Comment on Lockerbie, N.A.: Gen. Rel. Grav. 36, 593 (2004)

We comment on the paper “ISLAND – Inverse-Square-Law Acceleration Measurement using Inertial Drift,” by Lockerbie, N.A.: Gen. Rel. Grav. 36, 593–600 (2004).     

Comparative extreme ultraviolet emission measurements for lithium and tin laser plasmas

Detailed spectroscopic studies on extreme UV emission from laser plasmas using tin and lithium planar solid targets were completed. At 13.5 nm, the best conversion efficiency (CE) for lithium was found to be 2.2% at intensities near 7 x 10(10) W/cm(2). The highest CE measured for tin was near 5.0% at an intensity close to 1 x 10(11) W/cm(2).     

Photoelastic tests on complex intersections of reinforced thin-shell cylinders

This paper presents the three-dimensional photoelastic analyses accompanied by extensive finite-element studies of several thin-shell pressure vessels with various cylindrical intersections. The models consisted of right circular cylindrical shells with diameter-to-thickness ratios of 220, reinforced with circumferential, longitudinal and diagonal T-stiffeners. The cylindrical shells and stiffeners were intersected by various smaller cylinders producing complex intersection joints which included radial and angular fillets. Each of the models was constructed from 80 to 150 parts prepared from flat sheets, “contour-cast” shells, and milled machined parts. The model techniques as well as the machining, assembling and testing methods of the pressure vessels are presented.     

Bubble clustering and trapping in large vortices. Part 1: Triggered bubbly jets investigated by phase-averaging

The characteristics of large coherent structures in turbulent, periodically-excited, as well as naturally-developing bubbly jets are investigated, and interactions between bubbles and large-scale vortices are studied quantitatively.     

Strengthening genetic services in primary care for Asian Americans and Pacific Islanders

The Association of Asian Pacific Community Health Organizations (AAPCHO) is a national membership organization of community health centers (CHCs) that serve medically underserved Asian Americans and Pacific Islanders (AAPIs) with limited English-speaking proficiency and low income. OBJECTIVES: In 1995, AAPCHO was funded for a 3-year national genetics training project to improve genetics training among primary care providers at CHCs and strengthen linkages with tertiary genetic centers (TGCs). Three model linkages between CHCs and TGCs were documented on the coordination of genetic services for medically underserved AAPIs. METHODS: Guidelines were developed for three CHCs to document their genetic programs and linkages with TGCs. In addition, one clinic conducted a mail survey to assess understanding of prenatal genetic counseling sessions by patients that visited the clinic during the past 2 years. RESULTS: Model linkages between CHCs and TGCs to improve cultural and linguistic accessibility for patients include formal coordination between the CHCs and TGCs for the delivery of genetic services and the provision of varying levels of genetic services at the CHC. From the patient survey, there was a 59% response rate among 70 surveys mailed to former patients. The survey results showed that while a majority of patients understood and recalled key genetic concepts, one-fifth of patients experienced difficulty understanding their genetic counseling sessions. CONCLUSION: Based on model linkages between CHCs and TGCs and the patient satisfaction survey results, the following strategies are recommended to improve accessibility of genetic services for medically underserved AAPIs: (1) genetics education should be developed for all levels of health center staff; (2) counseling should be culturally sensitive and focus on key issues that must be conveyed for appropriate informed consent; (3) genetics education should employ the use of translated audiovisual aids and brochures to improve understanding; (4) genetic services should be coordinated between CHCs and TGCs to provide culturally and linguistically competent care for medically underserved AAPIs, and (5) financial mechanisms should be available to support genetic testing of patients and their families with little or no coverage for genetic services.     

Gravitational Stability of the Interface in Water Over Steam Geothermal Reservoirs

Stability of a geothermal system is considered in a case when the water layer lies over the layer of superheated vapor in a stratum having relatively low permeability. This stratum locates between two parallel high permeable layers. Under the assumption of smallness of advective energy transfer as compared with the conductive one, the stationary distribution of the characteristics in the stratum with an interface of phase transition is obtained. The interface separates the domains occupied by water and vapor. Investigation of normal stability of the interface shows, that stable configurations in the geothermal system under consideration exist within the range of permeability values bounded by k 0.6 × 10^–15 m² from above. The most unstable configurations occur to be the quiescent states when the permeability exceeds a certain threshold. A sufficiently high value of permeability, satisfying the criterion of smallness of the advective energy transfer as compared with the conductive one makes it possible to explain the existence of a wide class of stable natural geothermal reservoirs, where the vapor layer underlies the water one.     

Assessing and predicting changes in vegetation cover associated with military land use activities using field monitoring data at Fort Hood, Texas

We assessed short-term impacts of changes in military training load on vegetative cover at Fort Hood, TX. From 1989 to 1995, permanent field transects were monitored for vegetative cover and land use disturbance using standard army monitoring methods [Land Condition Trend Analysis (LCTA)]. Land use intensity (training load) was quantified and used to develop a model to predict future vegetation cover values. We found that standard Army monitoring methods detected changes in installation resources associated with changes in training load. Increased training loads were associated with increased measures of disturbance, decreased ground cover, and decreased aerial vegetative cover. We found that the spatial pattern of disturbance and vegetation cover remained relatively constant over the study period despite large variations in overall training load. Our model used the consistency in spatial cover patterns over time and the strong relationship between training load and vegetation cover to predict the impact of future training loads on vegetation.     

Stochastic vehicle mobility forecasts using the nato reference mobility model

The NATO Reference Mobility Model (NRMM) is a comprehensive means of predicting the speeds of military vehicles in on-road, off road, and gap-crossing contexts. The model has been in service for many years and helps user communities concerned with vehicle design, wargaming, and strategic planning. Recent developments in computer hardware and software are creating an opportunity for NRMM to serve a tactical role on the battlefield. Adaptation of NRMM to this role requires that its users come to grips with the collection of digital data to describe vehicle, terrain, and scenario data in a real-time environment. This paper discusses the performance of NRMM when selected inputs and algorithms contain random components. A developmental pathway is outlined that leads from current deterministic mobility forecasts to stochastic forecasts capable of suggesting the risks taken when speed predictions must be made in the presence of data and algorithm errors. Concepts that express measures of confidence for wide-area mobility forecasts when errors are known with small-area detail are described. Several numerical examples are given.