Procedure for generating global atmospheric engine emissions data from future supersonic transport aircraft. The 1990 high speed civil transport studies

The input for global atmospheric chemistry models was generated for baseline High Speed Civil Transport (HSCT) configurations at Mach 1.6, 2.2, and 3.2. The input is supplied in the form of number of molecules of specific exhaust constituents injected into the atmosphere per year by latitude and by altitude (for 2-D codes). Seven exhaust constituents are currently supplied: NO, NO2, CO, CO2, H2O, SO2, and THC (Trace Hydrocarbons). An eighth input is also supplied, NO(x), the sum of NO and NO2. The number of molecules of a given constituent emitted per year is a function of the total fuel burned by a supersonic fleet and the emission index (EI) of the aircraft engine for the constituent in question. The EIs for an engine are supplied directly by the engine manufacturers. The annual fuel burn of a supersonic fleet is calculated from aircraft performance and economic criteria, both of which are strongly dependent on basic design parameters such as speed and range. The altitude and latitude distribution of the emission is determined based on 10 Intern. Air Transport Assoc. (IATA) regions chosen to define the worldwide route structure for future HSCT operations and the mission flight profiles

STARTING VALUES FOR PROC MIXED WITH REPEATED MEASURES DATA

A major advantage of PROC MIXED for repeated measures data is that one could choose from many different correlated error models. However, MIXED uses default starting values that may cause difficulty obtaining REML estimates of the covariance parameters for several of the models available. This can take the form of excessively long run times or even failure to converge. We have written a program to obtain initial covariance parameter estimates that result in greatly improved performance of the REML algorithm. We will use two covariance models frequently of interest in animal health experiments, the first-order ante-dependence model [ANTE(l)] and the Toeplitz model with heterogeneous variances [TOEPH], to illustrate the use of our procedure

AFTER FURTHER REVIEW: AN UPDATE ON MODELING AND DESIGN STRATEGIES FOR AGRICULTURAL DOSE-RESPONSE EXPERIMENTS

Research investigating dose-response relationships is common in agricultural science. This paper is an expansion on previous work by Guo, et al. (2006) motivated by plant nutrition research in horticulture. Plant response to level of nutrient applied is typically sigmoidal, i.e. no response at very low levels, observable response at mid-levels, point-of-diminishing returns and plateau at high levels. Plant scientists need accurate estimates of these response relationships for many reasons, including determining the lower threshold below which plants show deficiency symptoms and the point of diminishing returns, above which excessive doses are economically and environmentally costly. Guo et al. presented models and designs that address these requirements and a simulation study to assess and compare the small-sample behavior of these models and designs. This paper expands on that simulation study. In addition, a simulation study based procedure for exploring designs for experimental scenarios fitting this description is presented. This simulation study approach utilizes simulation based fit statistics in conjunction with various lack-of-fit plots to produce a design robust to multiple candidate models

Rodent-Agriculture Interactions in No-Tillage Crop Fields

Acreage in reduced- and no-tillage farming systems has increased markedly in recent years, a trend that is expected to continue. However, small rodent populations thrive in these fields and at times dig and consume newly planted seeds and seedlings. During 1983, no-tillage corn, wheat and grain sorghum fields in western (Red Willow Co.) and eastern (Saline and Jefferson Cos.) Nebraska were evaluated to determine the distribution and food habits of the rodent species present, the damage to crops, and the availability of alternate rodent food sources. During June (post-emergence) and August (maximum corn height), 676 rodents were captured in 11 corn fields, and during July, 105 rodents were captured in 2 wheat and 2 sorghum fields. Species captured included thirteen-lined ground squirrels (spermophilusilus tr decemlineatus), Ord\u27s kangaroo rats (Diopodomys ordii), deer mice (Peromysous m a niculatus), ndT-thern grasshopper mice (onychomys leucogaster), voles (Microtus spp.), hispid pocket mice (Pero nathus hispidus) western harvest mice (Reithrodontomys to megalotis), house mice (M= musculus and short-tailed shrews (Blarina bre i auda). Rodents were distributed throughout study fields although the sample size of several species was not great enough to determine patterns

Fox Squirrels Cause Power Outages: An Urban Wildlife Problem

In urban areas, power outages are caused each year by fox squirrels (Sciurus niger) that use electrical power equipment as travel lanes, rest sites, or for other activities. When a squirrel crosses a live bare wire on a transformer, the result is a blown fuse and electrocution of the squirrel. Power company outage reports were examined to determine when and where squirrel-caused outages occurred. Sixteen field sites in Lincoln were selected for study. Eight sites encircled transformers with ≥4 squirrel-caused outages, 1980-1985, and eight were adjacent control sites with no such outages. Squirrel behavior in relation to power equipment was observed and habitat variables were measured at all sites. Additional data on vegetation within 2 m of the power equipment were collected at 22 sites in Omaha. Eleven Omaha sites were at transformers that had ≥3 squirrel-caused outages (1985-1986) and 11 were at adjacent control sites. Results indicate that problem sites had more squirrels than control sites. Numbers of leaf nests were significantly greater in problem sites (P \u3c 0.05). In addition, squirrels were observed almost twice as many minutes in problem sites, and time-area counts indicated increased numbers of squirrels in problem sites. Mean basal area of mulberries within 2 m of all power equipment and within 2 m of the power pole was 2.5 or 15 times greater, respectively, in problem sites than in control sites. Results indicate that barriers and habitat management may be potential control techniques. Results of this study provide a greater understanding of squirrel biology in urban environments and may yield greater predictability and control of squirrel-caused power outages

A STATISTICAL ANALYSIS OF THE PERFORMANCE OF MILKING SYSTEM VACUUM REGULATORS

Milking machine vacuum regulators were tested at dairies across the United States over a period of twelve years. The drop in vacuum level with increasing air flow for each regulator tested was modeled using segmented regression. Three measures of regulator performance were considered: the slope of the line in the first phase, the variability about the first line, and the join point (after which vacuum pressure began to drop rapidly). The distribution of the join point was estimated based on an accelerated failure time model with censoring, Weibull errors, a model effect, and a linear effect of set point vacuum. For each model, the average slope of the first line, the average variability about the line of the first regime, and the estimated median cfm (cubic feet of air per minute, New Zealand standard) for a join point with set point vacuum of 13 in. Hg were standardized. These standardized values were used in a cluster analysis to identify four performance groups of regulator models

Spatial variation in western corn rootworm (Coleoptera: Chrysomelidae) susceptibility to Cry3 toxins in Nebraska

Repeated use of field corn (Zea mays L.) hybrids expressing the Cry3Bb1 and mCry3A traits in Nebraska has selected for field-evolved resistance in some western corn rootworm (WCR; Diabrotica virgifera virgifera LeConte) populations. Therefore, this study was conducted to characterize spatial variation in local WCR susceptibility to Cry3Bb1 and mCry3A traits in Keith and Buffalo counties, Nebraska, and determine the relationship between past management practices and current WCR susceptibility. Adult WCR populations were collected from sampling grids during 2015 and 2016 and single-plant larval bioassays conducted with F1 progeny documented significant variation in WCR susceptibility to Cry3Bb1 and mCry3A on different spatial scales in both sampling grids. At the local level, results revealed that neighboring cornfields may support WCR populations with very different susceptibility levels, indicating that gene flow of resistant alleles from high trait survival sites is not inundating large areas. A field history index, comprised of additive and weighted variables including past WCR management tactics and agronomic practices, was developed to quantify relative selection pressure in individual fields. The field history index-Cry3 trait survivorship relationship from year 1 data was highly predictive of year 2 Cry3 trait survivorship when year 2 field history indices were inserted into the year 1 base model. Sensitivity analyses indicated years of trait use and associated selection pressure at the local level were the key drivers of WCR susceptibility to Cry3 traits in this system. Retrospective case histories from this study will inform development of optimal resistance management programs and increase understanding of plant-insect interactions that may occur when transgenic corn is deployed in the landscape. Results from this study also support current recommendations to slow or mitigate the evolution of resistance by using a multi-tactic approach to manage WCR densities in individual fields within an integrated pest management framework

Historical tank content estimate for the southwest quadrant of the Hanford 200 west area

The Historical Tank Content Estimate for the Quadrant provides historical information on a tank-by-tank basis of the radioactive mixed wastes stored in the underground single-shell tanks for the Hanford 200 West Area. This report summarized historical information such as waste history, level history, temperature history, riser configuration, tank integrity, and inventory estimates on a tank- by-tank basis. Tank farm aerial photographs and interior tank montages are also provided for each tank. A description of the development of data for the document of the inventory estimates provided by Los Alamos National Laboratory are also given in this report

Historical tank content estimate for the northwest quadrant ofthe Hanford 200 west area

The Historical Tank Content Estimate for the Quadrant provides historical information on a tank-by-tank basis of the radioactive mixed wastes stored in the underground single-shell tanks for the Hanford 200 West Area. This report summarized historical information such as waste history, level history, temperature history, riser configuration, tank integrity, and inventory estimates on a tank-by-tank basis. Tank farm aerial photographs and interior tank montages are also provided for each tank. A description of the development of data for the document of the inventory estimates provided by Los Alamos National Labo1368ratory are also given in this report