversal of the handedness of spirals, the concomitant initiation of organs and the occurrence of distichous angles – and we investigated whether a secondary inhibitory field filters out defects. Our results are consistent with available experimental data and yield a prediction of the main source of stochasticity during organogenesis. Our model can be related to cellular parameters and thus provides a framework for the analysis of phyllotactic mutants at both cellular and tissular levels. We propose that secondary fields associated with organogenesis, such as other biochemical signals or mechanical forces, are important for the robustness of phyllotaxis. More generally, our work sheds light on how a target pattern can be achieved within a noisy background. PMID:22359496

  19. Determinants of prompt and adequate care among presumed malaria cases in a community in eastern Rwanda: A cross sectional study

    NARCIS (Netherlands)

    Ingabire, C.M.; Kateera, F.; Hakizimana, E.; Rulisa, A.; Muvunyi, C.; Mens, P.; Koenraadt, C.J.M.; Mutesa, L.; Vugt, M. van; Borne, B. van den; Alaii, J.

    2016-01-01

    Background: In order to understand factors influencing fever/malaria management practices among community-based individuals, the study evaluated psychosocial, socio-demographic and environmental determinants of prompt and adequate healthcare-seeking behaviours. Methods: A quantitative household (HH)

  20. Robustness of Long Span Reciprocal Timber Structures

    DEFF Research Database (Denmark)

    Balfroid, Nathalie; Kirkegaard, Poul Henning; Sassone, Mario SASSONE

    2011-01-01

    engineer may take necessary steps to design robust structures that are insensitive to accidental circumstances. The present paper makes a discussion of such robustness issues related to the future development of reciprocal timber structures. The paper concludes that these kind of structures can have...

  1. Robust dissipativity for uncertain impulsive dynamical systems

    Directory of Open Access Journals (Sweden)

    Liu Bin

    2003-01-01

    Full Text Available We discuss the robust dissipativity with respect to the quadratic supply rate for uncertain impulsive dynamical systems. By employing the Hamilton-Jacobi inequality approach, some sufficient conditions of robust dissipativity for this kind of system are established. Finally, we specialize the obtained results to the case of uncertain linear impulsive dynamical systems.

  2. An Implementation Technique for Multivariate Robust Design

    Institute of Scientific and Technical Information of China (English)

    MA Yi-zhong; ZHAO Feng-yu

    2005-01-01

    This paper investigates systematically the problem of multivariate robust parameter design. First, a measurement criterion for the total variation of multivariate quality characteristics is introduced by the result of information theory. Then the implementation procedure in the robust design is presented. After that, a simulation example from a practical industrial process is provided. Finally, some comments and further work are discussed.

  3. What is it to be sturdy (robust)?

    DEFF Research Database (Denmark)

    Nielsen, Niss Skov; Zwisler, Lars Pagter; Bojsen, Ann Kristina Mikkelsen;

    2015-01-01

    Purpose: This paper intends to give a first insight into the concept of being "sturdy/robust"; To develop and test a Danish model of how to measure sturdi-ness/robustness; To test the scale's ability to identify people in emergency situa-tions who have high risk of developing psychological illness....

  4. Robust fabric substrates for photonic textile applications

    NARCIS (Netherlands)

    Van Pieterson, L.; Bouten, P.C.P.; Kriege, J.C.; Bhattacharya, R.

    2010-01-01

    A fabric substrate is described for electronic textile with robust interwoven connections between the conductive yarns in it. The fabric's robustness, as a function of the electrical reliability of its conductive yarn connections, is shown to hold over large deformations.This fabric is then used to

  5. Robust identification for rational fractional transfer functions

    Institute of Scientific and Technical Information of China (English)

    王书宁

    1997-01-01

    An algorithm is proposed for robust identification of a rational fractional transfer function with a fixed degree under the framework of worst-case/deterministic robust identification. The convergence of the algorithm is proven. Its feasibility is shown with a numerical example.

  6. A Novel Robust Adaptive Fuzzy Controller

    Institute of Scientific and Technical Information of China (English)

    LIU Xiao-hua; WANG Xiu-hong; FEN En-min

    2002-01-01

    For a class of continuous-time nonlinear system, a novel robust adaptive fuzzy controller is proposed by using of Lyapunov method. It is proven that the control algorithm is globally stable, the output tracking-error can convergence to a domain of zero under the assumptions. As a result, the system controlled has stronger robustness for disturbance and modeling error.

  7. Adaptively robust filtering with classified adaptive factors

    Institute of Scientific and Technical Information of China (English)

    CUI Xianqiang; YANG Yuanxi

    2006-01-01

    The key problems in applying the adaptively robust filtering to navigation are to establish an equivalent weight matrix for the measurements and a suitable adaptive factor for balancing the contributions of the measurements and the predicted state information to the state parameter estimates. In this paper, an adaptively robust filtering with classified adaptive factors was proposed, based on the principles of the adaptively robust filtering and bi-factor robust estimation for correlated observations. According to the constant velocity model of Kalman filtering, the state parameter vector was divided into two groups, namely position and velocity. The estimator of the adaptively robust filtering with classified adaptive factors was derived, and the calculation expressions of the classified adaptive factors were presented. Test results show that the adaptively robust filtering with classified adaptive factors is not only robust in controlling the measurement outliers and the kinematic state disturbing but also reasonable in balancing the contributions of the predicted position and velocity, respectively, and its filtering accuracy is superior to the adaptively robust filter with single adaptive factor based on the discrepancy of the predicted position or the predicted velocity.

  8. Security and robustness for collaborative monitors

    NARCIS (Netherlands)

    Testerink, Bas; Bulling, Nils; Dastani, Mehdi

    2016-01-01

    Decentralized monitors can be subject to robustness and security risks. Robustness risks include attacks on the monitor’s infrastructure in order to disable parts of its functionality. Security risks include attacks that try to extract information from the monitor and thereby possibly leak sensitive

  9. Assessment of Process Robustness for Mass Customization

    DEFF Research Database (Denmark)

    Nielsen, Kjeld; Brunø, Thomas Ditlev

    2013-01-01

    robustness and their capability to develop it. Through literature study and analysis of robust process design characteristics a number of metrics are described which can be used for assessment. The metrics are evaluated and analyzed to be applied as KPI’s to help MC companies prioritize efforts in business...

  10. Non-probabilistic Robust Optimal Design Method

    Institute of Scientific and Technical Information of China (English)

    SUN Wei; XU Huanwei; ZHANG Xu

    2009-01-01

    For the purpose of dealing with uncertainty factors in engineering optimization problems, this paper presents a new non-probabilistic robust optimal design method based on maximum variation estimation. The method analyzes the effect of uncertain factors to objective and constraints functions, and then the maximal variations to a solution are calculated. In order to guarantee robust feasibility the maximal variations of constraints are added to original constraints as penalty term; the maximal variation of objective function is taken as a robust index to a solution; linear physical programming is used to adjust the values of quality characteristic and quality variation, and then a bi-level mathematical robust optimal model is coustructed. The method does not require presumed probability distribution of uncertain factors or continuous and differentiable of objective and constraints functions. To demonstrate the proposed method, the design of the two-bar structure acted by concentrated load is presented. In the example the robustness of the normal stress, feasibility of the total volume and the buckling stress are studied. The robust optimal design results show that in the condition of maintaining feasibility robustness, the proposed approach can obtain a robust solution which the designer is satisfied with the value of objective function and its variation.

  11. Offering Adequate Pedagogical Progression via Mobile Equipments-Experiment of a French Engineering School

    Institute of Scientific and Technical Information of China (English)

    Jean-Luc Koning

    2006-01-01

    Students may enter our 5-year engineering school in France at two levels: first and third year.However, due to their quite different backgrounds (this is especially true for third year students), we need to provide newcomers with a 6-week training period during which they follow classes in the fields where they particularly feel weak. Unfortunately, depending on the student' s background, this is not always possible to bring him/her to the expected level. Another aspect one needs to mention is that these students may not have the same weaknesses in a given field. However, for economical reasons, those classes follow a uniform program as it is not feasible to provide a customized progression. In this paper we discuss how to redesign a mathematics course so as to offer tailored exercise sequencing.Groups of 20 students could then draw their exercises from an intranet database according to their previously completed work, try to solve it by themselves, request additional hints and even ask for some direct help from the teacher. Such a database is currently under development. If it turns out several students stumble against the same difficulty the teacher could show the whole class room how to solve it using the digital projector.This project goes one step further than our initial mobile education project ( 2003 ~ 2004 ). Until recently,we had used the equipment in a unique direction, from the instructor toward the students. Here, in this new project we are focusing on the whole loop in order to offer a more adequate (personalized) pedagogical progression: from the student to the teacher (when the tablet PCs are monitored by the teacher) , and back to-ward the students (when a direct help is proded by the teacher)

  12. Adequate image quality with reduced radiation dose in prospectively triggered coronary CTA compared with retrospective techniques

    Energy Technology Data Exchange (ETDEWEB)

    Arnoldi, Elisabeth; Johnson, Thorsten R.; Rist, Carsten; Wintersperger, Bernd J.; Sommer, Wieland H.; Becker, Christoph R.; Reiser, Maximilian F.; Nikolaou, Konstantin [Ludwig-Maximilians University, Department of Clinical Radiology, University Hospitals Munich - Grosshadern Campus, Munich (Germany); Becker, Alexander [Ludwig-Maximilians University, Department of Medicine I, University Hospitals Munich - Grosshadern Campus, Munich (Germany)

    2009-09-15

    The goal of our study was to compare a prospective triggering (PT) CT technique with retrospectively gated (RG) CT techniques in coronary computed tomographic angiograms (CCTA) with respect to image quality and radiation dose. Sixty consecutive patients were enrolled. CCTAs using the RG technique were obtained with a dual-source 64-slice CT system in 40 patients, using ECG-triggered tube current modulation, with either a broad pulsing window at 30-80% of the RR interval (group RGb, 20 patients, heart rate > 70 bpm) or a small pulsing window at 70% (group RGs, 20 patients, heart rate < 70 bpm). The other 20 patients underwent CCTA using the PT technique on a 128-slice CT system (group PT, heart rate < 70 bpm). All images were evaluated by two observers for quality on a three-point scale, with 1 being excellent and 3 being insufficient. The effective radiation dose was calculated for each patient. The average image quality score was 1.5 {+-} 0.6 for PT, 1.35 {+-} 0.5 for RGs and 1.65 {+-} 0.5 for RGb. The mean effective dose for RGb was 9 {+-} 4 mSv, for RGs 7 {+-} 3 mSv and for PT 3 {+-} 1 mSv. This represents a 57% dose reduction for PT compared with RGs and a 67% dose reduction for PT compared with RGb. In conclusion, in selected patients CCTA with the PT technique offers adequate image quality with a significantly lower radiation dose compared with CCTA using RG techniques. (orig.)

  13. Do Foley catheters adequately drain the bladder? Evidence from CT imaging studies

    Energy Technology Data Exchange (ETDEWEB)

    Avulova, Svetlana; Li, Valery J.; Khusid, Johnathan A. [Department of Urology, SUNY Downstate College of Medicine, Brooklyn, NY (United States); Choi, Woo S. [Radiology, SUNY Downstate College of Medicine, Brooklyn, NY (United States); Weiss, Jeffrey P., E-mail: johnathan.khusid@downstate.edu [Department of Urology, Weill Cornell Medical College, New York, NY (United States)

    2015-05-15

    Introduction: The Foley catheter has been widely assumed to be an effective means of draining the bladder. However, recent studies have brought into question its efficacy. The objective of our study is to further assess the adequacy of Foley catheter for complete drainage of the bladder. Materials and Methods: Consecutive catheterized patients were identified from a retrospective review of contrast enhanced and non-contrast enhanced computed tomographic (CT) abdomen and pelvis studies completed from 7/1/2011-6/30/2012. Residual urine volume (RUV) was measured using 5mm axial CT sections as follows: The length (L) and width (W) of the bladder in the section with the greatest cross sectional area was combined with bladder height (H) as determined by multiplanar reformatted images in order to calculate RUV by applying the formula for the volume (V) of a sphere in a cube:V=(π/6)⁎L⁎W⁎H). Results: RUVs of 167 (mean age 67) consecutively catheterized men (n=72) and women (n=95) identified by CT abdomen and pelvis studies were calculated. The mean RUV was 13.2 mL (range: 0.0 mL-859.1 mL, standard deviation: 75.9 mL, margin of error at 95% confidence:11.6 mL). Four (2.4%) catheterized patients had RUVs of >50 mL, two of whom had an improperly placed catheter tip noted on their CT-reports. Conclusions: Previous studies have shown that up to 43% of catheterized patients had a RUV greater than 50 mL, suggesting inadequacy of bladder drainage via the Foley catheter. Our study indicated that the vast majority of patients with Foley catheters (97.6%), had adequately drained bladders with volumes of <50 mL. (author)

  14. Prevention of mother to child transmission lay counsellors: Are they adequately trained?

    Directory of Open Access Journals (Sweden)

    Catherine H. Thurling

    2012-05-01

    Full Text Available South Africa’s high prevalence of human immunodeficiency virus (HIV infected women requires a comprehensive health care approach to pregnancy because of the added risk of their HIV status. As a result of the shortage of health care workers in South Africa, lay counsellors play important roles in the prevention of mother to child transmission of HIV (PMTCT.There is no standardization of training of lay counsellors in South Africa, and training varies in length depending on the training organisation.The study aimed to investigate the training of lay counsellors by analysing their training curricula and interviewing lay counsellors about their perceptions of their training.A two phase research method was applied. Phase one documented an analysis of the training curricula. Phase two was semi-structured interviews with the participants. Purposive sampling was undertaken for this study. The total sample size was 13 people, with a final sample of 9 participants, determined at the point of data saturation.The research was qualitative, descriptive and contextual in design. The curricula analysed had different styles of delivery, and the approaches to learning and courses varied, resulting in inconsistent training outcomes. A need for supervision and mentorship in the working environment was also noted.The training of lay counsellors needs to be adapted to meet the extended roles that they are playing in PMTCT. The standardization of training programmes, and the incorporation of a system of mentorship in the work environment, would ensure that the lay counsellors are adequately prepared for their role in PMTCT.

  15. Ensuring Adequate Health and Safety Information for Decision Makers during Large-Scale Chemical Releases

    Science.gov (United States)

    Petropoulos, Z.; Clavin, C.; Zuckerman, B.

    2015-12-01

    The 2014 4-Methylcyclohexanemethanol (MCHM) spill in the Elk River of West Virginia highlighted existing gaps in emergency planning for, and response to, large-scale chemical releases in the United States. The Emergency Planning and Community Right-to-Know Act requires that facilities with hazardous substances provide Material Safety Data Sheets (MSDSs), which contain health and safety information on the hazardous substances. The MSDS produced by Eastman Chemical Company, the manufacturer of MCHM, listed "no data available" for various human toxicity subcategories, such as reproductive toxicity and carcinogenicity. As a result of incomplete toxicity data, the public and media received conflicting messages on the safety of the contaminated water from government officials, industry, and the public health community. Two days after the governor lifted the ban on water use, the health department partially retracted the ban by warning pregnant women to continue avoiding the contaminated water, which the Centers for Disease Control and Prevention deemed safe three weeks later. The response in West Virginia represents a failure in risk communication and calls to question if government officials have sufficient information to support evidence-based decisions during future incidents. Research capabilities, like the National Science Foundation RAPID funding, can provide a solution to some of the data gaps, such as information on environmental fate in the case of the MCHM spill. In order to inform policy discussions on this issue, a methodology for assessing the outcomes of RAPID and similar National Institutes of Health grants in the context of emergency response is employed to examine the efficacy of research-based capabilities in enhancing public health decision making capacity. The results of this assessment highlight potential roles rapid scientific research can fill in ensuring adequate health and safety data is readily available for decision makers during large

  16. Environmental change makes robust ecological networks fragile

    Science.gov (United States)

    Strona, Giovanni; Lafferty, Kevin D.

    2016-01-01

    Complex ecological networks appear robust to primary extinctions, possibly due to consumers’ tendency to specialize on dependable (available and persistent) resources. However, modifications to the conditions under which the network has evolved might alter resource dependability. Here, we ask whether adaptation to historical conditions can increase community robustness, and whether such robustness can protect communities from collapse when conditions change. Using artificial life simulations, we first evolved digital consumer-resource networks that we subsequently subjected to rapid environmental change. We then investigated how empirical host–parasite networks would respond to historical, random and expected extinction sequences. In both the cases, networks were far more robust to historical conditions than new ones, suggesting that new environmental challenges, as expected under global change, might collapse otherwise robust natural ecosystems.

  17. International Conference on Robust Statistics 2015

    CERN Document Server

    Basu, Ayanendranath; Filzmoser, Peter; Mukherjee, Diganta

    2016-01-01

    This book offers a collection of recent contributions and emerging ideas in the areas of robust statistics presented at the International Conference on Robust Statistics 2015 (ICORS 2015) held in Kolkata during 12–16 January, 2015. The book explores the applicability of robust methods in other non-traditional areas which includes the use of new techniques such as skew and mixture of skew distributions, scaled Bregman divergences, and multilevel functional data methods; application areas being circular data models and prediction of mortality and life expectancy. The contributions are of both theoretical as well as applied in nature. Robust statistics is a relatively young branch of statistical sciences that is rapidly emerging as the bedrock of statistical analysis in the 21st century due to its flexible nature and wide scope. Robust statistics supports the application of parametric and other inference techniques over a broader domain than the strictly interpreted model scenarios employed in classical statis...

  18. Danish Requirements for Robustness of Structures

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Christensen, H. H.

    2006-01-01

    Increased use of advanced types of structures with limited redundancy and serious failure consequences combined with strengthened requirements to efficiency in design and execution as well as increased risk of human errors necessitates requirements for the robustness of new structures, essential....... This paper describes the background of the revised robustness requirements implemented in the Danish Code of Practice for Safety of Structures in 2003 [1, 2, 3]. According to the Danish design rules robustness shall be documented for all structures where consequences of failure are serious. This paper...... systems and identification of key elements. Step 3: evaluation of the sensitivity of essential parts of the structure to unintentional loads and defects. Step 4: documentation of robustness by 'failure of key element' analysis. Step 5: documentation of robustness by increasing the strength of key elements...

  19. Boolean networks with robust and reliable trajectories

    Energy Technology Data Exchange (ETDEWEB)

    Schmal, Christoph; Peixoto, Tiago P; Drossel, Barbara, E-mail: schmal@physik.uni-bielefeld.d, E-mail: tiago@fkp.tu-darmstadt.d, E-mail: drossel@fkp.tu-darmstadt.d [Institut fuer Festkoerperphysik, TU Darmstadt, Hochschulstrasse 6, 64289 Darmstadt (Germany)

    2010-11-15

    We construct and investigate Boolean networks that follow a given reliable trajectory in state space, which is insensitive to fluctuations in the updating schedule and which is also robust against noise. Robustness is quantified as the probability that the dynamics return to the reliable trajectory after a perturbation of the state of a single node. In order to achieve high robustness, we navigate through the space of possible update functions by using an evolutionary algorithm. We constrain the networks to those having the minimum number of connections required to obtain the reliable trajectory. Surprisingly, we find that robustness always reaches values close to 100% during the evolutionary optimization process. The set of update functions can be evolved such that it differs only slightly from that of networks that were not optimized with respect to robustness. The state space of the optimized networks is dominated by the basin of attraction of the reliable trajectory.

  20. The Best Performing Cilium: Efficient or Robust?

    CERN Document Server

    Guo, Hanliang

    2015-01-01

    Motile cilia are used by many eukaryotic cells to transport flow. Cilia-driven flows are important to many physiological functions, yet a deep understanding of the interplay between the mechanical structure of cilia and their physiological functions in healthy and diseased conditions remains elusive. For developing such understanding, one needs a quantitative framework for assessing cilia performance and robustness when subject to perturbations in the cilia apparatus. Here, we link cilia design (beating patterns) to function (flow transport) in the context of experimentally- and theoretically-derived cilia models. We particularly examine the optimality and robustness of cilia design. Optimality refers to efficiency of flow transport, while robustness is defined as low sensitivity to variations in the design parameters. We find that suboptimal designs can be more robust than optimal ones. That is, designing for the most efficient cilium does not guarantee robustness. These findings have significant implication...

  1. Global Uranium And Thorium Resources: Are They Adequate To Satisfy Demand Over The Next Half Century?

    Science.gov (United States)

    Lambert, I. B.

    2012-04-01

    This presentation will consider the adequacy of global uranium and thorium resources to meet realistic nuclear power demand scenarios over the next half century. It is presented on behalf of, and based on evaluations by, the Uranium Group - a joint initiative of the OECD Nuclear Energy Agency and the International Atomic Energy Agency, of which the author is a Vice Chair. The Uranium Group produces a biennial report on Uranium Resources, Production and Demand based on information from some 40 countries involved in the nuclear fuel cycle, which also briefly reviews thorium resources. Uranium: In 2008, world production of uranium amounted to almost 44,000 tonnes (tU). This supplied approximately three-quarters of world reactor requirements (approx. 59,000 tU), the remainder being met by previously mined uranium (so-called secondary sources). Information on availability of secondary sources - which include uranium from excess inventories, dismantling nuclear warheads, tails and spent fuel reprocessing - is incomplete, but such sources are expected to decrease in market importance after 2013. In 2008, the total world Reasonably Assured plus Inferred Resources of uranium (recoverable at less than 130/kgU) amounted to 5.4 million tonnes. In addition, it is clear that there are vast amounts of uranium recoverable at higher costs in known deposits, plus many as yet undiscovered deposits. The Uranium Group has concluded that the uranium resource base is more than adequate to meet projected high-case requirements for nuclear power for at least half a century. This conclusion does not assume increasing replacement of uranium by fuels from reprocessing current reactor wastes, or by thorium, nor greater reactor efficiencies, which are likely to ameliorate future uranium demand. However, progressively increasing quantities of uranium will need to be mined, against a backdrop of the relatively small number of producing facilities around the world, geopolitical uncertainties and

  2. Biological Robustness: Paradigms, Mechanisms, and Systems Principles

    Directory of Open Access Journals (Sweden)

    James Michael Whitacre

    2012-05-01

    Full Text Available Robustness has been studied through the analysis of data sets, simulations, and a variety of experimental techniques that each have their own limitations but together confirm the ubiquity of biological robustness. Recent trends suggest that different types of perturbation (e.g. mutational, environmental are commonly stabilized by similar mechanisms, and system sensitivities often display a long-tailed distribution with relatively few perturbations representing the majority of sensitivities. Conceptual paradigms from network theory, control theory, complexity science, and natural selection have been used to understand robustness, however each paradigm has a limited scope of applicability and there has been little discussion of the conditions that determine this scope or the relationships between paradigms. Systems properties such as modularity, bow-tie architectures, degeneracy, and other topological features are often positively associated with robust traits, however common underlying mechanisms are rarely mentioned. For instance, many system properties support robustness through functional redundancy or through response diversity with responses regulated by competitive exclusion and cooperative facilitation. Moreover, few studies compare and contrast alternative strategies for achieving robustness such as homeostasis, adaptive plasticity, environment shaping, and environment tracking. These strategies share similarities in their utilization of adaptive and self-organization processes that are not well appreciated yet might be suggestive of reusable building blocks for generating robust behavior.

  3. Robust Multiobjective Controllability of Complex Neuronal Networks.

    Science.gov (United States)

    Tang, Yang; Gao, Huijun; Du, Wei; Lu, Jianquan; Vasilakos, Athanasios V; Kurths, Jurgen

    2016-01-01

    This paper addresses robust multiobjective identification of driver nodes in the neuronal network of a cat's brain, in which uncertainties in determination of driver nodes and control gains are considered. A framework for robust multiobjective controllability is proposed by introducing interval uncertainties and optimization algorithms. By appropriate definitions of robust multiobjective controllability, a robust nondominated sorting adaptive differential evolution (NSJaDE) is presented by means of the nondominated sorting mechanism and the adaptive differential evolution (JaDE). The simulation experimental results illustrate the satisfactory performance of NSJaDE for robust multiobjective controllability, in comparison with six statistical methods and two multiobjective evolutionary algorithms (MOEAs): nondominated sorting genetic algorithms II (NSGA-II) and nondominated sorting composite differential evolution. It is revealed that the existence of uncertainties in choosing driver nodes and designing control gains heavily affects the controllability of neuronal networks. We also unveil that driver nodes play a more drastic role than control gains in robust controllability. The developed NSJaDE and obtained results will shed light on the understanding of robustness in controlling realistic complex networks such as transportation networks, power grid networks, biological networks, etc.

  4. Performance of a grid-connected wind generation system with a robust susceptance controller

    Energy Technology Data Exchange (ETDEWEB)

    Rahim, A.H.M.A. [Department of Electrical Engineering, K.F. University of Petroleum and Minerals, KFUPM Box 349, Dhahran 31261 (Saudi Arabia); Nowicki, E.P. [Department of Electrical and Computer Engineering, University of Calgary, Calgary, AB (Canada)

    2011-01-15

    Wind turbine driven induction generators are vulnerable to transient disturbances like wind gusts and low voltages on the system. The fixed capacitor at the generator terminal or the limited support from the grid may not be able to provide the requisite reactive power under these abnormal conditions. This paper presents a susceptance control strategy for a variable speed wound-rotor induction generator which can cater for the reactive power requirement. The susceptance is adjusted through a robust feedback controller included in the terminal voltage driven automatic excitation control circuit. The fixed parameter robust controller design is carried out in frequency domain using multiplicative uncertainty modeling and H{sub {infinity}} norms. The robustness of the controller has been evaluated through optimally tuned PID controllers. Simulation results show that the robust controller can effectively restore normal operation following emergencies like sudden load changes, wind gusts and low voltage conditions. The proposed robust controller has been shown to have adequate fault ride through capabilities in order to be able to meet connection requirements defined by transmission system operators. (author)

  5. Towards distortion-free robust image authentication

    Energy Technology Data Exchange (ETDEWEB)

    Coltuc, D [EE Department, Valahia University Targoviste (Romania)

    2007-07-15

    This paper investigates a general framework for distortion-free robust image authentication by multiple marking. First, by robust watermarking a subsampled version of image edges is embedded. Then, by reversible watermarking the information needed to recover the original image is inserted, too. The hiding capacity of the reversible watermarking is the essential requirement for this approach. Thus in case of no attacks not only image is authenticated but also the original is exactly recovered. In case of attacks, reversibility is lost, but image can still be authenticated. Preliminary results providing very good robustness against JPEG compression are presented.

  6. Robust control of an aircraft model

    Energy Technology Data Exchange (ETDEWEB)

    Werner, H. [Bochum Univ. (Germany). Fakultaet fuer Elektrotechnik

    1999-12-01

    A new multimodel approach to robust controller design is illustrated by a practical application: for a laboratory aircraft model, a robust controller is designed simultaneously for normal operating conditions and for propeller failure. Based on a linear model for each operating mode, an LMI formulation of the problem and convex programming are used to search for a state feedback controller which achieves the objective. This state feedback design is then realized simultaneously in both operating modes by a controller which is based on fast output sampling. Robust performance is demonstrated by experimental results. (orig.)

  7. Robust control of an aircraft model

    Energy Technology Data Exchange (ETDEWEB)

    Werner, H. (Bochum Univ. (Germany). Fakultaet fuer Elektrotechnik)

    1999-01-01

    A new multimodel approach to robust controller design is illustrated by a practical application: for a laboratory aircraft model, a robust controller is designed simultaneously for normal operating conditions and for propeller failure. Based on a linear model for each operating mode, an LMI formulation of the problem and convex programming are used to search for a state feedback controller which achieves the objective. This state feedback design is then realized simultaneously in both operating modes by a controller which is based on fast output sampling. Robust performance is demonstrated by experimental results. (orig.)

  8. Robust recognition via information theoretic learning

    CERN Document Server

    He, Ran; Yuan, Xiaotong; Wang, Liang

    2014-01-01

    This Springer Brief represents a comprehensive review of information theoretic methods for robust recognition. A variety of information theoretic methods have been proffered in the past decade, in a large variety of computer vision applications; this work brings them together, attempts to impart the theory, optimization and usage of information entropy.The?authors?resort to a new information theoretic concept, correntropy, as a robust measure and apply it to solve robust face recognition and object recognition problems. For computational efficiency,?the brief?introduces the additive and multip

  9. Design Robust Controller for Rotary Kiln

    Directory of Open Access Journals (Sweden)

    Omar D. Hernández-Arboleda

    2013-11-01

    Full Text Available This paper presents the design of a robust controller for a rotary kiln. The designed controller is a combination of a fractional PID and linear quadratic regulator (LQR, these are not used to control the kiln until now, in addition robustness criteria are evaluated (gain margin, phase margin, strength gain, rejecting high frequency noise and sensitivity applied to the entire model (controller-plant, obtaining good results with a frequency range of 0.020 to 90 rad/s, which contributes to the robustness of the system.

  10. Robustness of Distance-to-Default

    DEFF Research Database (Denmark)

    Jessen, Cathrine; Lando, David

    2013-01-01

    Distance-to-default is a remarkably robust measure for ranking firms according to their risk of default. The ranking seems to work despite the fact that the Merton model from which the measure is derived produces default probabilities that are far too small when applied to real data. We use...... simulations to investigate the robustness of the distance-to-default measure to different model specifications. Overall we find distance-to-default to be robust to a number of deviations from the simple Merton model that involve different asset value dynamics and different default triggering mechanisms...

  11. Robust Spectral Estimation of Track Irregularity

    Institute of Scientific and Technical Information of China (English)

    Fu Wenjuan; Chen Chunjun

    2005-01-01

    Because the existing spectral estimation methods for railway track irregularity analysis are very sensitive to outliers, a robust spectral estimation method is presented to process track irregularity signals. The proposed robust method is verified using 100 groups of clean/contaminated data reflecting he vertical profile irregularity taken from Bejing-Guangzhou railway with a sampling frequency of 33 data every 10 m, and compared with the Auto Regressive (AR) model. The experimental results show that the proposed robust estimation is resistible to noise and insensitive to outliers, and is superior to the AR model in terms of efficiency, stability and reliability.

  12. Modeling and robust control of wind turbine

    Science.gov (United States)

    Gilev, Bogdan

    2016-12-01

    In this paper a model of a wind turbine is evaluated, consisting of: wind speed model, mechanical and electrical model of generator and tower oscillation model. This model is linearized around of a nominal point. By using the linear model with uncertainties is synthesized a uncertain model. By using the uncertain model and robust control theory is developed a robust controller, which provide mode of stabilizing the rotor frequency and damping the tower oscillations. Finally is simulated work of nonlinear system and robust controller

  13. Robust Structured Control Design via LMI Optimization

    DEFF Research Database (Denmark)

    Adegas, Fabiano Daher; Stoustrup, Jakob

    2011-01-01

    This paper presents a new procedure for discrete-time robust structured control design. Parameter-dependent nonconvex conditions for stabilizable and induced L2-norm performance controllers are solved by an iterative linear matrix inequalities (LMI) optimization. A wide class of controller...... structures including decentralized of any order, fixed-order dynamic output feedback, static output feedback can be designed robust to polytopic uncertainties. Stability is proven by a parameter-dependent Lyapunov function. Numerical examples on robust stability margins shows that the proposed procedure can...

  14. Robust optimisation of railway crossing geometry

    Science.gov (United States)

    Wan, Chang; Markine, Valeri; Dollevoet, Rolf

    2016-05-01

    This paper presents a methodology for improving the crossing (frog) geometry through the robust optimisation approach, wherein the variability of the design parameters within a prescribed tolerance is included in the optimisation problem. Here, the crossing geometry is defined by parameterising the B-spline represented cross-sectional shape and the longitudinal height profile of the nose rail. The dynamic performance of the crossing is evaluated considering the variation of wheel profiles and track alignment. A multipoint approximation method (MAM) is applied in solving the optimisation problem of minimising the contact pressure during the wheel-rail contact and constraining the location of wheel transition at the crossing. To clarify the difference between the robust optimisation and the normal deterministic optimisation approaches, the optimisation problems are solved in both approaches. The results show that the deterministic optimum fails under slight change of the design variables; the robust optimum, however, has improved and robust performance.

  15. Robust resource allocation in future wireless networks

    CERN Document Server

    Parsaeefard, Saeedeh; Mokari, Nader

    2017-01-01

    This book presents state-of-the-art research on robust resource allocation in current and future wireless networks. The authors describe the nominal resource allocation problems in wireless networks and explain why introducing robustness in such networks is desirable. Then, depending on the objectives of the problem, namely maximizing the social utility or the per-user utility, cooperative or competitive approaches are explained and their corresponding robust problems are considered in detail. For each approach, the costs and benefits of robust schemes are discussed and the algorithms for reducing their costs and improving their benefits are presented. Considering the fact that such problems are inherently non-convex and intractable, a taxonomy of different relaxation techniques is presented, and applications of such techniques are shown via several examples throughout the book. Finally, the authors argue that resource allocation continues to be an important issue in future wireless networks, and propose spec...

  16. Robust integral stabilization of regular linear systems

    Institute of Scientific and Technical Information of China (English)

    XU Chengzheng; FENG Dexing

    2004-01-01

    We consider regular systems with control and observation. We prove some necessary and sufficient condition for an exponentially stable regular system to admit an integral stabilizing controller. We propose also some robust integral controllers when they exist.

  17. Robust optical delay lines via topological protection

    CERN Document Server

    Hafezi, Mohammad; Lukin, Mikhail; Taylor, Jacob

    2011-01-01

    Phenomena associated with topological properties of physical systems are naturally robust against perturbations. This robustness is exemplified by quantized conductance and edge state transport in the quantum Hall and quantum spin Hall effects. Here we show how exploiting topological properties of optical systems can be used to implement robust photonic devices. We demonstrate how quantum spin Hall Hamiltonians can be created with linear optical elements using a network of coupled resonator optical waveguides (CROW) in two dimensions. We find that key features of quantum Hall systems, including the characteristic Hofstadter butterfly and robust edge state transport, can be obtained in such systems. As a specific application, we show that the topological protection can be used to dramatically improve the performance of optical delay lines and to overcome limitations related to disorder in photonic technologies.

  18. Robust facial expression recognition via compressive sensing.

    Science.gov (United States)

    Zhang, Shiqing; Zhao, Xiaoming; Lei, Bicheng

    2012-01-01

    Recently, compressive sensing (CS) has attracted increasing attention in the areas of signal processing, computer vision and pattern recognition. In this paper, a new method based on the CS theory is presented for robust facial expression recognition. The CS theory is used to construct a sparse representation classifier (SRC). The effectiveness and robustness of the SRC method is investigated on clean and occluded facial expression images. Three typical facial features, i.e., the raw pixels, Gabor wavelets representation and local binary patterns (LBP), are extracted to evaluate the performance of the SRC method. Compared with the nearest neighbor (NN), linear support vector machines (SVM) and the nearest subspace (NS), experimental results on the popular Cohn-Kanade facial expression database demonstrate that the SRC method obtains better performance and stronger robustness to corruption and occlusion on robust facial expression recognition tasks.

  19. Review of Robust Video Watermarking Algorithms

    CERN Document Server

    Deshpande, Neeta; Manthalkar, R

    2010-01-01

    There has been a remarkable increase in the data exchange over web and the widespread use of digital media. As a result, multimedia data transfers also had a boost up. The mounting interest with reference to digital watermarking throughout the last decade is certainly due to the increase in the need of copyright protection of digital content. This is also enhanced due to commercial prospective. Applications of video watermarking in copy control, broadcast monitoring, fingerprinting, video authentication, copyright protection etc is immensely rising. The main aspects of information hiding are capacity, security and robustness. Capacity deals with the amount of information that can be hidden. The skill of anyone detecting the information is security and robustness refers to the resistance to modification of the cover content before concealed information is destroyed. Video watermarking algorithms normally prefers robustness. In a robust algorithm it is not possible to eliminate the watermark without rigorous de...

  20. Evaluating Biological Robustness of Innovative Management Alternatives

    NARCIS (Netherlands)

    Bastardie, F.; Baudron, A.; Bilocca, R.; Boje, J.; Bult, T.P.; Garcia, D.; Hintzen, N.T.

    2009-01-01

    The influence of innovative management alternatives (participatory governance, effort management, decision rules) on biological robustness (BR) in various fisheries relevant to the EU (Baltic, Western Shelf, Faroe Islands, North Sea), was investigated with a numerical simulation model developed in t

  1. The structural robustness of multiprocessor computing system

    Directory of Open Access Journals (Sweden)

    N. Andronaty

    1996-03-01

    Full Text Available The model of the multiprocessor computing system on the base of transputers which permits to resolve the question of valuation of a structural robustness (viability, survivability is described.

  2. Robust and Efficient Parametric Face Alignment

    NARCIS (Netherlands)

    Tzimiropoulos, Georgios; Zafeiriou, Stefanos; Pantic, Maja

    2011-01-01

    We propose a correlation-based approach to parametric object alignment particularly suitable for face analysis applications which require efficiency and robustness against occlusions and illumination changes. Our algorithm registers two images by iteratively maximizing their correlation coefficient

  3. Framework for Robustness Assessment of Timber Structures

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2011-01-01

    to efficiency in design and execution followed by increased risk of human errors has made the need of requirements to robustness of new structures essential. Further, the collapse of the Ballerup Super Arena, the bad Reichenhall Ice-Arena and a number of other structural systems during the last 10 years has......This paper presents a theoretical framework for the design and analysis of robustness of timber structures. This is actualized by a more4 frequent use of advanced types of timber structures with limited redundancy and serious consequences in the case of failure. Combined with increased requirements...... increased the interest in robustness. Typically, modern structural design codes require that ‘the consequence of damages to structures should not be disproportional to the causes of the damages’. However, although the importance of robustness for structural design is widely recognized, the code requirements...

  4. A Miniaturized and Robust FTS Sensor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Vescent Photonics details a miniaturized and robust Fourier transform spectrometer(FTS) for in-situ chemical and spectral analysis. Phase I research will focus on...

  5. A Miniaturized and Robust FTS Sensor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Vescent Photonics determined the feasibility of a miniaturized, robust, Fourier transform spectrometer (FTS) for either in-situ or remote chemical and spectral...

  6. Bypass rewiring and robustness of complex networks

    Science.gov (United States)

    Park, Junsang; Hahn, Sang Geun

    2016-08-01

    A concept of bypass rewiring is introduced, and random bypass rewiring is analytically and numerically investigated with simulations. Our results show that bypass rewiring makes networks robust against removal of nodes including random failures and attacks. In particular, random bypass rewiring connects all nodes except the removed nodes on an even degree infinite network and makes the percolation threshold 0 for arbitrary occupation probabilities. In our example, the even degree network is more robust than the original network with random bypass rewiring, while the original network is more robust than the even degree networks without random bypass. We propose a greedy bypass rewiring algorithm which guarantees the maximum size of the largest component at each step, assuming which node will be removed next is unknown. The simulation result shows that the greedy bypass rewiring algorithm improves the robustness of the autonomous system of the Internet under attacks more than random bypass rewiring.

  7. Bypass Rewiring and Robustness of Complex Networks

    CERN Document Server

    Park, Junsang

    2016-01-01

    A concept of bypass rewiring is introduced and random bypass rewiring is analytically and numerically investigated with simulations. Our results show that bypass rewiring makes networks robust against removal of nodes including random failures and attacks. Especially, random bypass rewiring connects all nodes except the removed nodes on an even degree infinite network and makes the percolation threshold $0$ for arbitrary occupation probabilities. In our example, the even degree network is more robust than the original network with random bypass rewiring while the original network is more robust than the even degree networks without random bypass. We propose a greedy bypass rewiring algorithm which guarantees the maximum size of the largest component at each step, assuming which node will be removed next is unknown. The simulation result shows that the greedy bypass rewiring algorithm improves the robustness of the autonomous system of the Internet under attacks more than random bypass rewiring.

  8. Facilitation may not be an adequate mechanism of community succession on carrion.

    Science.gov (United States)

    Michaud, Jean-Philippe; Moreau, Gaétan

    2017-04-01

    The facilitation model of ecological succession was advanced by plant ecologists in the late 1970s and was then introduced to carrion ecology in the late 1980s, without empirical evidence of its applicability. Ecologists in both disciplines proposed removing early colonists, in this case fly eggs and larvae, from the substrate to determine whether other species could still colonize, which to our knowledge has never been attempted. Here, we tested the facilitation model in a carrion system by removing fly eggs and larvae from carcasses that were exposed in agricultural fields and assigned to one of the following treatment levels of removal intensity: 0, carrion systems. Although results showed, in part, that the removal of fly eggs and larvae decreased the decomposition rate of carcasses, the removal did not prevent colonization by secondary colonizers. Finally, we discuss future studies and make recommendations as to how the facilitation model could be improved, firstly by being more specific about the scale where facilitation is believed to be occurring, secondly by clearly stating what environmental modification is believed to be involved, and thirdly by disentangling facilitation from priority effects.

  9. Robustness of timber structures in seismic areas

    OpenAIRE

    Branco, J. M.

    2011-01-01

    Some of the properties sought in seismic design of buildings are also considered fundamental to guarantee structural robustness. Moreover, some key concepts are common to both seismic and robustness design. In fact, both analyses consider events with a very small probability of occurrence, and consequently, a significant level of damage is admissible. As very rare events,in both cases, the actions are extremely hard to quantify. The acceptance of limited damage requires a system based anal...

  10. Robust Filtering and Smoothing with Gaussian Processes

    OpenAIRE

    Deisenroth, Marc Peter; Turner, Ryan; Huber, Marco F.; Hanebeck, Uwe D.; Rasmussen, Carl Edward

    2012-01-01

    We propose a principled algorithm for robust Bayesian filtering and smoothing in nonlinear stochastic dynamic systems when both the transition function and the measurement function are described by non-parametric Gaussian process (GP) models. GPs are gaining increasing importance in signal processing, machine learning, robotics, and control for representing unknown system functions by posterior probability distributions. This modern way of "system identification" is more robust than finding p...

  11. Planning with Robust (L)RTDP

    OpenAIRE

    Buffet, Olivier; Aberdeen, Douglas

    2004-01-01

    Stochastic Shortest Path problems (SSPs), a subclass of Markov Decision Problems (MDPs), can be efficiently dealt with using Real-Time Dynamic Programming (RTDP). Yet, MDP models are often uncertain (obtained through statistics or guessing). The usual approach is robust planning: searching for the best policy under the worst model. This paper shows how RTDP can be made robust in the common case where transition probabilities are known to lie in a given interval.

  12. Stamping Robust Design Method and Its Application

    Institute of Scientific and Technical Information of China (English)

    Z.Q. Lin; Jian Ai; Weigang Zhang; Shuhui Li

    2004-01-01

    The application of the robust design to stamping is discussed in the paper. The regression equation of the quality index and its influencing factors can be attained by using method of central composite design. Stamping computer simulation takes the place of real stamping experiments to fulfill the special experimental conditions. The real stamping experiments prove the correctness and the feasibility of the stamping robust design method-central composite design.

  13. Problems of robustness for universal coding schemes

    OpenAIRE

    V'yugin, V. V.

    2008-01-01

    The Lempel-Ziv universal coding scheme is asymptotically optimal for the class of all stationary ergodic sources. A problem of robustness of this property under small violations of ergodicity is studied. A notion of deficiency of algorithmic randomness is used as a measure of disagreement between data sequence and probability measure. We prove that universal compressing schemes from a large class are non-robust in the following sense: if the randomness deficiency grows arbitrarily slowly on i...

  14. NASA Early Career Fellowship Program

    Science.gov (United States)

    Smith, H. D.

    2012-12-01

    The Early Career Fellowship program was established in 2005 to facilitate the integration of outstanding early career planetary science researchers into established research funding programs by providing tools and experience useful to maintain a successful research program. Executing a successful research program requires a few key elements such as: successful proposal writing; adequate (paid) research time; management of a laboratory; collaboration and networking; frequent and high-quality publications; and adequate start-up equipment funds. These elements may be particularly critical for early career researchers searching for a tenure- track or equivalent position. The Early Career Fellowship program recognizes the importance of these skills and provides extra funding and resources to begin a successful research program. For consideration into The Early Career Fellowship program, the candidate needs to be the P. I. or Science P.I. of a funded research proposal from one of the participating R&A program areas, be within 7 years of earning a PhD, hold a non-tenure track position, and indicate the early career candidacy when submitting the research proposal. If the research proposal is funded and the discipline scientist nominates the candidate as an early career fellow, the candidate is then considered a Fellow and eligible to propose for Step 2. Upon obtaining a tenure-track equivalent position the Fellow submits a Step 2 proposal for up to one hundred thousand dollars in start-up funds. Start-up funds may be used for salary; undergraduate and/or graduate research assistants; supplies and instrument upgrades; travel to conferences, meetings, and advisory groups; time and travel for learning new skills; publication page charges; books and journal subscriptions; computer time and/or specialized software; and other justified research-specific needs. The early career fellowship program provides resources that a more established scientist would have acquired allowing

  15. Robust geostatistical analysis of spatial data

    Science.gov (United States)

    Papritz, Andreas; Künsch, Hans Rudolf; Schwierz, Cornelia; Stahel, Werner A.

    2013-04-01

    Most of the geostatistical software tools rely on non-robust algorithms. This is unfortunate, because outlying observations are rather the rule than the exception, in particular in environmental data sets. Outliers affect the modelling of the large-scale spatial trend, the estimation of the spatial dependence of the residual variation and the predictions by kriging. Identifying outliers manually is cumbersome and requires expertise because one needs parameter estimates to decide which observation is a potential outlier. Moreover, inference after the rejection of some observations is problematic. A better approach is to use robust algorithms that prevent automatically that outlying observations have undue influence. Former studies on robust geostatistics focused on robust estimation of the sample variogram and ordinary kriging without external drift. Furthermore, Richardson and Welsh (1995) proposed a robustified version of (restricted) maximum likelihood ([RE]ML) estimation for the variance components of a linear mixed model, which was later used by Marchant and Lark (2007) for robust REML estimation of the variogram. We propose here a novel method for robust REML estimation of the variogram of a Gaussian random field that is possibly contaminated by independent errors from a long-tailed distribution. It is based on robustification of estimating equations for the Gaussian REML estimation (Welsh and Richardson, 1997). Besides robust estimates of the parameters of the external drift and of the variogram, the method also provides standard errors for the estimated parameters, robustified kriging predictions at both sampled and non-sampled locations and kriging variances. Apart from presenting our modelling framework, we shall present selected simulation results by which we explored the properties of the new method. This will be complemented by an analysis a data set on heavy metal contamination of the soil in the vicinity of a metal smelter. Marchant, B.P. and Lark, R

  16. Are forestation, bio-char and landfilled biomass adequate offsets for the climate effects of burning fossil fuels?

    NARCIS (Netherlands)

    Reijnders, L.

    2009-01-01

    Forestation and landfilling purpose-grown biomass are not adequate offsets for the CO2 emission from burning fossil fuels. Their permanence is insufficiently guaranteed and landfilling purpose-grown biomass may even be counterproductive. As to permanence, bio-char may do better than forests or landf

  17. Fed up with the right to food? : The Netherlands' policies and practices regarding the human right to adequate food

    NARCIS (Netherlands)

    Hospes, O.; Meulen, van der B.M.J.

    2009-01-01

    There is no one in this world who would deny the importance of access to adequate food for every human being. In fact, access to food has been declared a human right in 1948 with the Universal Declaration of Human Rights. In spite of the right to food to be more than half a century old, many are not

  18. Using Fuzzy Logic to Identify Schools Which May Be Misclassified by the No Child Left Behind Adequate Yearly Progress Policy

    Science.gov (United States)

    Yates, Donald W.

    2009-01-01

    This investigation developed, tested, and prototyped a Fuzzy Inference System (FIS) that would assist decision makers in identifying schools that may have been misclassified by existing Adequate Yearly Progress (AYP) methods. This prototype was then used to evaluate Louisiana elementary schools using published school data for Academic Year 2004. …

  19. The comparison of robust partial least squares regression with robust principal component regression on a real

    Science.gov (United States)

    Polat, Esra; Gunay, Suleyman

    2013-10-01

    One of the problems encountered in Multiple Linear Regression (MLR) is multicollinearity, which causes the overestimation of the regression parameters and increase of the variance of these parameters. Hence, in case of multicollinearity presents, biased estimation procedures such as classical Principal Component Regression (CPCR) and Partial Least Squares Regression (PLSR) are then performed. SIMPLS algorithm is the leading PLSR algorithm because of its speed, efficiency and results are easier to interpret. However, both of the CPCR and SIMPLS yield very unreliable results when the data set contains outlying observations. Therefore, Hubert and Vanden Branden (2003) have been presented a robust PCR (RPCR) method and a robust PLSR (RPLSR) method called RSIMPLS. In RPCR, firstly, a robust Principal Component Analysis (PCA) method for high-dimensional data on the independent variables is applied, then, the dependent variables are regressed on the scores using a robust regression method. RSIMPLS has been constructed from a robust covariance matrix for high-dimensional data and robust linear regression. The purpose of this study is to show the usage of RPCR and RSIMPLS methods on an econometric data set, hence, making a comparison of two methods on an inflation model of Turkey. The considered methods have been compared in terms of predictive ability and goodness of fit by using a robust Root Mean Squared Error of Cross-validation (R-RMSECV), a robust R2 value and Robust Component Selection (RCS) statistic.

  20. AUDIOMETRY-FIRST STEP TO EARLY DETECTION

    Directory of Open Access Journals (Sweden)

    Slavco CADIEV

    1997-09-01

    Full Text Available The problem of early detection of children with sense of hearing is very complicate. If the damage of sense of hearing is not detected on time and if You don’t take adequate treatment, after seven year that is impossible. Audiometry is one step to reestablishment diagnostic with help of electronic technology.

  1. Hypotheses testing for fuzzy robust regression parameters

    Energy Technology Data Exchange (ETDEWEB)

    Kula, Kamile Sanli [Ahi Evran University, Department of Mathematics, 40200 Kirsehir (Turkey)], E-mail: sanli2004@hotmail.com; Apaydin, Aysen [Ankara University, Department of Statistics, 06100 Ankara (Turkey)], E-mail: apaydin@science.ankara.edu.tr

    2009-11-30

    The classical least squares (LS) method is widely used in regression analysis because computing its estimate is easy and traditional. However, LS estimators are very sensitive to outliers and to other deviations from basic assumptions of normal theory [Huynh H. A comparison of four approaches to robust regression. Psychol Bull 1982;92:505-12; Stephenson D. 2000. Available from: (http://folk.uib.no/ngbnk/kurs/notes/node38.html); Xu R, Li C. Multidimensional least-squares fitting with a fuzzy model. Fuzzy Sets and Systems 2001;119:215-23.]. If there exists outliers in the data set, robust methods are preferred to estimate parameters values. We proposed a fuzzy robust regression method by using fuzzy numbers when x is crisp and Y is a triangular fuzzy number and in case of outliers in the data set, a weight matrix was defined by the membership function of the residuals. In the fuzzy robust regression, fuzzy sets and fuzzy regression analysis was used in ranking of residuals and in estimation of regression parameters, respectively [Sanli K, Apaydin A. Fuzzy robust regression analysis based on the ranking of fuzzy sets. Inernat. J. Uncertainty Fuzziness and Knowledge-Based Syst 2008;16:663-81.]. In this study, standard deviation estimations are obtained for the parameters by the defined weight matrix. Moreover, we propose another point of view in hypotheses testing for parameters.

  2. Enhancing network robustness for malicious attacks

    CERN Document Server

    Zeng, An

    2012-01-01

    In a recent work [Proc. Natl. Acad. Sci. USA 108, 3838 (2011)], the authors proposed a simple measure for network robustness under malicious attacks on nodes. With a greedy algorithm, they found the optimal structure with respect to this quantity is an onion structure in which high-degree nodes form a core surrounded by rings of nodes with decreasing degree. However, in real networks the failure can also occur in links such as dysfunctional power cables and blocked airlines. Accordingly, complementary to the node-robustness measurement ($R_{n}$), we propose a link-robustness index ($R_{l}$). We show that solely enhancing $R_{n}$ cannot guarantee the improvement of $R_{l}$. Moreover, the structure of $R_{l}$-optimized network is found to be entirely different from that of onion network. In order to design robust networks resistant to more realistic attack condition, we propose a hybrid greedy algorithm which takes both the $R_{n}$ and $R_{l}$ into account. We validate the robustness of our generated networks a...

  3. Non-Hermitian bidirectional robust transport

    Science.gov (United States)

    Longhi, Stefano

    2017-01-01

    Transport of quantum or classical waves in open systems is known to be strongly affected by non-Hermitian terms that arise from an effective description of system-environment interaction. A simple and paradigmatic example of non-Hermitian transport, originally introduced by Hatano and Nelson two decades ago [N. Hatano and D. R. Nelson, Phys. Rev. Lett. 77, 570 (1996), 10.1103/PhysRevLett.77.570], is the hopping dynamics of a quantum particle on a one-dimensional tight-binding lattice in the presence of an imaginary vectorial potential. The imaginary gauge field can prevent Anderson localization via non-Hermitian delocalization, opening up a mobility region and realizing robust transport immune to disorder and backscattering. Like for robust transport of topologically protected edge states in quantum Hall and topological insulator systems, non-Hermitian robust transport in the Hatano-Nelson model is unidirectional. However, there is not any physical impediment to observe robust bidirectional non-Hermitian transport. Here it is shown that in a quasi-one-dimensional zigzag lattice, with non-Hermitian (imaginary) hopping amplitudes and a synthetic gauge field, robust transport immune to backscattering can occur bidirectionally along the lattice.

  4. Robust Signal Processing in Living Cells

    Science.gov (United States)

    Steuer, Ralf; Waldherr, Steffen; Sourjik, Victor; Kollmann, Markus

    2011-01-01

    Cellular signaling networks have evolved an astonishing ability to function reliably and with high fidelity in uncertain environments. A crucial prerequisite for the high precision exhibited by many signaling circuits is their ability to keep the concentrations of active signaling compounds within tightly defined bounds, despite strong stochastic fluctuations in copy numbers and other detrimental influences. Based on a simple mathematical formalism, we identify topological organizing principles that facilitate such robust control of intracellular concentrations in the face of multifarious perturbations. Our framework allows us to judge whether a multiple-input-multiple-output reaction network is robust against large perturbations of network parameters and enables the predictive design of perfectly robust synthetic network architectures. Utilizing the Escherichia coli chemotaxis pathway as a hallmark example, we provide experimental evidence that our framework indeed allows us to unravel the topological organization of robust signaling. We demonstrate that the specific organization of the pathway allows the system to maintain global concentration robustness of the diffusible response regulator CheY with respect to several dominant perturbations. Our framework provides a counterpoint to the hypothesis that cellular function relies on an extensive machinery to fine-tune or control intracellular parameters. Rather, we suggest that for a large class of perturbations, there exists an appropriate topology that renders the network output invariant to the respective perturbations. PMID:22215991

  5. Robustness analysis of stochastic biochemical systems.

    Science.gov (United States)

    Ceska, Milan; Safránek, David; Dražan, Sven; Brim, Luboš

    2014-01-01

    We propose a new framework for rigorous robustness analysis of stochastic biochemical systems that is based on probabilistic model checking techniques. We adapt the general definition of robustness introduced by Kitano to the class of stochastic systems modelled as continuous time Markov Chains in order to extensively analyse and compare robustness of biological models with uncertain parameters. The framework utilises novel computational methods that enable to effectively evaluate the robustness of models with respect to quantitative temporal properties and parameters such as reaction rate constants and initial conditions. We have applied the framework to gene regulation as an example of a central biological mechanism where intrinsic and extrinsic stochasticity plays crucial role due to low numbers of DNA and RNA molecules. Using our methods we have obtained a comprehensive and precise analysis of stochastic dynamics under parameter uncertainty. Furthermore, we apply our framework to compare several variants of two-component signalling networks from the perspective of robustness with respect to intrinsic noise caused by low populations of signalling components. We have successfully extended previous studies performed on deterministic models (ODE) and showed that stochasticity may significantly affect obtained predictions. Our case studies demonstrate that the framework can provide deeper insight into the role of key parameters in maintaining the system functionality and thus it significantly contributes to formal methods in computational systems biology.

  6. Robust Crossfeed Design for Hovering Rotorcraft

    Science.gov (United States)

    Catapang, David R.

    1993-01-01

    Control law design for rotorcraft fly-by-wire systems normally attempts to decouple angular responses using fixed-gain crossfeeds. This approach can lead to poor decoupling over the frequency range of pilot inputs and increase the load on the feedback loops. In order to improve the decoupling performance, dynamic crossfeeds may be adopted. Moreover, because of the large changes that occur in rotorcraft dynamics due to small changes about the nominal design condition, especially for near-hovering flight, the crossfeed design must be 'robust'. A new low-order matching method is presented here to design robust crossfeed compensators for multi-input, multi-output (MIMO) systems. The technique identifies degrees-of-freedom that can be decoupled using crossfeeds, given an anticipated set of parameter variations for the range of flight conditions of concern. Cross-coupling is then reduced for degrees-of-freedom that can use crossfeed compensation by minimizing off-axis response magnitude average and variance. Results are presented for the analysis of pitch, roll, yaw and heave coupling of the UH-60 Black Hawk helicopter in near-hovering flight. Robust crossfeeds are designed that show significant improvement in decoupling performance and robustness over nominal, single design point, compensators. The design method and results are presented in an easily used graphical format that lends significant physical insight to the design procedure. This plant pre-compensation technique is an appropriate preliminary step to the design of robust feedback control laws for rotorcraft.

  7. Information theory perspective on network robustness

    Energy Technology Data Exchange (ETDEWEB)

    Schieber, Tiago A. [Departmento de Engenharia de Produção, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Industrial and Systems Engineering, University of Florida, Gainesville, FL (United States); Carpi, Laura [Departament de Física i Enginyeria Nuclear, Universitat Politècnica de Catalunya, Colom 11, Terrassa, 08222, Barcelona (Spain); Frery, Alejandro C. [Laboratório de Computação Científica e Análise Numérica (LaCCAN), Universidade Federal de Alagoas, Maceió, Alagoas (Brazil); Rosso, Osvaldo A. [Instituto de Física, Universidade Federal de Alagoas, Maceió, Alagoas (Brazil); Instituto Tecnológico de Buenos Aires (ITBA), Ciudad Autónoma de Buenos Aires (Argentina); Pardalos, Panos M. [Industrial and Systems Engineering, University of Florida, Gainesville, FL (United States); Ravetti, Martín G., E-mail: martin.ravetti@dep.ufmg.br [Departmento de Engenharia de Produção, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Departament de Física Fonamental, Universitat de Barcelona, Barcelona (Spain)

    2016-01-28

    A crucial challenge in network theory is the study of the robustness of a network when facing a sequence of failures. In this work, we propose a dynamical definition of network robustness based on Information Theory, that considers measurements of the structural changes caused by failures of the network's components. Failures are defined here as a temporal process defined in a sequence. Robustness is then evaluated by measuring dissimilarities between topologies after each time step of the sequence, providing a dynamical information about the topological damage. We thoroughly analyze the efficiency of the method in capturing small perturbations by considering different probability distributions on networks. In particular, we find that distributions based on distances are more consistent in capturing network structural deviations, as better reflect the consequences of the failures. Theoretical examples and real networks are used to study the performance of this methodology. - Highlights: • A novel methodology to measure the robustness of a network to component failure or targeted attacks is proposed. • The use of the network's distance PDF allows a precise analysis. • The method provides a dynamic robustness profile showing the response of the topology to each failure event. • The measure is capable to detect network's critical elements.

  8. Robust Face Image Matching under Illumination Variations

    Directory of Open Access Journals (Sweden)

    Yang Chyuan-Huei Thomas

    2004-01-01

    Full Text Available Face image matching is an essential step for face recognition and face verification. It is difficult to achieve robust face matching under various image acquisition conditions. In this paper, a novel face image matching algorithm robust against illumination variations is proposed. The proposed image matching algorithm is motivated by the characteristics of high image gradient along the face contours. We define a new consistency measure as the inner product between two normalized gradient vectors at the corresponding locations in two images. The normalized gradient is obtained by dividing the computed gradient vector by the corresponding locally maximal gradient magnitude. Then we compute the average consistency measures for all pairs of the corresponding face contour pixels to be the robust matching measure between two face images. To alleviate the problem due to shadow and intensity saturation, we introduce an intensity weighting function for each individual consistency measure to form a weighted average of the consistency measure. This robust consistency measure is further extended to integrate multiple face images of the same person captured under different illumination conditions, thus making our robust face matching algorithm. Experimental results of applying the proposed face image matching algorithm on some well-known face datasets are given in comparison with some existing face recognition methods. The results show that the proposed algorithm consistently outperforms other methods and achieves higher than 93% recognition rate with three reference images for different datasets under different lighting conditions.

  9. Functional links and robustness in food webs.

    Science.gov (United States)

    Allesina, Stefano; Bodini, Antonio; Pascual, Mercedes

    2009-06-27

    The robustness of ecosystems to species losses is a central question in ecology, given the current pace of extinctions and the many species threatened by human impacts, including habitat destruction and climate change. Robustness from the perspective of secondary extinctions has been addressed in the context of food webs to consider the complex network of species interactions that underlie responses to perturbations. In-silico removal experiments have examined the structural properties of food webs that enhance or hamper the robustness of ecosystems to species losses, with a focus on the role of hubs, the most connected species. Here we take a different approach and focus on the role of the connections themselves. We show that trophic links can be divided into functional and redundant based on their contribution to robustness. The analysis of empirical webs shows that hubs are not necessarily the most important species as they may hold many redundant links. Furthermore, the fraction of functional connections is high and constant across systems regardless of size and interconnectedness. The main consequence of this scaling pattern is that ecosystem robustness can be considerably reduced by species extinctions even when these do not result in any secondary extinctions. This introduces the possibility of tipping points in the collapse of ecosystems.

  10. Robust Algorithm Development for Application of Pinch Analysis on HEN

    Directory of Open Access Journals (Sweden)

    Ritesh Sojitra

    2016-10-01

    Full Text Available Since its genesis, Pinch Analysis is continuously evolving and its application is widening, reaching new horizons. The original concept of pinch approach was quite clear and, because of flexibility of this approach, innumerable applications have been developed in the industry. Consequently, a designer gets thoroughly muddled among these flexibilities. Hence, there was a need for a rigorous and robust model which could guide the optimisation engineer on deciding the applicability of the pinch approach and direct sequential step of procedure in predefined workflow, so that the precision of approach is ensured. Exploring the various options of a novice hands-on algorithm development that can be coded and interfaced with GUI and keeping in mind the difficulties faced by designers, an effort was made to formulate a new algorithm for the optimisation activity. As such, the work aims at easing out application hurdles and providing hands-on information to the Developer for use during preparation of new application tools. This paper presents a new algorithm, the application which ensures the Developer does not violate basic pinch rules. To achieve this, intermittent check gates are provided in the algorithm, which eliminate violation of predefined basic pinch rules, design philosophy, and Engineering Standards and ensure that constraints are adequately considered. On the other side, its sequential instruction to develop the pinch analysis and reiteration promises Maximum Energy Recovery (MER.

  11. Robust estimation procedure in panel data model

    Energy Technology Data Exchange (ETDEWEB)

    Shariff, Nurul Sima Mohamad [Faculty of Science of Technology, Universiti Sains Islam Malaysia (USIM), 71800, Nilai, Negeri Sembilan (Malaysia); Hamzah, Nor Aishah [Institute of Mathematical Sciences, Universiti Malaya, 50630, Kuala Lumpur (Malaysia)

    2014-06-19

    The panel data modeling has received a great attention in econometric research recently. This is due to the availability of data sources and the interest to study cross sections of individuals observed over time. However, the problems may arise in modeling the panel in the presence of cross sectional dependence and outliers. Even though there are few methods that take into consideration the presence of cross sectional dependence in the panel, the methods may provide inconsistent parameter estimates and inferences when outliers occur in the panel. As such, an alternative method that is robust to outliers and cross sectional dependence is introduced in this paper. The properties and construction of the confidence interval for the parameter estimates are also considered in this paper. The robustness of the procedure is investigated and comparisons are made to the existing method via simulation studies. Our results have shown that robust approach is able to produce an accurate and reliable parameter estimates under the condition considered.

  12. Occupant behaviour and robustness of building design

    DEFF Research Database (Denmark)

    Buso, Tiziana; Fabi, Valentina; Andersen, Rune Korsholm;

    2015-01-01

    with alternating occupant behaviour patterns. The aim of this work was to investigate how alternating occupant behaviour patterns impact the performance of different envelope design solutions in terms of building robustness. Probabilistic models of occupants' window opening and use of shading were implemented...... in a dynamic building energy simulation tool (IDA ICE). The analysis was carried out by simulating 15 building envelope designs in different thermal zones of an Office Reference Building in 3 climates: Stockholm, Frankfurt and Athens.In general, robustness towards changes in occupants' behaviour increased...... with increasing thermal mass and with decreasing transparent area of the envelope. The importance of the robustness' evaluation is highlighted in this paper, in order to obtain optimized buildings' designs for more accurate and realistic energy predictions....

  13. Handling Occlusions for Robust Augmented Reality Systems

    Directory of Open Access Journals (Sweden)

    Madjid Maidi

    2010-01-01

    Full Text Available In Augmented Reality applications, the human perception is enhanced with computer-generated graphics. These graphics must be exactly registered to real objects in the scene and this requires an effective Augmented Reality system to track the user's viewpoint. In this paper, a robust tracking algorithm based on coded fiducials is presented. Square targets are identified and pose parameters are computed using a hybrid approach based on a direct method combined with the Kalman filter. An important factor for providing a robust Augmented Reality system is the correct handling of targets occlusions by real scene elements. To overcome tracking failure due to occlusions, we extend our method using an optical flow approach to track visible points and maintain virtual graphics overlaying when targets are not identified. Our proposed real-time algorithm is tested with different camera viewpoints under various image conditions and shows to be accurate and robust.

  14. Handling Occlusions for Robust Augmented Reality Systems

    Directory of Open Access Journals (Sweden)

    Maidi Madjid

    2010-01-01

    Full Text Available Abstract In Augmented Reality applications, the human perception is enhanced with computer-generated graphics. These graphics must be exactly registered to real objects in the scene and this requires an effective Augmented Reality system to track the user's viewpoint. In this paper, a robust tracking algorithm based on coded fiducials is presented. Square targets are identified and pose parameters are computed using a hybrid approach based on a direct method combined with the Kalman filter. An important factor for providing a robust Augmented Reality system is the correct handling of targets occlusions by real scene elements. To overcome tracking failure due to occlusions, we extend our method using an optical flow approach to track visible points and maintain virtual graphics overlaying when targets are not identified. Our proposed real-time algorithm is tested with different camera viewpoints under various image conditions and shows to be accurate and robust.

  15. GA based robust blind digital watermarking

    CERN Document Server

    Álvarez, Víctor; Frau, María-Dolores; Gudiel, Félix; Güemes, María-Belén; Martín, Elena; Osuna, Amparo

    2012-01-01

    A genetic algorithm based robust blind digital watermarking scheme is presented. Starting from a binary image (the original watermark), a genetic algorithm is performed searching for a permutation of this image which is as uncorrelated as possible to the original watermark. The output of the GA is used as our final watermark, so that both security and robustness in the watermarking process is improved. Now, the original cover image is partitioned into non-overlapped square blocks (depending on the size of the watermark image). Then a (possibly extended) Hadamard transform is applied to these blocks, so that one bit information from the watermark image is embedded in each block by modifying the relationship of two coefficients in the transformed matrices. The watermarked image is finally obtained by simply performing the inverse (extended) Hadamard transform on the modified matrices. The experimental results show that our scheme keeps invisibility, security and robustness more likely than other proposals in th...

  16. Robust audio hashing for audio authentication watermarking

    Science.gov (United States)

    Zmudzinski, Sascha; Steinebach, Martin

    2008-02-01

    Current systems and protocols based on cryptographic methods for integrity and authenticity verification of media data do not distinguish between legitimate signal transformation and malicious tampering that manipulates the content. Furthermore, they usually provide no localization or assessment of the relevance of such manipulations with respect to human perception or semantics. We present an algorithm for a robust message authentication code in the context of content fragile authentication watermarking to verify the integrity of audio recodings by means of robust audio fingerprinting. Experimental results show that the proposed algorithm provides both a high level of distinction between perceptually different audio data and a high robustness against signal transformations that do not change the perceived information. Furthermore, it is well suited for the integration in a content-based authentication watermarking system.

  17. Robust Inference of Risks of Large Portfolios.

    Science.gov (United States)

    Fan, Jianqing; Han, Fang; Liu, Han; Vickers, Byron

    2016-10-01

    We propose a bootstrap-based robust high-confidence level upper bound (Robust H-CLUB) for assessing the risks of large portfolios. The proposed approach exploits rank-based and quantile-based estimators, and can be viewed as a robust extension of the H-CLUB procedure (Fan et al., 2015). Such an extension allows us to handle possibly misspecified models and heavy-tailed data, which are stylized features in financial returns. Under mixing conditions, we analyze the proposed approach and demonstrate its advantage over H-CLUB. We further provide thorough numerical results to back up the developed theory, and also apply the proposed method to analyze a stock market dataset.

  18. Robust fuzzy logic stabilization with disturbance elimination.

    Science.gov (United States)

    Danapalasingam, Kumeresan A

    2014-01-01

    A robust fuzzy logic controller is proposed for stabilization and disturbance rejection in nonlinear control systems of a particular type. The dynamic feedback controller is designed as a combination of a control law that compensates for nonlinear terms in a control system and a dynamic fuzzy logic controller that addresses unknown model uncertainties and an unmeasured disturbance. Since it is challenging to derive a highly accurate mathematical model, the proposed controller requires only nominal functions of a control system. In this paper, a mathematical derivation is carried out to prove that the controller is able to achieve asymptotic stability by processing state measurements. Robustness here refers to the ability of the controller to asymptotically steer the state vector towards the origin in the presence of model uncertainties and a disturbance input. Simulation results of the robust fuzzy logic controller application in a magnetic levitation system demonstrate the feasibility of the control design.

  19. Robustness of Inflation to Inhomogeneous Initial Conditions

    CERN Document Server

    Clough, Katy; DiNunno, Brandon S; Fischler, Willy; Flauger, Raphael; Paban, Sonia

    2016-01-01

    We consider the effects of inhomogeneous initial conditions in both the scalar field profile and the extrinsic curvature on different inflationary models. In particular, we compare the robustness of small field inflation to that of large field inflation, using numerical simulations with Einstein gravity in 3+1 dimensions. We find that small field inflation can fail in the presence of subdominant gradient energies, suggesting that it is much less robust to inhomogeneities than large field inflation, which withstands dominant gradient energies. However, we also show that small field inflation can be successful even if some regions of spacetime start out in the region of the potential that does not support inflation. In the large field case, we confirm the results of [1-3] that inflation is robust if the inflaton occupies the inflationary part of the potential. Furthermore, we show that increasing initial scalar gradients will not form sufficiently massive inflation-ending black holes if the initial hypersurface...

  20. Robust H2 estimation and control

    Institute of Scientific and Technical Information of China (English)

    Lihua XIE; Yeng Chai SOH; Chunling DU; Yun ZOU

    2004-01-01

    This paper is concerned with the H2 estimation and control problems for uncertain discretetime systems with norm-bounded parameter uncertainty. We first present an analysis result on H2 norm bound for a stable uncertain system in terms of linearmatrix inequalities (LMIs). A solution to the robust H2 estimation problem is then derived in terms of two LMIs. As compared tothe existing results, our result on robust H2 estimation is more general. In addition, explicit search of appropriate scaling parametersis not needed as the optimization is convex in the scaling parameters. The LMI approach is also extended to solve the robust H2control problem which has been difficult for the traditional Riccati equation approach since no separation principle has been knownfor uncertain systems. The design approach is demonstrated through a simple example.

  1. Synthesis Methods for Robust Passification and Control

    Science.gov (United States)

    Kelkar, Atul G.; Joshi, Suresh M. (Technical Monitor)

    2000-01-01

    The research effort under this cooperative agreement has been essentially the continuation of the work from previous grants. The ongoing work has primarily focused on developing passivity-based control techniques for Linear Time-Invariant (LTI) systems. During this period, there has been a significant progress made in the area of passivity-based control of LTI systems and some preliminary results have also been obtained for nonlinear systems, as well. The prior work has addressed optimal control design for inherently passive as well as non- passive linear systems. For exploiting the robustness characteristics of passivity-based controllers the passification methodology was developed for LTI systems that are not inherently passive. Various methods of passification were first proposed in and further developed. The robustness of passification was addressed for multi-input multi-output (MIMO) systems for certain classes of uncertainties using frequency-domain methods. For MIMO systems, a state-space approach using Linear Matrix Inequality (LMI)-based formulation was presented, for passification of non-passive LTI systems. An LMI-based robust passification technique was presented for systems with redundant actuators and sensors. The redundancy in actuators and sensors was used effectively for robust passification using the LMI formulation. The passification was designed to be robust to an interval-type uncertainties in system parameters. The passification techniques were used to design a robust controller for Benchmark Active Control Technology wing under parametric uncertainties. The results on passive nonlinear systems, however, are very limited to date. Our recent work in this area was presented, wherein some stability results were obtained for passive nonlinear systems that are affine in control.

  2. Semiempirical robust algorithm for investment portfolio formation

    Directory of Open Access Journals (Sweden)

    Natalja Kaskevič

    2013-03-01

    Full Text Available When analyzing stock market data, it is common to encounter observations that differ from the overall pattern. It is known as the problem of robustness. Presence of outlying observations in different data sets may strongly influence the result of classical (mean and standard deviation based analysis methods or models based on this data. The problem of outliers can be handled by using robust estimators, therefore making aberrations less influential or ignoring them completely. An example of applying such procedures for outlier elimination in stock trading system optimization process is presented.

  3. Robust MPEG Watermarking in DWT Four Bands

    Directory of Open Access Journals (Sweden)

    E. Elbaşı

    2012-04-01

    Full Text Available In this paper, we generalize an idea in a recent paper that embeds a binary pattern in the form of a binary image in the wavelet domain for images. Our generalization includes all four bands (LL, LH, HL and HH in the DWT for MPEG video sequences. We tested the proposed algorithm against twelve attacks. Embedding the watermark in lower frequencies is robust to one group of attacks, and embedding the watermark in higher frequencies is robust to another group of attacks.

  4. Robust control synthesis for uncertain dynamical systems

    Science.gov (United States)

    Byun, Kuk-Whan; Wie, Bong; Sunkel, John

    1989-01-01

    This paper presents robust control synthesis techniques for uncertain dynamical systems subject to structured parameter perturbation. Both QFT (quantitative feedback theory) and H-infinity control synthesis techniques are investigated. Although most H-infinity-related control techniques are not concerned with the structured parameter perturbation, a new way of incorporating the parameter uncertainty in the robust H-infinity control design is presented. A generic model of uncertain dynamical systems is used to illustrate the design methodologies investigated in this paper. It is shown that, for a certain noncolocated structural control problem, use of both techniques results in nonminimum phase compensation.

  5. Robust cluster analysis and variable selection

    CERN Document Server

    Ritter, Gunter

    2014-01-01

    Clustering remains a vibrant area of research in statistics. Although there are many books on this topic, there are relatively few that are well founded in the theoretical aspects. In Robust Cluster Analysis and Variable Selection, Gunter Ritter presents an overview of the theory and applications of probabilistic clustering and variable selection, synthesizing the key research results of the last 50 years. The author focuses on the robust clustering methods he found to be the most useful on simulated data and real-time applications. The book provides clear guidance for the varying needs of bot

  6. Robust adaptive beamforming for MIMO monopulse radar

    Science.gov (United States)

    Rowe, William; Ström, Marie; Li, Jian; Stoica, Petre

    2013-05-01

    Researchers have recently proposed a widely separated multiple-input multiple-output (MIMO) radar using monopulse angle estimation techniques for target tracking. The widely separated antennas provide improved tracking performance by mitigating complex target radar cross-section fades and angle scintillation. An adaptive array is necessary in this paradigm because the direct path from any transmitter could act as a jammer at a receiver. When the target-free covariance matrix is not available, it is critical to include robustness into the adaptive beamformer weights. This work explores methods of robust adaptive monopulse beamforming techniques for MIMO tracking radar.

  7. Smith Predictor Based Robust Rapid Tracking Controller

    Institute of Scientific and Technical Information of China (English)

    LIU Hongbin; HU Dejin

    2006-01-01

    Precise model is hard to get in real application, a Smith predictor based robust rapid tracking controller for inaccurate model is proposed. Zero phase error feedforward controller which increases system closed-loop dynamics and disturbance observer based Smith feedback control which diminishes model hysteresis and improves stability are integrated. This method is applied in the noncircular machining with piezoelectric ceramic driver. The simulation and experiment show that the performance robustness and stability are well balanced in bandwidth about 200 Hz. The controller can decrease system hysteresis and get good tracking performance for predefined square-wave input signal.

  8. Security analysis of robust perceptual hashing

    Science.gov (United States)

    Koval, Oleksiy; Voloshynovskiy, Sviatoslav; Beekhof, Fokko; Pun, Thierry

    2008-02-01

    In this paper we considered the problem of security analysis of robust perceptual hashing in authentication application. The main goal of our analysis was to estimate the amount of trial efforts of the attacker, who is acting within the Kerckhoffs security principle, to reveal a secret key. For this purpose, we proposed to use Shannon equivocation that provides an estimate of complexity of the key search performed based on all available prior information and presented its application to security evaluation of particular robust perceptual hashing algorithms.

  9. Robust hyperchaotic synchronization via analog transmission line

    Science.gov (United States)

    Sadoudi, S.; Tanougast, C.

    2016-02-01

    In this paper, a novel experimental chaotic synchronization technique via analog transmission is discussed. We demonstrate through Field-Programmable Gate Array (FPGA) implementation design the robust synchronization of two embedded hyperchaotic Lorenz generators interconnected with an analog transmission line. The basic idea of this work consists in combining a numerical generation of chaos and transmitting it with an analog signal. The numerical chaos allows to overcome the callback parameter mismatch problem and the analog transmission offers robust data security. As application, this technique can be applied to all families of chaotic systems including time-delayed chaotic systems.

  10. Recent Advances in Robust Speech Recognition Technology

    CERN Document Server

    Ramírez, Javier

    2011-01-01

    This E-book is a collection of articles that describe advances in speech recognition technology. Robustness in speech recognition refers to the need to maintain high speech recognition accuracy even when the quality of the input speech is degraded, or when the acoustical, articulate, or phonetic characteristics of speech in the training and testing environments differ. Obstacles to robust recognition include acoustical degradations produced by additive noise, the effects of linear filtering, nonlinearities in transduction or transmission, as well as impulsive interfering sources, and diminishe

  11. Introduction to Robust Estimation and Hypothesis Testing

    CERN Document Server

    Wilcox, Rand R

    2012-01-01

    This revised book provides a thorough explanation of the foundation of robust methods, incorporating the latest updates on R and S-Plus, robust ANOVA (Analysis of Variance) and regression. It guides advanced students and other professionals through the basic strategies used for developing practical solutions to problems, and provides a brief background on the foundations of modern methods, placing the new methods in historical context. Author Rand Wilcox includes chapter exercises and many real-world examples that illustrate how various methods perform in different situations.Introduction to R

  12. ROBUST STABILITY ANALYSIS FOR RAILWAY VEHICLE SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    Wang Yong; Zeng Jing; Cao Dengqing

    2003-01-01

    The lateral stability for railway vehicle dynamic system with uncertain parameters and nonlinear uncertain force vector is studied by using the Lyapunov stability theory. A robust stability condition for the considered system is derived, and the obtained stability bounds are not necessarily symmetric with respect to the origin in the parameter space. The lateral stability analysis for a railway bogie model is analyzed by using the proposed approach. The symmetric and asymmetric results are both given and the influence of the adjustable parameter ( on the stability bounds is also discussed. With the help of the proposed method, the robust stability analysis can provide a reference for the design of the railway vehicle systems.

  13. Robust Reachability of Boolean Control Networks.

    Science.gov (United States)

    Li, Fangfei; Tang, Yang

    2016-04-20

    Boolean networks serve a powerful tool in analysis of genetic regulatory networks since it emphasizes the fundamental principles and establishes a nature framework for capturing the dynamics of regulation of cellular states. In this paper, the robust reachability of Boolean control networks is investigated by means of semi-tensor product. Necessary and sufficient conditions for the robust reachability of Boolean control networks are provided, in which control inputs relying on disturbances or not are considered, respectively. Besides, the corresponding control algorithms are developed for these two cases. A reduced model of the lac operon in the Escherichia coli is presented to show the effectiveness of the presented results.

  14. Robust speaker recognition in noisy environments

    CERN Document Server

    Rao, K Sreenivasa

    2014-01-01

    This book discusses speaker recognition methods to deal with realistic variable noisy environments. The text covers authentication systems for; robust noisy background environments, functions in real time and incorporated in mobile devices. The book focuses on different approaches to enhance the accuracy of speaker recognition in presence of varying background environments. The authors examine: (a) Feature compensation using multiple background models, (b) Feature mapping using data-driven stochastic models, (c) Design of super vector- based GMM-SVM framework for robust speaker recognition, (d) Total variability modeling (i-vectors) in a discriminative framework and (e) Boosting method to fuse evidences from multiple SVM models.

  15. Fuzzy Design Method of Product Quality Robustness

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In order to express information on the quality grade of product, designed, the target value of product quality design was described with a fuzzy number in this paper. The rule of robust design with a fuzzy target was analyzed with fuzzy probability theory,then the principle and modeling method of fuzzy robust design for a high quality product were put forward. With this new method used, the high-quality ratio of the product de-signed could be increased, and the ability to resist the influence of various disturbing fac-tors ang noise factors could be enhanced.

  16. Grassmann Averages for Scalable Robust PCA

    DEFF Research Database (Denmark)

    Hauberg, Søren; Feragen, Aasa; Black, Michael J.

    2014-01-01

    arbitrarily corrupt the results. Unfortunately, state-of-the-art approaches for robust PCA do not scale beyond small-to-medium sized datasets. To address this, we introduce the Grassmann Average (GA), which expresses dimensionality reduction as an average of the subspaces spanned by the data. Because averages...... to vectors (subspaces) or elements of vectors; we focus on the latter and use a trimmed average. The resulting Trimmed Grassmann Average (TGA) is particularly appropriate for computer vision because it is robust to pixel outliers. The algorithm has low computational complexity and minimal memory requirements...

  17. Early Childhood Program for the Handicapped in France.

    Science.gov (United States)

    Zucman, Elisabeth

    1985-01-01

    Early intervention in France begins with compulsory screening of all infants at birth, nine months, and at two years. Problems remain, especially in the availability of adequate support and of services for the handicapped child. Interdisciplinary teams operate from "early medico-social activity centers" to provide a variety of…

  18. Robust stabilization, robust performance, and disturbance attenuation for uncertain linear systems

    Science.gov (United States)

    Wang, Yeih J.; Shieh, Leang S.; Sunkel, John W.

    1992-01-01

    This paper presents a linear quadratic regulator approach to the robust stabilization, robust performance, and disturbance attenuation of uncertain linear systems. The state-feedback designed systems provide both the robust stability with optimal performance and the disturbance attenuation with H-infinity-norm bounds. The proposed approach can be applied to matched and/or mismatched uncertain linear systems. For a matched uncertain linear system, it is shown that the disturbance attenuation robust-stabilizing controllers with or without optimal performance always exist and can be easily determined without searching; whereas, for a mismatched uncertain linear system, the introduced tuning parameters greatly enhance the flexibility of finding the disturbance-attenuation robust-stabilizing controllers.

  19. Early clerkships

    NARCIS (Netherlands)

    Kamalski, Digna M. A.; Ter Braak, Edith W. M. T.; Ten Cate, Olle Th. J.; Borleffs, Jan C. C.

    2007-01-01

    Background: Early clinical experience is being introduced in innovative, vertically integrated undergraduate medical curricula. While in many cases, this early clinical experience is limited to the presence of patients during lectures, in Utrecht students gain 'hands on' experience of daily clinical

  20. Direct selection on genetic robustness revealed in the yeast transcriptome.

    Directory of Open Access Journals (Sweden)

    Stephen R Proulx

    Full Text Available BACKGROUND: Evolutionary theory predicts that organisms should evolve the ability to produce high fitness phenotypes in the face of environmental disturbances (environmental robustness or genetic mutations (genetic robustness. While several studies have uncovered mechanisms that lead to both environmental and genetic robustness, we have yet to understand why some components of the genome are more robust than others. According to evolutionary theory, environmental and genetic robustness will have different responses to selective forces. Selection on environmental robustness for a trait is expected to be strong and related to the fitness costs of altering that trait. In contrast to environmental robustness, selection on genetic robustness for a trait is expected to be largely independent of the fitness cost of altering the trait and instead should correlate with the standing genetic variation for the trait that can potentially be buffered. Several mechanisms that provide both environmental and genetic robustness have been described, and this correlation could be explained by direct selection on both forms of robustness (direct selection hypothesis, or through selection on environmental robustness and a correlated response in genetic robustness (congruence hypothesis. METHODOLOGY/PRINCIPAL FINDINGS: Using both published and novel data on gene expression in the yeast Saccharomyces cerevisiae, we find that genetic robustness is correlated with environmental robustness across the yeast genome as predicted by the congruence hypothesis. However, we also show that environmental robustness, but not genetic robustness, is related to per-gene fitness effects. In contrast, genetic robustness is significantly correlated with network position, suggesting that genetic robustness has been under direct selection. CONCLUSIONS/SIGNIFICANCE: We observed a significant correlation between our measures of genetic and environmental robustness, in agreement with the

  1. The Leap of a Provincial SME into the Global Market Using E-commerce: The Success of Adequate Planning

    Science.gov (United States)

    Sainz de Abajo, Beatriz; García Salcines, Enrique; Burón Fernández, F. Javier; López Coronado, Miguel; de Castro Lozano, Carlos

    The leap into the global market is not easy when it involves a provincial family business. This article demonstrates how adequate planning is fundamental in a small and medium-sized enterprise (SME) with the tight budget they have available to them, in order to be able to differentiate themselves in a highly competitive market, taking into accounts the benefits and risks involved. The Information Technology (IT) tools put in place will give the necessary support and allow for the possibility of increasing and improving the infrastructure as the company requires. An adequate strategy for the future to increases sales would be e-marketing techniques as well as the current promotions which contribute to diffusing the brand.

  2. Thermodynamic study and modelling of iron-based melts for adequate prediction of modern ladle metallurgy processes

    Science.gov (United States)

    Zaitsev, A. I.; Rodionova, I. G.; Shaposhnikov, N. G.; Zemlyanko, O. A.; Karamisheva, N. A.

    2008-02-01

    The representation of iron-based melts as associated liquids have been developed basing on the detail experimental investigation and analysis of available data on their thermodynamic properties and phase equilibria. It has allowed, for the first time, to interpret adequately the reactivity of the earth metals in the iron-based melts and to predict with high precision the reactions of metal refinement and non-metallic inclusions modifying in modern ladle metallurgy.

  3. The maternal-to-zygotic transition targets actin to promote robustness during morphogenesis.

    Science.gov (United States)

    Zheng, Liuliu; Sepúlveda, Leonardo A; Lua, Rhonald C; Lichtarge, Olivier; Golding, Ido; Sokac, Anna Marie

    2013-11-01

    Robustness is a property built into biological systems to ensure stereotypical outcomes despite fluctuating inputs from gene dosage, biochemical noise, and the environment. During development, robustness safeguards embryos against structural and functional defects. Yet, our understanding of how robustness is achieved in embryos is limited. While much attention has been paid to the role of gene and signaling networks in promoting robust cell fate determination, little has been done to rigorously assay how mechanical processes like morphogenesis are designed to buffer against variable conditions. Here we show that the cell shape changes that drive morphogenesis can be made robust by mechanisms targeting the actin cytoskeleton. We identified two novel members of the Vinculin/α-Catenin Superfamily that work together to promote robustness during Drosophila cellularization, the dramatic tissue-building event that generates the primary epithelium of the embryo. We find that zygotically-expressed Serendipity-α (Sry-α) and maternally-loaded Spitting Image (Spt) share a redundant, actin-regulating activity during cellularization. Spt alone is sufficient for cellularization at an optimal temperature, but both Spt plus Sry-α are required at high temperature and when actin assembly is compromised by genetic perturbation. Our results offer a clear example of how the maternal and zygotic genomes interact to promote the robustness of early developmental events. Specifically, the Spt and Sry-α collaboration is informative when it comes to genes that show both a maternal and zygotic requirement during a given morphogenetic process. For the cellularization of Drosophilids, Sry-α and its expression profile may represent a genetic adaptive trait with the sole purpose of making this extreme event more reliable. Since all morphogenesis depends on cytoskeletal remodeling, both in embryos and adults, we suggest that robustness-promoting mechanisms aimed at actin could be effective at

  4. The maternal-to-zygotic transition targets actin to promote robustness during morphogenesis.

    Directory of Open Access Journals (Sweden)

    Liuliu Zheng

    2013-11-01

    Full Text Available Robustness is a property built into biological systems to ensure stereotypical outcomes despite fluctuating inputs from gene dosage, biochemical noise, and the environment. During development, robustness safeguards embryos against structural and functional defects. Yet, our understanding of how robustness is achieved in embryos is limited. While much attention has been paid to the role of gene and signaling networks in promoting robust cell fate determination, little has been done to rigorously assay how mechanical processes like morphogenesis are designed to buffer against variable conditions. Here we show that the cell shape changes that drive morphogenesis can be made robust by mechanisms targeting the actin cytoskeleton. We identified two novel members of the Vinculin/α-Catenin Superfamily that work together to promote robustness during Drosophila cellularization, the dramatic tissue-building event that generates the primary epithelium of the embryo. We find that zygotically-expressed Serendipity-α (Sry-α and maternally-loaded Spitting Image (Spt share a redundant, actin-regulating activity during cellularization. Spt alone is sufficient for cellularization at an optimal temperature, but both Spt plus Sry-α are required at high temperature and when actin assembly is compromised by genetic perturbation. Our results offer a clear example of how the maternal and zygotic genomes interact to promote the robustness of early developmental events. Specifically, the Spt and Sry-α collaboration is informative when it comes to genes that show both a maternal and zygotic requirement during a given morphogenetic process. For the cellularization of Drosophilids, Sry-α and its expression profile may represent a genetic adaptive trait with the sole purpose of making this extreme event more reliable. Since all morphogenesis depends on cytoskeletal remodeling, both in embryos and adults, we suggest that robustness-promoting mechanisms aimed at actin

  5. Robust glint detection through homography normalization

    DEFF Research Database (Denmark)

    Hansen, Dan Witzner; Roholm, Lars; García Ferreiros, Iván

    2014-01-01

    A novel normalization principle for robust glint detection is presented. The method is based on geometric properties of corneal reflections and allows for simple and effective detection of glints even in the presence of several spurious and identically appearing reflections. The method is tested...

  6. Robust and Adaptive Control With Aerospace Applications

    CERN Document Server

    Lavretsky, Eugene

    2013-01-01

    Robust and Adaptive Control shows the reader how to produce consistent and accurate controllers that operate in the presence of uncertainties and unforeseen events. Driven by aerospace applications the focus of the book is primarily on continuous-dynamical systems.  The text is a three-part treatment, beginning with robust and optimal linear control methods and moving on to a self-contained presentation of the design and analysis of model reference adaptive control (MRAC) for nonlinear uncertain dynamical systems. Recent extensions and modifications to MRAC design are included, as are guidelines for combining robust optimal and MRAC controllers. Features of the text include: ·         case studies that demonstrate the benefits of robust and adaptive control for piloted, autonomous and experimental aerial platforms; ·         detailed background material for each chapter to motivate theoretical developments; ·         realistic examples and simulation data illustrating key features ...

  7. Implementing robust neuromodulation in neuromorphic circuits

    OpenAIRE

    Castaños, Fernando; Franci, Alessio

    2016-01-01

    We introduce a methodology to implement the physiological transition {between distinct neuronal spiking modes} in electronic circuits composed of resistors, capacitors and transistors. The result is a simple neuromorphic device organized by the same geometry {and exhibiting the same input--output properties as} high-dimensional electrophysiological neuron models. {Preliminary} experimental results highlight the robustness of the approach in real-world applications.

  8. Robust inference in sample selection models

    KAUST Repository

    Zhelonkin, Mikhail

    2015-11-20

    The problem of non-random sample selectivity often occurs in practice in many fields. The classical estimators introduced by Heckman are the backbone of the standard statistical analysis of these models. However, these estimators are very sensitive to small deviations from the distributional assumptions which are often not satisfied in practice. We develop a general framework to study the robustness properties of estimators and tests in sample selection models. We derive the influence function and the change-of-variance function of Heckman\\'s two-stage estimator, and we demonstrate the non-robustness of this estimator and its estimated variance to small deviations from the model assumed. We propose a procedure for robustifying the estimator, prove its asymptotic normality and give its asymptotic variance. Both cases with and without an exclusion restriction are covered. This allows us to construct a simple robust alternative to the sample selection bias test. We illustrate the use of our new methodology in an analysis of ambulatory expenditures and we compare the performance of the classical and robust methods in a Monte Carlo simulation study.

  9. Robust stability of interval parameter matrices

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This note is devoted to the problem of robust stability of interval parameter matrices. Based on some basic facts relating the H∞ norm of a transfer function to the Riccati matrix inequality and Hamilton matrix, several test conditions with parameter perturbation bounds are obtained.

  10. Design Intelligent Robust Back stepping Controller

    Directory of Open Access Journals (Sweden)

    Zahra Esmaieli

    2014-01-01

    Full Text Available The increasing demand for multi-degree-of-freedom (DOF continuum robot in presence of highly nonlinear dynamic parameters in a number of industries has motivated a flurry of research in the development of soft computing nonlinear methodology. The robust backstopping controller proposed in this research is used to further demonstrate the appealing features exhibited by the continuum robot. Robust feedback controller is used to position control of continuum robot in presence of uncertainties. Using Lyapunov type stability arguments, a robust backstopping controller is designed to achieve this objective. The controller developed in this research is designed into two steps. Firstly, a robust stabilizing torque is designed for the nominal continuum robot dynamics derived using the constrained Lagrangian formulation based on modified PD backstopping controller. Next, the fuzzy logic methodology applied to it to solution uncertainty problem. The fuzzy model free problem is formulated to estimate the nonlinear formulation of continuum robot. The eventual stability of the controller depends on the torque generating capabilities of the continuum robots.

  11. Robust Geometric Control of a Distillation Column

    DEFF Research Database (Denmark)

    Kymmel, Mogens; Andersen, Henrik Weisberg

    1987-01-01

    A frequency domain method, which makes it possible to adjust multivariable controllers with respect to both nominal performance and robustness, is presented. The basic idea in the approach is that the designer assigns objectives such as steady-state tracking, maximum resonance peaks, bandwidth, m...... is used to examine and improve geometric control of a binary distillation column....

  12. A robust interpretation of duration calculus

    DEFF Research Database (Denmark)

    Franzle, M.; Hansen, Michael Reichhardt

    2005-01-01

    Calculus (DC), our findings are that the robust interpretation of DC is equivalent to a multi-valued interpretation that uses the real numbers as semantic domain and assigns Lipschitz-continuous interpretations to all operators of DC. Furthermore, this continuity permits approximation between discrete...

  13. Finite Algorithms for Robust Linear Regression

    DEFF Research Database (Denmark)

    Madsen, Kaj; Nielsen, Hans Bruun

    1990-01-01

    The Huber M-estimator for robust linear regression is analyzed. Newton type methods for solution of the problem are defined and analyzed, and finite convergence is proved. Numerical experiments with a large number of test problems demonstrate efficiency and indicate that this kind of approach may...

  14. Robust balance shift control with posture optimization

    NARCIS (Netherlands)

    Kavafoglu, Z.; Kavafoglu, Ersan; Egges, J.

    2015-01-01

    In this paper we present a control framework which creates robust and natural balance shifting behaviours during standing. Given high-level features such as the position of the center of mass projection and the foot configurations, a kinematic posture satisfying these features is synthesized using o

  15. A robust adaptive controller for robot manipulators

    NARCIS (Netherlands)

    Berghuis, Harry; Ortega, Romeo; Nijmeijer, Henk

    1992-01-01

    The authors propose a globally convergent adaptive control scheme for robot motion control with the following features: first, the adaptation law processes enhanced robustness with respect to noisy velocity measurements; secondly, the controller does not require the inclusion of high-gain loops that

  16. Robustness of dynamic systems with parameter uncertainties

    CERN Document Server

    Balemi, S; Truöl, W

    1992-01-01

    Robust Control is one of the fastest growing and promising areas of research today. In many practical systems there exist uncertainties which have to be considered in the analysis and design of control systems. In the last decade methods were developed for dealing with dynamic systems with unstructured uncertainties such as HOO_ and £I-optimal control. For systems with parameter uncertainties, the seminal paper of V. L. Kharitonov has triggered a large amount of very promising research. An international workshop dealing with all aspects of robust control was successfully organized by S. P. Bhattacharyya and L. H. Keel in San Antonio, Texas, USA in March 1991. We organized the second international workshop in this area in Ascona, Switzer­ land in April 1992. However, this second workshop was restricted to robust control of dynamic systems with parameter uncertainties with the objective to concentrate on some aspects of robust control. This book contains a collection of papers presented at the International W...

  17. Replication and Robustness in Developmental Research

    Science.gov (United States)

    Duncan, Greg J.; Engel, Mimi; Claessens, Amy; Dowsett, Chantelle J.

    2014-01-01

    Replications and robustness checks are key elements of the scientific method and a staple in many disciplines. However, leading journals in developmental psychology rarely include explicit replications of prior research conducted by different investigators, and few require authors to establish in their articles or online appendices that their key…

  18. Robust classification using mixtures of dependency networks

    DEFF Research Database (Denmark)

    Gámez, José A.; Mateo, Juan L.; Nielsen, Thomas Dyhre

    2008-01-01

    -ups are often obtained at the expense of accuracy. In this paper we try to address this issue through the use of mixtures of dependency networks. To reduce learning time and improve robustness when dealing with data sparse classes, we outline methods for reusing calculations across mixture components. Finally...

  19. Robustness Assessment of Spatial Timber Structures

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning

    2012-01-01

    Robustness of structural systems has obtained a renewed interest due to a much more frequent use of advanced types of structures with limited redundancy and serious consequences in case of failure. In order to minimise the likelihood of such disproportionate structural failures many modern buildi...

  20. The quantitative genetics of phenotypic robustness.

    Directory of Open Access Journals (Sweden)

    Hunter B Fraser

    Full Text Available Phenotypic robustness, or canalization, has been extensively investigated both experimentally and theoretically. However, it remains unknown to what extent robustness varies between individuals, and whether factors buffering environmental variation also buffer genetic variation. Here we introduce a quantitative genetic approach to these issues, and apply this approach to data from three species. In mice, we find suggestive evidence that for hundreds of gene expression traits, robustness is polymorphic and can be genetically mapped to discrete genomic loci. Moreover, we find that the polymorphisms buffering genetic variation are distinct from those buffering environmental variation. In fact, these two classes have quite distinct mechanistic bases: environmental buffers of gene expression are predominantly sex-specific and trans-acting, whereas genetic buffers are not sex-specific and often cis-acting. Data from studies of morphological and life-history traits in plants and yeast support the distinction between polymorphisms buffering genetic and environmental variation, and further suggest that loci buffering different types of environmental variation do overlap with one another. These preliminary results suggest that naturally occurring polymorphisms affecting phenotypic robustness could be abundant, and that these polymorphisms may generally buffer either genetic or environmental variation, but not both.

  1. Robust online face tracking-by-detection

    NARCIS (Netherlands)

    Comaschi, F.; Stuijk, S.; Basten, T.; Corporaal, H.

    2016-01-01

    The problem of online face tracking from unconstrained videos is still unresolved. Challenges range from coping with severe online appearance variations to coping with occlusion. We propose RFTD (Robust Face Tracking-by-Detection), a system which combines tracking and detection into a single framewo

  2. Neuromorphic Configurable Architecture for Robust Motion Estimation

    Directory of Open Access Journals (Sweden)

    Guillermo Botella

    2008-01-01

    Full Text Available The robustness of the human visual system recovering motion estimation in almost any visual situation is enviable, performing enormous calculation tasks continuously, robustly, efficiently, and effortlessly. There is obviously a great deal we can learn from our own visual system. Currently, there are several optical flow algorithms, although none of them deals efficiently with noise, illumination changes, second-order motion, occlusions, and so on. The main contribution of this work is the efficient implementation of a biologically inspired motion algorithm that borrows nature templates as inspiration in the design of architectures and makes use of a specific model of human visual motion perception: Multichannel Gradient Model (McGM. This novel customizable architecture of a neuromorphic robust optical flow can be constructed with FPGA or ASIC device using properties of the cortical motion pathway, constituting a useful framework for building future complex bioinspired systems running in real time with high computational complexity. This work includes the resource usage and performance data, and the comparison with actual systems. This hardware has many application fields like object recognition, navigation, or tracking in difficult environments due to its bioinspired and robustness properties.

  3. Robust Multiparty Computation with Linear Communication Complexity

    DEFF Research Database (Denmark)

    Hirt, Martin; Nielsen, Jesper Buus

    2006-01-01

    We present a robust multiparty computation protocol. The protocol is for the cryptographic model with open channels and a poly-time adversary, and allows n parties to actively securely evaluate any poly-sized circuit with resilience t < n/2. The total communication complexity in bits over the poi...

  4. Robust Utility Maximization Under Convex Portfolio Constraints

    Energy Technology Data Exchange (ETDEWEB)

    Matoussi, Anis, E-mail: anis.matoussi@univ-lemans.fr [Université du Maine, Risk and Insurance institut of Le Mans Laboratoire Manceau de Mathématiques (France); Mezghani, Hanen, E-mail: hanen.mezghani@lamsin.rnu.tn; Mnif, Mohamed, E-mail: mohamed.mnif@enit.rnu.tn [University of Tunis El Manar, Laboratoire de Modélisation Mathématique et Numérique dans les Sciences de l’Ingénieur, ENIT (Tunisia)

    2015-04-15

    We study a robust maximization problem from terminal wealth and consumption under a convex constraints on the portfolio. We state the existence and the uniqueness of the consumption–investment strategy by studying the associated quadratic backward stochastic differential equation. We characterize the optimal control by using the duality method and deriving a dynamic maximum principle.

  5. Nonlinear Robust Control Theory and Applications

    Science.gov (United States)

    1997-01-18

    IEEE Transactions on Automatic Control , pp. 228-238...34Robustness in the presence of mixed parametric uncertainty and unmodelled dynamics," IEEE Transactions on Automatic Control , pp. 25-38, 1991. 8 [10...Letter, 1994. [14] B. Moore, "Principal component analysis of linear systems: Controllability, observ- ability and model reduction," IEEE Transactions on Automatic Control ,

  6. Stabilization of nonlinear systems based on robust control Lyapunov function

    Institute of Scientific and Technical Information of China (English)

    CAI Xiu-shan; HAN Zheng-zhi; LU Gan-yun

    2007-01-01

    This paper deals with the robust stabilization problem for a class of nonlinear systems with structural uncertainty. Based on robust control Lyapunov function, a sufficient and necessary condition for a function to be a robust control Lyapunov function is given. From this condition, simply sufficient condition for the robust stabilization (robust practical stabilization) is deduced. Moreover, if the equilibrium of the closed-loop system is unique, the existence of such a robust control Lyapunov function will also imply robustly globally asymptotical stabilization. Then a continuous state feedback law can be constructed explicitly. The simulation shows the effectiveness of the method.

  7. Early literacy

    DEFF Research Database (Denmark)

    Jensen, Anders Skriver

    2012-01-01

    This paper discusses findings from the Danish contribution to the EASE project, a European research project running from 2008 to 2010 on early literacy in relation to the transition from childcare to school. It explores a holistic, inclusive approach to early literacy that resists a narrow...... and schools. The paper also draws on Gee’s (2001, 2003, 2004, 2008) sociocultural approach to literacy, and Honneth’s (2003, 2006) concept of recognition. Emphasizing participation and recognition as key elements, it claims that stakeholders in early liter- acy must pay attention to how diverse early literacy...... opportunities empower children, especially when these opportunities are employed in a project-based learning environ- ment in which each child is able to contribute to the shared literacy events....

  8. Are the U.S. Navy’s Current Procedures for Responding to Homeland Defense and Security Tasking Adequately Designed?

    Science.gov (United States)

    2009-12-01

    It is estimated that the average citizen residing in an industrialized country uses 10 gallons of water for domestic use per day, source, Feiss ...communication via line of sight (LOS) as well as the use of satellites, making the Nimitz class communication suite robust and redundant. These... line of command to increase readiness and responsiveness.125 1st BCT units consist of: 3rd Battalion 69th Armor Regiment, 2nd Battalion 7th

  9. A Robust Optimization Approach Considering the Robustness of Design Objectives and Constraints

    Institute of Scientific and Technical Information of China (English)

    LIUChun-tao; LINZhi-hang; ZHOUChunojing

    2005-01-01

    The problem of robust design is treated as a multi-objective optimization issue in which the performance mean and variation are optimized and minimized respectively, while maintaining the feasibility of design constraints under uncertainty. To effectively address this issue in robust design, this paper presents a novel robust optimization approach which integrates multi-objective optimization concepts with Taguchi's crossed arrays techniques. In this approach,Pareto-optimal robust design solution sets are obtained with the aid of design of experiment set-ups,which utilize the results of Analysis of Variance to quantify relative dominance and significance of design variables. A beam design problem is used to illustrate the effectiveness of the proposed approach.

  10. Subjects with molecularly defined familial hypercholesterolemia or familial defective apoB-100 are not being adequately treated.

    Directory of Open Access Journals (Sweden)

    Trond P Leren

    Full Text Available OBJECTIVES: To study whether subjects with a molecular genetic diagnosis of familial hypercholesterolemia (FH or familial defective apoB-100 (FDB are being adequately treated. DESIGN: A questionnaire regarding medical history was sent to 2611 subjects who had been provided with a molecular genetic diagnosis of FH or FDB, and a blood sample was obtained for lipid measurements. RESULTS: 956 (36.6% of the 2611 subjects participated. The mean age for starting lipid-lowering therapy was 33.4 (±12.1 years. Among those below 18 years of age, only 20.4% were on lipid-lowering drugs, whereas 89.1% of those aged 18 and above were on lipid-lowering drugs. The mean levels of total serum cholesterol and LDL-cholesterol were 5.7 (±1.5 mmol/l and 3.9 (±1.3 mmol/l, respectively. Among those who were on lipid-lowering drugs, 29.0% and 12.2% had levels of LDL cholesterol below 3.0 mmol/l and 2.6 mmol/l, respectively. Only 47.3% of the 956 subjects were considered as being adequately treated largely due to a failure to titrate their drug regimens. From the use of cholesterol-years score, lipid-lowering therapy must start before the age of 20 in order to prevent the subjects from contracting premature coronary heart disease. CONCLUSION: The majority of FH/FDB subjects are being diagnosed late in life and are not being adequately treated. In order to prevent them from contracting premature coronary heart disease, it is key that levels of LDL cholesterol are normalized from a young age and that sufficient doses of lipid-lowering drugs are being used.

  11. An improved robust stability and robust stabilization method for linear discrete-time uncertain systems

    Institute of Scientific and Technical Information of China (English)

    Xianming ZHANG; Min WU; Jinhua SHE; Dongsheng HAN

    2007-01-01

    This paper addresses the problems of the robust stability and robust stabilization of a discrete-time system with polytopic uncertainties.A new and simple method is presented to directly decouple the Lyapunov matrix and the system dynamic matrix.Combining this method with the parameter-dependent Lyapunov function approach yields new criteria that include some existing ones as special cases.A numerical example illustrates the improvement over the existing ones.

  12. Robust Fault Detection Using Robust Z1 Estimation and Fuzzy Logic

    Science.gov (United States)

    Curry, Tramone; Collins, Emmanuel G., Jr.; Selekwa, Majura; Guo, Ten-Huei (Technical Monitor)

    2001-01-01

    This research considers the application of robust Z(sub 1), estimation in conjunction with fuzzy logic to robust fault detection for an aircraft fight control system. It begins with the development of robust Z(sub 1) estimators based on multiplier theory and then develops a fixed threshold approach to fault detection (FD). It then considers the use of fuzzy logic for robust residual evaluation and FD. Due to modeling errors and unmeasurable disturbances, it is difficult to distinguish between the effects of an actual fault and those caused by uncertainty and disturbance. Hence, it is the aim of a robust FD system to be sensitive to faults while remaining insensitive to uncertainty and disturbances. While fixed thresholds only allow a decision on whether a fault has or has not occurred, it is more valuable to have the residual evaluation lead to a conclusion related to the degree of, or probability of, a fault. Fuzzy logic is a viable means of determining the degree of a fault and allows the introduction of human observations that may not be incorporated in the rigorous threshold theory. Hence, fuzzy logic can provide a more reliable and informative fault detection process. Using an aircraft flight control system, the results of FD using robust Z(sub 1) estimation with a fixed threshold are demonstrated. FD that combines robust Z(sub 1) estimation and fuzzy logic is also demonstrated. It is seen that combining the robust estimator with fuzzy logic proves to be advantageous in increasing the sensitivity to smaller faults while remaining insensitive to uncertainty and disturbances.

  13. Robust Stackelberg game in communication systems

    CERN Document Server

    parsaeefard, saeedeh; Sharafat, Ahmad R

    2011-01-01

    This paper studies multi-user communication systems with two groups of users: leaders which possess system information, and followers which have no system information using the formulation of Stackelberg games. In such games, the leaders play and choose their actions based on their information about the system and the followers choose their actions myopically according to their observations of the aggregate impact of other users. However, obtaining the exact value of these parameters is not practical in communication systems. To study the effect of uncertainty and preserve the players' utilities in these conditions, we introduce a robust equilibrium for Stackelberg games. In this framework, the leaders' information and the followers' observations are uncertain parameters, and the leaders and the followers choose their actions by solving the worst-case robust optimizations. We show that the followers' uncertain parameters always increase the leaders' utilities and decrease the followers' utilities. Conversely,...

  14. Robust super-resolution without regularization

    Energy Technology Data Exchange (ETDEWEB)

    Pham, T Q [Canon Information Systems Research Australia, 1 Thomas Holt drive, North Ryde, NSW 2113 (Australia); Vliet, L J v [Quantitative Imaging Group, Department of Imaging Science and Technology, Faculty of Applied Sciences, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft (Netherlands); Schutte, K [Electro-Optics Group, TNO Defence, Security and Safety, PO Box 96864, 2509 JG The Hague (Netherlands)

    2008-07-15

    Super-resolution restoration is the problem of restoring a high-resolution scene from multiple degraded low-resolution images under motion. Due to imaging blur and noise, this problem is ill-posed. Additional constraints such as smoothness of the solution (i.e. regularization) is often required to obtain a stable solution. While regularizing the cost function is a standard practice in image restoration, we propose a restoration algorithm that does not require this extra regularization term. The robustness of the algorithm is achieved by a robust error norm that does not response to intensity outliers. With the outliers suppressed, our solution behaves similarly to a maximum-likelihood solution under the presence of Gaussian noise. The effectiveness of our algorithm is demonstrated with super-resolution restoration of real infrared image sequences under severe aliasing and intensity outliers.

  15. Robust Reconfiguration of A Distribution System

    Energy Technology Data Exchange (ETDEWEB)

    Moradzadeh, Benyamin [University of Tennessee, Knoxville (UTK); Tomsovic, Kevin [University of Tennessee, Knoxville (UTK)

    2017-01-01

    In this paper, a robust reconfiguration approach based on Mixed Integer Programming (MIP) is proposed to minimize loss in distribution systems. A Depth-First Search (DFS) algorithm to enumerate possible loops provides radiality constraint. This provides a general solution to the radiality constraint for distribution system reconfiguration/expansion problems. Still, imprecision and ambiguity in net loads, i.e. load minus renewable generation, due to lack of sufficient measurements and high utilization of demand response programs and renewable resources, creates challenges for effective reconfiguration. Deterministic optimization of reconfiguration may no lead to optimal/feasible results. Two methods to address these uncertainties are introduced in this paper: one, based on a stochastic MIP (SMIP) formulation and two, based on a fuzzy MIP (FMIP) formulation. Case studies demonstrate the robustness and efficiency of the proposed reconfiguration methods.

  16. The Robustness of High Danish National Happiness

    DEFF Research Database (Denmark)

    Hussain, M. Azhar

    2014-01-01

    Denmark’s top position in various rankings of country happiness is well-documented. This study goes beyond the national average comparisons and investigates whether Denmark’s top position is also found when we disaggregate data in line with social categories often used within the social sciences....... The central measure is the empirical probability that a given population subgroup in Denmark has significantly higher happiness compared to another country’s similar subgroup in a given year. All five rounds of the European Social Survey are used but only the sixteen countries that were surveyed in each...... of the five rounds are included in this study. The results show that Denmark’s position at the top of the happiness scale is also robust when we look at population subgroups, but not in the sense that Denmark dominates all countries for all years. Instead, a modified version of robustness is necessary...

  17. Robust Mesoscopic Superposition of Ultracold Atoms

    CERN Document Server

    Hallwood, David W; Brand, Joachim

    2010-01-01

    Quantum superpositions of macroscopically distinct states, as in Schroedinger's example of a dead and alive cat, are important for our understanding of quantum mechanics and carry great promise for enhanced precision measurement techniques. Due to their inherent fragility, the maximally entangled "NOON" states engineered in optics and spin systems for ultra-precise spectroscopy have been limited to 10 particles. The related mesoscopic superpositions of flux states consisting of 10^9 Cooper pairs observed in superconducting rings have proven more robust but their microscopic nature is debated. Binary superpositions with multiple ultra-cold atoms have not yet been seen and existing proposals suffer severe limitations due to decoherence and the unfavorable scaling of precision and time scales needed to produce these states. In this paper we show how robust superpositions of mesoscopic flow in a ring trap can be made with strongly-correlated ultra-cold atoms under one-dimensional confinement. We present a microsc...

  18. Robust Image Watermarking Based on Psychovisual Threshold

    Directory of Open Access Journals (Sweden)

    Ferda Ernawan

    2016-12-01

    Full Text Available Because of the facility of accessing and sharing digital images through the internet, digital images are often copied, edited and reused. Digital image watermarking is an approach to protect and manage digital images as intellectual property. The embedding of a natural watermark based on the properties of the human eye can be utilized to effectively hide a watermark image. This paper proposes a watermark embedding scheme based on the psychovisual threshold and edge entropy. The sensitivity of minor changes in DCT coefficients against JPEG quantization tables was investigated. A watermark embedding scheme was designed that offers good resistance against JPEG image compression. The proposed scheme was tested under different types of attacks. The experimental results indicated that the proposed scheme can achieve high imperceptibility and robustness against attacks. The watermark recovery process is also robust against attacks.

  19. Provably secure robust threshold partial blind signature

    Institute of Scientific and Technical Information of China (English)

    CAO Zhenfu; ZHU Haojin; LU Rongxing

    2006-01-01

    Threshold digital signature and blind signature are playing important roles in cryptography as well as in practical applications such as e-cash and e-voting systems.Over the past few years, many cryptographic researchers have made considerable headway in this field. However, to our knowledge, most of existing threshold blind signature schemes are based on the discrete logarithm problem. In this paper, we propose a new robust threshold partial blind signature scheme based on improved RSA cryptosystem.This scheme is the first threshold partial blind signature scheme based on factoring, and the robustness of threshold partial blind signature is also introduced. Moreover, in practical application, the proposed scheme will be especially suitable for blind signature-based voting systems with multiple administrators and secure electronic cash systems to prevent their abuse.

  20. Robust Clustering Using Outlier-Sparsity Regularization

    CERN Document Server

    Forero, Pedro A; Giannakis, Georgios B

    2011-01-01

    Notwithstanding the popularity of conventional clustering algorithms such as K-means and probabilistic clustering, their clustering results are sensitive to the presence of outliers in the data. Even a few outliers can compromise the ability of these algorithms to identify meaningful hidden structures rendering their outcome unreliable. This paper develops robust clustering algorithms that not only aim to cluster the data, but also to identify the outliers. The novel approaches rely on the infrequent presence of outliers in the data which translates to sparsity in a judiciously chosen domain. Capitalizing on the sparsity in the outlier domain, outlier-aware robust K-means and probabilistic clustering approaches are proposed. Their novelty lies on identifying outliers while effecting sparsity in the outlier domain through carefully chosen regularization. A block coordinate descent approach is developed to obtain iterative algorithms with convergence guarantees and small excess computational complexity with res...

  1. Efficient robust supervisors for discrete event systems

    Institute of Scientific and Technical Information of China (English)

    ECONOMACOS Christoforos E.; KOUMBOULIS Fotis N.

    2009-01-01

    This paper is a sequel to a previous publication by the same authors, in which an efficient modular solution to a robust supervisory control problem for discrete event systems modeled by finite automata with prefix-closed specification languages has been presented. This solution is based on a general recursive robust control scheme, which has been successfully applied to a number of problems. The additional contributions of the present paper are: (a) a slight generalization of the problem assumptions; (b) an alternative derivation of some of the results and an alternative formulation of the controller; (c) a detailed description of a very efficient on-line implementation algorithm; and (d) an illustrative practical example.

  2. Robust Metric Learning by Smooth Optimization

    CERN Document Server

    Huang, Kaizhu; Xu, Zenglin; Liu, Cheng-Lin

    2012-01-01

    Most existing distance metric learning methods assume perfect side information that is usually given in pairwise or triplet constraints. Instead, in many real-world applications, the constraints are derived from side information, such as users' implicit feedbacks and citations among articles. As a result, these constraints are usually noisy and contain many mistakes. In this work, we aim to learn a distance metric from noisy constraints by robust optimization in a worst-case scenario, to which we refer as robust metric learning. We formulate the learning task initially as a combinatorial optimization problem, and show that it can be elegantly transformed to a convex programming problem. We present an efficient learning algorithm based on smooth optimization [7]. It has a worst-case convergence rate of O(1/{\\surd}{\\varepsilon}) for smooth optimization problems, where {\\varepsilon} is the desired error of the approximate solution. Finally, our empirical study with UCI data sets demonstrate the effectiveness of ...

  3. Communicating via robust synchronization of chaotic lasers

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Gutierrez, R.M. [Engineering Faculty, Baja California Autonomous University (UABC), Km. 103 Carret. Tij-Ens., 22860 Ensenada, B.C. (Mexico); Posadas-Castillo, C. [Engineering Faculty, Baja California Autonomous University (UABC), Km. 103 Carret. Tij-Ens., 22860 Ensenada, B.C. (Mexico); FIME, Autonomous University of Nuevo Leon (UANL), Pedro de Alba, S.N., Cd. Universitaria, San Nicolas de los Garza, NL (Mexico); Lopez-Mancilla, D. [Departamento de Ciencias Exactas y Tecnologicas, Centro Universitario de los Lagos, Universidad de Guadalajara (CULagos-UdeG), Enrique Diaz de Leon s/n, 47460 Lagos de Moreno, Jal. (Mexico); Cruz-Hernandez, C. [Electronics and Telecommunications Department, Scientific Research and Advanced Studies of Ensenada (CICESE), Km. 107 Carret. Tij-Ens., 22860 Ensenada, B.C. (Mexico)], E-mail: ccruz@cicese.mx

    2009-10-15

    In this paper, the robust synchronization problem for coupled chaotic Nd:YAG lasers is addressed. We resort to complex systems theory to achieve chaos synchronization. Based on stability theory, it is shown that the state trajectories of the perturbed error synchronization are ultimately bounded, provided the unperturbed synchronization error system is exponentially stable, and some conditions on the bounds of the perturbation terms are satisfied. So that, encoding, transmission, and decoding in chaotic optical communications are presented. We analyze the transmission and recovery of encrypted information when parameter mismatches are considered. Computer simulations are provided to show the effectiveness of this robustness synchronization property, we present the encrypted transmission of image messages, and we show that, the transmitted image is faithfully recovered.

  4. Robustness studies on coal gasification process variables

    Directory of Open Access Journals (Sweden)

    RLJ Coetzer

    2004-12-01

    Full Text Available Optimisation of the Sasol-Lurgi gasification process was carried out by utilising the method of Factorial Experimental Design on the process variables of interest from a specifically equipped full-scale test gasifier. The process variables that govern gasification are not always fully controllable during normal operation. This paper discusses the application of statistical robustness studies as a method for determining the most efficient combination of process variables that might be hard-to-control during normal operation. Response surface models were developed in the process variables for each of the performance variables. It will be shown how statistical robustness studies provided the optimal conditions for sustainable gasifier operability and throughput. In particular, the optimum operability region is significantly expanded towards higher oxygen loads by changing and controlling the particle size distribution of the coal.

  5. Robust diffusion imaging framework for clinical studies

    CERN Document Server

    Maximov, Ivan I; Neuner, Irene; Shah, N Jon

    2015-01-01

    Clinical diffusion imaging requires short acquisition times and good image quality to permit its use in various medical applications. In turn, these demands require the development of a robust and efficient post-processing framework in order to guarantee useful and reliable results. However, multiple artefacts abound in in vivo measurements; from either subject such as cardiac pulsation, bulk head motion, respiratory motion and involuntary tics and tremor, or imaging hardware related problems, such as table vibrations, etc. These artefacts can severely degrade the resulting images and render diffusion analysis difficult or impossible. In order to overcome these problems, we developed a robust and efficient framework enabling the use of initially corrupted images from a clinical study. At the heart of this framework is an improved least trimmed squares diffusion tensor estimation algorithm that works well with severely degraded datasets with low signal-to-noise ratio. This approach has been compared with other...

  6. Robust Image Watermarking Using Discrete Wavelet Transform

    Directory of Open Access Journals (Sweden)

    Dhandapani Samiappan

    2011-01-01

    Full Text Available Problem statement: Digital Watermarking have gained popularity in recent years as a means of protecting multimedia data from illegal copying and unlawful reproduction. It is mainly used for copyright protection of multimedia data. Approach: In this study an image watermarking algorithm which is blind (do not require the presence of host image for detection and robust is proposed. Results: The proposed watermarking scheme embeds the watermark in the Discrete Wavelet Transform (DWT domain. The watermark is a binary logo and is embedded in the subband of the wavelet decomposition. Conclusion: This watermarking scheme is robust to several attacks like JPEG compression, rotation, Gaussian filtering, median filtering, cropping, scaling, sharpening, Gaussian noise and salt and pepper noise.

  7. ForBild: efficient robust image hashing

    Science.gov (United States)

    Steinebach, Martin; Liu, Huajian; Yannikos, York

    2012-03-01

    Forensic analysis of image sets today is most often done with the help of cryptographic hashes due to their efficiency, their integration in forensic tools and their excellent reliability in the domain of false detection alarms. A drawback of these hash methods is their fragility to any image processing operation. Even a simple re-compression with JPEG results in an image not detectable. A different approach is to apply image identification methods, allowing identifying illegal images by e.g. semantic models or facing detection algorithms. Their common drawback is a high computational complexity and significant false alarm rates. Robust hashing is a well-known approach sharing characteristics of both cryptographic hashes and image identification methods. It is fast, robust to common image processing and features low false alarm rates. To verify its usability in forensic evaluation, in this work we discuss and evaluate the behavior of an optimized block-based hash.

  8. Robust Parameter Coordination for Multidisciplinary Design

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    This paper introduced a robust parameter coordination method to analyze parameter uncertainties so as to predict conflicts and coordinate parameters in multidisciplinary design. The proposed method is based on constraints network, which gives a formulated model to analyze the coupling effects between design variables and product specifications. In this model, interval boxes are adopted to describe the uncertainty of design parameters quantitatively to enhance the design robustness. To solve this constraint network model, a general consistent algorithm framework is designed and implemented with interval arithmetic and the genetic algorithm, which can deal with both algebraic and ordinary differential equations. With the help of this method, designers could infer the consistent solution space from the given specifications. A case study involving the design of a bogie dumping system demonstrates the usefulness of this approach.

  9. A Robust Parsing Algorithm For Link Grammars

    CERN Document Server

    Grinberg, D; Sleator, D; Grinberg, Dennis; Lafferty, John; Sleator, Daniel

    1995-01-01

    In this paper we present a robust parsing algorithm based on the link grammar formalism for parsing natural languages. Our algorithm is a natural extension of the original dynamic programming recognition algorithm which recursively counts the number of linkages between two words in the input sentence. The modified algorithm uses the notion of a null link in order to allow a connection between any pair of adjacent words, regardless of their dictionary definitions. The algorithm proceeds by making three dynamic programming passes. In the first pass, the input is parsed using the original algorithm which enforces the constraints on links to ensure grammaticality. In the second pass, the total cost of each substring of words is computed, where cost is determined by the number of null links necessary to parse the substring. The final pass counts the total number of parses with minimal cost. All of the original pruning techniques have natural counterparts in the robust algorithm. When used together with memoization...

  10. Model predictive control classical, robust and stochastic

    CERN Document Server

    Kouvaritakis, Basil

    2016-01-01

    For the first time, a textbook that brings together classical predictive control with treatment of up-to-date robust and stochastic techniques. Model Predictive Control describes the development of tractable algorithms for uncertain, stochastic, constrained systems. The starting point is classical predictive control and the appropriate formulation of performance objectives and constraints to provide guarantees of closed-loop stability and performance. Moving on to robust predictive control, the text explains how similar guarantees may be obtained for cases in which the model describing the system dynamics is subject to additive disturbances and parametric uncertainties. Open- and closed-loop optimization are considered and the state of the art in computationally tractable methods based on uncertainty tubes presented for systems with additive model uncertainty. Finally, the tube framework is also applied to model predictive control problems involving hard or probabilistic constraints for the cases of multiplic...

  11. The robustness and innovability of protein folds.

    Science.gov (United States)

    Tóth-Petróczy, Agnes; Tawfik, Dan S

    2014-06-01

    Assignment of protein folds to functions indicates that >60% of folds carry out one or two enzymatic functions, while few folds, for example, the TIM-barrel and Rossmann folds, exhibit hundreds. Are there structural features that make a fold amenable to functional innovation (innovability)? Do these features relate to robustness--the ability to readily accumulate sequence changes? We discuss several hypotheses regarding the relationship between the architecture of a protein and its evolutionary potential. We describe how, in a seemingly paradoxical manner, opposite properties, such as high stability and rigidity versus conformational plasticity and structural order versus disorder, promote robustness and/or innovability. We hypothesize that polarity--differentiation and low connectivity between a protein's scaffold and its active-site--is a key prerequisite for innovability.

  12. ROBUST OPTIMUM DESIGN OF LAMINATED COMPOSITE PLATES

    Institute of Scientific and Technical Information of China (English)

    WangXiangyang; ChenJianqiao

    2004-01-01

    A last-ply failure (LPF) analysis method for laminated composite plates is incorporated into the finite element code-ANSYS, and a robust optimum design method is presented. The composite structure is analyzed by considering both in-plane and out-of-plane loads. For a lamina,two major failure modes are considered: matrix failure and fiber breakage that axe characterized by the proper strength criteria in the literature. When a lamina has failed, the laminate stiffness is modified to reflect the damage, and stresses in the structure are re-analyzed. This procedure is repeatedly performed until the whole structure fails and thus the ultimate strength is determined.A structural optimization problem is solved with the fiber orientation and the lamina thickness as the design variables and the LPF load as the objective. Finally, the robust optimum design method for laminates is presented and discussed.

  13. Doubly Constrained Robust Blind Beamforming Algorithm

    Directory of Open Access Journals (Sweden)

    Xin Song

    2013-01-01

    Full Text Available We propose doubly constrained robust least-squares constant modulus algorithm (LSCMA to solve the problem of signal steering vector mismatches via the Bayesian method and worst-case performance optimization, which is based on the mismatches between the actual and presumed steering vectors. The weight vector is iteratively updated with penalty for the worst-case signal steering vector by the partial Taylor-series expansion and Lagrange multiplier method, in which the Lagrange multipliers can be optimally derived and incorporated at each step. A theoretical analysis for our proposed algorithm in terms of complexity cost, convergence performance, and SINR performance is presented in this paper. In contrast to the linearly constrained LSCMA, the proposed algorithm provides better robustness against the signal steering vector mismatches, yields higher signal captive performance, improves greater array output SINR, and has a lower computational cost. The simulation results confirm the superiority of the proposed algorithm on beampattern control and output SINR enhancement.

  14. Robust H∞ control for networked control systems

    Institute of Scientific and Technical Information of China (English)

    Ma Weiguo; Shao Cheng

    2008-01-01

    The robust H∞ control for networked control systems with both stochastic network-induced delay and data packet dropout is studied.When data are transmitted over network,the stochastic data packet dropout process can be described by a two-state Markov chain.The networked control systems with stochastic network-induced delay and data packet dropout are modeled as a discrete time Markov jump linear system with two operation modes.The sufficient condition of robust H∞ control for networked control systems stabilized by state feedback controller is presented in terms of linear matrix inequality.The state feedback controller can be constructed via the solution of a set of linear matrix inequalities.An example is given to verify the effectiveness of the method proposed.

  15. Design of Robust Neural Network Classifiers

    DEFF Research Database (Denmark)

    Larsen, Jan; Andersen, Lars Nonboe; Hintz-Madsen, Mads

    1998-01-01

    a modified likelihood function which incorporates the potential risk of outliers in the data. This leads to the introduction of a new parameter, the outlier probability. Designing the neural classifier involves optimization of network weights as well as outlier probability and regularization parameters. We...... suggest to adapt the outlier probability and regularisation parameters by minimizing the error on a validation set, and a simple gradient descent scheme is derived. In addition, the framework allows for constructing a simple outlier detector. Experiments with artificial data demonstrate the potential......This paper addresses a new framework for designing robust neural network classifiers. The network is optimized using the maximum a posteriori technique, i.e., the cost function is the sum of the log-likelihood and a regularization term (prior). In order to perform robust classification, we present...

  16. Robust and Flexible Scheduling with Evolutionary Computation

    DEFF Research Database (Denmark)

    Jensen, Mikkel T.

    (schedules expected to perform well after some degree of modification when the environment changes). This thesis presents two fundamentally different approaches for scheduling job shops facing machine breakdowns. The first method is called neighbourhood based robustness and is based on an idea of minimising...... environments include machine breakdowns, uncertain processing times, workers getting sick, materials being delayed and the appearance of new jobs. These possible environmental changes mean that a schedule which was optimal for the information available at the time of scheduling can end up being highly...... suboptimal when it is implemented and subjected to the uncertainty of the real world. For this reason it is very important to find methods capable of creating robust schedules (schedules expected to perform well after a minimal amount of modification when the environment changes) or flexible schedules...

  17. Assortativity Decreases the Robustness of Interdependent Networks

    CERN Document Server

    Zhou, Di; Scala, Antonio; Stanley, H Eugene

    2012-01-01

    The protection of critical infrastructures is one of the highest priorities in our technological society. It was recently recognized that interdependencies among different networks can play a crucial role in triggering cascading failures and hence system-wide disasters. A recent model shows how pairs of interdependent networks can exhibit an abrupt percolation transition as failures accumulate. We report on the effects of topology on failure propagation for a model system consisting of two interdependent networks. We find that the internal node correlations in each of the two interdependent networks significantly changes the critical density of failures that triggers the total disruption of the two-network system. We find, in particular, that the assortativity within a single network decreases the robustness of the entire system. The results of this study on the influence of assortativity may provide insights into ways of improving the robustness of network architecture, and thus enhance the level of protecti...

  18. Phentolamine as a treatment for poor mixing in transposition of the great arteries with adequate intraatrial communication.

    Science.gov (United States)

    Galal, M O; El-Naggar, W I; Sharfi, M H

    2005-01-01

    Patients with transposition of the great arteries often show poor mixing for different reasons, even after adequate balloon atrial septostomy. We present a patient with such a lesion whose clinical status improved dramatically after phentolamine was applied. We believe this improvement is due to reduction in afterload caused by the alpha(2) blocker and also possibly as a response to a presumptive effect of the drug on the diastolic function of the right ventricle, allowing more left-to-right shunt across the atrial septal defect. Both phenomena can improve cardiac output in such a situation.

  19. Matlab as a robust control design tool

    Science.gov (United States)

    Gregory, Irene M.

    1994-01-01

    This presentation introduces Matlab as a tool used in flight control research. The example used to illustrate some of the capabilities of this software is a robust controller designed for a single stage to orbit air breathing vehicles's ascent to orbit. The global requirements of the controller are to stabilize the vehicle and follow a trajectory in the presence of atmospheric disturbances and strong dynamic coupling between airframe and propulsion.

  20. Adding query privacy to robust DHTs

    DEFF Research Database (Denmark)

    Backes, Michael; Goldberg, Ian; Kate, Aniket

    2012-01-01

    intermediate peers that (help to) route the queries towards their destinations. In this paper, we satisfy this requirement by presenting an approach for providing privacy for the keys in DHT queries. We use the concept of oblivious transfer (OT) in communication over DHTs to preserve query privacy without...... privacy over robust DHTs. Finally, we compare the performance of our privacy-preserving protocols with their more privacy-invasive counterparts. We observe that there is no increase in the message complexity...

  1. Robust Adaptive Control of Hypnosis During Anesthesia

    Science.gov (United States)

    2007-11-02

    1 of 4 ROBUST ADAPTIVE CONTROL OF HYPNOSIS DURING ANESTHESIA Pascal Grieder1, Andrea Gentilini1, Manfred Morari1, Thomas W. Schnider2 1ETH Zentrum...A closed-loop controller for hypnosis was designed and validated on humans at our laboratory. The controller aims at regulat- ing the Bispectral Index...BIS) - a surro- gate measure of hypnosis derived from the electroencephalogram of the patient - with the volatile anesthetic isoflurane administered

  2. Stability Constraints for Robust Model Predictive Control

    Directory of Open Access Journals (Sweden)

    Amanda G. S. Ottoni

    2015-01-01

    Full Text Available This paper proposes an approach for the robust stabilization of systems controlled by MPC strategies. Uncertain SISO linear systems with box-bounded parametric uncertainties are considered. The proposed approach delivers some constraints on the control inputs which impose sufficient conditions for the convergence of the system output. These stability constraints can be included in the set of constraints dealt with by existing MPC design strategies, in this way leading to the “robustification” of the MPC.

  3. Helicopter vibration reduction using robust control

    OpenAIRE

    Mannchen, Thomas

    2003-01-01

    This dissertation presents a control law for helicopters to reduce vibration and to increase damping using individual blade control. H-infinity control synthesis is used to develop a robust controller usable in different operating conditions with different helicopter flight speeds. The control design is applied in simulation to the four-blade BO 105 helicopter rotor, which is equipped with an individual blade control system, where the pitch rod links are replaced by hydraulic actuators, allow...

  4. Robust solutions of Uncertain Capacity inventory control

    Institute of Scientific and Technical Information of China (English)

    Yajing Li

    2013-01-01

    This paper analyzes the uncertainties of air cargo and applies revenue management to solve the problem of air cargo capacity control.A robust capacity al ocation model for a multiple-leg with multiple shipment types is established,which describe uncertainty of these parameters as a number of discrete scenarios,and obtain the optimal al ocation with Mutation Particle Swarm Optimization.Simulation experiments show that this method can balance uncertainty of the model effectively and accord with actual situation.

  5. A robust adaptive controller for robot manipulators

    OpenAIRE

    1992-01-01

    The authors propose a globally convergent adaptive control scheme for robot motion control with the following features: first, the adaptation law processes enhanced robustness with respect to noisy velocity measurements; secondly, the controller does not require the inclusion of high-gain loops that may excite the unmodeled dynamics and amplify the noise level; thirdly the authors derive for the known parameter design a relationship between compensator gains and closed-loop convergence rates ...

  6. Robust Satellite Communications Under Hostile Interference

    Science.gov (United States)

    2016-05-20

    extremely hardened radios that sacrifice communications performance for more advanced jamming protection. To provide an escape from this trend, we...being targeted, the common three being: communications , radar, and radio navigation (e.g., Global Positioning System (GPS) and Global Navigation...AFRL-RV-PS- AFRL-RV-PS- TR-2016-0079 TR-2016-0079 ROBUST SATELLITE COMMUNICATIONS UNDER HOSTILE INTERFERENCE Marc Lichtman and Jeffrey Reed

  7. Robust Multi-Agent Sensor Network Systems

    Science.gov (United States)

    2012-05-08

    Decision and Control December 15-17, 2010 Hilton Atlanta Hotel , Atlanta, GA, USA 978-1-4244-7744-9/10/$26.00 ©2010 IEEE 402 II. PRELIMINARIES We will...interference caused by other simultaneously active transmissions. • We derived analytical expression for the capacity of the above network. • Considering...which are robust against the loss of multiple agents. A formation is said to be rigid if by actively maintaining a designated set of inter-agent

  8. Robust synthesis for real-time systems

    DEFF Research Database (Denmark)

    Larsen, Kim Guldstrand; Legay, Axel; Traonouez, Louis-Marie;

    2014-01-01

    Specification theories for real-time systems allow reasoning about interfaces and their implementation models, using a set of operators that includes satisfaction, refinement, logical and parallel composition. To make such theories applicable throughout the entire design process from an abstract ...... strategies in timed games. Finally, we consider the parametric robustness problem and propose a counter-example refinement heuristic for computing safe perturbation values....

  9. The Evolutionary Robustness of Forgiveness and Cooperation

    CERN Document Server

    Bó, Pedro Dal

    2012-01-01

    We study the evolutionary robustness of strategies in infinitely repeated prisoners' dilemma games in which players make mistakes with a small probability and are patient. The evolutionary process we consider is given by the replicator dynamics. We show that there are strategies with a uniformly large basin of attraction independently of the size of the population. Moreover, we show that those strategies forgive defections and, assuming that they are symmetric, they cooperate.

  10. Analysis and Synthesis of Robust Data Structures

    Science.gov (United States)

    1990-08-01

    1.3.2 Multiversion Software. .. .. .. .. .. .... .. ... .. ...... 5 1.3.3 Robust Data Structure .. .. .. .. .. .. .. .. .. ... .. ..... 6 1.4...context are 0 multiversion software, which is an adaptation oi N-modulo redundancy (NMR) tech- nique. * recovery blocks, which is an adaptation of...implementations using these features for such a hybrid approach. 1.3.2 Multiversion Software Avizienis [AC77] was the first to adapt NMR technique into

  11. Robust topology design of periodic grating surfaces

    DEFF Research Database (Denmark)

    Friis, Kasper Storgaard; Sigmund, Ole

    2012-01-01

    Modern nanoscale manufacturing techniques allow for a high degree of flexibility in designing surface microstructures and nanostructures. Injection molding of nanosized features allows for mass production of plastic components with a tailored nanostructure producing specific optical effects...... depending on the purpose. This work details the use of topology optimization for designing periodic polymer grating surfaces with complex optical properties. A method based on robust topology optimization is formulated for designing the nanostructure of plastic surfaces with extreme reflection...

  12. Robust frame-dependent video watermarking

    Science.gov (United States)

    Holliman, Matthew J.; Macy, William W.; Yeung, Minerva M.

    2000-05-01

    In this paper, we describe some of the problems associated with watermarking key management, with particular attention to the case of video. We also describe a possible solution to the problem, which is that of image-dependent watermarking, and briefly discuss some of the possible advantages to be gained from adopting such an approach. The paper also presents a simple, efficient means of robustly extracting bits from a video sequence. The algorithm has applications to secure, oblivious video watermark detection.

  13. Robust Multilayer Insulation for Cryogenic Systems

    Science.gov (United States)

    Fesmire, J. E.; Scholtens, B. F.; Augustynowicz, S. D.

    2007-01-01

    New requirements for thermal insulation include robust Multilayer insulation (MU) systems that work for a range of environments from high vacuum to no vacuum. Improved MLI systems must be simple to install and maintain while meeting the life-cycle cost and thermal performance objectives. Performance of actual MLI systems has been previously shown to be much worse than ideal MLI. Spacecraft that must contain cryogens for both lunar service (high vacuum) and ground launch operations (no vacuum) are planned. Future cryogenic spacecraft for the soft vacuum environment of Mars are also envisioned. Industry products using robust MLI can benefit from improved cost-efficiency and system safety. Novel materials have been developed to operate as excellent thermal insulators at vacuum levels that are much less stringent than the absolute high vacuum requirement of current MLI systems. One such robust system, Layered Composite Insulation (LCI), has been developed by the Cryogenics Test Laboratory at NASA Kennedy Space Center. The experimental testing and development of LCI is the focus of this paper. LCI thermal performance under cryogenic conditions is shown to be six times better than MLI at soft vacuum and similar to MLI at high vacuum. The experimental apparent thermal conductivity (k-value) and heat flux data for LCI systems are compared with other MLI systems.

  14. Robustness of airline alliance route networks

    Science.gov (United States)

    Lordan, Oriol; Sallan, Jose M.; Simo, Pep; Gonzalez-Prieto, David

    2015-05-01

    The aim of this study is to analyze the robustness of the three major airline alliances' (i.e., Star Alliance, oneworld and SkyTeam) route networks. Firstly, the normalization of a multi-scale measure of vulnerability is proposed in order to perform the analysis in networks with different sizes, i.e., number of nodes. An alternative node selection criterion is also proposed in order to study robustness and vulnerability of such complex networks, based on network efficiency. And lastly, a new procedure - the inverted adaptive strategy - is presented to sort the nodes in order to anticipate network breakdown. Finally, the robustness of the three alliance networks are analyzed with (1) a normalized multi-scale measure of vulnerability, (2) an adaptive strategy based on four different criteria and (3) an inverted adaptive strategy based on the efficiency criterion. The results show that Star Alliance has the most resilient route network, followed by SkyTeam and then oneworld. It was also shown that the inverted adaptive strategy based on the efficiency criterion - inverted efficiency - shows a great success in quickly breaking networks similar to that found with betweenness criterion but with even better results.

  15. Robustness analysis for real parametric uncertainty

    Science.gov (United States)

    Sideris, Athanasios

    1989-01-01

    Some key results in the literature in the area of robustness analysis for linear feedback systems with structured model uncertainty are reviewed. Some new results are given. Model uncertainty is described as a combination of real uncertain parameters and norm bounded unmodeled dynamics. Here the focus is on the case of parametric uncertainty. An elementary and unified derivation of the celebrated theorem of Kharitonov and the Edge Theorem is presented. Next, an algorithmic approach for robustness analysis in the cases of multilinear and polynomic parametric uncertainty (i.e., the closed loop characteristic polynomial depends multilinearly and polynomially respectively on the parameters) is given. The latter cases are most important from practical considerations. Some novel modifications in this algorithm which result in a procedure of polynomial time behavior in the number of uncertain parameters is outlined. Finally, it is shown how the more general problem of robustness analysis for combined parametric and dynamic (i.e., unmodeled dynamics) uncertainty can be reduced to the case of polynomic parametric uncertainty, and thus be solved by means of the algorithm.

  16. Tension and robustness in multitasking cellular networks.

    Directory of Open Access Journals (Sweden)

    Jeffrey V Wong

    Full Text Available Cellular networks multitask by exhibiting distinct, context-dependent dynamics. However, network states (parameters that generate a particular dynamic are often sub-optimal for others, defining a source of "tension" between them. Though multitasking is pervasive, it is not clear where tension arises, what consequences it has, and how it is resolved. We developed a generic computational framework to examine the source and consequences of tension between pairs of dynamics exhibited by the well-studied RB-E2F switch regulating cell cycle entry. We found that tension arose from task-dependent shifts in parameters associated with network modules. Although parameter sets common to distinct dynamics did exist, tension reduced both their accessibility and resilience to perturbation, indicating a trade-off between "one-size-fits-all" solutions and robustness. With high tension, robustness can be preserved by dynamic shifting of modules, enabling the network to toggle between tasks, and by increasing network complexity, in this case by gene duplication. We propose that tension is a general constraint on the architecture and operation of multitasking biological networks. To this end, our work provides a framework to quantify the extent of tension between any network dynamics and how it affects network robustness. Such analysis would suggest new ways to interfere with network elements to elucidate the design principles of cellular networks.

  17. Sparse alignment for robust tensor learning.

    Science.gov (United States)

    Lai, Zhihui; Wong, Wai Keung; Xu, Yong; Zhao, Cairong; Sun, Mingming

    2014-10-01

    Multilinear/tensor extensions of manifold learning based algorithms have been widely used in computer vision and pattern recognition. This paper first provides a systematic analysis of the multilinear extensions for the most popular methods by using alignment techniques, thereby obtaining a general tensor alignment framework. From this framework, it is easy to show that the manifold learning based tensor learning methods are intrinsically different from the alignment techniques. Based on the alignment framework, a robust tensor learning method called sparse tensor alignment (STA) is then proposed for unsupervised tensor feature extraction. Different from the existing tensor learning methods, L1- and L2-norms are introduced to enhance the robustness in the alignment step of the STA. The advantage of the proposed technique is that the difficulty in selecting the size of the local neighborhood can be avoided in the manifold learning based tensor feature extraction algorithms. Although STA is an unsupervised learning method, the sparsity encodes the discriminative information in the alignment step and provides the robustness of STA. Extensive experiments on the well-known image databases as well as action and hand gesture databases by encoding object images as tensors demonstrate that the proposed STA algorithm gives the most competitive performance when compared with the tensor-based unsupervised learning methods.

  18. Mutational robustness of gene regulatory networks.

    Directory of Open Access Journals (Sweden)

    Aalt D J van Dijk

    Full Text Available Mutational robustness of gene regulatory networks refers to their ability to generate constant biological output upon mutations that change network structure. Such networks contain regulatory interactions (transcription factor-target gene interactions but often also protein-protein interactions between transcription factors. Using computational modeling, we study factors that influence robustness and we infer several network properties governing it. These include the type of mutation, i.e. whether a regulatory interaction or a protein-protein interaction is mutated, and in the case of mutation of a regulatory interaction, the sign of the interaction (activating vs. repressive. In addition, we analyze the effect of combinations of mutations and we compare networks containing monomeric with those containing dimeric transcription factors. Our results are consistent with available data on biological networks, for example based on evolutionary conservation of network features. As a novel and remarkable property, we predict that networks are more robust against mutations in monomer than in dimer transcription factors, a prediction for which analysis of conservation of DNA binding residues in monomeric vs. dimeric transcription factors provides indirect evidence.

  19. Efficient nearest neighbors via robust sparse hashing.

    Science.gov (United States)

    Cherian, Anoop; Sra, Suvrit; Morellas, Vassilios; Papanikolopoulos, Nikolaos

    2014-08-01

    This paper presents a new nearest neighbor (NN) retrieval framework: robust sparse hashing (RSH). Our approach is inspired by the success of dictionary learning for sparse coding. Our key idea is to sparse code the data using a learned dictionary, and then to generate hash codes out of these sparse codes for accurate and fast NN retrieval. But, direct application of sparse coding to NN retrieval poses a technical difficulty: when data are noisy or uncertain (which is the case with most real-world data sets), for a query point, an exact match of the hash code generated from the sparse code seldom happens, thereby breaking the NN retrieval. Borrowing ideas from robust optimization theory, we circumvent this difficulty via our novel robust dictionary learning and sparse coding framework called RSH, by learning dictionaries on the robustified counterparts of the perturbed data points. The algorithm is applied to NN retrieval on both simulated and real-world data. Our results demonstrate that RSH holds significant promise for efficient NN retrieval against the state of the art.

  20. Spatial stochastic dynamics enable robust cell polarization.

    Directory of Open Access Journals (Sweden)

    Michael J Lawson

    Full Text Available Although cell polarity is an essential feature of living cells, it is far from being well-understood. Using a combination of computational modeling and biological experiments we closely examine an important prototype of cell polarity: the pheromone-induced formation of the yeast polarisome. Focusing on the role of noise and spatial heterogeneity, we develop and investigate two mechanistic spatial models of polarisome formation, one deterministic and the other stochastic, and compare the contrasting predictions of these two models against experimental phenotypes of wild-type and mutant cells. We find that the stochastic model can more robustly reproduce two fundamental characteristics observed in wild-type cells: a highly polarized phenotype via a mechanism that we refer to as spatial stochastic amplification, and the ability of the polarisome to track a moving pheromone input. Moreover, we find that only the stochastic model can simultaneously reproduce these characteristics of the wild-type phenotype and the multi-polarisome phenotype of a deletion mutant of the scaffolding protein Spa2. Significantly, our analysis also demonstrates that higher levels of stochastic noise results in increased robustness of polarization to parameter variation. Furthermore, our work suggests a novel role for a polarisome protein in the stabilization of actin cables. These findings elucidate the intricate role of spatial stochastic effects in cell polarity, giving support to a cellular model where noise and spatial heterogeneity combine to achieve robust biological function.

  1. Distributed redundancy and robustness in complex systems

    KAUST Repository

    Randles, Martin

    2011-03-01

    The uptake and increasing prevalence of Web 2.0 applications, promoting new large-scale and complex systems such as Cloud computing and the emerging Internet of Services/Things, requires tools and techniques to analyse and model methods to ensure the robustness of these new systems. This paper reports on assessing and improving complex system resilience using distributed redundancy, termed degeneracy in biological systems, to endow large-scale complicated computer systems with the same robustness that emerges in complex biological and natural systems. However, in order to promote an evolutionary approach, through emergent self-organisation, it is necessary to specify the systems in an \\'open-ended\\' manner where not all states of the system are prescribed at design-time. In particular an observer system is used to select robust topologies, within system components, based on a measurement of the first non-zero Eigen value in the Laplacian spectrum of the components\\' network graphs; also known as the algebraic connectivity. It is shown, through experimentation on a simulation, that increasing the average algebraic connectivity across the components, in a network, leads to an increase in the variety of individual components termed distributed redundancy; the capacity for structurally distinct components to perform an identical function in a particular context. The results are applied to a specific application where active clustering of like services is used to aid load balancing in a highly distributed network. Using the described procedure is shown to improve performance and distribute redundancy. © 2010 Elsevier Inc.

  2. Robust disturbance rejection for flexible mechanical structures

    Science.gov (United States)

    Enzmann, Marc R.; Doeschner, Christian

    2000-06-01

    Topic of the presentation is a procedure to determine controller parameters using principles from Internal Model Control (IMC) in combination with Quantitative Feedback Theory (QFT) for robust vibration control of flexible mechanical structures. IMC design is based on a parameterization of all controllers that stabilize a given nominal plant, called the Q-parameter or Youla-parameter. It will be shown that it is possible to choose the controller structure and the Q- parameter in a very straightforward manner, so that a low order controller results, which stabilizes the given nominal model. Additional constraints can be implemented, so that the method allows for a direct and transparent trade-off between control performance and controller complexity and facilitates the inclusion of low-pass filters. In order to test (and if necessary augment) the inherent robust performance of the resulting controllers, boundaries based on the work of Kidron and Yaniv are calculated in the Nichols-Charts of the open loop and the complementary sensitivity function. The application of these boundaries is presented. Very simple uncertainty models for resonant modes are used to assess the robustness of the design. Using a simply structured plant as illustrative example we will demonstrate the design process. This will illuminate several important features of the design process, e.g. trade-off between conflicting objectives, trade- off between controller complexity and achievable performance.

  3. UNIX-based operating systems robustness evaluation

    Science.gov (United States)

    Chang, Yu-Ming

    1996-01-01

    Robust operating systems are required for reliable computing. Techniques for robustness evaluation of operating systems not only enhance the understanding of the reliability of computer systems, but also provide valuable feed- back to system designers. This thesis presents results from robustness evaluation experiments on five UNIX-based operating systems, which include Digital Equipment's OSF/l, Hewlett Packard's HP-UX, Sun Microsystems' Solaris and SunOS, and Silicon Graphics' IRIX. Three sets of experiments were performed. The methodology for evaluation tested (1) the exception handling mechanism, (2) system resource management, and (3) system capacity under high workload stress. An exception generator was used to evaluate the exception handling mechanism of the operating systems. Results included exit status of the exception generator and the system state. Resource management techniques used by individual operating systems were tested using programs designed to usurp system resources such as physical memory and process slots. Finally, the workload stress testing evaluated the effect of the workload on system performance by running a synthetic workload and recording the response time of local and remote user requests. Moderate to severe performance degradations were observed on the systems under stress.

  4. Decentralized robust guaranteed cost control for a class of interconnected singular large-scale systems with time-delay and parameter uncertainty

    Institute of Scientific and Technical Information of China (English)

    Wo Songlin; Shi Guodong; Zou Yun

    2007-01-01

    The decentralized robust guaranteed cost control problem is studied for a class ofinterconnected singular large-scale systems with time-delay and norm-bounded time-invariant parameter uncertainty under a given quadratic cost performance function. The problem that is addressed in this study is to design a decentralized robust guaranteed cost state feedback controller such that the closed-loop system is not only regular, impulse-free and stable, but also guarantees an adequate level of performance for all admissible uncertainties. A sufficient condition for the existence of the decentralized robust guaranteed cost state feedback controllers is proposed in terms of a linear matrix inequality (LMI) via LMI approach. When this condition is feasible, the desired state feedback decentralized robust guaranteed cost controller gain matrices can be obtained. Finally, an illustrative example is provided to demonstrate the effectiveness of the proposed approach.

  5. Early prevention of obesity

    Directory of Open Access Journals (Sweden)

    Claudio Maffeis

    2014-06-01

    Full Text Available Childhood obesity is the metabolic disorder with the highest prevalence in both children and adults. Urgency to treat and prevent childhood obesity is based on the clear evidence that obesity tends to track from childhood to adulthood, is associated to morbidity also in childhood and to long-term mortality. Early life, i.e., intrauterine life and the first two years, is a sensitive window for prevention. Anatomical and functional maturation of the hypothalamic structures devoted to regulating energy intake and expenditure and body size mainly occurs in the first 1,000 days of life. Therefore, factors affecting the foetal exposition to maternal metabolic environment and early postnatal nutrition are crucial in modulating the definition of the metabolic programming processes in the brain. Maternal diseases, mainly malnutrition for defect or excess, obesity and diabetes, placental disorders and dysfunctions, maternal use of alcohol and drugs, smoking, affect long term metabolic programming of the foetus with lifelong consequences. Similarly, early nutrition contributes to complete the long-term metabolic regulating framework initiated in the uterus. Breastfeeding, adequate weaning, attention to portion size and diet composition are potential tools for reducing the obesity risk later in childhood. Longitudinal randomized controlled studies are needed for exploring the efficacy of obesity prevention strategies initiated after conception.Proceedings of the 10th International Workshop on Neonatology · Cagliari (Italy · October 22nd-25th, 2014 · The last ten years, the next ten years in Neonatology Guest Editors: Vassilios Fanos, Michele Mussap, Gavino Faa, Apostolos Papageorgiou

  6. Vigorous cleaning and adequate ventilation are necessary to control an outbreak in a neonatal intensive care unit.

    Science.gov (United States)

    Shimono, Nobuyuki; Hayashi, Jun; Matsumoto, Hiroko; Miyake, Noriko; Uchida, Yujiro; Shimoda, Shinji; Furusyo, Norihiro; Akashi, Koichi

    2012-06-01

    An outbreak of Bacillus cereus (B. cereus) bacteremia occurred in our neonatal intensive care unit (NICU) in July 2005. Many strains of B. cereus were cultured from patient specimens, as well as from environmental samples such as the surfaces of instruments and air in the NICU. Some of these strains were analyzed by pulsed field gel electrophoresis, and several were confirmed to be identical. We speculated that the bacterial load in the environment had initially increased and then possibly spread throughout the NICU facility via the airflow of the ventilation system. For this reason, besides maintaining standard precautions, we performed a vigorous clean of the NICU, and covered the vents to prevent dust falling from them. These protective measures ended the outbreak. In the hospital environment, adequate ventilation is important, especially in single-occupancy isolation rooms and operating theaters. However, the criteria for the adequate ventilation of multioccupancy rooms for acute care environments such as the NICU have not yet been defined. We need to pay more attention to these environmental factors in order to avoid cross contamination and infectious outbreaks.

  7. Median Urinary Iodine Concentrations Are Indicative of Adequate Iodine Status among Women of Reproductive Age in Prey Veng, Cambodia

    Directory of Open Access Journals (Sweden)

    Crystal D. Karakochuk

    2016-03-01

    Full Text Available Iodine deficiency disorders are estimated to affect over 1.9 million people worldwide. Iodine deficiency is especially serious for women during pregnancy and lactation because of the negative consequences for both mother and infant. The aim of this cross-sectional study was to determine the median urinary iodine concentration (UIC as a population-level indicator of iodine status among rural women farmers of reproductive age (18–45 years in the province of Prey Veng, Cambodia. A total of 450 women provided a spot morning urine sample in 2012. Of those women, 93% (n = 420 were non-pregnant and 7% (n = 30 were pregnant at the time of collection. UIC was quantified using the Sandell-Kolthoff reaction with modifications. The median UIC of non-pregnant (139 μg/L and pregnant women (157 μg/L were indicative of adequate iodine status using the WHO/UNICEF/ICCIDD epidemiological criteria for both groups (median UIC between 100–199 and 150–249 μg/L, respectively. We conclude that non-pregnant and pregnant women in rural Prey Veng, Cambodia had adequate iodine status based on single spot morning urine samples collected in 2012. More research is warranted to investigate iodine status among larger and more representative populations of women in Cambodia, especially in light of recent policy changes to the national program for universal salt iodization.

  8. Exercise prescription for the older population: The interactions between physical activity, sedentary time, and adequate nutrition in maintaining musculoskeletal health.

    Science.gov (United States)

    Shad, Brandon J; Wallis, Gareth; van Loon, Luc J C; Thompson, Janice L

    2016-11-01

    Regular physical activity (PA) promotes musculoskeletal health in older adults. However, the majority of older individuals do not meet current PA guidelines and are also highly sedentary. Emerging evidence indicates that large amounts of sedentary time accelerate the loss of skeletal muscle mass (i.e., sarcopenia) and physical function with advancing age. However, current PA recommendations for sedentary time are non-specific (i.e., keep sedentary time to a minimum). Research indicates that physical inactivity and large amounts of sedentary time accelerate sarcopenic muscle loss by inducing skeletal muscle 'anabolic resistance'. These findings suggest a critical interaction between engaging in 'sufficient' levels of PA, minimising sedentary time, and consuming 'adequate' nutrition to promote optimal musculoskeletal health in older adults. However, current PA recommendations do not take into account the important role that nutrition plays in ensuring older adults can maximise the benefits from the PA in which they engage. The aim of this narrative review is: (1) to briefly summarise the evidence used to inform current public health recommendations for PA and sedentary time in older adults; and (2) to discuss the presence of 'anabolic resistance' in older adults, highlighting the importance of regular PA and minimising sedentary behaviour. It is imperative that the synergy between PA, minimising sedentary behaviour and adequate nutrition is integrated into future PA guidelines to promote optimal musculoskeletal health and metabolic responses in the growing ageing population.

  9. Adequate Vitamin D Intake but Low Serum Levels in Pediatric Asthma Patients: A Pilot Study, Alberta Children’s Hospital

    Directory of Open Access Journals (Sweden)

    Sarah Howe McKenna

    2016-01-01

    Full Text Available Background. We assessed vitamin D intakes and serum 25(OH vitamin D levels in pediatric asthma patients on moderate-to-high dose inhaled steroids and compared them to published findings of healthy children in our city. Methods. Parents and/or patients were interviewed to estimate the children’s vitamin D intakes from foods and supplements (using an adapted validated food frequency questionnaire and asthma duration and management. Vitamin D status: serum 25-hyroxy vitamin D (25(OHD was obtained from the medical records. Results. Vitamin D intakes from food and supplements of the asthma patients (n=20, 742 ± 185 IU/day were significantly higher compared to healthy Canadian children (n=1442, 229 ± 121 IU/day. Despite higher vitamin D intakes, the children had nonsignificantly lower serum 25(OH vitamin D levels compared to the comparison group. Serum 25(OHD levels increased by 3.6 nmol/L with each 100 IU of vitamin D intake (95% Confidence interval = 2.0–4.0, R2 = 0.931, and p=0.001. Conclusion. Since adequate vitamin D status in asthma patients is necessary to support bone mineral accretion, it is important to achieve adequate vitamin D status by checking serum 25(OHD status and supplement accordingly.

  10. [The global and national context regarding the challenges involved in ensuring adequate access to water for human consumption].

    Science.gov (United States)

    Augusto, Lia Giraldo da Silva; Gurgel, Idê Gomes Dantas; Câmara Neto, Henrique Fernandes; de Melo, Carlos Henrique; Costa, André Monteiro

    2012-06-01

    The scope of this article is to analyze the challenges involved in ensuring access to water for human consumption taking the international and national context into consideration. Based on the UN declaration that access to safe and clean drinking water is a fundamental human right, vulnerabilities are identified that can consist in restrictions to access to adequate supplies. The distribution of water and the population across the planet, pollution, inadequate policies and management lead to environmental injustice. The iniquity of access to water constitutes the contemporary water crisis. From the 1980s onwards, the transnational water market emerged for private control that occurs at three main levels: surface and underground water sources; bottled water; and public water supply services. The conflicts of the multiple uses of water resources, the market and environmental problems have contributed to rendering the health of the population and ecosystems vulnerable. Adequate public policies are essential to ensure the basic human right to access to safe and clean drinking water.

  11. Median Urinary Iodine Concentrations Are Indicative of Adequate Iodine Status among Women of Reproductive Age in Prey Veng, Cambodia.

    Science.gov (United States)

    Karakochuk, Crystal D; Michaux, Kristina D; Chai, Tze L; Chan, Benny B; Whitfield, Kyly C; Barr, Susan I; McLean, Judy; Talukder, Aminuzzaman; Hou, Kroeun; Ly, Sokhoing; Green, Tim J

    2016-03-03

    Iodine deficiency disorders are estimated to affect over 1.9 million people worldwide. Iodine deficiency is especially serious for women during pregnancy and lactation because of the negative consequences for both mother and infant. The aim of this cross-sectional study was to determine the median urinary iodine concentration (UIC) as a population-level indicator of iodine status among rural women farmers of reproductive age (18-45 years) in the province of Prey Veng, Cambodia. A total of 450 women provided a spot morning urine sample in 2012. Of those women, 93% (n = 420) were non-pregnant and 7% (n = 30) were pregnant at the time of collection. UIC was quantified using the Sandell-Kolthoff reaction with modifications. The median UIC of non-pregnant (139 μg/L) and pregnant women (157 μg/L) were indicative of adequate iodine status using the WHO/UNICEF/ICCIDD epidemiological criteria for both groups (median UIC between 100-199 and 150-249 μg/L, respectively). We conclude that non-pregnant and pregnant women in rural Prey Veng, Cambodia had adequate iodine status based on single spot morning urine samples collected in 2012. More research is warranted to investigate iodine status among larger and more representative populations of women in Cambodia, especially in light of recent policy changes to the national program for universal salt iodization.

  12. Routine supplementation does not warrant the nutritional status of vitamin D adequate after gastric bypass Roux-en-Y

    Directory of Open Access Journals (Sweden)

    Cintia Leticia da Rosa

    2013-02-01

    Full Text Available Bariatric surgery can lead to nutritional deficiencies, including those related to bone loss. The aim of this study was to evaluate serum concentrations of calcium, vitamin D and PTH in obese adults before and six months after gastric bypass surgery in Roux-en-Y (RYGB and evaluate the doses of calcium and vitamin D supplementation after surgery. Methods: Retrospective longitudinal study of adult patients of both sexes undergoing RYGB. We obtained data on weight, height, BMI and serum concentrations of 25-hydroxyvitamin D, ionized calcium and PTH. Following surgery, patients received dietary supplementation daily 500 mg calcium carbonate and 400 IU vitamin D. Results: We studied 56 women and 27 men. Preoperative serum concentrations of vitamin D were inadequate in 45% of women and 37% of men, while in the postoperative period 91% of women and 85% of men had deficiency of this vitamin. No change in serum calcium was found before and after surgery. Serum PTH preoperatively remained adequate in 89% of individuals of both sexes. After surgery serum concentrations remained adequate and 89% women and 83% men evaluated. Conclusion: Obesity appears to be a risk factor for the development of vitamin D. The results show that supplementation routine postoperative was unable to treat and prevent vitamin D deficiency in obese adults undergoing RYGB.

  13. Readiness to adopt adequate postural habits: an application of the Transtheoretical Model in the context of back pain prevention.

    Science.gov (United States)

    Keller, S; Herda, C; Ridder, K; Basler, H D

    2001-02-01

    Based on a biomechanical model, an adequate body posture can contribute to the prevention of back pain and back pain chronicity. This study examines the explanatory value of the Transtheoretical Model (TTM) for the adoption of adequate postural habits in a cross-sectional sample of 149 employees of a German administration unit (mean age 40.2 years, 50% female). Using newly developed instruments with satisfactory psychometric properties, basic assumptions of the TTM could be confirmed: self-efficacy and the perceived pros for maintaining a good body posture increased significantly across the stages, while the perceived cons decreased. Additionally, the use of preventive strategies for back pain prevention increased linearly and significantly across the stages of change. The study supports the applicability of the TTM for postural behavior. Considering stages of change as an intervening variable may contribute to clarifying the relationship between participation in low back schools and prevention of back pain chronicity. Longitudinal and intervention study data are needed to support these assumptions.

  14. Automated robust registration of grossly misregistered whole-slide images with varying stains

    Science.gov (United States)

    Litjens, G.; Safferling, K.; Grabe, N.

    2016-03-01

    Cancer diagnosis and pharmaceutical research increasingly depend on the accurate quantification of cancer biomarkers. Identification of biomarkers is usually performed through immunohistochemical staining of cancer sections on glass slides. However, combination of multiple biomarkers from a wide variety of immunohistochemically stained slides is a tedious process in traditional histopathology due to the switching of glass slides and re-identification of regions of interest by pathologists. Digital pathology now allows us to apply image registration algorithms to digitized whole-slides to align the differing immunohistochemical stains automatically. However, registration algorithms need to be robust to changes in color due to differing stains and severe changes in tissue content between slides. In this work we developed a robust registration methodology to allow for fast coarse alignment of multiple immunohistochemical stains to the base hematyoxylin and eosin stained image. We applied HSD color model conversion to obtain a less stain color dependent representation of the whole-slide images. Subsequently, optical density thresholding and connected component analysis were used to identify the relevant regions for registration. Template matching using normalized mutual information was applied to provide initial translation and rotation parameters, after which a cost function-driven affine registration was performed. The algorithm was validated using 40 slides from 10 prostate cancer patients, with landmark registration error as a metric. Median landmark registration error was around 180 microns, which indicates performance is adequate for practical application. None of the registrations failed, indicating the robustness of the algorithm.

  15. Importance of adequate immunosuppressive therapy for the recovery of patients with "life-threatening" severe exacerbation of chronic hepatitis B

    Institute of Scientific and Technical Information of China (English)

    Keiichi Fujiwara; Osamu Yokosuka; Hiroshige Kojima; Tatsuo Kanda; Hiromitsu Saisho; Hiroyuki Hirasawa; Hiroshi Suzuki

    2005-01-01

    AIM: Hepatitis B virus (HBV) re-activation often occurs spontaneously or after withdrawal of immunosuppressive therapy in patients with chronic hepatitis B. Severe exacerbation, sometimes developing into fulminant hepatic failure, is at high risk of mortality. The efficacy of corticosteroid therapy in "clinically severe" exacerbation of chronic hepatitis B has not been well demonstrated. In this study we evaluated the efficacy of early introduction of high-dose corticosteroid therapy in patients with lifethreatening severe exacerbation of chronic hepatitis B.METHODS: Twenty-two patients, 14 men and 8 women,were defined as "severe" exacerbation of chronic hepatitis B using uniform criteria and enrolled in this study. Eleven patients were treated with corticosteroids at 60 mg or more daily with or without anti-viral drugs within 10 d after the diagnosis of severe disease ("early high-dose"group) and 11 patients were either treated more than 10 d or untreated with corticosteroids ("non-early high-dose"group).RESULTS: Mean age, male-to-female ratio, mean prothrombin time (PT) activity, alanine transaminase (ALT)level, total bilirubin level, positivity of HBeAg, mean IgMHBc titer, and mean HBV DNA polymerase activity did not differ between the two groups. Ten of 11 patients of the "early high-dose" group survived, while only 2 of 11 patients of the "non-early high-dose" group survived (P<0.001). During the first 2 wk after the introduction of corticosteroids, improvements in PT activities and total bilirubin levels were observed in the "early high-dose"group. Both ALT levels and HBV DNA polymerase levels fell in both groups.CONCLUSION: The introduction of high-dose corticosteroid can reverse deterioration in patients with "clinically lifethreatening" severe exacerbation of chronic hepatitis B,when used in the early stage of illness.

  16. Robust multi-tissue gene panel for cancer detection

    Directory of Open Access Journals (Sweden)

    Talantov Dmitri

    2010-06-01

    . Apart from possible use in diagnosis of early tumorigenesis, some other potential uses of our methodology and gene panel would be in assisting pathologists in diagnosis of pre-cancerous lesions, determining tumor boundaries, assessing levels of contamination in cell populations in vitro and identifying transformations in cell cultures after multiple passages. Moreover, based on the robustness of this gene panel in identifying normal vs. tumor, mislabelled or misinterpreted samples can be pinpointed with high confidence.

  17. Robust estimation of hydrological model parameters

    Directory of Open Access Journals (Sweden)

    A. Bárdossy

    2008-11-01

    Full Text Available The estimation of hydrological model parameters is a challenging task. With increasing capacity of computational power several complex optimization algorithms have emerged, but none of the algorithms gives a unique and very best parameter vector. The parameters of fitted hydrological models depend upon the input data. The quality of input data cannot be assured as there may be measurement errors for both input and state variables. In this study a methodology has been developed to find a set of robust parameter vectors for a hydrological model. To see the effect of observational error on parameters, stochastically generated synthetic measurement errors were applied to observed discharge and temperature data. With this modified data, the model was calibrated and the effect of measurement errors on parameters was analysed. It was found that the measurement errors have a significant effect on the best performing parameter vector. The erroneous data led to very different optimal parameter vectors. To overcome this problem and to find a set of robust parameter vectors, a geometrical approach based on Tukey's half space depth was used. The depth of the set of N randomly generated parameters was calculated with respect to the set with the best model performance (Nash-Sutclife efficiency was used for this study for each parameter vector. Based on the depth of parameter vectors, one can find a set of robust parameter vectors. The results show that the parameters chosen according to the above criteria have low sensitivity and perform well when transfered to a different time period. The method is demonstrated on the upper Neckar catchment in Germany. The conceptual HBV model was used for this study.

  18. Robust expertise effects in right FFA.

    Science.gov (United States)

    McGugin, Rankin Williams; Newton, Allen T; Gore, John C; Gauthier, Isabel

    2014-10-01

    The fusiform face area (FFA) is one of several areas in occipito-temporal cortex whose activity is correlated with perceptual expertise for objects. Here, we investigate the robustness of expertise effects in FFA and other areas to a strong task manipulation that increases both perceptual and attentional demands. With high-resolution fMRI at 7T, we measured responses to images of cars, faces and a category globally visually similar to cars (sofas) in 26 subjects who varied in expertise with cars, in (a) a low load 1-back task with a single object category and (b) a high load task in which objects from two categories were rapidly alternated and attention was required to both categories. The low load condition revealed several areas more active as a function of expertise, including both posterior and anterior portions of FFA bilaterally (FFA1/FFA2, respectively). Under high load, fewer areas were positively correlated with expertise and several areas were even negatively correlated, but the expertise effect in face-selective voxels in the anterior portion of FFA (FFA2) remained robust. Finally, we found that behavioral car expertise also predicted increased responses to sofa images but no behavioral advantages in sofa discrimination, suggesting that global shape similarity to a category of expertise is enough to elicit a response in FFA and other areas sensitive to experience, even when the category itself is not of special interest. The robustness of expertise effects in right FFA2 and the expertise effects driven by visual similarity both argue against attention being the sole determinant of expertise effects in extrastriate areas.

  19. Robust transient dynamics and brain functions

    Directory of Open Access Journals (Sweden)

    Mikhail I Rabinovich

    2011-06-01

    Full Text Available In the last few decades several concepts of Dynamical Systems Theory (DST have guided psychologists, cognitive scientists, and neuroscientists to rethink about sensory motor behavior and embodied cognition. A critical step in the progress of DST application to the brain (supported by modern methods of brain imaging and multi-electrode recording techniques has been the transfer of its initial success in motor behavior to mental function, i.e., perception, emotion, and cognition. Open questions from research in genetics, ecology, brain sciences, etc. have changed DST itself and lead to the discovery of a new dynamical phenomenon, i.e., reproducible and robust transients that are at the same time sensitive to informational signals. The goal of this review is to describe a new mathematical framework -heteroclinic sequential dynamics- to understand self-organized activity in the brain that can explain certain aspects of robust itinerant behavior. Specifically, we discuss a hierarchy of coarse-grain models of mental dynamics in the form of kinetic equations of modes. These modes compete for resources at three levels: (i within the same modality, (ii among different modalities from the same family (like perception, and (iii among modalities from different families (like emotion and cognition. The analysis of the conditions for robustness, i.e., the structural stability of transient (sequential dynamics, give us the possibility to explain phenomena like the finite capacity of our sequential working memory -a vital cognitive function-, and to find specific dynamical signatures -different kinds of instabilities- of several brain functions and mental diseases.

  20. Robust Generalized Low Rank Approximations of Matrices.

    Directory of Open Access Journals (Sweden)

    Jiarong Shi

    Full Text Available In recent years, the intrinsic low rank structure of some datasets has been extensively exploited to reduce dimensionality, remove noise and complete the missing entries. As a well-known technique for dimensionality reduction and data compression, Generalized Low Rank Approximations of Matrices (GLRAM claims its superiority on computation time and compression ratio over the SVD. However, GLRAM is very sensitive to sparse large noise or outliers and its robust version does not have been explored or solved yet. To address this problem, this paper proposes a robust method for GLRAM, named Robust GLRAM (RGLRAM. We first formulate RGLRAM as an l1-norm optimization problem which minimizes the l1-norm of the approximation errors. Secondly, we apply the technique of Augmented Lagrange Multipliers (ALM to solve this l1-norm minimization problem and derive a corresponding iterative scheme. Then the weak convergence of the proposed algorithm is discussed under mild conditions. Next, we investigate a special case of RGLRAM and extend RGLRAM to a general tensor case. Finally, the extensive experiments on synthetic data show that it is possible for RGLRAM to exactly recover both the low rank and the sparse components while it may be difficult for previous state-of-the-art algorithms. We also discuss three issues on RGLRAM: the sensitivity to initialization, the generalization ability and the relationship between the running time and the size/number of matrices. Moreover, the experimental results on images of faces with large corruptions illustrate that RGLRAM obtains the best denoising and compression performance than other methods.

  1. Robust Generalized Low Rank Approximations of Matrices.

    Science.gov (United States)

    Shi, Jiarong; Yang, Wei; Zheng, Xiuyun

    2015-01-01

    In recent years, the intrinsic low rank structure of some datasets has been extensively exploited to reduce dimensionality, remove noise and complete the missing entries. As a well-known technique for dimensionality reduction and data compression, Generalized Low Rank Approximations of Matrices (GLRAM) claims its superiority on computation time and compression ratio over the SVD. However, GLRAM is very sensitive to sparse large noise or outliers and its robust version does not have been explored or solved yet. To address this problem, this paper proposes a robust method for GLRAM, named Robust GLRAM (RGLRAM). We first formulate RGLRAM as an l1-norm optimization problem which minimizes the l1-norm of the approximation errors. Secondly, we apply the technique of Augmented Lagrange Multipliers (ALM) to solve this l1-norm minimization problem and derive a corresponding iterative scheme. Then the weak convergence of the proposed algorithm is discussed under mild conditions. Next, we investigate a special case of RGLRAM and extend RGLRAM to a general tensor case. Finally, the extensive experiments on synthetic data show that it is possible for RGLRAM to exactly recover both the low rank and the sparse components while it may be difficult for previous state-of-the-art algorithms. We also discuss three issues on RGLRAM: the sensitivity to initialization, the generalization ability and the relationship between the running time and the size/number of matrices. Moreover, the experimental results on images of faces with large corruptions illustrate that RGLRAM obtains the best denoising and compression performance than other methods.

  2. Robust video hashing via multilinear subspace projections.

    Science.gov (United States)

    Li, Mu; Monga, Vishal

    2012-10-01

    The goal of video hashing is to design hash functions that summarize videos by short fingerprints or hashes. While traditional applications of video hashing lie in database searches and content authentication, the emergence of websites such as YouTube and DailyMotion poses a challenging problem of anti-piracy video search. That is, hashes or fingerprints of an original video (provided to YouTube by the content owner) must be matched against those uploaded to YouTube by users to identify instances of "illegal" or undesirable uploads. Because the uploaded videos invariably differ from the original in their digital representation (owing to incidental or malicious distortions), robust video hashes are desired. We model videos as order-3 tensors and use multilinear subspace projections, such as a reduced rank parallel factor analysis (PARAFAC) to construct video hashes. We observe that, unlike most standard descriptors of video content, tensor-based subspace projections can offer excellent robustness while effectively capturing the spatio-temporal essence of the video for discriminability. We introduce randomization in the hash function by dividing the video into (secret key based) pseudo-randomly selected overlapping sub-cubes to prevent against intentional guessing and forgery. Detection theoretic analysis of the proposed hash-based video identification is presented, where we derive analytical approximations for error probabilities. Remarkably, these theoretic error estimates closely mimic empirically observed error probability for our hash algorithm. Furthermore, experimental receiver operating characteristic (ROC) curves reveal that the proposed tensor-based video hash exhibits enhanced robustness against both spatial and temporal video distortions over state-of-the-art video hashing techniques.

  3. On robust forecasting of autoregressive time series under censoring

    OpenAIRE

    Kharin, Y.; Badziahin, I.

    2009-01-01

    Problems of robust statistical forecasting are considered for autoregressive time series observed under distortions generated by interval censoring. Three types of robust forecasting statistics are developed; meansquare risk is evaluated for the developed forecasting statistics. Numerical results are given.

  4. Robust Face Skin Selection for Unobtrusive Vital Signs Monitoring

    NARCIS (Netherlands)

    Ding, M.; Van Leest, A.J.

    2010-01-01

    In this report we developed an algorithm that robustly selects faceskin. The algorithm has been tested on a set of challenging sequences. It is robust to partial occlusions, rotation of the head and spectrum changes of the illumination.

  5. Two challenges in embedded systems design: predictability and robustness.

    Science.gov (United States)

    Henzinger, Thomas A

    2008-10-28

    I discuss two main challenges in embedded systems design: the challenge to build predictable systems, and that to build robust systems. I suggest how predictability can be formalized as a form of determinism, and robustness as a form of continuity.

  6. Robustness of mission plans for unmanned aircraft

    Science.gov (United States)

    Niendorf, Moritz

    This thesis studies the robustness of optimal mission plans for unmanned aircraft. Mission planning typically involves tactical planning and path planning. Tactical planning refers to task scheduling and in multi aircraft scenarios also includes establishing a communication topology. Path planning refers to computing a feasible and collision-free trajectory. For a prototypical mission planning problem, the traveling salesman problem on a weighted graph, the robustness of an optimal tour is analyzed with respect to changes to the edge costs. Specifically, the stability region of an optimal tour is obtained, i.e., the set of all edge cost perturbations for which that tour is optimal. The exact stability region of solutions to variants of the traveling salesman problems is obtained from a linear programming relaxation of an auxiliary problem. Edge cost tolerances and edge criticalities are derived from the stability region. For Euclidean traveling salesman problems, robustness with respect to perturbations to vertex locations is considered and safe radii and vertex criticalities are introduced. For weighted-sum multi-objective problems, stability regions with respect to changes in the objectives, weights, and simultaneous changes are given. Most critical weight perturbations are derived. Computing exact stability regions is intractable for large instances. Therefore, tractable approximations are desirable. The stability region of solutions to relaxations of the traveling salesman problem give under approximations and sets of tours give over approximations. The application of these results to the two-neighborhood and the minimum 1-tree relaxation are discussed. Bounds on edge cost tolerances and approximate criticalities are obtainable likewise. A minimum spanning tree is an optimal communication topology for minimizing the cumulative transmission power in multi aircraft missions. The stability region of a minimum spanning tree is given and tolerances, stability balls

  7. ROBUST CONTROL OF PERIODIC BIFURCATION SOLUTIONS

    Institute of Scientific and Technical Information of China (English)

    梁建术; 陈予恕; 梁以德

    2004-01-01

    The topological bifurcation diagrams and the coefficients of bifurcation equation were obtained by C-L method.According to obtained bifurcation diagrams and combining control theory,the method of robust control of periodic bifurcation was presented,which differs from generic methods of bifurcation control.It can make the existing motion pattern into the goal motion pattern.Because the method does not make strict requirement about parametric values of the controller,it is convenient to design and make it.Numerical simulations verify validity of the method.

  8. Robust regulation of anaerobic digestion processes.

    Science.gov (United States)

    Mailleret, L; Bernard, O; Steyer, J P

    2003-01-01

    This paper deals with the problem of controlling anaerobic digestion processes. A two-step (i.e. acidogenesis-methanization) mass balance model is considered for a 1 m3 fixed bed digester treating industrial wine distillery wastewater. The control law aims at regulating the organic pollution level while avoiding washout of biomass. To this end, a simple output feedback controller is considered which regulates a variable strongly related to the Chemical Oxygen Demand (COD). Numerical simulations assuming noisy measurements first illustrate the robustness of this control procedure. Then, the regulating procedure is implemented on the considered anaerobic digestion process in order to validate and demonstrate its efficiency in real life experiments.

  9. Robust Pseudo-Hierarchical Support Vector Clustering

    DEFF Research Database (Denmark)

    Hansen, Michael Sass; Sjöstrand, Karl; Olafsdóttir, Hildur

    2007-01-01

    Support vector clustering (SVC) has proven an efficient algorithm for clustering of noisy and high-dimensional data sets, with applications within many fields of research. An inherent problem, however, has been setting the parameters of the SVC algorithm. Using the recent emergence of a method...... for calculating the entire regularization path of the support vector domain description, we propose a fast method for robust pseudo-hierarchical support vector clustering (HSVC). The method is demonstrated to work well on generated data, as well as for detecting ischemic segments from multidimensional myocardial...

  10. Adding Query Privacy to Robust DHTs

    DEFF Research Database (Denmark)

    Backes, Michael; Goldberg, Ian; Kate, Aniket

    2011-01-01

    of obtaining query privacy over robust DHTs. Finally, we compare the performance of our privacy-preserving protocols with their more privacy-invasive counterparts. We observe that there is no increase in the message complexity and only a small overhead in the computational complexity....... intermediate peers that (help to) route the queries towards their destinations. In this paper, we satisfy this requirement by presenting an approach for providing privacy for the keys in DHT queries. We use the concept of oblivious transfer (OT) in communication over DHTs to preserve query privacy without...

  11. A Robust Algorithm in Active Queue Management

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A variable structure based control scheme was proposed for Active Queue Management (AQM) by using sliding model algorithm and reach law method. This approach aims toaddress the tradeoff between good performance and robustness with respect to the uncertainties of the round-trip time and the number of active connections. Ns simulations results show that the proposed design significantly outperforms the peer AQM schemes in terms of fluctuation in the queue length, packet throughput, and loss ratio. The conclusion is that proposed scheme is in favor of the achievement to AQM objectives due to its good transient and steady performance.

  12. BOOSTING CED USING ROBUST ORIENTATION ESTIMATION

    Directory of Open Access Journals (Sweden)

    Tariq M. Khan

    2014-05-01

    Full Text Available In this paper, Coherence Enhancement Diffusion (CED is boosted feeding external orientation using new robust orientation estimation. In CED, proper scale selection is very important as the gradient vector at that scale reflects the orientation of local ridge. For this purpose a new scheme is proposed in which pre calculated orientation, by using local and integration scales. From the experiments it is found the proposed scheme is working much better in noisy environment as compared to the traditional Coherence Enhancement Diffusion

  13. Mobility Robustness in 5G Networks

    OpenAIRE

    2016-01-01

    5G is the 5th Generation of Mobile telecommunication system. 5G networks will cater to the needs of very diverse user equipment, from millions of stationary sensors per square kilometer to bullet trains running at over 500 km/h. Presence of users with such varied mobility requirements entails us to build a robust mobility architecture for 5G. Two of the important requirements for 5G networks are a lower latency and a higher reliability than in existing generations of mobile networks. To a...

  14. Robust LQR Control Design of Gyroscope

    Directory of Open Access Journals (Sweden)

    Ashok S. Chandak

    2013-04-01

    Full Text Available The basic problem in designing control systems isthe ability to achieve good performance inthepresenceofuncertainties such as outputdisturbances, measurement noise or unmodeleddynamics (i.e. robust controllers. Recentdevelopment in the area has been directed towardsdeveloping a consistent design methodology withinthis uncertain environment. The attitude control/momentum management of the space station posesatypical problem in ahighlyuncertain environment(such asmass properties of the Space Station andenvironmental disturbancesas well as parametricuncertainties. The objective of this research is touse LQR control for the position control of spin axisrotor position at reference value in the presence ofparametric uncertainties, external unmeasurabledisturbances and system inherent non-linearitywithdifferenttype’sreference tracking signal areconsidered extensively in this paper.

  15. Robust utility maximization in a discontinuous filtration

    CERN Document Server

    Jeanblanc, Monique; Ngoupeyou, Armand

    2012-01-01

    We study a problem of utility maximization under model uncertainty with information including jumps. We prove first that the value process of the robust stochastic control problem is described by the solution of a quadratic-exponential backward stochastic differential equation with jumps. Then, we establish a dynamic maximum principle for the optimal control of the maximization problem. The characterization of the optimal model and the optimal control (consumption-investment) is given via a forward-backward system which generalizes the result of Duffie and Skiadas (1994) and El Karoui, Peng and Quenez (2001) in the case of maximization of recursive utilities including model with jumps.

  16. Robust force control of a robot manipulator

    Energy Technology Data Exchange (ETDEWEB)

    Dawson, D.M. (Clemson Univ., SC (United States)); Lewis, F.L. (Univ. of Texas, Fort Worth (United States)); Dorsey, J.F. (Georgia Inst. of Tech., Atlanta (United States))

    1992-08-01

    In this article, the authors develop a robust position/force controller based on the impedance approach without requiring exact knowledge of the robot dynamics. The controller is constructed so that a desired positional trajectory can be followed along the surface of the environment while the forces exerted on the environmental surface are regulated according to a target impedance. A global uniform ultimate boundedness result is obtained for the position tracking error and the force regulation error (i.e., the error between the actual manipulator impedance and desired target impedance). The controller only requires measurement of the end-effector force, joint velocity, and joint position.

  17. Robust indexing for automatic data collection

    Energy Technology Data Exchange (ETDEWEB)

    Sauter, Nicholas K.; Grosse-Kunstleve, Ralf W.; Adams, Paul D.

    2003-12-09

    We present improved methods for indexing diffraction patterns from macromolecular crystals. The novel procedures include a more robust way to verify the position of the incident X-ray beam on the detector, an algorithm to verify that the deduced lattice basis is consistent with the observations, and an alternative approach to identify the metric symmetry of the lattice. These methods help to correct failures commonly experienced during indexing, and increase the overall success rate of the process. Rapid indexing, without the need for visual inspection, will play an important role as beamlines at synchrotron sources prepare for high-throughput automation.

  18. Reconfigurable Robust Routing for Mobile Outreach Network

    Science.gov (United States)

    Lin, Ching-Fang

    2010-01-01

    The Reconfigurable Robust Routing for Mobile Outreach Network (R3MOO N) provides advanced communications networking technologies suitable for the lunar surface environment and applications. The R3MOON techn ology is based on a detailed concept of operations tailored for luna r surface networks, and includes intelligent routing algorithms and wireless mesh network implementation on AGNC's Coremicro Robots. The product's features include an integrated communication solution inco rporating energy efficiency and disruption-tolerance in a mobile ad h oc network, and a real-time control module to provide researchers an d engineers a convenient tool for reconfiguration, investigation, an d management.

  19. Charlemagne was very tall, but not robust.

    Science.gov (United States)

    Rühli, Frank J; Blümich, Bernhard; Henneberg, Maciej

    2010-07-01

    The left tibia of Charlemagne, the Medieval "Father of Europe" has been X-rayed and CT scanned to determine his still highly debated stature. We found the healthy bone to be long (430 mm) but rather not robust (total mid-shaft cross-sectional area 473 mm(2), cortical area 352 mm(2)). Reconstructed stature of 1.84 m falls at about 99% of Medieval heights, which would be ca. 1.95 m in present-day Europe. Thus, tall stature indeed could have contributed to the success of "Charles the Great" as a king emperor and soldier.

  20. Robust topology optimization accounting for geometric imperfections

    DEFF Research Database (Denmark)

    Schevenels, M.; Jansen, M.; Lombaert, Geert

    2013-01-01

    performance. As a consequence, the actual structure may be far from optimal. In this paper, a robust approach to topology optimization is presented, taking into account two types of geometric imperfections: variations of (1) the crosssections and (2) the locations of structural elements. The first type...... is modeled by means of a scalar non-Gaussian random field, which is represented as a translation process. The underlying Gaussian field is simulated by means of the EOLE method. The second type of imperfections is modeled as a Gaussian vector-valued random field, which is simulated directly by means...

  1. Robust, directed assembly of fluorescent nanodiamonds.

    Science.gov (United States)

    Kianinia, Mehran; Shimoni, Olga; Bendavid, Avi; Schell, Andreas W; Randolph, Steven J; Toth, Milos; Aharonovich, Igor; Lobo, Charlene J

    2016-10-27

    Arrays of fluorescent nanoparticles are highly sought after for applications in sensing, nanophotonics and quantum communications. Here we present a simple and robust method of assembling fluorescent nanodiamonds into macroscopic arrays. Remarkably, the yield of this directed assembly process is greater than 90% and the assembled patterns withstand ultra-sonication for more than three hours. The assembly process is based on covalent bonding of carboxyl to amine functional carbon seeds and is applicable to any material, and to non-planar surfaces. Our results pave the way to directed assembly of sensors and nanophotonics devices.

  2. Exact solution of the robust knapsack problem☆

    Science.gov (United States)

    Monaci, Michele; Pferschy, Ulrich; Serafini, Paolo

    2013-01-01

    We consider an uncertain variant of the knapsack problem in which the weight of the items is not exactly known in advance, but belongs to a given interval, and an upper bound is imposed on the number of items whose weight differs from the expected one. For this problem, we provide a dynamic programming algorithm and present techniques aimed at reducing its space and time complexities. Finally, we computationally compare the performances of the proposed algorithm with those of different exact algorithms presented so far in the literature for robust optimization problems. PMID:24187428

  3. Robust, directed assembly of fluorescent nanodiamonds

    CERN Document Server

    Kianinia, Mehran; Shimoni, Olga; Randolph, Steven J; Toth, Milos; Aharonovich, Igor; Lobo, Charlene J

    2016-01-01

    Arrays of fluorescent nanoparticles are highly sought after for applications in sensing and nanophotonics. Here we present a simple and robust method of assembling fluorescent nanodiamonds into macroscopic arrays. Remarkably, the yield of this directed assembly process is greater than 90% and the assembled patterns withstand ultra-sonication for more than three hours. The assembly process is based on covalent bonding of carboxyl to amine functional carbon seeds and is applicable to any material, and to non-planar surfaces. Our results pave the way to directed assembly of sensing and nanophotonics devices.

  4. Reliability and Robustness Evaluation of Timber Structures

    DEFF Research Database (Denmark)

    Cizmar, Dean; Sørensen, John Dalsgaard; Kirkegaard, Poul Henning

    In the last few decades there have been intensely research concerning reliability of timber structures. This is primarily because there is an increased focus on society on sustainability and environmental aspects. Modern timber as a building material is also being competitive compared to concrete...... parameters is given. System models (series and parallel) are discused and methods for reliability calculation are given. Special attention is drawn upon brittle/ductile modelling of timber and connections. In chapter 2 robustness requirements implemended in codes are presented. State of the art definitions...

  5. Robust Bioinformatics Recognition with VLSI Biochip Microsystem

    Science.gov (United States)

    Lue, Jaw-Chyng L.; Fang, Wai-Chi

    2006-01-01

    A microsystem architecture for real-time, on-site, robust bioinformatic patterns recognition and analysis has been proposed. This system is compatible with on-chip DNA analysis means such as polymerase chain reaction (PCR)amplification. A corresponding novel artificial neural network (ANN) learning algorithm using new sigmoid-logarithmic transfer function based on error backpropagation (EBP) algorithm is invented. Our results show the trained new ANN can recognize low fluorescence patterns better than the conventional sigmoidal ANN does. A differential logarithmic imaging chip is designed for calculating logarithm of relative intensities of fluorescence signals. The single-rail logarithmic circuit and a prototype ANN chip are designed, fabricated and characterized.

  6. Robust surface roughness indices and morphological interpretation

    Science.gov (United States)

    Trevisani, Sebastiano; Rocca, Michele

    2016-04-01

    Geostatistical-based image/surface texture indices based on variogram (Atkison and Lewis, 2000; Herzfeld and Higginson, 1996; Trevisani et al., 2012) and on its robust variant MAD (median absolute differences, Trevisani and Rocca, 2015) offer powerful tools for the analysis and interpretation of surface morphology (potentially not limited to solid earth). In particular, the proposed robust index (Trevisani and Rocca, 2015) with its implementation based on local kernels permits the derivation of a wide set of robust and customizable geomorphometric indices capable to outline specific aspects of surface texture. The stability of MAD in presence of signal noise and abrupt changes in spatial variability is well suited for the analysis of high-resolution digital terrain models. Moreover, the implementation of MAD by means of a pixel-centered perspective based on local kernels, with some analogies to the local binary pattern approach (Lucieer and Stein, 2005; Ojala et al., 2002), permits to create custom roughness indices capable to outline different aspects of surface roughness (Grohmann et al., 2011; Smith, 2015). In the proposed poster, some potentialities of the new indices in the context of geomorphometry and landscape analysis will be presented. At same time, challenges and future developments related to the proposed indices will be outlined. Atkinson, P.M., Lewis, P., 2000. Geostatistical classification for remote sensing: an introduction. Computers & Geosciences 26, 361-371. Grohmann, C.H., Smith, M.J., Riccomini, C., 2011. Multiscale Analysis of Topographic Surface Roughness in the Midland Valley, Scotland. IEEE Transactions on Geoscience and Remote Sensing 49, 1220-1213. Herzfeld, U.C., Higginson, C.A., 1996. Automated geostatistical seafloor classification - Principles, parameters, feature vectors, and discrimination criteria. Computers and Geosciences, 22 (1), pp. 35-52. Lucieer, A., Stein, A., 2005. Texture-based landform segmentation of LiDAR imagery

  7. PID control with robust disturbance feedback control

    DEFF Research Database (Denmark)

    Kawai, Fukiko; Vinther, Kasper; Andersen, Palle

    2015-01-01

    Disturbance Feedback Control (DFC) is a technique, originally proposed by Fuji Electric, for augmenting existing control systems with an extra feedback for attenuation of disturbances and model errors. In this work, we analyze the robustness and performance of a PID-based control system with DFC...... and performance (if such gains exist). Finally, two different simulation case studies are evaluated and compared. Our numerical studies indicate that better performance can be achieved with the proposed method compared with a conservatively tuned PID controller and comparable performance can be achieved when...... compared with an H-infinity controller....

  8. Robustizing Circuit Optimization using Huber Functions

    DEFF Research Database (Denmark)

    Bandler, John W.; Biernacki, Radek M.; Chen, Steve H.;

    1993-01-01

    The authors introduce a novel approach to 'robustizing' microwave circuit optimization using Huber functions, both two-sided and one-sided. They compare Huber optimization with l/sub 1/, l/sub 2/, and minimax methods in the presence of faults, large and small measurement errors, bad starting points......, and statistical uncertainties. They demonstrate FET statistical modeling, multiplexer optimization, analog fault location, and data fitting. They extend the Huber concept by introducing a 'one-sided' Huber function for large-scale optimization. For large-scale problems, the designer often attempts, by intuition...

  9. Huber Optimization of Circuits: A Robust Approach

    DEFF Research Database (Denmark)

    Bandler, J. W.; Biernacki, R.; Chen, S.;

    1993-01-01

    The authors introduce an approach to robust circuit optimization using Huber functions, both two-sided and one-sided. They compare Huber optimization with l/sub 1/, l/sub 2/, and minimax methods in the presence of faults, large and small measurement errors, bad starting points, and statistical...... uncertainties. They demonstrate FET statistical modeling, multiplexer optimization, analog fault location, and data fitting. They extend the Huber concept by introducing a one-sided Huber function for large-scale optimization. For large-scale problems, the designer often attempts, by intuition, a preliminary...

  10. Robustness of the Blandford-Znajek mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Palenzuela, Carlos [Canadian Institute for Theoretical Astrophysics, Toronto, Ontario M5S 3H8 (Canada); Bona, Carles [Institute for Applied Computing with Community Code (IAC3), Universitat de les Illes Balears, Palma de Mallorca 07122 (Spain); Lehner, Luis; Reula, Oscar, E-mail: palen@cita.utoronto.ca [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70802 (United States)

    2011-07-07

    The Blandford-Znajek (BZ) mechanism has long been regarded as a key ingredient in models attempting to explain powerful jets in AGNs, quasars, blazzars, etc. In such a mechanism, energy is extracted from a rotating black hole and dissipated at a load at far distances. In this work we examine the behavior of the BZ mechanism with respect to different boundary conditions, revealing the robustness of the mechanism upon variation of these conditions. Consequently, this work closes a gap in our understanding of this important scenario.

  11. Robust SPIHT-based Image Compression

    Institute of Scientific and Technical Information of China (English)

    CHENHailin; YANGYuhang

    2003-01-01

    As a famous wavelet-based image coding technique, Set partitioning in hierarchical trees (SPIHT) provides excellent rate distortion performance and progressive display properties when images are transmitted over lossless networks. But due to its highly statedependent properties, it performs poorly over losing networks. In this paper, we propose an algorithm to reorganize the wavelet transform coefficients according to wavelet tree concept and code each wavelet tree independently. Then, each coded bit-plane of each wavelet tree is packetized and transmitted to networks independently with little header information. Experimental results show that the proposed algorithm improves the robustness of the bit steam greatly while preserving its progressive display properties.

  12. Robust and resistant 2D shape alignment

    DEFF Research Database (Denmark)

    Larsen, Rasmus; Eiriksson, Hrafnkell

    2001-01-01

    \\_\\$\\backslash\\$infty\\$ norm alignments are formulated as linear programming problems. The linear vector function formulation along with the different norms results in alignment methods that are both resistant from influence from outliers, robust wrt. errors in the annotation and capable of handling missing datapoints......We express the alignment of 2D shapes as the minimization of the norm of a linear vector function. The minimization is done in the \\$l\\_1\\$, \\$l\\_2\\$ and the \\$l\\_\\$\\backslash\\$infty\\$ norms using well known standard numerical methods. In particular, the \\$l\\_1\\$ and the \\$l...

  13. Cooperation on Social Networks and Its Robustness

    CERN Document Server

    Antonioni, Alberto

    2012-01-01

    In this work we have used computer models of social-like networks to show by extensive numerical simulations that cooperation in evolutionary games can emerge and be stable on this class of networks. The amounts of cooperation reached are at least as much as in scale-free networks but here the population model is more realistic. Cooperation is robust with respect to different strategy update rules, population dynamics, and payoff computation. Only when straight average payoff is used or there is high strategy or network noise does cooperation decrease in all games and disappear in the Prisoner's Dilemma.

  14. On the robustness of random Boolean formulae

    Energy Technology Data Exchange (ETDEWEB)

    Mozeika, Alexander; Saad, David [Non-linearity and Complexity Research Group, Aston University, Birmingham B4 7ET (United Kingdom); Raymond, Jack, E-mail: a.s.mozeika@aston.ac.u, E-mail: d.saad@aston.ac.u [Department of Physics, Hong Kong University of Science and Technology, Clear Water Bay (Hong Kong)

    2010-06-01

    Random Boolean formulae, generated by a growth process of noisy logical gates are analyzed using the generating functional methodology of statistical physics. We study the type of functions generated for different input distributions, their robustness for a given level of gate error and its dependence on the formulae depth and complexity and the gates used. Bounds on their performance, derived in the information theory literature for specific gates, are straightforwardly retrieved, generalized and identified as the corresponding typical-case phase transitions. Results for error-rates, function-depth and sensitivity of the generated functions are obtained for various gate-type and noise models.

  15. Hybrid Dynamical Systems Modeling, Stability, and Robustness

    CERN Document Server

    Goebel, Rafal; Teel, Andrew R

    2012-01-01

    Hybrid dynamical systems exhibit continuous and instantaneous changes, having features of continuous-time and discrete-time dynamical systems. Filled with a wealth of examples to illustrate concepts, this book presents a complete theory of robust asymptotic stability for hybrid dynamical systems that is applicable to the design of hybrid control algorithms--algorithms that feature logic, timers, or combinations of digital and analog components. With the tools of modern mathematical analysis, Hybrid Dynamical Systems unifies and generalizes earlier developments in continuous-time and discret

  16. Automatic Synthesis of Robust and Optimal Controllers

    DEFF Research Database (Denmark)

    Cassez, Franck; Jessen, Jan Jacob; Larsen, Kim Guldstrand;

    2009-01-01

    In this paper, we show how to apply recent tools for the automatic synthesis of robust and near-optimal controllers for a real industrial case study. We show how to use three different classes of models and their supporting existing tools, Uppaal-TiGA for synthesis, phaver for verification......, and Simulink for simulation, in a complementary way. We believe that this case study shows that our tools have reached a level of maturity that allows us to tackle interesting and relevant industrial control problems....

  17. Robust Design of Sounds in Mechanical Mechanisms

    DEFF Research Database (Denmark)

    Boegedal Jensen, Annemette; Munch, Natasja; Howard, Thomas J.;

    2015-01-01

    Current practices for creating a desired sound by a mechanical mechanism are irrelative design-build-test processes. It seems that very little guidance is available relating design to the sound output. The focus of this study was to identify, which parameters that affect the sound output of a click...... mechanism consisting of a toothed rack and a click arm. First several geometries of the teeth and the click arm’s head were investigated to identify the most robust and repeatable design. It was found that a flat surface in the valleys between the teeth is very beneficial in relation to repeatability...... mechanisms....

  18. Grassmann Averages for Scalable Robust PCA

    OpenAIRE

    2014-01-01

    As the collection of large datasets becomes increasingly automated, the occurrence of outliers will increase—“big data” implies “big outliers”. While principal component analysis (PCA) is often used to reduce the size of data, and scalable solutions exist, it is well-known that outliers can arbitrarily corrupt the results. Unfortunately, state-of-the-art approaches for robust PCA do not scale beyond small-to-medium sized datasets. To address this, we introduce the Grassmann Average (GA), whic...

  19. A Conceptual Methodology for Assessing Acquisition Requirements Robustness against Technology Uncertainties

    Science.gov (United States)

    Chou, Shuo-Ju

    2011-12-01

    In recent years the United States has shifted from a threat-based acquisition policy that developed systems for countering specific threats to a capabilities-based strategy that emphasizes the acquisition of systems that provide critical national defense capabilities. This shift in policy, in theory, allows for the creation of an "optimal force" that is robust against current and future threats regardless of the tactics and scenario involved. In broad terms, robustness can be defined as the insensitivity of an outcome to "noise" or non-controlled variables. Within this context, the outcome is the successful achievement of defense strategies and the noise variables are tactics and scenarios that will be associated with current and future enemies. Unfortunately, a lack of system capability, budget, and schedule robustness against technology performance and development uncertainties has led to major setbacks in recent acquisition programs. This lack of robustness stems from the fact that immature technologies have uncertainties in their expected performance, development cost, and schedule that cause to variations in system effectiveness and program development budget and schedule requirements. Unfortunately, the Technology Readiness Assessment process currently used by acquisition program managers and decision-makers to measure technology uncertainty during critical program decision junctions does not adequately capture the impact of technology performance and development uncertainty on program capability and development metrics. The Technology Readiness Level metric employed by the TRA to describe program technology elements uncertainties can only provide a qualitative and non-descript estimation of the technology uncertainties. In order to assess program robustness, specifically requirements robustness, against technology performance and development uncertainties, a new process is needed. This process should provide acquisition program managers and decision

  20. Precise ablation of dental hard tissues with ultra-short pulsed lasers. Preliminary exploratory investigation on adequate laser parameters.

    Science.gov (United States)

    Bello-Silva, Marina Stella; Wehner, Martin; Eduardo, Carlos de Paula; Lampert, Friedrich; Poprawe, Reinhart; Hermans, Martin; Esteves-Oliveira, Marcella

    2013-01-01

    This study aimed to evaluate the possibility of introducing ultra-short pulsed lasers (USPL) in restorative dentistry by maintaining the well-known benefits of lasers for caries removal, but also overcoming disadvantages, such as thermal damage of irradiated substrate. USPL ablation of dental hard tissues was investigated in two phases. Phase 1--different wavelengths (355, 532, 1,045, and 1,064 nm), pulse durations (picoseconds and femtoseconds) and irradiation parameters (scanning speed, output power, and pulse repetition rate) were assessed for enamel and dentin. Ablation rate was determined, and the temperature increase measured in real time. Phase 2--the most favorable laser parameters were evaluated to correlate temperature increase to ablation rate and ablation efficiency. The influence of cooling methods (air, air-water spray) on ablation process was further analyzed. All parameters tested provided precise and selective tissue ablation. For all lasers, faster scanning speeds resulted in better interaction and reduced temperature increase. The most adequate results were observed for the 1064-nm ps-laser and the 1045-nm fs-laser. Forced cooling caused moderate changes in temperature increase, but reduced ablation, being considered unnecessary during irradiation with USPL. For dentin, the correlation between temperature increase and ablation efficiency was satisfactory for both pulse durations, while for enamel, the best correlation was observed for fs-laser, independently of the power used. USPL may be suitable for cavity preparation in dentin and enamel, since effective ablation and low temperature increase were observed. If adequate laser parameters are selected, this technique seems to be promising for promoting the laser-assisted, minimally invasive approach.