Development and flight tests of a Kalman filter for navigation during terminal area and landing operations

A Kalman filter for aircraft terminal area and landing navigation was implemented and flight tested in the NASA Ames STOLAND avionics computer onboard a Twin Otter aircraft. This system combines navaid measurements from TACAN, MODILS, air data, radar altimeter sensors along with measurements from strap-down accelerometer and attitude angle sensors. The flight test results demonstrate that the Kalman filter provides improved estimates of the aircraft position and velocity as compared with estimates from the more standard complementary filter. The onboard computer implementation requirements to achieve this improved performance are discussed

Internal and external axial corner flows

The inviscid, internal, and external axial corner flows generated by two intersecting wedges traveling supersonically are obtained by use of a second-order shock-capturing, finite-difference approach. The governing equations are solved iteratively in conical coordinates to yield the complicated wave structure of the internal corner and the simple peripheral shock of the external corner. The numerical results for the internal flows compare favorably with existing experimental data

Recreational Gun Use by California Adolescents

Most research on adolescents and firearms focus on urban populations, handguns, and homicide. The present investigation examines the prevalence and correlates of recreational gun use (RGU) - for hunting or target shooting - among 5801 community-residing 12- to 17-year old Californians. Data are from the first statewide California Health Interview Survey (CHIS), and person, design, and population weights were applied to the data. About one-fifth (22.4%) of California adolescents report that they have gone hunting or target shooting. Nearly two thirds (62.8%) have hunted with a family member, typically (67.3%) their father. Recreational gun use among adolescents appears to be linked to a few basic demographic characteristics; most notably, males had an AOR of RGU nearly five times that of females. Some of the variables associated with RGU are consistent with those for violent gun use; differences, however, suggest that separate approaches to preventing firearm-related injury may be warranted

Views of Intimate Partner Violence in Same- and Opposite-Sex Relationships

Attitudes toward same-sex intimate relationships and toward intimate partner violence (IPV) are changing. Little research, however, has examined norms about IPV in same-sex relationships. Using a fractional factorial (experimental vignette) design, we conducted random-digit-dialed interviews in four languages with 3,679 community-residing adults. Multivariate analyses of responses to 14,734 vignettes suggest that IPV against gay male, lesbian, and heterosexual women is more likely than that against heterosexual men to be considered illegal, that it should be illegal, police called, and a stay-away order issued. Regardless of gender and sexual orientation, the type of abuse and whether a weapon was displayed are the strongest predictors of respondents\u27 judgments about whether a behavior is illegal and merits a range of societal interventions

Personal Awareness of Domestic Violence: Implications for Health Care Providers

To estimate how many Californians know a victim of domestic violence, to examine their knowledge of certain characteristics of the violence, and to estimate and examine such knowledge among specific demographic groups. A total of 3713 California adults (similar numbers of whites, blacks, Hispanics, Korean Americans, Vietnamese Americans, and other Asian Americans) completed a random-digit-dial interview. Respondents were asked whether a friend, relative, or coworker had been threatened or harmed by an intimate partner. Weights were applied to the cross-sectional sample to obtain estimates for the general population. Descriptive statistics and multivariate regressions were used with the full sample

Mental Health and Firearms in Community-Based Surveys: Implications for Suicide Prevention

Suicide rates are higher among those who own a handgun and among those who live in a household with a handgun. The present investigation examined the association between gun ownership and mental health, another risk factor for suicide. Data from the General Social Survey, a series of surveys of U.S. adults, were analyzed to compare general emotional and mental health, sadness and depression, functional mental health, and mental health help seeking among gun owners, persons who do not own their own gun but reside in a household with a gun, and those who do not own a gun. After taking into account a few basic demographic characteristics associated with both variables, there appears to be no association between mental health and gun ownership. Nor is there any association between mental health and living in a household with a firearm. Findings suggest that the high risk of suicide among those who own or live in a household with a gun is not related to poor mental health. Implications for prevention are discussed