THE SWIFT BAT SURVEY DETECTS TWO OPTICAL BROAD LINE, X-RAY HEAVILY OBSCURED ACTIVE GALAXIES: NVSS 193013+341047 AND IRAS 05218-1212

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

Hogg, J. Drew; Winter, Lisa M.; Mushotzky, Richard F.

2012-06-20

The Swift Burst Alert Telescope (BAT) is discovering interesting new objects while monitoring the sky in the 14-195 keV band. Here we present the X-ray properties and spectral energy distributions (SEDs) for two unusual active galactic nucleus sources. Both NVSS 193013+341047 and IRAS 05218-1212 are absorbed, Compton-thin, but heavily obscured (N{sub H} {approx} 10{sup 23} cm{sup -2}), X-ray sources at redshifts <0.1. The SEDs reveal these galaxies to be very red, with high extinction in the optical and UV. A similar SED is seen for the extremely red objects (EROs) detected in the higher redshift universe. This suggests that thesemore » unusual BAT-detected sources are a low-redshift (z << 1) analog to EROs, which recent evidence suggests are a class of the elusive type II quasars. Studying the multi-wavelength properties of these sources may reveal the properties of their high-redshift counterparts.« less

VizieR Online Data Catalog: Extragalactic peaked-spectrum radio sources (Callingham+, 2017)

NASA Astrophysics Data System (ADS)

Callingham, J. R.; Ekers, R. D.; Gaensler, B. M.; Line, J. L. B.; Hurley-Walker, N.; Sadler, E. M.; Tingay, S. J.; Hancock, P. J.; Bell, M. E.; Dwarakanath, K. S.; For, B.-Q.; Franzen, T. M. O.; Hindson, L.; Johnston-Hollitt, M.; Kapinska, A. D.; Lenc, E.; McKinley, B.; Morgan, J.; Offringa, A. R.; Procopio, P.; Staveley-Smith, L.; Wayth, R. B.; Wu, C.; Zheng, Q.

2017-09-01

The GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) extragalactic catalog represents a significant advance in selecting peaked-spectrum sources, since it is constituted of sources that were contemporaneously surveyed with the widest fractional radio bandwidth to date, with 20 flux density measurements between 72 and 231MHz. We also use the NRAO VLA Sky Survey (NVSS; Condon+ 1998, VIII/65) and the Sydney University Molonglo Sky Survey (SUMSS; See Mauch+ 2008, VIII/81). Since the combination of NVSS and SUMSS cover the entire GLEAM survey and are an order of magnitude more sensitive, this study is sensitive to peaked-spectrum sources that peak anywhere between 72MHz and 843MHz/1.4GHz. The GLEAM survey was formed from observations conducted by the Murchison Widefield Array (MWA), which surveyed the sky between 72 and 231MHz from 2013 August to 2014 July (Wayth+ 2015PASA...32...25W - see also VIII/100). (5 data files).

Illicit Drug Use, Illicit Drug Use Disorders, and Drug Overdose Deaths in Metropolitan and Nonmetropolitan Areas — United States

PubMed Central

Jones, Christopher M.; Ballesteros, Michael F.

2017-01-01

Problem/Condition Drug overdoses are a leading cause of injury death in the United States, resulting in approximately 52,000 deaths in 2015. Understanding differences in illicit drug use, illicit drug use disorders, and overall drug overdose deaths in metropolitan and nonmetropolitan areas is important for informing public health programs, interventions, and policies. Reporting Period Illicit drug use and drug use disorders during 2003–2014, and drug overdose deaths during 1999–2015. Description of Data The National Survey of Drug Use and Health (NSDUH) collects information through face-to-face household interviews about the use of illicit drugs, alcohol, and tobacco among the U.S. noninstitutionalized civilian population aged ≥12 years. Respondents include residents of households and noninstitutional group quarters (e.g., shelters, rooming houses, dormitories, migratory workers’ camps, and halfway houses) and civilians living on military bases. NSDUH variables include sex, age, race/ethnicity, residence (metropolitan/nonmetropolitan), annual household income, self-reported drug use, and drug use disorders. National Vital Statistics System Mortality (NVSS-M) data for U.S. residents include information from death certificates filed in the 50 states and the District of Columbia. Cases were selected with an underlying cause of death based on the ICD-10 codes for drug overdoses (X40–X44, X60–X64, X85, and Y10–Y14). NVSS-M variables include decedent characteristics (sex, age, and race/ethnicity) and information on intent (unintentional, suicide, homicide, or undetermined), location of death (medical facility, in a home, or other [including nursing homes, hospices, unknown, and other locations]) and county of residence (metropolitan/nonmetropolitan). Metropolitan/nonmetropolitan status is assigned independently in each data system. NSDUH uses a three-category system: Core Based Statistical Area (CBSA) of ≥1 million persons; CBSA of <1 million persons; and not a CBSA, which for simplicity were labeled large metropolitan, small metropolitan, and nonmetropolitan. Deaths from NVSS-M are categorized by the county of residence of the decedent using CDC’s National Center for Health Statistics 2013 Urban-Rural Classification Scheme, collapsed into two categories (metropolitan and nonmetropolitan). Results Although both metropolitan and nonmetropolitan areas experienced significant increases from 2003–2005 to 2012–2014 in self-reported past-month use of illicit drugs, the prevalence was highest for the large metropolitan areas compared with small metropolitan or nonmetropolitan areas throughout the study period. Notably, past-month use of illicit drugs declined over the study period for the youngest respondents (aged 12–17 years). The prevalence of past-year illicit drug use disorders among persons using illicit drugs in the past year varied by metropolitan/nonmetropolitan status and changed over time. Across both metropolitan and nonmetropolitan areas, the prevalence of past-year illicit drug use disorders declined during 2003–2014. In 2015, approximately six times as many drug overdose deaths occurred in metropolitan areas than occurred in nonmetropolitan areas (metropolitan: 45,059; nonmetropolitan: 7,345). Drug overdose death rates (per 100,000 population) for metropolitan areas were higher than in nonmetropolitan areas in 1999 (6.4 versus 4.0), however, the rates converged in 2004, and by 2015, the nonmetropolitan rate (17.0) was slightly higher than the metropolitan rate (16.2). Interpretation Drug use and subsequent overdoses continue to be a critical and complicated public health challenge across metropolitan/nonmetropolitan areas. The decline in illicit drug use by youth and the lower prevalence of illicit drug use disorders in rural areas during 2012–2014 are encouraging signs. However, the increasing rate of drug overdose deaths in rural areas, which surpassed rates in urban areas, is cause for concern. Public Health Actions Understanding the differences between metropolitan and nonmetropolitan areas in drug use, drug use disorders, and drug overdose deaths can help public health professionals to identify, monitor, and prioritize responses. Consideration of where persons live and where they die from overdose could enhance specific overdose prevention interventions, such as training on naloxone administration or rescue breathing. Educating prescribers on CDC’s guideline for prescribing opioids for chronic pain (Dowell D, Haegerich TM, Chou R. CDC guideline for prescribing opioids for chronic pain—United States, 2016. MMWR Recomm Rep 2016;66[No. RR-1]) and facilitating better access to medication-assisted treatment with methadone, buprenorphine, or naltrexone could benefit communities with high opioid use disorder rates. PMID:29049278

Illicit Drug Use, Illicit Drug Use Disorders, and Drug Overdose Deaths in Metropolitan and Nonmetropolitan Areas-United States.

PubMed

Mack, Karin A; Jones, Christopher M; Ballesteros, Michael F

2017-12-01

Drug overdoses are a leading cause of injury death in the United States, resulting in approximately 52,000 deaths in 2015. Understanding differences in illicit drug use, illicit drug use disorders, and overall drug overdose deaths in metropolitan and nonmetropolitan areas is important for informing public health programs, interventions, and policies. Illicit drug use and drug use disorders during 2003-2014, and drug overdose deaths during 1999-2015. The National Survey of Drug Use and Health (NSDUH) collects information through face-to-face household interviews about the use of illicit drugs, alcohol, and tobacco among the U.S. noninstitutionalized civilian population aged ≥12 years. Respondents include residents of households and noninstitutional group quarters (e.g., shelters, rooming houses, dormitories, migratory workers' camps, and halfway houses) and civilians living on military bases. NSDUH variables include sex, age, race/ethnicity, residence (metropolitan/nonmetropolitan), annual household income, self-reported drug use, and drug use disorders. National Vital Statistics System Mortality (NVSS-M) data for U.S. residents include information from death certificates filed in the 50 states and the District of Columbia. Cases were selected with an underlying cause of death based on the ICD-10 codes for drug overdoses (X40-X44, X60-X64, X85, and Y10-Y14). NVSS-M variables include decedent characteristics (sex, age, and race/ethnicity) and information on intent (unintentional, suicide, homicide, or undetermined), location of death (medical facility, in a home, or other [including nursing homes, hospices, unknown, and other locations]) and county of residence (metropolitan/nonmetropolitan). Metropolitan/nonmetropolitan status is assigned independently in each data system. NSDUH uses a three-category system: Core Based Statistical Area (CBSA) of ≥1 million persons; CBSA of <1 million persons; and not a CBSA, which for simplicity were labeled large metropolitan, small metropolitan, and nonmetropolitan. Deaths from NVSS-M are categorized by the county of residence of the decedent using CDC's National Center for Health Statistics 2013 Urban-Rural Classification Scheme, collapsed into two categories (metropolitan and nonmetropolitan). Although both metropolitan and nonmetropolitan areas experienced significant increases from 2003-2005 to 2012-2014 in self-reported past-month use of illicit drugs, the prevalence was highest for the large metropolitan areas compared with small metropolitan or nonmetropolitan areas throughout the study period. Notably, past-month use of illicit drugs declined over the study period for the youngest respondents (aged 12-17 years). The prevalence of past-year illicit drug use disorders among persons using illicit drugs in the past year varied by metropolitan/nonmetropolitan status and changed over time. Across both metropolitan and nonmetropolitan areas, the prevalence of past-year illicit drug use disorders declined during 2003-2014. In 2015, approximately six times as many drug overdose deaths occurred in metropolitan areas than occurred in nonmetropolitan areas (metropolitan: 45,059; nonmetropolitan: 7,345). Drug overdose death rates (per 100,000 population) for metropolitan areas were higher than in nonmetropolitan areas in 1999 (6.4 versus 4.0), however, the rates converged in 2004, and by 2015, the nonmetropolitan rate (17.0) was slightly higher than the metropolitan rate (16.2). Drug use and subsequent overdoses continue to be a critical and complicated public health challenge across metropolitan/nonmetropolitan areas. The decline in illicit drug use by youth and the lower prevalence of illicit drug use disorders in rural areas during 2012-2014 are encouraging signs. However, the increasing rate of drug overdose deaths in rural areas, which surpassed rates in urban areas, is cause for concern. Understanding the differences between metropolitan and nonmetropolitan areas in drug use, drug use disorders, and drug overdose deaths can help public health professionals to identify, monitor, and prioritize responses. Consideration of where persons live and where they die from overdose could enhance specific overdose prevention interventions, such as training on naloxone administration or rescue breathing. Educating prescribers on CDC's guideline for prescribing opioids for chronic pain (Dowell D, Haegerich TM, Chou R. CDC guideline for prescribing opioids for chronic pain-United States, 2016. MMWR Recomm Rep 2016;66[No. RR-1]) and facilitating better access to medication-assisted treatment with methadone, buprenorphine, or naltrexone could benefit communities with high opioid use disorder rates. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

Trends in BB/pellet gun injuries in children and teenagers in the United States, 1985-99.

PubMed

Nguyen, M H; Annest, J L; Mercy, J A; Ryan, G W; Fingerhut, L A

2002-09-01

To characterize national trends in non-fatal BB/pellet gun related injury rates for persons aged 19 years or younger in relation to trends in non-fatal and fatal firearm related injury rates and discuss these trends in light of injury prevention and violence prevention efforts. The National Electronic Injury Surveillance System (NEISS) includes approximately 100 hospitals with at least six beds that provide emergency services. These hospitals comprise a stratified probability sample of all US hospitals with emergency departments. The National Vital Statistics System (NVSS) is a complete census of all death certificates filed by states and is compiled annually. National data on BB/pellet gun related injuries and injury rates were examined along with fatal and non-fatal firearm related injuries and injury rates. Non-fatal injury data for all BB/pellet gun related injury cases from 1985 through 1999, and firearm related injury cases from 1993 through 1999 were obtained from hospital emergency department records using the NEISS. Firearm related deaths from 1985 through 1999 were obtained from the NVSS. BB/pellet gun related injury rates increased from age 3 years to a peak at age 13 years and declined thereafter. In contrast, firearm related injury and death rates increased gradually until age 13 and then increased sharply until age 18 years. For persons aged 19 years and younger, BB/pellet gun related injury rates increased from the late 1980s until the early 1990s and then declined until 1999; these injury rates per 100 000 population were 24.0 in 1988, 32.8 in 1992, and 18.3 in 1999. This trend was similar to those for fatal and non-fatal firearm related injury rates per 100 000 which were 4.5 in 1985, 7.8 in 1993, and 4.3 in 1999 (fatal) and 38.6 in 1993 and 16.3 in 1999 (non-fatal). In 1999, an estimated 14 313 (95% confidence interval (CI) 12 025 to 16 601) cases with non-fatal BB/pellet gun injuries and an estimated 12 748 (95% CI 7881-17 615) cases with non-fatal firearm related injuries among persons aged 19 years and younger were treated in US hospital emergency departments. BB/pellet gun related and firearm related injury rates show similar declines since the early 1990s. These declines coincide with a growing number of prevention efforts aimed at reducing injuries to children from unsupervised access to guns and from youth violence. Evaluations at the state and local level are needed to determine true associations.

Vital signs: Repeat births among teens - United States, 2007-2010.

PubMed

2013-04-05

Teen childbearing has potential negative health, economic, and social consequences for mother and child. Repeat teen childbearing further constrains the mother's education and employment possibilities. Rates of preterm and low birth weight are higher in teens with a repeat birth, compared with first births. To assess patterns of repeat childbearing and postpartum contraceptive use among teens, CDC analyzed natality data from the National Vital Statistics System (NVSS) and the Pregnancy Risk Assessment Monitoring System (PRAMS) from 2007-2010. Based on 2010 NVSS data from all 50 states and the District of Columbia, of more than 367,000 births to teens aged 15-19 years, 18.3% were repeat births. The percentage of teen births that represented repeat births decreased by 6.2% between 2007 and 2010. Disparities in repeat teen births exist by race/ethnicity, with the highest percentages found among American Indian/Alaska Natives (21.6%), Hispanics (20.9%), and non-Hispanic blacks (20.4%) and lowest among non-Hispanic whites (14.8%). Wide geographic disparities in the percentage of teen births that were repeat births also exist, ranging from 22% in Texas to 10% in New Hampshire. PRAMS data from 16 reporting areas (15 states and New York City) indicate that 91.2% of teen mothers used a contraceptive method 2-6 months after giving birth, but only 22.4% of teen mothers used the most effective methods. Teens with a previous live birth were significantly more likely to use the most effective methods postpartum compared with those with no prior live birth (29.6% versus 20.9%, respectively). Non-Hispanic white and Hispanic teens were significantly more likely to use the most effective methods than non-Hispanic black teens (24.6% and 27.9% versus 14.3%, respectively). The percentage of teens reporting postpartum use of the most effective methods varied greatly geographically across the PRAMS reporting areas, ranging from 50.3% in Colorado to 7.2% in New York State. Although the prevalence of repeat teen birth has declined in recent years, nearly one in five teen births is a repeat birth. Large disparities exist in repeat teen births and use of the most effective contraceptive methods postpartum, which was reported by fewer than one out of four teen mothers. Evidence-based approaches are needed to reduce repeat teen childbearing. These include linking pregnant and parenting teens to home visiting and similar programs that address a broad range of needs, and offering postpartum contraception to teens, including long-acting methods of reversible contraception.

Suicide Trends Among and Within Urbanization Levels by Sex, Race/Ethnicity, Age Group, and Mechanism of Death - United States, 2001-2015.

PubMed

Ivey-Stephenson, Asha Z; Crosby, Alex E; Jack, Shane P D; Haileyesus, Tadesse; Kresnow-Sedacca, Marcie-Jo

2017-10-06

Suicide is a public health problem and one of the top 10 leading causes of death in the United States. Substantial geographic variations in suicide rates exist, with suicides in rural areas occurring at much higher rates than those occurring in more urban areas. Understanding demographic trends and mechanisms of death among and within urbanization levels is important to developing and targeting future prevention efforts. 2001-2015. Mortality data from the National Vital Statistics System (NVSS) include demographic, geographic, and cause of death information derived from death certificates filed in the 50 states and the District of Columbia. NVSS was used to identify suicide deaths, defined by International Classification of Diseases, 10th Revision (ICD-10) underlying cause of death codes X60-X84, Y87.0, and U03. This report examines annual county level trends in suicide rates during 2001-2015 among and within urbanization levels by select demographics and mechanisms of death. Counties were collapsed into three urbanization levels using the 2006 National Center for Health Statistics classification scheme. Suicide rates increased across the three urbanization levels, with higher rates in nonmetropolitan/rural counties than in medium/small or large metropolitan counties. Each urbanization level experienced substantial annual rate changes at different times during the study period. Across urbanization levels, suicide rates were consistently highest for men and non-Hispanic American Indian/Alaska Natives compared with rates for women and other racial/ethnic groups; however, rates were highest for non-Hispanic whites in more metropolitan counties. Trends indicate that suicide rates for non-Hispanic blacks were lowest in nonmetropolitan/rural counties and highest in more urban counties. Increases in suicide rates occurred for all age groups across urbanization levels, with the highest rates for persons aged 35-64 years. For mechanism of death, greater increases in rates of suicide by firearms and hanging/suffocation occurred across all urbanization levels; rates of suicide by firearms in nonmetropolitan/rural counties were almost two times that of rates in larger metropolitan counties. Suicide rates in nonmetropolitan/rural counties are consistently higher than suicide rates in metropolitan counties. These trends also are observed by sex, race/ethnicity, age group, and mechanism of death. Interventions to prevent suicides should be ongoing, particularly in rural areas. Comprehensive suicide prevention efforts might include leveraging protective factors and providing innovative prevention strategies that increase access to health care and mental health care in rural communities. In addition, distribution of socioeconomic factors varies in different communities and needs to be better understood in the context of suicide prevention.

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

Xia, Jun-Qing; Cuoco, Alessandro; Branchini, Enzo

Building on our previous cross-correlation analysis (Xia et al. 2011) between the isotropic γ-ray background (IGRB) and different tracers of the large-scale structure of the universe, we update our results using 60 months of data from the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope (Fermi). For this study, we perform a cross-correlation analysis both in configuration and spherical harmonics space between the IGRB and objects that may trace the astrophysical sources of the IGRB: QSOs in the Sloan Digital Sky Survey (SDSS) DR6, the SDSS DR8 Main Galaxy Sample, luminous red galaxies (LRGs) in the SDSS catalog, infrared-selected galaxies in the Two Micron All Sky Survey (2MASS), and radio galaxies in the NRAO VLA Sky Survey (NVSS). The benefit of correlating the Fermi-LAT signal with catalogs of objects at various redshifts is to provide tomographic information on the IGRB, which is crucial in separating the various contributions and clarifying its origin. The main result is that, unlike in our previous analysis, we now observe a significant (>3.5σ) cross-correlation signal on angular scales smaller than 1° in the NVSS, 2MASS, and QSO cases and, at lower statistical significance (~3.0σ), with SDSS galaxies. The signal is stronger in two energy bands, E > 0.5 GeV and E > 1 GeV, but it is also seen at E > 10 GeV. No cross-correlation signal is detected between Fermi data and the LRGs. These results are robust against the choice of the statistical estimator, estimate of errors, map cleaning procedure, and instrumental effects. Finally, we test the hypothesis that the IGRB observed by Fermi-LAT originates from the summed contributions of three types of unresolved extragalactic sources: BL Lacertae objects (BL Lacs), flat spectrum radio quasars (FSRQs), and star-forming galaxies (SFGs). Finally, we find that a model in which the IGRB is mainly produced by SFGs (more » $$72_{-37}^{+23}$$% with 2σ errors), with BL Lacs and FSRQs giving a minor contribution, provides a good fit to the data. We also consider a possible contribution from misaligned active galactic nuclei, and we find that, depending on the details of the model and its uncertainty, they can also provide a substantial contribution, partly degenerate with the SFG one.« less

Trends in Suicide by Level of Urbanization - United States, 1999-2015.

PubMed

Kegler, Scott R; Stone, Deborah M; Holland, Kristin M

2017-03-17

Suicide is a major and continuing public health concern in the United States. During 1999-2015, approximately 600,000 U.S. residents died by suicide, with the highest annual rate occurring in 2015 (1). Annual county-level mortality data from the National Vital Statistics System (NVSS) and annual county-level population data from the U.S. Census Bureau were used to analyze suicide rate trends during 1999-2015, with special emphasis on comparing more urban and less urban areas. U.S. counties were grouped by level of urbanization using a six-level classification scheme. To evaluate rate trends, joinpoint regression methodology was applied to the time-series data for each level of urbanization. Suicide rates significantly increased over the study period for all county groupings and accelerated significantly in 2007-2008 for the medium metro, small metro, and non-metro groupings. Understanding suicide trends by urbanization level can help identify geographic areas of highest risk and focus prevention efforts. Communities can benefit from implementing policies, programs, and practices based on the best available evidence regarding suicide prevention and key risk factors. Many approaches are applicable regardless of urbanization level, whereas certain strategies might be particularly relevant in less urban areas affected by difficult economic conditions, limited access to helping services, and social isolation.

Heart Disease Death Rates Among Blacks and Whites Aged ≥35 Years — United States, 1968–2015

PubMed Central

Van Dyke, Miriam; Greer, Sophia; Odom, Erika; Schieb, Linda; Vaughan, Adam; Kramer, Michael; Casper, Michele

2018-01-01

Problem/Condition Heart disease is the leading cause of death in the United States. In 2015, heart disease accounted for approximately 630,000 deaths, representing one in four deaths in the United States. Although heart disease death rates decreased 68% for the total population from 1968 to 2015, marked disparities in decreases exist by race and state. Period Covered 1968–2015. Description of System The National Vital Statistics System (NVSS) data on deaths in the United States were abstracted for heart disease using diagnosis codes from the eighth, ninth, and tenth revisions of the International Classification of Diseases (ICD-8, ICD-9, and ICD-10) for 1968–2015. Population estimates were obtained from NVSS files. National and state-specific heart disease death rates for the total population and by race for adults aged ≥35 years were calculated for 1968–2015. National and state-specific black-white heart disease mortality ratios also were calculated. Death rates were age standardized to the 2000 U.S. standard population. Joinpoint regression was used to perform time trend analyses. Results From 1968 to 2015, heart disease death rates decreased for the total U.S. population among adults aged ≥35 years, from 1,034.5 to 327.2 per 100,000 population, respectively, with variations in the magnitude of decreases by race and state. Rates decreased for the total population an average of 2.4% per year, with greater average decreases among whites (2.4% per year) than blacks (2.2% per year). At the national level, heart disease death rates for blacks and whites were similar at the start of the study period (1968) but began to diverge in the late 1970s, when rates for blacks plateaued while rates for whites continued to decrease. Heart disease death rates among blacks remained higher than among whites for the remainder of the study period. Nationwide, the black-white ratio of heart disease death rates increased from 1.04 in 1968 to 1.21 in 2015, with large increases occurring during the 1970s and 1980s followed by small but steady increases until approximately 2005. Since 2005, modest decreases have occurred in the black-white ratio of heart disease death rates at the national level. The majority of states had increases in black-white mortality ratios from 1968 to 2015. The number of states with black-white mortality ratios >1 increased from 16 (40%) to 27 (67.5%). Interpretation Although heart disease death rates decreased both for blacks and whites from 1968 to 2015, substantial differences in decreases were found by race and state. At the national level and in most states, blacks experienced smaller decreases in heart disease death rates than whites for the majority of the period. Overall, the black-white disparity in heart disease death rates increased from 1968 to 2005, with a modest decrease from 2005 to 2015. Public Health Action Since 1968, substantial increases have occurred in black-white disparities of heart disease death rates in the United States at the national level and in many states. These increases appear to be due to faster decreases in heart disease death rates for whites than blacks, particularly from the late 1970s until the mid-2000s. Despite modest decreases in black-white disparities at the national level since 2005, in 2015, heart disease death rates were 21% higher among blacks than among whites. This study demonstrates the use of NVSS data to conduct surveillance of heart disease death rates by race and of black-white disparities in heart disease death rates. Continued surveillance of temporal trends in heart disease death rates by race can provide valuable information to policy makers and public health practitioners working to reduce heart disease death rates both for blacks and whites and disparities between blacks and whites. PMID:29596406

Firearm homicides and suicides in major metropolitan areas - United States, 2006-2007 and 2009-2010.

PubMed

2013-08-02

Firearm homicides and suicides are a continuing public health concern in the United States. During 2009-2010, a total of 22,571 firearm homicides and 38,126 firearm suicides occurred among U.S. residents. This includes 3,397 firearm homicides and 1,548 firearm suicides among persons aged 10-19 years; the firearm homicide rate for this age group was slightly above the all-ages rate. This report updates an earlier report that provided statistics on firearm homicides and suicides in major metropolitan areas for 2006-2007, with special emphasis on persons aged 10-19 years in recognition of the importance of early prevention efforts. Firearm homicide and suicide rates were calculated for the 50 most populous U.S. metropolitan statistical areas (MSAs) for 2009-2010 using mortality data from the National Vital Statistics System (NVSS) and population data from the U.S. Census Bureau. Comparison statistics were recalculated for 2006-2007 to reflect revisions to MSA delineations and population estimates subsequent to the earlier report. Although the firearm homicide rate for large MSAs collectively remained above the national rate during 2009-2010, more than 75% of these MSAs showed a decreased rate from 2006-2007, largely accounting for a national decrease. The firearm homicide rate for persons aged 10-19 years exceeded the all-ages rate in many of these MSAs during 2009-2010, similar to the earlier reporting period. Conversely, although the firearm suicide rate for large MSAs collectively remained below the national rate during 2009-2010, nearly 75% of these MSAs showed an increased rate from 2006-2007, paralleling the national trend. Firearm suicide rates among persons aged 10-19 years were low compared with all-ages rates during both periods. These patterns can inform the development and monitoring of strategies directed at reducing firearm-related violence.

Trends in BB/pellet gun injuries in children and teenagers in the United States, 1985–99

PubMed Central

Nguyen, M; Annest, J; Mercy, J; Ryan, G; Fingerhut, L

2002-01-01

Objective: To characterize national trends in non-fatal BB/pellet gun related injury rates for persons aged 19 years or younger in relation to trends in non-fatal and fatal firearm related injury rates and discuss these trends in light of injury prevention and violence prevention efforts. Setting: The National Electronic Injury Surveillance System (NEISS) includes approximately 100 hospitals with at least six beds that provide emergency services. These hospitals comprise a stratified probability sample of all US hospitals with emergency departments. The National Vital Statistics System (NVSS) is a complete census of all death certificates filed by states and is compiled annually. Methods: National data on BB/pellet gun related injuries and injury rates were examined along with fatal and non-fatal firearm related injuries and injury rates. Non-fatal injury data for all BB/pellet gun related injury cases from 1985 through 1999, and firearm related injury cases from 1993 through 1999 were obtained from hospital emergency department records using the NEISS. Firearm related deaths from 1985 through 1999 were obtained from the NVSS. Results: BB/pellet gun related injury rates increased from age 3 years to a peak at age 13 years and declined thereafter. In contrast, firearm related injury and death rates increased gradually until age 13 and then increased sharply until age 18 years. For persons aged 19 years and younger, BB/pellet gun related injury rates increased from the late 1980s until the early 1990s and then declined until 1999; these injury rates per 100 000 population were 24.0 in 1988, 32.8 in 1992, and 18.3 in 1999. This trend was similar to those for fatal and non-fatal firearm related injury rates per 100 000 which were 4.5 in 1985, 7.8 in 1993, and 4.3 in 1999 (fatal) and 38.6 in 1993 and 16.3 in 1999 (non-fatal). In 1999, an estimated 14 313 (95% confidence interval (CI) 12 025 to 16 601) cases with non-fatal BB/pellet gun injuries and an estimated 12 748 (95% CI 7881–17 615) cases with non-fatal firearm related injuries among persons aged 19 years and younger were treated in US hospital emergency departments. Conclusions: BB/pellet gun related and firearm related injury rates show similar declines since the early 1990s. These declines coincide with a growing number of prevention efforts aimed at reducing injuries to children from unsupervised access to guns and from youth violence. Evaluations at the state and local level are needed to determine true associations. PMID:12226113

TOMOGRAPHY OF THE FERMI-LAT γ-RAY DIFFUSE EXTRAGALACTIC SIGNAL VIA CROSS CORRELATIONS WITH GALAXY CATALOGS

DOE PAGES

Xia, Jun-Qing; Cuoco, Alessandro; Branchini, Enzo; ...

2015-03-24

Building on our previous cross-correlation analysis (Xia et al. 2011) between the isotropic γ-ray background (IGRB) and different tracers of the large-scale structure of the universe, we update our results using 60 months of data from the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope (Fermi). For this study, we perform a cross-correlation analysis both in configuration and spherical harmonics space between the IGRB and objects that may trace the astrophysical sources of the IGRB: QSOs in the Sloan Digital Sky Survey (SDSS) DR6, the SDSS DR8 Main Galaxy Sample, luminous red galaxies (LRGs) in the SDSS catalog, infrared-selected galaxies in the Two Micron All Sky Survey (2MASS), and radio galaxies in the NRAO VLA Sky Survey (NVSS). The benefit of correlating the Fermi-LAT signal with catalogs of objects at various redshifts is to provide tomographic information on the IGRB, which is crucial in separating the various contributions and clarifying its origin. The main result is that, unlike in our previous analysis, we now observe a significant (>3.5σ) cross-correlation signal on angular scales smaller than 1° in the NVSS, 2MASS, and QSO cases and, at lower statistical significance (~3.0σ), with SDSS galaxies. The signal is stronger in two energy bands, E > 0.5 GeV and E > 1 GeV, but it is also seen at E > 10 GeV. No cross-correlation signal is detected between Fermi data and the LRGs. These results are robust against the choice of the statistical estimator, estimate of errors, map cleaning procedure, and instrumental effects. Finally, we test the hypothesis that the IGRB observed by Fermi-LAT originates from the summed contributions of three types of unresolved extragalactic sources: BL Lacertae objects (BL Lacs), flat spectrum radio quasars (FSRQs), and star-forming galaxies (SFGs). Finally, we find that a model in which the IGRB is mainly produced by SFGs (more » $$72_{-37}^{+23}$$% with 2σ errors), with BL Lacs and FSRQs giving a minor contribution, provides a good fit to the data. We also consider a possible contribution from misaligned active galactic nuclei, and we find that, depending on the details of the model and its uncertainty, they can also provide a substantial contribution, partly degenerate with the SFG one.« less

Heart Disease Death Rates Among Blacks and Whites Aged ≥35 Years - United States, 1968-2015.

PubMed

Van Dyke, Miriam; Greer, Sophia; Odom, Erika; Schieb, Linda; Vaughan, Adam; Kramer, Michael; Casper, Michele

2018-03-30

Heart disease is the leading cause of death in the United States. In 2015, heart disease accounted for approximately 630,000 deaths, representing one in four deaths in the United States. Although heart disease death rates decreased 68% for the total population from 1968 to 2015, marked disparities in decreases exist by race and state. 1968-2015. The National Vital Statistics System (NVSS) data on deaths in the United States were abstracted for heart disease using diagnosis codes from the eighth, ninth, and tenth revisions of the International Classification of Diseases (ICD-8, ICD-9, and ICD-10) for 1968-2015. Population estimates were obtained from NVSS files. National and state-specific heart disease death rates for the total population and by race for adults aged ≥35 years were calculated for 1968-2015. National and state-specific black-white heart disease mortality ratios also were calculated. Death rates were age standardized to the 2000 U.S. standard population. Joinpoint regression was used to perform time trend analyses. From 1968 to 2015, heart disease death rates decreased for the total U.S. population among adults aged ≥35 years, from 1,034.5 to 327.2 per 100,000 population, respectively, with variations in the magnitude of decreases by race and state. Rates decreased for the total population an average of 2.4% per year, with greater average decreases among whites (2.4% per year) than blacks (2.2% per year). At the national level, heart disease death rates for blacks and whites were similar at the start of the study period (1968) but began to diverge in the late 1970s, when rates for blacks plateaued while rates for whites continued to decrease. Heart disease death rates among blacks remained higher than among whites for the remainder of the study period. Nationwide, the black-white ratio of heart disease death rates increased from 1.04 in 1968 to 1.21 in 2015, with large increases occurring during the 1970s and 1980s followed by small but steady increases until approximately 2005. Since 2005, modest decreases have occurred in the black-white ratio of heart disease death rates at the national level. The majority of states had increases in black-white mortality ratios from 1968 to 2015. The number of states with black-white mortality ratios >1 increased from 16 (40%) to 27 (67.5%). Although heart disease death rates decreased both for blacks and whites from 1968 to 2015, substantial differences in decreases were found by race and state. At the national level and in most states, blacks experienced smaller decreases in heart disease death rates than whites for the majority of the period. Overall, the black-white disparity in heart disease death rates increased from 1968 to 2005, with a modest decrease from 2005 to 2015. Since 1968, substantial increases have occurred in black-white disparities of heart disease death rates in the United States at the national level and in many states. These increases appear to be due to faster decreases in heart disease death rates for whites than blacks, particularly from the late 1970s until the mid-2000s. Despite modest decreases in black-white disparities at the national level since 2005, in 2015, heart disease death rates were 21% higher among blacks than among whites. This study demonstrates the use of NVSS data to conduct surveillance of heart disease death rates by race and of black-white disparities in heart disease death rates. Continued surveillance of temporal trends in heart disease death rates by race can provide valuable information to policy makers and public health practitioners working to reduce heart disease death rates both for blacks and whites and disparities between blacks and whites.

VizieR Online Data Catalog: Texas-Oxford NVSS (TONS) radio galaxies (Brand+, 2005)

NASA Astrophysics Data System (ADS)

Brand, K.; Rawlings, S.; Hill, G. J.; Tufts, J. R.

2005-10-01

Optical spectra were obtained during the period 2000 October-2003 May on the 2.6-m Nordic Optical Telescope (NOT) using the Andalucia faint object spectrograph, the 4.2-m William Herschel telescope (WHT) using ISIS, the 2.7-m Smith reflector at McDonald with the Imaging Grism Instrument (IGI), and the Hobby-Eberly Telescope (HET) using the Marcario low-resolution spectrograph (LRS). (3 data files).

A radio spectral index map and catalogue at 147-1400 MHz covering 80 per cent of the sky

NASA Astrophysics Data System (ADS)

de Gasperin, F.; Intema, H. T.; Frail, D. A.

2018-03-01

The radio spectral index is a powerful probe for classifying cosmic radio sources and understanding the origin of the radio emission. Combining data at 147 MHz and 1.4 GHz from the TIFR GMRT Sky Survey (TGSS) and the NRAO VLA Sky Survey (NVSS), we produced a large-area radio spectral index map of ˜80 per cent of the sky (Dec. > - 40 deg), as well as a radio spectral index catalogue containing 1396 515 sources, of which 503 647 are not upper or lower limits. Almost every TGSS source has a detected counterpart, while this is true only for 36 per cent of NVSS sources. We released both the map and the catalogue to the astronomical community. The catalogue is analysed to discover systematic behaviours in the cosmic radio population. We find a differential spectral behaviour between faint and bright sources as well as between compact and extended sources. These trends are explained in terms of radio galaxy evolution. We also confirm earlier reports of an excess of steep-spectrum sources along the galactic plane. This corresponds to 86 compact and steep-spectrum source in excess compared to expectations. The properties of this excess are consistent with normal non-recycled pulsars, which may have been missed by pulsation searches due to larger than average scattering along the line of sight.

Firearm injuries in the United States.

PubMed

Fowler, Katherine A; Dahlberg, Linda L; Haileyesus, Tadesse; Annest, Joseph L

2015-10-01

This paper examines the epidemiology of fatal and nonfatal firearm violence in the United States. Trends over two decades in homicide, assault, self-directed and unintentional firearm injuries are described along with current demographic characteristics of victimization and health impact. Fatal firearm injury data were obtained from the National Vital Statistics System (NVSS). Nonfatal firearm injury data were obtained from the National Electronic Injury Surveillance System (NEISS). Trends were tested using Joinpoint regression analyses. CDC Cost of Injury modules were used to estimate costs associated with firearm deaths and injuries. More than 32,000 persons die and over 67,000 persons are injured by firearms each year. Case fatality rates are highest for self-harm related firearm injuries, followed by assault-related injuries. Males, racial/ethnic minority populations, and young Americans (with the exception of firearm suicide) are disproportionately affected. The severity of such injuries is distributed relatively evenly across outcomes from outpatient treatment to hospitalization to death. Firearm injuries result in over $48 billion in medical and work loss costs annually, particularly fatal firearm injuries. From 1993 to 1999, rates of firearm violence declined significantly. Declines were seen in both fatal and nonfatal firearm violence and across all types of intent. While unintentional firearm deaths continued to decline from 2000 to 2012, firearm suicides increased and nonfatal firearm assaults increased to their highest level since 1995. Firearm injuries are an important public health problem in the United States, contributing substantially each year to premature death, illness, and disability. Understanding the nature and impact of the problem is only a first step toward preventing firearm violence. A science-driven approach to understand risk and protective factors and identify effective solutions is key to achieving measurable reductions in firearm violence. Published by Elsevier Inc.

Firearm injuries in the United States

PubMed Central

Fowler, Katherine A.; Dahlberg, Linda L.; Haileyesus, Tadesse; Annest, Joseph L.

2015-01-01

Objective This paper examines the epidemiology of fatal and nonfatal firearm violence in the United States. Trends over two decades in homicide, assault, self-directed and unintentional firearm injuries are described along with current demographic characteristics of victimization and health impact. Method Fatal firearm injury data were obtained from the National Vital Statistics System (NVSS). Nonfatal firearm injury data were obtained from the National Electronic Injury Surveillance System (NEISS). Trends were tested using Joinpoint regression analyses. CDC Cost of Injury modules were used to estimate costs associated with firearm deaths and injuries. Results More than 32,000 persons die and over 67,000 persons are injured by firearms each year. Case fatality rates are highest for self-harm related firearm injuries, followed by assault-related injuries. Males, racial/ethnic minority populations, and young Americans (with the exception of firearm suicide) are disproportionately affected. The severity of such injuries is distributed relatively evenly across outcomes from outpatient treatment to hospitalization to death. Firearm injuries result in over $48 billion in medical and work loss costs annually, particularly fatal firearm injuries. From 1993 to 1999, rates of firearm violence declined significantly. Declines were seen in both fatal and nonfatal firearm violence and across all types of intent. While unintentional firearm deaths continued to decline from 2000 to 2012, firearm suicides increased and nonfatal firearm assaults increased to their highest level since 1995. Conclusion Firearm injuries are an important public health problem in the United States, contributing substantially each year to premature death, illness, and disability. Understanding the nature and impact of the problem is only a first step toward preventing firearm violence. A science-driven approach to understand risk and protective factors and identify effective solutions is key to achieving measurable reductions in firearm violence. PMID:26116133

Mapping the integrated Sachs-Wolfe effect

NASA Astrophysics Data System (ADS)

Manzotti, A.; Dodelson, S.

2014-12-01

On large scales, the anisotropies in the cosmic microwave background (CMB) reflect not only the primordial density field but also the energy gain when photons traverse decaying gravitational potentials of large scale structure, what is called the integrated Sachs-Wolfe (ISW) effect. Decomposing the anisotropy signal into a primordial piece and an ISW component, the main secondary effect on large scales, is more urgent than ever as cosmologists strive to understand the Universe on those scales. We present a likelihood technique for extracting the ISW signal combining measurements of the CMB, the distribution of galaxies, and maps of gravitational lensing. We test this technique with simulated data showing that we can successfully reconstruct the ISW map using all the data sets together. Then we present the ISW map obtained from a combination of real data: the NRAO VLA sky survey (NVSS) galaxy survey, temperature anisotropies, and lensing maps made by the Planck satellite. This map shows that, with the data sets used and assuming linear physics, there is no evidence, from the reconstructed ISW signal in the Cold Spot region, for an entirely ISW origin of this large scale anomaly in the CMB. However a large scale structure origin from low redshift voids outside the NVSS redshift range is still possible. Finally we show that future surveys, thanks to a better large scale lensing reconstruction will be able to improve the reconstruction signal to noise which is now mainly coming from galaxy surveys.

The Cosmological Evolution of Radio Sources with CENSORS

NASA Technical Reports Server (NTRS)

Brookes, Mairi; Best, Philip; Peacock, John; Dunlop, James; Rottgering, Huub

2006-01-01

The CENSORS survey, selected from the NVSS, has been followed up using EIS, K-band imaging and spectroscopic observations to produce a radio sample capable of probing the source density in the regime: z greater than 2.5. With a current spectroscopic completeness of 62%, CENSORS has been used in direct modeling of RLF evolution and in V/V(sub max) tests. There is evidence for a shallow decline in number density of source in the luminosity range 10(sup 26) - 10(sup 27)WHz(sup -1) at 1.4GHz.

VizieR Online Data Catalog: 100-Mpc-scale structures of radio galaxies (Brand+, 2003)

NASA Astrophysics Data System (ADS)

Brand, K.; Rawlings, S.; Hill, G. J.; Lacy, M.; Mitchell, E.; Tufts, J.

2003-09-01

The TONS08 survey is in one of the areas covered by the 7CRS (Willott et al., 2002MNRAS.335.1120W) and the TexOx-1000 (TOOT) survey (Hill & Rawlings, 2002, ASP Conf. Proc., Leiden. Astron. Soc. Pac., San Francisco). It covers the region 08h 10m 20s <= RA <= 08h 29m 20s and 24{deg} 10' 00" <= DE<= 29{deg} 30' 00" (J2000). Unlike the low-frequency-selected 7CRS and TOOT, the TONS08 survey is selected at 1.4GHz from the NVSS. (1 data file).

Astronomers Find Enormous Hole in the Universe

NASA Astrophysics Data System (ADS)

2007-08-01

Astronomers have found an enormous hole in the Universe, nearly a billion light-years across, empty of both normal matter such as stars, galaxies, and gas, and the mysterious, unseen "dark matter." While earlier studies have shown holes, or voids, in the large-scale structure of the Universe, this new discovery dwarfs them all. Void Illustration Hole in Universe revealed by its effect on Cosmic Microwave Background radiation. CREDIT: Bill Saxton, NRAO/AUI/NSF, NASA Click on image for page of graphics and detailed information "Not only has no one ever found a void this big, but we never even expected to find one this size," said Lawrence Rudnick of the University of Minnesota. Rudnick, along with Shea Brown and Liliya R. Williams, also of the University of Minnesota, reported their findings in a paper accepted for publication in the Astrophysical Journal. Astronomers have known for years that, on large scales, the Universe has voids largely empty of matter. However, most of these voids are much smaller than the one found by Rudnick and his colleagues. In addition, the number of discovered voids decreases as the size increases. "What we've found is not normal, based on either observational studies or on computer simulations of the large-scale evolution of the Universe," Williams said. The astronomers drew their conclusion by studying data from the NRAO VLA Sky Survey (NVSS), a project that imaged the entire sky visible to the Very Large Array (VLA) radio telescope, part of the National Science Foundation's National Radio Astronomy Observatory (NRAO). Their careful study of the NVSS data showed a remarkable drop in the number of galaxies in a region of sky in the constellation Eridanus. "We already knew there was something different about this spot in the sky," Rudnick said. The region had been dubbed the "WMAP Cold Spot," because it stood out in a map of the Cosmic Microwave Background (CMB) radiation made by the Wilkinson Microwave Anisotopy Probe (WMAP) satellite, launched by NASA in 2001. The CMB, faint radio waves that are the remnant radiation from the Big Bang, is the earliest "baby picture" available of the Universe. Irregularities in the CMB show structures that existed only a few hundred thousand years after the Big Bang. The WMAP satellite measured temperature differences in the CMB that are only millionths of a degree. The cold region in Eridanus was discovered in 2004. Astronomers wondered if the cold spot was intrinsic to the CMB, and thus indicated some structure in the very early Universe, or whether it could be caused by something more nearby through which the CMB had to pass on its way to Earth. Finding the dearth of galaxies in that region by studying NVSS data resolved that question. "Although our surprising results need independent confirmation, the slightly colder temperature of the CMB in this region appears to be caused by a huge hole devoid of nearly all matter roughly 6-10 billion light-years from Earth," Rudnick said. How does a lack of matter cause a cooler temperature in the Big Bang's remnant radiation as seen from Earth? Photons of the CMB gain a small amount of energy when they pass through a region of space populated by matter. This effect is caused by the enigmatic "dark energy" that is accelerating the expansion of the Universe. This gain in photon energy makes the CMB appear slightly warmer in that direction. When the photons pass through an empty void, they lose a small amount of energy from this effect, and so the CMB radiation passing through such a region appears cooler. The acceleration of the Universe's expansion, and thus dark energy, were discovered less than a decade ago. The physical properties of dark energy are unknown, though it is by far the most abundant form of energy in the Universe today. Learning its nature is one of the most fundamental current problems in astrophysics. The NVSS imaged the roughly 82 percent of the sky visible from the New Mexico site of the VLA. The survey consists of 217,446 individual observations that consumed 2,940 hours of telescope time between 1993 and 1997. A set of 2,326 images was produced from the data, and these images are available via the NRAO Web site. The survey also produced a catalog of more than 1.8 million individual objects identifiable in the images. The NVSS has been cited in more than 1,200 scientific papers. NASA's WMAP satellite, using microwave amplifiers produced by NRAO's Central Development Laboratory, has yielded a wealth of new information about the age and history of the Universe, the emergence of the first stars, and the composition of the Universe. WMAP results have been extensively cited by scientists in a wide variety of astrophysical specialties. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc. This research at the University of Minnesota is supported by individual investigator grants from the NSF and NASA.

THE LOW-FREQUENCY RADIO CATALOG OF FLAT-SPECTRUM SOURCES

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

Massaro, F.; Giroletti, M.; D'Abrusco, R.

A well known property of the γ-ray sources detected by Cos-B in the 1970s, by the Compton Gamma-Ray Observatory in the 1990s, and recently by the Fermi observations is the presence of radio counterparts, particularly for those associated with extragalactic objects. This observational evidence is the basis of the radio-γ-ray connection established for the class of active galactic nuclei known as blazars. In particular, the main spectral property of the radio counterparts associated with γ-ray blazars is that they show a flat spectrum in the GHz frequency range. Our recent analysis dedicated to search blazar-like candidates as potential counterparts formore » the unidentified γ-ray sources allowed us to extend the radio-γ-ray connection in the MHz regime. We also showed that blazars below 1 GHz maintain flat radio spectra. Thus, on the basis of these new results, we assembled a low-frequency radio catalog of flat-spectrum sources built by combining the radio observations of the Westerbork Northern Sky Survey and of the Westerbork in the southern hemisphere catalog with those of the NRAO Very Large Array Sky survey (NVSS). This could be used in the future to search for new, unknown blazar-like counterparts of γ-ray sources. First, we found NVSS counterparts of Westerbork Synthesis Radio Telescope radio sources, and then we selected flat-spectrum radio sources according to a new spectral criterion, specifically defined for radio observations performed below 1 GHz. We also described the main properties of the catalog listing 28,358 radio sources and their logN-logS distributions. Finally, a comparison with the Green Bank 6 cm radio source catalog was performed to investigate the spectral shape of the low-frequency flat-spectrum radio sources at higher frequencies.« less

Nascent starbursts: a missing link in galaxy evolution

NASA Astrophysics Data System (ADS)

Roussel, Helene; Beck, Rainer; Condon, Jim; Helou, George; Smith, John-David

2005-06-01

We have identified a rare category of galaxies characterized by an extreme deficiency in synchro- tron radiation, relative to dust emission, and very high dust temperatures. We studied in detail the most extreme such object, and concluded in favor of a starburst just breaking out, less than one megayear old, in a galaxy having undergone no major star formation episode in the last 100 Myr. Such systems offer a perfect setting to study the initial conditions and early dynamics of starbursts and understand better the regulation of the infrared-radio continuum correlation in galaxies. For the prototypical nascent starburst, the mid-infrared spectrum is quite peculiar, suggesting tran- sient dust species and high optical depth; tracers of dust and molecular gas are the only indicators of unusual activity, and the active regions are likely very compact and dust-bounded, suppressing ionization. Only Spitzer data can provide the needed physical diagnostics for such regions. A sample of 25 nascent starbursts was drawn from the cross-correlation of the IRAS Faint Source Catalog and the NVSS VLA radio survey, and carefully selected based on our multi-wavelength VLA maps to span a range of infrared to radio ratios and luminosities. This sample allows a first step beyond studying prototypes toward a statistical analysis addressing systematic physical pro- perties, classification and search for starburst development sequences. We propose imaging and spectroscopic observations from 3 to 160 microns to characterize the state of the interstellar medium and the gas and dust excitation origin. Our aim is to learn from these unique systems how a star formation burst may develop in its very earliest phases, how it affects the fueling material and the host galaxy. Acquired observations of the radio continuum, cold molecular gas and tracers of shocks and HII regions will help us interpret the rich Spitzer data set and extract a coherent picture of the interstellar medium in our targets.

A Very Large Array Survey of Polar BAL Quasar Candidates

NASA Astrophysics Data System (ADS)

Olson, Kianna Alexandra; Brotherton, Michael S.; DiPompeo, Michael; Maithil, Jaya

2018-06-01

Polar broad absorption line quasars posses flat radio spectra and jets seen at small angles to the line of sight. Using the VLA we observed twelve polar broad absorption line quasar candidates at L (1.5GHz), C (4.5-5.5GHz), and X (8.5-9.5GHz) bands, and found that their cores display flat spectra. Compared to previous observations in the NVSS and First surveys, the peak flux densities all show significant variation σvar > 3, and brightness temperatures TB ≥ 1012K. Based on these findings, our quasars have the properties expected for objects that posses jets seen nearly pole on.

The MIXR sample or: how I learned to stop worrying and love multiwavelength catalogue cross-correlations

NASA Astrophysics Data System (ADS)

Mingo, Beatriz; Watson, Mike; Stewart, Gordon; Rosen, Simon; Blain, Andrew; Hardcastle, Martin; Mateos, Silvia; Carrera, Francisco; Ruiz, Angel; Pineau, Francois-Xavier

2016-08-01

We cross-match 3XMM, WISE and FIRST/NVSS to create the largest-to-date mid-IR, X-ray, and radio (MIXR) sample of galaxies and AGN. We use MIXR to triage sources and efficiently and accurately pre-classify them as star-forming galaxies or AGN, and to highlight bias and shortcomings in current AGN sample selection methods, paving the way for the next generation of instruments. Our results highlight key questions in AGN science, such as the need for a re-definition of the radio-loud/radio-quiet classification, and our observed lack of correlation between the kinetic (jet) and radiative (luminosity) output in AGN, which has dramatic potential consequences on our current understanding of AGN accretion, variability and feedback.

Broadband radio spectro-polarimetric observations of high-Faraday-rotation-measure AGN

NASA Astrophysics Data System (ADS)

Pasetto, Alice; Carrasco-González, Carlos; O'Sullivan, Shane; Basu, Aritra; Bruni, Gabriele; Kraus, Alex; Curiel, Salvador; Mack, Karl-Heinz

2018-06-01

We present broadband polarimetric observations of a sample of high-Faraday-rotation-measure (high-RM) active galactic nuclei (AGN) using the Karl. G. Jansky Very Large Array (JVLA) telescope from 1 to 2 GHz, and 4 to 12 GHz. The sample (14 sources) consists of very compact sources (linear resolution smaller than ≈5 kpc) that are unpolarized at 1.4 GHz in the NRAO VLA Sky Survey (NVSS). Total intensity data have been modeled using a combination of synchrotron components, revealing complex structure in their radio spectra. Depolarization modeling, through the so-called qu-fitting (the modeling of the fractional quantities of the Stokes Q and U parameters), has been performed on the polarized data using an equation that attempts to simplify the process of fitting many different depolarization models. These models can be divided into two major categories: external depolarization (ED) and internal depolarization (ID) models. Understanding which of the two mechanisms is the most representative would help the qualitative understanding of the AGN jet environment and whether it is embedded in a dense external magneto-ionic medium or if it is the jet-wind that causes the high RM and strong depolarization. This could help to probe the jet magnetic field geometry (e.g., helical or otherwise). This new high-sensitivity data shows a complicated behavior in the total intensity and polarization radio spectrum of individual sources. We observed the presence of several synchrotron components and Faraday components in their total intensity and polarized spectra. For the majority of our targets (12 sources), the depolarization seems to be caused by a turbulent magnetic field. Thus, our main selection criteria (lack of polarization at 1.4 GHz in the NVSS) result in a sample of sources with very large RMs and depolarization due to turbulent magnetic fields local to the source. These broadband JVLA data reveal the complexity of the polarization properties of this class of radio sources. We show how the new qu-fitting technique can be used to probe the magnetized radio source environment and to spectrally resolve the polarized components of unresolved radio sources.

Reduction and Analysis of GALFACTS Data in Search of Compact Variable Sources

NASA Astrophysics Data System (ADS)

Wenger, Trey; Barenfeld, S.; Ghosh, T.; Salter, C.

2012-01-01

The Galactic ALFA Continuum Transit Survey (GALFACTS) is an all-Arecibo sky, full-Stokes survey from 1225 to 1525 MHz using the multibeam Arecibo L-band Feed Array (ALFA). Using data from survey field N1, the first field covered by GALFACTS, we are searching for compact sources that vary in intensity and/or polarization. The multistep procedure for reducing the data includes radio frequency interference (RFI) removal, source detection, Gaussian fitting in multiple dimensions, polarization leakage calibration, and gain calibration. We have developed code to analyze and calculate the calibration parameters from the N1 calibration sources, and apply these to the data of the main run. For detected compact sources, our goal is to compare results from multiple passes over a source to search for rapid variability, as well as to compare our flux densities with those from the NRAO VLA Sky Survey (NVSS) to search for longer time-scale variations.

Disk–Jet Connection in Active Supermassive Black Holes in the Standard Accretion Disk Regime

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

Inoue, Yoshiyuki; Doi, Akihiro; Tanaka, Yasuyuki T.

We study the disk–jet connection in supermassive black holes by investigating the properties of their optical and radio emissions utilizing the SDSS DR7 and the NVSS catalogs. Our sample contains 7017 radio-loud quasars with detection both at 1.4 GHz and SDSS optical spectra. Using this radio-loud quasar sample, we investigate the correlation among the jet power (more » $${P}_{\\mathrm{jet}}$$), the bolometric disk luminosity ($${L}_{\\mathrm{disk}}$$), and the black hole mass ($${M}_{\\mathrm{BH}}$$) in the standard accretion disk regime. We find that the jet powers correlate with the bolometric disk luminosities as $$\\mathrm{log}{P}_{\\mathrm{jet}}=(0.96\\pm 0.012)\\mathrm{log}{L}_{\\mathrm{disk}}+(0.79\\pm 0.55)$$. This suggests the jet production efficiency of $${\\eta }_{\\mathrm{jet}}\\simeq {1.1}_{-0.76}^{+2.6}\\,\\times {10}^{-2}$$ assuming the disk radiative efficiency of 0.1, implying low black hole spin parameters and/or low magnetic flux for radio-loud quasars. But it can be also due to the dependence of this efficiency on the geometrical thickness of the accretion flow, which is expected to be small for quasars accreting at the disk Eddington ratios $$0.01\\lesssim \\lambda \\lesssim 0.3$$. This low jet production efficiency does not significantly increase even if we set the disk radiative efficiency to be 0.3. We also investigate the fundamental plane in our samples among $${P}_{\\mathrm{jet}}$$, $${L}_{\\mathrm{disk}}$$, and $${M}_{\\mathrm{BH}}$$. In conclusion, we could not find a statistically significant fundamental plane for radio-loud quasars in the standard accretion regime.« less

Disk–Jet Connection in Active Supermassive Black Holes in the Standard Accretion Disk Regime

DOE PAGES

Inoue, Yoshiyuki; Doi, Akihiro; Tanaka, Yasuyuki T.; ...

2017-05-04

We study the disk–jet connection in supermassive black holes by investigating the properties of their optical and radio emissions utilizing the SDSS DR7 and the NVSS catalogs. Our sample contains 7017 radio-loud quasars with detection both at 1.4 GHz and SDSS optical spectra. Using this radio-loud quasar sample, we investigate the correlation among the jet power (more » $${P}_{\\mathrm{jet}}$$), the bolometric disk luminosity ($${L}_{\\mathrm{disk}}$$), and the black hole mass ($${M}_{\\mathrm{BH}}$$) in the standard accretion disk regime. We find that the jet powers correlate with the bolometric disk luminosities as $$\\mathrm{log}{P}_{\\mathrm{jet}}=(0.96\\pm 0.012)\\mathrm{log}{L}_{\\mathrm{disk}}+(0.79\\pm 0.55)$$. This suggests the jet production efficiency of $${\\eta }_{\\mathrm{jet}}\\simeq {1.1}_{-0.76}^{+2.6}\\,\\times {10}^{-2}$$ assuming the disk radiative efficiency of 0.1, implying low black hole spin parameters and/or low magnetic flux for radio-loud quasars. But it can be also due to the dependence of this efficiency on the geometrical thickness of the accretion flow, which is expected to be small for quasars accreting at the disk Eddington ratios $$0.01\\lesssim \\lambda \\lesssim 0.3$$. This low jet production efficiency does not significantly increase even if we set the disk radiative efficiency to be 0.3. We also investigate the fundamental plane in our samples among $${P}_{\\mathrm{jet}}$$, $${L}_{\\mathrm{disk}}$$, and $${M}_{\\mathrm{BH}}$$. In conclusion, we could not find a statistically significant fundamental plane for radio-loud quasars in the standard accretion regime.« less

Planck 2015 results: XXI. The integrated Sachs-Wolfe effect

DOE PAGES

Ade, P. A. R.; Aghanim, N.; Arnaud, M.; ...

2016-09-20

Here, this paper presents a study of the integrated Sachs-Wolfe (ISW) effect from the Planck 2015 temperature and polarization data release. This secondary cosmic microwave background (CMB) anisotropy caused by the large-scale time-evolving gravitational potential is probed from different perspectives. The CMB is cross-correlated with different large-scale structure (LSS) tracers: radio sources from the NVSS catalogue; galaxies from the optical SDSS and the infrared WISE surveys; and the Planck 2015 convergence lensing map. The joint cross-correlation of the CMB with the tracers yields a detection at 4σ where most of the signal-to-noise is due to the Planck lensing and themore » NVSS radio catalogue. In fact, the ISW effect is detected from the Planck data only at ≈3σ (through the ISW-lensing bispectrum), which is similar to the detection level achieved by combining the cross-correlation signal coming from all the galaxy catalogues mentioned above. We study the ability of the ISW effect to place constraints on the dark-energy parameters; in particular, we show that Ω Λ is detected at more than 3σ. This cross-correlation analysis is performed only with the Planck temperature data, since the polarization scales available in the 2015 release do not permit significant improvement of the CMB-LSS cross-correlation detectability. Nevertheless, the Planck polarization data are used to study the anomalously large ISW signal previously reported through the aperture photometry on stacked CMB features at the locations of known superclusters and supervoids, which is in conflict with ΛCDM expectations. We find that the current Planck polarization data do not exclude that this signal could be caused by the ISW effect. In addition, the stacking of the Planck lensing map on the locations of superstructures exhibits a positive cross-correlation with these large-scale structures. Finally, we have improved our previous reconstruction of the ISW temperature fluctuations by combining the information encoded in all the previously mentioned LSS tracers. In particular, we construct a map of the ISW secondary anisotropies and the corresponding uncertainties map, obtained from simulations. Lastly, we also explore the reconstruction of the ISW anisotropies caused by the large-scale structure traced by the 2MASS Photometric Redshift Survey (2MPZ) by directly inverting the density field into the gravitational potential field.« less

The Last of FIRST: The Final Catalog and Source Identifications

NASA Astrophysics Data System (ADS)

Helfand, David J.; White, Richard L.; Becker, Robert H.

2015-03-01

The FIRST survey, begun over 20 years ago, provides the definitive high-resolution map of the radio sky. This Very Large Telescope (VLA) survey reaches a detection sensitivity of 1 mJy at 20 cm over a final footprint of 10,575 deg2 that is largely coincident with the Sloan Digital Sky Survey (SDSS) area. Both the images and a catalog containing 946,432 sources are available through the FIRST Web site (http://sundog.stsci.edu). We record here the authoritative survey history, including hardware and software changes that affect the catalog's reliability and completeness. In particular, we use recent observations taken with the JVLA to test various aspects of the survey data (astrometry, CLEAN bias, and the flux density scale). We describe a new, sophisticated algorithm for flagging potential sidelobes in this snapshot survey, and show that fewer than 10% of the cataloged objects are likely sidelobes, and that these are heavily concentrated at low flux densities and in the vicinity of bright sources, as expected. We also report a comparison of the survey with the NRAO VLA Sky Survey (NVSS), as well as a match of the FIRST catalog to the SDSS and Two Micron Sky Survey (2MASS) sky surveys. The NVSS match shows very good consistency in flux density scale and astrometry between the two surveys. The matches with 2MASS and SDSS indicate a systematic ~10-20 mas astrometric error with respect to the optical reference frame in all VLA data that has disappeared with the advent of the JVLA. We demonstrate strikingly different behavior between the radio matches to stellar objects and to galaxies in the optical and IR surveys reflecting the different radio populations present over the flux density range 1-1000 mJy. As the radio flux density declines, stellar counterparts (quasars) get redder and fainter, while galaxies get brighter and have colors that initially redden but then turn bluer near the FIRST detection limit. Implications for future radio sky surveys are also briefly discussed. In particular, we show that for radio source identification at faint optical magnitudes, high angular resolution observations are essential, and cannot be sacrificed in exchange for high signal-to-noise data. The value of a JVLA survey as a complement to Square Kilometer Array precursor surveys is briefly discussed.

Planck 2015 results. XXI. The integrated Sachs-Wolfe effect

NASA Astrophysics Data System (ADS)

Planck Collaboration; Ade, P. A. R.; Aghanim, N.; Arnaud, M.; Ashdown, M.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barreiro, R. B.; Bartolo, N.; Basak, S.; Battaner, E.; Benabed, K.; Benoît, A.; Benoit-Lévy, A.; Bernard, J.-P.; Bersanelli, M.; Bielewicz, P.; Bock, J. J.; Bonaldi, A.; Bonavera, L.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Bucher, M.; Burigana, C.; Butler, R. C.; Calabrese, E.; Cardoso, J.-F.; Casaponsa, B.; Catalano, A.; Challinor, A.; Chamballu, A.; Chiang, H. C.; Christensen, P. R.; Church, S.; Clements, D. L.; Colombi, S.; Colombo, L. P. L.; Combet, C.; Couchot, F.; Coulais, A.; Crill, B. P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R. D.; Davis, R. J.; de Bernardis, P.; de Rosa, A.; de Zotti, G.; Delabrouille, J.; Désert, F.-X.; Diego, J. M.; Dole, H.; Donzelli, S.; Doré, O.; Douspis, M.; Ducout, A.; Dupac, X.; Efstathiou, G.; Elsner, F.; Enßlin, T. A.; Eriksen, H. K.; Fergusson, J.; Fernandez-Cobos, R.; Finelli, F.; Forni, O.; Frailis, M.; Fraisse, A. A.; Franceschi, E.; Frejsel, A.; Galeotta, S.; Galli, S.; Ganga, K.; Génova-Santos, R. T.; Giard, M.; Giraud-Héraud, Y.; Gjerløw, E.; González-Nuevo, J.; Górski, K. M.; Gratton, S.; Gregorio, A.; Gruppuso, A.; Gudmundsson, J. E.; Hansen, F. K.; Hanson, D.; Harrison, D. L.; Henrot-Versillé, S.; Hernández-Monteagudo, C.; Herranz, D.; Hildebrandt, S. R.; Hivon, E.; Hobson, M.; Holmes, W. A.; Hornstrup, A.; Hovest, W.; Huffenberger, K. M.; Hurier, G.; Ilić, S.; Jaffe, A. H.; Jaffe, T. R.; Jones, W. C.; Juvela, M.; Keihänen, E.; Keskitalo, R.; Kisner, T. S.; Kneissl, R.; Knoche, J.; Kunz, M.; Kurki-Suonio, H.; Lagache, G.; Lähteenmäki, A.; Lamarre, J.-M.; Langer, M.; Lasenby, A.; Lattanzi, M.; Lawrence, C. R.; Leonardi, R.; Lesgourgues, J.; Levrier, F.; Liguori, M.; Lilje, P. B.; Linden-Vørnle, M.; López-Caniego, M.; Lubin, P. M.; Ma, Y.-Z.; Macías-Pérez, J. F.; Maggio, G.; Maino, D.; Mandolesi, N.; Mangilli, A.; Marcos-Caballero, A.; Maris, M.; Martin, P. G.; Martínez-González, E.; Masi, S.; Matarrese, S.; McGehee, P.; Meinhold, P. R.; Melchiorri, A.; Mendes, L.; Mennella, A.; Migliaccio, M.; Mitra, S.; Miville-Deschênes, M.-A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Moss, A.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Nati, F.; Natoli, P.; Netterfield, C. B.; Nørgaard-Nielsen, H. U.; Noviello, F.; Novikov, D.; Novikov, I.; Oxborrow, C. A.; Paci, F.; Pagano, L.; Pajot, F.; Paoletti, D.; Pasian, F.; Patanchon, G.; Perdereau, O.; Perotto, L.; Perrotta, F.; Pettorino, V.; Piacentini, F.; Piat, M.; Pierpaoli, E.; Pietrobon, D.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Popa, L.; Pratt, G. W.; Prézeau, G.; Prunet, S.; Puget, J.-L.; Rachen, J. P.; Reach, W. T.; Rebolo, R.; Reinecke, M.; Remazeilles, M.; Renault, C.; Renzi, A.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Rossetti, M.; Roudier, G.; Rubiño-Martín, J. A.; Rusholme, B.; Sandri, M.; Santos, D.; Savelainen, M.; Savini, G.; Schaefer, B. M.; Scott, D.; Seiffert, M. D.; Shellard, E. P. S.; Spencer, L. D.; Stolyarov, V.; Stompor, R.; Sudiwala, R.; Sunyaev, R.; Sutton, D.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J. A.; Terenzi, L.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Tuovinen, J.; Valenziano, L.; Valiviita, J.; Van Tent, F.; Vielva, P.; Villa, F.; Wade, L. A.; Wandelt, B. D.; Wehus, I. K.; Yvon, D.; Zacchei, A.; Zonca, A.

2016-09-01

This paper presents a study of the integrated Sachs-Wolfe (ISW) effect from the Planck 2015 temperature and polarization data release. This secondary cosmic microwave background (CMB) anisotropy caused by the large-scale time-evolving gravitational potential is probed from different perspectives. The CMB is cross-correlated with different large-scale structure (LSS) tracers: radio sources from the NVSS catalogue; galaxies from the optical SDSS and the infrared WISE surveys; and the Planck 2015 convergence lensing map. The joint cross-correlation of the CMB with the tracers yields a detection at 4σ where most of the signal-to-noise is due to the Planck lensing and the NVSS radio catalogue. In fact, the ISW effect is detected from the Planck data only at ≈3σ (through the ISW-lensing bispectrum), which is similar to the detection level achieved by combining the cross-correlation signal coming from all the galaxy catalogues mentioned above. We study the ability of the ISW effect to place constraints on the dark-energy parameters; in particular, we show that ΩΛ is detected at more than 3σ. This cross-correlation analysis is performed only with the Planck temperature data, since the polarization scales available in the 2015 release do not permit significant improvement of the CMB-LSS cross-correlation detectability. Nevertheless, the Planck polarization data are used to study the anomalously large ISW signal previously reported through the aperture photometry on stacked CMB features at the locations of known superclusters and supervoids, which is in conflict with ΛCDM expectations. We find that the current Planck polarization data do not exclude that this signal could be caused by the ISW effect. In addition, the stacking of the Planck lensing map on the locations of superstructures exhibits a positive cross-correlation with these large-scale structures. Finally, we have improved our previous reconstruction of the ISW temperature fluctuations by combining the information encoded in all the previously mentioned LSS tracers. In particular, we construct a map of the ISW secondary anisotropies and the corresponding uncertainties map, obtained from simulations. We also explore the reconstruction of the ISW anisotropies caused by the large-scale structure traced by the 2MASS Photometric Redshift Survey (2MPZ) by directly inverting the density field into the gravitational potential field.

Planck 2015 results: XXI. The integrated Sachs-Wolfe effect

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

Ade, P. A. R.; Aghanim, N.; Arnaud, M.

Here, this paper presents a study of the integrated Sachs-Wolfe (ISW) effect from the Planck 2015 temperature and polarization data release. This secondary cosmic microwave background (CMB) anisotropy caused by the large-scale time-evolving gravitational potential is probed from different perspectives. The CMB is cross-correlated with different large-scale structure (LSS) tracers: radio sources from the NVSS catalogue; galaxies from the optical SDSS and the infrared WISE surveys; and the Planck 2015 convergence lensing map. The joint cross-correlation of the CMB with the tracers yields a detection at 4σ where most of the signal-to-noise is due to the Planck lensing and themore » NVSS radio catalogue. In fact, the ISW effect is detected from the Planck data only at ≈3σ (through the ISW-lensing bispectrum), which is similar to the detection level achieved by combining the cross-correlation signal coming from all the galaxy catalogues mentioned above. We study the ability of the ISW effect to place constraints on the dark-energy parameters; in particular, we show that Ω Λ is detected at more than 3σ. This cross-correlation analysis is performed only with the Planck temperature data, since the polarization scales available in the 2015 release do not permit significant improvement of the CMB-LSS cross-correlation detectability. Nevertheless, the Planck polarization data are used to study the anomalously large ISW signal previously reported through the aperture photometry on stacked CMB features at the locations of known superclusters and supervoids, which is in conflict with ΛCDM expectations. We find that the current Planck polarization data do not exclude that this signal could be caused by the ISW effect. In addition, the stacking of the Planck lensing map on the locations of superstructures exhibits a positive cross-correlation with these large-scale structures. Finally, we have improved our previous reconstruction of the ISW temperature fluctuations by combining the information encoded in all the previously mentioned LSS tracers. In particular, we construct a map of the ISW secondary anisotropies and the corresponding uncertainties map, obtained from simulations. Lastly, we also explore the reconstruction of the ISW anisotropies caused by the large-scale structure traced by the 2MASS Photometric Redshift Survey (2MPZ) by directly inverting the density field into the gravitational potential field.« less

An Unlikely Radio Halo in the Low X-Ray Luminosity Galaxy Cluster RXCJ1514.9-1523

NASA Technical Reports Server (NTRS)

Marketvitch, M.; ZuHone, J. A.; Lee, D.; Giacintucci, S.; Dallacasa, D.; Venturi, T.; Brunetti, G.; Cassano, R.; Markevitch, M.; Athreya, R. M.

2011-01-01

Aims: We report the discovery of a giant radio halo in the galaxy cluster RXCJ1514,9-1523 at z=0.22 with a relatively low X-ray luminosity, L(sub X) (0.1-2.4kev) approx. 7 x 10(exp 44) ergs/s. Methods: This faint, diffuse radio source is detected with the Giant Meterwave Radio Telescope at 327 MHz. The source is barely detected at 1.4 GHz in a NVSS pointing that we have reanalyzed. Results: The integrated radio spectrum of the halo is quite steep, with a slope alpha = 1.6 between 327 MHz and 1.4 GHz. While giant radio halos are common in more X-ray luminous cluster mergers, there is a less than 10% probability to detect a halo in systems with L(sub X) < 8 x 10(exp 44) ergs/s. The detection of a new giant halo in this borderline luminosity regime can be particularly useful for discriminating between the competing theories for the origin of ultrarelativistic electrons in clusters. Furthermore, if our steep radio spectral index is confirmed by future deeper radio observations, this cluster would provide another example of the very rare, new class of ultra-steep spectrum radio halos, predicted by the model in which the cluster cosmic ray electrons are produced by turbulent reacceleration.

The Gamma-Ray Bright BL Lac Object RX J1211+2242

NASA Technical Reports Server (NTRS)

Beckmann, V.; Favre, P.; Tavecchio, F.; Bussien, T.; Fliri, J.; Wolter, A.

2004-01-01

RX J1211+2242 is an optically faint (B approximately equal to 19.2mag) but X-ray bright (f2-10kev = 5 x l0(exp -12)erg per square centimeter per second) AGN, which has been shown to be a BL Lac object at redshift z = 0.455. The ROSAT X-ray, Calar Alto optical, and NVSS radio data suggest that the peak of the synchrotron emission of this object is at energies as high as several keV. BeppoSAX observations have been carried out simultaneously with optical observations in order to extend the coverage to higher energies. The new data indeed indicate a turn-over in the 2 - 10keV energy region. We propose that RX J1211+2242 is the counterpart of the unidentified EGRET source 3EG J1212+2304, making it a gamma-ray emitter with properties similar to, for example, Markarian 501 in its bright state, though being at a much larger distance.

Galactic SNR Candidates in the ROSAT All-Sky Survey

NASA Technical Reports Server (NTRS)

Schaudel, Daniel; Becker, Werner; Voges, Wolfgand; Reich, Wolfgang; Weisskopf, Martin; Six, N. Frank (Technical Monitor)

2001-01-01

Identified radio supernova remnants (SNRS) in the Galaxy comprise an incomplete sample of the SNR population due to various selection effects. ROSAT performed the first all-sky survey with an imaging X-ray telescope, and thus provides another window for finding SNRS and compact objects that may reside within them. Performing a search for extended X-ray sources in the ROSAT all-sky survey database about 350 objects were identified as SNR candidates in recent years. Continuing this systematic search, we have reanalyzed the ROSAT all-sky survey (BASS) data of these candidates and correlated the results with radio surveys like NVSS, ATNF, Molonglo, and Effelsberg. A further correlation with SIMBAD and NED were used for subsequent identification purpose. About 50 of the 350 candidates turned out to be likely galaxies or clusters of galaxies. We found 14 RASS sources which are very promising SNR candidates and are currently subject of further follow-up studies. We will provide the details of the identification campaign and present first results.

Reduced Disparities in Birth Rates Among Teens Aged 15-19 Years - United States, 2006-2007 and 2013-2014.

PubMed

Romero, Lisa; Pazol, Karen; Warner, Lee; Cox, Shanna; Kroelinger, Charlan; Besera, Ghenet; Brittain, Anna; Fuller, Taleria R; Koumans, Emilia; Barfield, Wanda

2016-04-29

Teen childbearing can have negative health, economic, and social consequences for mothers and their children (1) and costs the United States approximately $9.4 billion annually (2). During 1991-2014, the birth rate among teens aged 15-19 years in the United States declined 61%, from 61.8 to 24.2 births per 1,000, the lowest rate ever recorded (3). Nonetheless, in 2014, the teen birth rate remained approximately twice as high for Hispanic and non-Hispanic black (black) teens compared with non-Hispanic white (white) teens (3), and geographic and socioeconomic disparities remain (3,4), irrespective of race/ethnicity. Social determinants associated with teen childbearing (e.g., low parental educational attainment and limited opportunities for education and employment) are more common in communities with higher proportions of racial and ethnic minorities (4), contributing to the challenge of further reducing disparities in teen births. To examine trends in births for teens aged 15-19 years by race/ethnicity and geography, CDC analyzed National Vital Statistics System (NVSS) data at the national (2006-2014), state (2006-2007 and 2013-2014), and county (2013-2014) levels. To describe socioeconomic indicators previously associated with teen births, CDC analyzed data from the American Community Survey (ACS) (2010-2014). Nationally, from 2006 to 2014, the teen birth rate declined 41% overall with the largest decline occurring among Hispanics (51%), followed by blacks (44%), and whites (35%). The birth rate ratio for Hispanic teens and black teens compared with white teens declined from 2.9 to 2.2 and from 2.3 to 2.0, respectively. From 2006-2007 to 2013-2014, significant declines in teen birth rates and birth rate ratios were noted nationally and in many states. At the county level, teen birth rates for 2013-2014 ranged from 3.1 to 119.0 per 1,000 females aged 15-19 years; ACS data indicated unemployment was higher, and education attainment and family income were lower in counties with higher teen birth rates. State and county data can be used to understand disparities in teen births and implement community-level interventions that address the social and structural conditions associated with high teen birth rates.

Observed Faraday Effects in Damped Lyα Absorbers and Lyman Limit Systems: The Magnetized Environment of Galactic Building Blocks at Redshift = 2

NASA Astrophysics Data System (ADS)

Farnes, J. S.; Rudnick, L.; Gaensler, B. M.; Haverkorn, M.; O'Sullivan, S. P.; Curran, S. J.

2017-06-01

Protogalactic environments are typically identified using quasar absorption lines and can manifest as Damped Lyman-alpha Absorbers (DLAs) and Lyman Limit Systems (LLSs). We use radio observations of Faraday effects to test whether these galactic building blocks host a magnetized medium, by combining DLA and LLS detections with 1.4 GHz polarization data from the NRAO VLA Sky Survey (NVSS). We obtain a control, a DLA, and an LLS sample consisting of 114, 19, and 27 lines of sight, respectively. Using a Bayesian framework and weakly informative priors, we are unable to detect either coherent or random magnetic fields in DLAs: the regular coherent fields must be ≤slant 2.8 μG, and the lack of depolarization suggests the weakly magnetized gas in DLAs is non-turbulent and quiescent. However, we find a mild suggestive indication that LLSs have coherent magnetic fields, with a 71.5% probability that LLSs have higher | {RM}| than a control, although this is sensitive to the redshift distribution. We also find a strong indication that LLSs host random magnetic fields, with a 95.5% probability that LLS lines of sight have lower polarized fractions than a control. The regular coherent fields within the LLSs must be ≤slant 2.4 μG, and the magnetized gas must be highly turbulent with a typical turbulent length scale on the order of ≈5-20 pc. Our results are consistent with the standard dynamo paradigm, whereby magnetism in protogalaxies increases in coherence over cosmic time, and with a hierarchical galaxy formation scenario, with the DLAs and LLSs exploring different stages of magnetic field evolution in galaxies.

Removal of two large-scale cosmic microwave background anomalies after subtraction of the integrated Sachs-Wolfe effect

NASA Astrophysics Data System (ADS)

Rassat, A.; Starck, J.-L.; Dupé, F.-X.

2013-09-01

Context. Although there is currently a debate over the significance of the claimed large-scale anomalies in the cosmic microwave background (CMB), their existence is not totally dismissed. In parallel to the debate over their statistical significance, recent work has also focussed on masks and secondary anisotropies as potential sources of these anomalies. Aims: In this work we investigate simultaneously the impact of the method used to account for masked regions as well as the impact of the integrated Sachs-Wolfe (ISW) effect, which is the large-scale secondary anisotropy most likely to affect the CMB anomalies. In this sense, our work is an update of previous works. Our aim is to identify trends in CMB data from different years and with different mask treatments. Methods: We reconstruct the ISW signal due to 2 Micron All-Sky Survey (2MASS) and NRAO VLA Sky Survey (NVSS) galaxies, effectively reconstructing the low-redshift ISW signal out to z ~ 1. We account for regions of missing data using the sparse inpainting technique. We test sparse inpainting of the CMB, large scale structure and ISW and find that it constitutes a bias-free reconstruction method suitable to study large-scale statistical isotropy and the ISW effect. Results: We focus on three large-scale CMB anomalies: the low quadrupole, the quadrupole/octopole alignment, and the octopole planarity. After sparse inpainting, the low quadrupole becomes more anomalous, whilst the quadrupole/octopole alignment becomes less anomalous. The significance of the low quadrupole is unchanged after subtraction of the ISW effect, while the trend amongst the CMB maps is that both the low quadrupole and the quadrupole/octopole alignment have reduced significance, yet other hypotheses remain possible as well (e.g. exotic physics). Our results also suggest that both of these anomalies may be due to the quadrupole alone. While the octopole planarity significance is reduced after inpainting and after ISW subtraction, however, we do not find that it was very anomalous to start with. In the spirit of participating in reproducible research, we make all codes and resulting products which constitute main results of this paper public here: http://www.cosmostat.org/anomaliesCMB.html

Astronomical Surveys, Catalogs, Databases, and Archives

NASA Astrophysics Data System (ADS)

Mickaelian, A. M.

2016-06-01

All-sky and large-area astronomical surveys and their cataloged data over the whole range of electromagnetic spectrum are reviewed, from γ-ray to radio, such as Fermi-GLAST and INTEGRAL in γ-ray, ROSAT, XMM and Chandra in X-ray, GALEX in UV, SDSS and several POSS I and II based catalogues (APM, MAPS, USNO, GSC) in optical range, 2MASS in NIR, WISE and AKARI IRC in MIR, IRAS and AKARI FIS in FIR, NVSS and FIRST in radio and many others, as well as most important surveys giving optical images (DSS I and II, SDSS, etc.), proper motions (Tycho, USNO, Gaia), variability (GCVS, NSVS, ASAS, Catalina, Pan-STARRS) and spectroscopic data (FBS, SBS, Case, HQS, HES, SDSS, CALIFA, GAMA). Most important astronomical databases and archives are reviewed as well, including Wide-Field Plate DataBase (WFPDB), ESO, HEASARC, IRSA and MAST archives, CDS SIMBAD, VizieR and Aladin, NED and HyperLEDA extragalactic databases, ADS and astro-ph services. They are powerful sources for many-sided efficient research using Virtual Observatory tools. Using and analysis of Big Data accumulated in astronomy lead to many new discoveries.

Improving MWA/HERA Calibration Using Extended Radio Source Models

NASA Astrophysics Data System (ADS)

Cunningham, Devin; Tasker, Nicholas; University of Washington EoR Imaging Team

2018-01-01

The formation of the first stars and galaxies in the universe is among the greatest mysteries in astrophysics. Using special purpose radio interferometers, it is possible to detect the faint 21 cm radio line emitted by neutral hydrogen in order to characterize the Epoch of Reionization (EoR) and the formation of the first stars and galaxies. We create better models of extended radio sources by reducing component number of deconvolved Murchison Widefield Array (MWA) data by up to 90%, while preserving real structure and flux information. This real structure is confirmed by comparisons to observations of the same extended radio sources from the TIFR GMRT Sky Survey (TGSS) and NRAO VLA Sky Survey (NVSS), which detect at a similar frequency range as the MWA. These sophisticated data reduction techniques not only offer improvements to the calibration of the MWA, but also hold applications for the future sky-based calibration of the Hydrogen Epoch of Reionization Array (HERA). This has the potential to reduce noise in the power spectra from these instruments, and consequently provide a deeper view into the window of EoR.

catsHTM: A Tool for Fast Accessing and Cross-matching Large Astronomical Catalogs

NASA Astrophysics Data System (ADS)

Soumagnac, Maayane T.; Ofek, Eran O.

2018-07-01

Fast access to large catalogs is required for some astronomical applications. Here we introduce the catsHTM tool, consisting of several large catalogs reformatted into HDF5-based file format, which can be downloaded and used locally. To allow fast access, the catalogs are partitioned into hierarchical triangular meshes and stored in HDF5 files. Several tools are provided to perform efficient cone searches at resolutions spanning from a few arc-seconds to degrees, within a few milliseconds time. The first released version includes the following catalogs (by alphabetical order): 2MASS, 2MASS extended sources, AKARI, APASS, Cosmos, DECaLS/DR5, FIRST, GAIA/DR1, GAIA/DR2, GALEX/DR6Plus7, HSC/v2, IPHAS/DR2, NED redshifts, NVSS, Pan-STARRS1/DR1, PTF photometric catalog, ROSAT faint source, SDSS sources, SDSS/DR14 spectroscopy, SkyMapper, Spitzer/SAGE, Spitzer/IRAC galactic center, UCAC4, UKIDSS/DR10, VST/ATLAS/DR3, VST/KiDS/DR3, WISE and XMM. We provide Python code that allows to perform cone searches, as well as MATLAB code for performing cone searches, catalog cross-matching, general searches, as well as load and create these catalogs.

Multiband Study of Radio Sources of the Rcr Catalogue with Virtual Observatory Tools

NASA Astrophysics Data System (ADS)

Zhelenkova, O. P.; Soboleva, N. S.; Majorova, E. K.; Temirova, A. V.

We present early results of our multiband study of the RATAN Cold Revised (RCR) catalogue obtained from seven cycles of the ``Cold'' survey carried with the RATAN-600 radio telescope at 7.6 cm in 1980--1999, at the declination of the SS 433 source. We used the 2MASS and LAS UKIDSS infrared surveys, the DSS-II and SDSS DR7 optical surveys, as well as the USNO-B1 and GSC-II catalogues, the VLSS, TXS, NVSS, FIRST and GB6 radio surveys to accumulate information about the sources. For radio sources that have no detectable optical candidate in optical or infrared catalogues, we additionally looked through images in several bands from the SDSS, LAS UKIDSS, DPOSS, 2MASS surveys and also used co-added frames in different bands. We reliably identified 76% of radio sources of the RCR catalogue. We used the ALADIN and SAOImage DS9 scripting capabilities, interoperability services of ALADIN and TOPCAT, and also other Virtual Observatory (VO) tools and resources, such as CASJobs, NED, Vizier, and WSA, for effective data access, visualization and analysis. Without VO tools it would have been problematic to perform our study.

A search for extended radio emission from selected compact galaxy groups

NASA Astrophysics Data System (ADS)

Nikiel-Wroczyński, B.; Urbanik, M.; Soida, M.; Beck, R.; Bomans, D. J.

2017-07-01

Context. Studies on compact galaxy groups have led to the conclusion that a plenitude of phenomena take place in between galaxies that form them. However, radio data on these objects are extremely scarce and not much is known concerning the existence and role of the magnetic field in intergalactic space. Aims: We aim to study a small sample of galaxy groups that look promising as possible sources of intergalactic magnetic fields; for example data from radio surveys suggest that most of the radio emission is due to extended, diffuse structures in and out of the galaxies. Methods: We used the Effelsberg 100 m radio telescope at 4.85 GHz and NRAO VLA Sky Survey (NVSS) data at 1.40 GHz. After subtraction of compact sources we analysed the maps searching for diffuse, intergalactic radio emission. Spectral index and magnetic field properties were derived. Results: Intergalactic magnetic fields exist in groups HCG 15 and HCG 60, whereas there are no signs of them in HCG 68. There are also hints of an intergalactic bridge in HCG 44 at 4.85 GHz. Conclusions: Intergalactic magnetic fields exist in galaxy groups and their energy density may be comparable to the thermal (X-ray) density, suggesting an important role of the magnetic field in the intra-group medium, wherever it is detected.

Radio Source Contributions to the Microwave Sky

NASA Astrophysics Data System (ADS)

Boughn, S. P.; Partridge, R. B.

2008-03-01

Cross-correlations of the Wilkinson Microwave Anisotropy Probe (WMAP) full sky K-, Ka-, Q-, V-, and W-band maps with the 1.4 GHz NVSS source count map and the HEAO I A2 2-10 keV full sky X-ray flux map are used to constrain rms fluctuations due to unresolved microwave sources in the WMAP frequency range. In the Q band (40.7 GHz), a lower limit, taking account of only those fluctuations correlated with the 1.4 GHz radio source counts and X-ray flux, corresponds to an rms Rayleigh-Jeans temperature of ˜2 μK for a solid angle of 1 deg2 assuming that the cross-correlations are dominated by clustering, and ˜1 μK if dominated by Poisson fluctuations. The correlated fluctuations at the other bands are consistent with a β = -2.1 ± 0.4 frequency spectrum. If microwave sources are distributed similarly in redshift to the radio and X-ray sources and are similarly clustered, then the implied total rms microwave fluctuations correspond to ˜5 μK. While this value should be considered no more than a plausible estimate, it is similar to that implied by the excess, small angular scale fluctuations observed in the Q band by WMAP and is consistent with estimates made by extrapolating low-frequency source counts.

Panchromatic properties of 99000 galaxies detected by SDSS, and (some by) ROSAT, GALEX, 2MASS, IRAS, GB6, FIRST, NVSS and WENSS surveys

NASA Astrophysics Data System (ADS)

Obrić, M.; Ivezić, Ž.; Best, P. N.; Lupton, R. H.; Tremonti, C.; Brinchmann, J.; Agüeros, M. A.; Knapp, G. R.; Gunn, J. E.; Rockosi, C. M.; Schlegel, D.; Finkbeiner, D.; Gaćeša, M.; Smolčić, V.; Anderson, S. F.; Voges, W.; Jurić, M.; Siverd, R. J.; Steinhardt, W.; Jagoda, A. S.; Blanton, M. R.; Schneider, D. P.

2006-08-01

We discuss the panchromatic properties of 99088 galaxies selected from the Sloan Digital Sky Survey (SDSS) Data Release 1 `main' spectroscopic sample (a flux-limited sample for 1360deg2). These galaxies are positionally matched to sources detected by ROSAT, Galaxy Evolution Explorer (GALEX), two-Micron All-Sky Survey (2MASS), Infrared Astronomical Satellite (IRAS), Green Bank GB6 survey (GB6), Faint Images of the Radio Sky at Twenty-centimetres (FIRST), NRAO VLA Sky Survey (NVSS) and Westerbork Northern Sky Survey (WENSS). The matching fraction varies from <1 per cent for ROSAT and GB6 to ~40 per cent for GALEX and 2MASS. In addition to its size, the advantages of this sample are well-controlled selection effects, faint flux limits and the wealth of measured parameters, including accurate X-ray to radio photometry, angular sizes and optical spectra. We find strong correlations between the detection fraction at other wavelengths and optical properties such as flux, colours and emission-line strengths. For example, ~2/3 of SDSS `main' galaxies classified as active galactic nucleus (AGN) using emission-line strengths are detected by 2MASS, while the corresponding fraction for star-forming galaxies (SFs) is only ~1/10. Similarly, over 90 per cent of galaxies detected by IRAS display strong emission lines in their optical spectra, compared to ~50 per cent for the whole SDSS sample. Using GALEX, SDSS and 2MASS data, we construct the ultraviolet-infrared (UV-IR) broad-band spectral energy distributions for various types of galaxies, and find that they form a nearly one-parameter family. For example, the SDSS u- and r-band data, supplemented with redshift, can be used to `predict' K-band magnitudes measured by 2MASS with an rms scatter of only 0.2mag. When a dust content estimate determined from SDSS spectra with the aid of models is also utilized, this scatter decreases to 0.1mag and can be fully accounted for by measurement uncertainties. We demonstrate that this interstellar dust content, inferred from optical SDSS spectra by Kauffmann et al., is indeed higher for galaxies detected by IRAS and that it can be used to `predict' measured IRAS 60μm flux density within a factor of 2 using only SDSS data. We also show that the position of a galaxy in the emission-line-based Baldwin-Phillips-Terlevich diagram is correlated with the optical light concentration index and u - r colour determined from the SDSS broad-band imaging data, and discuss changes in the morphology of this diagram induced by requiring detections at other wavelengths. Notably, we find that SDSS `main' galaxies detected by GALEX include a non-negligible fraction (10-30 per cent) of AGNs, and hence do not represent a clean sample of starburst galaxies. We study the IR-radio correlation and find evidence that its slope may be different for AGN and SFs and related to the Hα/Hβ line-strength ratio.

A cross-correlation study of the Fermi-LAT γ-ray diffuse extragalactic signal

DOE PAGES

Xia, Jun -Qing; Cuoco, Alessandro; Branchini, Enzo; ...

2011-09-12

In this work, starting from 21 months of data from the Fermi Large Area Telescope (LAT), we derive maps of the residual isotropic γ-ray emission, a relevant fraction of which is expected to be contributed by the extragalactic diffuse γ-ray background (EGB). We search for the auto-correlation signals in the above γ-ray maps and for the cross-correlation signal with the angular distribution of different classes of objects that trace the large-scale structure of the Universe. We compute the angular two-point auto-correlation function of the residual Fermi-LAT maps at energies E > 1 GeV, E > 3 GeV and E >more » 30 GeV well above the Galactic plane and find no significant correlation signal. This is, indeed, what is expected if the EGB were contributed by BL Lacertae (BLLacs), Flat Spectrum Radio Quasars (FSRQs) or star-forming galaxies, since, in this case, the predicted signal is very weak. Then, we search for the Integrated Sachs–Wolfe (ISW) signature by cross-correlating the Fermi-LAT maps with the 7-year Wilkinson Microwave Anisotropy Probe ( WMAP7) cosmic microwave background map. We find a cross-correlation consistent with zero, even though the expected signal is larger than that of the EGB auto-correlation. Lastly, in an attempt to constrain the nature of the γ-ray background, we cross-correlate the Fermi-LAT maps with the angular distributions of objects that may contribute to the EGB: quasi-stellar objects (QSOs) in the Sloan Digital Sky Survey Data Release 6 (SDSS-DR6) catalogue, NRAO VLA Sky Survey (NVSS) galaxies, Two Micron All Sky Survey (2MASS) galaxies and Luminous Red Galaxies (LRGs) in the SDSS catalogue. The cross-correlation is always consistent with zero, in agreement with theoretical expectations, but we find (with low statistical significance) some interesting features that may indicate that some specific classes of objects contribute to the EGB. A χ 2 analysis confirms that the correlation properties of the 21-month data do not provide strong constraints of the EGB origin. However, the results suggest that the situation will significantly improve with the 5- and 10-yr Fermi-LAT data. In future, the EGB analysis will then allow placing significant constraints on the nature of the EGB and might provide, in addition, a detection of the ISW signal.« less

A Measurement of the Millimeter Emission and the Sunyaev-zel'dovich Effect Associated with Low-frequency Radio Sources

NASA Technical Reports Server (NTRS)

Gralla, Megan B.; Crichton, Devin; Marriage, Tobias A.; Mo, Wenli; Aguirre, Paula; Addison, Graeme E.; Asboth, V.; Battaglia, Nick; Bock, James; Bond, J. Richard;

CMB-galaxy correlation in Unified Dark Matter scalar field cosmologies

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

Bertacca, Daniele; Bartolo, Nicola; Matarrese, Sabino

We present an analysis of the cross-correlation between the CMB and the large-scale structure (LSS) of the Universe in Unified Dark Matter (UDM) scalar field cosmologies. We work out the predicted cross-correlation function in UDM models, which depends on the speed of sound of the unified component, and compare it with observations from six galaxy catalogues (NVSS, HEAO, 2MASS, and SDSS main galaxies, luminous red galaxies, and quasars). We sample the value of the speed of sound and perform a likelihood analysis, finding that the UDM model is as likely as the ΛCDM, and is compatible with observations for amore » range of values of c{sub ∞} (the value of the sound speed at late times) on which structure formation depends. In particular, we obtain an upper bound of c{sub ∞}{sup 2} ≤ 0.009 at 95% confidence level, meaning that the ΛCDM model, for which c{sub ∞}{sup 2} = 0, is a good fit to the data, while the posterior probability distribution peaks at the value c{sub ∞}{sup 2} = 10{sup −4} . Finally, we study the time dependence of the deviation from ΛCDM via a tomographic analysis using a mock redshift distribution and we find that the largest deviation is for low-redshift sources, suggesting that future low-z surveys will be best suited to constrain UDM models.« less

[Applications of the hospital statistics management system].

PubMed

Zhai, Hong; Ren, Yong; Liu, Jing; Li, You-Zhang; Ma, Xiao-Long; Jiao, Tao-Tao

2008-01-01

The Hospital Statistics Management System is built on an Office Automation Platform of Shandong provincial hospital system. Its workflow, role and popedom technologies are used to standardize and optimize the management program of statistics in the total quality control of hospital statistics. The system's applications have combined the office automation platform with the statistics management in a hospital and this provides a practical example of a modern hospital statistics management model.

VizieR Online Data Catalog: Radio-loud and radio-quiet quasars sample (Gupta+, 2016)

NASA Astrophysics Data System (ADS)

Gupta, M.; Sikora, M.; Nalewajko, K.

2017-11-01

We performed matching of the FR II quasar sample of van Velzen et al. (2015, Cat. J/MNRAS/446/2985) (1108 sources) with the SDSS DR7 quasar catalogue (Schneider et al., 2010AJ....139.2360S, Cat. VII/260) (105 783 sources). We used a matching radius of 5 arcsec and obtained 899 objects. This resulting sample of FR II quasars was then matched with the sample of SDSS DR7 quasars detected by the Wide-field Infrared Survey Explorer (WISE) (Wu et al., 2012, Cat. J/AJ/144/49). This gave us 895 FR II quasars detected in the MIR band. The RQ sample with MIR data is constructed by matching the DR7 quasar catalogue (Schneider et al., 2010AJ....139.2360S, Cat. VII/260) and Wise all-sky catalogue (Wu et al., 2012, Cat. J/AJ/144/49), using a matching radius of 1 arcsec, resulting in 101 853 objects. From these we remove the 899 RL quasars matched with the catalogue by van Velzen et al. (2015, Cat. J/MNRAS/446/2985), this leaves us with 100 958 quasars. We then remove objects that were detected by the FIRST survey (Becker et al. 1995ApJ...450..559B, Cat. VIII/92), this gives us 92 648. We repeat the same process with the NVSS (Condon, Cotton & Broderick, 1998AJ....115.1693C, Cat. VIII/65) and end up with 92 445 objects. We also removed those objects that were outside the FIRST observation region. (2 data files).

From 20 cm - 1 micron: Measuring the Gas and Dust in Massive Low Surface Brightness Galaxies

NASA Astrophysics Data System (ADS)

Kearsley, E.; O'Neil, K.

2005-12-01

Archival data from the IRAS, 2MASS, NVSS, and FIRST catalogs, supplemented with new measurements of HI, are used to analyze the relationship between the relative mass of the various components of galaxies (stars, atomic hydrogen, dust, and molecular gas) using a small sample of nearby (z<0.1), massive low surface brightness galaxies. The sample is compared to three sets of published data: a large collection of radio sources from the UGC having a radio continuum intensity >2.5 mJy (Condon, Cotton, & Broderick 2002 AJ 124, 675) ; a smaller sample of low surface brightness galaxies (Galaz, et al 2002 2002 AJ 124, 1360); and a collection of NIR low surface brightness galaxies (Monnier-Ragaigne, et al 2002 Ap&SS 281, 145). Overall, our sample properties are similar to the comparison samples in regard to NIR color, gas, stellar, and dynamic mass ratios, etc. Based off the galaxies' q-value (determined from the FIR/1.4 GHz ratio), it appears likely that at least two of the 28 galaxies studied harbor AGN. Notably, we also find that if we naively assume the ratio of the dust and molecular gas mass relative to the mass of HI is a constant we are unable to predict the observed ratio of stellar mass to HI mass, indicating that the HI mass ratio is a poor indicator of the total baryonic mass in the studied galaxies. HI measurements obtained during this study using the Green Bank Telescope also provide a correction to the velocity of UGC 11068.

JVLA 1.5 GHz Continuum Observation of CLASH Clusters. I. Radio Properties of the BCGs

NASA Astrophysics Data System (ADS)

Yu, Heng; Tozzi, Paolo; van Weeren, Reinout; Liuzzo, Elisabetta; Giovannini, Gabriele; Donahue, Megan; Balestra, Italo; Rosati, Piero; Aravena, Manuel

2018-02-01

We present high-resolution (∼1″), 1.5 GHz continuum observations of the brightest cluster galaxies (BCGs) of 13 CLASH (Cluster Lensing And Supernova survey with Hubble) clusters at 0.18< z< 0.69 with the Karl G. Jansky Very Large Array (JVLA). Radio emission is clearly detected and characterized for 11 BCGs, while for two of them we obtain only upper limits to their radio flux (< 0.1 mJy at 5σ confidence level). We also consider five additional clusters whose BCG is detected in FIRST or NVSS. We find radio powers in the range from 2× {10}23 to ∼ {10}26 {{W}} {{Hz}}-1 and radio spectral indices {α }1.530 (defined as the slope between 1.5 and 30 GHz) distributed from ∼ -1 to ‑0.25 around the central value < α > =-0.68. The radio emission from the BCGs is resolved in three cases (Abell 383, MACS J1931, and RX J2129), and unresolved or marginally resolved in the remaining eight cases observed with JVLA. In all the cases the BCGs are consistent with being powered by active galactic nuclei. The radio power shows a positive correlation with the BCG star formation rate, and a negative correlation with the central entropy of the surrounding intracluster medium (ICM) except in two cases (MACS J1206 and CL J1226). Finally, over the restricted range in radio power sampled by the CLASH BCGs, we observe a significant scatter between the radio power and the average mechanical power stored in the ICM cavities.

Gamma-ray blazars within the first 2 billion years

DOE PAGES

Ackermann, M.; Ajello, M.; Baldini, L.; ...

2017-02-27

Here, the detection of high-redshift (more » $$z\\,\\gt 3$$) blazars enables the study of the evolution of the most luminous relativistic jets over cosmic time. More importantly, high-redshift blazars tend to host massive black holes and can be used to constrain the space density of heavy black holes in the early universe. Here, we report the first detection with the Fermi-Large Area Telescope of five γ-ray-emitting blazars beyond z = 3.1, more distant than any blazars previously detected in γ-rays. Among these five objects, NVSS J151002+570243 is now the most distant known γ-ray-emitting blazar at z = 4.31. These objects have steeply falling γ-ray spectral energy distributions (SEDs), and those that have been observed in X-rays have a very hard X-ray spectrum, both typical of powerful blazars. Their Compton dominance (ratio of the inverse Compton to synchrotron peak luminosities) is also very large ($$\\gt 20$$). All of these properties place these objects among the most extreme members of the blazar population. Their optical spectra and the modeling of their optical-UV SEDs confirm that these objects harbor massive black holes ($${M}_{\\mathrm{BH}}\\sim {10}^{8-10}\\,{M}_{\\odot }$$). We find that, at $$z\\approx 4$$, the space density of $$\\gt {10}^{9}\\,{M}_{\\odot }$$ black holes hosted in radio-loud and radio-quiet active galactic nuclei are similar, implying that radio-loudness may play a key role in rapid black hole growth in the early universe.« less

T-RaMiSu: the Two-meter Radio Mini Survey. I. The Boötes Field

NASA Astrophysics Data System (ADS)

Williams, W. L.; Intema, H. T.; Röttgering, H. J. A.

2013-01-01

We present wide area, deep, high-resolution 153 MHz GMRT observations of the NOAO Boötes field, adding to the extensive, multi-wavelength data of this region. The observations, data reduction, and catalogue construction and description are described here. The seven pointings produced a final mosaic covering 30 square degrees with a resolution of 25″. The rms noise is 2 mJy beam-1 in the centre of the image, rising to 4-5 mJy beam-1 on the edges, with an average of 3 mJy beam-1. Seventy-five per cent of the area has an rms <4 mJy beam-1. The extracted source catalogue contains 1289 sources detected at 5σ, of which 453 are resolved. We estimate the catalogue to be 92 per cent reliable and 95 per cent complete at an integrated flux density limit of 14 mJy. The flux densities and astrometry have been corrected for systematic errors. We calculate the differential source counts, which are in good agreement with those in the literature and provide an important step forward in quantifying the source counts at these low frequencies and low flux densities. The GMRT 153 MHz sources have been matched to the 1.4 GHz NVSS and 327 MHz WENSS catalogues and spectral indices were derived. Table A.1 (Catalogue) is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/549/A55

The U.S. geological survey rass-statpac system for management and statistical reduction of geochemical data

USGS Publications Warehouse

VanTrump, G.; Miesch, A.T.

1977-01-01

RASS is an acronym for Rock Analysis Storage System and STATPAC, for Statistical Package. The RASS and STATPAC computer programs are integrated into the RASS-STATPAC system for the management and statistical reduction of geochemical data. The system, in its present form, has been in use for more than 9 yr by scores of U.S. Geological Survey geologists, geochemists, and other scientists engaged in a broad range of geologic and geochemical investigations. The principal advantage of the system is the flexibility afforded the user both in data searches and retrievals and in the manner of statistical treatment of data. The statistical programs provide for most types of statistical reduction normally used in geochemistry and petrology, but also contain bridges to other program systems for statistical processing and automatic plotting. ?? 1977.

Features of statistical dynamics in a finite system

NASA Astrophysics Data System (ADS)

Yan, Shiwei; Sakata, Fumihiko; Zhuo, Yizhong

2002-03-01

We study features of statistical dynamics in a finite Hamilton system composed of a relevant one degree of freedom coupled to an irrelevant multidegree of freedom system through a weak interaction. Special attention is paid on how the statistical dynamics changes depending on the number of degrees of freedom in the irrelevant system. It is found that the macrolevel statistical aspects are strongly related to an appearance of the microlevel chaotic motion, and a dissipation of the relevant motion is realized passing through three distinct stages: dephasing, statistical relaxation, and equilibrium regimes. It is clarified that the dynamical description and the conventional transport approach provide us with almost the same macrolevel and microlevel mechanisms only for the system with a very large number of irrelevant degrees of freedom. It is also shown that the statistical relaxation in the finite system is an anomalous diffusion and the fluctuation effects have a finite correlation time.

Features of statistical dynamics in a finite system.

PubMed

Yan, Shiwei; Sakata, Fumihiko; Zhuo, Yizhong

2002-03-01

We study features of statistical dynamics in a finite Hamilton system composed of a relevant one degree of freedom coupled to an irrelevant multidegree of freedom system through a weak interaction. Special attention is paid on how the statistical dynamics changes depending on the number of degrees of freedom in the irrelevant system. It is found that the macrolevel statistical aspects are strongly related to an appearance of the microlevel chaotic motion, and a dissipation of the relevant motion is realized passing through three distinct stages: dephasing, statistical relaxation, and equilibrium regimes. It is clarified that the dynamical description and the conventional transport approach provide us with almost the same macrolevel and microlevel mechanisms only for the system with a very large number of irrelevant degrees of freedom. It is also shown that the statistical relaxation in the finite system is an anomalous diffusion and the fluctuation effects have a finite correlation time.

Statistical principle and methodology in the NISAN system.

PubMed Central

Asano, C

1979-01-01

The NISAN system is a new interactive statistical analysis program package constructed by an organization of Japanese statisticans. The package is widely available for both statistical situations, confirmatory analysis and exploratory analysis, and is planned to obtain statistical wisdom and to choose optimal process of statistical analysis for senior statisticians. PMID:540594

Radio Jet Feedback and Star Formation in Heavily Obscured, Hyperluminous Quasars at Redshifts ˜ 0.5-3. I. ALMA Observations

NASA Astrophysics Data System (ADS)

Lonsdale, Carol J.; Lacy, M.; Kimball, A. E.; Blain, A.; Whittle, M.; Wilkes, B.; Stern, D.; Condon, J.; Kim, M.; Assef, R. J.; Tsai, C.-W.; Efstathiou, A.; Jones, S.; Eisenhardt, P.; Bridge, C.; Wu, J.; Lonsdale, Colin J.; Jones, K.; Jarrett, T.; Smith, R.

2015-11-01

We present Atacama Large Millimeter/submillimeter Array (ALMA) 870 μm (345 GHz) data for 49 high-redshift (0.47 < z < 2.85), luminous (11.7\\lt {log}({L}{{bol}}/{L}⊙ )\\lt 14.2) radio-powerful active galactic nuclei (AGNs), obtained to constrain cool dust emission from starbursts concurrent with highly obscured radiative-mode black hole (BH) accretion in massive galaxies that possess a small radio jet. The sample was selected from the Wide-field Infrared Survey Explorer with extremely steep (red) mid-infrared colors and with compact radio emission from NVSS/FIRST. Twenty-six sources are detected at 870 μm, and we find that the sample has large mid- to far-infrared luminosity ratios, consistent with a dominant and highly obscured quasar. The rest-frame 3 GHz radio powers are 24.7\\lt {log}({P}\\text{3.0 GHz}/{{{W}} {Hz}}-1)\\lt 27.3, and all sources are radio-intermediate or radio-loud. BH mass estimates are 7.7 < log(MBH/M⊙) < 10.2. The rest-frame 1-5 μm spectral energy distributions are very similar to the “Hot DOGs” (hot dust-obscured galaxies), and steeper (redder) than almost any other known extragalactic sources. ISM masses estimated for the ALMA-detected sources are 9.9 < log (MISM/M⊙) < 11.75 assuming a dust temperature of 30 K. The cool dust emission is consistent with star formation rates reaching several thousand M⊙ yr-1, depending on the assumed dust temperature, but we cannot rule out the alternative that the AGN powers all the emission in some cases. Our best constrained source has radiative transfer solutions with approximately equal contributions from an obscured AGN and a young (10-15 Myr) compact starburst.

Quantifying Deep-Imaging Limits of the VLA

NASA Astrophysics Data System (ADS)

Mayeshiba, Julia; Mayeshiba, J.; Rau, U.; Owen, F. N.

2014-01-01

The confusion limit is important to understand when conducting surveys of faint radio sources. The source count distributions derived from these surveys are indicative of the large-scale structure and evolution of the universe. The VLA’s confusion limit is not well-defined and astronomers have frequently observed below its current estimated confusion limit. Our study seeks to refine and understand these estimated values and their differences. In our study, we used sources from the center one square degree of the S3-SEX simulated sky made by Wilman et al. As a first step, we verified that our simulation matched observed trends of the confusion limit. During this process we studied the dependence of the achieved confusion limit on cleaning depth and PSF shape. We also reproduced the different limits seen by Frazer Owen in 2008 and NVSS. With this check completed, we then roughly estimated the confusion limits for the VLA’s four configurations. Our preliminary results showed that at an observing frequency of 1.4GHz , there is a confusion limit of 10µJy for the D Configuration and 5µJy for the C Configuration. These estimates are a factor of two lower than the lowest confusion limits reached by observers. While it is encouraging that our estimated confusion limits follow observed trends, more analysis of our process is needed. We could not accurately estimate confusion limits for the A and B configurations due to an artifact dominated image in the A Configuration and an estimated confusion limit that was too close to the noise level in the B Configuration. For the second part of our study we tested CASA’s source-finding algorithm. We found that as currently implemented, it has significant difficulty finding fainter sources.

Local Group dSph radio survey with ATCA (I): observations and background sources

NASA Astrophysics Data System (ADS)

Regis, Marco; Richter, Laura; Colafrancesco, Sergio; Massardi, Marcella; de Blok, W. J. G.; Profumo, Stefano; Orford, Nicola

2015-04-01

Dwarf spheroidal (dSph) galaxies are key objects in near-field cosmology, especially in connection to the study of galaxy formation and evolution at small scales. In addition, dSphs are optimal targets to investigate the nature of dark matter. However, while we begin to have deep optical photometric observations of the stellar population in these objects, little is known so far about their diffuse emission at any observing frequency, and hence on thermal and non-thermal plasma possibly residing within dSphs. In this paper, we present deep radio observations of six local dSphs performed with the Australia Telescope Compact Array (ATCA) at 16 cm wavelength. We mosaicked a region of radius of about 1 deg around three `classical' dSphs, Carina, Fornax, and Sculptor, and of about half of degree around three `ultrafaint' dSphs, BootesII, Segue2, and Hercules. The rms noise level is below 0.05 mJy for all the maps. The restoring beams full width at half-maximum ranged from 4.2 arcsec × 2.5 arcsec to 30.0 arcsec × 2.1 arcsec in the most elongated case. A catalogue including the 1392 sources detected in the six dSph fields is reported. The main properties of the background sources are discussed, with positions and fluxes of brightest objects compared with the FIRST, NVSS, and SUMSS observations of the same fields. The observed population of radio emitters in these fields is dominated by synchrotron sources. We compute the associated source number counts at 2 GHz down to fluxes of 0.25 mJy, which prove to be in agreement with AGN count models.

The Embedded Ring-like Feature and Star Formation Activities in G35.673-00.847

NASA Astrophysics Data System (ADS)

Dewangan, L. K.; Devaraj, R.; Ojha, D. K.

2018-02-01

We present a multiwavelength study to probe the star formation (SF) process in the molecular cloud linked with the G35.673-00.847 site (hereafter MCG35.6), which is traced in a velocity range of 53–62 km s‑1. Multiwavelength images reveal a semi-ring-like feature (associated with ionized gas emission) and an embedded face-on ring-like feature (without the NVSS 1.4 GHz radio emission, where 1σ ∼ 0.45 mJy beam‑1) in MCG35.6. The semi-ring-like feature is originated by the ionizing feedback from a star with spectral type B0.5V–B0V. The central region of the ring-like feature does not contain detectable ionized gas emission, indicating that the ring-like feature is unlikely to be produced by the ionizing feedback from a massive star. Several embedded Herschel clumps and young stellar objects (YSOs) are identified in MCG35.6, tracing the ongoing SF activities within the cloud. The polarization information from the Planck and GPIPS data trace the plane-of-sky magnetic field, which is oriented parallel to the major axis of the ring-like feature. At least five clumps (having M clump ∼ 740–1420 M ⊙) seem to be distributed in an almost regularly spaced manner along the ring-like feature and contain noticeable YSOs. Based on the analysis of the polarization and molecular line data, three subregions containing the clumps are found to be magnetically supercritical in the ring-like feature. Altogether, the existence of the ring-like feature and the SF activities on its edges can be explained by the magnetic field mediated process as simulated by Li & Nakamura.

Development of computer-assisted instruction application for statistical data analysis android platform as learning resource

NASA Astrophysics Data System (ADS)

Hendikawati, P.; Arifudin, R.; Zahid, M. Z.

2018-03-01

This study aims to design an android Statistics Data Analysis application that can be accessed through mobile devices to making it easier for users to access. The Statistics Data Analysis application includes various topics of basic statistical along with a parametric statistics data analysis application. The output of this application system is parametric statistics data analysis that can be used for students, lecturers, and users who need the results of statistical calculations quickly and easily understood. Android application development is created using Java programming language. The server programming language uses PHP with the Code Igniter framework, and the database used MySQL. The system development methodology used is the Waterfall methodology with the stages of analysis, design, coding, testing, and implementation and system maintenance. This statistical data analysis application is expected to support statistical lecturing activities and make students easier to understand the statistical analysis of mobile devices.

Neural Systems with Numerically Matched Input-Output Statistic: Isotonic Bivariate Statistical Modeling

PubMed Central

Fiori, Simone

2007-01-01

Bivariate statistical modeling from incomplete data is a useful statistical tool that allows to discover the model underlying two data sets when the data in the two sets do not correspond in size nor in ordering. Such situation may occur when the sizes of the two data sets do not match (i.e., there are “holes” in the data) or when the data sets have been acquired independently. Also, statistical modeling is useful when the amount of available data is enough to show relevant statistical features of the phenomenon underlying the data. We propose to tackle the problem of statistical modeling via a neural (nonlinear) system that is able to match its input-output statistic to the statistic of the available data sets. A key point of the new implementation proposed here is that it is based on look-up-table (LUT) neural systems, which guarantee a computationally advantageous way of implementing neural systems. A number of numerical experiments, performed on both synthetic and real-world data sets, illustrate the features of the proposed modeling procedure. PMID:18566641

Interfaces between statistical analysis packages and the ESRI geographic information system

NASA Technical Reports Server (NTRS)

Masuoka, E.

1980-01-01

Interfaces between ESRI's geographic information system (GIS) data files and real valued data files written to facilitate statistical analysis and display of spatially referenced multivariable data are described. An example of data analysis which utilized the GIS and the statistical analysis system is presented to illustrate the utility of combining the analytic capability of a statistical package with the data management and display features of the GIS.

Biennial Survey of Education in the United States, 1934-1936. Bulletin, 1937, No. 2. Volume II. Chapter III: Statistics of City School Systems, 1935-36

ERIC Educational Resources Information Center

Herlihy, Lester B.; Deffenbaugh, Walter S.

1938-01-01

This report presents statistics of city school systems for the school year 1935-36. prior to 1933-34 school statistics for cities included in county unit systems were estimated. Most of these cities are in Florida, Louisiana, Maryland, and West Virginia. Since the method of estimating school statistics for the cities included with the counties in…

Voice Response System Statistics Program : Operational Handbook.

DOT National Transportation Integrated Search

1980-06-01

This report documents the Voice Response System (VRS) Statistics Program developed for the preflight weather briefing VRS. It describes the VRS statistical report format and contents, the software program structure, and the program operation.

Fractional exclusion and braid statistics in one dimension: a study via dimensional reduction of Chern-Simons theory

NASA Astrophysics Data System (ADS)

Ye, Fei; Marchetti, P. A.; Su, Z. B.; Yu, L.

2017-09-01

The relation between braid and exclusion statistics is examined in one-dimensional systems, within the framework of Chern-Simons statistical transmutation in gauge invariant form with an appropriate dimensional reduction. If the matter action is anomalous, as for chiral fermions, a relation between braid and exclusion statistics can be established explicitly for both mutual and nonmutual cases. However, if it is not anomalous, the exclusion statistics of emergent low energy excitations is not necessarily connected to the braid statistics of the physical charged fields of the system. Finally, we also discuss the bosonization of one-dimensional anyonic systems through T-duality. Dedicated to the memory of Mario Tonin.

76 FR 74839 - Generalized System of Preferences (GSP): Import Statistics Relating to Competitive Need Limitations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-01

... Statistics Relating to Competitive Need Limitations AGENCY: Office of the United States Trade Representative. ACTION: Notice. SUMMARY: This notice is to inform the public of the availability of import statistics for... System of Preferences (GSP) program. These import statistics identify some articles for which the 2011...

Statistical Indicators for Religious Studies: Indicators of Level and Structure

ERIC Educational Resources Information Center

Herteliu, Claudiu; Isaic-Maniu, Alexandru

2009-01-01

Using statistic indicators as vectors of information relative to the operational status of a phenomenon, including a religious one, is unanimously accepted. By introducing a system of statistic indicators we can also analyze the interfacing areas of a phenomenon. In this context, we have elaborated a system of statistic indicators specific to the…

Derivative Free Optimization of Complex Systems with the Use of Statistical Machine Learning Models

DTIC Science & Technology

2015-09-12

AFRL-AFOSR-VA-TR-2015-0278 DERIVATIVE FREE OPTIMIZATION OF COMPLEX SYSTEMS WITH THE USE OF STATISTICAL MACHINE LEARNING MODELS Katya Scheinberg...COMPLEX SYSTEMS WITH THE USE OF STATISTICAL MACHINE LEARNING MODELS 5a.  CONTRACT NUMBER 5b.  GRANT NUMBER FA9550-11-1-0239 5c.  PROGRAM ELEMENT...developed, which has been the focus of our research. 15. SUBJECT TERMS optimization, Derivative-Free Optimization, Statistical Machine Learning 16. SECURITY

Safety Management Information Statistics (SAMIS) - 1991 Annual Report

DOT National Transportation Integrated Search

1993-02-01

The Safety Management Information Statistics 1991 Annual Report is a compilation and analysis of mass transit accident and casualty statistics reported by transit systems in the United States during 1991, under FTA's Section 15 reporting system.

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

Kogalovskii, M.R.

This paper presents a review of problems related to statistical database systems, which are wide-spread in various fields of activity. Statistical databases (SDB) are referred to as databases that consist of data and are used for statistical analysis. Topics under consideration are: SDB peculiarities, properties of data models adequate for SDB requirements, metadata functions, null-value problems, SDB compromise protection problems, stored data compression techniques, and statistical data representation means. Also examined is whether the present Database Management Systems (DBMS) satisfy the SDB requirements. Some actual research directions in SDB systems are considered.

Designing a Course in Statistics for a Learning Health Systems Training Program

ERIC Educational Resources Information Center

Samsa, Gregory P.; LeBlanc, Thomas W.; Zaas, Aimee; Howie, Lynn; Abernethy, Amy P.

2014-01-01

The core pedagogic problem considered here is how to effectively teach statistics to physicians who are engaged in a "learning health system" (LHS). This is a special case of a broader issue--namely, how to effectively teach statistics to academic physicians for whom research--and thus statistics--is a requirement for professional…

General specifications for the development of a USL NASA PC R and D statistical analysis support package

NASA Technical Reports Server (NTRS)

Dominick, Wayne D. (Editor); Bassari, Jinous; Triantafyllopoulos, Spiros

1984-01-01

The University of Southwestern Louisiana (USL) NASA PC R and D statistical analysis support package is designed to be a three-level package to allow statistical analysis for a variety of applications within the USL Data Base Management System (DBMS) contract work. The design addresses usage of the statistical facilities as a library package, as an interactive statistical analysis system, and as a batch processing package.

Generalized parastatistical systems

NASA Astrophysics Data System (ADS)

Satriawan, Mirza

2002-01-01

In the first chapter we consider systems of n-identical particles whose Hilbert spaces are invariant under the "particle permutation group" Sn, and which obey cluster decomposition. The classification of such systems by Hartle, Stolt, and Taylor in terms of state symmetry types is used, together with an additional classification based on the allowed observables in the system. We have indistinguishable (p, q)- statistics, indistinguishable infinite statistics, distinguishable (p, q)-statistics, and distinguishable infinite statistics. We refer to all of these as generalized parastatistical systems. We obtain a closed form for the grand canonical partition function (GCPF) for a non-interacting gas of particles obeying indistinguishable ( p, q)-statistics (for any p and q). As a special case we have the GCPF for the usual parabose statistics of order p, solving a 50 year old problem. Except for indistinguishable (1,1)-statistics, our results are not suitable for calculating the GCPF in the continuum energy limit. However, for indistinguishable (1,1)-statistics we calculate the continuum limit and obtain some simple thermodynamic results. In particular, we show that a system of free particles in any spatial dimension d ≥ 2 that obeys indistinguishable (1,1)-statistics will exhibit Bose-like condensation. In the second chapter we consider systems similar to those in the first chapter, but now assuming that the GCPF factorizes so that we obtain an extensive system. It turns out that having such an extensive GCPF is equivalent to the factorization of the counting function, and also to the factorization of the cluster coefficients and to the strong cluster condition on the counting coefficients. We calculate several simple thermodynamic quantities for such systems, where the results are given in terms of the cluster coefficients. In the third chapter, we give a second quantized realization of generalized parastatistical systems in the form of scalar product requirements on the Fock space F . We also give realizations of these scalar product requirements in terms of creation and annihilation operator algebras, and find that the Govorkov algebra and Greenberg's q-mutator algebra for q = 0 are the only ones from the literature that correspond to special cases of our systems.

Optimal Regulation of Structural Systems with Uncertain Parameters.

DTIC Science & Technology

1981-02-02

been addressed, in part, by Statistical Energy Analysis . Moti- vated by a concern with high frequency vibration and acoustical- structural...Parameter Systems," AFOSR-TR-79-0753 (May, 1979). 25. R. H. Lyon, Statistical Energy Analysis of Dynamical Systems: Theory and Applications, (M.I.T...Press, Cambridge, Mass., 1975). 26. E. E. Ungar, " Statistical Energy Analysis of Vibrating Systems," Trans. ASME, J. Eng. Ind. 89, 626 (1967). 139 27

Vibration Transmission through Rolling Element Bearings in Geared Rotor Systems

DTIC Science & Technology

1990-11-01

147 4.8 Concluding Remarks ........................................................... 153 V STATISTICAL ENERGY ANALYSIS ............................................ 155...and dynamic finite element techniques are used to develop the discrete vibration models while statistical energy analysis method is used for the broad...bearing system studies, geared rotor system studies, and statistical energy analysis . Each chapter is self sufficient since it is written in a

Knowing the Score. A National Review of the State and Territory Training Authority Statistical Systems. Final Report.

ERIC Educational Resources Information Center

National Centre for Vocational Education Research, Leabrook (Australia).

This report presents results of a project to produce a set of strategies to ensure the compatibility of Australian state and territory information systems with the requirements of the National Management Information and Statistics System (NATMISS) and the Australian Vocational Education and Training Management Information Statistical Standard…

[The main directions of reforming the service of medical statistics in Ukraine].

PubMed

Golubchykov, Mykhailo V; Orlova, Nataliia M; Bielikova, Inna V

2018-01-01

Introduction: Implementation of new methods of information support of managerial decision-making should ensure of the effective health system reform and create conditions for improving the quality of operational management, reasonable planning of medical care and increasing the efficiency of the use of system resources. Reforming of Medical Statistics Service of Ukraine should be considered only in the context of the reform of the entire health system. The aim: This work is an analysis of the current situation and justification of the main directions of reforming of Medical Statistics Service of Ukraine. Material and methods: In the work is used a range of methods: content analysis, bibliosemantic, systematic approach. The information base of the research became: WHO strategic and program documents, data of the Medical Statistics Center of the Ministry of Health of Ukraine. Review: The Medical Statistics Service of Ukraine has a completed and effective structure, headed by the State Institution "Medical Statistics Center of the Ministry of Health of Ukraine." This institution reports on behalf of the Ministry of Health of Ukraine to the State Statistical Service of Ukraine, the WHO European Office and other international organizations. An analysis of the current situation showed that to achieve this goal it is necessary: to improve the system of statistical indicators for an adequate assessment of the performance of health institutions, including in the economic aspect; creation of a developed medical and statistical base of administrative territories; change of existing technologies for the formation of information resources; strengthening the material-technical base of the structural units of Medical Statistics Service; improvement of the system of training and retraining of personnel for the service of medical statistics; development of international cooperation in the field of methodology and practice of medical statistics, implementation of internationally accepted methods for collecting, processing, analyzing and disseminating medical and statistical information; the creation of a medical and statistical service that adapted to the specifics of market relations in health care, flexible and sensitive to changes in international methodologies and standards. Conclusions: The data of medical statistics are the basis for taking managerial decisions by managers at all levels of health care. Reform of Medical Statistics Service of Ukraine should be considered only in the context of the reform of the entire health system. The main directions of the reform of the medical statistics service in Ukraine are: the introduction of information technologies, the improvement of the training of personnel for the service, the improvement of material and technical equipment, the maximum reuse of the data obtained, which provides for the unification of primary data and a system of indicators. The most difficult area is the formation of information funds and the introduction of modern information technologies.

[The main directions of reforming the service of medical statistics in Ukraine].

PubMed

Golubchykov, Mykhailo V; Orlova, Nataliia M; Bielikova, Inna V

Introduction: Implementation of new methods of information support of managerial decision-making should ensure of the effective health system reform and create conditions for improving the quality of operational management, reasonable planning of medical care and increasing the efficiency of the use of system resources. Reforming of Medical Statistics Service of Ukraine should be considered only in the context of the reform of the entire health system. The aim: This work is an analysis of the current situation and justification of the main directions of reforming of Medical Statistics Service of Ukraine. Material and methods: In the work is used a range of methods: content analysis, bibliosemantic, systematic approach. The information base of the research became: WHO strategic and program documents, data of the Medical Statistics Center of the Ministry of Health of Ukraine. Review: The Medical Statistics Service of Ukraine has a completed and effective structure, headed by the State Institution "Medical Statistics Center of the Ministry of Health of Ukraine." This institution reports on behalf of the Ministry of Health of Ukraine to the State Statistical Service of Ukraine, the WHO European Office and other international organizations. An analysis of the current situation showed that to achieve this goal it is necessary: to improve the system of statistical indicators for an adequate assessment of the performance of health institutions, including in the economic aspect; creation of a developed medical and statistical base of administrative territories; change of existing technologies for the formation of information resources; strengthening the material-technical base of the structural units of Medical Statistics Service; improvement of the system of training and retraining of personnel for the service of medical statistics; development of international cooperation in the field of methodology and practice of medical statistics, implementation of internationally accepted methods for collecting, processing, analyzing and disseminating medical and statistical information; the creation of a medical and statistical service that adapted to the specifics of market relations in health care, flexible and sensitive to changes in international methodologies and standards. Conclusions: The data of medical statistics are the basis for taking managerial decisions by managers at all levels of health care. Reform of Medical Statistics Service of Ukraine should be considered only in the context of the reform of the entire health system. The main directions of the reform of the medical statistics service in Ukraine are: the introduction of information technologies, the improvement of the training of personnel for the service, the improvement of material and technical equipment, the maximum reuse of the data obtained, which provides for the unification of primary data and a system of indicators. The most difficult area is the formation of information funds and the introduction of modern information technologies.

Using an Instructional LAN to Teach a Statistics Course.

ERIC Educational Resources Information Center

Barnes, J. Wesley; And Others

1988-01-01

Discusses a computer assisted learning system for engineering statistics based on personalized system of instruction methods. Describes the system's network, development, course structure, programing, and security. Lists the benefits of the system. (MVL)

Illuminating Tradespace Decisions Using Efficient Experimental Space-Filling Designs for the Engineered Resilient System Architecture

DTIC Science & Technology

2015-06-30

7. Building Statistical Metamodels using Simulation Experimental Designs ............................................... 34 7.1. Statistical Design...system design drivers across several different domain models, our methodology uses statistical metamodeling to approximate the simulations’ behavior. A...output. We build metamodels using a number of statistical methods that include stepwise regression, boosted trees, neural nets, and bootstrap forest

Illuminating Tradespace Decisions Using Efficient Experimental Space-Filling Designs for the Engineered Resilient System Architecture

DTIC Science & Technology

2015-06-01

7. Building Statistical Metamodels using Simulation Experimental Designs ............................................... 34 7.1. Statistical Design...system design drivers across several different domain models, our methodology uses statistical metamodeling to approximate the simulations’ behavior. A...output. We build metamodels using a number of statistical methods that include stepwise regression, boosted trees, neural nets, and bootstrap forest

Earth Observation System Flight Dynamics System Covariance Realism

NASA Technical Reports Server (NTRS)

Zaidi, Waqar H.; Tracewell, David

2016-01-01

This presentation applies a covariance realism technique to the National Aeronautics and Space Administration (NASA) Earth Observation System (EOS) Aqua and Aura spacecraft based on inferential statistics. The technique consists of three parts: collection calculation of definitive state estimates through orbit determination, calculation of covariance realism test statistics at each covariance propagation point, and proper assessment of those test statistics.

Atmospheric statistics for aerospace vehicle operations

NASA Technical Reports Server (NTRS)

Smith, O. E.; Batts, G. W.

1993-01-01

Statistical analysis of atmospheric variables was performed for the Shuttle Transportation System (STS) design trade studies and the establishment of launch commit criteria. Atmospheric constraint statistics have been developed for the NASP test flight, the Advanced Launch System, and the National Launch System. The concepts and analysis techniques discussed in the paper are applicable to the design and operations of any future aerospace vehicle.

[Design and implementation of online statistical analysis function in information system of air pollution and health impact monitoring].

PubMed

Lü, Yiran; Hao, Shuxin; Zhang, Guoqing; Liu, Jie; Liu, Yue; Xu, Dongqun

2018-01-01

To implement the online statistical analysis function in information system of air pollution and health impact monitoring, and obtain the data analysis information real-time. Using the descriptive statistical method as well as time-series analysis and multivariate regression analysis, SQL language and visual tools to implement online statistical analysis based on database software. Generate basic statistical tables and summary tables of air pollution exposure and health impact data online; Generate tendency charts of each data part online and proceed interaction connecting to database; Generate butting sheets which can lead to R, SAS and SPSS directly online. The information system air pollution and health impact monitoring implements the statistical analysis function online, which can provide real-time analysis result to its users.

An adaptive state of charge estimation approach for lithium-ion series-connected battery system

NASA Astrophysics Data System (ADS)

Peng, Simin; Zhu, Xuelai; Xing, Yinjiao; Shi, Hongbing; Cai, Xu; Pecht, Michael

2018-07-01

Due to the incorrect or unknown noise statistics of a battery system and its cell-to-cell variations, state of charge (SOC) estimation of a lithium-ion series-connected battery system is usually inaccurate or even divergent using model-based methods, such as extended Kalman filter (EKF) and unscented Kalman filter (UKF). To resolve this problem, an adaptive unscented Kalman filter (AUKF) based on a noise statistics estimator and a model parameter regulator is developed to accurately estimate the SOC of a series-connected battery system. An equivalent circuit model is first built based on the model parameter regulator that illustrates the influence of cell-to-cell variation on the battery system. A noise statistics estimator is then used to attain adaptively the estimated noise statistics for the AUKF when its prior noise statistics are not accurate or exactly Gaussian. The accuracy and effectiveness of the SOC estimation method is validated by comparing the developed AUKF and UKF when model and measurement statistics noises are inaccurate, respectively. Compared with the UKF and EKF, the developed method shows the highest SOC estimation accuracy.

Implementation and evaluation of an efficient secure computation system using ‘R’ for healthcare statistics

PubMed Central

Chida, Koji; Morohashi, Gembu; Fuji, Hitoshi; Magata, Fumihiko; Fujimura, Akiko; Hamada, Koki; Ikarashi, Dai; Yamamoto, Ryuichi

2014-01-01

Background and objective While the secondary use of medical data has gained attention, its adoption has been constrained due to protection of patient privacy. Making medical data secure by de-identification can be problematic, especially when the data concerns rare diseases. We require rigorous security management measures. Materials and methods Using secure computation, an approach from cryptography, our system can compute various statistics over encrypted medical records without decrypting them. An issue of secure computation is that the amount of processing time required is immense. We implemented a system that securely computes healthcare statistics from the statistical computing software ‘R’ by effectively combining secret-sharing-based secure computation with original computation. Results Testing confirmed that our system could correctly complete computation of average and unbiased variance of approximately 50 000 records of dummy insurance claim data in a little over a second. Computation including conditional expressions and/or comparison of values, for example, t test and median, could also be correctly completed in several tens of seconds to a few minutes. Discussion If medical records are simply encrypted, the risk of leaks exists because decryption is usually required during statistical analysis. Our system possesses high-level security because medical records remain in encrypted state even during statistical analysis. Also, our system can securely compute some basic statistics with conditional expressions using ‘R’ that works interactively while secure computation protocols generally require a significant amount of processing time. Conclusions We propose a secure statistical analysis system using ‘R’ for medical data that effectively integrates secret-sharing-based secure computation and original computation. PMID:24763677

Implementation and evaluation of an efficient secure computation system using 'R' for healthcare statistics.

PubMed

Chida, Koji; Morohashi, Gembu; Fuji, Hitoshi; Magata, Fumihiko; Fujimura, Akiko; Hamada, Koki; Ikarashi, Dai; Yamamoto, Ryuichi

2014-10-01

While the secondary use of medical data has gained attention, its adoption has been constrained due to protection of patient privacy. Making medical data secure by de-identification can be problematic, especially when the data concerns rare diseases. We require rigorous security management measures. Using secure computation, an approach from cryptography, our system can compute various statistics over encrypted medical records without decrypting them. An issue of secure computation is that the amount of processing time required is immense. We implemented a system that securely computes healthcare statistics from the statistical computing software 'R' by effectively combining secret-sharing-based secure computation with original computation. Testing confirmed that our system could correctly complete computation of average and unbiased variance of approximately 50,000 records of dummy insurance claim data in a little over a second. Computation including conditional expressions and/or comparison of values, for example, t test and median, could also be correctly completed in several tens of seconds to a few minutes. If medical records are simply encrypted, the risk of leaks exists because decryption is usually required during statistical analysis. Our system possesses high-level security because medical records remain in encrypted state even during statistical analysis. Also, our system can securely compute some basic statistics with conditional expressions using 'R' that works interactively while secure computation protocols generally require a significant amount of processing time. We propose a secure statistical analysis system using 'R' for medical data that effectively integrates secret-sharing-based secure computation and original computation. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Many-Body Localization and Thermalization in Quantum Statistical Mechanics

NASA Astrophysics Data System (ADS)

Nandkishore, Rahul; Huse, David A.

2015-03-01

We review some recent developments in the statistical mechanics of isolated quantum systems. We provide a brief introduction to quantum thermalization, paying particular attention to the eigenstate thermalization hypothesis (ETH) and the resulting single-eigenstate statistical mechanics. We then focus on a class of systems that fail to quantum thermalize and whose eigenstates violate the ETH: These are the many-body Anderson-localized systems; their long-time properties are not captured by the conventional ensembles of quantum statistical mechanics. These systems can forever locally remember information about their local initial conditions and are thus of interest for possibilities of storing quantum information. We discuss key features of many-body localization (MBL) and review a phenomenology of the MBL phase. Single-eigenstate statistical mechanics within the MBL phase reveal dynamically stable ordered phases, and phase transitions among them, that are invisible to equilibrium statistical mechanics and can occur at high energy and low spatial dimensionality, where equilibrium ordering is forbidden.

Static Methods in the Design of Nonlinear Automatic Control Systems,

DTIC Science & Technology

1984-06-27

227 Chapter VI. Ways of Decrease of the Number of Statistical Nodes During the Research of Nonlinear Systems...at present occupies the central place. This region of research was called the statistical dynamics of nonlinear H automatic control systems...receives further development in the numerous research of Soviet and C foreign scientists. Special role in the development of the statistical dynamics of

Statistical Features of Complex Systems ---Toward Establishing Sociological Physics---

NASA Astrophysics Data System (ADS)

Kobayashi, Naoki; Kuninaka, Hiroto; Wakita, Jun-ichi; Matsushita, Mitsugu

2011-07-01

Complex systems have recently attracted much attention, both in natural sciences and in sociological sciences. Members constituting a complex system evolve through nonlinear interactions among each other. This means that in a complex system the multiplicative experience or, so to speak, the history of each member produces its present characteristics. If attention is paid to any statistical property in any complex system, the lognormal distribution is the most natural and appropriate among the standard or ``normal'' statistics to overview the whole system. In fact, the lognormality emerges rather conspicuously when we examine, as familiar and typical examples of statistical aspects in complex systems, the nursing-care period for the aged, populations of prefectures and municipalities, and our body height and weight. Many other examples are found in nature and society. On the basis of these observations, we discuss the possibility of sociological physics.

Inventory of DOT Statistical Information Systems

DOT National Transportation Integrated Search

1983-01-01

The inventory represents an update of relevant systems described in the Transportation Statistical Reference File (TSRF), coordinated with the GAO update of Congressional Sources and Systems, and the Information Collection Budget. The inventory compi...

77 FR 62602 - Privacy Act of 1974, as Amended; System of Records Notice

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-15

... Record; (12) Statistical Reports--retrievable by names: (a) Personnel Transcript Report, (b) Class... training processes, such as the collection of statistical information on training programs, development of... systems, creating and reviewing statistics to improve the quality of services provided, or conducting debt...

Teaching Principles of Linkage and Gene Mapping with the Tomato.

ERIC Educational Resources Information Center

Hawk, James A.; And Others

1980-01-01

A three-point linkage system in tomatoes is used to explain concepts of gene mapping, linking and statistical analysis. The system is designed for teaching the effective use of statistics, and the power of genetic analysis from statistical analysis of phenotypic ratios. (Author/SA)

Social and economic sustainability of urban systems: comparative analysis of metropolitan statistical areas in Ohio, USA

EPA Science Inventory

This article presents a general and versatile methodology for assessing sustainability with Fisher Information as a function of dynamic changes in urban systems. Using robust statistical methods, six Metropolitan Statistical Areas (MSAs) in Ohio were evaluated to comparatively as...

20 CFR 634.4 - Statistical standards.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Statistical standards. 634.4 Section 634.4... System § 634.4 Statistical standards. Recipients shall agree to provide required data following the statistical standards prescribed by the Bureau of Labor Statistics for cooperative statistical programs. ...

20 CFR 634.4 - Statistical standards.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Statistical standards. 634.4 Section 634.4... System § 634.4 Statistical standards. Recipients shall agree to provide required data following the statistical standards prescribed by the Bureau of Labor Statistics for cooperative statistical programs. ...

An Investigation of the Factors Motivating Meaningful Learning of Statistics by Graduate Systems Management Students at AFIT.

DTIC Science & Technology

1987-09-01

DAC-RiB 271 AN INVESTIGATION OF THE FACTORS MOTIVATING MEANINGFUL v’ LEARNING OF STATIST (U) AIR FORCE INST OF TECH WRIGHT-PATTERSON RFB OH SCHOOL OF...Furthermore, the views expressed in the document are those of the author and do not necessarily reflect the views of the School of Systems and...MEANINGFUL LEARNING OF STATISTICS BY GRADUATE SYSTEMS MANAGEMENT STUDENTS AT AFIT THESIS Presented to the Faculty of the School of Systems and Logistics

Effective control of complex turbulent dynamical systems through statistical functionals.

PubMed

Majda, Andrew J; Qi, Di

2017-05-30

Turbulent dynamical systems characterized by both a high-dimensional phase space and a large number of instabilities are ubiquitous among complex systems in science and engineering, including climate, material, and neural science. Control of these complex systems is a grand challenge, for example, in mitigating the effects of climate change or safe design of technology with fully developed shear turbulence. Control of flows in the transition to turbulence, where there is a small dimension of instabilities about a basic mean state, is an important and successful discipline. In complex turbulent dynamical systems, it is impossible to track and control the large dimension of instabilities, which strongly interact and exchange energy, and new control strategies are needed. The goal of this paper is to propose an effective statistical control strategy for complex turbulent dynamical systems based on a recent statistical energy principle and statistical linear response theory. We illustrate the potential practical efficiency and verify this effective statistical control strategy on the 40D Lorenz 1996 model in forcing regimes with various types of fully turbulent dynamics with nearly one-half of the phase space unstable.

Military Retirement: Background and Recent Developments

DTIC Science & Technology

2014-05-28

DOD Office of the Actuary , May 2011. 3 Department of Defense, Valuation of the Military Retirement System, September 30, 2010, Office of the Actuary ...January 2012, p. 13. 4 Department of Defense, Fiscal Year 2010 DOD Statistical Report on the Military Retirement System, Office of the Actuary , May... Actuary , FY2012 DOD Statistical Report on the Military Retirement System, May 2013. Statistical documents available by fiscal year for FY2005-FY2011 at

The Fact Book: Report for the Florida College System, 2014

ERIC Educational Resources Information Center

Florida Department of Education, 2014

2014-01-01

This 2014 fact book for the Florida College System is divided into the following categories: (1) Student Information, which includes fall, annual, FTE, and program enrollment statistics, as well as credit program completion statistics; (2) Employee Information, which includes statistics regarding employee headcount by occupational activity, and…

The Fact Book: Report for the Florida College System, 2015

ERIC Educational Resources Information Center

Florida Department of Education, 2015

2015-01-01

This 2015 fact book for the Florida College System is divided into the following categories: (1) Student Information, which includes fall, annual, FTE, and program enrollment statistics, as well as credit program completion statistics; (2) Employee Information, which includes statistics regarding employee headcount by occupational activity, and…

The Fact Book: Report for the Florida College System, 2016

ERIC Educational Resources Information Center

Florida Department of Education, 2016

2016-01-01

This 2016 fact book for the Florida College System is divided into the following categories: (1) Student Information, which includes fall, annual, FTE, and program enrollment statistics, as well as credit program completion statistics; (2) Employee Information, which includes statistics regarding employee headcount by occupational activity and…

77 FR 18689 - Changes to Standard Numbering System, Vessel Identification System, and Boating Accident Report...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-28

... requires States to compile and send us reports, information, and statistics on casualties reported to them... data and statistical information received from the current collection to establish National... accident prevention programs; and publish accident statistics in accordance with Title 46 U.S.C. 6102...

Quantum formalism for classical statistics

NASA Astrophysics Data System (ADS)

Wetterich, C.

2018-06-01

In static classical statistical systems the problem of information transport from a boundary to the bulk finds a simple description in terms of wave functions or density matrices. While the transfer matrix formalism is a type of Heisenberg picture for this problem, we develop here the associated Schrödinger picture that keeps track of the local probabilistic information. The transport of the probabilistic information between neighboring hypersurfaces obeys a linear evolution equation, and therefore the superposition principle for the possible solutions. Operators are associated to local observables, with rules for the computation of expectation values similar to quantum mechanics. We discuss how non-commutativity naturally arises in this setting. Also other features characteristic of quantum mechanics, such as complex structure, change of basis or symmetry transformations, can be found in classical statistics once formulated in terms of wave functions or density matrices. We construct for every quantum system an equivalent classical statistical system, such that time in quantum mechanics corresponds to the location of hypersurfaces in the classical probabilistic ensemble. For suitable choices of local observables in the classical statistical system one can, in principle, compute all expectation values and correlations of observables in the quantum system from the local probabilistic information of the associated classical statistical system. Realizing a static memory material as a quantum simulator for a given quantum system is not a matter of principle, but rather of practical simplicity.

Statistically accurate low-order models for uncertainty quantification in turbulent dynamical systems.

PubMed

Sapsis, Themistoklis P; Majda, Andrew J

2013-08-20

A framework for low-order predictive statistical modeling and uncertainty quantification in turbulent dynamical systems is developed here. These reduced-order, modified quasilinear Gaussian (ROMQG) algorithms apply to turbulent dynamical systems in which there is significant linear instability or linear nonnormal dynamics in the unperturbed system and energy-conserving nonlinear interactions that transfer energy from the unstable modes to the stable modes where dissipation occurs, resulting in a statistical steady state; such turbulent dynamical systems are ubiquitous in geophysical and engineering turbulence. The ROMQG method involves constructing a low-order, nonlinear, dynamical system for the mean and covariance statistics in the reduced subspace that has the unperturbed statistics as a stable fixed point and optimally incorporates the indirect effect of non-Gaussian third-order statistics for the unperturbed system in a systematic calibration stage. This calibration procedure is achieved through information involving only the mean and covariance statistics for the unperturbed equilibrium. The performance of the ROMQG algorithm is assessed on two stringent test cases: the 40-mode Lorenz 96 model mimicking midlatitude atmospheric turbulence and two-layer baroclinic models for high-latitude ocean turbulence with over 125,000 degrees of freedom. In the Lorenz 96 model, the ROMQG algorithm with just a single mode captures the transient response to random or deterministic forcing. For the baroclinic ocean turbulence models, the inexpensive ROMQG algorithm with 252 modes, less than 0.2% of the total, captures the nonlinear response of the energy, the heat flux, and even the one-dimensional energy and heat flux spectra.

Nonlinear wave chaos: statistics of second harmonic fields.

PubMed

Zhou, Min; Ott, Edward; Antonsen, Thomas M; Anlage, Steven M

2017-10-01

Concepts from the field of wave chaos have been shown to successfully predict the statistical properties of linear electromagnetic fields in electrically large enclosures. The Random Coupling Model (RCM) describes these properties by incorporating both universal features described by Random Matrix Theory and the system-specific features of particular system realizations. In an effort to extend this approach to the nonlinear domain, we add an active nonlinear frequency-doubling circuit to an otherwise linear wave chaotic system, and we measure the statistical properties of the resulting second harmonic fields. We develop an RCM-based model of this system as two linear chaotic cavities coupled by means of a nonlinear transfer function. The harmonic field strengths are predicted to be the product of two statistical quantities and the nonlinearity characteristics. Statistical results from measurement-based calculation, RCM-based simulation, and direct experimental measurements are compared and show good agreement over many decades of power.

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

NASA Technical Reports Server (NTRS)

He, Yuning; Davies, Misty Dawn

2014-01-01

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

Statistical Thermodynamics and Microscale Thermophysics

NASA Astrophysics Data System (ADS)

Carey, Van P.

1999-08-01

Many exciting new developments in microscale engineering are based on the application of traditional principles of statistical thermodynamics. In this text Van Carey offers a modern view of thermodynamics, interweaving classical and statistical thermodynamic principles and applying them to current engineering systems. He begins with coverage of microscale energy storage mechanisms from a quantum mechanics perspective and then develops the fundamental elements of classical and statistical thermodynamics. Subsequent chapters discuss applications of equilibrium statistical thermodynamics to solid, liquid, and gas phase systems. The remainder of the book is devoted to nonequilibrium thermodynamics of transport phenomena and to nonequilibrium effects and noncontinuum behavior at the microscale. Although the text emphasizes mathematical development, Carey includes many examples and exercises to illustrate how the theoretical concepts are applied to systems of scientific and engineering interest. In the process he offers a fresh view of statistical thermodynamics for advanced undergraduate and graduate students, as well as practitioners, in mechanical, chemical, and materials engineering.

TRANSIT TIMING OBSERVATIONS FROM KEPLER. VI. POTENTIALLY INTERESTING CANDIDATE SYSTEMS FROM FOURIER-BASED STATISTICAL TESTS

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

Steffen, Jason H.; Ford, Eric B.; Rowe, Jason F.

2012-09-10

We analyze the deviations of transit times from a linear ephemeris for the Kepler Objects of Interest (KOI) through quarter six of science data. We conduct two statistical tests for all KOIs and a related statistical test for all pairs of KOIs in multi-transiting systems. These tests identify several systems which show potentially interesting transit timing variations (TTVs). Strong TTV systems have been valuable for the confirmation of planets and their mass measurements. Many of the systems identified in this study should prove fruitful for detailed TTV studies.

Transit Timing Observations from Kepler: VII. Potentially interesting candidate systems from Fourier-based statistical tests

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

Steffen, Jason H.; /Fermilab; Ford, Eric B.

2012-01-01

We analyze the deviations of transit times from a linear ephemeris for the Kepler Objects of Interest (KOI) through Quarter six (Q6) of science data. We conduct two statistical tests for all KOIs and a related statistical test for all pairs of KOIs in multi-transiting systems. These tests identify several systems which show potentially interesting transit timing variations (TTVs). Strong TTV systems have been valuable for the confirmation of planets and their mass measurements. Many of the systems identified in this study should prove fruitful for detailed TTV studies.

Statistical Approach To Extraction Of Texture In SAR

NASA Technical Reports Server (NTRS)

Rignot, Eric J.; Kwok, Ronald

1992-01-01

Improved statistical method of extraction of textural features in synthetic-aperture-radar (SAR) images takes account of effects of scheme used to sample raw SAR data, system noise, resolution of radar equipment, and speckle. Treatment of speckle incorporated into overall statistical treatment of speckle, system noise, and natural variations in texture. One computes speckle auto-correlation function from system transfer function that expresses effect of radar aperature and incorporates range and azimuth resolutions.

Statistical physics of human beings in games: Controlled experiments

NASA Astrophysics Data System (ADS)

Liang, Yuan; Huang, Ji-Ping

2014-07-01

It is important to know whether the laws or phenomena in statistical physics for natural systems with non-adaptive agents still hold for social human systems with adaptive agents, because this implies whether it is possible to study or understand social human systems by using statistical physics originating from natural systems. For this purpose, we review the role of human adaptability in four kinds of specific human behaviors, namely, normal behavior, herd behavior, contrarian behavior, and hedge behavior. The approach is based on controlled experiments in the framework of market-directed resource-allocation games. The role of the controlled experiments could be at least two-fold: adopting the real human decision-making process so that the system under consideration could reflect the performance of genuine human beings; making it possible to obtain macroscopic physical properties of a human system by tuning a particular factor of the system, thus directly revealing cause and effect. As a result, both computer simulations and theoretical analyses help to show a few counterparts of some laws or phenomena in statistical physics for social human systems: two-phase phenomena or phase transitions, entropy-related phenomena, and a non-equilibrium steady state. This review highlights the role of human adaptability in these counterparts, and makes it possible to study or understand some particular social human systems by means of statistical physics coming from natural systems.

Quality Space and Launch Requirements, Addendum to AS9100C

DTIC Science & Technology

2015-05-08

45 8.9.1 Statistical Process Control (SPC) .......................................................................... 45...SMC Space and Missile Systems Center SME Subject Matter Expert SOW Statement of Work SPC Statistical Process Control SPO System Program Office SRP...occur without any individual data exceeding the control limits. Control limits are developed using standard statistical methods or other approved

21 CFR 820.250 - Statistical techniques.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Statistical techniques. 820.250 Section 820.250...) MEDICAL DEVICES QUALITY SYSTEM REGULATION Statistical Techniques § 820.250 Statistical techniques. (a... statistical techniques required for establishing, controlling, and verifying the acceptability of process...

21 CFR 820.250 - Statistical techniques.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Statistical techniques. 820.250 Section 820.250...) MEDICAL DEVICES QUALITY SYSTEM REGULATION Statistical Techniques § 820.250 Statistical techniques. (a... statistical techniques required for establishing, controlling, and verifying the acceptability of process...

Statistics from the Operation of the Low-Level Wind Shear Alert System (LLWAS) during the Joint Airport Weather Studies (JAWS) Project.

DTIC Science & Technology

1984-12-01

AD-RI59 367 STATISTICS FROM THE OPERATION OF THE LOW-LEVEL WIND I/i SHEAR ALERT SYSTEM (L..(U) NATIONAL CENTER FOR ATOMSPHERIC RESEARCH BOULDER CO...NATIONAL BUREAU OF STANDARDS-1963A % % Oh b DOT/FAAIPM-84132 Statistics from the Operation of the Program Engineering Low-Level Wind Shear Alert System and...The Operation of The Low-Level Wind December 1984 Shear Alert System (LLWAS) During The JAWS Project: 6. Performing Organization Code An Interim Report

Visualizing Teacher Education as a Complex System: A Nested Simplex System Approach

ERIC Educational Resources Information Center

Ludlow, Larry; Ell, Fiona; Cochran-Smith, Marilyn; Newton, Avery; Trefcer, Kaitlin; Klein, Kelsey; Grudnoff, Lexie; Haigh, Mavis; Hill, Mary F.

2017-01-01

Our purpose is to provide an exploratory statistical representation of initial teacher education as a complex system comprised of dynamic influential elements. More precisely, we reveal what the system looks like for differently-positioned teacher education stakeholders based on our framework for gathering, statistically analyzing, and graphically…

Zubarev's Nonequilibrium Statistical Operator Method in the Generalized Statistics of Multiparticle Systems

NASA Astrophysics Data System (ADS)

Glushak, P. A.; Markiv, B. B.; Tokarchuk, M. V.

2018-01-01

We present a generalization of Zubarev's nonequilibrium statistical operator method based on the principle of maximum Renyi entropy. In the framework of this approach, we obtain transport equations for the basic set of parameters of the reduced description of nonequilibrium processes in a classical system of interacting particles using Liouville equations with fractional derivatives. For a classical systems of particles in a medium with a fractal structure, we obtain a non-Markovian diffusion equation with fractional spatial derivatives. For a concrete model of the frequency dependence of a memory function, we obtain generalized Kettano-type diffusion equation with the spatial and temporal fractality taken into account. We present a generalization of nonequilibrium thermofield dynamics in Zubarev's nonequilibrium statistical operator method in the framework of Renyi statistics.

Computer Automated Ultrasonic Inspection System

DTIC Science & Technology

1985-02-06

Reports 74 3.1.4 Statistical Analysis Capability 74 3.2 Nondestructive Evaluation Terminal Hardware 76 3.3 Nondestructive Evaluation Terminal Vendor...3.4.2.6 Create a Hold Tape 103 vi TABLE OF CONTENTS SECTION PAGE 3.4.3 System Status 104 3.4.4 Statistical Analysis 105 3.4.4.1 Statistical Analysis...Data Extraction 105 3.4.4.2 Statistical Analysis Report and Display Generation 106 3.4.5 Quality Assurance Reports 106 3.4.6 Nondestructive Inspection

Systems Models for Transportation Problems : Volume 1. Introducing a Systems Science for Transportation Planning.

DOT National Transportation Integrated Search

1976-03-01

This introductory portion of a system science for tranportation planning, which is based on the statistical physics of ensembles, a foundations laid on how statistical mechanics, equilibrium thermodynamics, and near equilbrium thermodynamics can be u...

Statistical inference for noisy nonlinear ecological dynamic systems.

PubMed

Wood, Simon N

2010-08-26

Chaotic ecological dynamic systems defy conventional statistical analysis. Systems with near-chaotic dynamics are little better. Such systems are almost invariably driven by endogenous dynamic processes plus demographic and environmental process noise, and are only observable with error. Their sensitivity to history means that minute changes in the driving noise realization, or the system parameters, will cause drastic changes in the system trajectory. This sensitivity is inherited and amplified by the joint probability density of the observable data and the process noise, rendering it useless as the basis for obtaining measures of statistical fit. Because the joint density is the basis for the fit measures used by all conventional statistical methods, this is a major theoretical shortcoming. The inability to make well-founded statistical inferences about biological dynamic models in the chaotic and near-chaotic regimes, other than on an ad hoc basis, leaves dynamic theory without the methods of quantitative validation that are essential tools in the rest of biological science. Here I show that this impasse can be resolved in a simple and general manner, using a method that requires only the ability to simulate the observed data on a system from the dynamic model about which inferences are required. The raw data series are reduced to phase-insensitive summary statistics, quantifying local dynamic structure and the distribution of observations. Simulation is used to obtain the mean and the covariance matrix of the statistics, given model parameters, allowing the construction of a 'synthetic likelihood' that assesses model fit. This likelihood can be explored using a straightforward Markov chain Monte Carlo sampler, but one further post-processing step returns pure likelihood-based inference. I apply the method to establish the dynamic nature of the fluctuations in Nicholson's classic blowfly experiments.

Vortex dynamics and Lagrangian statistics in a model for active turbulence.

PubMed

James, Martin; Wilczek, Michael

2018-02-14

Cellular suspensions such as dense bacterial flows exhibit a turbulence-like phase under certain conditions. We study this phenomenon of "active turbulence" statistically by using numerical tools. Following Wensink et al. (Proc. Natl. Acad. Sci. U.S.A. 109, 14308 (2012)), we model active turbulence by means of a generalized Navier-Stokes equation. Two-point velocity statistics of active turbulence, both in the Eulerian and the Lagrangian frame, is explored. We characterize the scale-dependent features of two-point statistics in this system. Furthermore, we extend this statistical study with measurements of vortex dynamics in this system. Our observations suggest that the large-scale statistics of active turbulence is close to Gaussian with sub-Gaussian tails.

Evaluating national cause-of-death statistics: principles and application to the case of China.

PubMed Central

Rao, Chalapati; Lopez, Alan D.; Yang, Gonghuan; Begg, Stephen; Ma, Jiemin

2005-01-01

Mortality statistics systems provide basic information on the levels and causes of mortality in populations. Only a third of the world's countries have complete civil registration systems that yield adequate cause-specific mortality data for health policy-making and monitoring. This paper describes the development of a set of criteria for evaluating the quality of national mortality statistics and applies them to China as an example. The criteria cover a range of structural, statistical and technical aspects of national mortality data. Little is known about cause-of-death data in China, which is home to roughly one-fifth of the world's population. These criteria were used to evaluate the utility of data from two mortality statistics systems in use in China, namely the Ministry of Health-Vital Registration (MOH-VR) system and the Disease Surveillance Point (DSP) system. We concluded that mortality registration was incomplete in both. No statistics were available for geographical subdivisions of the country to inform resource allocation or for the monitoring of health programmes. Compilation and publication of statistics is irregular in the case of the DSP, and they are not made publicly available at all by the MOH-VR. More research is required to measure the content validity of cause-of-death attribution in the two systems, especially due to the use of verbal autopsy methods in rural areas. This framework of criteria-based evaluation is recommended for the evaluation of national mortality data in developing countries to determine their utility and to guide efforts to improve their value for guiding policy. PMID:16184281

Compiling mortality statistics from civil registration systems in Viet Nam: the long road ahead.

PubMed

Rao, Chalapati; Osterberger, Brigitta; Anh, Tran Dam; MacDonald, Malcolm; Chúc, Nguyen Thi Kim; Hill, Peter S

2010-01-01

Accurate mortality statistics, needed for population health assessment, health policy and research, are best derived from data in vital registration systems. However, mortality statistics from vital registration systems are not available for several countries including Viet Nam. We used a mixed methods case study approach to assess vital registration operations in 2006 in three provinces in Viet Nam (Hòa Bình, Thùa Thiên-Hué and Bình Duong), and provide recommendations to strengthen vital registration systems in the country. For each province we developed life tables from population and mortality data compiled by sex and age group. Demographic methods were used to estimate completeness of death registration as an indicator of vital registration performance. Qualitative methods (document review, key informant interviews and focus group discussions) were used to assess administrative, technical and societal aspects of vital registration systems. Completeness of death registration was low in all three provinces. Problems were identified with the legal framework for registration of early neonatal deaths and deaths of temporary residents or migrants. The system does not conform to international standards for reporting cause of death or for recording detailed statistics by age, sex and cause of death. Capacity-building along with an intersectoral coordination committee involving the Ministries of Justice and Health and the General Statistics Office would improve the vital registration system, especially with regard to procedures for death registration. There appears to be strong political support for sentinel surveillance systems to generate reliable mortality statistics in Viet Nam.

The Higher Education System in Israel: Statistical Abstract and Analysis.

ERIC Educational Resources Information Center

Herskovic, Shlomo

This edition of a statistical abstract published every few years on the higher education system in Israel presents the most recent data available through 1990-91. The data were gathered through the cooperation of the Central Bureau of Statistics and institutions of higher education. Chapter 1 presents a summary of principal findings covering the…

Statistical Physics of Adaptation

DTIC Science & Technology

2016-08-23

Statistical Physics of Adaptation Nikolay Perunov, Robert A. Marsland, and Jeremy L. England Department of Physics , Physics of Living Systems Group...Subject Areas: Biological Physics , Complex Systems, Statistical Physics I. INTRODUCTION It has long been understood that nonequilibrium driving can...equilibrium may appear to have been specially selected for physical properties connected to their ability to absorb work from the particular driving environment

Teaching Research Methods and Statistics in eLearning Environments: Pedagogy, Practical Examples, and Possible Futures

PubMed Central

Rock, Adam J.; Coventry, William L.; Morgan, Methuen I.; Loi, Natasha M.

2016-01-01

Generally, academic psychologists are mindful of the fact that, for many students, the study of research methods and statistics is anxiety provoking (Gal et al., 1997). Given the ubiquitous and distributed nature of eLearning systems (Nof et al., 2015), teachers of research methods and statistics need to cultivate an understanding of how to effectively use eLearning tools to inspire psychology students to learn. Consequently, the aim of the present paper is to discuss critically how using eLearning systems might engage psychology students in research methods and statistics. First, we critically appraise definitions of eLearning. Second, we examine numerous important pedagogical principles associated with effectively teaching research methods and statistics using eLearning systems. Subsequently, we provide practical examples of our own eLearning-based class activities designed to engage psychology students to learn statistical concepts such as Factor Analysis and Discriminant Function Analysis. Finally, we discuss general trends in eLearning and possible futures that are pertinent to teachers of research methods and statistics in psychology. PMID:27014147

Teaching Research Methods and Statistics in eLearning Environments: Pedagogy, Practical Examples, and Possible Futures.

PubMed

Rock, Adam J; Coventry, William L; Morgan, Methuen I; Loi, Natasha M

2016-01-01

Generally, academic psychologists are mindful of the fact that, for many students, the study of research methods and statistics is anxiety provoking (Gal et al., 1997). Given the ubiquitous and distributed nature of eLearning systems (Nof et al., 2015), teachers of research methods and statistics need to cultivate an understanding of how to effectively use eLearning tools to inspire psychology students to learn. Consequently, the aim of the present paper is to discuss critically how using eLearning systems might engage psychology students in research methods and statistics. First, we critically appraise definitions of eLearning. Second, we examine numerous important pedagogical principles associated with effectively teaching research methods and statistics using eLearning systems. Subsequently, we provide practical examples of our own eLearning-based class activities designed to engage psychology students to learn statistical concepts such as Factor Analysis and Discriminant Function Analysis. Finally, we discuss general trends in eLearning and possible futures that are pertinent to teachers of research methods and statistics in psychology.

A Survey of Probabilistic Methods for Dynamical Systems with Uncertain Parameters.

DTIC Science & Technology

1986-05-01

J., "An Approach to the Theoretical Background of Statistical Energy Analysis Applied to Structural Vibration," Journ. Acoust. Soc. Amer., Vol. 69...1973, Sect. 8.3. 80. Lyon, R.H., " Statistical Energy Analysis of Dynamical Systems," M.I.T. Press, 1975. e) Late References added in Proofreading !! 81...Dowell, E.H., and Kubota, Y., "Asymptotic Modal Analysis and ’~ y C-" -165- Statistical Energy Analysis of Dynamical Systems," Journ. Appi. - Mech

Bayesian networks and statistical analysis application to analyze the diagnostic test accuracy

NASA Astrophysics Data System (ADS)

Orzechowski, P.; Makal, Jaroslaw; Onisko, A.

2005-02-01

The computer aided BPH diagnosis system based on Bayesian network is described in the paper. First result are compared to a given statistical method. Different statistical methods are used successfully in medicine for years. However, the undoubted advantages of probabilistic methods make them useful in application in newly created systems which are frequent in medicine, but do not have full and competent knowledge. The article presents advantages of the computer aided BPH diagnosis system in clinical practice for urologists.

Pitfalls of national routine death statistics for maternal mortality study.

PubMed

Saucedo, Monica; Bouvier-Colle, Marie-Hélène; Chantry, Anne A; Lamarche-Vadel, Agathe; Rey, Grégoire; Deneux-Tharaux, Catherine

2014-11-01

The lessons learned from the study of maternal deaths depend on the accuracy of data. Our objective was to assess time trends in the underestimation of maternal mortality (MM) in the national routine death statistics in France and to evaluate their current accuracy for the selection and causes of maternal deaths. National data obtained by enhanced methods in 1989, 1999, and 2007-09 were used as the gold standard to assess time trends in the underestimation of MM ratios (MMRs) in death statistics. Enhanced data and death statistics for 2007-09 were further compared by characterising false negatives (FNs) and false positives (FPs). The distribution of cause-specific MMRs, as assessed by each system, was described. Underestimation of MM in death statistics decreased from 55.6% in 1989 to 11.4% in 2007-09 (P < 0.001). In 2007-09, of 787 pregnancy-associated deaths, 254 were classified as maternal by the enhanced system and 211 by the death statistics; 34% of maternal deaths in the enhanced system were FNs in the death statistics, and 20% of maternal deaths in the death statistics were FPs. The hierarchy of causes of MM differed between the two systems. The discordances were mainly explained by the lack of precision in the drafting of death certificates by clinicians. Although the underestimation of MM in routine death statistics has decreased substantially over time, one third of maternal deaths remain unidentified, and the main causes of death are incorrectly identified in these data. Defining relevant priorities in maternal health requires the use of enhanced methods for MM study. © 2014 John Wiley & Sons Ltd.

Strategies for Reduced-Order Models in Uncertainty Quantification of Complex Turbulent Dynamical Systems

NASA Astrophysics Data System (ADS)

Qi, Di

Turbulent dynamical systems are ubiquitous in science and engineering. Uncertainty quantification (UQ) in turbulent dynamical systems is a grand challenge where the goal is to obtain statistical estimates for key physical quantities. In the development of a proper UQ scheme for systems characterized by both a high-dimensional phase space and a large number of instabilities, significant model errors compared with the true natural signal are always unavoidable due to both the imperfect understanding of the underlying physical processes and the limited computational resources available. One central issue in contemporary research is the development of a systematic methodology for reduced order models that can recover the crucial features both with model fidelity in statistical equilibrium and with model sensitivity in response to perturbations. In the first part, we discuss a general mathematical framework to construct statistically accurate reduced-order models that have skill in capturing the statistical variability in the principal directions of a general class of complex systems with quadratic nonlinearity. A systematic hierarchy of simple statistical closure schemes, which are built through new global statistical energy conservation principles combined with statistical equilibrium fidelity, are designed and tested for UQ of these problems. Second, the capacity of imperfect low-order stochastic approximations to model extreme events in a passive scalar field advected by turbulent flows is investigated. The effects in complicated flow systems are considered including strong nonlinear and non-Gaussian interactions, and much simpler and cheaper imperfect models with model error are constructed to capture the crucial statistical features in the stationary tracer field. Several mathematical ideas are introduced to improve the prediction skill of the imperfect reduced-order models. Most importantly, empirical information theory and statistical linear response theory are applied in the training phase for calibrating model errors to achieve optimal imperfect model parameters; and total statistical energy dynamics are introduced to improve the model sensitivity in the prediction phase especially when strong external perturbations are exerted. The validity of reduced-order models for predicting statistical responses and intermittency is demonstrated on a series of instructive models with increasing complexity, including the stochastic triad model, the Lorenz '96 model, and models for barotropic and baroclinic turbulence. The skillful low-order modeling methods developed here should also be useful for other applications such as efficient algorithms for data assimilation.

A statistical physics perspective on criticality in financial markets

NASA Astrophysics Data System (ADS)

Bury, Thomas

2013-11-01

Stock markets are complex systems exhibiting collective phenomena and particular features such as synchronization, fluctuations distributed as power-laws, non-random structures and similarity to neural networks. Such specific properties suggest that markets operate at a very special point. Financial markets are believed to be critical by analogy to physical systems, but little statistically founded evidence has been given. Through a data-based methodology and comparison to simulations inspired by the statistical physics of complex systems, we show that the Dow Jones and index sets are not rigorously critical. However, financial systems are closer to criticality in the crash neighborhood.

Quality Space and Launch Requirements Addendum to AS9100C

DTIC Science & Technology

2015-03-05

45 8.9.1 Statistical Process Control (SPC) .......................................................................... 45 8.9.1.1 Out of Control...Systems Center SME Subject Matter Expert SOW Statement of Work SPC Statistical Process Control SPO System Program Office SRP Standard Repair...individual data exceeding the control limits. Control limits are developed using standard statistical methods or other approved techniques and are based on

Random matrices and the New York City subway system

NASA Astrophysics Data System (ADS)

Jagannath, Aukosh; Trogdon, Thomas

2017-09-01

We analyze subway arrival times in the New York City subway system. We find regimes where the gaps between trains are well modeled by (unitarily invariant) random matrix statistics and Poisson statistics. The departure from random matrix statistics is captured by the value of the Coulomb potential along the subway route. This departure becomes more pronounced as trains make more stops.

Non-Markovian full counting statistics in quantum dot molecules

PubMed Central

Xue, Hai-Bin; Jiao, Hu-Jun; Liang, Jiu-Qing; Liu, Wu-Ming

2015-01-01

Full counting statistics of electron transport is a powerful diagnostic tool for probing the nature of quantum transport beyond what is obtainable from the average current or conductance measurement alone. In particular, the non-Markovian dynamics of quantum dot molecule plays an important role in the nonequilibrium electron tunneling processes. It is thus necessary to understand the non-Markovian full counting statistics in a quantum dot molecule. Here we study the non-Markovian full counting statistics in two typical quantum dot molecules, namely, serially coupled and side-coupled double quantum dots with high quantum coherence in a certain parameter regime. We demonstrate that the non-Markovian effect manifests itself through the quantum coherence of the quantum dot molecule system, and has a significant impact on the full counting statistics in the high quantum-coherent quantum dot molecule system, which depends on the coupling of the quantum dot molecule system with the source and drain electrodes. The results indicated that the influence of the non-Markovian effect on the full counting statistics of electron transport, which should be considered in a high quantum-coherent quantum dot molecule system, can provide a better understanding of electron transport through quantum dot molecules. PMID:25752245

Transportation statistics annual report, 2012

DOT National Transportation Integrated Search

2013-01-01

The Transportation Statistics Annual Report : describes the Nations transportation : system, the systems performance, its contributions : to the economy, and its effects on the : environment. This 17th edition of the report, : covering 2011 and...

Identification and properties of host galaxies of RCR radio sources

NASA Astrophysics Data System (ADS)

Zhelenkova, O. P.; Soboleva, N. S.; Majorova, E. K.; Temirova, A. V.

2013-01-01

FIRST and NVSS radio maps are used to cross identify the radio sources of the RCR catalog, which is based on observational data obtained in several runs of the "Cold" survey, with the SDSS and DPOSS digital optical sky surveys and the 2MASS, LAS UKIDSS, and WISE infrared surveys. Digital images in various filters and the coadded gri-band SDSS images, red and infrared DPOSS images, JHK-band UKIDSS images, and JHK-band 2MASS images are analyzed for the sources with no optical candidates found in the above catalogs. Our choice of optical candidates was based on the data on the structure of the radio source, its photometry, and spectroscopy (where available). We found reliable identifications for 86% of the radio sources; possible counterparts for 8% of the sources, and failed to find any optical counterparts for 6% of the sources because their host objects proved to be fainter than the limiting magnitude of the corresponding surveys. A little over half of all the identifications proved to be galaxies; about one quarter were quasars, and the types of the remaining objects were difficult to determine because of their faintness. A relation between the luminosity and the radioloudness index was derived and used to estimate the 1.4 and 3.94 GHz luminosities for the sources with unknown redshifts. We found 3% and 60% of all the RCR radio sources to be FRI-type objects ( L ≲ 1024 W/Hz at 1.4 GHz) and powerful FRII-type galaxies ( L ≳ 1026.5 W/Hz), respectively, whereas the rest are sources including objects of the FRI, FRII, and mixed FRI-FRII types. Unlike quasars, galaxies show a trend of decreasing luminosity with decreasing flux density. Note that identification would be quite problematic without the software and resources of the virtual observatory.

The Spectral Energy Distribution of the Earliest Phases of Massive Star Formation from the Spizter and Herschel Archives

NASA Astrophysics Data System (ADS)

Klein, Randolf; Looney, Leslie; Henning, Thomas; Chakrabarti, Sukanya; Shenoy, Sachin

2015-08-01

Infrared Dark Clouds (IRDCs) are very good candidates for the earliest phases of massive star formation, but can only be found in regions with high infrared background. We have searched for early phases among cold and massive (M>100M⊙) cloud cores by selecting cores from millimeter continuum surveys (Faundez et al. 2004, Sridharan et al. 2005, Klein et al. 2005, Beltran et al. 2006) without associations at short wavelengths. We compared the millimeter continuum peak positions with IR and radio catalogs (2MASS, MSX, IRAS, and NVSS) and excluded cores that had sources associated with the cores' peaks. We compiled a list of 173 cores in over 117 regions that are candidates for very early phases of Massive Star Formation (MSF). Now with the Spitzer and Herschel archives, these cores can be characterized further. The GLIMPSE and MIPSGAL programs alone covered 86 of these regions. The Herschel Archive adds even longer wavelengths. We are compiling this data set to construct the complete spectral energy distribution (SED) in the mid- and far-infrared with good spatial resolution and broad spectral coverage. This allow us to disentangle the complex regions and model the SED of the deeply embedded protostars/clusters.We will be presenting the IR properties of all cores and their embedded source, attempt a characterization, and order the cores in an evolutionary sequence. The resulting properties can be compared to e.g. IRDCs, a class of objects suggested to be the earliest stages of MSF. With the relative large number of cores, we can try to answer questions like: How homogeneous or diverse are our regions in terms of their evolutionary stage? Where do our embedded sources fit in the evolutionary sequence of IRDCs, hot molecular cores, ultra-compact HII regions, etc? How is the MSF shaping the environment and vice versa? Can we extrapolate to the initial conditions of MSF using our evolutionary sequence?

Updated tomographic analysis of the integrated Sachs-Wolfe effect and implications for dark energy

NASA Astrophysics Data System (ADS)

Stölzner, Benjamin; Cuoco, Alessandro; Lesgourgues, Julien; Bilicki, Maciej

2018-03-01

We derive updated constraints on the integrated Sachs-Wolfe (ISW) effect through cross-correlation of the cosmic microwave background with galaxy surveys. We improve with respect to similar previous analyses in several ways. First, we use the most recent versions of extragalactic object catalogs, SDSS DR12 photometric redshift (photo-z ) and 2MASS Photo-z data sets, as well as those employed earlier for ISW, SDSS QSO photo-z and NVSS samples. Second, we use for the first time the WISE × SuperCOSMOS catalog, which allows us to perform an all-sky analysis of the ISW up to z ˜0.4 . Third, thanks to the use of photo-z s , we separate each data set into different redshift bins, deriving the cross-correlation in each bin. This last step leads to a significant improvement in sensitivity. We remove cross-correlation between catalogs using masks which mutually exclude common regions of the sky. We use two methods to quantify the significance of the ISW effect. In the first one, we fix the cosmological model, derive linear galaxy biases of the catalogs, and then evaluate the significance of the ISW using a single parameter. In the second approach we perform a global fit of the ISW and of the galaxy biases varying the cosmological model. We find significances of the ISW in the range 4.7 - 5.0 σ thus reaching, for the first time in such an analysis, the threshold of 5 σ . Without the redshift tomography we find a significance of ˜4.0 σ , which shows the importance of the binning method. Finally we use the ISW data to infer constraints on the dark energy redshift evolution and equation of state. We find that the redshift range covered by the catalogs is still not optimal to derive strong constraints, although this goal will be likely reached using future datasets such as from Euclid, LSST, and SKA.

A Radio-Polarisation and Rotation Measure Study of the Gum Nebula and Its Environment

NASA Astrophysics Data System (ADS)

Purcell, C. R.; Gaensler, B. M.; Sun, X. H.; Carretti, E.; Bernardi, G.; Haverkorn, M.; Kesteven, M. J.; Poppi, S.; Schnitzeler, D. H. F. M.; Staveley-Smith, L.

2015-05-01

The Gum Nebula is 36°-wide shell-like emission nebula at a distance of only ˜450 pc. It has been hypothesized to be an old supernova remnant, fossil H ii region, wind-blown bubble, or combination of multiple objects. Here we investigate the magneto-ionic properties of the nebula using data from recent surveys: radio-continuum data from the NRAO VLA and S-band Parkes All Sky Surveys, and H α data from the Southern H-Alpha Sky Survey Atlas. We model the upper part of the nebula as a spherical shell of ionized gas expanding into the ambient medium. We perform a maximum-likelihood Markov chain Monte Carlo fit to the NVSS rotation measure data, using the H α data to constrain average electron density in the shell ne. Assuming a latitudinal background gradient in rotation measure, we find {{n}e}=1.3-0.4+0.4 c{{m}-3}, angular radius {{φ }outer}=22\\buildrel{\\circ}\\over{.} 7-0.1+0.1, shell thickness dr=18.5-1.4+1.5 pc, ambient magnetic field strength {{B}0}=3.9-2.2+4.9 μ G, and warm gas filling factor f=0.3-0.1+0.3. We constrain the local, small-scale (˜260 pc) pitch-angle of the ordered Galactic magnetic field to +7{}^\\circ ≲ \\wp ≲ +44{}^\\circ , which represents a significant deviation from the median field orientation on kiloparsec scales (˜-7.°2). The moderate compression factor X=6.0-2.5+5.1 at the edge of the H α shell implies that the “old supernova remnant” origin is unlikely. Our results support a model of the nebula as a H ii region around a wind-blown bubble. Analysis of depolarization in 2.3 GHz S-PASS data is consistent with this hypothesis and our best-fitting values agree well with previous studies of interstellar bubbles.

Development and Demonstration of a Statistical Data Base System for Library and Network Planning and Evaluation. Fourth Quarterly Report.

ERIC Educational Resources Information Center

Jones, Dennis; And Others

The National Center for Higher Education Management Systems (NCHEMS) has completed the development and demonstration of a library statistical data base. The data base, or management information system, was developed for administrators of public and academic libraries. The system provides administrators with a framework of information and…

Transportation statistics annual report, 2013

DOT National Transportation Integrated Search

2014-01-01

The Transportation Statistics Annual Report : describes the Nations transportation system, : the systems performance, its contributions to : the economy, and its effects on people and the : environment. This 18th edition of the report is : base...

Transportation statistics annual report, 2015

DOT National Transportation Integrated Search

2016-01-01

The Transportation Statistics Annual Report : describes the Nations transportation system, : the systems performance, its contributions to : the economy, and its effects on people and the : environment. This 20th edition of the report is : base...

What can we learn from noise? — Mesoscopic nonequilibrium statistical physics —

PubMed Central

KOBAYASHI, Kensuke

2016-01-01

Mesoscopic systems — small electric circuits working in quantum regime — offer us a unique experimental stage to explorer quantum transport in a tunable and precise way. The purpose of this Review is to show how they can contribute to statistical physics. We introduce the significance of fluctuation, or equivalently noise, as noise measurement enables us to address the fundamental aspects of a physical system. The significance of the fluctuation theorem (FT) in statistical physics is noted. We explain what information can be deduced from the current noise measurement in mesoscopic systems. As an important application of the noise measurement to statistical physics, we describe our experimental work on the current and current noise in an electron interferometer, which is the first experimental test of FT in quantum regime. Our attempt will shed new light in the research field of mesoscopic quantum statistical physics. PMID:27477456

Counting statistics for genetic switches based on effective interaction approximation

NASA Astrophysics Data System (ADS)

Ohkubo, Jun

2012-09-01

Applicability of counting statistics for a system with an infinite number of states is investigated. The counting statistics has been studied a lot for a system with a finite number of states. While it is possible to use the scheme in order to count specific transitions in a system with an infinite number of states in principle, we have non-closed equations in general. A simple genetic switch can be described by a master equation with an infinite number of states, and we use the counting statistics in order to count the number of transitions from inactive to active states in the gene. To avoid having the non-closed equations, an effective interaction approximation is employed. As a result, it is shown that the switching problem can be treated as a simple two-state model approximately, which immediately indicates that the switching obeys non-Poisson statistics.

What can we learn from noise? - Mesoscopic nonequilibrium statistical physics.

PubMed

Kobayashi, Kensuke

2016-01-01

Mesoscopic systems - small electric circuits working in quantum regime - offer us a unique experimental stage to explorer quantum transport in a tunable and precise way. The purpose of this Review is to show how they can contribute to statistical physics. We introduce the significance of fluctuation, or equivalently noise, as noise measurement enables us to address the fundamental aspects of a physical system. The significance of the fluctuation theorem (FT) in statistical physics is noted. We explain what information can be deduced from the current noise measurement in mesoscopic systems. As an important application of the noise measurement to statistical physics, we describe our experimental work on the current and current noise in an electron interferometer, which is the first experimental test of FT in quantum regime. Our attempt will shed new light in the research field of mesoscopic quantum statistical physics.

Humans make efficient use of natural image statistics when performing spatial interpolation.

PubMed

D'Antona, Anthony D; Perry, Jeffrey S; Geisler, Wilson S

2013-12-16

Visual systems learn through evolution and experience over the lifespan to exploit the statistical structure of natural images when performing visual tasks. Understanding which aspects of this statistical structure are incorporated into the human nervous system is a fundamental goal in vision science. To address this goal, we measured human ability to estimate the intensity of missing image pixels in natural images. Human estimation accuracy is compared with various simple heuristics (e.g., local mean) and with optimal observers that have nearly complete knowledge of the local statistical structure of natural images. Human estimates are more accurate than those of simple heuristics, and they match the performance of an optimal observer that knows the local statistical structure of relative intensities (contrasts). This optimal observer predicts the detailed pattern of human estimation errors and hence the results place strong constraints on the underlying neural mechanisms. However, humans do not reach the performance of an optimal observer that knows the local statistical structure of the absolute intensities, which reflect both local relative intensities and local mean intensity. As predicted from a statistical analysis of natural images, human estimation accuracy is negligibly improved by expanding the context from a local patch to the whole image. Our results demonstrate that the human visual system exploits efficiently the statistical structure of natural images.

Network Polymers Formed Under Nonideal Conditions.

DTIC Science & Technology

1986-12-01

the system or the limited ability of the statistical model to account for stochastic correlations. The viscosity of the reacting system was measured as...based on competing reactions (ring, chain) and employs equilibrium chain statistics . The work thus far has been limited to single cycle growth on an...polymerizations, because a large number of differential equations must be solved. The Makovian approach (sometimes referred to as the statistical or

Safety Management Information Statistics (SAMIS) - 1990 Annual Report.

DOT National Transportation Integrated Search

1992-04-01

The report is a compilation and analysis of mass transit accident and casualty statistics reported by transit systems in the United States during 1990, under the Federal Transit Administration's (FTA's) Section 15 reporting system.

Transportation Statistics Annual Report, 2017

DOT National Transportation Integrated Search

2018-01-01

The Transportation Statistics Annual Report describes the Nations transportation system, : the systems performance, its contributions to the economy, and its effects on people and the environment. This 22nd edition of the report is based on inf...

A comparison of two surveillance systems for deaths related to violent injury

PubMed Central

Comstock, R; Mallonee, S; Jordan, F

2005-01-01

Objective: To compare violent injury death reporting by the statewide Medical Examiner and Vital Statistics Office surveillance systems in Oklahoma. Methods: Using a standard study definition for violent injury death, the sensitivity and predictive value positive (PVP) of the Medical Examiner and Vital Statistics violent injury death reporting systems in Oklahoma in 2001 were evaluated. Results: Altogether 776 violent injury deaths were identified (violent injury death rate: 22.4 per 100 000 population) including 519 (66.9%) suicides, 248 (32.0%) homicides, and nine (1.2%) unintentional firearm deaths. The Medical Examiner system over-reported homicides and the Vital Statistics system under-reported homicides and suicides and over-reported unintentional firearm injury deaths. When compared with the standard, the Medical Examiner and Vital Statistics systems had sensitivities of 99.2% and 90.7% (respectively) and PVPs of 95.0% and 99.1% for homicide, sensitivities of 99.2% and 93.1% and PVPs of 100% and 99.0% for suicide, and sensitivities of 100% and 100% and PVPs of 100% and 31.0% for unintentional firearm deaths. Conclusions: Both the Vital Statistics and Medical Examiner systems contain valuable data and when combined can work synergistically to provide violent injury death information while also serving as quality control checks for each other. Preventable errors within both systems can be reduced by increasing training, addressing sources of human error, and expanding computer quality assurance programming. A standardized nationwide Medical Examiners' coding system and a national violent death reporting system that merges multiple public health and criminal justice datasets would enhance violent injury surveillance and prevention efforts. PMID:15691992

Effectiveness of feature and classifier algorithms in character recognition systems

NASA Astrophysics Data System (ADS)

Wilson, Charles L.

1993-04-01

At the first Census Optical Character Recognition Systems Conference, NIST generated accuracy data for more than character recognition systems. Most systems were tested on the recognition of isolated digits and upper and lower case alphabetic characters. The recognition experiments were performed on sample sizes of 58,000 digits, and 12,000 upper and lower case alphabetic characters. The algorithms used by the 26 conference participants included rule-based methods, image-based methods, statistical methods, and neural networks. The neural network methods included Multi-Layer Perceptron's, Learned Vector Quantitization, Neocognitrons, and cascaded neural networks. In this paper 11 different systems are compared using correlations between the answers of different systems, comparing the decrease in error rate as a function of confidence of recognition, and comparing the writer dependence of recognition. This comparison shows that methods that used different algorithms for feature extraction and recognition performed with very high levels of correlation. This is true for neural network systems, hybrid systems, and statistically based systems, and leads to the conclusion that neural networks have not yet demonstrated a clear superiority to more conventional statistical methods. Comparison of these results with the models of Vapnick (for estimation problems), MacKay (for Bayesian statistical models), Moody (for effective parameterization), and Boltzmann models (for information content) demonstrate that as the limits of training data variance are approached, all classifier systems have similar statistical properties. The limiting condition can only be approached for sufficiently rich feature sets because the accuracy limit is controlled by the available information content of the training set, which must pass through the feature extraction process prior to classification.

Harmonizing health information systems with information systems in other social and economic sectors.

PubMed Central

Macfarlane, Sarah B.

2005-01-01

Efforts to strengthen health information systems in low- and middle-income countries should include forging links with systems in other social and economic sectors. Governments are seeking comprehensive socioeconomic data on the basis of which to implement strategies for poverty reduction and to monitor achievement of the Millennium Development Goals. The health sector is looking to take action on the social factors that determine health outcomes. But there are duplications and inconsistencies between sectors in the collection, reporting, storage and analysis of socioeconomic data. National offices of statistics give higher priority to collection and analysis of economic than to social statistics. The Report of the Commission for Africa has estimated that an additional US$ 60 million a year is needed to improve systems to collect and analyse statistics in Africa. Some donors recognize that such systems have been weakened by numerous international demands for indicators, and have pledged support for national initiatives to strengthen statistical systems, as well as sectoral information systems such as those in health and education. Many governments are working to coordinate information systems to monitor and evaluate poverty reduction strategies. There is therefore an opportunity for the health sector to collaborate with other sectors to lever international resources to rationalize definition and measurement of indicators common to several sectors; streamline the content, frequency and timing of household surveys; and harmonize national and subnational databases that store socioeconomic data. Without long-term commitment to improve training and build career structures for statisticians and information technicians working in the health and other sectors, improvements in information and statistical systems cannot be sustained. PMID:16184278

Addressing the statistical mechanics of planet orbits in the solar system

NASA Astrophysics Data System (ADS)

Mogavero, Federico

2017-10-01

The chaotic nature of planet dynamics in the solar system suggests the relevance of a statistical approach to planetary orbits. In such a statistical description, the time-dependent position and velocity of the planets are replaced by the probability density function (PDF) of their orbital elements. It is natural to set up this kind of approach in the framework of statistical mechanics. In the present paper, I focus on the collisionless excitation of eccentricities and inclinations via gravitational interactions in a planetary system. The future planet trajectories in the solar system constitute the prototype of this kind of dynamics. I thus address the statistical mechanics of the solar system planet orbits and try to reproduce the PDFs numerically constructed by Laskar (2008, Icarus, 196, 1). I show that the microcanonical ensemble of the Laplace-Lagrange theory accurately reproduces the statistics of the giant planet orbits. To model the inner planets I then investigate the ansatz of equiprobability in the phase space constrained by the secular integrals of motion. The eccentricity and inclination PDFs of Earth and Venus are reproduced with no free parameters. Within the limitations of a stationary model, the predictions also show a reasonable agreement with Mars PDFs and that of Mercury inclination. The eccentricity of Mercury demands in contrast a deeper analysis. I finally revisit the random walk approach of Laskar to the time dependence of the inner planet PDFs. Such a statistical theory could be combined with direct numerical simulations of planet trajectories in the context of planet formation, which is likely to be a chaotic process.

National transportation statistics 2011

DOT National Transportation Integrated Search

2011-04-01

Compiled and published by the U.S. Department of Transportation's Bureau of Transportation Statistics : (BTS), National Transportation Statistics presents information on the U.S. transportation system, including : its physical components, safety reco...

National transportation statistics 2005

DOT National Transportation Integrated Search

2005-12-01

Compiled and published by the U.S. Department of Transportations Bureau of : Transportation Statistics (BTS), National Transportation Statistics 2004 presents : information on the U.S. transportation system, including its physical components, : sa...

National transportation statistics 2006

DOT National Transportation Integrated Search

2006-12-01

Compiled and published by the U.S. Department of Transportations Bureau of : Transportation Statistics (BTS), National Transportation Statistics 2006 presents : information on the U.S. transportation system, including its physical components, : sa...

National Transportation Statistics 2009

DOT National Transportation Integrated Search

2010-01-21

Compiled and published by the U.S. Department of Transportation's Bureau of Transportation Statistics (BTS), National Transportation Statistics presents information on the U.S. transportation system, including its physical components, safety record, ...

National transportation statistics 2004

DOT National Transportation Integrated Search

2005-01-01

Compiled and published by the U.S. Department of Transportations Bureau of : Transportation Statistics (BTS), National Transportation Statistics 2004 presents : information on the U.S. transportation system, including its physical components, : sa...

Transportation statistics annual report 1999

DOT National Transportation Integrated Search

1999-01-01

The Bureau of Transportation Statistics (BTS) presents the sixth : Transportation Statistics Annual Report. Mandated by Congress, the report : discusses the U.S. transportation system, including its physical components, : economic performance, safety...

National Transportation Statistics 2007

DOT National Transportation Integrated Search

2007-04-12

Compiled and published by the U.S. Department of Transportations Bureau of Transportation Statistics (BTS), National Transportation Statistics presents information on the U.S. transportation system, including its physical components, safety record...

National Transportation Statistics 2008

DOT National Transportation Integrated Search

2009-01-08

Compiled and published by the U.S. Department of Transportations Bureau of Transportation Statistics (BTS), National Transportation Statistics presents information on the U.S. transportation system, including its physical components, safety record...

National transportation statistics 2000

DOT National Transportation Integrated Search

2000-04-13

Compiled and published by the Bureau of Transportation Statistics (BTS), U.S. Department of Transportation, National Transportation Statistics 2000 presents information on the U.S. transportation system, including its physical components, safety reco...

National transportation statistics 2003

DOT National Transportation Integrated Search

2004-03-01

Compiled and published by the Bureau of Transportation Statistics (BTS), U.S. : Department of Transportation, National Transportation Statistics 2002 presents : information on the U.S. transportation system1, including its physical components, : safe...

National transportation statistics 2010

DOT National Transportation Integrated Search

2010-01-01

National Transportation Statistics presents statistics on the U.S. transportation system, including its physical components, safety record, economic performance, the human and natural environment, and national security. This is a large online documen...

National transportation statistics 2002

DOT National Transportation Integrated Search

2002-12-01

Compiled and published by the Bureau of Transportation Statistics (BTS), U.S. : Department of Transportation, National Transportation Statistics 2002 presents : information on the U.S. transportation system1, including its physical components, : safe...

National Transportation Statistics 2000

DOT National Transportation Integrated Search

2001-04-01

Compiled and published by the Bureau of Transportation Statistics (BTS), U.S. Department of Transportation, National Transportation Statistics 2000 presents information on the U.S. transportation system, including its physical components, safety reco...

Stability of knotted vortices in wave chaos

NASA Astrophysics Data System (ADS)

Taylor, Alexander; Dennis, Mark

Large scale tangles of disordered filaments occur in many diverse physical systems, from turbulent superfluids to optical volume speckle to liquid crystal phases. They can exhibit particular large scale random statistics despite very different local physics. We have previously used the topological statistics of knotting and linking to characterise the large scale tangling, using the vortices of three-dimensional wave chaos as a universal model system whose physical lengthscales are set only by the wavelength. Unlike geometrical quantities, the statistics of knotting depend strongly on the physical system and boundary conditions. Although knotting patterns characterise different systems, the topology of vortices is highly unstable to perturbation, under which they may reconnect with one another. In systems of constructed knots, these reconnections generally rapidly destroy the knot, but for vortex tangles the topological statistics must be stable. Using large scale simulations of chaotic eigenfunctions, we numerically investigate the prevalence and impact of reconnection events, and their effect on the topology of the tangle.

Statistical Analyses of Raw Material Data for MTM45-1/CF7442A-36% RW: CMH Cure Cycle

NASA Technical Reports Server (NTRS)

Coroneos, Rula; Pai, Shantaram, S.; Murthy, Pappu

2013-01-01

This report describes statistical characterization of physical properties of the composite material system MTM45-1/CF7442A, which has been tested and is currently being considered for use on spacecraft structures. This composite system is made of 6K plain weave graphite fibers in a highly toughened resin system. This report summarizes the distribution types and statistical details of the tests and the conditions for the experimental data generated. These distributions will be used in multivariate regression analyses to help determine material and design allowables for similar material systems and to establish a procedure for other material systems. Additionally, these distributions will be used in future probabilistic analyses of spacecraft structures. The specific properties that are characterized are the ultimate strength, modulus, and Poisson??s ratio by using a commercially available statistical package. Results are displayed using graphical and semigraphical methods and are included in the accompanying appendixes.

A system for classifying wood-using industries and recording statistics for automatic data processing.

Treesearch

E.W. Fobes; R.W. Rowe

1968-01-01

A system for classifying wood-using industries and recording pertinent statistics for automatic data processing is described. Forms and coding instructions for recording data of primary processing plants are included.

Quantum statistics and squeezing for a microwave-driven interacting magnon system.

PubMed

Haghshenasfard, Zahra; Cottam, Michael G

2017-02-01

Theoretical studies are reported for the statistical properties of a microwave-driven interacting magnon system. Both the magnetic dipole-dipole and the exchange interactions are included and the theory is developed for the case of parallel pumping allowing for the inclusion of the nonlinear processes due to the four-magnon interactions. The method of second quantization is used to transform the total Hamiltonian from spin operators to boson creation and annihilation operators. By using the coherent magnon state representation we have studied the magnon occupation number and the statistical behavior of the system. In particular, it is shown that the nonlinearities introduced by the parallel pumping field and the four-magnon interactions lead to non-classical quantum statistical properties of the system, such as magnon squeezing. Also control of the collapse-and-revival phenomena for the time evolution of the average magnon number is demonstrated by varying the parallel pumping amplitude and the four-magnon coupling.

Statistical Control Paradigm for Aerospace Structures Under Impulsive Disturbances

DTIC Science & Technology

2006-08-03

attitude control system with an innovative and robust statistical controller design shows significant promise for use in attitude hold mode operation...indicate that the existing attitude control system with an innovative and robust statistical controller design shows significant promise for use in...and three thrusters are for use in controlling the attitude of the satellite. Then the angular momentum of the satellite with three thrusters and a

The Shock and Vibration Digest. Volume 15. Number 1

DTIC Science & Technology

1983-01-01

acoustics The books are arranged to engineer is statistical energy analysis (SEA). This show the wealth of information that exists and the concept is...is also used for vibrating systems in pie nonlinear elements. However, for systems with a which statistical energy analysis and power flow continuous... statistical energy analysis to analyze the random nonlinear algebraic equations can be difficult. response of two identical subsystems coupled at an end

The level crossing rates and associated statistical properties of a random frequency response function

NASA Astrophysics Data System (ADS)

Langley, Robin S.

2018-03-01

This work is concerned with the statistical properties of the frequency response function of the energy of a random system. Earlier studies have considered the statistical distribution of the function at a single frequency, or alternatively the statistics of a band-average of the function. In contrast the present analysis considers the statistical fluctuations over a frequency band, and results are obtained for the mean rate at which the function crosses a specified level (or equivalently, the average number of times the level is crossed within the band). Results are also obtained for the probability of crossing a specified level at least once, the mean rate of occurrence of peaks, and the mean trough-to-peak height. The analysis is based on the assumption that the natural frequencies and mode shapes of the system have statistical properties that are governed by the Gaussian Orthogonal Ensemble (GOE), and the validity of this assumption is demonstrated by comparison with numerical simulations for a random plate. The work has application to the assessment of the performance of dynamic systems that are sensitive to random imperfections.

The effect of system nonlinearities on system noise statistics

NASA Technical Reports Server (NTRS)

Robinson, L. H., Jr.

1971-01-01

The effects are studied of nonlinearities in a baseline communications system on the system noise amplitude statistics. So that a meaningful identification of system nonlinearities can be made, the baseline system is assumed to transmit a single biphase-modulated signal through a relay satellite to the receiving equipment. The significant nonlinearities thus identified include square-law or product devices (e.g., in the carrier reference recovery loops in the receivers), bandpass limiters, and traveling wave tube amplifiers.

48 CFR 215.404-76 - Reporting profit and fee statistics.

Code of Federal Regulations, 2011 CFR

2011-10-01

... statistics. 215.404-76 Section 215.404-76 Federal Acquisition Regulations System DEFENSE ACQUISITION... Contract Pricing 215.404-76 Reporting profit and fee statistics. Follow the procedures at PGI 215.404-76 for reporting profit and fee statistics. [71 FR 69494, Dec. 1, 2006] ...

48 CFR 215.404-76 - Reporting profit and fee statistics.

Code of Federal Regulations, 2010 CFR

2010-10-01

... statistics. 215.404-76 Section 215.404-76 Federal Acquisition Regulations System DEFENSE ACQUISITION... Contract Pricing 215.404-76 Reporting profit and fee statistics. Follow the procedures at PGI 215.404-76 for reporting profit and fee statistics. [71 FR 69494, Dec. 1, 2006] ...

Response statistics of rotating shaft with non-linear elastic restoring forces by path integration

NASA Astrophysics Data System (ADS)

Gaidai, Oleg; Naess, Arvid; Dimentberg, Michael

2017-07-01

Extreme statistics of random vibrations is studied for a Jeffcott rotor under uniaxial white noise excitation. Restoring force is modelled as elastic non-linear; comparison is done with linearized restoring force to see the force non-linearity effect on the response statistics. While for the linear model analytical solutions and stability conditions are available, it is not generally the case for non-linear system except for some special cases. The statistics of non-linear case is studied by applying path integration (PI) method, which is based on the Markov property of the coupled dynamic system. The Jeffcott rotor response statistics can be obtained by solving the Fokker-Planck (FP) equation of the 4D dynamic system. An efficient implementation of PI algorithm is applied, namely fast Fourier transform (FFT) is used to simulate dynamic system additive noise. The latter allows significantly reduce computational time, compared to the classical PI. Excitation is modelled as Gaussian white noise, however any kind distributed white noise can be implemented with the same PI technique. Also multidirectional Markov noise can be modelled with PI in the same way as unidirectional. PI is accelerated by using Monte Carlo (MC) estimated joint probability density function (PDF) as initial input. Symmetry of dynamic system was utilized to afford higher mesh resolution. Both internal (rotating) and external damping are included in mechanical model of the rotor. The main advantage of using PI rather than MC is that PI offers high accuracy in the probability distribution tail. The latter is of critical importance for e.g. extreme value statistics, system reliability, and first passage probability.

Safety Management Information Statistics (SAMIS) - 1995 Annual Report

DOT National Transportation Integrated Search

1997-04-01

The Safety Management Information Statistics 1995 Annual Report is a compilation and analysis of transit accident, casualty and crime statistics reported under the Federal Transit Administration's National Transit Database Reporting by transit system...

Physics-based statistical model and simulation method of RF propagation in urban environments

DOEpatents

Pao, Hsueh-Yuan; Dvorak, Steven L.

2010-09-14

A physics-based statistical model and simulation/modeling method and system of electromagnetic wave propagation (wireless communication) in urban environments. In particular, the model is a computationally efficient close-formed parametric model of RF propagation in an urban environment which is extracted from a physics-based statistical wireless channel simulation method and system. The simulation divides the complex urban environment into a network of interconnected urban canyon waveguides which can be analyzed individually; calculates spectral coefficients of modal fields in the waveguides excited by the propagation using a database of statistical impedance boundary conditions which incorporates the complexity of building walls in the propagation model; determines statistical parameters of the calculated modal fields; and determines a parametric propagation model based on the statistical parameters of the calculated modal fields from which predictions of communications capability may be made.

Data Processing System (DPS) software with experimental design, statistical analysis and data mining developed for use in entomological research.

PubMed

Tang, Qi-Yi; Zhang, Chuan-Xi

2013-04-01

A comprehensive but simple-to-use software package called DPS (Data Processing System) has been developed to execute a range of standard numerical analyses and operations used in experimental design, statistics and data mining. This program runs on standard Windows computers. Many of the functions are specific to entomological and other biological research and are not found in standard statistical software. This paper presents applications of DPS to experimental design, statistical analysis and data mining in entomology. © 2012 The Authors Insect Science © 2012 Institute of Zoology, Chinese Academy of Sciences.

An overview of the mathematical and statistical analysis component of RICIS

NASA Technical Reports Server (NTRS)

Hallum, Cecil R.

1987-01-01

Mathematical and statistical analysis components of RICIS (Research Institute for Computing and Information Systems) can be used in the following problem areas: (1) quantification and measurement of software reliability; (2) assessment of changes in software reliability over time (reliability growth); (3) analysis of software-failure data; and (4) decision logic for whether to continue or stop testing software. Other areas of interest to NASA/JSC where mathematical and statistical analysis can be successfully employed include: math modeling of physical systems, simulation, statistical data reduction, evaluation methods, optimization, algorithm development, and mathematical methods in signal processing.

High-temperature behavior of a deformed Fermi gas obeying interpolating statistics.

PubMed

Algin, Abdullah; Senay, Mustafa

2012-04-01

An outstanding idea originally introduced by Greenberg is to investigate whether there is equivalence between intermediate statistics, which may be different from anyonic statistics, and q-deformed particle algebra. Also, a model to be studied for addressing such an idea could possibly provide us some new consequences about the interactions of particles as well as their internal structures. Motivated mainly by this idea, in this work, we consider a q-deformed Fermi gas model whose statistical properties enable us to effectively study interpolating statistics. Starting with a generalized Fermi-Dirac distribution function, we derive several thermostatistical functions of a gas of these deformed fermions in the thermodynamical limit. We study the high-temperature behavior of the system by analyzing the effects of q deformation on the most important thermostatistical characteristics of the system such as the entropy, specific heat, and equation of state. It is shown that such a deformed fermion model in two and three spatial dimensions exhibits the interpolating statistics in a specific interval of the model deformation parameter 0 < q < 1. In particular, for two and three spatial dimensions, it is found from the behavior of the third virial coefficient of the model that the deformation parameter q interpolates completely between attractive and repulsive systems, including the free boson and fermion cases. From the results obtained in this work, we conclude that such a model could provide much physical insight into some interacting theories of fermions, and could be useful to further study the particle systems with intermediate statistics.

Analysis of Variance: What Is Your Statistical Software Actually Doing?

ERIC Educational Resources Information Center

Li, Jian; Lomax, Richard G.

2011-01-01

Users assume statistical software packages produce accurate results. In this article, the authors systematically examined Statistical Package for the Social Sciences (SPSS) and Statistical Analysis System (SAS) for 3 analysis of variance (ANOVA) designs, mixed-effects ANOVA, fixed-effects analysis of covariance (ANCOVA), and nested ANOVA. For each…

77 FR 62517 - Proposed Data Collections Submitted for Public Comment and Recommendations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-15

...-based vital statistics at the national level, referred to as the U.S. National Vital Statistics System... days of this notice. Proposed Project Vital Statistics Training Application, OMB No. 0920-0217--Revision exp. 5/31/2013--National Center for Health Statistics (NCHS), Centers for Disease Control and...

48 CFR 1852.223-76 - Federal Automotive Statistical Tool Reporting.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Statistical Tool Reporting. 1852.223-76 Section 1852.223-76 Federal Acquisition Regulations System NATIONAL... Provisions and Clauses 1852.223-76 Federal Automotive Statistical Tool Reporting. As prescribed at 1823.271 and 1851.205, insert the following clause: Federal Automotive Statistical Tool Reporting (JUL 2003) If...

Efforts to improve international migration statistics: a historical perspective.

PubMed

Kraly, E P; Gnanasekaran, K S

1987-01-01

During the past decade, the international statistical community has made several efforts to develop standards for the definition, collection and publication of statistics on international migration. This article surveys the history of official initiatives to standardize international migration statistics by reviewing the recommendations of the International Statistical Institute, International Labor Organization, and the UN, and reports a recently proposed agenda for moving toward comparability among national statistical systems. Heightening awareness of the benefits of exchange and creating motivation to implement international standards requires a 3-pronged effort from the international statistical community. 1st, it is essential to continue discussion about the significance of improvement, specifically standardization, of international migration statistics. The move from theory to practice in this area requires ongoing focus by migration statisticians so that conformity to international standards itself becomes a criterion by which national statistical practices are examined and assessed. 2nd, the countries should be provided with technical documentation to support and facilitate the implementation of the recommended statistical systems. Documentation should be developed with an understanding that conformity to international standards for migration and travel statistics must be achieved within existing national statistical programs. 3rd, the call for statistical research in this area requires more efforts by the community of migration statisticians, beginning with the mobilization of bilateral and multilateral resources to undertake the preceding list of activities.

Do infants retain the statistics of a statistical learning experience? Insights from a developmental cognitive neuroscience perspective

PubMed Central

2017-01-01

Statistical structure abounds in language. Human infants show a striking capacity for using statistical learning (SL) to extract regularities in their linguistic environments, a process thought to bootstrap their knowledge of language. Critically, studies of SL test infants in the minutes immediately following familiarization, but long-term retention unfolds over hours and days, with almost no work investigating retention of SL. This creates a critical gap in the literature given that we know little about how single or multiple SL experiences translate into permanent knowledge. Furthermore, different memory systems with vastly different encoding and retention profiles emerge at different points in development, with the underlying memory system dictating the fidelity of the memory trace hours later. I describe the scant literature on retention of SL, the learning and retention properties of memory systems as they apply to SL, and the development of these memory systems. I propose that different memory systems support retention of SL in infant and adult learners, suggesting an explanation for the slow pace of natural language acquisition in infancy. I discuss the implications of developing memory systems for SL and suggest that we exercise caution in extrapolating from adult to infant properties of SL. This article is part of the themed issue ‘New frontiers for statistical learning in the cognitive sciences’. PMID:27872372

Do infants retain the statistics of a statistical learning experience? Insights from a developmental cognitive neuroscience perspective.

PubMed

Gómez, Rebecca L

2017-01-05

Statistical structure abounds in language. Human infants show a striking capacity for using statistical learning (SL) to extract regularities in their linguistic environments, a process thought to bootstrap their knowledge of language. Critically, studies of SL test infants in the minutes immediately following familiarization, but long-term retention unfolds over hours and days, with almost no work investigating retention of SL. This creates a critical gap in the literature given that we know little about how single or multiple SL experiences translate into permanent knowledge. Furthermore, different memory systems with vastly different encoding and retention profiles emerge at different points in development, with the underlying memory system dictating the fidelity of the memory trace hours later. I describe the scant literature on retention of SL, the learning and retention properties of memory systems as they apply to SL, and the development of these memory systems. I propose that different memory systems support retention of SL in infant and adult learners, suggesting an explanation for the slow pace of natural language acquisition in infancy. I discuss the implications of developing memory systems for SL and suggest that we exercise caution in extrapolating from adult to infant properties of SL.This article is part of the themed issue 'New frontiers for statistical learning in the cognitive sciences'. © 2016 The Author(s).

Developing a Campaign Plan to Target Centers of Gravity Within Economic Systems

DTIC Science & Technology

1995-05-01

Conclusion 67 CHAPTER 7: CURRENT AND FUTURE CONCERNS 69 Decision Making and Planning 69 Conclusion 72 CHAPTER 8: CONCLUSION 73 APPENDIX A: STATISTICS 80...Terminology and Statistical Tests 80 Country Analysis 84 APPENDIX B 154 BIBLIOGRAPHY 157 VITAE 162 IV LIST OF FIGURES Figure 1. Air Campaign...This project furthers the original statistical effort and adds to this a campaign planning approach (including both systems and operational level

Vibratory Response and Acoustical Radiation of a Water-Loaded, Turbulence-Excited Plate-Cavity System--Option 6

DTIC Science & Technology

1975-07-01

Statistical Energy Analysis MAJOR ASSUMPTIONS AND LIMITATIONS . Simply supported panel it contidarad to ba vibrating freely in a mode consisting of e...Shells: Statistical Energy Analysis . Modal Coupling and Nonresonant Transmission. Univ Houston, Dept Mech Eng Tech Report 21 (Aug 1970); also J...Oscillators. J. Acoust. Soc. Am., Vol. 34, No. 5 (May 1962). 14. Ungar, E.E., Fundamentals of Statistical Energy Analysis of Vibrating Systems, Tech

The Shock and Vibration Digest. Volume 13, Number 12

DTIC Science & Technology

1981-12-01

Resulting Unsteady Forces and Flow Phenomenon. Part III 26 BOOK REVIEWS STATISTICAL ENERGY ANALYSIS Chapter IV considers the problems of estimating J OF...stress, acceleration, modes. Statistical energy analysis (SEA), which is and pressure; estimations of the average system expressed in terms of random...by F.C. Nelson, SVD, 13 (8), pp 30-31 (Aug 1981) Lyons, R.H., Statistical Energy Analysis of Dynamic Systems, MIT Press, Cambridge, MA; Revieed by H

Evaluation of Louisiana's statistically based quality control and acceptance specifications for asphaltic concrete : final report.

DOT National Transportation Integrated Search

1998-09-01

In 1971, the Louisiana Department of Transportation and Development initiated a statistically based specification system for asphaltic concrete using historically generated data. A Materials Test Data (MATT) reporting system was also started to archi...

Some Dimensions of Data Quality in Statistical Systems

DOT National Transportation Integrated Search

1997-07-01

An important objective of a statistical data system is to enable users of the data to recommend (an organizations to take) rational action for solving problems or for improving quality of service of manufactured product. With this view in mind, this ...

Statistical Analysis Tools for Learning in Engineering Laboratories.

ERIC Educational Resources Information Center

Maher, Carolyn A.

1990-01-01

Described are engineering programs that have used automated data acquisition systems to implement data collection and analyze experiments. Applications include a biochemical engineering laboratory, heat transfer performance, engineering materials testing, mechanical system reliability, statistical control laboratory, thermo-fluid laboratory, and a…

A Gaussian wave packet phase-space representation of quantum canonical statistics

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

Coughtrie, David J.; Tew, David P.

2015-07-28

We present a mapping of quantum canonical statistical averages onto a phase-space average over thawed Gaussian wave-packet (GWP) parameters, which is exact for harmonic systems at all temperatures. The mapping invokes an effective potential surface, experienced by the wave packets, and a temperature-dependent phase-space integrand, to correctly transition from the GWP average at low temperature to classical statistics at high temperature. Numerical tests on weakly and strongly anharmonic model systems demonstrate that thermal averages of the system energy and geometric properties are accurate to within 1% of the exact quantum values at all temperatures.

Theoretical Aspects of the Patterns Recognition Statistical Theory Used for Developing the Diagnosis Algorithms for Complicated Technical Systems

NASA Astrophysics Data System (ADS)

Obozov, A. A.; Serpik, I. N.; Mihalchenko, G. S.; Fedyaeva, G. A.

2017-01-01

In the article, the problem of application of the pattern recognition (a relatively young area of engineering cybernetics) for analysis of complicated technical systems is examined. It is shown that the application of a statistical approach for hard distinguishable situations could be the most effective. The different recognition algorithms are based on Bayes approach, which estimates posteriori probabilities of a certain event and an assumed error. Application of the statistical approach to pattern recognition is possible for solving the problem of technical diagnosis complicated systems and particularly big powered marine diesel engines.

Statistical EMC: A new dimension electromagnetic compatibility of digital electronic systems

NASA Astrophysics Data System (ADS)

Tsaliovich, Anatoly

Electromagnetic compatibility compliance test results are used as a database for addressing three classes of electromagnetic-compatibility (EMC) related problems: statistical EMC profiles of digital electronic systems, the effect of equipment-under-test (EUT) parameters on the electromagnetic emission characteristics, and EMC measurement specifics. Open area test site (OATS) and absorber line shielded room (AR) results are compared for equipment-under-test highest radiated emissions. The suggested statistical evaluation methodology can be utilized to correlate the results of different EMC test techniques, characterize the EMC performance of electronic systems and components, and develop recommendations for electronic product optimal EMC design.

Underestimates of unintentional firearm fatalities: comparing Supplementary Homicide Report data with the National Vital Statistics System

PubMed Central

Barber, C; Hemenway, D; Hochstadt, J; Azrael, D

2002-01-01

Objective: A growing body of evidence suggests that the nation's vital statistics system undercounts unintentional firearm deaths that are not self inflicted. This issue was examined by comparing how unintentional firearm injuries identified in police Supplementary Homicide Report (SHR) data were coded in the National Vital Statistics System. Methods: National Vital Statistics System data are based on death certificates and divide firearm fatalities into six subcategories: homicide, suicide, accident, legal intervention, war operations, and undetermined. SHRs are completed by local police departments as part of the FBI's Uniform Crime Reports program. The SHR divides homicides into two categories: "murder and non-negligent manslaughter" (type A) and "negligent manslaughter" (type B). Type B shooting deaths are those that are inflicted by another person and that a police investigation determined were inflicted unintentionally, as in a child killing a playmate after mistaking a gun for a toy. In 1997, the SHR classified 168 shooting victims this way. Using probabilistic matching, 140 of these victims were linked to their death certificate records. Results: Among the 140 linked cases, 75% were recorded on the death certificate as homicides and only 23% as accidents. Conclusion: Official data from the National Vital Statistics System almost certainly undercount firearm accidents when the victim is shot by another person. PMID:12226128

Prior-to-Secondary School Course Classification System: School Codes for the Exchange of Data (SCED). NFES 2011-801

ERIC Educational Resources Information Center

National Forum on Education Statistics, 2011

2011-01-01

In this handbook, "Prior-to-Secondary School Course Classification System: School Codes for the Exchange of Data" (SCED), the National Center for Education Statistics (NCES) and the National Forum on Education Statistics have extended the existing secondary course classification system with codes and descriptions for courses offered at…

Demographic Norms for Metropolitan, Nonmetropolitan and Rural Counties. Mental Health Demographic Profile System Working Paper No. 24, July 1975.

ERIC Educational Resources Information Center

Goldsmith, Harold F.; And Others

Utilizing 1970 census statistics for metropolitan, nonmetropolitan, rural, and "all" counties, this paper presents the selected percentile values for the 130 statistics (social indicators) in the Mental Health Demographic Profile System (the MHDPS is a system which allows the delineation of residential areas with common social rank, life…

Comparing international crash statistics

DOT National Transportation Integrated Search

1999-12-01

In order to examine national developments in traffic safety, crash statistics from several of the more safety, crash statistics from several of the more United States. Data obtained from the Fatality Analysis Reporting System (FARS) and the Internati...

Management system, organizational climate and performance relationships

NASA Technical Reports Server (NTRS)

Davis, B. D.

1979-01-01

Seven aerospace firms were investigated to determine if a relationship existed among management systems, organizational climate, and organization performance. Positive relationships were found between each of these variables, but a statistically significant relationship existed only between the management system and organizational climate. The direction and amount of communication and the degree of decentralized decision-making, elements of the management system, also had a statistically significant realtionship with organization performance.

Chern-Simons Term: Theory and Applications.

NASA Astrophysics Data System (ADS)

Gupta, Kumar Sankar

1992-01-01

We investigate the quantization and applications of Chern-Simons theories to several systems of interest. Elementary canonical methods are employed for the quantization of abelian and nonabelian Chern-Simons actions using ideas from gauge theories and quantum gravity. When the spatial slice is a disc, it yields quantum states at the edge of the disc carrying a representation of the Kac-Moody algebra. We next include sources in this model and their quantum states are shown to be those of a conformal family. Vertex operators for both abelian and nonabelian sources are constructed. The regularized abelian Wilson line is proved to be a vertex operator. The spin-statistics theorem is established for Chern-Simons dynamics using purely geometrical techniques. Chern-Simons action is associated with exotic spin and statistics in 2 + 1 dimensions. We study several systems in which the Chern-Simons action affects the spin and statistics. The first class of systems we study consist of G/H models. The solitons of these models are shown to obey anyonic statistics in the presence of a Chern-Simons term. The second system deals with the effect of the Chern -Simons term in a model for high temperature superconductivity. The coefficient of the Chern-Simons term is shown to be quantized, one of its possible values giving fermionic statistics to the solitons of this model. Finally, we study a system of spinning particles interacting with 2 + 1 gravity, the latter being described by an ISO(2,1) Chern-Simons term. An effective action for the particles is obtained by integrating out the gauge fields. Next we construct operators which exchange the particles. They are shown to satisfy the braid relations. There are ambiguities in the quantization of this system which can be exploited to give anyonic statistics to the particles. We also point out that at the level of the first quantized theory, the usual spin-statistics relation need not apply to these particles.

Particle-sampling statistics in laser anemometers Sample-and-hold systems and saturable systems

NASA Technical Reports Server (NTRS)

Edwards, R. V.; Jensen, A. S.

1983-01-01

The effect of the data-processing system on the particle statistics obtained with laser anemometry of flows containing suspended particles is examined. Attention is given to the sample and hold processor, a pseudo-analog device which retains the last measurement until a new measurement is made, followed by time-averaging of the data. The second system considered features a dead time, i.e., a saturable system with a significant reset time with storage in a data buffer. It is noted that the saturable system operates independent of the particle arrival rate. The probabilities of a particle arrival in a given time period are calculated for both processing systems. It is shown that the system outputs are dependent on the mean particle flow rate, the flow correlation time, and the flow statistics, indicating that the particle density affects both systems. The results are significant for instances of good correlation between the particle density and velocity, such as occurs near the edge of a jet.

Safety Management Information Statistics (SAMIS) - 1992 Annual Report

DOT National Transportation Integrated Search

1994-06-01

This SAMIS 1992 annual report, now in its third year of publication, is a compilation and analysis of mass transit accident and casualty statistics reported by 600 transit systems in the United States under the FTA Section 15 reporting system. This r...

Key Statistics from the National Survey of Family Growth: Vasectomy

MedlinePlus

... Birth Data NCHS Key Statistics from the National Survey of Family Growth - V Listing Recommend on Facebook ... What's this? Submit Button Related Sites NCHS Listservs Surveys and Data Collection Systems Vital Statistics: Birth Data ...

Safety Management Information Statistics (SAMIS) - 1994 Annual Report

DOT National Transportation Integrated Search

1996-07-01

The Safety Management Information Statistics 1994 Annual Report is a compilation and analysis of mass transit accident and casualty statistics reported by transit systems in the United States during 1994, reported under the Federal Transit Administra...

Statistics of Shared Components in Complex Component Systems

NASA Astrophysics Data System (ADS)

Mazzolini, Andrea; Gherardi, Marco; Caselle, Michele; Cosentino Lagomarsino, Marco; Osella, Matteo

2018-04-01

Many complex systems are modular. Such systems can be represented as "component systems," i.e., sets of elementary components, such as LEGO bricks in LEGO sets. The bricks found in a LEGO set reflect a target architecture, which can be built following a set-specific list of instructions. In other component systems, instead, the underlying functional design and constraints are not obvious a priori, and their detection is often a challenge of both scientific and practical importance, requiring a clear understanding of component statistics. Importantly, some quantitative invariants appear to be common to many component systems, most notably a common broad distribution of component abundances, which often resembles the well-known Zipf's law. Such "laws" affect in a general and nontrivial way the component statistics, potentially hindering the identification of system-specific functional constraints or generative processes. Here, we specifically focus on the statistics of shared components, i.e., the distribution of the number of components shared by different system realizations, such as the common bricks found in different LEGO sets. To account for the effects of component heterogeneity, we consider a simple null model, which builds system realizations by random draws from a universe of possible components. Under general assumptions on abundance heterogeneity, we provide analytical estimates of component occurrence, which quantify exhaustively the statistics of shared components. Surprisingly, this simple null model can positively explain important features of empirical component-occurrence distributions obtained from large-scale data on bacterial genomes, LEGO sets, and book chapters. Specific architectural features and functional constraints can be detected from occurrence patterns as deviations from these null predictions, as we show for the illustrative case of the "core" genome in bacteria.

Autoregressive statistical pattern recognition algorithms for damage detection in civil structures

NASA Astrophysics Data System (ADS)

Yao, Ruigen; Pakzad, Shamim N.

2012-08-01

Statistical pattern recognition has recently emerged as a promising set of complementary methods to system identification for automatic structural damage assessment. Its essence is to use well-known concepts in statistics for boundary definition of different pattern classes, such as those for damaged and undamaged structures. In this paper, several statistical pattern recognition algorithms using autoregressive models, including statistical control charts and hypothesis testing, are reviewed as potentially competitive damage detection techniques. To enhance the performance of statistical methods, new feature extraction techniques using model spectra and residual autocorrelation, together with resampling-based threshold construction methods, are proposed. Subsequently, simulated acceleration data from a multi degree-of-freedom system is generated to test and compare the efficiency of the existing and proposed algorithms. Data from laboratory experiments conducted on a truss and a large-scale bridge slab model are then used to further validate the damage detection methods and demonstrate the superior performance of proposed algorithms.

Statistical Models for Averaging of the Pump–Probe Traces: Example of Denoising in Terahertz Time-Domain Spectroscopy

NASA Astrophysics Data System (ADS)

Skorobogatiy, Maksim; Sadasivan, Jayesh; Guerboukha, Hichem

2018-05-01

In this paper, we first discuss the main types of noise in a typical pump-probe system, and then focus specifically on terahertz time domain spectroscopy (THz-TDS) setups. We then introduce four statistical models for the noisy pulses obtained in such systems, and detail rigorous mathematical algorithms to de-noise such traces, find the proper averages and characterise various types of experimental noise. Finally, we perform a comparative analysis of the performance, advantages and limitations of the algorithms by testing them on the experimental data collected using a particular THz-TDS system available in our laboratories. We conclude that using advanced statistical models for trace averaging results in the fitting errors that are significantly smaller than those obtained when only a simple statistical average is used.

Signal Statistics and Maximum Likelihood Sequence Estimation in Intensity Modulated Fiber Optic Links Containing a Single Optical Pre-amplifier.

PubMed

Alić, Nikola; Papen, George; Saperstein, Robert; Milstein, Laurence; Fainman, Yeshaiahu

2005-06-13

Exact signal statistics for fiber-optic links containing a single optical pre-amplifier are calculated and applied to sequence estimation for electronic dispersion compensation. The performance is evaluated and compared with results based on the approximate chi-square statistics. We show that detection in existing systems based on exact statistics can be improved relative to using a chi-square distribution for realistic filter shapes. In contrast, for high-spectral efficiency systems the difference between the two approaches diminishes, and performance tends to be less dependent on the exact shape of the filter used.

Fault Diagnosis for Rotating Machinery Using Vibration Measurement Deep Statistical Feature Learning.

PubMed

Li, Chuan; Sánchez, René-Vinicio; Zurita, Grover; Cerrada, Mariela; Cabrera, Diego

2016-06-17

Fault diagnosis is important for the maintenance of rotating machinery. The detection of faults and fault patterns is a challenging part of machinery fault diagnosis. To tackle this problem, a model for deep statistical feature learning from vibration measurements of rotating machinery is presented in this paper. Vibration sensor signals collected from rotating mechanical systems are represented in the time, frequency, and time-frequency domains, each of which is then used to produce a statistical feature set. For learning statistical features, real-value Gaussian-Bernoulli restricted Boltzmann machines (GRBMs) are stacked to develop a Gaussian-Bernoulli deep Boltzmann machine (GDBM). The suggested approach is applied as a deep statistical feature learning tool for both gearbox and bearing systems. The fault classification performances in experiments using this approach are 95.17% for the gearbox, and 91.75% for the bearing system. The proposed approach is compared to such standard methods as a support vector machine, GRBM and a combination model. In experiments, the best fault classification rate was detected using the proposed model. The results show that deep learning with statistical feature extraction has an essential improvement potential for diagnosing rotating machinery faults.

Phonetic diversity, statistical learning, and acquisition of phonology.

PubMed

Pierrehumbert, Janet B

2003-01-01

In learning to perceive and produce speech, children master complex language-specific patterns. Daunting language-specific variation is found both in the segmental domain and in the domain of prosody and intonation. This article reviews the challenges posed by results in phonetic typology and sociolinguistics for the theory of language acquisition. It argues that categories are initiated bottom-up from statistical modes in use of the phonetic space, and sketches how exemplar theory can be used to model the updating of categories once they are initiated. It also argues that bottom-up initiation of categories is successful thanks to the perception-production loop operating in the speech community. The behavior of this loop means that the superficial statistical properties of speech available to the infant indirectly reflect the contrastiveness and discriminability of categories in the adult grammar. The article also argues that the developing system is refined using internal feedback from type statistics over the lexicon, once the lexicon is well-developed. The application of type statistics to a system initiated with surface statistics does not cause a fundamental reorganization of the system. Instead, it exploits confluences across levels of representation which characterize human language and make bootstrapping possible.

Fault Diagnosis for Rotating Machinery Using Vibration Measurement Deep Statistical Feature Learning

PubMed Central

Li, Chuan; Sánchez, René-Vinicio; Zurita, Grover; Cerrada, Mariela; Cabrera, Diego

2016-01-01

Fault diagnosis is important for the maintenance of rotating machinery. The detection of faults and fault patterns is a challenging part of machinery fault diagnosis. To tackle this problem, a model for deep statistical feature learning from vibration measurements of rotating machinery is presented in this paper. Vibration sensor signals collected from rotating mechanical systems are represented in the time, frequency, and time-frequency domains, each of which is then used to produce a statistical feature set. For learning statistical features, real-value Gaussian-Bernoulli restricted Boltzmann machines (GRBMs) are stacked to develop a Gaussian-Bernoulli deep Boltzmann machine (GDBM). The suggested approach is applied as a deep statistical feature learning tool for both gearbox and bearing systems. The fault classification performances in experiments using this approach are 95.17% for the gearbox, and 91.75% for the bearing system. The proposed approach is compared to such standard methods as a support vector machine, GRBM and a combination model. In experiments, the best fault classification rate was detected using the proposed model. The results show that deep learning with statistical feature extraction has an essential improvement potential for diagnosing rotating machinery faults. PMID:27322273

Two decades of change in transportation reflections from transportation statistics annual reports 1994-2014.

DOT National Transportation Integrated Search

2015-01-01

The Bureau of Transportation Statistics (BTS) : provides information to support understanding : and decision-making related to the transportation : system, including the size and extent of the : system, how it is used, how well it works, and its : co...

Displaying Geographically-Based Domestic Statistics

NASA Technical Reports Server (NTRS)

Quann, J.; Dalton, J.; Banks, M.; Helfer, D.; Szczur, M.; Winkert, G.; Billingsley, J.; Borgstede, R.; Chen, J.; Chen, L.;

Data Warehousing: How To Make Your Statistics Meaningful.

ERIC Educational Resources Information Center

Flaherty, William

2001-01-01

Examines how one school district found a way to turn data collection from a disparate mountain of statistics into more useful information by using their Instructional Decision Support System. System software is explained as is how the district solved some data management challenges. (GR)

Local statistics of retinal optic flow for self-motion through natural sceneries.

PubMed

Calow, Dirk; Lappe, Markus

2007-12-01

Image analysis in the visual system is well adapted to the statistics of natural scenes. Investigations of natural image statistics have so far mainly focused on static features. The present study is dedicated to the measurement and the analysis of the statistics of optic flow generated on the retina during locomotion through natural environments. Natural locomotion includes bouncing and swaying of the head and eye movement reflexes that stabilize gaze onto interesting objects in the scene while walking. We investigate the dependencies of the local statistics of optic flow on the depth structure of the natural environment and on the ego-motion parameters. To measure these dependencies we estimate the mutual information between correlated data sets. We analyze the results with respect to the variation of the dependencies over the visual field, since the visual motions in the optic flow vary depending on visual field position. We find that retinal flow direction and retinal speed show only minor statistical interdependencies. Retinal speed is statistically tightly connected to the depth structure of the scene. Retinal flow direction is statistically mostly driven by the relation between the direction of gaze and the direction of ego-motion. These dependencies differ at different visual field positions such that certain areas of the visual field provide more information about ego-motion and other areas provide more information about depth. The statistical properties of natural optic flow may be used to tune the performance of artificial vision systems based on human imitating behavior, and may be useful for analyzing properties of natural vision systems.

Quantifying economic fluctuations by adapting methods of statistical physics

NASA Astrophysics Data System (ADS)

Plerou, Vasiliki

2001-09-01

The first focus of this thesis is the investigation of cross-correlations between the price fluctuations of different stocks using the conceptual framework of random matrix theory (RMT), developed in physics to describe the statistical properties of energy-level spectra of complex nuclei. RMT makes predictions for the statistical properties of matrices that are universal, i.e., do not depend on the interactions between the elements comprising the system. In physical systems, deviations from the predictions of RMT provide clues regarding the mechanisms controlling the dynamics of a given system so this framework is of potential value if applied to economic systems. This thesis compares the statistics of cross-correlation matrix C-whose elements Cij are the correlation coefficients of price fluctuations of stock i and j-against the ``null hypothesis'' of a random matrix having the same symmetry properties. It is shown that comparison of the eigenvalue statistics of C with RMT results can be used to distinguish random and non-random parts of C. The non-random part of C which deviates from RMT results, provides information regarding genuine cross-correlations between stocks. The interpretations and potential practical utility of these deviations are also investigated. The second focus is the characterization of the dynamics of stock price fluctuations. The statistical properties of the changes G Δt in price over a time interval Δ t are quantified and the statistical relation between G Δt and the trading activity-measured by the number of transactions NΔ t in the interval Δt is investigated. The statistical properties of the volatility, i.e., the time dependent standard deviation of price fluctuations, is related to two microscopic quantities: NΔt and the variance W2Dt of the price changes for all transactions in the interval Δ t. In addition, the statistical relationship between G Δt and the number of shares QΔt traded in Δ t is investigated.

Statistical physics of the symmetric group.

PubMed

Williams, Mobolaji

2017-04-01

Ordered chains (such as chains of amino acids) are ubiquitous in biological cells, and these chains perform specific functions contingent on the sequence of their components. Using the existence and general properties of such sequences as a theoretical motivation, we study the statistical physics of systems whose state space is defined by the possible permutations of an ordered list, i.e., the symmetric group, and whose energy is a function of how certain permutations deviate from some chosen correct ordering. Such a nonfactorizable state space is quite different from the state spaces typically considered in statistical physics systems and consequently has novel behavior in systems with interacting and even noninteracting Hamiltonians. Various parameter choices of a mean-field model reveal the system to contain five different physical regimes defined by two transition temperatures, a triple point, and a quadruple point. Finally, we conclude by discussing how the general analysis can be extended to state spaces with more complex combinatorial properties and to other standard questions of statistical mechanics models.

Statistical physics of the symmetric group

NASA Astrophysics Data System (ADS)

Williams, Mobolaji

2017-04-01

Ordered chains (such as chains of amino acids) are ubiquitous in biological cells, and these chains perform specific functions contingent on the sequence of their components. Using the existence and general properties of such sequences as a theoretical motivation, we study the statistical physics of systems whose state space is defined by the possible permutations of an ordered list, i.e., the symmetric group, and whose energy is a function of how certain permutations deviate from some chosen correct ordering. Such a nonfactorizable state space is quite different from the state spaces typically considered in statistical physics systems and consequently has novel behavior in systems with interacting and even noninteracting Hamiltonians. Various parameter choices of a mean-field model reveal the system to contain five different physical regimes defined by two transition temperatures, a triple point, and a quadruple point. Finally, we conclude by discussing how the general analysis can be extended to state spaces with more complex combinatorial properties and to other standard questions of statistical mechanics models.

Reconciling statistical and systems science approaches to public health.

PubMed

Ip, Edward H; Rahmandad, Hazhir; Shoham, David A; Hammond, Ross; Huang, Terry T-K; Wang, Youfa; Mabry, Patricia L

2013-10-01

Although systems science has emerged as a set of innovative approaches to study complex phenomena, many topically focused researchers including clinicians and scientists working in public health are somewhat befuddled by this methodology that at times appears to be radically different from analytic methods, such as statistical modeling, to which the researchers are accustomed. There also appears to be conflicts between complex systems approaches and traditional statistical methodologies, both in terms of their underlying strategies and the languages they use. We argue that the conflicts are resolvable, and the sooner the better for the field. In this article, we show how statistical and systems science approaches can be reconciled, and how together they can advance solutions to complex problems. We do this by comparing the methods within a theoretical framework based on the work of population biologist Richard Levins. We present different types of models as representing different tradeoffs among the four desiderata of generality, realism, fit, and precision.

Reconciling Statistical and Systems Science Approaches to Public Health

PubMed Central

Ip, Edward H.; Rahmandad, Hazhir; Shoham, David A.; Hammond, Ross; Huang, Terry T.-K.; Wang, Youfa; Mabry, Patricia L.

2016-01-01

Although systems science has emerged as a set of innovative approaches to study complex phenomena, many topically focused researchers including clinicians and scientists working in public health are somewhat befuddled by this methodology that at times appears to be radically different from analytic methods, such as statistical modeling, to which the researchers are accustomed. There also appears to be conflicts between complex systems approaches and traditional statistical methodologies, both in terms of their underlying strategies and the languages they use. We argue that the conflicts are resolvable, and the sooner the better for the field. In this article, we show how statistical and systems science approaches can be reconciled, and how together they can advance solutions to complex problems. We do this by comparing the methods within a theoretical framework based on the work of population biologist Richard Levins. We present different types of models as representing different tradeoffs among the four desiderata of generality, realism, fit, and precision. PMID:24084395

The 1985 Army Experience Survey. Data Sourcebook and User’s Manual

DTIC Science & Technology

1986-01-01

on the survey data file produced for the 1985 AES.- 4 The survey data are available in Operating System (OS) as well as Statistical Analysis System ...version of the survey data files was produced using the Statistical Analysis System (SASJ. The survey data were also produced in Operating System (OS...impacts upon future enlistments. In order iThe OS data file was designed to make the survey data accessible on any IBM-compatible computer system . 3 N’ to

Applications of the DOE/NASA wind turbine engineering information system

NASA Technical Reports Server (NTRS)

Neustadter, H. E.; Spera, D. A.

1981-01-01

A statistical analysis of data obtained from the Technology and Engineering Information Systems was made. The systems analyzed consist of the following elements: (1) sensors which measure critical parameters (e.g., wind speed and direction, output power, blade loads and component vibrations); (2) remote multiplexing units (RMUs) on each wind turbine which frequency-modulate, multiplex and transmit sensor outputs; (3) on-site instrumentation to record, process and display the sensor output; and (4) statistical analysis of data. Two examples of the capabilities of these systems are presented. The first illustrates the standardized format for application of statistical analysis to each directly measured parameter. The second shows the use of a model to estimate the variability of the rotor thrust loading, which is a derived parameter.

MAI statistics estimation and analysis in a DS-CDMA system

NASA Astrophysics Data System (ADS)

Alami Hassani, A.; Zouak, M.; Mrabti, M.; Abdi, F.

2018-05-01

A primary limitation of Direct Sequence Code Division Multiple Access DS-CDMA link performance and system capacity is multiple access interference (MAI). To examine the performance of CDMA systems in the presence of MAI, i.e., in a multiuser environment, several works assumed that the interference can be approximated by a Gaussian random variable. In this paper, we first develop a new and simple approach to characterize the MAI in a multiuser system. In addition to statistically quantifying the MAI power, the paper also proposes a statistical model for both variance and mean of the MAI for synchronous and asynchronous CDMA transmission. We show that the MAI probability density function (PDF) is Gaussian for the equal-received-energy case and validate it by computer simulations.

Detecting temperature fluctuations at equilibrium.

PubMed

Dixit, Purushottam D

2015-05-21

The Gibbs and the Boltzmann definition of temperature agree only in the macroscopic limit. The ambiguity in identifying the equilibrium temperature of a finite-sized 'small' system exchanging energy with a bath is usually understood as a limitation of conventional statistical mechanics. We interpret this ambiguity as resulting from a stochastically fluctuating temperature coupled with the phase space variables giving rise to a broad temperature distribution. With this ansatz, we develop the equilibrium statistics and dynamics of small systems. Numerical evidence using an analytically tractable model shows that the effects of temperature fluctuations can be detected in the equilibrium and dynamical properties of the phase space of the small system. Our theory generalizes statistical mechanics to small systems relevant in biophysics and nanotechnology.

SHARE: system design and case studies for statistical health information release

PubMed Central

Gardner, James; Xiong, Li; Xiao, Yonghui; Gao, Jingjing; Post, Andrew R; Jiang, Xiaoqian; Ohno-Machado, Lucila

2013-01-01

Objectives We present SHARE, a new system for statistical health information release with differential privacy. We present two case studies that evaluate the software on real medical datasets and demonstrate the feasibility and utility of applying the differential privacy framework on biomedical data. Materials and Methods SHARE releases statistical information in electronic health records with differential privacy, a strong privacy framework for statistical data release. It includes a number of state-of-the-art methods for releasing multidimensional histograms and longitudinal patterns. We performed a variety of experiments on two real datasets, the surveillance, epidemiology and end results (SEER) breast cancer dataset and the Emory electronic medical record (EeMR) dataset, to demonstrate the feasibility and utility of SHARE. Results Experimental results indicate that SHARE can deal with heterogeneous data present in medical data, and that the released statistics are useful. The Kullback–Leibler divergence between the released multidimensional histograms and the original data distribution is below 0.5 and 0.01 for seven-dimensional and three-dimensional data cubes generated from the SEER dataset, respectively. The relative error for longitudinal pattern queries on the EeMR dataset varies between 0 and 0.3. While the results are promising, they also suggest that challenges remain in applying statistical data release using the differential privacy framework for higher dimensional data. Conclusions SHARE is one of the first systems to provide a mechanism for custodians to release differentially private aggregate statistics for a variety of use cases in the medical domain. This proof-of-concept system is intended to be applied to large-scale medical data warehouses. PMID:23059729

A Management Information System Model for Program Management. Ph.D. Thesis - Oklahoma State Univ.; [Computerized Systems Analysis

NASA Technical Reports Server (NTRS)

Shipman, D. L.

1972-01-01

The development of a model to simulate the information system of a program management type of organization is reported. The model statistically determines the following parameters: type of messages, destinations, delivery durations, type processing, processing durations, communication channels, outgoing messages, and priorites. The total management information system of the program management organization is considered, including formal and informal information flows and both facilities and equipment. The model is written in General Purpose System Simulation 2 computer programming language for use on the Univac 1108, Executive 8 computer. The model is simulated on a daily basis and collects queue and resource utilization statistics for each decision point. The statistics are then used by management to evaluate proposed resource allocations, to evaluate proposed changes to the system, and to identify potential problem areas. The model employs both empirical and theoretical distributions which are adjusted to simulate the information flow being studied.

The non-equilibrium statistical mechanics of a simple geophysical fluid dynamics model

NASA Astrophysics Data System (ADS)

Verkley, Wim; Severijns, Camiel

2014-05-01

Lorenz [1] has devised a dynamical system that has proved to be very useful as a benchmark system in geophysical fluid dynamics. The system in its simplest form consists of a periodic array of variables that can be associated with an atmospheric field on a latitude circle. The system is driven by a constant forcing, is damped by linear friction and has a simple advection term that causes the model to behave chaotically if the forcing is large enough. Our aim is to predict the statistics of Lorenz' model on the basis of a given average value of its total energy - obtained from a numerical integration - and the assumption of statistical stationarity. Our method is the principle of maximum entropy [2] which in this case reads: the information entropy of the system's probability density function shall be maximal under the constraints of normalization, a given value of the average total energy and statistical stationarity. Statistical stationarity is incorporated approximately by using `stationarity constraints', i.e., by requiring that the average first and possibly higher-order time-derivatives of the energy are zero in the maximization of entropy. The analysis [3] reveals that, if the first stationarity constraint is used, the resulting probability density function rather accurately reproduces the statistics of the individual variables. If the second stationarity constraint is used as well, the correlations between the variables are also reproduced quite adequately. The method can be generalized straightforwardly and holds the promise of a viable non-equilibrium statistical mechanics of the forced-dissipative systems of geophysical fluid dynamics. [1] E.N. Lorenz, 1996: Predictability - A problem partly solved, in Proc. Seminar on Predictability (ECMWF, Reading, Berkshire, UK), Vol. 1, pp. 1-18. [2] E.T. Jaynes, 2003: Probability Theory - The Logic of Science (Cambridge University Press, Cambridge). [3] W.T.M. Verkley and C.A. Severijns, 2014: The maximum entropy principle applied to a dynamical system proposed by Lorenz, Eur. Phys. J. B, 87:7, http://dx.doi.org/10.1140/epjb/e2013-40681-2 (open access).

A Review of Statistical Disclosure Control Techniques Employed by Web-Based Data Query Systems.

PubMed

Matthews, Gregory J; Harel, Ofer; Aseltine, Robert H

We systematically reviewed the statistical disclosure control techniques employed for releasing aggregate data in Web-based data query systems listed in the National Association for Public Health Statistics and Information Systems (NAPHSIS). Each Web-based data query system was examined to see whether (1) it employed any type of cell suppression, (2) it used secondary cell suppression, and (3) suppressed cell counts could be calculated. No more than 30 minutes was spent on each system. Of the 35 systems reviewed, no suppression was observed in more than half (n = 18); observed counts below the threshold were observed in 2 sites; and suppressed values were recoverable in 9 sites. Six sites effectively suppressed small counts. This inquiry has revealed substantial weaknesses in the protective measures used in data query systems containing sensitive public health data. Many systems utilized no disclosure control whatsoever, and the vast majority of those that did deployed it inconsistently or inadequately.

Rule-based statistical data mining agents for an e-commerce application

NASA Astrophysics Data System (ADS)

Qin, Yi; Zhang, Yan-Qing; King, K. N.; Sunderraman, Rajshekhar

2003-03-01

Intelligent data mining techniques have useful e-Business applications. Because an e-Commerce application is related to multiple domains such as statistical analysis, market competition, price comparison, profit improvement and personal preferences, this paper presents a hybrid knowledge-based e-Commerce system fusing intelligent techniques, statistical data mining, and personal information to enhance QoS (Quality of Service) of e-Commerce. A Web-based e-Commerce application software system, eDVD Web Shopping Center, is successfully implemented uisng Java servlets and an Oracle81 database server. Simulation results have shown that the hybrid intelligent e-Commerce system is able to make smart decisions for different customers.

CISN ShakeAlert Earthquake Early Warning System Monitoring Tools

NASA Astrophysics Data System (ADS)

Henson, I. H.; Allen, R. M.; Neuhauser, D. S.

2015-12-01

CISN ShakeAlert is a prototype earthquake early warning system being developed and tested by the California Integrated Seismic Network. The system has recently been expanded to support redundant data processing and communications. It now runs on six machines at three locations with ten Apache ActiveMQ message brokers linking together 18 waveform processors, 12 event association processes and 4 Decision Module alert processes. The system ingests waveform data from about 500 stations and generates many thousands of triggers per day, from which a small portion produce earthquake alerts. We have developed interactive web browser system-monitoring tools that display near real time state-of-health and performance information. This includes station availability, trigger statistics, communication and alert latencies. Connections to regional earthquake catalogs provide a rapid assessment of the Decision Module hypocenter accuracy. Historical performance can be evaluated, including statistics for hypocenter and origin time accuracy and alert time latencies for different time periods, magnitude ranges and geographic regions. For the ElarmS event associator, individual earthquake processing histories can be examined, including details of the transmission and processing latencies associated with individual P-wave triggers. Individual station trigger and latency statistics are available. Detailed information about the ElarmS trigger association process for both alerted events and rejected events is also available. The Google Web Toolkit and Map API have been used to develop interactive web pages that link tabular and geographic information. Statistical analysis is provided by the R-Statistics System linked to a PostgreSQL database.

Long-ranged Fermi-Pasta-Ulam systems in thermal contact: Crossover from q-statistics to Boltzmann-Gibbs statistics

NASA Astrophysics Data System (ADS)

Bagchi, Debarshee; Tsallis, Constantino

2017-04-01

The relaxation to equilibrium of two long-range-interacting Fermi-Pasta-Ulam-like models (β type) in thermal contact is numerically studied. These systems, with different sizes and energy densities, are coupled to each other by a few thermal contacts which are short-range harmonic springs. By using the kinetic definition of temperature, we compute the time evolution of temperature and energy density of the two systems. Eventually, for some time t >teq, the temperature and energy density of the coupled system equilibrate to values consistent with standard Boltzmann-Gibbs thermostatistics. The equilibration time teq depends on the system size N as teq ∼Nγ where γ ≃ 1.8. We compute the velocity distribution P (v) of the oscillators of the two systems during the relaxation process. We find that P (v) is non-Gaussian and is remarkably close to a q-Gaussian distribution for all times before thermal equilibrium is reached. During the relaxation process we observe q > 1 while close to t =teq the value of q converges to unity and P (v) approaches a Gaussian. Thus the relaxation phenomenon in long-ranged systems connected by a thermal contact can be generically described as a crossover from q-statistics to Boltzmann-Gibbs statistics.

Computer program uses Monte Carlo techniques for statistical system performance analysis

NASA Technical Reports Server (NTRS)

Wohl, D. P.

1967-01-01

Computer program with Monte Carlo sampling techniques determines the effect of a component part of a unit upon the overall system performance. It utilizes the full statistics of the disturbances and misalignments of each component to provide unbiased results through simulated random sampling.

Statistical description and transport in stochastic magnetic fields

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

Vanden Eijnden, E.; Balescu, R.

1996-03-01

The statistical description of particle motion in a stochastic magnetic field is presented. Starting form the stochastic Liouville equation (or, hybrid kinetic equation) associated with the equations of motion of a test particle, the probability distribution function of the system is obtained for various magnetic fields and collisional processes. The influence of these two ingredients on the statistics of the particle dynamics is stressed. In all cases, transport properties of the system are discussed. {copyright} {ital 1996 American Institute of Physics.}

How multiplicity determines entropy and the derivation of the maximum entropy principle for complex systems.

PubMed

Hanel, Rudolf; Thurner, Stefan; Gell-Mann, Murray

2014-05-13

The maximum entropy principle (MEP) is a method for obtaining the most likely distribution functions of observables from statistical systems by maximizing entropy under constraints. The MEP has found hundreds of applications in ergodic and Markovian systems in statistical mechanics, information theory, and statistics. For several decades there has been an ongoing controversy over whether the notion of the maximum entropy principle can be extended in a meaningful way to nonextensive, nonergodic, and complex statistical systems and processes. In this paper we start by reviewing how Boltzmann-Gibbs-Shannon entropy is related to multiplicities of independent random processes. We then show how the relaxation of independence naturally leads to the most general entropies that are compatible with the first three Shannon-Khinchin axioms, the (c,d)-entropies. We demonstrate that the MEP is a perfectly consistent concept for nonergodic and complex statistical systems if their relative entropy can be factored into a generalized multiplicity and a constraint term. The problem of finding such a factorization reduces to finding an appropriate representation of relative entropy in a linear basis. In a particular example we show that path-dependent random processes with memory naturally require specific generalized entropies. The example is to our knowledge the first exact derivation of a generalized entropy from the microscopic properties of a path-dependent random process.

Transportation statistics annual report 1997 : mobility and access

DOT National Transportation Integrated Search

1997-01-01

This document is the fourth Transportation Statistics Annual Report (TSAR) prepared by the Bureau of Transportation Statistics (BTS) for the President and Congress. As in previous years, it reports on the state of U.S. transportation system at two le...

75 FR 37839 - Proposed Collection, Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-30

... DEPARTMENT OF LABOR Bureau of Labor Statistics Proposed Collection, Comment Request ACTION: Notice... requirements on respondents can be properly assessed. The Bureau of Labor Statistics (BLS) is soliciting... Systems, Bureau of Labor Statistics, Room 4080, 2 Massachusetts Avenue, NE., [[Page 37840

75 FR 5346 - Proposed Collection, Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-02

... DEPARTMENT OF LABOR Bureau of Labor Statistics Proposed Collection, Comment Request ACTION: Notice... requirements on respondents can be properly assessed. The Bureau of Labor Statistics (BLS) is soliciting... Clearance Officer, Division of Management Systems, Bureau of Labor Statistics, Room 4080, 2 Massachusetts...

77 FR 36296 - Proposed Collection, Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-18

... DEPARTMENT OF LABOR Bureau of Labor Statistics Proposed Collection, Comment Request ACTION: Notice... requirements on respondents can be properly assessed. The Bureau of Labor Statistics (BLS) is soliciting... Nora Kincaid, BLS Clearance Officer, Division of Management Systems, Bureau of Labor Statistics, Room...

78 FR 41958 - Proposed Collection, Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-12

... DEPARTMENT OF LABOR Bureau of Labor Statistics Proposed Collection, Comment Request ACTION: Notice... requirements on respondents can be properly assessed. The Bureau of Labor Statistics (BLS) is soliciting... Nora Kincaid, BLS Clearance Officer, Division of Management Systems, Bureau of Labor Statistics, Room...

Mutual interference between statistical summary perception and statistical learning.

PubMed

Zhao, Jiaying; Ngo, Nhi; McKendrick, Ryan; Turk-Browne, Nicholas B

2011-09-01

The visual system is an efficient statistician, extracting statistical summaries over sets of objects (statistical summary perception) and statistical regularities among individual objects (statistical learning). Although these two kinds of statistical processing have been studied extensively in isolation, their relationship is not yet understood. We first examined how statistical summary perception influences statistical learning by manipulating the task that participants performed over sets of objects containing statistical regularities (Experiment 1). Participants who performed a summary task showed no statistical learning of the regularities, whereas those who performed control tasks showed robust learning. We then examined how statistical learning influences statistical summary perception by manipulating whether the sets being summarized contained regularities (Experiment 2) and whether such regularities had already been learned (Experiment 3). The accuracy of summary judgments improved when regularities were removed and when learning had occurred in advance. In sum, calculating summary statistics impeded statistical learning, and extracting statistical regularities impeded statistical summary perception. This mutual interference suggests that statistical summary perception and statistical learning are fundamentally related.

Effective temperature in an interacting vertex system: theory and experiment on artificial spin ice.

PubMed

Nisoli, Cristiano; Li, Jie; Ke, Xianglin; Garand, D; Schiffer, Peter; Crespi, Vincent H

2010-07-23

Frustrated arrays of interacting single-domain nanomagnets provide important model systems for statistical mechanics, as they map closely onto well-studied vertex models and are amenable to direct imaging and custom engineering. Although these systems are manifestly athermal, we demonstrate that an effective temperature, controlled by an external magnetic drive, describes their microstates and therefore their full statistical properties.

Data-Base for Communication Planning. The Basic and Statistical Data Required for the Elaboration of a Plan for a National Communication System.

ERIC Educational Resources Information Center

Rahim, Syed A.

Based in part on a list developed by the United Nations Educational, Scientific, and Cultural Organization (UNESCO) for use in Afghanistan, this document presents a comprehensive checklist of items of statistical and descriptive data required for planning a national communication system. It is noted that such a system provides the vital…

Prototyping a Distributed Information Retrieval System That Uses Statistical Ranking.

ERIC Educational Resources Information Center

Harman, Donna; And Others

1991-01-01

Built using a distributed architecture, this prototype distributed information retrieval system uses statistical ranking techniques to provide better service to the end user. Distributed architecture was shown to be a feasible alternative to centralized or CD-ROM information retrieval, and user testing of the ranking methodology showed both…

Effects of atmospheric turbulence on microwave and millimeter wave satellite communications systems. [attenuation statistics and antenna design

NASA Technical Reports Server (NTRS)

Devasirvatham, D. M. J.; Hodge, D. B.

1981-01-01

A model of the microwave and millimeter wave link in the presence of atmospheric turbulence is presented with emphasis on satellite communications systems. The analysis is based on standard methods of statistical theory. The results are directly usable by the design engineer.

Teaching Statistics with Minitab II.

ERIC Educational Resources Information Center

Ryan, T. A., Jr.; And Others

Minitab is a statistical computing system which uses simple language, produces clear output, and keeps track of bookkeeping automatically. Error checking with English diagnostics and inclusion of several default options help to facilitate use of the system by students. Minitab II is an improved and expanded version of the original Minitab which…

An Automated Circulation System for a Small Technical Library.

ERIC Educational Resources Information Center

Culnan, Mary J.

The traditional manually-controlled circulation records of the Burroughs Corporation Library in Goleta, California, presented problems of inaccuracies, time time-consuming searches, and lack of use statistics. An automated system with the capacity to do file maintenance and statistical record-keeping was implemented on a Burroughts B1700 computer.…

ECG Identification System Using Neural Network with Global and Local Features

ERIC Educational Resources Information Center

Tseng, Kuo-Kun; Lee, Dachao; Chen, Charles

2016-01-01

This paper proposes a human identification system via extracted electrocardiogram (ECG) signals. Two hierarchical classification structures based on global shape feature and local statistical feature is used to extract ECG signals. Global shape feature represents the outline information of ECG signals and local statistical feature extracts the…

Realistic finite temperature simulations of magnetic systems using quantum statistics

NASA Astrophysics Data System (ADS)

Bergqvist, Lars; Bergman, Anders

2018-01-01

We have performed realistic atomistic simulations at finite temperatures using Monte Carlo and atomistic spin dynamics simulations incorporating quantum (Bose-Einstein) statistics. The description is much improved at low temperatures compared to classical (Boltzmann) statistics normally used in these kind of simulations, while at higher temperatures the classical statistics are recovered. This corrected low-temperature description is reflected in both magnetization and the magnetic specific heat, the latter allowing for improved modeling of the magnetic contribution to free energies. A central property in the method is the magnon density of states at finite temperatures, and we have compared several different implementations for obtaining it. The method has no restrictions regarding chemical and magnetic order of the considered materials. This is demonstrated by applying the method to elemental ferromagnetic systems, including Fe and Ni, as well as Fe-Co random alloys and the ferrimagnetic system GdFe3.

Make measurable what is not so: national monitoring of the status of persons with intellectual disability.

PubMed

Fujiura, Glenn T; Rutkowski-Kmitta, Violet; Owen, Randall

2010-12-01

Statistics are critical in holding governments accountable for the well-being of citizens with disability. International initiatives are underway to improve the quality of disability statistics, but meaningful ID data is exceptionally rare. The status of ID data was evaluated in a review of 12 national statistical systems. Recurring data collection by national ministries was identified and the availability of measures of poverty, exclusion, and disadvantage was assessed. A total of 131 recurring systems coordinated by 50 different ministries were identified. The majority included general disability but less than 25% of the systems screened ID. Of these, few provided policy-relevant data. The scope of ID data was dismal at best, though a significant statistical infrastructure exists for the integration of ID data. Advocacy will be necessary. There is no optimal form of data monitoring, and decisions regarding priorities in purpose, targeted audiences, and the goals for surveillance must be resolved.

Method and system for efficient video compression with low-complexity encoder

NASA Technical Reports Server (NTRS)

Chen, Jun (Inventor); He, Dake (Inventor); Sheinin, Vadim (Inventor); Jagmohan, Ashish (Inventor); Lu, Ligang (Inventor)

2012-01-01

Disclosed are a method and system for video compression, wherein the video encoder has low computational complexity and high compression efficiency. The disclosed system comprises a video encoder and a video decoder, wherein the method for encoding includes the steps of converting a source frame into a space-frequency representation; estimating conditional statistics of at least one vector of space-frequency coefficients; estimating encoding rates based on the said conditional statistics; and applying Slepian-Wolf codes with the said computed encoding rates. The preferred method for decoding includes the steps of; generating a side-information vector of frequency coefficients based on previously decoded source data, encoder statistics, and previous reconstructions of the source frequency vector; and performing Slepian-Wolf decoding of at least one source frequency vector based on the generated side-information, the Slepian-Wolf code bits and the encoder statistics.

[Evaluation on application of China Disease Prevention and Control Information System of Hydatid Disease Ⅰ Current status at the provincial level].

PubMed

Zhi-Hua, Zhang; Qing, Yu; Tian, Tian; Wei-Ping, Wu; Ning, Xiao

2016-03-31

To evaluate the application status of China Disease Prevention and Control Information System of Hydatid Disease, in which questions existed are summarized in order to promote the system update. A questionnaire was designed and distributed to Inner Mongolia, Sichuan, Tibet, Gansu, Qinghai, Ningxia, Xinjiang and Xinjiang Production and Construction Corps to evaluate the application status of China Disease Prevention and Control Information System of Hydatid Disease assistant with telephone. The recovery rate of questionnaires was 87.5%. The statistics of closed questions showed that national application rate of the China Disease Prevention and Control Information System of Hydatid Disease was 100%, of which 15.3% were low frequency users, 57.1% believed the system was necessary, 28.6% considered it was dispensable, and 14.3% believed that it was totally unnecessary. The statistics of open-ended questions indicated that 6 endemic regions suggested to increase the guidance and training, while 4 endemic regions had opinions on sharing the information of the national infectious disease reporting systems and hydatid disease prevention and control information system, and the opinions on turning monthly report to quarterly report, and increasing statistics and analysis module, and 3 endemic regions deemed that the system had logic errors and defects. The problems of the system are mainly focused on the existence of systemic deficiencies and logic errors, lacking of statistical parameters and corresponding analysis function module, and lacking of the guidance and training, which limits the use of the system. Therefore, these problems should be resolved.

On Ruch's Principle of Decreasing Mixing Distance in classical statistical physics

NASA Astrophysics Data System (ADS)

Busch, Paul; Quadt, Ralf

1990-10-01

Ruch's Principle of Decreasing Mixing Distance is reviewed as a statistical physical principle and its basic suport and geometric interpretation, the Ruch-Schranner-Seligman theorem, is generalized to be applicable to a large representative class of classical statistical systems.

Bootstrap Methods: A Very Leisurely Look.

ERIC Educational Resources Information Center

Hinkle, Dennis E.; Winstead, Wayland H.

The Bootstrap method, a computer-intensive statistical method of estimation, is illustrated using a simple and efficient Statistical Analysis System (SAS) routine. The utility of the method for generating unknown parameters, including standard errors for simple statistics, regression coefficients, discriminant function coefficients, and factor…

ISSUES IN THE STATISTICAL ANALYSIS OF SMALL-AREA HEALTH DATA. (R825173)

EPA Science Inventory

The availability of geographically indexed health and population data, with advances in computing, geographical information systems and statistical methodology, have opened the way for serious exploration of small area health statistics based on routine data. Such analyses may be...

76 FR 6161 - Proposed Collection, Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-03

... DEPARTMENT OF LABOR Bureau of Labor Statistics Proposed Collection, Comment Request ACTION: Notice... requirements on respondents can be properly assessed. The Bureau of Labor Statistics (BLS) is soliciting... comments to Carol Rowan, BLS Clearance Officer, Division of Management Systems, Bureau of Labor Statistics...

77 FR 27798 - Proposed Collection, Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-11

... DEPARTMENT OF LABOR Bureau of Labor Statistics Proposed Collection, Comment Request ACTION: Notice... requirements on respondents can be properly assessed. The Bureau of Labor Statistics (BLS) is soliciting... comments to Carol Rowan, BLS Clearance Officer, Division of Management Systems, Bureau of Labor Statistics...

Output statistics of laser anemometers in sparsely seeded flows

NASA Technical Reports Server (NTRS)

Edwards, R. V.; Jensen, A. S.

1982-01-01

It is noted that until very recently, research on this topic concentrated on the particle arrival statistics and the influence of the optical parameters on them. Little attention has been paid to the influence of subsequent processing on the measurement statistics. There is also controversy over whether the effects of the particle statistics can be measured. It is shown here that some of the confusion derives from a lack of understanding of the experimental parameters that are to be controlled or known. A rigorous framework is presented for examining the measurement statistics of such systems. To provide examples, two problems are then addressed. The first has to do with a sample and hold processor, the second with what is called a saturable processor. The sample and hold processor converts the output to a continuous signal by holding the last reading until a new one is obtained. The saturable system is one where the maximum processable rate is arrived at by the dead time of some unit in the system. At high particle rates, the processed rate is determined through the dead time.

STATISTICAL DATA ON CHEMICAL COMPOUNDS.

DTIC Science & Technology

DATA STORAGE SYSTEMS, FEASIBILITY STUDIES, COMPUTERS, STATISTICAL DATA , DOCUMENTS, ARMY...CHEMICAL COMPOUNDS, INFORMATION RETRIEVAL), (*INFORMATION RETRIEVAL, CHEMICAL COMPOUNDS), MOLECULAR STRUCTURE, BIBLIOGRAPHIES, DATA PROCESSING

Losing Count: The Federal Statistical System. Population Trends and Public Policy Occasional Paper Number 16.

ERIC Educational Resources Information Center

Wallman, Katherine K.

The main responsibility of the U.S. Bureau of the Census, Bureau of Labor Statistics, and the National Centers for Health and Education Statistics is to collect, process, analyze, and disseminate statistical data on the economic, physical, and social characteristics of the United States. Under the Paperwork Reduction Act of 1980, the federal…

Use of statistical study methods for the analysis of the results of the imitation modeling of radiation transfer

NASA Astrophysics Data System (ADS)

Alekseenko, M. A.; Gendrina, I. Yu.

2017-11-01

Recently, due to the abundance of various types of observational data in the systems of vision through the atmosphere and the need for their processing, the use of various methods of statistical research in the study of such systems as correlation-regression analysis, dynamic series, variance analysis, etc. is actual. We have attempted to apply elements of correlation-regression analysis for the study and subsequent prediction of the patterns of radiation transfer in these systems same as in the construction of radiation models of the atmosphere. In this paper, we present some results of statistical processing of the results of numerical simulation of the characteristics of vision systems through the atmosphere obtained with the help of a special software package.1

Data exploration systems for databases

NASA Technical Reports Server (NTRS)

Greene, Richard J.; Hield, Christopher

1992-01-01

Data exploration systems apply machine learning techniques, multivariate statistical methods, information theory, and database theory to databases to identify significant relationships among the data and summarize information. The result of applying data exploration systems should be a better understanding of the structure of the data and a perspective of the data enabling an analyst to form hypotheses for interpreting the data. This paper argues that data exploration systems need a minimum amount of domain knowledge to guide both the statistical strategy and the interpretation of the resulting patterns discovered by these systems.

Computing physical properties with quantum Monte Carlo methods with statistical fluctuations independent of system size.

PubMed

Assaraf, Roland

2014-12-01

We show that the recently proposed correlated sampling without reweighting procedure extends the locality (asymptotic independence of the system size) of a physical property to the statistical fluctuations of its estimator. This makes the approach potentially vastly more efficient for computing space-localized properties in large systems compared with standard correlated methods. A proof is given for a large collection of noninteracting fragments. Calculations on hydrogen chains suggest that this behavior holds not only for systems displaying short-range correlations, but also for systems with long-range correlations.

Load balancing for massively-parallel soft-real-time systems

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

Hailperin, M.

1988-09-01

Global load balancing, if practical, would allow the effective use of massively-parallel ensemble architectures for large soft-real-problems. The challenge is to replace quick global communications, which is impractical in a massively-parallel system, with statistical techniques. In this vein, the author proposes a novel approach to decentralized load balancing based on statistical time-series analysis. Each site estimates the system-wide average load using information about past loads of individual sites and attempts to equal that average. This estimation process is practical because the soft-real-time systems of interest naturally exhibit loads that are periodic, in a statistical sense akin to seasonality in econometrics.more » It is shown how this load-characterization technique can be the foundation for a load-balancing system in an architecture employing cut-through routing and an efficient multicast protocol.« less

A novel conductivity mechanism of highly disordered carbon systems based on an investigation of graph zeta function

NASA Astrophysics Data System (ADS)

Matsutani, Shigeki; Sato, Iwao

2017-09-01

In the previous report (Matsutani and Suzuki, 2000 [21]), by proposing the mechanism under which electric conductivity is caused by the activational hopping conduction with the Wigner surmise of the level statistics, the temperature-dependent of electronic conductivity of a highly disordered carbon system was evaluated including apparent metal-insulator transition. Since the system consists of small pieces of graphite, it was assumed that the reason why the level statistics appears is due to the behavior of the quantum chaos in each granular graphite. In this article, we revise the assumption and show another origin of the Wigner surmise, which is more natural for the carbon system based on a recent investigation of graph zeta function in graph theory. Our method can be applied to the statistical treatment of the electronic properties of the randomized molecular system in general.

A fully redundant double difference algorithm for obtaining minimum variance estimates from GPS observations

NASA Technical Reports Server (NTRS)

Melbourne, William G.

1986-01-01

In double differencing a regression system obtained from concurrent Global Positioning System (GPS) observation sequences, one either undersamples the system to avoid introducing colored measurement statistics, or one fully samples the system incurring the resulting non-diagonal covariance matrix for the differenced measurement errors. A suboptimal estimation result will be obtained in the undersampling case and will also be obtained in the fully sampled case unless the color noise statistics are taken into account. The latter approach requires a least squares weighting matrix derived from inversion of a non-diagonal covariance matrix for the differenced measurement errors instead of inversion of the customary diagonal one associated with white noise processes. Presented is the so-called fully redundant double differencing algorithm for generating a weighted double differenced regression system that yields equivalent estimation results, but features for certain cases a diagonal weighting matrix even though the differenced measurement error statistics are highly colored.

Method for simulating atmospheric turbulence phase effects for multiple time slices and anisoplanatic conditions.

PubMed

Roggemann, M C; Welsh, B M; Montera, D; Rhoadarmer, T A

1995-07-10

Simulating the effects of atmospheric turbulence on optical imaging systems is an important aspect of understanding the performance of these systems. Simulations are particularly important for understanding the statistics of some adaptive-optics system performance measures, such as the mean and variance of the compensated optical transfer function, and for understanding the statistics of estimators used to reconstruct intensity distributions from turbulence-corrupted image measurements. Current methods of simulating the performance of these systems typically make use of random phase screens placed in the system pupil. Methods exist for making random draws of phase screens that have the correct spatial statistics. However, simulating temporal effects and anisoplanatism requires one or more phase screens at different distances from the aperture, possibly moving with different velocities. We describe and demonstrate a method for creating random draws of phase screens with the correct space-time statistics for a bitrary turbulence and wind-velocity profiles, which can be placed in the telescope pupil in simulations. Results are provided for both the von Kármán and the Kolmogorov turbulence spectra. We also show how to simulate anisoplanatic effects with this technique.

Statistical Teleodynamics: Toward a Theory of Emergence.

PubMed

Venkatasubramanian, Venkat

2017-10-24

The central scientific challenge of the 21st century is developing a mathematical theory of emergence that can explain and predict phenomena such as consciousness and self-awareness. The most successful research program of the 20th century, reductionism, which goes from the whole to parts, seems unable to address this challenge. This is because addressing this challenge inherently requires an opposite approach, going from parts to the whole. In addition, reductionism, by the very nature of its inquiry, typically does not concern itself with teleology or purposeful behavior. Modeling emergence, in contrast, requires the addressing of teleology. Together, these two requirements present a formidable challenge in developing a successful mathematical theory of emergence. In this article, I describe a new theory of emergence, called statistical teleodynamics, that addresses certain aspects of the general problem. Statistical teleodynamics is a mathematical framework that unifies three seemingly disparate domains-purpose-free entities in statistical mechanics, human engineered teleological systems in systems engineering, and nature-evolved teleological systems in biology and sociology-within the same conceptual formalism. This theory rests on several key conceptual insights, the most important one being the recognition that entropy mathematically models the concept of fairness in economics and philosophy and, equivalently, the concept of robustness in systems engineering. These insights help prove that the fairest inequality of income is a log-normal distribution, which will emerge naturally at equilibrium in an ideal free market society. Similarly, the theory predicts the emergence of the three classes of network organization-exponential, scale-free, and Poisson-seen widely in a variety of domains. Statistical teleodynamics is the natural generalization of statistical thermodynamics, the most successful parts-to-whole systems theory to date, but this generalization is only a modest step toward a more comprehensive mathematical theory of emergence.

International Community Development Statistical Bulletin. Spring 1968 General Edition.

ERIC Educational Resources Information Center

Community Development Foundation, New York, NY.

The Spring 1968 general edition of the International Community Development Statistical Bulletin describes its reporting system based on the International Standard Classification of Community Development Activities and a special project registration and progress form; briefly summarizes overall international data; and presents statistics on…

Application of Statistics in Engineering Technology Programs

ERIC Educational Resources Information Center

Zhan, Wei; Fink, Rainer; Fang, Alex

2010-01-01

Statistics is a critical tool for robustness analysis, measurement system error analysis, test data analysis, probabilistic risk assessment, and many other fields in the engineering world. Traditionally, however, statistics is not extensively used in undergraduate engineering technology (ET) programs, resulting in a major disconnect from industry…

Mathematical and Statistical Software Index. Final Report.

ERIC Educational Resources Information Center

Black, Doris E., Comp.

Brief descriptions are provided of general-purpose mathematical and statistical software, including 27 "stand-alone" programs, three subroutine systems, and two nationally recognized statistical packages, which are available in the Air Force Human Resources Laboratory (AFHRL) software library. This index was created to enable researchers…

14 CFR 234.6 - Baggage-handling statistics.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Baggage-handling statistics. 234.6 Section 234.6 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION... statistics. Each reporting carrier shall report monthly to the Department on a domestic system basis...

14 CFR 234.6 - Baggage-handling statistics.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Baggage-handling statistics. 234.6 Section 234.6 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION... statistics. Each reporting carrier shall report monthly to the Department on a domestic system basis...

Statistical properties of Chinese phonemic networks

NASA Astrophysics Data System (ADS)

Yu, Shuiyuan; Liu, Haitao; Xu, Chunshan

2011-04-01

The study of properties of speech sound systems is of great significance in understanding the human cognitive mechanism and the working principles of speech sound systems. Some properties of speech sound systems, such as the listener-oriented feature and the talker-oriented feature, have been unveiled with the statistical study of phonemes in human languages and the research of the interrelations between human articulatory gestures and the corresponding acoustic parameters. With all the phonemes of speech sound systems treated as a coherent whole, our research, which focuses on the dynamic properties of speech sound systems in operation, investigates some statistical parameters of Chinese phoneme networks based on real text and dictionaries. The findings are as follows: phonemic networks have high connectivity degrees and short average distances; the degrees obey normal distribution and the weighted degrees obey power law distribution; vowels enjoy higher priority than consonants in the actual operation of speech sound systems; the phonemic networks have high robustness against targeted attacks and random errors. In addition, for investigating the structural properties of a speech sound system, a statistical study of dictionaries is conducted, which shows the higher frequency of shorter words and syllables and the tendency that the longer a word is, the shorter the syllables composing it are. From these structural properties and dynamic properties one can derive the following conclusion: the static structure of a speech sound system tends to promote communication efficiency and save articulation effort while the dynamic operation of this system gives preference to reliable transmission and easy recognition. In short, a speech sound system is an effective, efficient and reliable communication system optimized in many aspects.

A Systems Analysis of the Library and Information Science Statistical Data System: The Preliminary Study. Interim Report.

ERIC Educational Resources Information Center

Hamburg, Morris; And Others

The long-term goal of this investigation is to design and establish a national model for a system of library statistical data. This is a report on The Preliminary Study which was carried out over an 11-month period ending May, 1969. The objective of The Preliminary Study was to design and delimit The Research Investigation in the most efficient…

Statistical Analysis of Adaptive Beam-Forming Methods

DTIC Science & Technology

1988-05-01

minimum amount of computing resources? * What are the tradeoffs being made when a system design selects block averaging over exponential averaging? Will...understood by many signal processing practitioners, however, is how system parameters and the number of sensors effect the distribution of the... system performance improve and if so by how much? b " It is well known that the noise sampled at adjacent sensors is not statistically independent

Occupational Injury and Illness Surveillance: Conceptual Filters Explain Underreporting

PubMed Central

Azaroff, Lenore S.; Levenstein, Charles; Wegman, David H.

2002-01-01

Occupational health surveillance data are key to effective intervention. However, the US Bureau of Labor Statistics survey significantly underestimates the incidence of work-related injuries and illnesses. Researchers supplement these statistics with data from other systems not designed for surveillance. The authors apply the filter model of Webb et al. to underreporting by the Bureau of Labor Statistics, workers’ compensation wage-replacement documents, physician reporting systems, and medical records of treatment charged to workers’ compensation. Mechanisms are described for the loss of cases at successive steps of documentation. Empirical findings indicate that workers repeatedly risk adverse consequences for attempting to complete these steps, while systems for ensuring their completion are weak or absent. PMID:12197968

Developing points-based risk-scoring systems in the presence of competing risks.

PubMed

Austin, Peter C; Lee, Douglas S; D'Agostino, Ralph B; Fine, Jason P

2016-09-30

Predicting the occurrence of an adverse event over time is an important issue in clinical medicine. Clinical prediction models and associated points-based risk-scoring systems are popular statistical methods for summarizing the relationship between a multivariable set of patient risk factors and the risk of the occurrence of an adverse event. Points-based risk-scoring systems are popular amongst physicians as they permit a rapid assessment of patient risk without the use of computers or other electronic devices. The use of such points-based risk-scoring systems facilitates evidence-based clinical decision making. There is a growing interest in cause-specific mortality and in non-fatal outcomes. However, when considering these types of outcomes, one must account for competing risks whose occurrence precludes the occurrence of the event of interest. We describe how points-based risk-scoring systems can be developed in the presence of competing events. We illustrate the application of these methods by developing risk-scoring systems for predicting cardiovascular mortality in patients hospitalized with acute myocardial infarction. Code in the R statistical programming language is provided for the implementation of the described methods. © 2016 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd. © 2016 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd.

Probabilistic models in human sensorimotor control

PubMed Central

Wolpert, Daniel M.

2009-01-01

Sensory and motor uncertainty form a fundamental constraint on human sensorimotor control. Bayesian decision theory (BDT) has emerged as a unifying framework to understand how the central nervous system performs optimal estimation and control in the face of such uncertainty. BDT has two components: Bayesian statistics and decision theory. Here we review Bayesian statistics and show how it applies to estimating the state of the world and our own body. Recent results suggest that when learning novel tasks we are able to learn the statistical properties of both the world and our own sensory apparatus so as to perform estimation using Bayesian statistics. We review studies which suggest that humans can combine multiple sources of information to form maximum likelihood estimates, can incorporate prior beliefs about possible states of the world so as to generate maximum a posteriori estimates and can use Kalman filter-based processes to estimate time-varying states. Finally, we review Bayesian decision theory in motor control and how the central nervous system processes errors to determine loss functions and optimal actions. We review results that suggest we plan movements based on statistics of our actions that result from signal-dependent noise on our motor outputs. Taken together these studies provide a statistical framework for how the motor system performs in the presence of uncertainty. PMID:17628731

Improvements to an earth observing statistical performance model with applications to LWIR spectral variability

NASA Astrophysics Data System (ADS)

Zhao, Runchen; Ientilucci, Emmett J.

2017-05-01

Hyperspectral remote sensing systems provide spectral data composed of hundreds of narrow spectral bands. Spectral remote sensing systems can be used to identify targets, for example, without physical interaction. Often it is of interested to characterize the spectral variability of targets or objects. The purpose of this paper is to identify and characterize the LWIR spectral variability of targets based on an improved earth observing statistical performance model, known as the Forecasting and Analysis of Spectroradiometric System Performance (FASSP) model. FASSP contains three basic modules including a scene model, sensor model and a processing model. Instead of using mean surface reflectance only as input to the model, FASSP transfers user defined statistical characteristics of a scene through the image chain (i.e., from source to sensor). The radiative transfer model, MODTRAN, is used to simulate the radiative transfer based on user defined atmospheric parameters. To retrieve class emissivity and temperature statistics, or temperature / emissivity separation (TES), a LWIR atmospheric compensation method is necessary. The FASSP model has a method to transform statistics in the visible (ie., ELM) but currently does not have LWIR TES algorithm in place. This paper addresses the implementation of such a TES algorithm and its associated transformation of statistics.

Conditional Probabilities and Collapse in Quantum Measurements

NASA Astrophysics Data System (ADS)

Laura, Roberto; Vanni, Leonardo

2008-09-01

We show that including both the system and the apparatus in the quantum description of the measurement process, and using the concept of conditional probabilities, it is possible to deduce the statistical operator of the system after a measurement with a given result, which gives the probability distribution for all possible consecutive measurements on the system. This statistical operator, representing the state of the system after the first measurement, is in general not the same that would be obtained using the postulate of collapse.

Entropy in statistical energy analysis.

PubMed

Le Bot, Alain

2009-03-01

In this paper, the second principle of thermodynamics is discussed in the framework of statistical energy analysis (SEA). It is shown that the "vibrational entropy" and the "vibrational temperature" of sub-systems only depend on the vibrational energy and the number of resonant modes. A SEA system can be described as a thermodynamic system slightly out of equilibrium. In steady-state condition, the entropy exchanged with exterior by sources and dissipation exactly balances the production of entropy by irreversible processes at interface between SEA sub-systems.

Public health information and statistics dissemination efforts for Indonesia on the Internet.

PubMed

Hanani, Febiana; Kobayashi, Takashi; Jo, Eitetsu; Nakajima, Sawako; Oyama, Hiroshi

2011-01-01

To elucidate current issues related to health statistics dissemination efforts on the Internet in Indonesia and to propose a new dissemination website as a solution. A cross-sectional survey was conducted. Sources of statistics were identified using link relationship and Google™ search. Menu used to locate statistics, mode of presentation and means of access to statistics, and available statistics were assessed for each site. Assessment results were used to derive design specification; a prototype system was developed and evaluated with usability test. 49 sources were identified on 18 governmental, 8 international and 5 non-government websites. Of 49 menus identified, 33% used non-intuitive titles and lead to inefficient search. 69% of them were on government websites. Of 31 websites, only 39% and 23% used graph/chart and map for presentation. Further, only 32%, 39% and 19% provided query, export and print feature. While >50% sources reported morbidity, risk factor and service provision statistics, <40% sources reported health resource and mortality statistics. Statistics portal website was developed using Joomla!™ content management system. Usability test demonstrated its potential to improve data accessibility. In this study, government's efforts to disseminate statistics in Indonesia are supported by non-governmental and international organizations and existing their information may not be very useful because it is: a) not widely distributed, b) difficult to locate, and c) not effectively communicated. Actions are needed to ensure information usability, and one of such actions is the development of statistics portal website.

The Statistical Interpretation of Entropy: An Activity

ERIC Educational Resources Information Center

Timmberlake, Todd

2010-01-01

The second law of thermodynamics, which states that the entropy of an isolated macroscopic system can increase but will not decrease, is a cornerstone of modern physics. Ludwig Boltzmann argued that the second law arises from the motion of the atoms that compose the system. Boltzmann's statistical mechanics provides deep insight into the…

Statistical basis and outputs of stable isotope mixing models: Comment on Fry (2013)

EPA Science Inventory

A recent article by Fry (2013; Mar Ecol Prog Ser 472:1−13) reviewed approaches to solving underdetermined stable isotope mixing systems, and presented a new graphical approach and set of summary statistics for the analysis of such systems. In his review, Fry (2013) mis-characteri...

Peculiar spectral statistics of ensembles of trees and star-like graphs

NASA Astrophysics Data System (ADS)

Kovaleva, V.; Maximov, Yu; Nechaev, S.; Valba, O.

2017-07-01

In this paper we investigate the eigenvalue statistics of exponentially weighted ensembles of full binary trees and p-branching star graphs. We show that spectral densities of corresponding adjacency matrices demonstrate peculiar ultrametric structure inherent to sparse systems. In particular, the tails of the distribution for binary trees share the ‘Lifshitz singularity’ emerging in the one-dimensional localization, while the spectral statistics of p-branching star-like graphs is less universal, being strongly dependent on p. The hierarchical structure of spectra of adjacency matrices is interpreted as sets of resonance frequencies, that emerge in ensembles of fully branched tree-like systems, known as dendrimers. However, the relaxational spectrum is not determined by the cluster topology, but has rather the number-theoretic origin, reflecting the peculiarities of the rare-event statistics typical for one-dimensional systems with a quenched structural disorder. The similarity of spectral densities of an individual dendrimer and of an ensemble of linear chains with exponential distribution in lengths, demonstrates that dendrimers could be served as simple disorder-less toy models of one-dimensional systems with quenched disorder.

Peculiar spectral statistics of ensembles of trees and star-like graphs

DOE PAGES

Kovaleva, V.; Maximov, Yu; Nechaev, S.; ...

2017-07-11

In this paper we investigate the eigenvalue statistics of exponentially weighted ensembles of full binary trees and p-branching star graphs. We show that spectral densities of corresponding adjacency matrices demonstrate peculiar ultrametric structure inherent to sparse systems. In particular, the tails of the distribution for binary trees share the \\Lifshitz singularity" emerging in the onedimensional localization, while the spectral statistics of p-branching star-like graphs is less universal, being strongly dependent on p. The hierarchical structure of spectra of adjacency matrices is interpreted as sets of resonance frequencies, that emerge in ensembles of fully branched tree-like systems, known as dendrimers. However,more » the relaxational spectrum is not determined by the cluster topology, but has rather the number-theoretic origin, re ecting the peculiarities of the rare-event statistics typical for one-dimensional systems with a quenched structural disorder. The similarity of spectral densities of an individual dendrimer and of ensemble of linear chains with exponential distribution in lengths, demonstrates that dendrimers could be served as simple disorder-less toy models of one-dimensional systems with quenched disorder.« less

Peculiar spectral statistics of ensembles of trees and star-like graphs

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

Kovaleva, V.; Maximov, Yu; Nechaev, S.

In this paper we investigate the eigenvalue statistics of exponentially weighted ensembles of full binary trees and p-branching star graphs. We show that spectral densities of corresponding adjacency matrices demonstrate peculiar ultrametric structure inherent to sparse systems. In particular, the tails of the distribution for binary trees share the \\Lifshitz singularity" emerging in the onedimensional localization, while the spectral statistics of p-branching star-like graphs is less universal, being strongly dependent on p. The hierarchical structure of spectra of adjacency matrices is interpreted as sets of resonance frequencies, that emerge in ensembles of fully branched tree-like systems, known as dendrimers. However,more » the relaxational spectrum is not determined by the cluster topology, but has rather the number-theoretic origin, re ecting the peculiarities of the rare-event statistics typical for one-dimensional systems with a quenched structural disorder. The similarity of spectral densities of an individual dendrimer and of ensemble of linear chains with exponential distribution in lengths, demonstrates that dendrimers could be served as simple disorder-less toy models of one-dimensional systems with quenched disorder.« less

High order statistical signatures from source-driven measurements of subcritical fissile systems

NASA Astrophysics Data System (ADS)

Mattingly, John Kelly

1998-11-01

This research focuses on the development and application of high order statistical analyses applied to measurements performed with subcritical fissile systems driven by an introduced neutron source. The signatures presented are derived from counting statistics of the introduced source and radiation detectors that observe the response of the fissile system. It is demonstrated that successively higher order counting statistics possess progressively higher sensitivity to reactivity. Consequently, these signatures are more sensitive to changes in the composition, fissile mass, and configuration of the fissile assembly. Furthermore, it is shown that these techniques are capable of distinguishing the response of the fissile system to the introduced source from its response to any internal or inherent sources. This ability combined with the enhanced sensitivity of higher order signatures indicates that these techniques will be of significant utility in a variety of applications. Potential applications include enhanced radiation signature identification of weapons components for nuclear disarmament and safeguards applications and augmented nondestructive analysis of spent nuclear fuel. In general, these techniques expand present capabilities in the analysis of subcritical measurements.

A Study on Grid-Square Statistics Based Estimation of Regional Electricity Demand and Regional Potential Capacity of Distributed Generators

NASA Astrophysics Data System (ADS)

Kato, Takeyoshi; Sugimoto, Hiroyuki; Suzuoki, Yasuo

We established a procedure for estimating regional electricity demand and regional potential capacity of distributed generators (DGs) by using a grid square statistics data set. A photovoltaic power system (PV system) for residential use and a co-generation system (CGS) for both residential and commercial use were taken into account. As an example, the result regarding Aichi prefecture was presented in this paper. The statistical data of the number of households by family-type and the number of employees by business category for about 4000 grid-square with 1km × 1km area was used to estimate the floor space or the electricity demand distribution. The rooftop area available for installing PV systems was also estimated with the grid-square statistics data set. Considering the relation between a capacity of existing CGS and a scale-index of building where CGS is installed, the potential capacity of CGS was estimated for three business categories, i.e. hotel, hospital, store. In some regions, the potential capacity of PV systems was estimated to be about 10,000kW/km2, which corresponds to the density of the existing area with intensive installation of PV systems. Finally, we discussed the ratio of regional potential capacity of DGs to regional maximum electricity demand for deducing the appropriate capacity of DGs in the model of future electricity distribution system.

An Analysis of Operational Suitability for Test and Evaluation of Highly Reliable Systems

DTIC Science & Technology

1994-03-04

Exposition," Journal of the American Statistical A iation-59: 353-375 (June 1964). 17. SYS 229, Test and Evaluation Management Coursebook , School of Systems...in hours, 0 is 2-5 the desired MTBCF in hours, R is the number of critical failures, and a is the P[type-I error] of the X2 statistic with 2*R+2...design of experiments (DOE) tables and the use of Bayesian statistics to increase the confidence level of the test results that will be obtained from

5 CFR 297.401 - Conditions of disclosure.

Code of Federal Regulations, 2010 CFR

2010-01-01

... with advance adequate written assurance that the record will be used solely as a statistical research... records; and (ii) Certification that the records will be used only for statistical purposes. (2) These... information from records released for statistical purposes, the system manager will reasonably ensure that the...

18 CFR 3b.225 - Written consent for disclosure.

Code of Federal Regulations, 2010 CFR

2010-04-01

... as a statistical research or reporting record, and the record is to be transferred in a form that is... for statistical purposes. In addition to stripping personally identifying information from records released for statistical purposes, the system manager will ensure that the identity of the individual...

75 FR 41579 - Submitting Airline Data via the Internet

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-16

... Airline Information, RTS-42, Bureau of Transportation Statistics, Research and Innovative Technology... Statistics (BTS), must be submitted electronically (e- filing). The new e-filing system is designed to be... November 30, 2010. P-10 Employment Statistics by Labor Category--due February 20, 2011. A Certification...

Recurrence and interoccurrence behavior of self-organized complex phenomena

NASA Astrophysics Data System (ADS)

Abaimov, S. G.; Turcotte, D. L.; Shcherbakov, R.; Rundle, J. B.

2007-08-01

The sandpile, forest-fire and slider-block models are said to exhibit self-organized criticality. Associated natural phenomena include landslides, wildfires, and earthquakes. In all cases the frequency-size distributions are well approximated by power laws (fractals). Another important aspect of both the models and natural phenomena is the statistics of interval times. These statistics are particularly important for earthquakes. For earthquakes it is important to make a distinction between interoccurrence and recurrence times. Interoccurrence times are the interval times between earthquakes on all faults in a region whereas recurrence times are interval times between earthquakes on a single fault or fault segment. In many, but not all cases, interoccurrence time statistics are exponential (Poissonian) and the events occur randomly. However, the distribution of recurrence times are often Weibull to a good approximation. In this paper we study the interval statistics of slip events using a slider-block model. The behavior of this model is sensitive to the stiffness α of the system, α=kC/kL where kC is the spring constant of the connector springs and kL is the spring constant of the loader plate springs. For a soft system (small α) there are no system-wide events and interoccurrence time statistics of the larger events are Poissonian. For a stiff system (large α), system-wide events dominate the energy dissipation and the statistics of the recurrence times between these system-wide events satisfy the Weibull distribution to a good approximation. We argue that this applicability of the Weibull distribution is due to the power-law (scale invariant) behavior of the hazard function, i.e. the probability that the next event will occur at a time t0 after the last event has a power-law dependence on t0. The Weibull distribution is the only distribution that has a scale invariant hazard function. We further show that the onset of system-wide events is a well defined critical point. We find that the number of system-wide events NSWE satisfies the scaling relation NSWE ∝(α-αC)δ where αC is the critical value of the stiffness. The system-wide events represent a new phase for the slider-block system.

Structural damage detection based on stochastic subspace identification and statistical pattern recognition: I. Theory

NASA Astrophysics Data System (ADS)

Ren, W. X.; Lin, Y. Q.; Fang, S. E.

2011-11-01

One of the key issues in vibration-based structural health monitoring is to extract the damage-sensitive but environment-insensitive features from sampled dynamic response measurements and to carry out the statistical analysis of these features for structural damage detection. A new damage feature is proposed in this paper by using the system matrices of the forward innovation model based on the covariance-driven stochastic subspace identification of a vibrating system. To overcome the variations of the system matrices, a non-singularity transposition matrix is introduced so that the system matrices are normalized to their standard forms. For reducing the effects of modeling errors, noise and environmental variations on measured structural responses, a statistical pattern recognition paradigm is incorporated into the proposed method. The Mahalanobis and Euclidean distance decision functions of the damage feature vector are adopted by defining a statistics-based damage index. The proposed structural damage detection method is verified against one numerical signal and two numerical beams. It is demonstrated that the proposed statistics-based damage index is sensitive to damage and shows some robustness to the noise and false estimation of the system ranks. The method is capable of locating damage of the beam structures under different types of excitations. The robustness of the proposed damage detection method to the variations in environmental temperature is further validated in a companion paper by a reinforced concrete beam tested in the laboratory and a full-scale arch bridge tested in the field.

Pauli structures arising from confined particles interacting via a statistical potential

NASA Astrophysics Data System (ADS)

Batle, Josep; Ciftja, Orion; Farouk, Ahmed; Alkhambashi, Majid; Abdalla, Soliman

2017-09-01

There have been suggestions that the Pauli exclusion principle alone can lead a non-interacting (free) system of identical fermions to form crystalline structures dubbed Pauli crystals. Single-shot imaging experiments for the case of ultra-cold systems of free spin-polarized fermionic atoms in a two-dimensional harmonic trap appear to show geometric arrangements that cannot be characterized as Wigner crystals. This work explores this idea and considers a well-known approach that enables one to treat a quantum system of free fermions as a system of classical particles interacting with a statistical interaction potential. The model under consideration, though classical in nature, incorporates the quantum statistics by endowing the classical particles with an effective interaction potential. The reasonable expectation is that possible Pauli crystal features seen in experiments may manifest in this model that captures the correct quantum statistics as a first order correction. We use the Monte Carlo simulated annealing method to obtain the most stable configurations of finite two-dimensional systems of confined particles that interact with an appropriate statistical repulsion potential. We consider both an isotropic harmonic and a hard-wall confinement potential. Despite minor differences, the most stable configurations observed in our model correspond to the reported Pauli crystals in single-shot imaging experiments of free spin-polarized fermions in a harmonic trap. The crystalline configurations observed appear to be different from the expected classical Wigner crystal structures that would emerge should the confined classical particles had interacted with a pair-wise Coulomb repulsion.

Statistical correlation of structural mode shapes from test measurements and NASTRAN analytical values

NASA Technical Reports Server (NTRS)

Purves, L.; Strang, R. F.; Dube, M. P.; Alea, P.; Ferragut, N.; Hershfeld, D.

1983-01-01

The software and procedures of a system of programs used to generate a report of the statistical correlation between NASTRAN modal analysis results and physical tests results from modal surveys are described. Topics discussed include: a mathematical description of statistical correlation, a user's guide for generating a statistical correlation report, a programmer's guide describing the organization and functions of individual programs leading to a statistical correlation report, and a set of examples including complete listings of programs, and input and output data.

Monitoring the Earth System Grid Federation through the ESGF Dashboard

NASA Astrophysics Data System (ADS)

Fiore, S.; Bell, G. M.; Drach, B.; Williams, D.; Aloisio, G.

2012-12-01

The Climate Model Intercomparison Project, phase 5 (CMIP5) is a global effort coordinated by the World Climate Research Programme (WCRP) involving tens of modeling groups spanning 19 countries. It is expected the CMIP5 distributed data archive will total upwards of 3.5 petabytes, stored across several ESGF Nodes on four continents (North America, Europe, Asia, and Australia). The Earth System Grid Federation (ESGF) provides the IT infrastructure to support the CMIP5. In this regard, the monitoring of the distributed ESGF infrastructure represents a crucial part carried out by the ESGF Dashboard. The ESGF Dashboard is a software component of the ESGF stack, responsible for collecting key information about the status of the federation in terms of: 1) Network topology (peer-groups composition), 2) Node type (host/services mapping), 3) Registered users (including their Identity Providers), 4) System metrics (e.g., round-trip time, service availability, CPU, memory, disk, processes, etc.), 5) Download metrics (both at the Node and federation level). The last class of information is very important since it provides a strong insight of the CMIP5 experiment: the data usage statistics. In this regard, CMCC and LLNL have developed a data analytics management system for the analysis of both node-level and federation-level data usage statistics. It provides data usage statistics aggregated by project, model, experiment, variable, realm, peer node, time, ensemble, datasetname (including version), etc. The back-end of the system is able to infer the data usage information of the entire federation, by carrying out: - at node level: a 18-step reconciliation process on the peer node databases (i.e. node manager and publisher DB) which provides a 15-dimension datawarehouse with local statistics and - at global level: an aggregation process which federates the data usage statistics into a 16-dimension datawarehouse with federation-level data usage statistics. The front-end of the Dashboard system exploits a web desktop approach, which joins the pervasivity of a web application with the flexibility of a desktop one.

The prior statistics of object colors.

PubMed

Koenderink, Jan J

2010-02-01

The prior statistics of object colors is of much interest because extensive statistical investigations of reflectance spectra reveal highly non-uniform structure in color space common to several very different databases. This common structure is due to the visual system rather than to the statistics of environmental structure. Analysis involves an investigation of the proper sample space of spectral reflectance factors and of the statistical consequences of the projection of spectral reflectances on the color solid. Even in the case of reflectance statistics that are translationally invariant with respect to the wavelength dimension, the statistics of object colors is highly non-uniform. The qualitative nature of this non-uniformity is due to trichromacy.

Quantum thermalization through entanglement in an isolated many-body system.

PubMed

Kaufman, Adam M; Tai, M Eric; Lukin, Alexander; Rispoli, Matthew; Schittko, Robert; Preiss, Philipp M; Greiner, Markus

2016-08-19

Statistical mechanics relies on the maximization of entropy in a system at thermal equilibrium. However, an isolated quantum many-body system initialized in a pure state remains pure during Schrödinger evolution, and in this sense it has static, zero entropy. We experimentally studied the emergence of statistical mechanics in a quantum state and observed the fundamental role of quantum entanglement in facilitating this emergence. Microscopy of an evolving quantum system indicates that the full quantum state remains pure, whereas thermalization occurs on a local scale. We directly measured entanglement entropy, which assumes the role of the thermal entropy in thermalization. The entanglement creates local entropy that validates the use of statistical physics for local observables. Our measurements are consistent with the eigenstate thermalization hypothesis. Copyright © 2016, American Association for the Advancement of Science.

[Research & development on computer expert system for forensic bones estimation].

PubMed

Zhao, Jun-ji; Zhang, Jan-zheng; Liu, Nin-guo

2005-08-01

To build an expert system for forensic bones estimation. By using the object oriented method, employing statistical data of forensic anthropology, combining the statistical data frame knowledge representation with productions and also using the fuzzy matching and DS evidence theory method. Software for forensic estimation of sex, age and height with opened knowledge base was designed. This system is reliable and effective, and it would be a good assistant of the forensic technician.

Digest of Educational Statistics, 1962. Bulletin, 1963, No. 10. OE-10024

ERIC Educational Resources Information Center

Office of Education, US Department of Health, Education, and Welfare, 1962

1962-01-01

This digest is a compilation of the more significant statistical material available in the Office of Education on the American educational system. It contains information on a variety of subjects within the broad field of educational statistics, including schools, enrollments, teachers, graduates, educational attainment, finances, and Federal…

Scalable Integrated Region-Based Image Retrieval Using IRM and Statistical Clustering.

ERIC Educational Resources Information Center

Wang, James Z.; Du, Yanping

Statistical clustering is critical in designing scalable image retrieval systems. This paper presents a scalable algorithm for indexing and retrieving images based on region segmentation. The method uses statistical clustering on region features and IRM (Integrated Region Matching), a measure developed to evaluate overall similarity between images…

Flexibility in Statistical Word Segmentation: Finding Words in Foreign Speech

ERIC Educational Resources Information Center

Graf Estes, Katharine; Gluck, Stephanie Chen-Wu; Bastos, Carolina

2015-01-01

The present experiments investigated the flexibility of statistical word segmentation. There is ample evidence that infants can use statistical cues (e.g., syllable transitional probabilities) to segment fluent speech. However, it is unclear how effectively infants track these patterns in unfamiliar phonological systems. We examined whether…

Measuring the Success of an Academic Development Programme: A Statistical Analysis

ERIC Educational Resources Information Center

Smith, L. C.

2009-01-01

This study uses statistical analysis to estimate the impact of first-year academic development courses in microeconomics, statistics, accountancy, and information systems, offered by the University of Cape Town's Commerce Academic Development Programme, on students' graduation performance relative to that achieved by mainstream students. The data…

Material Phase Causality or a Dynamics-Statistical Interpretation of Quantum Mechanics

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

Koprinkov, I. G.

2010-11-25

The internal phase dynamics of a quantum system interacting with an electromagnetic field is revealed in details. Theoretical and experimental evidences of a causal relation of the phase of the wave function to the dynamics of the quantum system are presented sistematically for the first time. A dynamics-statistical interpretation of the quantum mechanics is introduced.

Single-molecule photon emission statistics for systems with explicit time dependence: Generating function approach

NASA Astrophysics Data System (ADS)

Peng, Yonggang; Xie, Shijie; Zheng, Yujun; Brown, Frank L. H.

2009-12-01

Generating function calculations are extended to allow for laser pulse envelopes of arbitrary shape in numerical applications. We investigate photon emission statistics for two-level and V- and Λ-type three-level systems under time-dependent excitation. Applications relevant to electromagnetically induced transparency and photon emission from single quantum dots are presented.

Assessing and Measuring Statistics Cognition in Higher Education Online Environments: Emerging Research and Opportunities

ERIC Educational Resources Information Center

Chase, Justin P.; Yan, Zheng

2017-01-01

The ability to effective learn, process, and retain new information is critical to the success of any student. Since mathematics are becoming increasingly more important in our educational systems, it is imperative that we devise an efficient system to measure these types of information recall. "Assessing and Measuring Statistics Cognition in…

Statistical Supplement to the Annual Report of the Coordinating Board, Texas College and University System for Fiscal Year 1978.

ERIC Educational Resources Information Center

Ashworth, Kenneth H.

This supplement to the 1978 Annual Report of the Coordinating Board, Texas College and University System, contains comprehensive statistical data on higher education in Texas. The supplement provides facts, figures, and formulas relating to student enrollments and faculty headcounts, program development and productivity, faculty salaries and…

Parameterizing Phrase Based Statistical Machine Translation Models: An Analytic Study

ERIC Educational Resources Information Center

Cer, Daniel

2011-01-01

The goal of this dissertation is to determine the best way to train a statistical machine translation system. I first develop a state-of-the-art machine translation system called Phrasal and then use it to examine a wide variety of potential learning algorithms and optimization criteria and arrive at two very surprising results. First, despite the…

Application of binomial and multinomial probability statistics to the sampling design process of a global grain tracing and recall system

USDA-ARS?s Scientific Manuscript database

Small, coded, pill-sized tracers embedded in grain are proposed as a method for grain traceability. A sampling process for a grain traceability system was designed and investigated by applying probability statistics using a science-based sampling approach to collect an adequate number of tracers fo...

Modelling Complexity: Making Sense of Leadership Issues in 14-19 Education

ERIC Educational Resources Information Center

Briggs, Ann R. J.

2008-01-01

Modelling of statistical data is a well established analytical strategy. Statistical data can be modelled to represent, and thereby predict, the forces acting upon a structure or system. For the rapidly changing systems in the world of education, modelling enables the researcher to understand, to predict and to enable decisions to be based upon…

System Analysis for the Huntsville Operation Support Center, Distributed Computer System

NASA Technical Reports Server (NTRS)

Ingels, F. M.; Massey, D.

1985-01-01

HOSC as a distributed computing system, is responsible for data acquisition and analysis during Space Shuttle operations. HOSC also provides computing services for Marshall Space Flight Center's nonmission activities. As mission and nonmission activities change, so do the support functions of HOSC change, demonstrating the need for some method of simulating activity at HOSC in various configurations. The simulation developed in this work primarily models the HYPERchannel network. The model simulates the activity of a steady state network, reporting statistics such as, transmitted bits, collision statistics, frame sequences transmitted, and average message delay. These statistics are used to evaluate such performance indicators as throughout, utilization, and delay. Thus the overall performance of the network is evaluated, as well as predicting possible overload conditions.

Statistical crossover characterization of the heterotic localized-extended transition.

PubMed

Ugajin, Ryuichi

2003-07-01

We investigated the spectral statistics of a quantum particle in a superlattice consisting of a disordered layer and a clean layer, possibly accompanied by random magnetic fields. Because a disordered layer has localized states and a clean layer has extended states, our quantum system shows a heterotic phase of an Anderson insulator and a normal metal. As the ratio of the volume of these two layers changes, the spectral statistics change from Poissonian to one of the Gaussian ensembles which characterize quantum chaos. A crossover distribution specified by two parameters is introduced to distinguish the transition from an integrable system to a quantum chaotic system during the heterotic phase from an Anderson transition in which the degree of random potentials is homogenous.

Management system of occupational diseases in Korea: statistics, report and monitoring system.

PubMed

Rhee, Kyung Yong; Choe, Seong Weon

2010-12-01

The management system of occupational diseases in Korea can be assessed from the perspective of a surveillance system. Workers' compensation insurance reports are used to produce official statistics on occupational diseases in Korea. National working conditions surveys are used to monitor the magnitude of work-related symptoms and signs in the labor force. A health examination program was introduced to detect occupational diseases through both selective and mass screening programs. The Working Environment Measurement Institution assesses workers' exposure to hazards in the workplace. Government regulates that the employer should do health examinations and working conditions measurement through contracted private agencies and following the Occupational Safety and Health Act. It is hoped that these institutions may be able to effectively detect and monitor occupational diseases and hazards in the workplace. In view of this, the occupational management system in Korea is well designed, except for the national survey system. In the future, national surveys for detection of hazards and ill-health outcomes in workers should be developed. The existing surveillance system for occupational disease can be improved by providing more refined information through statistical analysis of surveillance data.

CRN5EXP: Expert system for statistical quality control

NASA Technical Reports Server (NTRS)

Hentea, Mariana

1991-01-01

The purpose of the Expert System CRN5EXP is to assist in checking the quality of the coils at two very important mills: Hot Rolling and Cold Rolling in a steel plant. The system interprets the statistical quality control charts, diagnoses and predicts the quality of the steel. Measurements of process control variables are recorded in a database and sample statistics such as the mean and the range are computed and plotted on a control chart. The chart is analyzed through patterns using the C Language Integrated Production System (CLIPS) and a forward chaining technique to reach a conclusion about the causes of defects and to take management measures for the improvement of the quality control techniques. The Expert System combines the certainty factors associated with the process control variables to predict the quality of the steel. The paper presents the approach to extract data from the database, the reason to combine certainty factors, the architecture and the use of the Expert System. However, the interpretation of control charts patterns requires the human expert's knowledge and lends to Expert Systems rules.

Statistical Mechanics of Disordered Systems - Series: Cambridge Series in Statistical and Probabilistic Mathematics (No. 18)

NASA Astrophysics Data System (ADS)

Bovier, Anton

2006-06-01

Our mathematical understanding of the statistical mechanics of disordered systems is going through a period of stunning progress. This self-contained book is a graduate-level introduction for mathematicians and for physicists interested in the mathematical foundations of the field, and can be used as a textbook for a two-semester course on mathematical statistical mechanics. It assumes only basic knowledge of classical physics and, on the mathematics side, a good working knowledge of graduate-level probability theory. The book starts with a concise introduction to statistical mechanics, proceeds to disordered lattice spin systems, and concludes with a presentation of the latest developments in the mathematical understanding of mean-field spin glass models. In particular, recent progress towards a rigorous understanding of the replica symmetry-breaking solutions of the Sherrington-Kirkpatrick spin glass models, due to Guerra, Aizenman-Sims-Starr and Talagrand, is reviewed in some detail. Comprehensive introduction to an active and fascinating area of research Clear exposition that builds to the state of the art in the mathematics of spin glasses Written by a well-known and active researcher in the field

"The Two Brothers": Reconciling Perceptual-Cognitive and Statistical Models of Musical Evolution.

PubMed

Jan, Steven

2018-01-01

While the "units, events and dynamics" of memetic evolution have been abstractly theorized (Lynch, 1998), they have not been applied systematically to real corpora in music. Some researchers, convinced of the validity of cultural evolution in more than the metaphorical sense adopted by much musicology, but perhaps skeptical of some or all of the claims of memetics, have attempted statistically based corpus-analysis techniques of music drawn from molecular biology, and these have offered strong evidence in favor of system-level change over time (Savage, 2017). This article argues that such statistical approaches, while illuminating, ignore the psychological realities of music-information grouping, the transmission of such groups with varying degrees of fidelity, their selection according to relative perceptual-cognitive salience, and the power of this Darwinian process to drive the systemic changes (such as the development over time of systems of tonal organization in music) that statistical methodologies measure. It asserts that a synthesis between such statistical approaches to the study of music-cultural change and the theory of memetics as applied to music (Jan, 2007), in particular the latter's perceptual-cognitive elements, would harness the strengths of each approach and deepen understanding of cultural evolution in music.

“The Two Brothers”: Reconciling Perceptual-Cognitive and Statistical Models of Musical Evolution

PubMed Central

Jan, Steven

2018-01-01

While the “units, events and dynamics” of memetic evolution have been abstractly theorized (Lynch, 1998), they have not been applied systematically to real corpora in music. Some researchers, convinced of the validity of cultural evolution in more than the metaphorical sense adopted by much musicology, but perhaps skeptical of some or all of the claims of memetics, have attempted statistically based corpus-analysis techniques of music drawn from molecular biology, and these have offered strong evidence in favor of system-level change over time (Savage, 2017). This article argues that such statistical approaches, while illuminating, ignore the psychological realities of music-information grouping, the transmission of such groups with varying degrees of fidelity, their selection according to relative perceptual-cognitive salience, and the power of this Darwinian process to drive the systemic changes (such as the development over time of systems of tonal organization in music) that statistical methodologies measure. It asserts that a synthesis between such statistical approaches to the study of music-cultural change and the theory of memetics as applied to music (Jan, 2007), in particular the latter's perceptual-cognitive elements, would harness the strengths of each approach and deepen understanding of cultural evolution in music. PMID:29670551

Infectious bursal disease: seroprevalence and associated risk factors in major poultry rearing areas of Ethiopia.

PubMed

Jenbreie, Shiferaw; Ayelet, Gelagay; Gelaye, Esayas; Kebede, Fekadu; Lynch, Stacey E; Negussie, Haileleul

2013-01-01

The study was conducted in eight districts of Ethiopia with the objectives of determining the seroprevalence and associated risk factors of infectious bursal disease (IBD). From the total of 2,597 chicken serum samples examined using ELISA, 83.1 % were found positive. The highest seroprevalence was found at Mekele (90.3 %) while the lowest was recorded at Gondar district (69.8 %). These differences among the study areas were statistically significant (p < 0.05). Highest seroprevalence was found in crossbreed of chicken (91.4 %) while the lowest was recorded in indigenous breed of chicken (81.4 %). This difference was statistically significant (p < 0.05) among the three breeds of chickens, but sex was not statistically significant (p > 0.05). The seroprevalence of the disease was found high in young (≤ 8 weeks) age group (86.6 %) while the lowest prevalence was recorded in adults (>8 weeks) (72 %). This is also statistically significant (p < 0.05) between young and adult age groups. The prevalence of IBD in different production system indicated that higher seroprevalence was recorded in intensive production system (85.9 %) while the lowest was recorded in extensive production system (81.6 %). This difference is also statistically significant (p < 0.05).

Gaussian orthogonal ensemble statistics in graphene billiards with the shape of classically integrable billiards.

PubMed

Yu, Pei; Li, Zi-Yuan; Xu, Hong-Ya; Huang, Liang; Dietz, Barbara; Grebogi, Celso; Lai, Ying-Cheng

2016-12-01

A crucial result in quantum chaos, which has been established for a long time, is that the spectral properties of classically integrable systems generically are described by Poisson statistics, whereas those of time-reversal symmetric, classically chaotic systems coincide with those of random matrices from the Gaussian orthogonal ensemble (GOE). Does this result hold for two-dimensional Dirac material systems? To address this fundamental question, we investigate the spectral properties in a representative class of graphene billiards with shapes of classically integrable circular-sector billiards. Naively one may expect to observe Poisson statistics, which is indeed true for energies close to the band edges where the quasiparticle obeys the Schrödinger equation. However, for energies near the Dirac point, where the quasiparticles behave like massless Dirac fermions, Poisson statistics is extremely rare in the sense that it emerges only under quite strict symmetry constraints on the straight boundary parts of the sector. An arbitrarily small amount of imperfection of the boundary results in GOE statistics. This implies that, for circular-sector confinements with arbitrary angle, the spectral properties will generically be GOE. These results are corroborated by extensive numerical computation. Furthermore, we provide a physical understanding for our results.

Gaussian orthogonal ensemble statistics in graphene billiards with the shape of classically integrable billiards

NASA Astrophysics Data System (ADS)

Yu, Pei; Li, Zi-Yuan; Xu, Hong-Ya; Huang, Liang; Dietz, Barbara; Grebogi, Celso; Lai, Ying-Cheng

2016-12-01

A crucial result in quantum chaos, which has been established for a long time, is that the spectral properties of classically integrable systems generically are described by Poisson statistics, whereas those of time-reversal symmetric, classically chaotic systems coincide with those of random matrices from the Gaussian orthogonal ensemble (GOE). Does this result hold for two-dimensional Dirac material systems? To address this fundamental question, we investigate the spectral properties in a representative class of graphene billiards with shapes of classically integrable circular-sector billiards. Naively one may expect to observe Poisson statistics, which is indeed true for energies close to the band edges where the quasiparticle obeys the Schrödinger equation. However, for energies near the Dirac point, where the quasiparticles behave like massless Dirac fermions, Poisson statistics is extremely rare in the sense that it emerges only under quite strict symmetry constraints on the straight boundary parts of the sector. An arbitrarily small amount of imperfection of the boundary results in GOE statistics. This implies that, for circular-sector confinements with arbitrary angle, the spectral properties will generically be GOE. These results are corroborated by extensive numerical computation. Furthermore, we provide a physical understanding for our results.

Evaluation of Active Mortality Surveillance System Data for Monitoring Hurricane-Related Deaths—Texas, 2008

PubMed Central

Choudhary, Ekta; Zane, David F.; Beasley, Crystal; Jones, Russell; Rey, Araceli; Noe, Rebecca S.; Martin, Colleen; Wolkin, Amy F.; Bayleyegn, Tesfaye M.

2015-01-01

Introduction The Texas Department of State Health Services (DSHS) implemented an active mortality surveillance system to enumerate and characterize hurricane-related deaths during Hurricane Ike in 2008. This surveillance system used established guidelines and case definitions to categorize deaths as directly, indirectly, and possibly related to Hurricane Ike. Objective The objective of this study was to evaluate Texas DSHS’ active mortality surveillance system using US Centers for Disease Control and Prevention’s (CDC) surveillance system evaluation guidelines. Methods Using CDC’s Updated Guidelines for Surveillance System Evaluation, the active mortality surveillance system of the Texas DSHS was evaluated. Data from the active mortality surveillance system were compared with Texas vital statistics data for the same time period to estimate the completeness of reported disaster-related deaths. Results From September 8 through October 13, 2008, medical examiners (MEs) and Justices of the Peace (JPs) in 44 affected counties reported deaths daily by using a one-page, standardized mortality form. The active mortality surveillance system identified 74 hurricane-related deaths, whereas a review of vital statistics data revealed only four deaths that were hurricane-related. The average time of reporting a death by active mortality surveillance and vital statistics was 14 days and 16 days, respectively. Conclusions Texas’s active mortality surveillance system successfully identified hurricane-related deaths. Evaluation of the active mortality surveillance system suggested that it is necessary to collect detailed and representative mortality data during a hurricane because vital statistics do not capture sufficient information to identify whether deaths are hurricane-related. The results from this evaluation will help improve active mortality surveillance during hurricanes which, in turn, will enhance preparedness and response plans and identify public health interventions to reduce future hurricane-related mortality rates. PMID:22800916

Evaluation of active mortality surveillance system data for monitoring hurricane-related deaths-Texas, 2008.

PubMed

Choudhary, Ekta; Zane, David F; Beasley, Crystal; Jones, Russell; Rey, Araceli; Noe, Rebecca S; Martin, Colleen; Wolkin, Amy F; Bayleyegn, Tesfaye M

2012-08-01

The Texas Department of State Health Services (DSHS) implemented an active mortality surveillance system to enumerate and characterize hurricane-related deaths during Hurricane Ike in 2008. This surveillance system used established guidelines and case definitions to categorize deaths as directly, indirectly, and possibly related to Hurricane Ike. The objective of this study was to evaluate Texas DSHS' active mortality surveillance system using US Centers for Disease Control and Prevention's (CDC) surveillance system evaluation guidelines. Using CDC's Updated Guidelines for Surveillance System Evaluation, the active mortality surveillance system of the Texas DSHS was evaluated. Data from the active mortality surveillance system were compared with Texas vital statistics data for the same time period to estimate the completeness of reported disaster-related deaths. From September 8 through October 13, 2008, medical examiners (MEs) and Justices of the Peace (JPs) in 44 affected counties reported deaths daily by using a one-page, standardized mortality form. The active mortality surveillance system identified 74 hurricane-related deaths, whereas a review of vital statistics data revealed only four deaths that were hurricane-related. The average time of reporting a death by active mortality surveillance and vital statistics was 14 days and 16 days, respectively. Texas's active mortality surveillance system successfully identified hurricane-related deaths. Evaluation of the active mortality surveillance system suggested that it is necessary to collect detailed and representative mortality data during a hurricane because vital statistics do not capture sufficient information to identify whether deaths are hurricane-related. The results from this evaluation will help improve active mortality surveillance during hurricanes which, in turn, will enhance preparedness and response plans and identify public health interventions to reduce future hurricane-related mortality rates.

Integrating community-based verbal autopsy into civil registration and vital statistics (CRVS): system-level considerations

PubMed Central

de Savigny, Don; Riley, Ian; Chandramohan, Daniel; Odhiambo, Frank; Nichols, Erin; Notzon, Sam; AbouZahr, Carla; Mitra, Raj; Cobos Muñoz, Daniel; Firth, Sonja; Maire, Nicolas; Sankoh, Osman; Bronson, Gay; Setel, Philip; Byass, Peter; Jakob, Robert; Boerma, Ties; Lopez, Alan D.

2017-01-01

ABSTRACT Background: Reliable and representative cause of death (COD) statistics are essential to inform public health policy, respond to emerging health needs, and document progress towards Sustainable Development Goals. However, less than one-third of deaths worldwide are assigned a cause. Civil registration and vital statistics (CRVS) systems in low- and lower-middle-income countries are failing to provide timely, complete and accurate vital statistics, and it will still be some time before they can provide physician-certified COD for every death. Proposals: Verbal autopsy (VA) is a method to ascertain the probable COD and, although imperfect, it is the best alternative in the absence of medical certification. There is extensive experience with VA in research settings but only a few examples of its use on a large scale. Data collection using electronic questionnaires on mobile devices and computer algorithms to analyse responses and estimate probable COD have increased the potential for VA to be routinely applied in CRVS systems. However, a number of CRVS and health system integration issues should be considered in planning, piloting and implementing a system-wide intervention such as VA. These include addressing the multiplicity of stakeholders and sub-systems involved, integration with existing CRVS work processes and information flows, linking VA results to civil registration records, information technology requirements and data quality assurance. Conclusions: Integrating VA within CRVS systems is not simply a technical undertaking. It will have profound system-wide effects that should be carefully considered when planning for an effective implementation. This paper identifies and discusses the major system-level issues and emerging practices, provides a planning checklist of system-level considerations and proposes an overview for how VA can be integrated into routine CRVS systems. PMID:28137194

A Statistical Study on Neutron Star Masses

NASA Astrophysics Data System (ADS)

Cheng, Z.; Zhang, C. M.; Zhao, Y. H.; Wang, D. H.; Pan, Y. Y.; Lei, Y. J.

2013-11-01

We investigate the measurement of neutron star masses in different population of binaries. Based on the collection of the orbital parameters of 40 systems (46 sources), we apply the boot-strap method together with the Monte Carlo method to reconstruct the likelihood curves for each source separately. The cumulative analysis of the simulation result shows that the neutron star masses in X-ray systems and radio systems obey different distributions, and no evidence for the bimodal distribution could be found. Employing the Bayesian statistical techniques, we find that the most likely distributions for the high mass X-ray binaries (HMXBs), low mass X-ray binaries (LMXBs), double neutron star (DNS) systems, and neutron star-white dwarf (NS-WD) binary systems are (1.340±0.230) M_{⊙}, (1.505±0.125) M_{⊙}, (1.335±0.055) M_{⊙}, and (1.495±0.225) M_{⊙}, respectively. The statistical distribution has no significant deviation from the standard neutron star formation mechanism. It is noticed that the statistical results of the center masses of LMXBs and NS-WD systems are significantly higher than the other groups by about 0.16 M_{⊙}, which could be regarded as the evidence of accretion episodes. And if we regard the HMXBs and LMXBs as the progenitors of DNS and NS-WD systems, then we can draw the conclusion that the accretion effect must be very week during the evolution trajectory from HMXBs to DNS systems, and this could be the reason why the masses of DNS systems have such a narrow distribution.

Statistical similarities of pre-earthquake electromagnetic emissions to biological and economic extreme events

NASA Astrophysics Data System (ADS)

Potirakis, Stelios M.; Contoyiannis, Yiannis; Kopanas, John; Kalimeris, Anastasios; Antonopoulos, George; Peratzakis, Athanasios; Eftaxias, Konstantinos; Nomicos, Costantinos

2014-05-01

When one considers a phenomenon that is "complex" refers to a system whose phenomenological laws that describe the global behavior of the system, are not necessarily directly related to the "microscopic" laws that regulate the evolution of its elementary parts. The field of study of complex systems considers that the dynamics of complex systems are founded on universal principles that may be used to describe disparate problems ranging from particle physics to economies of societies. Several authors have suggested that earthquake (EQ) dynamics can be analyzed within similar mathematical frameworks with economy dynamics, and neurodynamics. A central property of the EQ preparation process is the occurrence of coherent large-scale collective behavior with a very rich structure, resulting from repeated nonlinear interactions among the constituents of the system. As a result, nonextensive statistics is an appropriate, physically meaningful, tool for the study of EQ dynamics. Since the fracture induced electromagnetic (EM) precursors are observable manifestations of the underlying EQ preparation process, the analysis of a fracture induced EM precursor observed prior to the occurrence of a large EQ can also be conducted within the nonextensive statistics framework. Within the frame of the investigation for universal principles that may hold for different dynamical systems that are related to the genesis of extreme events, we present here statistical similarities of the pre-earthquake EM emissions related to an EQ, with the pre-ictal electrical brain activity related to an epileptic seizure, and with the pre-crisis economic observables related to the collapse of a share. It is demonstrated the all three dynamical systems' observables can be analyzed in the frame of nonextensive statistical mechanics, while the frequency-size relations of appropriately defined "events" that precede the extreme event related to each one of these different systems present striking quantitative similarities. It is also demonstrated that, for the considered systems, the nonextensive parameter q increases as the extreme event approaches, which indicates that the strength of the long-memory / long-range interactions between the constituents of the system increases characterizing the dynamics of the system.

Analysis of Professional and Pre-Accession Characteristics and Junior Naval Officer Performance

DTIC Science & Technology

2018-03-01

REVIEW .............................................5 A. NAVY PERFORMANCE EVALUATION SYSTEM ............................5 B. PROFESSIONAL...17 A. DATA DESCRIPTION ...........................................................................17 B. SUMMARY...STATISTICS ......................................................................24 C. DESCRIPTIVE STATISTICS

The role of ensemble-based statistics in variational assimilation of cloud-affected observations from infrared imagers

NASA Astrophysics Data System (ADS)

Hacker, Joshua; Vandenberghe, Francois; Jung, Byoung-Jo; Snyder, Chris

2017-04-01

Effective assimilation of cloud-affected radiance observations from space-borne imagers, with the aim of improving cloud analysis and forecasting, has proven to be difficult. Large observation biases, nonlinear observation operators, and non-Gaussian innovation statistics present many challenges. Ensemble-variational data assimilation (EnVar) systems offer the benefits of flow-dependent background error statistics from an ensemble, and the ability of variational minimization to handle nonlinearity. The specific benefits of ensemble statistics, relative to static background errors more commonly used in variational systems, have not been quantified for the problem of assimilating cloudy radiances. A simple experiment framework is constructed with a regional NWP model and operational variational data assimilation system, to provide the basis understanding the importance of ensemble statistics in cloudy radiance assimilation. Restricting the observations to those corresponding to clouds in the background forecast leads to innovations that are more Gaussian. The number of large innovations is reduced compared to the more general case of all observations, but not eliminated. The Huber norm is investigated to handle the fat tails of the distributions, and allow more observations to be assimilated without the need for strict background checks that eliminate them. Comparing assimilation using only ensemble background error statistics with assimilation using only static background error statistics elucidates the importance of the ensemble statistics. Although the cost functions in both experiments converge to similar values after sufficient outer-loop iterations, the resulting cloud water, ice, and snow content are greater in the ensemble-based analysis. The subsequent forecasts from the ensemble-based analysis also retain more condensed water species, indicating that the local environment is more supportive of clouds. In this presentation we provide details that explain the apparent benefit from using ensembles for cloudy radiance assimilation in an EnVar context.

Streamstats: U.S. Geological Survey Web Application for Streamflow Statistics for Connecticut

USGS Publications Warehouse

Ahearn, Elizabeth A.; Ries, Kernell G.; Steeves, Peter A.

2006-01-01

Introduction An important mission of the U. S. Geological Survey (USGS) is to provide information on streamflow in the Nation's rivers. Streamflow statistics are used by water managers, engineers, scientists, and others to protect people and property during floods and droughts, and to manage land, water, and biological resources. Common uses for streamflow statistics include dam, bridge, and culvert design; water-supply planning and management; water-use appropriations and permitting; wastewater and industrial discharge permitting; hydropower-facility design and regulation; and flood-plain mapping for establishing flood-insurance rates and land-use zones. In an effort to improve access to published streamflow statistics, and to make the process of computing streamflow statistics for ungaged stream sites easier, more accurate, and more consistent, the USGS and the Environmental Systems Research Institute, Inc. (ESRI) developed StreamStats (Ries and others, 2004). StreamStats is a Geographic Information System (GIS)-based Web application for serving previously published streamflow statistics and basin characteristics for USGS data-collection stations, and computing streamflow statistics and basin characteristics for ungaged stream sites. The USGS, in cooperation with the Connecticut Department of Environmental Protection and the Connecticut Department of Transportation, has implemented StreamStats for Connecticut.

System Study: Emergency Power System 1998-2014

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

Schroeder, John Alton

2015-12-01

This report presents an unreliability evaluation of the emergency power system (EPS) at 104 U.S. commercial nuclear power plants. Demand, run hours, and failure data from fiscal year 1998 through 2014 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10 year period while yearly estimates for system unreliability are provided for the entire active period. An extremely statistically significant increasing trend was observed for EPS system unreliability for an 8-hour mission. A statistically significant increasing trend was observed for EPS system start-onlymore » unreliability.« less

The writer independent online handwriting recognition system frog on hand and cluster generative statistical dynamic time warping.

PubMed

Bahlmann, Claus; Burkhardt, Hans

2004-03-01

In this paper, we give a comprehensive description of our writer-independent online handwriting recognition system frog on hand. The focus of this work concerns the presentation of the classification/training approach, which we call cluster generative statistical dynamic time warping (CSDTW). CSDTW is a general, scalable, HMM-based method for variable-sized, sequential data that holistically combines cluster analysis and statistical sequence modeling. It can handle general classification problems that rely on this sequential type of data, e.g., speech recognition, genome processing, robotics, etc. Contrary to previous attempts, clustering and statistical sequence modeling are embedded in a single feature space and use a closely related distance measure. We show character recognition experiments of frog on hand using CSDTW on the UNIPEN online handwriting database. The recognition accuracy is significantly higher than reported results of other handwriting recognition systems. Finally, we describe the real-time implementation of frog on hand on a Linux Compaq iPAQ embedded device.

Metrological traceability in education: A practical online system for measuring and managing middle school mathematics instruction

NASA Astrophysics Data System (ADS)

Torres Irribarra, D.; Freund, R.; Fisher, W.; Wilson, M.

2015-02-01

Computer-based, online assessments modelled, designed, and evaluated for adaptively administered invariant measurement are uniquely suited to defining and maintaining traceability to standardized units in education. An assessment of this kind is embedded in the Assessing Data Modeling and Statistical Reasoning (ADM) middle school mathematics curriculum. Diagnostic information about middle school students' learning of statistics and modeling is provided via computer-based formative assessments for seven constructs that comprise a learning progression for statistics and modeling from late elementary through the middle school grades. The seven constructs are: Data Display, Meta-Representational Competence, Conceptions of Statistics, Chance, Modeling Variability, Theory of Measurement, and Informal Inference. The end product is a web-delivered system built with Ruby on Rails for use by curriculum development teams working with classroom teachers in designing, developing, and delivering formative assessments. The online accessible system allows teachers to accurately diagnose students' unique comprehension and learning needs in a common language of real-time assessment, logging, analysis, feedback, and reporting.

Development of modelling algorithm of technological systems by statistical tests

NASA Astrophysics Data System (ADS)

Shemshura, E. A.; Otrokov, A. V.; Chernyh, V. G.

2018-03-01

The paper tackles the problem of economic assessment of design efficiency regarding various technological systems at the stage of their operation. The modelling algorithm of a technological system was performed using statistical tests and with account of the reliability index allows estimating the level of machinery technical excellence and defining the efficiency of design reliability against its performance. Economic feasibility of its application shall be determined on the basis of service quality of a technological system with further forecasting of volumes and the range of spare parts supply.

LP-search and its use in analysis of the accuracy of control systems with acoustical models

NASA Technical Reports Server (NTRS)

Sergeyev, V. I.; Sobol, I. M.; Statnikov, R. B.; Statnikov, I. N.

1973-01-01

The LP-search is proposed as an analog of the Monte Carlo method for finding values in nonlinear statistical systems. It is concluded that: To attain the required accuracy in solution to the problem of control for a statistical system in the LP-search, a considerably smaller number of tests is required than in the Monte Carlo method. The LP-search allows the possibility of multiple repetitions of tests under identical conditions and observability of the output variables of the system.

Ergodicity in natural earthquake fault networks

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

Tiampo, K. F.; Rundle, J. B.; Holliday, J.

2007-06-15

Numerical simulations have shown that certain driven nonlinear systems can be characterized by mean-field statistical properties often associated with ergodic dynamics [C. D. Ferguson, W. Klein, and J. B. Rundle, Phys. Rev. E 60, 1359 (1999); D. Egolf, Science 287, 101 (2000)]. These driven mean-field threshold systems feature long-range interactions and can be treated as equilibriumlike systems with statistically stationary dynamics over long time intervals. Recently the equilibrium property of ergodicity was identified in an earthquake fault system, a natural driven threshold system, by means of the Thirumalai-Mountain (TM) fluctuation metric developed in the study of diffusive systems [K. F.more » Tiampo, J. B. Rundle, W. Klein, J. S. Sa Martins, and C. D. Ferguson, Phys. Rev. Lett. 91, 238501 (2003)]. We analyze the seismicity of three naturally occurring earthquake fault networks from a variety of tectonic settings in an attempt to investigate the range of applicability of effective ergodicity, using the TM metric and other related statistics. Results suggest that, once variations in the catalog data resulting from technical and network issues are accounted for, all of these natural earthquake systems display stationary periods of metastable equilibrium and effective ergodicity that are disrupted by large events. We conclude that a constant rate of events is an important prerequisite for these periods of punctuated ergodicity and that, while the level of temporal variability in the spatial statistics is the controlling factor in the ergodic behavior of seismic networks, no single statistic is sufficient to ensure quantification of ergodicity. Ergodicity in this application not only requires that the system be stationary for these networks at the applicable spatial and temporal scales, but also implies that they are in a state of metastable equilibrium, one in which the ensemble averages can be substituted for temporal averages in studying their spatiotemporal evolution.« less

Reaction Event Counting Statistics of Biopolymer Reaction Systems with Dynamic Heterogeneity.

PubMed

Lim, Yu Rim; Park, Seong Jun; Park, Bo Jung; Cao, Jianshu; Silbey, Robert J; Sung, Jaeyoung

2012-04-10

We investigate the reaction event counting statistics (RECS) of an elementary biopolymer reaction in which the rate coefficient is dependent on states of the biopolymer and the surrounding environment and discover a universal kinetic phase transition in the RECS of the reaction system with dynamic heterogeneity. From an exact analysis for a general model of elementary biopolymer reactions, we find that the variance in the number of reaction events is dependent on the square of the mean number of the reaction events when the size of measurement time is small on the relaxation time scale of rate coefficient fluctuations, which does not conform to renewal statistics. On the other hand, when the size of the measurement time interval is much greater than the relaxation time of rate coefficient fluctuations, the variance becomes linearly proportional to the mean reaction number in accordance with renewal statistics. Gillespie's stochastic simulation method is generalized for the reaction system with a rate coefficient fluctuation. The simulation results confirm the correctness of the analytic results for the time dependent mean and variance of the reaction event number distribution. On the basis of the obtained results, we propose a method of quantitative analysis for the reaction event counting statistics of reaction systems with rate coefficient fluctuations, which enables one to extract information about the magnitude and the relaxation times of the fluctuating reaction rate coefficient, without a bias that can be introduced by assuming a particular kinetic model of conformational dynamics and the conformation dependent reactivity. An exact relationship is established between a higher moment of the reaction event number distribution and the multitime correlation of the reaction rate for the reaction system with a nonequilibrium initial state distribution as well as for the system with the equilibrium initial state distribution.

Traversing the conceptual divide between biological and statistical epistasis: systems biology and a more modern synthesis.

PubMed

Moore, Jason H; Williams, Scott M

2005-06-01

Epistasis plays an important role in the genetic architecture of common human diseases and can be viewed from two perspectives, biological and statistical, each derived from and leading to different assumptions and research strategies. Biological epistasis is the result of physical interactions among biomolecules within gene regulatory networks and biochemical pathways in an individual such that the effect of a gene on a phenotype is dependent on one or more other genes. In contrast, statistical epistasis is defined as deviation from additivity in a mathematical model summarizing the relationship between multilocus genotypes and phenotypic variation in a population. The goal of this essay is to review definitions and examples of biological and statistical epistasis and to explore the relationship between the two. Specifically, we present and discuss the following two questions in the context of human health and disease. First, when does statistical evidence of epistasis in human populations imply underlying biomolecular interactions in the etiology of disease? Second, when do biomolecular interactions produce patterns of statistical epistasis in human populations? Answers to these two reciprocal questions will provide an important framework for using genetic information to improve our ability to diagnose, prevent and treat common human diseases. We propose that systems biology will provide the necessary information for addressing these questions and that model systems such as bacteria, yeast and digital organisms will be a useful place to start.

Loop Braiding Statistics and Interacting Fermionic Symmetry-Protected Topological Phases in Three Dimensions

NASA Astrophysics Data System (ADS)

Cheng, Meng; Tantivasadakarn, Nathanan; Wang, Chenjie

2018-01-01

We study Abelian braiding statistics of loop excitations in three-dimensional gauge theories with fermionic particles and the closely related problem of classifying 3D fermionic symmetry-protected topological (FSPT) phases with unitary symmetries. It is known that the two problems are related by turning FSPT phases into gauge theories through gauging the global symmetry of the former. We show that there exist certain types of Abelian loop braiding statistics that are allowed only in the presence of fermionic particles, which correspond to 3D "intrinsic" FSPT phases, i.e., those that do not stem from bosonic SPT phases. While such intrinsic FSPT phases are ubiquitous in 2D systems and in 3D systems with antiunitary symmetries, their existence in 3D systems with unitary symmetries was not confirmed previously due to the fact that strong interaction is necessary to realize them. We show that the simplest unitary symmetry to support 3D intrinsic FSPT phases is Z2×Z4. To establish the results, we first derive a complete set of physical constraints on Abelian loop braiding statistics. Solving the constraints, we obtain all possible Abelian loop braiding statistics in 3D gauge theories, including those that correspond to intrinsic FSPT phases. Then, we construct exactly soluble state-sum models to realize the loop braiding statistics. These state-sum models generalize the well-known Crane-Yetter and Dijkgraaf-Witten models.

Application of Tube Dynamics to Non-Statistical Reaction Processes

NASA Astrophysics Data System (ADS)

Gabern, F.; Koon, W. S.; Marsden, J. E.; Ross, S. D.; Yanao, T.

2006-06-01

A technique based on dynamical systems theory is introduced for the computation of lifetime distributions and rates of chemical reactions and scattering phenomena, even in systems that exhibit non-statistical behavior. In particular, we merge invariant manifold tube dynamics with Monte Carlo volume determination for accurate rate calculations. This methodology is applied to a three-degree-of-freedom model problem and some ideas on how it might be extended to higher-degree-of-freedom systems are presented.

PET image reconstruction: a robust state space approach.

PubMed

Liu, Huafeng; Tian, Yi; Shi, Pengcheng

2005-01-01

Statistical iterative reconstruction algorithms have shown improved image quality over conventional nonstatistical methods in PET by using accurate system response models and measurement noise models. Strictly speaking, however, PET measurements, pre-corrected for accidental coincidences, are neither Poisson nor Gaussian distributed and thus do not meet basic assumptions of these algorithms. In addition, the difficulty in determining the proper system response model also greatly affects the quality of the reconstructed images. In this paper, we explore the usage of state space principles for the estimation of activity map in tomographic PET imaging. The proposed strategy formulates the organ activity distribution through tracer kinetics models, and the photon-counting measurements through observation equations, thus makes it possible to unify the dynamic reconstruction problem and static reconstruction problem into a general framework. Further, it coherently treats the uncertainties of the statistical model of the imaging system and the noisy nature of measurement data. Since H(infinity) filter seeks minimummaximum-error estimates without any assumptions on the system and data noise statistics, it is particular suited for PET image reconstruction where the statistical properties of measurement data and the system model are very complicated. The performance of the proposed framework is evaluated using Shepp-Logan simulated phantom data and real phantom data with favorable results.

A new universality class in corpus of texts; A statistical physics study

NASA Astrophysics Data System (ADS)

Najafi, Elham; Darooneh, Amir H.

2018-05-01

Text can be regarded as a complex system. There are some methods in statistical physics which can be used to study this system. In this work, by means of statistical physics methods, we reveal new universal behaviors of texts associating with the fractality values of words in a text. The fractality measure indicates the importance of words in a text by considering distribution pattern of words throughout the text. We observed a power law relation between fractality of text and vocabulary size for texts and corpora. We also observed this behavior in studying biological data.

Statistics of the work done on a quantum critical system by quenching a control parameter.

PubMed

Silva, Alessandro

2008-09-19

We study the statistics of the work done on a quantum critical system by quenching a control parameter in the Hamiltonian. We elucidate the relation between the probability distribution of the work and the Loschmidt echo, a quantity emerging usually in the context of dephasing. Using this connection we characterize the statistics of the work done on a quantum Ising chain by quenching locally or globally the transverse field. We show that for local quenches starting at criticality the probability distribution of the work displays an interesting edge singularity.

Chaotic oscillations and noise transformations in a simple dissipative system with delayed feedback

NASA Astrophysics Data System (ADS)

Zverev, V. V.; Rubinstein, B. Ya.

1991-04-01

We analyze the statistical behavior of signals in nonlinear circuits with delayed feedback in the presence of external Markovian noise. For the special class of circuits with intense phase mixing we develop an approach for the computation of the probability distributions and multitime correlation functions based on the random phase approximation. Both Gaussian and Kubo-Andersen models of external noise statistics are analyzed and the existence of the stationary (asymptotic) random process in the long-time limit is shown. We demonstrate that a nonlinear system with chaotic behavior becomes a noise amplifier with specific statistical transformation properties.

A Not-So-Fundamental Limitation on Studying Complex Systems with Statistics: Comment on Rabin (2011)

NASA Astrophysics Data System (ADS)

Thomas, Drew M.

2012-12-01

Although living organisms are affected by many interrelated and unidentified variables, this complexity does not automatically impose a fundamental limitation on statistical inference. Nor need one invoke such complexity as an explanation of the "Truth Wears Off" or "decline" effect; similar "decline" effects occur with far simpler systems studied in physics. Selective reporting and publication bias, and scientists' biases in favor of reporting eye-catching results (in general) or conforming to others' results (in physics) better explain this feature of the "Truth Wears Off" effect than Rabin's suggested limitation on statistical inference.

Long-term strategy for the statistical design of a forest health monitoring system

Treesearch

Hans T. Schreuder; Raymond L. Czaplewski

1993-01-01

A conceptual framework is given for a broad-scale survey of forest health that accomplishes three objectives: generate descriptive statistics; detect changes in such statistics; and simplify analytical inferences that identify, and possibly establish cause-effect relationships. Our paper discusses the development of sampling schemes to satisfy these three objectives,...

Decision Support Systems: Applications in Statistics and Hypothesis Testing.

ERIC Educational Resources Information Center

Olsen, Christopher R.; Bozeman, William C.

1988-01-01

Discussion of the selection of appropriate statistical procedures by educators highlights a study conducted to investigate the effectiveness of decision aids in facilitating the use of appropriate statistics. Experimental groups and a control group using a printed flow chart, a computer-based decision aid, and a standard text are described. (11…

Use of Management Statistics in ARL Libraries. SPEC Kit #153.

ERIC Educational Resources Information Center

Vasi, John

A Systems and Procedures Exchange Center (SPEC) survey conducted in 1986 investigated the collection and use of management statistics in Association of Research Libraries (ARL) member libraries, and SPEC Kit #134 (May 1987) summarized the kinds of statistics collected and the reasons given by the 91 respondents for collecting them. This more…

78 FR 16365 - Foreign Trade Regulations: Mandatory Automated Export System Filing for All Shipments Requiring...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-14

... collecting, compiling, and publishing export trade statistics for the United States under the provisions of... for collecting export trade data, which is used by the Census Bureau for statistical purposes only... timely statistics as well as address the enforcement and security concerns of CBP, the Bureau of Industry...

Computers as an Instrument for Data Analysis. Technical Report No. 11.

ERIC Educational Resources Information Center

Muller, Mervin E.

A review of statistical data analysis involving computers as a multi-dimensional problem provides the perspective for consideration of the use of computers in statistical analysis and the problems associated with large data files. An overall description of STATJOB, a particular system for doing statistical data analysis on a digital computer,…

A Constructivist Approach in a Blended E-Learning Environment for Statistics

ERIC Educational Resources Information Center

Poelmans, Stephan; Wessa, Patrick

2015-01-01

In this study, we report on the students' evaluation of a self-constructed constructivist e-learning environment for statistics, the compendium platform (CP). The system was built to endorse deeper learning with the incorporation of statistical reproducibility and peer review practices. The deployment of the CP, with interactive workshops and…

The Effect of "Clickers" on Attendance in an Introductory Statistics Course: An Action Research Study

ERIC Educational Resources Information Center

Amstelveen, Raoul H.

2013-01-01

The purpose of this study was to design and implement a Classroom Response System, also known as a "clicker," to increase attendance in introductory statistics courses at an undergraduate university. Since 2010, non-attendance had been prevalent in introductory statistics courses. Moreover, non-attendance created undesirable classrooms…

Statistics of natural movements are reflected in motor errors.

PubMed

Howard, Ian S; Ingram, James N; Körding, Konrad P; Wolpert, Daniel M

2009-09-01

Humans use their arms to engage in a wide variety of motor tasks during everyday life. However, little is known about the statistics of these natural arm movements. Studies of the sensory system have shown that the statistics of sensory inputs are key to determining sensory processing. We hypothesized that the statistics of natural everyday movements may, in a similar way, influence motor performance as measured in laboratory-based tasks. We developed a portable motion-tracking system that could be worn by subjects as they went about their daily routine outside of a laboratory setting. We found that the well-documented symmetry bias is reflected in the relative incidence of movements made during everyday tasks. Specifically, symmetric and antisymmetric movements are predominant at low frequencies, whereas only symmetric movements are predominant at high frequencies. Moreover, the statistics of natural movements, that is, their relative incidence, correlated with subjects' performance on a laboratory-based phase-tracking task. These results provide a link between natural movement statistics and motor performance and confirm that the symmetry bias documented in laboratory studies is a natural feature of human movement.

Asymptotic inference in system identification for the atom maser.

PubMed

Catana, Catalin; van Horssen, Merlijn; Guta, Madalin

2012-11-28

System identification is closely related to control theory and plays an increasing role in quantum engineering. In the quantum set-up, system identification is usually equated to process tomography, i.e. estimating a channel by probing it repeatedly with different input states. However, for quantum dynamical systems such as quantum Markov processes, it is more natural to consider the estimation based on continuous measurements of the output, with a given input that may be stationary. We address this problem using asymptotic statistics tools, for the specific example of estimating the Rabi frequency of an atom maser. We compute the Fisher information of different measurement processes as well as the quantum Fisher information of the atom maser, and establish the local asymptotic normality of these statistical models. The statistical notions can be expressed in terms of spectral properties of certain deformed Markov generators, and the connection to large deviations is briefly discussed.

Compounding approach for univariate time series with nonstationary variances

NASA Astrophysics Data System (ADS)

Schäfer, Rudi; Barkhofen, Sonja; Guhr, Thomas; Stöckmann, Hans-Jürgen; Kuhl, Ulrich

2015-12-01

A defining feature of nonstationary systems is the time dependence of their statistical parameters. Measured time series may exhibit Gaussian statistics on short time horizons, due to the central limit theorem. The sample statistics for long time horizons, however, averages over the time-dependent variances. To model the long-term statistical behavior, we compound the local distribution with the distribution of its parameters. Here, we consider two concrete, but diverse, examples of such nonstationary systems: the turbulent air flow of a fan and a time series of foreign exchange rates. Our main focus is to empirically determine the appropriate parameter distribution for the compounding approach. To this end, we extract the relevant time scales by decomposing the time signals into windows and determine the distribution function of the thus obtained local variances.

Compounding approach for univariate time series with nonstationary variances.

PubMed

Schäfer, Rudi; Barkhofen, Sonja; Guhr, Thomas; Stöckmann, Hans-Jürgen; Kuhl, Ulrich

2015-12-01

A defining feature of nonstationary systems is the time dependence of their statistical parameters. Measured time series may exhibit Gaussian statistics on short time horizons, due to the central limit theorem. The sample statistics for long time horizons, however, averages over the time-dependent variances. To model the long-term statistical behavior, we compound the local distribution with the distribution of its parameters. Here, we consider two concrete, but diverse, examples of such nonstationary systems: the turbulent air flow of a fan and a time series of foreign exchange rates. Our main focus is to empirically determine the appropriate parameter distribution for the compounding approach. To this end, we extract the relevant time scales by decomposing the time signals into windows and determine the distribution function of the thus obtained local variances.

Capturing every patron interaction: the move from paper statistics to an electronic system to track the whole library.

PubMed

Vardell, Emily; Loper, Kimberly; Vaidhyanathan, Vedana

2012-01-01

Reference departments track patron interactions to illustrate the type and number of services provided as well as to tailor librarians' time and expertise to the interest and needs of their patrons. Until 2010 the Reference, Education, and Community Engagement Department at the Calder Memorial Library tracked statistics using a complicated system of paper tic sheets and two Excel™ spreadsheets. After considering different electronic systems, the department decided to employ an electronic form created with SurveyMonkey™ to track patron interactions. After the system had been in place for three months, the authors administered a satisfaction and use survey to collect faculty and staff feedback on the new system. Seven months later the authors undertook usability testing to collect further evaluative data on the electronic form. The patron interaction form continues to be used to collect statistics, provide data for annual reviews, and recognize the contributions of all faculty and staff at the library.

FR0CAT: a FIRST catalog of FR 0 radio galaxies

NASA Astrophysics Data System (ADS)

Baldi, R. D.; Capetti, A.; Massaro, F.

2018-01-01

With the aim of exploring the properties of the class of FR 0 radio galaxies, we selected a sample of 108 compact radio sources, called FR0CAT, by combining observations from the NVSS, FIRST, and SDSS surveys. We included in the catalog sources with redshift ≤0.05, with a radio size ≲5 kpc, and with an optical spectrum characteristic of low-excitation galaxies. Their radio luminosities at 1.4 GHz are in the range 1038 ≲ νL1.4 ≲ 1040 erg s-1. The FR0CAT hosts are mostly (86%) luminous (-21 ≳ Mr ≳ -23) red early-type galaxies with black hole masses 108 ≲ MBH ≲ 109M⊙. These properties are similar to those seen for the hosts of FR I radio galaxies, but they are on average a factor 1.6 less massive. The number density of FR0CAT sources is 5 times higher than that of FR Is, and thus they represent the dominant population of radio sources in the local Universe. Different scenarios are considered to account for the smaller sizes and larger abundance of FR 0s with respect to FR Is. An age-size scenario that considers FR 0s as young radio galaxies that will all eventually evolve into extended radio sources cannot be reconciled with the large space density of FR 0s. However, the radio activity recurrence, with the duration of the active phase covering a wide range of values and with short active periods strongly favored with respect to longer ones, might account for their large density number. Alternatively, the jet properties of FR 0s might be intrinsically different from those of the FR Is, the former class having lower bulk Lorentz factors, possibly due to lower black hole spins. Our study indicates that FR 0s and FR I/IIs can be interpreted as two extremes of a continuous population of radio sources that is characterized by a broad distribution of sizes and luminosities of their extended radio emission, but shares a single class of host galaxies.

1976-77 California Public Schools Selected Statistics: Operating Units, Revenues, Teachers and Pupils, Expenditures.

ERIC Educational Resources Information Center

California State Dept. of Education, Sacramento. Bureau of School Apportionments and Reports.

Statistics on the California school system presented in this publication are prerequisites to the determination of policy at the state and local levels. This publication lists the number of pupils, teachers, and schools in the California school system and associated programs in the 1976-77 school year. It also records the expenditures of public…

Trends in Teenage Childbearing, United States, 1970-81. Data from the National Vital Statistics System.

ERIC Educational Resources Information Center

Ventura, Stephanie J.

1984-01-01

This report describes trends and differentials in births and birth rates for teenagers since 1970, and examines the demographic characteristics of the mothers and the health of their newborn children. A brief introduction and a review of highlights of the findings from National Vital Statistics System data is followed by discussions in several…

Statistics of City School Systems, 1927-28. Bulletin, 1929, No. 34

ERIC Educational Resources Information Center

Office of Education, United States Department of the Interior, 1929

1929-01-01

This report contains statistics of city public-school systems for the school year ending in June 1928. Certain data are given in detail for all cities having a population of 10,000 and more and summary tables are included for all cities having a population of 2,500 and more. The United States Census Bureau classification of cities is used…

On the Stability of Jump-Linear Systems Driven by Finite-State Machines with Markovian Inputs

NASA Technical Reports Server (NTRS)

Patilkulkarni, Sudarshan; Herencia-Zapana, Heber; Gray, W. Steven; Gonzalez, Oscar R.

2004-01-01

This paper presents two mean-square stability tests for a jump-linear system driven by a finite-state machine with a first-order Markovian input process. The first test is based on conventional Markov jump-linear theory and avoids the use of any higher-order statistics. The second test is developed directly using the higher-order statistics of the machine s output process. The two approaches are illustrated with a simple model for a recoverable computer control system.

Adapting an Agent-Based Model of Socio-Technical Systems to Analyze System and Security Failures

DTIC Science & Technology

2016-05-09

statistically significant amount, which it did with a p-valueɘ.0003 on a simulation of 3125 iterations; the data is shown in the Delegation 1 column of...Blackout metric to a statistically significant amount, with a p-valueɘ.0003 on a simulation of 3125 iterations; the data is shown in the Delegation 2...Proceedings of the 9th International Conference on Autonomous Agents and Multiagent Systems: volume 1-Volume 1, pp. 1007- 1014 . International Foundation

Subject-enabled analytics model on measurement statistics in health risk expert system for public health informatics.

PubMed

Chung, Chi-Jung; Kuo, Yu-Chen; Hsieh, Yun-Yu; Li, Tsai-Chung; Lin, Cheng-Chieh; Liang, Wen-Miin; Liao, Li-Na; Li, Chia-Ing; Lin, Hsueh-Chun

2017-11-01

This study applied open source technology to establish a subject-enabled analytics model that can enhance measurement statistics of case studies with the public health data in cloud computing. The infrastructure of the proposed model comprises three domains: 1) the health measurement data warehouse (HMDW) for the case study repository, 2) the self-developed modules of online health risk information statistics (HRIStat) for cloud computing, and 3) the prototype of a Web-based process automation system in statistics (PASIS) for the health risk assessment of case studies with subject-enabled evaluation. The system design employed freeware including Java applications, MySQL, and R packages to drive a health risk expert system (HRES). In the design, the HRIStat modules enforce the typical analytics methods for biomedical statistics, and the PASIS interfaces enable process automation of the HRES for cloud computing. The Web-based model supports both modes, step-by-step analysis and auto-computing process, respectively for preliminary evaluation and real time computation. The proposed model was evaluated by computing prior researches in relation to the epidemiological measurement of diseases that were caused by either heavy metal exposures in the environment or clinical complications in hospital. The simulation validity was approved by the commercial statistics software. The model was installed in a stand-alone computer and in a cloud-server workstation to verify computing performance for a data amount of more than 230K sets. Both setups reached efficiency of about 10 5 sets per second. The Web-based PASIS interface can be used for cloud computing, and the HRIStat module can be flexibly expanded with advanced subjects for measurement statistics. The analytics procedure of the HRES prototype is capable of providing assessment criteria prior to estimating the potential risk to public health. Copyright © 2017 Elsevier B.V. All rights reserved.

Computational algebraic geometry for statistical modeling FY09Q2 progress.

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

Thompson, David C.; Rojas, Joseph Maurice; Pebay, Philippe Pierre

2009-03-01

This is a progress report on polynomial system solving for statistical modeling. This is a progress report on polynomial system solving for statistical modeling. This quarter we have developed our first model of shock response data and an algorithm for identifying the chamber cone containing a polynomial system in n variables with n+k terms within polynomial time - a significant improvement over previous algorithms, all having exponential worst-case complexity. We have implemented and verified the chamber cone algorithm for n+3 and are working to extend the implementation to handle arbitrary k. Later sections of this report explain chamber cones inmore » more detail; the next section provides an overview of the project and how the current progress fits into it.« less

Defining the ecological hydrology of Taiwan Rivers using multivariate statistical methods

NASA Astrophysics Data System (ADS)

Chang, Fi-John; Wu, Tzu-Ching; Tsai, Wen-Ping; Herricks, Edwin E.

2009-09-01

SummaryThe identification and verification of ecohydrologic flow indicators has found new support as the importance of ecological flow regimes is recognized in modern water resources management, particularly in river restoration and reservoir management. An ecohydrologic indicator system reflecting the unique characteristics of Taiwan's water resources and hydrology has been developed, the Taiwan ecohydrological indicator system (TEIS). A major challenge for the water resources community is using the TEIS to provide environmental flow rules that improve existing water resources management. This paper examines data from the extensive network of flow monitoring stations in Taiwan using TEIS statistics to define and refine environmental flow options in Taiwan. Multivariate statistical methods were used to examine TEIS statistics for 102 stations representing the geographic and land use diversity of Taiwan. The Pearson correlation coefficient showed high multicollinearity between the TEIS statistics. Watersheds were separated into upper and lower-watershed locations. An analysis of variance indicated significant differences between upstream, more natural, and downstream, more developed, locations in the same basin with hydrologic indicator redundancy in flow change and magnitude statistics. Issues of multicollinearity were examined using a Principal Component Analysis (PCA) with the first three components related to general flow and high/low flow statistics, frequency and time statistics, and quantity statistics. These principle components would explain about 85% of the total variation. A major conclusion is that managers must be aware of differences among basins, as well as differences within basins that will require careful selection of management procedures to achieve needed flow regimes.

Health Statistics NSW: getting the right balance between privacy and small numbers in a web-based reporting system.

PubMed

Scandol, James P; Moore, Helen A

2012-01-01

Health Statistics NSW is a new web-based application developed by the Centre for Epidemiology and Research at the NSW Ministry of Health. The application is designed to be an efficient vehicle for the timely delivery of health statistics to a diverse audience including the general public, health planners, researchers, students and policy analysts. The development and implementation of this web application required the consideration of a series of competing demands such as: the public interest in providing health data while maintaining the privacy interests of the individuals whose health is being reported; reporting data at spatial scales of relevance to health planners while maintaining the statistical integrity of any inferences drawn; the use of hardware and software systems which are publicly accessible, scalable and robust, while ensuring high levels of security. These three competing demands and the relationships between them are discussed in the context of Health Statistics NSW.

Sensitivity analysis of helicopter IMC decelerating steep approach and landing performance to navigation system parameters

NASA Technical Reports Server (NTRS)

Karmali, M. S.; Phatak, A. V.

1982-01-01

Results of a study to investigate, by means of a computer simulation, the performance sensitivity of helicopter IMC DSAL operations as a function of navigation system parameters are presented. A mathematical model representing generically a navigation system is formulated. The scenario simulated consists of a straight in helicopter approach to landing along a 6 deg glideslope. The deceleration magnitude chosen is 03g. The navigation model parameters are varied and the statistics of the total system errors (TSE) computed. These statistics are used to determine the critical navigation system parameters that affect the performance of the closed-loop navigation, guidance and control system of a UH-1H helicopter.

Phase transitions in the first-passage time of scale-invariant correlated processes

PubMed Central

Carretero-Campos, Concepción; Bernaola-Galván, Pedro; Ch. Ivanov, Plamen

2012-01-01

A key quantity describing the dynamics of complex systems is the first-passage time (FPT). The statistical properties of FPT depend on the specifics of the underlying system dynamics. We present a unified approach to account for the diversity of statistical behaviors of FPT observed in real-world systems. We find three distinct regimes, separated by two transition points, with fundamentally different behavior for FPT as a function of increasing strength of the correlations in the system dynamics: stretched exponential, power-law, and saturation regimes. In the saturation regime, the average length of FPT diverges proportionally to the system size, with important implications for understanding electronic delocalization in one-dimensional correlated-disordered systems. PMID:22400544

Statistics and Epidemiology of Lead Poisoning (FY 72-L1).

ERIC Educational Resources Information Center

Morrison, John H., Jr.; And Others

This report is the first in a quarterly series which will contain statistics and epidemiologic notes on lead poisoning at both the national and local levels. This report contains (a) statistics on childhood lead poisoning; (b) a status report on the Community Lead Poisoning Data System, which was designed to assist local lead control programs and…

SSD for R: A Comprehensive Statistical Package to Analyze Single-System Data

ERIC Educational Resources Information Center

Auerbach, Charles; Schudrich, Wendy Zeitlin

2013-01-01

The need for statistical analysis in single-subject designs presents a challenge, as analytical methods that are applied to group comparison studies are often not appropriate in single-subject research. "SSD for R" is a robust set of statistical functions with wide applicability to single-subject research. It is a comprehensive package…

Using DEWIS and R for Multi-Staged Statistics e-Assessments

ERIC Educational Resources Information Center

Gwynllyw, D. Rhys; Weir, Iain S.; Henderson, Karen L.

2016-01-01

We demonstrate how the DEWIS e-Assessment system may use embedded R code to facilitate the assessment of students' ability to perform involved statistical analyses. The R code has been written to emulate SPSS output and thus the statistical results for each bespoke data set can be generated efficiently and accurately using standard R routines.…

What We Know about Community College Low-Income and Minority Student Outcomes: Descriptive Statistics from National Surveys

ERIC Educational Resources Information Center

Bailey, Thomas; Jenkins, Davis; Leinbach, Timothy

2005-01-01

This report summarizes the latest available national statistics on access and attainment by low income and minority community college students. The data come from the National Center for Education Statistics' (NCES) Integrated Postsecondary Education Data System (IPEDS) annual surveys of all postsecondary educational institutions and the NCES…

Schools and Staffing Survey (SASS). Papers Presented at Meetings of the American Statistical Association. Working Paper Series.

ERIC Educational Resources Information Center

National Center for Education Statistics (ED), Washington, DC.

The Schools and Staffing Survey (SASS) is an integrated system of surveys of public and private schools, school districts, school administrators, and teachers conducted by the National Center for Education Statistics (NCES). This collection contains papers related to the SASS presented at meetings of the American Statistical Association in August…

SEER Cancer Query Systems (CanQues)

Cancer.gov

These applications provide access to cancer statistics including incidence, mortality, survival, prevalence, and probability of developing or dying from cancer. Users can display reports of the statistics or extract them for additional analyses.

Application of the Linux cluster for exhaustive window haplotype analysis using the FBAT and Unphased programs.

PubMed

Mishima, Hiroyuki; Lidral, Andrew C; Ni, Jun

2008-05-28

Genetic association studies have been used to map disease-causing genes. A newly introduced statistical method, called exhaustive haplotype association study, analyzes genetic information consisting of different numbers and combinations of DNA sequence variations along a chromosome. Such studies involve a large number of statistical calculations and subsequently high computing power. It is possible to develop parallel algorithms and codes to perform the calculations on a high performance computing (HPC) system. However, most existing commonly-used statistic packages for genetic studies are non-parallel versions. Alternatively, one may use the cutting-edge technology of grid computing and its packages to conduct non-parallel genetic statistical packages on a centralized HPC system or distributed computing systems. In this paper, we report the utilization of a queuing scheduler built on the Grid Engine and run on a Rocks Linux cluster for our genetic statistical studies. Analysis of both consecutive and combinational window haplotypes was conducted by the FBAT (Laird et al., 2000) and Unphased (Dudbridge, 2003) programs. The dataset consisted of 26 loci from 277 extended families (1484 persons). Using the Rocks Linux cluster with 22 compute-nodes, FBAT jobs performed about 14.4-15.9 times faster, while Unphased jobs performed 1.1-18.6 times faster compared to the accumulated computation duration. Execution of exhaustive haplotype analysis using non-parallel software packages on a Linux-based system is an effective and efficient approach in terms of cost and performance.

Application of the Linux cluster for exhaustive window haplotype analysis using the FBAT and Unphased programs

PubMed Central

Mishima, Hiroyuki; Lidral, Andrew C; Ni, Jun

2008-01-01

Background Genetic association studies have been used to map disease-causing genes. A newly introduced statistical method, called exhaustive haplotype association study, analyzes genetic information consisting of different numbers and combinations of DNA sequence variations along a chromosome. Such studies involve a large number of statistical calculations and subsequently high computing power. It is possible to develop parallel algorithms and codes to perform the calculations on a high performance computing (HPC) system. However, most existing commonly-used statistic packages for genetic studies are non-parallel versions. Alternatively, one may use the cutting-edge technology of grid computing and its packages to conduct non-parallel genetic statistical packages on a centralized HPC system or distributed computing systems. In this paper, we report the utilization of a queuing scheduler built on the Grid Engine and run on a Rocks Linux cluster for our genetic statistical studies. Results Analysis of both consecutive and combinational window haplotypes was conducted by the FBAT (Laird et al., 2000) and Unphased (Dudbridge, 2003) programs. The dataset consisted of 26 loci from 277 extended families (1484 persons). Using the Rocks Linux cluster with 22 compute-nodes, FBAT jobs performed about 14.4–15.9 times faster, while Unphased jobs performed 1.1–18.6 times faster compared to the accumulated computation duration. Conclusion Execution of exhaustive haplotype analysis using non-parallel software packages on a Linux-based system is an effective and efficient approach in terms of cost and performance. PMID:18541045

Performance evaluation of a hybrid-passive landfill leachate treatment system using multivariate statistical techniques

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

Wallace, Jack, E-mail: jack.wallace@ce.queensu.ca; Champagne, Pascale, E-mail: champagne@civil.queensu.ca; Monnier, Anne-Charlotte, E-mail: anne-charlotte.monnier@insa-lyon.fr

Highlights: • Performance of a hybrid passive landfill leachate treatment system was evaluated. • 33 Water chemistry parameters were sampled for 21 months and statistically analyzed. • Parameters were strongly linked and explained most (>40%) of the variation in data. • Alkalinity, ammonia, COD, heavy metals, and iron were criteria for performance. • Eight other parameters were key in modeling system dynamics and criteria. - Abstract: A pilot-scale hybrid-passive treatment system operated at the Merrick Landfill in North Bay, Ontario, Canada, treats municipal landfill leachate and provides for subsequent natural attenuation. Collected leachate is directed to a hybrid-passive treatment system,more » followed by controlled release to a natural attenuation zone before entering the nearby Little Sturgeon River. The study presents a comprehensive evaluation of the performance of the system using multivariate statistical techniques to determine the interactions between parameters, major pollutants in the leachate, and the biological and chemical processes occurring in the system. Five parameters (ammonia, alkalinity, chemical oxygen demand (COD), “heavy” metals of interest, with atomic weights above calcium, and iron) were set as criteria for the evaluation of system performance based on their toxicity to aquatic ecosystems and importance in treatment with respect to discharge regulations. System data for a full range of water quality parameters over a 21-month period were analyzed using principal components analysis (PCA), as well as principal components (PC) and partial least squares (PLS) regressions. PCA indicated a high degree of association for most parameters with the first PC, which explained a high percentage (>40%) of the variation in the data, suggesting strong statistical relationships among most of the parameters in the system. Regression analyses identified 8 parameters (set as independent variables) that were most frequently retained for modeling the five criteria parameters (set as dependent variables), on a statistically significant level: conductivity, dissolved oxygen (DO), nitrite (NO{sub 2}{sup −}), organic nitrogen (N), oxidation reduction potential (ORP), pH, sulfate and total volatile solids (TVS). The criteria parameters and the significant explanatory parameters were most important in modeling the dynamics of the passive treatment system during the study period. Such techniques and procedures were found to be highly valuable and could be applied to other sites to determine parameters of interest in similar naturalized engineered systems.« less

An Exploratory Data Analysis System for Support in Medical Decision-Making

PubMed Central

Copeland, J. A.; Hamel, B.; Bourne, J. R.

1979-01-01

An experimental system was developed to allow retrieval and analysis of data collected during a study of neurobehavioral correlates of renal disease. After retrieving data organized in a relational data base, simple bivariate statistics of parametric and nonparametric nature could be conducted. An “exploratory” mode in which the system provided guidance in selection of appropriate statistical analyses was also available to the user. The system traversed a decision tree using the inherent qualities of the data (e.g., the identity and number of patients, tests, and time epochs) to search for the appropriate analyses to employ.

System analysis for the Huntsville Operational Support Center distributed computer system

NASA Technical Reports Server (NTRS)

Ingels, E. M.

1983-01-01

A simulation model was developed and programmed in three languages BASIC, PASCAL, and SLAM. Two of the programs are included in this report, the BASIC and the PASCAL language programs. SLAM is not supported by NASA/MSFC facilities and hence was not included. The statistical comparison of simulations of the same HOSC system configurations are in good agreement and are in agreement with the operational statistics of HOSC that were obtained. Three variations of the most recent HOSC configuration was run and some conclusions drawn as to the system performance under these variations.

[Development and application of emergency medical information management system].

PubMed

Wang, Fang; Zhu, Baofeng; Chen, Jianrong; Wang, Jian; Gu, Chaoli; Liu, Buyun

2011-03-01

To meet the needs of clinical practice of rescuing critical illness and develop the information management system of the emergency medicine. Microsoft Visual FoxPro, which is one of Microsoft's visual programming tool, is used to develop computer-aided system included the information management system of the emergency medicine. The system mainly consists of the module of statistic analysis, the module of quality control of emergency rescue, the module of flow path of emergency rescue, the module of nursing care in emergency rescue, and the module of rescue training. It can realize the system management of emergency medicine and,process and analyze the emergency statistical data. This system is practical. It can optimize emergency clinical pathway, and meet the needs of clinical rescue.

REANALYSIS OF F-STATISTIC GRAVITATIONAL-WAVE SEARCHES WITH THE HIGHER CRITICISM STATISTIC

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

Bennett, M. F.; Melatos, A.; Delaigle, A.

2013-04-01

We propose a new method of gravitational-wave detection using a modified form of higher criticism, a statistical technique introduced by Donoho and Jin. Higher criticism is designed to detect a group of sparse, weak sources, none of which are strong enough to be reliably estimated or detected individually. We apply higher criticism as a second-pass method to synthetic F-statistic and C-statistic data for a monochromatic periodic source in a binary system and quantify the improvement relative to the first-pass methods. We find that higher criticism on C-statistic data is more sensitive by {approx}6% than the C-statistic alone under optimal conditionsmore » (i.e., binary orbit known exactly) and the relative advantage increases as the error in the orbital parameters increases. Higher criticism is robust even when the source is not monochromatic (e.g., phase-wandering in an accreting system). Applying higher criticism to a phase-wandering source over multiple time intervals gives a {approx}> 30% increase in detectability with few assumptions about the frequency evolution. By contrast, in all-sky searches for unknown periodic sources, which are dominated by the brightest source, second-pass higher criticism does not provide any benefits over a first-pass search.« less

Mississippi Public Library Statistics, 1998. The Annual Report of Mississippi Public Library Statistics, October 1, 1997 to September 30, 1998.

ERIC Educational Resources Information Center

Shurden, Lynn F., Comp.

The Mississippi Library Commission, which acquires and publishes usage data from each of the 46 public library systems and two independent public libraries in the state, reports the data presented in this publication to the Federal State Cooperative System (FSCS) for Public Library Data. First, a 2-year summary (1997-1998) for public library…

Test Bus Evaluation

DTIC Science & Technology

1998-04-01

selected is statistically based on the total number of faults and the failure rate distribution in the system under test. The fault set is also...implemented the BPM and system level emulation consolidation logic as well as statistics counters for cache misses and various bus transactions. These...instruction F22 Advanced Tactical Fighter FET Field Effect Transitor FF Flip-Flop FM Failures/Milhon hours C-3 FPGA Field Programmable Gate Array GET

Use Trends Indicated by Statistically Calibrated Recreational Sites in the National Forest System

Treesearch

Gary L. Tyre

1971-01-01

Trends in statistically sampled use of developed sites in the National Forest system indicate an average annual increase of 6.0 percent in the period 1966-69. The high variability of the measure precludes its use for projecting expected future use, but it can be important in gauging the credibility of annual use changes at both sampled and unsampled locations.

Student Enrollment, Full-time Equivalent (FTE), Staff/Faculty Information. Annual Statistical Report, 1997-98. Volume 33.

ERIC Educational Resources Information Center

North Carolina Community Coll. System, Raleigh.

This document contains statistical information for the academic year 1997-1998 collected from each of the 58 community colleges in North Carolina, as well as historical information for an 11-year period. This was the first year in which the North Carolina Community College System used the semester system. In addition, it was the first year of…

FAA statistical handbook of aviation

DOT National Transportation Integrated Search

1994-01-01

This report presents statistical information pertaining to the Federal Aviation Administration, the National Airspace System, Airports, Airport Activity, U.S. Civil Air Carrier Fleet, U.S. Civil Air Carrier Operating Data, Airmen, General Aviation Ai...

75 FR 41539 - Privacy Act Systems of Records Notice

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-16

... statistics and analytical studies in support of the function for which the records are collected and maintained, or for related work force studies. While published statistics and studies do not contain...

Transportation statistics annual report 2001

DOT National Transportation Integrated Search

2001-01-01

This eighth Transportation Statistics Annual Report (TSAR), like : those before it, provides data and analysis on the U.S. transportation : system: its extent and condition, relationship to the : nation's security and economic growth, safety aspects,...

7 CFR 785.8 - Reports by qualifying States receiving mediation grant funds.

Code of Federal Regulations, 2010 CFR

2010-01-01

... reliable statistical data as may be obtained from State statistical sources including the certified State's bar association, State Department of Agriculture, State court system or Better Business Bureau, or...

76 FR 43206 - Electronic Tariff Filing System (ETFS)

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-20

...) Working papers and statistical data. (1) Concurrently with the filing of any tariff change or tariff... explanation of how the working papers relate to that information. (2) All statistical studies must be...

Recurrence time statistics for finite size intervals

NASA Astrophysics Data System (ADS)

Altmann, Eduardo G.; da Silva, Elton C.; Caldas, Iberê L.

2004-12-01

We investigate the statistics of recurrences to finite size intervals for chaotic dynamical systems. We find that the typical distribution presents an exponential decay for almost all recurrence times except for a few short times affected by a kind of memory effect. We interpret this effect as being related to the unstable periodic orbits inside the interval. Although it is restricted to a few short times it changes the whole distribution of recurrences. We show that for systems with strong mixing properties the exponential decay converges to the Poissonian statistics when the width of the interval goes to zero. However, we alert that special attention to the size of the interval is required in order to guarantee that the short time memory effect is negligible when one is interested in numerically or experimentally calculated Poincaré recurrence time statistics.

Nonequilibrium Statistical Operator Method and Generalized Kinetic Equations

NASA Astrophysics Data System (ADS)

Kuzemsky, A. L.

2018-01-01

We consider some principal problems of nonequilibrium statistical thermodynamics in the framework of the Zubarev nonequilibrium statistical operator approach. We present a brief comparative analysis of some approaches to describing irreversible processes based on the concept of nonequilibrium Gibbs ensembles and their applicability to describing nonequilibrium processes. We discuss the derivation of generalized kinetic equations for a system in a heat bath. We obtain and analyze a damped Schrödinger-type equation for a dynamical system in a heat bath. We study the dynamical behavior of a particle in a medium taking the dissipation effects into account. We consider the scattering problem for neutrons in a nonequilibrium medium and derive a generalized Van Hove formula. We show that the nonequilibrium statistical operator method is an effective, convenient tool for describing irreversible processes in condensed matter.

Methods and apparatuses for information analysis on shared and distributed computing systems

DOEpatents

Bohn, Shawn J [Richland, WA; Krishnan, Manoj Kumar [Richland, WA; Cowley, Wendy E [Richland, WA; Nieplocha, Jarek [Richland, WA

2011-02-22

Apparatuses and computer-implemented methods for analyzing, on shared and distributed computing systems, information comprising one or more documents are disclosed according to some aspects. In one embodiment, information analysis can comprise distributing one or more distinct sets of documents among each of a plurality of processes, wherein each process performs operations on a distinct set of documents substantially in parallel with other processes. Operations by each process can further comprise computing term statistics for terms contained in each distinct set of documents, thereby generating a local set of term statistics for each distinct set of documents. Still further, operations by each process can comprise contributing the local sets of term statistics to a global set of term statistics, and participating in generating a major term set from an assigned portion of a global vocabulary.

Self-organization of cosmic radiation pressure instability. II - One-dimensional simulations

NASA Technical Reports Server (NTRS)

Hogan, Craig J.; Woods, Jorden

1992-01-01

The clustering of statistically uniform discrete absorbing particles moving solely under the influence of radiation pressure from uniformly distributed emitters is studied in a simple one-dimensional model. Radiation pressure tends to amplify statistical clustering in the absorbers; the absorbing material is swept into empty bubbles, the biggest bubbles grow bigger almost as they would in a uniform medium, and the smaller ones get crushed and disappear. Numerical simulations of a one-dimensional system are used to support the conjecture that the system is self-organizing. Simple statistics indicate that a wide range of initial conditions produce structure approaching the same self-similar statistical distribution, whose scaling properties follow those of the attractor solution for an isolated bubble. The importance of the process for large-scale structuring of the interstellar medium is briefly discussed.

Statistical modeling of software reliability

NASA Technical Reports Server (NTRS)

Miller, Douglas R.

1992-01-01

This working paper discusses the statistical simulation part of a controlled software development experiment being conducted under the direction of the System Validation Methods Branch, Information Systems Division, NASA Langley Research Center. The experiment uses guidance and control software (GCS) aboard a fictitious planetary landing spacecraft: real-time control software operating on a transient mission. Software execution is simulated to study the statistical aspects of reliability and other failure characteristics of the software during development, testing, and random usage. Quantification of software reliability is a major goal. Various reliability concepts are discussed. Experiments are described for performing simulations and collecting appropriate simulated software performance and failure data. This data is then used to make statistical inferences about the quality of the software development and verification processes as well as inferences about the reliability of software versions and reliability growth under random testing and debugging.

Management System of Occupational Diseases in Korea: Statistics, Report and Monitoring System

PubMed Central

Choe, Seong Weon

2010-01-01

The management system of occupational diseases in Korea can be assessed from the perspective of a surveillance system. Workers' compensation insurance reports are used to produce official statistics on occupational diseases in Korea. National working conditions surveys are used to monitor the magnitude of work-related symptoms and signs in the labor force. A health examination program was introduced to detect occupational diseases through both selective and mass screening programs. The Working Environment Measurement Institution assesses workers' exposure to hazards in the workplace. Government regulates that the employer should do health examinations and working conditions measurement through contracted private agencies and following the Occupational Safety and Health Act. It is hoped that these institutions may be able to effectively detect and monitor occupational diseases and hazards in the workplace. In view of this, the occupational management system in Korea is well designed, except for the national survey system. In the future, national surveys for detection of hazards and ill-health outcomes in workers should be developed. The existing surveillance system for occupational disease can be improved by providing more refined information through statistical analysis of surveillance data. PMID:21258584

Coherent Doppler lidar signal covariance including wind shear and wind turbulence

NASA Technical Reports Server (NTRS)

Frehlich, R. G.

1993-01-01

The performance of coherent Doppler lidar is determined by the statistics of the coherent Doppler signal. The derivation and calculation of the covariance of the Doppler lidar signal is presented for random atmospheric wind fields with wind shear. The random component is described by a Kolmogorov turbulence spectrum. The signal parameters are clarified for a general coherent Doppler lidar system. There are two distinct physical regimes: one where the transmitted pulse determines the signal statistics and the other where the wind field dominates the signal statistics. The Doppler shift of the signal is identified in terms of the wind field and system parameters.

Ballistic and diffusive dynamics in a two-dimensional ideal gas of macroscopic chaotic Faraday waves.

PubMed

Welch, Kyle J; Hastings-Hauss, Isaac; Parthasarathy, Raghuveer; Corwin, Eric I

2014-04-01

We have constructed a macroscopic driven system of chaotic Faraday waves whose statistical mechanics, we find, are surprisingly simple, mimicking those of a thermal gas. We use real-time tracking of a single floating probe, energy equipartition, and the Stokes-Einstein relation to define and measure a pseudotemperature and diffusion constant and then self-consistently determine a coefficient of viscous friction for a test particle in this pseudothermal gas. Because of its simplicity, this system can serve as a model for direct experimental investigation of nonequilibrium statistical mechanics, much as the ideal gas epitomizes equilibrium statistical mechanics.

A two-component rain model for the prediction of attenuation statistics

NASA Technical Reports Server (NTRS)

Crane, R. K.

1982-01-01

A two-component rain model has been developed for calculating attenuation statistics. In contrast to most other attenuation prediction models, the two-component model calculates the occurrence probability for volume cells or debris attenuation events. The model performed significantly better than the International Radio Consultative Committee model when used for predictions on earth-satellite paths. It is expected that the model will have applications in modeling the joint statistics required for space diversity system design, the statistics of interference due to rain scatter at attenuating frequencies, and the duration statistics for attenuation events.

[Analyses of segment motor function in patients with degenerative lumbar disease on the treatment of WavefleX dynamic stabilization system].

PubMed

Wu, Junsong; Du, Junhua; Jiang, Xiangyun; Wang, Quan; Li, Xigong; Du, Jingyu; Lin, Xiangjin

2014-06-17

To explore the changes of range-of-motion (ROM) in patients with degenerative lumbar disease on the treatment of WavefleX dynamic stabilization system and examine the postoperative lumbar regularity and tendency of ROM. Nine patients with degenerative lumbar disease on the treatment of WavefleX dynamic stabilization system were followed up with respect to ROMs at 5 timepoints within 12 months. Records of ROM were made for instrumented segments, adjacent segments and total lumbar. Compared with preoperation, ROMs in non-fusional segments with WavefleX dynamic stabilization system decreased statistical significantly (P < 0.05 or P < 0.01) at different timepoints; ROMs in adjacent segments increased at some levels without wide statistical significance. The exception was single L3/4 at Month 12 (P < 0.05) versus control group simultaneously at the levels of L3/4, L4/5 and L5/S1, ROMs decreased at Months 6 and 12 with wide statistical significance (P < 0.05 or P < 0.01). ROMs in total lumbar had statistical significant decrease (P < 0.01) in both group of non-fusional segments and hybrid group of non-fusion and fusion. The trends of continuous augments were observed during follow-ups. Statistically significant augments were also acquired at 4 timepoints as compared to control group (P < 0.01). The treatment of degenerative lumbar diseases with WavefleX dynamic stabilization system may limit excessive extension/inflexion and preserve some motor functions. Moreover, it can sustain physiological lordosis, decrease and transfer disc load in adjacent segments to prevent early degeneration of adjacent segment. Trends of motor function augment in total lumbar need to be confirmed during future long-term follow-ups.

Reserve Manpower Statistics, 1 January - 31 March 1986.

DTIC Science & Technology

1986-03-31

This is the first issue of Reserv’e Nztnpowe Statistics , a quarterly publication based upon data from the Reserve Components Common Personnel Data System...1.2~5 MI ’CROCOPY RESOLUTION TEST CHART NATIONAL BUREAU OF STANDARDS-1963-A ,iI M15 o Department of Defense RESERVE MANPOWER STATISTICS __ March 31...1986 GUARD JID I A* LECTE3I ___SEP 17 1986 it % Ii TA 9 WWto’ VubUd reIOWa jiW, ii~ Department of Defense Reserve Manpower Statistics March 31

Tunneling Statistics for Analysis of Spin-Readout Fidelity

NASA Astrophysics Data System (ADS)

Gorman, S. K.; He, Y.; House, M. G.; Keizer, J. G.; Keith, D.; Fricke, L.; Hile, S. J.; Broome, M. A.; Simmons, M. Y.

2017-09-01

We investigate spin and charge dynamics of a quantum dot of phosphorus atoms coupled to a radio-frequency single-electron transistor (SET) using full counting statistics. We show how the magnetic field plays a role in determining the bunching or antibunching tunneling statistics of the donor dot and SET system. Using the counting statistics, we show how to determine the lowest magnetic field where spin readout is possible. We then show how such a measurement can be used to investigate and optimize single-electron spin-readout fidelity.

Blended particle filters for large-dimensional chaotic dynamical systems

PubMed Central

Majda, Andrew J.; Qi, Di; Sapsis, Themistoklis P.

2014-01-01

A major challenge in contemporary data science is the development of statistically accurate particle filters to capture non-Gaussian features in large-dimensional chaotic dynamical systems. Blended particle filters that capture non-Gaussian features in an adaptively evolving low-dimensional subspace through particles interacting with evolving Gaussian statistics on the remaining portion of phase space are introduced here. These blended particle filters are constructed in this paper through a mathematical formalism involving conditional Gaussian mixtures combined with statistically nonlinear forecast models compatible with this structure developed recently with high skill for uncertainty quantification. Stringent test cases for filtering involving the 40-dimensional Lorenz 96 model with a 5-dimensional adaptive subspace for nonlinear blended filtering in various turbulent regimes with at least nine positive Lyapunov exponents are used here. These cases demonstrate the high skill of the blended particle filter algorithms in capturing both highly non-Gaussian dynamical features as well as crucial nonlinear statistics for accurate filtering in extreme filtering regimes with sparse infrequent high-quality observations. The formalism developed here is also useful for multiscale filtering of turbulent systems and a simple application is sketched below. PMID:24825886

76 FR 4001 - Foreign Trade Regulations (FTR): Mandatory Automated Export System Filing for All Shipments...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-21

... trade statistics for the United States under the provisions of Title 13, United States Code (U.S.C... used by the Census Bureau for statistical purposes only. Through the AES, the Census Bureau collects... statistical filing requirements for Foreign Trade Zone shipments via the e214 or paper 214A. In Sec. 30.54(b...

2012-2013 CAUT Almanac of Post-Secondary Education in Canada = 2012-2013 Almanach de l'enseignement postsecondaire au Canada de l'ACPPU

ERIC Educational Resources Information Center

Canadian Association of University Teachers, 2013

2013-01-01

In previous editions of the CAUT Almanac, data for provincial postsecondary education expenditures, total expenditures and university and college revenues and expenditures was reported from Statistics Canada's Financial Management System (FMS), which Statistics Canada last published for the 2008-2009 fiscal year. Statistics Canada will be adopting…

The Development of Official Social Statistics in Italy with a Life Quality Approach

ERIC Educational Resources Information Center

Sabbadini, Linda Laura

2011-01-01

The article covers the main steps of official statistics in the second half of the Nineties through the illustration of the transition from economic oriented official statistics to the quality of life approach. The system of the Multipurpose Surveys introduced in 1993 to give an answer to questions at social level and to provide indicators for…

Irreversibility and entanglement spectrum statistics in quantum circuits

NASA Astrophysics Data System (ADS)

Shaffer, Daniel; Chamon, Claudio; Hamma, Alioscia; Mucciolo, Eduardo R.

2014-12-01

We show that in a quantum system evolving unitarily under a stochastic quantum circuit the notions of irreversibility, universality of computation, and entanglement are closely related. As the state evolves from an initial product state, it gets asymptotically maximally entangled. We define irreversibility as the failure of searching for a disentangling circuit using a Metropolis-like algorithm. We show that irreversibility corresponds to Wigner-Dyson statistics in the level spacing of the entanglement eigenvalues, and that this is obtained from a quantum circuit made from a set of universal gates for quantum computation. If, on the other hand, the system is evolved with a non-universal set of gates, the statistics of the entanglement level spacing deviates from Wigner-Dyson and the disentangling algorithm succeeds. These results open a new way to characterize irreversibility in quantum systems.

Bell Correlations in a Many-Body System with Finite Statistics

NASA Astrophysics Data System (ADS)

Wagner, Sebastian; Schmied, Roman; Fadel, Matteo; Treutlein, Philipp; Sangouard, Nicolas; Bancal, Jean-Daniel

2017-10-01

A recent experiment reported the first violation of a Bell correlation witness in a many-body system [Science 352, 441 (2016)]. Following discussions in this Letter, we address here the question of the statistics required to witness Bell correlated states, i.e., states violating a Bell inequality, in such experiments. We start by deriving multipartite Bell inequalities involving an arbitrary number of measurement settings, two outcomes per party and one- and two-body correlators only. Based on these inequalities, we then build up improved witnesses able to detect Bell correlated states in many-body systems using two collective measurements only. These witnesses can potentially detect Bell correlations in states with an arbitrarily low amount of spin squeezing. We then establish an upper bound on the statistics needed to convincingly conclude that a measured state is Bell correlated.

Bell Correlations in a Many-Body System with Finite Statistics.

PubMed

Wagner, Sebastian; Schmied, Roman; Fadel, Matteo; Treutlein, Philipp; Sangouard, Nicolas; Bancal, Jean-Daniel

2017-10-27

A recent experiment reported the first violation of a Bell correlation witness in a many-body system [Science 352, 441 (2016)]. Following discussions in this Letter, we address here the question of the statistics required to witness Bell correlated states, i.e., states violating a Bell inequality, in such experiments. We start by deriving multipartite Bell inequalities involving an arbitrary number of measurement settings, two outcomes per party and one- and two-body correlators only. Based on these inequalities, we then build up improved witnesses able to detect Bell correlated states in many-body systems using two collective measurements only. These witnesses can potentially detect Bell correlations in states with an arbitrarily low amount of spin squeezing. We then establish an upper bound on the statistics needed to convincingly conclude that a measured state is Bell correlated.

Advanced statistical energy analysis

NASA Astrophysics Data System (ADS)

Heron, K. H.

1994-09-01

A high-frequency theory (advanced statistical energy analysis (ASEA)) is developed which takes account of the mechanism of tunnelling and uses a ray theory approach to track the power flowing around a plate or a beam network and then uses statistical energy analysis (SEA) to take care of any residual power. ASEA divides the energy of each sub-system into energy that is freely available for transfer to other sub-systems and energy that is fixed within the sub-systems that are physically separate and can be interpreted as a series of mathematical models, the first of which is identical to standard SEA and subsequent higher order models are convergent on an accurate prediction. Using a structural assembly of six rods as an example, ASEA is shown to converge onto the exact results while SEA is shown to overpredict by up to 60 dB.

Validating an Air Traffic Management Concept of Operation Using Statistical Modeling

NASA Technical Reports Server (NTRS)

He, Yuning; Davies, Misty Dawn

2013-01-01

Validating a concept of operation for a complex, safety-critical system (like the National Airspace System) is challenging because of the high dimensionality of the controllable parameters and the infinite number of states of the system. In this paper, we use statistical modeling techniques to explore the behavior of a conflict detection and resolution algorithm designed for the terminal airspace. These techniques predict the robustness of the system simulation to both nominal and off-nominal behaviors within the overall airspace. They also can be used to evaluate the output of the simulation against recorded airspace data. Additionally, the techniques carry with them a mathematical value of the worth of each prediction-a statistical uncertainty for any robustness estimate. Uncertainty Quantification (UQ) is the process of quantitative characterization and ultimately a reduction of uncertainties in complex systems. UQ is important for understanding the influence of uncertainties on the behavior of a system and therefore is valuable for design, analysis, and verification and validation. In this paper, we apply advanced statistical modeling methodologies and techniques on an advanced air traffic management system, namely the Terminal Tactical Separation Assured Flight Environment (T-TSAFE). We show initial results for a parameter analysis and safety boundary (envelope) detection in the high-dimensional parameter space. For our boundary analysis, we developed a new sequential approach based upon the design of computer experiments, allowing us to incorporate knowledge from domain experts into our modeling and to determine the most likely boundary shapes and its parameters. We carried out the analysis on system parameters and describe an initial approach that will allow us to include time-series inputs, such as the radar track data, into the analysis

Surgical outcomes of total laparoscopic hysterectomy with 2-dimensional versus 3-dimensional laparoscopic surgical systems.

PubMed

Yazawa, Hiroyuki; Takiguchi, Kaoru; Imaizumi, Karin; Wada, Marina; Ito, Fumihiro

2018-04-17

Three-dimensional (3D) laparoscopic surgical systems have been developed to account for the lack of depth perception, a known disadvantage of conventional 2-dimensional (2D) laparoscopy. In this study, we retrospectively compared the outcomes of total laparoscopic hysterectomy (TLH) with 3D versus conventional 2D laparoscopy. From November 2014, when we began using a 3D laparoscopic system at our hospital, to December 2015, 47 TLH procedures were performed using a 3D laparoscopic system (3D-TLH). The outcomes of 3D-TLH were compared with the outcomes of TLH using the conventional 2D laparoscopic system (2D-TLH) performed just before the introduction of the 3D system. The 3D-TLH group had a statistically significantly shorter mean operative time than the 2D-TLH group (119±20 vs. 137±20 min), whereas the mean weight of the resected uterus and mean intraoperative blood loss were not statistically different. When we compared the outcomes for 20 cases in each group, using the same energy sealing device in a short period of time, only mean operative time was statistically different between the 3D-TLH and 2D-TLH groups (113±19 vs. 133±21 min). During the observation period, there was one occurrence of postoperative peritonitis in the 2D-TLH group and one occurrence of vaginal cuff dehiscence in each group, which was not statistically different. The surgeon and assistant surgeons did not report any symptoms attributable to the 3D imaging system such as dizziness, eyestrain, nausea, and headache. Therefore, we conclude that the 3D laparoscopic system could be used safely and efficiently for TLH.

Pocket Guide to Transportation 2016

DOT National Transportation Integrated Search

2016-01-01

The 2016 Pocket Guide to Transportation is a compilation of statistics that provides key information on the U.S. transportation system and highlights major trends. Intended as a compact reference, it supports the Bureau of Transportation Statistics m...

Pocket Guide to Transportation 2015

DOT National Transportation Integrated Search

2015-01-01

The 2015 Pocket Guide to Transportation is a compilation of statistics that provide key information and highlight major trends on the U.S. transportation system. Intended as a compact reference, it supports the Bureau of Transportation Statistics mis...

Pocket guide to transportation, 1998

DOT National Transportation Integrated Search

1998-12-01

The statistics in this Pocket Guide to Transportation were compiled by the Bureau of Transportation Statistics from multiple sources. The guide is divided into four sections: (1) transportation system extent and use, (2) transportation and the econom...

Rear-End Crashes: Problem Size Assessment And Statistical Description

DOT National Transportation Integrated Search

1993-05-01

KEYWORDS : RESEARCH AND DEVELOPMENT OR R&D, ADVANCED VEHICLE CONTROL & SAFETY SYSTEMS OR AVCSS, INTELLIGENT VEHICLE INITIATIVE OR IVI : THIS DOCUMENT PRESENTS PROBLEM SIZE ASSESSMENTS AND STATISTICAL CRASH DESCRIPTION FOR REAR-END CRASHES, INC...

Pocket Guide to Transportation 2014

DOT National Transportation Integrated Search

2014-01-01

The 2014 Pocket Guide to Transportation is a compilation of statistics related to the performance and impact of the U.S. transportation system. Intended as a compact reference, it supports the Bureau of Transportation Statistics mission to create,...

Statistical Determination of the Gating Windows for Respiratory-Gated Radiotherapy Using a Visible Guiding System.

PubMed

Oh, Se An; Yea, Ji Woon; Kim, Sung Kyu

2016-01-01

Respiratory-gated radiation therapy (RGRT) is used to minimize the radiation dose to normal tissue in lung-cancer patients. Although determining the gating window in the respiratory phase of patients is important in RGRT, it is not easy. Our aim was to determine the optimal gating window when using a visible guiding system for RGRT. Between April and October 2014, the breathing signals of 23 lung-cancer patients were recorded with a real-time position management (RPM) respiratory gating system (Varian, USA). We performed statistical analysis with breathing signals to find the optimal gating window for guided breathing in RGRT. When we compared breathing signals before and after the breathing training, 19 of the 23 patients showed statistically significant differences (p < 0.05). The standard deviation of the respiration signals after breathing training was lowest for phases of 30%-70%. The results showed that the optimal gating window in RGRT is 40% (30%-70%) with respect to repeatability for breathing after respiration training with the visible guiding system. RGRT was performed with the RPM system to confirm the usefulness of the visible guiding system. The RPM system and our visible guiding system improve the respiratory regularity, which in turn should improve the accuracy and efficiency of RGRT.

On information, negentropy and H-theorem

NASA Astrophysics Data System (ADS)

Chakrabarti, C. G.; Sarker, N. G.

1983-09-01

The paper deals with the imprtance of the Kullback descrimination information in the statistical characterization of negentropy of non-equilibrium state and the irreversibility of a classical dynamical system. The theory based on the Kullback discrimination information as the H-function gives new insight into the interrelation between the concepts of coarse-graining and the principle of sufficiency leading to important statistical characterization of thermal equilibrium of a closed system.

Composite Material Aircraft Electromagnetic Properties and Design Guidelines

DTIC Science & Technology

1981-01-01

Diode Characteristics for IN914 Diode at 220 MHz 7-6 7.5 Characteristics of a 2N2369A Transitor With and Without RF Interference on the Collector Lead...Analylsi Miser Reiponse Model Adjacent Channel Interference Summary 7. STATISTICAL AND NUMERICAL I. PROPAGATION MODELS ANALYSIS MASTER PROPAGATION SYSTEM...Propagation System lIPS) Simsulationst Smorothe Curve Smooth Earth (SCSIS) Oemtralltzd File Statistics Analyzer (Q63) flislance Free Space Spherical Raflectiot

Statistical determination of whole-body average SARs in a 2 GHz whole-body exposure system for unrestrained pregnant and newborn rats

NASA Astrophysics Data System (ADS)

Wang, Jianqing; Wake, Kanako; Kawai, Hiroki; Watanabe, Soichi; Fujiwara, Osamu

2012-01-01

A 2 GHz whole-body exposure to rats over a multigeneration has been conducted as part of bio-effect research in Japan. In this study, the rats moved freely in the cage inside the exposure system. From observation of the activity of rats in the cage, we found that the rats do not stay in each position with uniform possibility. In order to determine the specific absorption rate (SAR) during the entire exposure period with high accuracy, we present a new approach to statistically determine the SAR level in an exposure system. First, we divided the rat cage in the exposure system into several small areas, and derived the fraction of time the rats spent in each small area based on the classification of the documentary photos of rat activity. Then, using the fraction of time spent in each small area as a weighting factor, we calculated the statistical characteristics of the whole-body average SAR for pregnant rats and young rats during the entire exposure period. As a result, this approach gave the statistical distribution as well as the corresponding mean value, median value and mode value for the whole-body SAR so that we can reasonably clarify the relationship between the exposure level and possible biological effect.

Statistics in a Trilinear Interacting Stokes-Antistokes Boson System

NASA Astrophysics Data System (ADS)

Tänzler, W.; Schütte, F.-J.

The statistics of a system of four boson modes is treated with simultaneous Stokes-Antistokes interaction taking place. The time evolution is calculated in full quantum manner but in short time approximation. Mean photon numbers and correlations of second order are calculated. Antibunching can be found in the laser mode and in the system of Stokes and Antistokes mode.Translated AbstractStatistik in einem trilinear wechselwirkenden Stokes-Antistokes-BosonensystemDie Statistik eines Systems von vier Bosonenmoden mit gleichzeitiger Stokes-Antistokes-Wechselwirkung wird bei vollquantenphysikalischer Beschreibung in Kurzzeitnäherung untersucht. Mittlere Photonenzahlen und Korrelationen zweiter Ordnung werden berechnet. Dabei wird Antibunching sowohl in der Lasermode allein als auch im System aus Stokes- und Antistokesmode gefunden.

Evaluating model accuracy for model-based reasoning

NASA Technical Reports Server (NTRS)

Chien, Steve; Roden, Joseph

1992-01-01

Described here is an approach to automatically assessing the accuracy of various components of a model. In this approach, actual data from the operation of a target system is used to drive statistical measures to evaluate the prediction accuracy of various portions of the model. We describe how these statistical measures of model accuracy can be used in model-based reasoning for monitoring and design. We then describe the application of these techniques to the monitoring and design of the water recovery system of the Environmental Control and Life Support System (ECLSS) of Space Station Freedom.

Non-Markovian generalization of the Lindblad theory of open quantum systems

NASA Astrophysics Data System (ADS)

Breuer, Heinz-Peter

2007-02-01

A systematic approach to the non-Markovian quantum dynamics of open systems is given by the projection operator techniques of nonequilibrium statistical mechanics. Combining these methods with concepts from quantum information theory and from the theory of positive maps, we derive a class of correlated projection superoperators that take into account in an efficient way statistical correlations between the open system and its environment. The result is used to develop a generalization of the Lindblad theory to the regime of highly non-Markovian quantum processes in structured environments.

Acceleration techniques for dependability simulation. M.S. Thesis

NASA Technical Reports Server (NTRS)

Barnette, James David

1995-01-01

As computer systems increase in complexity, the need to project system performance from the earliest design and development stages increases. We have to employ simulation for detailed dependability studies of large systems. However, as the complexity of the simulation model increases, the time required to obtain statistically significant results also increases. This paper discusses an approach that is application independent and can be readily applied to any process-based simulation model. Topics include background on classical discrete event simulation and techniques for random variate generation and statistics gathering to support simulation.

Quantitative knowledge acquisition for expert systems

NASA Technical Reports Server (NTRS)

Belkin, Brenda L.; Stengel, Robert F.

1991-01-01

A common problem in the design of expert systems is the definition of rules from data obtained in system operation or simulation. While it is relatively easy to collect data and to log the comments of human operators engaged in experiments, generalizing such information to a set of rules has not previously been a direct task. A statistical method is presented for generating rule bases from numerical data, motivated by an example based on aircraft navigation with multiple sensors. The specific objective is to design an expert system that selects a satisfactory suite of measurements from a dissimilar, redundant set, given an arbitrary navigation geometry and possible sensor failures. The systematic development is described of a Navigation Sensor Management (NSM) Expert System from Kalman Filter convariance data. The method invokes two statistical techniques: Analysis of Variance (ANOVA) and the ID3 Algorithm. The ANOVA technique indicates whether variations of problem parameters give statistically different covariance results, and the ID3 algorithms identifies the relationships between the problem parameters using probabilistic knowledge extracted from a simulation example set. Both are detailed.

Statistical Tests of System Linearity Based on the Method of Surrogate Data

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

Hunter, N.; Paez, T.; Red-Horse, J.

When dealing with measured data from dynamic systems we often make the tacit assumption that the data are generated by linear dynamics. While some systematic tests for linearity and determinism are available - for example the coherence fimction, the probability density fimction, and the bispectrum - fi,u-ther tests that quanti$ the existence and the degree of nonlinearity are clearly needed. In this paper we demonstrate a statistical test for the nonlinearity exhibited by a dynamic system excited by Gaussian random noise. We perform the usual division of the input and response time series data into blocks as required by themore » Welch method of spectrum estimation and search for significant relationships between a given input fkequency and response at harmonics of the selected input frequency. We argue that systematic tests based on the recently developed statistical method of surrogate data readily detect significant nonlinear relationships. The paper elucidates the method of surrogate data. Typical results are illustrated for a linear single degree-of-freedom system and for a system with polynomial stiffness nonlinearity.« less

Modelling a real-world buried valley system with vertical non-stationarity using multiple-point statistics

NASA Astrophysics Data System (ADS)

He, Xiulan; Sonnenborg, Torben O.; Jørgensen, Flemming; Jensen, Karsten H.

2017-03-01

Stationarity has traditionally been a requirement of geostatistical simulations. A common way to deal with non-stationarity is to divide the system into stationary sub-regions and subsequently merge the realizations for each region. Recently, the so-called partition approach that has the flexibility to model non-stationary systems directly was developed for multiple-point statistics simulation (MPS). The objective of this study is to apply the MPS partition method with conventional borehole logs and high-resolution airborne electromagnetic (AEM) data, for simulation of a real-world non-stationary geological system characterized by a network of connected buried valleys that incise deeply into layered Miocene sediments (case study in Denmark). The results show that, based on fragmented information of the formation boundaries, the MPS partition method is able to simulate a non-stationary system including valley structures embedded in a layered Miocene sequence in a single run. Besides, statistical information retrieved from the AEM data improved the simulation of the geology significantly, especially for the deep-seated buried valley sediments where borehole information is sparse.

Higher-Order Statistical Correlations and Mutual Information Among Particles in a Quantum Well

NASA Astrophysics Data System (ADS)

Yépez, V. S.; Sagar, R. P.; Laguna, H. G.

2017-12-01

The influence of wave function symmetry on statistical correlation is studied for the case of three non-interacting spin-free quantum particles in a unidimensional box, in position and in momentum space. Higher-order statistical correlations occurring among the three particles in this quantum system is quantified via higher-order mutual information and compared to the correlation between pairs of variables in this model, and to the correlation in the two-particle system. The results for the higher-order mutual information show that there are states where the symmetric wave functions are more correlated than the antisymmetric ones with same quantum numbers. This holds in position as well as in momentum space. This behavior is opposite to that observed for the correlation between pairs of variables in this model, and the two-particle system, where the antisymmetric wave functions are in general more correlated. These results are also consistent with those observed in a system of three uncoupled oscillators. The use of higher-order mutual information as a correlation measure, is monitored and examined by considering a superposition of states or systems with two Slater determinants.

Mathematical and Statistical Techniques for Systems Medicine: The Wnt Signaling Pathway as a Case Study.

PubMed

MacLean, Adam L; Harrington, Heather A; Stumpf, Michael P H; Byrne, Helen M

2016-01-01

The last decade has seen an explosion in models that describe phenomena in systems medicine. Such models are especially useful for studying signaling pathways, such as the Wnt pathway. In this chapter we use the Wnt pathway to showcase current mathematical and statistical techniques that enable modelers to gain insight into (models of) gene regulation and generate testable predictions. We introduce a range of modeling frameworks, but focus on ordinary differential equation (ODE) models since they remain the most widely used approach in systems biology and medicine and continue to offer great potential. We present methods for the analysis of a single model, comprising applications of standard dynamical systems approaches such as nondimensionalization, steady state, asymptotic and sensitivity analysis, and more recent statistical and algebraic approaches to compare models with data. We present parameter estimation and model comparison techniques, focusing on Bayesian analysis and coplanarity via algebraic geometry. Our intention is that this (non-exhaustive) review may serve as a useful starting point for the analysis of models in systems medicine.

Comparative evaluation of the accuracy of linear measurements between cone beam computed tomography and 3D microtomography.

PubMed

Mangione, Francesca; Meleo, Deborah; Talocco, Marco; Pecci, Raffaella; Pacifici, Luciano; Bedini, Rossella

2013-01-01

The aim of this study was to evaluate the influence of artifacts on the accuracy of linear measurements estimated with a common cone beam computed tomography (CBCT) system used in dental clinical practice, by comparing it with microCT system as standard reference. Ten bovine bone cylindrical samples containing one implant each, able to provide both points of reference and image quality degradation, have been scanned by CBCT and microCT systems. Thanks to the software of the two systems, for each cylindrical sample, two diameters taken at different levels, by using implants different points as references, have been measured. Results have been analyzed by ANOVA and a significant statistically difference has been found. Due to the obtained results, in this work it is possible to say that the measurements made with the two different instruments are still not statistically comparable, although in some samples were obtained similar performances and therefore not statistically significant. With the improvement of the hardware and software of CBCT systems, in the near future the two instruments will be able to provide similar performances.

Introduction to the topical issue: Nonadditive entropy and nonextensive statistical mechanics

NASA Astrophysics Data System (ADS)

Sugiyama, Masaru

. Dear CMT readers, it is my pleasure to introduce you to this topical issue dealing with a new research field of great interest, nonextensive statistical mechanics. This theory was initiated by Constantino Tsallis' work in 1998, as a possible generalization of Boltzmann-Gibbs thermostatistics. It is based on a nonadditive entropy, nowadays referred to as the Tsallis entropy. Nonextensive statistical mechanics is expected to be a consistent and unified theoretical framework for describing the macroscopic properties of complex systems that are anomalous in view of ordinary thermostatistics. In such systems, the long-standing problem regarding the relationship between statistical and dynamical laws becomes highlighted, since ergodicity and mixing may not be well realized in situations such as the edge of chaos. The phase space appears to self-organize in a structure that is not simply Euclidean but (multi)fractal. Due to this nontrivial structure, the concept of homogeneity of the system, which is the basic premise in ordinary thermodynamics, is violated and accordingly the additivity postulate for the thermodynamic quantities such as the internal energy and entropy may not be justified, in general. (Physically, nonadditivity is deeply relevant to nonextensivity of a system, in which the thermodynamic quantities do not scale with size in a simple way. Typical examples are systems with long-range interactions like self-gravitating systems as well as nonneutral charged ones.) A point of crucial importance here is that, phenomenologically, such an exotic phase-space structure has a fairly long lifetime. Therefore, this state, referred to as a metaequilibrium state or a nonequilibrium stationary state, appears to be described by a generalized entropic principle different from the traditional Boltzmann-Gibbs form, even though it may eventually approach the Boltzmann-Gibbs equilibrium state. The limits t-> ∞ and N-> ∞ do not commute, where t and N are time and the number of particles, respectively. The present topical issue is devoted to summarizing the current status of nonextensive statistical mechanics from various perspectives. It is my hope that this issue can inform the reader of one of the foremost research areas in thermostatistics. This issue consists of eight articles. The first one by Tsallis and Brigatti presents a general introduction and an overview of nonextensive statistical mechanics. At first glance, generalization of the ordinary Boltzmann-Gibbs-Shannon entropy might be completely arbitrary. But Abe's article explains how Tsallis' generalization of the statistical entropy can uniquely be characterized by both physical and mathematical principles. Then, the article by Pluchino, Latora, and Rapisarda presents a strong evidence that nonextensive statistical mechanics is in fact relevant to nonextensive systems with long-range interactions. The articles by Rajagopal, by Wada, and by Plastino, Miller, and Plastino are concerned with the macroscopic thermodynamic properties of nonextensive statistical mechanics. Rajagopal discusses the first and second laws of thermodynamics. Wada develops a discussion about the condition under which the nonextensive statistical-mechanical formalism is thermodynamically stable. The work of Plastino, Miller, and Plastino addresses the thermodynamic Legendre-transform structure and its robustness for generalizations of entropy. After these fundamental investigations, Sakagami and Taruya examine the theory for self-gravitating systems. Finally, Beck presents a novel idea of the so-called superstatistics, which provides nonextensive statistical mechanics with a physical interpretation based on nonequilibrium concepts including temperature fluctuations. Its applications to hydrodynamic turbulence and pattern formation in thermal convection states are also discussed. Nonextensive statistical mechanics is already a well-studied field, and a number of works are available in the literature. It is recommended that the interested reader visit the URL http: //tsallis.cat.cbpf.br/TEMUCO.pdf. There, one can find a comprehensive list of references to more than one thousand papers including important results that, due to lack of space, have not been mentioned in the present issue. Though there are so many published works, nonextensive statistical mechanics is still a developing field. This can naturally be understood, since the program that has been undertaken is an extremely ambitious one that makes a serious attempt to enlarge the horizons of the realm of statistical mechanics. The possible influence of nonextensive statistical mechanics on continuum mechanics and thermodynamics seems to be wide and deep. I will therefore be happy if this issue contributes to attracting the interest of researchers and stimulates research activities not only in the very field of nonextensive statistical mechanics but also in the field of continuum mechanics and thermodynamics in a wider context. As the editor of the present topical issue, I would like to express my sincere thanks to all those who joined up to make this issue. I cordially thank Professor S. Abe for advising me on the editorial policy. Without his help, the present topical issue would never have been brought out.

Improving esthetic results in benign parotid surgery: statistical evaluation of facelift approach, sternocleidomastoid flap, and superficial musculoaponeurotic system flap application.

PubMed

Bianchi, Bernardo; Ferri, Andrea; Ferrari, Silvano; Copelli, Chiara; Sesenna, Enrico

2011-04-01

The purpose of this article was to analyze the efficacy of facelift incision, sternocleidomastoid muscle flap, and superficial musculoaponeurotic system flap for improving the esthetic results in patients undergoing partial parotidectomy for benign parotid tumor resection. The usefulness of partial parotidectomy is discussed, and a statistical evaluation of the esthetic results was performed. From January 1, 1996, to January 1, 2007, 274 patients treated for benign parotid tumors were studied. Of these, 172 underwent partial parotidectomy. The 172 patients were divided into 4 groups: partial parotidectomy with classic or modified Blair incision without reconstruction (group 1), partial parotidectomy with facelift incision and without reconstruction (group 2), partial parotidectomy with facelift incision associated with sternocleidomastoid muscle flap (group 3), and partial parotidectomy with facelift incision associated with superficial musculoaponeurotic system flap (group 4). Patients were considered, after a follow-up of at least 18 months, for functional and esthetic evaluation. The functional outcome was assessed considering the facial nerve function, Frey syndrome, and recurrence. The esthetic evaluation was performed by inviting the patients and a blind panel of 1 surgeon and 2 secretaries of the department to give a score of 1 to 10 to assess the final cosmetic outcome. The statistical analysis was finally performed using the Mann-Whitney U test for nonparametric data to compare the different group results. P less than .05 was considered significant. No recurrence developed in any of the 4 groups or in any of the 274 patients during the follow-up period. The statistical analysis, comparing group 1 and the other groups, revealed a highly significant statistical difference (P < .0001) for all groups. Also, when group 2 was compared with groups 3 and 4, the difference was highly significantly different statistically (P = .0018 for group 3 and P = .0005 for group 4). Finally, when groups 3 and 4 were compared, the difference was not statistically significant (P = .3467). Partial parotidectomy is the real key point for improving esthetic results in benign parotid surgery. The evaluation of functional complications and the recurrence rate in this series of patients has confirmed that this technique can be safely used for parotid benign tumor resection. The use of a facelift incision alone led to a high statistically significant improvement in the esthetic outcome. When the facelift incision was used with reconstructive techniques, such as the sternocleidomastoid muscle flap or the superficial musculoaponeurotic system flap, the esthetic results improved further. Finally, no statistically significant difference resulted comparing the use of the superficial musculoaponeurotic system and the sternocleidomastoid muscle flap. Copyright © 2011 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Experimental Determination of Dynamical Lee-Yang Zeros

NASA Astrophysics Data System (ADS)

Brandner, Kay; Maisi, Ville F.; Pekola, Jukka P.; Garrahan, Juan P.; Flindt, Christian

2017-05-01

Statistical physics provides the concepts and methods to explain the phase behavior of interacting many-body systems. Investigations of Lee-Yang zeros—complex singularities of the free energy in systems of finite size—have led to a unified understanding of equilibrium phase transitions. The ideas of Lee and Yang, however, are not restricted to equilibrium phenomena. Recently, Lee-Yang zeros have been used to characterize nonequilibrium processes such as dynamical phase transitions in quantum systems after a quench or dynamic order-disorder transitions in glasses. Here, we experimentally realize a scheme for determining Lee-Yang zeros in such nonequilibrium settings. We extract the dynamical Lee-Yang zeros of a stochastic process involving Andreev tunneling between a normal-state island and two superconducting leads from measurements of the dynamical activity along a trajectory. From the short-time behavior of the Lee-Yang zeros, we predict the large-deviation statistics of the activity which is typically difficult to measure. Our method paves the way for further experiments on the statistical mechanics of many-body systems out of equilibrium.

Are well functioning civil registration and vital statistics systems associated with better health outcomes?

PubMed

Phillips, David E; AbouZahr, Carla; Lopez, Alan D; Mikkelsen, Lene; de Savigny, Don; Lozano, Rafael; Wilmoth, John; Setel, Philip W

2015-10-03

In this Series paper, we examine whether well functioning civil registration and vital statistics (CRVS) systems are associated with improved population health outcomes. We present a conceptual model connecting CRVS to wellbeing, and describe an ecological association between CRVS and health outcomes. The conceptual model posits that the legal identity that civil registration provides to individuals is key to access entitlements and services. Vital statistics produced by CRVS systems provide essential information for public health policy and prevention. These outcomes benefit individuals and societies, including improved health. We use marginal linear models and lag-lead analysis to measure ecological associations between a composite metric of CRVS performance and three health outcomes. Results are consistent with the conceptual model: improved CRVS performance coincides with improved health outcomes worldwide in a temporally consistent manner. Investment to strengthen CRVS systems is not only an important goal for individuals and societies, but also a development imperative that is good for health. Copyright © 2015 Elsevier Ltd. All rights reserved.

Comparison of the Chinese ischemic stroke subclassification and Trial of Org 10172 in acute stroke treatment systems in minor stroke.

PubMed

Tan, Sha; Zhang, Lei; Chen, Xiaoyu; Wang, Yanqiang; Lin, Yinyao; Cai, Wei; Shan, Yilong; Qiu, Wei; Hu, Xueqiang; Lu, Zhengqi

2016-09-06

The underlying causes of minor stroke are difficult to assess. Here, we evaluate the reliability of the Chinese Ischemic Stroke Subclassification (CISS) system in patients with minor stroke, and compare it to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) system. A total of 320 patients with minor stroke were retrospectively registered and categorized into different subgroups of the CISS and TOAST by two neurologists. Inter- and intra-rater agreement with the two systems were assessed with kappa statistics. The percentage of undetermined etiology (UE) cases in the CISS system was 77.3 % less than that in the TOAST system, which was statistically significant (P < 0.001). The percentage of large artery atherosclerosis (LAA) in the CISS system was 79.7 % more than that in the TOAST system, which was also statistically significant (P < 0.001). The kappa values for inter-examiner agreement were 0.898 (P = 0.031) and 0.732 (P = 0.022) for the CISS and TOAST systems, respectively. The intra-observer reliability indexes were moderate (0.569 for neurologist A, and 0.487 for neurologist B). The CISS and TOAST systems are both reliable in classifying patients with minor stroke. CISS classified more patients into known etiologic categories without sacrificing reliability.

Statistically Validated Networks in Bipartite Complex Systems

PubMed Central

Tumminello, Michele; Miccichè, Salvatore; Lillo, Fabrizio; Piilo, Jyrki; Mantegna, Rosario N.

2011-01-01

Many complex systems present an intrinsic bipartite structure where elements of one set link to elements of the second set. In these complex systems, such as the system of actors and movies, elements of one set are qualitatively different than elements of the other set. The properties of these complex systems are typically investigated by constructing and analyzing a projected network on one of the two sets (for example the actor network or the movie network). Complex systems are often very heterogeneous in the number of relationships that the elements of one set establish with the elements of the other set, and this heterogeneity makes it very difficult to discriminate links of the projected network that are just reflecting system's heterogeneity from links relevant to unveil the properties of the system. Here we introduce an unsupervised method to statistically validate each link of a projected network against a null hypothesis that takes into account system heterogeneity. We apply the method to a biological, an economic and a social complex system. The method we propose is able to detect network structures which are very informative about the organization and specialization of the investigated systems, and identifies those relationships between elements of the projected network that cannot be explained simply by system heterogeneity. We also show that our method applies to bipartite systems in which different relationships might have different qualitative nature, generating statistically validated networks in which such difference is preserved. PMID:21483858

Entropy for Mechanically Vibrating Systems

NASA Astrophysics Data System (ADS)

Tufano, Dante

The research contained within this thesis deals with the subject of entropy as defined for and applied to mechanically vibrating systems. This work begins with an overview of entropy as it is understood in the fields of classical thermodynamics, information theory, statistical mechanics, and statistical vibroacoustics. Khinchin's definition of entropy, which is the primary definition used for the work contained in this thesis, is introduced in the context of vibroacoustic systems. The main goal of this research is to to establish a mathematical framework for the application of Khinchin's entropy in the field of statistical vibroacoustics by examining the entropy context of mechanically vibrating systems. The introduction of this thesis provides an overview of statistical energy analysis (SEA), a modeling approach to vibroacoustics that motivates this work on entropy. The objective of this thesis is given, and followed by a discussion of the intellectual merit of this work as well as a literature review of relevant material. Following the introduction, an entropy analysis of systems of coupled oscillators is performed utilizing Khinchin's definition of entropy. This analysis develops upon the mathematical theory relating to mixing entropy, which is generated by the coupling of vibroacoustic systems. The mixing entropy is shown to provide insight into the qualitative behavior of such systems. Additionally, it is shown that the entropy inequality property of Khinchin's entropy can be reduced to an equality using the mixing entropy concept. This equality can be interpreted as a facet of the second law of thermodynamics for vibroacoustic systems. Following this analysis, an investigation of continuous systems is performed using Khinchin's entropy. It is shown that entropy analyses using Khinchin's entropy are valid for continuous systems that can be decomposed into a finite number of modes. The results are shown to be analogous to those obtained for simple oscillators, which demonstrates the applicability of entropy-based approaches to real-world systems. Three systems are considered to demonstrate these findings: 1) a rod end-coupled to a simple oscillator, 2) two end-coupled rods, and 3) two end-coupled beams. The aforementioned work utilizes the weak coupling assumption to determine the entropy of composite systems. Following this discussion, a direct method of finding entropy is developed which does not rely on this limiting assumption. The resulting entropy provides a useful benchmark for evaluating the accuracy of the weak coupling approach, and is validated using systems of coupled oscillators. The later chapters of this work discuss Khinchin's entropy as applied to nonlinear and nonconservative systems, respectively. The discussion of entropy for nonlinear systems is motivated by the desire to expand the applicability of SEA techniques beyond the linear regime. The discussion of nonconservative systems is also crucial, since real-world systems interact with their environment, and it is necessary to confirm the validity of an entropy approach for systems that are relevant in the context of SEA. Having developed a mathematical framework for determining entropy under a number of previously unexplored cases, the relationship between thermodynamics and statistical vibroacoustics can be better understood. Specifically, vibroacoustic temperatures can be obtained for systems that are not necessarily linear or weakly coupled. In this way, entropy provides insight into how the power flow proportionality of statistical energy analysis (SEA) can be applied to a broader class of vibroacoustic systems. As such, entropy is a useful tool for both justifying and expanding the foundational results of SEA.

Zonal flows and turbulence in fluids and plasmas

NASA Astrophysics Data System (ADS)

Parker, Jeffrey Bok-Cheung

In geophysical and plasma contexts, zonal flows are well known to arise out of turbulence. We elucidate the transition from statistically homogeneous turbulence without zonal flows to statistically inhomogeneous turbulence with steady zonal flows. Starting from the Hasegawa--Mima equation, we employ both the quasilinear approximation and a statistical average, which retains a great deal of the qualitative behavior of the full system. Within the resulting framework known as CE2, we extend recent understanding of the symmetry-breaking 'zonostrophic instability'. Zonostrophic instability can be understood in a very general way as the instability of some turbulent background spectrum to a zonally symmetric coherent mode. As a special case, the background spectrum can consist of only a single mode. We find that in this case the dispersion relation of zonostrophic instability from the CE2 formalism reduces exactly to that of the 4-mode truncation of generalized modulational instability. We then show that zonal flows constitute pattern formation amid a turbulent bath. Zonostrophic instability is an example of a Type I s instability of pattern-forming systems. The broken symmetry is statistical homogeneity. Near the bifurcation point, the slow dynamics of CE2 are governed by a well-known amplitude equation, the real Ginzburg-Landau equation. The important features of this amplitude equation, and therefore of the CE2 system, are multiple. First, the zonal flow wavelength is not unique. In an idealized, infinite system, there is a continuous band of zonal flow wavelengths that allow a nonlinear equilibrium. Second, of these wavelengths, only those within a smaller subband are stable. Unstable wavelengths must evolve to reach a stable wavelength; this process manifests as merging jets. These behaviors are shown numerically to hold in the CE2 system, and we calculate a stability diagram. The stability diagram is in agreement with direct numerical simulations of the quasilinear system. The use of statistically-averaged equations and the pattern formation methodology provide a path forward for further systematic investigations of zonal flows and their interactions with turbulence.

North American transportation : statistics on Canadian, Mexican, and United States transportation

DOT National Transportation Integrated Search

1994-05-01

North American Transportation: Statistics on Canadian, Mexican, and United States transportation contains extensive data on the size and scope, use, employment, fuel consumption, and economic role of each country's transportation system. It was publi...

Use and Characteristics of Electronic Health Record Systems among Office-Based Physician Practices: United States, ...

MedlinePlus

... on Vital and Health Statistics Annual Reports Health Survey Research Methods Conference Reports from the National Medical Care Utilization and Expenditure Survey Clearinghouse on Health Indexes Statistical Notes for Health ...

Semi-Poisson statistics in quantum chaos.

PubMed

García-García, Antonio M; Wang, Jiao

2006-03-01

We investigate the quantum properties of a nonrandom Hamiltonian with a steplike singularity. It is shown that the eigenfunctions are multifractals and, in a certain range of parameters, the level statistics is described exactly by semi-Poisson statistics (SP) typical of pseudointegrable systems. It is also shown that our results are universal, namely, they depend exclusively on the presence of the steplike singularity and are not modified by smooth perturbations of the potential or the addition of a magnetic flux. Although the quantum properties of our system are similar to those of a disordered conductor at the Anderson transition, we report important quantitative differences in both the level statistics and the multifractal dimensions controlling the transition. Finally, the study of quantum transport properties suggests that the classical singularity induces quantum anomalous diffusion. We discuss how these findings may be experimentally corroborated by using ultracold atoms techniques.

The Statistical Loop Analyzer (SLA)

NASA Technical Reports Server (NTRS)

Lindsey, W. C.

1985-01-01

The statistical loop analyzer (SLA) is designed to automatically measure the acquisition, tracking and frequency stability performance characteristics of symbol synchronizers, code synchronizers, carrier tracking loops, and coherent transponders. Automated phase lock and system level tests can also be made using the SLA. Standard baseband, carrier and spread spectrum modulation techniques can be accomodated. Through the SLA's phase error jitter and cycle slip measurements the acquisition and tracking thresholds of the unit under test are determined; any false phase and frequency lock events are statistically analyzed and reported in the SLA output in probabilistic terms. Automated signal drop out tests can be performed in order to trouble shoot algorithms and evaluate the reacquisition statistics of the unit under test. Cycle slip rates and cycle slip probabilities can be measured using the SLA. These measurements, combined with bit error probability measurements, are all that are needed to fully characterize the acquisition and tracking performance of a digital communication system.

An analysis of I/O efficient order-statistic-based techniques for noise power estimation in the HRMS sky survey's operational system

NASA Technical Reports Server (NTRS)

Zimmerman, G. A.; Olsen, E. T.

1992-01-01

Noise power estimation in the High-Resolution Microwave Survey (HRMS) sky survey element is considered as an example of a constant false alarm rate (CFAR) signal detection problem. Order-statistic-based noise power estimators for CFAR detection are considered in terms of required estimator accuracy and estimator dynamic range. By limiting the dynamic range of the value to be estimated, the performance of an order-statistic estimator can be achieved by simpler techniques requiring only a single pass of the data. Simple threshold-and-count techniques are examined, and it is shown how several parallel threshold-and-count estimation devices can be used to expand the dynamic range to meet HRMS system requirements with minimal hardware complexity. An input/output (I/O) efficient limited-precision order-statistic estimator with wide but limited dynamic range is also examined.

Application of statistical classification methods for predicting the acceptability of well-water quality

NASA Astrophysics Data System (ADS)

Cameron, Enrico; Pilla, Giorgio; Stella, Fabio A.

2018-06-01

The application of statistical classification methods is investigated—in comparison also to spatial interpolation methods—for predicting the acceptability of well-water quality in a situation where an effective quantitative model of the hydrogeological system under consideration cannot be developed. In the example area in northern Italy, in particular, the aquifer is locally affected by saline water and the concentration of chloride is the main indicator of both saltwater occurrence and groundwater quality. The goal is to predict if the chloride concentration in a water well will exceed the allowable concentration so that the water is unfit for the intended use. A statistical classification algorithm achieved the best predictive performances and the results of the study show that statistical classification methods provide further tools for dealing with groundwater quality problems concerning hydrogeological systems that are too difficult to describe analytically or to simulate effectively.

Canonical Statistical Model for Maximum Expected Immission of Wire Conductor in an Aperture Enclosure

NASA Technical Reports Server (NTRS)

Bremner, Paul G.; Vazquez, Gabriel; Christiano, Daniel J.; Trout, Dawn H.

2016-01-01

Prediction of the maximum expected electromagnetic pick-up of conductors inside a realistic shielding enclosure is an important canonical problem for system-level EMC design of space craft, launch vehicles, aircraft and automobiles. This paper introduces a simple statistical power balance model for prediction of the maximum expected current in a wire conductor inside an aperture enclosure. It calculates both the statistical mean and variance of the immission from the physical design parameters of the problem. Familiar probability density functions can then be used to predict the maximum expected immission for deign purposes. The statistical power balance model requires minimal EMC design information and solves orders of magnitude faster than existing numerical models, making it ultimately viable for scaled-up, full system-level modeling. Both experimental test results and full wave simulation results are used to validate the foundational model.

Non-Gaussian statistics of extreme events in stimulated Raman scattering: The role of coherent memory and source noise

NASA Astrophysics Data System (ADS)

Monfared, Yashar E.; Ponomarenko, Sergey A.

2017-10-01

We explore theoretically and numerically extreme event excitation in stimulated Raman scattering in gases. We consider gas-filled hollow-core photonic crystal fibers as a particular system realization. We show that moderate amplitude pump fluctuations obeying Gaussian statistics lead to the emergence of heavy-tailed non-Gaussian statistics as coherent seed Stokes pulses are amplified on propagation along the fiber. We reveal the crucial role that coherent memory effects play in causing non-Gaussian statistics of the system. We discover that extreme events can occur even at the initial stage of stimulated Raman scattering when one can neglect energy depletion of an intense, strongly fluctuating Gaussian pump source. Our analytical results in the undepleted pump approximation explicitly illustrate power-law probability density generation as the input pump noise is transferred to the output Stokes pulses.

Meteor trail footprint statistics

NASA Astrophysics Data System (ADS)

Mui, S. Y.; Ellicott, R. C.

Footprint statistics derived from field-test data are presented. The statistics are the probability that two receivers will lie in the same footprint. The dependence of the footprint statistics on the transmitter range, link orientation, and antenna polarization are examined. Empirical expressions for the footprint statistics are presented. The need to distinguish the instantaneous footprint, which is the area illuminated at a particular instant, from the composite footprint, which is the total area illuminated during the lifetime of the meteor trail, is explained. The statistics for the instantaneous and composite footprints have been found to be similar. The only significant difference lies in the parameter that represents the probability of two colocated receivers being in the same footprint. The composite footprint statistics can be used to calculate the space diversity gain of a multiple-receiver system. The instantaneous footprint statistics are useful in the evaluation of the interference probability in a network of meteor burst communication nodes.

Incorporation of operator knowledge for improved HMDS GPR classification

NASA Astrophysics Data System (ADS)

Kennedy, Levi; McClelland, Jessee R.; Walters, Joshua R.

2012-06-01

The Husky Mine Detection System (HMDS) detects and alerts operators to potential threats observed in groundpenetrating RADAR (GPR) data. In the current system architecture, the classifiers have been trained using available data from multiple training sites. Changes in target types, clutter types, and operational conditions may result in statistical differences between the training data and the testing data for the underlying features used by the classifier, potentially resulting in an increased false alarm rate or a lower probability of detection for the system. In the current mode of operation, the automated detection system alerts the human operator when a target-like object is detected. The operator then uses data visualization software, contextual information, and human intuition to decide whether the alarm presented is an actual target or a false alarm. When the statistics of the training data and the testing data are mismatched, the automated detection system can overwhelm the analyst with an excessive number of false alarms. This is evident in the performance of and the data collected from deployed systems. This work demonstrates that analyst feedback can be successfully used to re-train a classifier to account for variable testing data statistics not originally captured in the initial training data.

CDC National Health Report: leading causes of morbidity and mortality and associated behavioral risk and protective factors--United States, 2005-2013.

PubMed

Johnson, Nicole Blair; Hayes, Locola D; Brown, Kathryn; Hoo, Elizabeth C; Ethier, Kathleen A

2014-10-31

Although substantial progress has been made in improving the health of persons in the United States, serious problems remain to be solved. Life expectancy is increasing, and the rates of the leading causes of death are improving in many cases; however, numerous indicators (i.e., measures of observed or calculated data on the status of a condition) of the health and safety of the U.S. population remain poor. This report reviews population health in the United States and provides an assessment of recent progress in meeting high-priority health objectives. The health status indicators described in this report were selected because of their direct relation to the leading causes of death and other substantial sources of morbidity and mortality and should be the focus of prevention efforts. Data are reported starting in 2005 (or the earliest available year since 2005) through the current data year. Because data sources and specific indicators vary regarding when data are available, the most recent year for which data are available might range from 2010 to 2013. Data were obtained from 17 CDC surveys or surveillance systems and three non-CDC sources to provide a view of this particular point of time in the nation's health and trends in recent years. Data from the following CDC surveillance systems and surveys were used: Behavioral Risk Factor Surveillance System (BRFSS); Emerging Infections Program/Active Bacterial Core surveillance (EIP/ABCs); Foodborne Diseases Active Surveillance Network (FoodNet); Internet Panel Surveys: Influenza Vaccination Coverage Among Health-Care Personnel and Influenza Vaccination Coverage Among Pregnant Women; National Ambulatory Medical Care Survey (NAMCS); National Health and Nutrition Examination Survey (NHANES); National Health Interview Survey (NHIS); National Healthcare Safety Network (NHSN); National HIV Surveillance System; National Hospital Discharge Survey (NHDS); National Immunization Survey (NIS); National Immunization Survey-Teen (NIS-Teen); National Notifiable Disease Surveillance System (NNDSS); Nationally Notifiable STD Surveillance; National Vital Statistics System (NVSS); and Youth Risk Behavior Surveillance System (YRBSS). Three non-CDC sources were used: the Alcohol and Tobacco Tax and Trade Bureau Monthly Statistical Releases; the National Highway Traffic Safety Administration Fatality Analysis Reporting System (FARS); and the Substance Abuse and Mental Health Services Administration's National Survey on Drug Use and Health (NSDUH). Since 2005, life expectancy at birth in the U.S. has increased by 1 year; however, the number of persons who died prematurely was relatively constant. The years of potential life lost declined for eight of the 10 leading causes of death. Age-adjusted rates declined among all leading causes except deaths attributable to Alzheimer's disease and suicide, although the numbers of deaths increased for most causes. Heart disease, stroke, and deaths attributed to motor-vehicle injuries demonstrated notable declines since 2005. Numbers and rates increased for both Alzheimer's disease and suicide. The number of deaths from drug poisoning increased by approximately 11,000, and the number of deaths among older adults caused by falls increased by approximately 7,000. Risk and protective factors for these leading causes of death also showed mixed progress. Current smoking among adults remained stable at approximately 25% while smoking among youths declined to a record low of 15.7%. Obesity rates remained level at approximately 35% for adults and approximately 17% for youths. Approximately 21% of adults met recommended levels of physical activity, consistent with results recorded in the 3 previous years. Control of blood pressure and cholesterol increased to 46.3% and 29.5%, respectively. During the 2012-13 influenza season, vaccination rates reached highs of 72.0% for health-care personnel, 56.6% for children aged <17 years, 50.5% for pregnant women, and 41.5% for persons aged >18 years. Other important measures of the health of the U.S. population also varied. Rates of foodborne illness varied from year to year, with average annual increases for Salmonella and Salmonella serotype Enteritidis. Listeria rates were stable in recent years at 0.26 cases per 100,000 population. Shiga toxin-producing E. coli (STEC) O157 increased during the past 3 years to a rate of 1.15 cases per 100,000 population, even though the annual change for the study period noted an average decline overall. Health-care-associated infections declined, on average, for central-line associated bloodstream infections (CLABSI), surgical site infections (SSI), and Methicillin-resistant Staphylococcus aureus (MRSA) infection. The percentage of persons living with HIV who know their serostatus increased to 84.2%, but trends fluctuated for the number of new HIV infections and the rate of HIV transmission among adolescents and adults. Chlamydia rates increased by an average of 3.3% per year for persons aged 15-19 years and by 4.9% per year for women aged 20-24 years. The number of new cases of hepatitis C and hepatitis C-associated deaths increased by an average of 6.4% and 6.0% per year. Indictors of maternal and child health all improved, including historically low rates of infant mortality (6.1 per 1,000 live births) and teen births (26.6 per 1,000 female population). The percentage of infants breastfed at 6 months increased to 49.4%. Among children aged 19-35 months, 70.4% received the set of universally recommended vaccines, an increase of 2.9% from the previous year. The findings in this report indicate that progress has been steady but slow for many of the priority health issues in the United States. The age-adjusted rates for most of the leading causes of death are declining, but in some cases, the number of deaths is increasing, in part reflecting the growing U.S. population. Several protective factors that have registered substantial average increases (e.g., physical activity among adults, high blood pressure control, and human papillomavirus vaccination among adolescent females) have stalled in recent years. Many protective factors, even those with impressive relative gains, still represent only a minority of the U.S. population (e.g., control of high cholesterol at 29.5%). More data are needed to properly interpret fluctuating trends, such as those observed with the number of HIV infections and HIV transmission rates. Finally, some indicators of disease that appear to be increasing, such as chlamydia and hepatitis C, reflect increased efforts to engage in targeted screening but also suggest that the actual burden of infection is much greater than the reported data alone indicate. Although not all-inclusive, this compilation highlights important health concerns, points to areas in which important success has been achieved, and highlights areas in which more effort is needed. By tracking progress, public health officials, program managers, and decision makers can better identify areas for improvement and institute policies and programs to improve health and the quality of life.

A Guide to Disability Statistics from the Behavioral Risk Factors Surveillance System. Disability Statistics User Guide Series

ERIC Educational Resources Information Center

Erickson, William A.; Dumoulin-Smith, Adrien

2009-01-01

The mission of the Cornell StatsRRTC is to bridge the divide between the sources of disability data and the users of disability statistics. One product of this effort is a set of "User Guides" to national survey data that collect information on the disability population. The purpose of each of the "User Guides" is to provide…

The Evolution of Random Number Generation in MUVES

DTIC Science & Technology

2017-01-01

mathematical basis and statistical justification for algorithms used in the code. The working code provided produces results identical to the current...MUVES, includ- ing the mathematical basis and statistical justification for algorithms used in the code. The working code provided produces results...questionable numerical and statistical properties. The development of the modern system is traced through software change requests, resulting in a random number

Nowcasting Cloud Fields for U.S. Air Force Special Operations

DTIC Science & Technology

2017-03-01

application of Bayes’ Rule offers many advantages over Kernel Density Estimation (KDE) and other commonly used statistical post-processing methods...reflectance and probability of cloud. A statistical post-processing technique is applied using Bayesian estimation to train the system from a set of past...nowcasting, low cloud forecasting, cloud reflectance, ISR, Bayesian estimation, statistical post-processing, machine learning 15. NUMBER OF PAGES

Aero-Optics Measurement System for the AEDC Aero-Optics Test Facility

DTIC Science & Technology

1991-02-01

Pulse Energy Statistics , 150 Pulses ........................................ 41 AEDC-TR-90-20 APPENDIXES A. Optical Performance of Heated Windows...hypersonic wind tunnel, where the requisite extensive statistical database can be developed in a cost- and time-effective manner. Ground testing...At the present time at AEDC, measured AO parameter statistics are derived from sets of image-spot recordings with a set containing as many as 150

Data Comparability and Public Policy: New Interest in Public Library Data. Papers Presented at Meetings of the American Statistical Association. Working Paper Series.

ERIC Educational Resources Information Center

National Center for Education Statistics (ED), Washington, DC.

The four papers contained in this volume were presented at the August 1994 meetings of the American Statistical Association as a session titled, "Public Policy and Data Comparability: New Interest in Public Library Data." The first paper, "Public Library Statistics: Two Systems Compared" (Mary Jo Lynch), describes two systems…

The Shock and Vibration Digest. Volume 16, Number 3

DTIC Science & Technology

1984-03-01

Fluid-induced Statistical Energy Analysis Method excitation, Wind tunnel testing V.R. Miller and L.L. Faulkner Flight Dynamics Lab., Air Force...84475 wall by the statistical energy analysis (SEA) method. The fuselage structure is represented as a series of curved, iso- Probabilistic Fracture...heavy are demonstrated in three-dimensional form. floor, a statistical energy analysis (SEA) model is presented. Only structural systems (i.e., no

The Warning System in Disaster Situations: A Selective Analysis.

DTIC Science & Technology

DISASTERS, *WARNING SYSTEMS), CIVIL DEFENSE, SOCIAL PSYCHOLOGY, REACTION(PSYCHOLOGY), FACTOR ANALYSIS, CLASSIFICATION, STATISTICAL DATA, TIME ... MANAGEMENT PLANNING AND CONTROL, DAMAGE, CONTROL SYSTEMS, THREAT EVALUATION, DECISION MAKING, DATA PROCESSING, COMMUNICATION SYSTEMS, NUCLEAR EXPLOSIONS

System and method for statistically monitoring and analyzing sensed conditions

DOEpatents

Pebay, Philippe P [Livermore, CA; Brandt, James M [Dublin, CA; Gentile, Ann C [Dublin, CA; Marzouk, Youssef M [Oakland, CA; Hale, Darrian J [San Jose, CA; Thompson, David C [Livermore, CA

2011-01-04

A system and method of monitoring and analyzing a plurality of attributes for an alarm condition is disclosed. The attributes are processed and/or unprocessed values of sensed conditions of a collection of a statistically significant number of statistically similar components subjected to varying environmental conditions. The attribute values are used to compute the normal behaviors of some of the attributes and also used to infer parameters of a set of models. Relative probabilities of some attribute values are then computed and used along with the set of models to determine whether an alarm condition is met. The alarm conditions are used to prevent or reduce the impact of impending failure.

System and method for statistically monitoring and analyzing sensed conditions

DOEpatents

Pebay, Philippe P [Livermore, CA; Brandt, James M [Dublin, CA; Gentile, Ann C [Dublin, CA; Marzouk, Youssef M [Oakland, CA; Hale, Darrian J [San Jose, CA; Thompson, David C [Livermore, CA

2011-01-25

A system and method of monitoring and analyzing a plurality of attributes for an alarm condition is disclosed. The attributes are processed and/or unprocessed values of sensed conditions of a collection of a statistically significant number of statistically similar components subjected to varying environmental conditions. The attribute values are used to compute the normal behaviors of some of the attributes and also used to infer parameters of a set of models. Relative probabilities of some attribute values are then computed and used along with the set of models to determine whether an alarm condition is met. The alarm conditions are used to prevent or reduce the impact of impending failure.

System and method for statistically monitoring and analyzing sensed conditions

DOEpatents

Pebay, Philippe P [Livermore, CA; Brandt, James M. , Gentile; Ann C. , Marzouk; Youssef M. , Hale; Darrian J. , Thompson; David, C [Livermore, CA

2010-07-13

A system and method of monitoring and analyzing a plurality of attributes for an alarm condition is disclosed. The attributes are processed and/or unprocessed values of sensed conditions of a collection of a statistically significant number of statistically similar components subjected to varying environmental conditions. The attribute values are used to compute the normal behaviors of some of the attributes and also used to infer parameters of a set of models. Relative probabilities of some attribute values are then computed and used along with the set of models to determine whether an alarm condition is met. The alarm conditions are used to prevent or reduce the impact of impending failure.

Computer program for prediction of fuel consumption statistical data for an upper stage three-axes stabilized on-off control system

NASA Technical Reports Server (NTRS)

1982-01-01

A FORTRAN coded computer program and method to predict the reaction control fuel consumption statistics for a three axis stabilized rocket vehicle upper stage is described. A Monte Carlo approach is used which is more efficient by using closed form estimates of impulses. The effects of rocket motor thrust misalignment, static unbalance, aerodynamic disturbances, and deviations in trajectory, mass properties and control system characteristics are included. This routine can be applied to many types of on-off reaction controlled vehicles. The pseudorandom number generation and statistical analyses subroutines including the output histograms can be used for other Monte Carlo analyses problems.

Energy-density field approach for low- and medium-frequency vibroacoustic analysis of complex structures using a statistical computational model

NASA Astrophysics Data System (ADS)

Kassem, M.; Soize, C.; Gagliardini, L.

2009-06-01

In this paper, an energy-density field approach applied to the vibroacoustic analysis of complex industrial structures in the low- and medium-frequency ranges is presented. This approach uses a statistical computational model. The analyzed system consists of an automotive vehicle structure coupled with its internal acoustic cavity. The objective of this paper is to make use of the statistical properties of the frequency response functions of the vibroacoustic system observed from previous experimental and numerical work. The frequency response functions are expressed in terms of a dimensionless matrix which is estimated using the proposed energy approach. Using this dimensionless matrix, a simplified vibroacoustic model is proposed.

Statistical assessment of speech system performance

NASA Technical Reports Server (NTRS)

Moshier, Stephen L.

1977-01-01

Methods for the normalization of performance tests results of speech recognition systems are presented. Technological accomplishments in speech recognition systems, as well as planned research activities are described.

Scan statistics with local vote for target detection in distributed system

NASA Astrophysics Data System (ADS)

Luo, Junhai; Wu, Qi

2017-12-01

Target detection has occupied a pivotal position in distributed system. Scan statistics, as one of the most efficient detection methods, has been applied to a variety of anomaly detection problems and significantly improves the probability of detection. However, scan statistics cannot achieve the expected performance when the noise intensity is strong, or the signal emitted by the target is weak. The local vote algorithm can also achieve higher target detection rate. After the local vote, the counting rule is always adopted for decision fusion. The counting rule does not use the information about the contiguity of sensors but takes all sensors' data into consideration, which makes the result undesirable. In this paper, we propose a scan statistics with local vote (SSLV) method. This method combines scan statistics with local vote decision. Before scan statistics, each sensor executes local vote decision according to the data of its neighbors and its own. By combining the advantages of both, our method can obtain higher detection rate in low signal-to-noise ratio environment than the scan statistics. After the local vote decision, the distribution of sensors which have detected the target becomes more intensive. To make full use of local vote decision, we introduce a variable-step-parameter for the SSLV. It significantly shortens the scan period especially when the target is absent. Analysis and simulations are presented to demonstrate the performance of our method.

Assessment of the long-lead probabilistic prediction for the Asian summer monsoon precipitation (1983-2011) based on the APCC multimodel system and a statistical model

NASA Astrophysics Data System (ADS)

Sohn, Soo-Jin; Min, Young-Mi; Lee, June-Yi; Tam, Chi-Yung; Kang, In-Sik; Wang, Bin; Ahn, Joong-Bae; Yamagata, Toshio

2012-02-01

The performance of the probabilistic multimodel prediction (PMMP) system of the APEC Climate Center (APCC) in predicting the Asian summer monsoon (ASM) precipitation at a four-month lead (with February initial condition) was compared with that of a statistical model using hindcast data for 1983-2005 and real-time forecasts for 2006-2011. Particular attention was paid to probabilistic precipitation forecasts for the boreal summer after the mature phase of El Niño and Southern Oscillation (ENSO). Taking into account the fact that coupled models' skill for boreal spring and summer precipitation mainly comes from their ability to capture ENSO teleconnection, we developed the statistical model using linear regression with the preceding winter ENSO condition as the predictor. Our results reveal several advantages and disadvantages in both forecast systems. First, the PMMP appears to have higher skills for both above- and below-normal categories in the six-year real-time forecast period, whereas the cross-validated statistical model has higher skills during the 23-year hindcast period. This implies that the cross-validated statistical skill may be overestimated. Second, the PMMP is the better tool for capturing atypical ENSO (or non-canonical ENSO related) teleconnection, which has affected the ASM precipitation during the early 1990s and in the recent decade. Third, the statistical model is more sensitive to the ENSO phase and has an advantage in predicting the ASM precipitation after the mature phase of La Niña.

Toward Global Comparability of Sexual Orientation Data in Official Statistics: A Conceptual Framework of Sexual Orientation for Health Data Collection in New Zealand's Official Statistics System

PubMed Central

Gray, Alistair; Veale, Jaimie F.; Binson, Diane; Sell, Randell L.

2013-01-01

Objective. Effectively addressing health disparities experienced by sexual minority populations requires high-quality official data on sexual orientation. We developed a conceptual framework of sexual orientation to improve the quality of sexual orientation data in New Zealand's Official Statistics System. Methods. We reviewed conceptual and methodological literature, culminating in a draft framework. To improve the framework, we held focus groups and key-informant interviews with sexual minority stakeholders and producers and consumers of official statistics. An advisory board of experts provided additional guidance. Results. The framework proposes working definitions of the sexual orientation topic and measurement concepts, describes dimensions of the measurement concepts, discusses variables framing the measurement concepts, and outlines conceptual grey areas. Conclusion. The framework proposes standard definitions and concepts for the collection of official sexual orientation data in New Zealand. It presents a model for producers of official statistics in other countries, who wish to improve the quality of health data on their citizens. PMID:23840231

Extreme event statistics in a drifting Markov chain

NASA Astrophysics Data System (ADS)

Kindermann, Farina; Hohmann, Michael; Lausch, Tobias; Mayer, Daniel; Schmidt, Felix; Widera, Artur

2017-07-01

We analyze extreme event statistics of experimentally realized Markov chains with various drifts. Our Markov chains are individual trajectories of a single atom diffusing in a one-dimensional periodic potential. Based on more than 500 individual atomic traces we verify the applicability of the Sparre Andersen theorem to our system despite the presence of a drift. We present detailed analysis of four different rare-event statistics for our system: the distributions of extreme values, of record values, of extreme value occurrence in the chain, and of the number of records in the chain. We observe that, for our data, the shape of the extreme event distributions is dominated by the underlying exponential distance distribution extracted from the atomic traces. Furthermore, we find that even small drifts influence the statistics of extreme events and record values, which is supported by numerical simulations, and we identify cases in which the drift can be determined without information about the underlying random variable distributions. Our results facilitate the use of extreme event statistics as a signal for small drifts in correlated trajectories.

Universal statistics of vortex tangles in three-dimensional random waves

NASA Astrophysics Data System (ADS)

Taylor, Alexander J.

2018-02-01

The tangled nodal lines (wave vortices) in random, three-dimensional wavefields are studied as an exemplar of a fractal loop soup. Their statistics are a three-dimensional counterpart to the characteristic random behaviour of nodal domains in quantum chaos, but in three dimensions the filaments can wind around one another to give distinctly different large scale behaviours. By tracing numerically the structure of the vortices, their conformations are shown to follow recent analytical predictions for random vortex tangles with periodic boundaries, where the local disorder of the model ‘averages out’ to produce large scale power law scaling relations whose universality classes do not depend on the local physics. These results explain previous numerical measurements in terms of an explicit effect of the periodic boundaries, where the statistics of the vortices are strongly affected by the large scale connectedness of the system even at arbitrarily high energies. The statistics are investigated primarily for static (monochromatic) wavefields, but the analytical results are further shown to directly describe the reconnection statistics of vortices evolving in certain dynamic systems, or occurring during random perturbations of the static configuration.

Are there pollination syndromes in the Australian epacrids (Ericaceae: Styphelioideae)? A novel statistical method to identify key floral traits per syndrome

PubMed Central

Johnson, Karen A.

2013-01-01

Background and Aims Convergent floral traits hypothesized as attracting particular pollinators are known as pollination syndromes. Floral diversity suggests that the Australian epacrid flora may be adapted to pollinator type. Currently there are empirical data on the pollination systems for 87 species (approx. 15 % of Australian epacrids). This provides an opportunity to test for pollination syndromes and their important morphological traits in an iconic element of the Australian flora. Methods Data on epacrid–pollinator relationships were obtained from published literature and field observation. A multivariate approach was used to test whether epacrid floral attributes related to pollinator profiles. Statistical classification was then used to rank floral attributes according to their predictive value. Data sets excluding mixed pollination systems were used to test the predictive power of statistical classification to identify pollination models. Key Results Floral attributes are correlated with bird, fly and bee pollination. Using floral attributes identified as correlating with pollinator type, bird pollination is classified with 86 % accuracy, red flowers being the most important predictor. Fly and bee pollination are classified with 78 and 69 % accuracy, but have a lack of individually important floral predictors. Excluding mixed pollination systems improved the accuracy of the prediction of both bee and fly pollination systems. Conclusions Although most epacrids have generalized pollination systems, a correlation between bird pollination and red, long-tubed epacrids is found. Statistical classification highlights the relative importance of each floral attribute in relation to pollinator type and proves useful in classifying epacrids to bird, fly and bee pollination systems. PMID:23681546