6,745 research outputs found
Fear of the dark in children: is stationary night blindness the cause?
No abstract available
The enhanced Software Life Cyle Support Environment (ProSLCSE): Automation for enterprise and process modeling
In this paper, we have introduced a comprehensive method for enterprise modeling that addresses the three important aspects of how an organization goes about its business. FirstEP includes infrastructure modeling, information modeling, and process modeling notations that are intended to be easy to learn and use. The notations stress the use of straightforward visual languages that are intuitive, syntactically simple, and semantically rich. ProSLCSE will be developed with automated tools and services to facilitate enterprise modeling and process enactment. In the spirit of FirstEP, ProSLCSE tools will also be seductively easy to use. Achieving fully managed, optimized software development and support processes will be long and arduous for most software organizations, and many serious problems will have to be solved along the way. ProSLCSE will provide the ability to document, communicate, and modify existing processes, which is the necessary first step
Studies into the ecological energetics of the wireworm melanotus rufipes hbst. (goleoptera : elateridae)
The study was an investigation into the ecological energetics of the Elaterid, Melanotus rufipes Hbst. Prior to this study little was known of the biology and ecology of this animal, therefore such data were presented as background material for the bioenergetic study. Analyses of the head-width frequency distribution in relation to instar number revealed that male animals pass through fourteen instars and female animals through fifteen instars. The duration of the life cycle was found to be seven years in male and eight years in female animals, the adult stage lasting only one year. The population ecology of M. rufipes was investigated using random and "whole log" sampling techniques. The data were expressed as the annual change in numbers and biomass. To determine energy flow through a population of M. rufipes it was necessary to solve the bioenergetlc equations:- C = A + F 1. A = R + Pg + Pr + U 2. C = energy consumed A = energy assimilated F = energy egested R = energy respired Pg = energy of growth Pr = energy of reproduction U = energy of excretion (not measured) Preliminary feeding studies utilising simple food preference tests and flame photometry techniques revealed that M. rufipes larvae have a carnivorous preference. Further feeding studies culminated in the calculation of ingestion, assimilation and faeces production rates. No evidence could be found for feeding in the adult stage. A continuously recording electrolytic respirometer and Varburg apparatus were used to measure respiratory rates. This enabled the annual respiratory metabolism of larval and adult animals, to be calculated. Monthly values of oxygen consumption per unit weight of animal produced characteristic L-shaped curves. Data were presented on the respiratory loss of each instar per unit time. Further respiratory investigations were made into the effect of size upon metabolism, the effect of feeding on the respiratory rate and the release of CO(_2) from the spiracies of H. rufipes. Additional data suggested that temperature acclimatization is not manifest as a change in respiratory rate. Growth rates were calculated from laboratory and field data and expressed in the form of a growth curve. The calorific values of whole animals, eggs, faeces and food were determined using a Phillipson microbomb calorimeter. This enabled calorific equivalents to be calculated for all parameters of the bioenergetic equations and individual energy budgets were thus prescribed for each instar and the adult stage of M. rufipes. From these data a mean energy budget ("best estimate") was calculated thus: Mean ingestion (C):-19»55 k. cals/l00 L. timber/year, assimilation (A):- 17.48 k. cals/l00 L. timber/year, egestion (F):- 1.86 k. cals/l00 L. timber/year respiration (R):- 2.74 k. cals/l00 L.timber/year and growth (Pg):-4.15 k. cals/100 L. timber/year. The assimilation percentage on a calorific basis was 90.3% (cf. 86.3% by weight). The ratio of secondary production/respiration was 28.6%
Space shuttle external tank performance improvements: The challenge
The external tank (ET) has been actively involved in performance improvements since the inception of the space shuttle program, primarily by weight savings. Weight savings were realized on the first block of flight articles (standard weight tank). With a need for further performance improvements, the ET Program Office was requested to develop a program to reduce tank weight an additional 6000 lb and schedule delivery of the first lightweight ET (LWT) for June 1982. The weight savings program was accomplished by: (1) a unique approach to use of factors of safety; (2) design optimization; and (3) redesign of structures with large margins of safety which resulted in an actual weight savings of 7294 lb. Additional studies have identified further weight savings which are to be implemented at appropriate times in production flow. Examples are an improved thermal protection system for the LH2 tank aft dome and reduction of slosh baffles in the LO2 tank based on flight data. All performance improvements were compared and selected based on non-recurring and recurring cost and technical risk
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Sources and Ages of Ground Water in Unconfined and Confined Aquifers Beneath the U.S. High Plains
Groundwater is a valuable resource in unconfined and confined aquifers beneath the U.S. High Plains, but little is known about its age or hydrologic history. Thirty-two samples of groundwater were collected for measurement of δD, δ18O, δ13C, 14C, 3H, and 36Cl/Cl and ionic constituents from the unconfined High Plains aquifer in the Ogallala Formation and from confined aquifers in various hydrostratigraphic units beneath the southern, central, and northern High Plains. All samples of unconfined and confined groundwaters plot along the meteoric water line. δD and δ18O from the unconfined aquifer are consistent with the Modern distribution of meteoric water across North America. δD and δ18O from the confined aquifer likewise vary from south to north across the High Plains, but beneath the southern and central High Plains mean compositions are lighter in the confined aquifer than in the unconfined aquifer. Beneath the northern High Plains, δD and δ18O are the same or heavier in the confined aquifer than in the overlying unconfined aquifer. In combination, these trends show that the north-to-south range in stable isotopic compositions within the various confined aquifers is smaller than observed in the unconfined aquifer. Although age dates are uncertain, preliminary calculations suggest that unconfined groundwaters are probably less than 1,000 years old and locally as young as 25 years. Ages of groundwaters in the confined aquifers are between 20 and 32 thousand years and similar in the different study areas. Age of groundwater appears to increase along the inferred intrastratal flow path in the confined aquifers but is determined by leakage rate as well as lateral velocity. The range in isotopic composition in confined aquifers supports earlier findings that seawater temperature and patterns of atmospheric circulation during the Late Pleistocene were different from conditions affecting Modern recharge across the High Plains.Bureau of Economic Geolog
Major and minor life events as predictors of medical utilization
Research suggests stressful life events can negatively influence physical and mental health in a number of ways. While previous research indicates both major and minor life events contribute unique variance to the prediction of physical and mental symptoms, little research has examined the relationships of both major and minor life events with medical utilization. The current study included a predominantly African American, low-income sample of adults (N = 207) attending two primary care outpatient clinics and assessed their experience of both major and minor life events over the course of one year. Medical utilization data were collected over a subsequent four-year period and included total utilization, outpatient visits, emergency department visits, and hospitalizations. Hierarchical multiple regressions were used to determine if the frequency and perceived impact of major and minor stressful events predicted subsequent medical utilization in this sample of primary care patients. After controlling for age, gender, ethnicity, and number of chronic illnesses, none of the stress measures showed a significant relationship to any type of utilization in the sample as a whole. When examining only patients from the family practice clinic who had access to a regular primary care physician (N = 141), the perceived impact of minor life events made unique contributions in predicting total medical utilization and outpatient visits, such that higher perceived impact was associated with higher rates of medical services use. The frequency of minor life events was also a significant predictor of outpatient visits, with more frequent minor life events associated with greater utilization. Neither the frequency nor impact of major life events was predictive of utilization. Results indicate minor life events may influence medical utilization for some patients, although access to medical care appears to be an important variable affecting this relationship
Scanning laser source and scanning laser detection techniques for different surface crack geometries
Standard test samples typically contain simulated defects such as slots machined normal to the surface. However, real defects will not always propagate in this manner; for example, rolling contact fatigue on rails propagates at around 25º to the surface, and corrosion cracking can grow in a branched manner. Therefore, there is a need to understand how ultrasonic surface waves interact with different crack geometries. We present measurements of machined slots inclined at an angle to the surface normal, or with simple branched geometries, using laser ultrasound. Recently, Rayleigh wave enhancements observed when using the scanning laser source technique, where a generation laser is scanned along a sample, have been highlighted for their potential in detecting surface cracks. We show that the enhancement measured with laser detector scanning can give a more significant enhancement when different crack geometries are considered. We discuss the behaviour of an incident Rayleigh wave in the region of an angled defect, and consider mode-conversions which lead to a very large enhancement when the detector is close to the opening of a shallow defect. This process could be used in characterising defects, as well as being an excellent fingerprint of their presence
Farce/Farts: Divergent Styles Of Comedy In Medieval France
Wyrzucenie Uczty głupców z kościoła jest zwykle uznawane za moment narodzenia się farsy w średniowiecznej Francji. Uczta zapoczątkowała rozwój dwu nurtów nowej tradycji komediowej. W jej wystawieniach odgrywano odwrócenie ustalonego porządku społecznego oraz porządku kościelnego.Pierwszy nurt - farsowy - został podchwycony przez grupę aktorów, określających się jako współbracia głupców {confraternités des sots'). Przedstawienia bazują zwykle na dialogu. Ich tematyka dotyczy obyczajów, a farsowymi bohaterami są próżniaccy mężowie, gderające żony, kler albo lokalni urzędnicy. Stopniowo farsa staje się gatunkiem coraz bardziej wyrafinowanym. Kładziono większy nacisk na rozwój akcji oraz przedstawianych postaci. Za szczytową postać średniowiecznej farsy należy uznać osiągnięcia Pierra Pathelina. Jest to zarazem początek nowego francuskiego gatunku - komedie, poprzedzającej o dwa wieki Moliera.Drugi nurt wywodzący się z Uczty głupców jest charakterystyczny raczej dla karnawału niż dla scenicznej farsy. Większą rolę odgrywają w nim czyny niż słowa. W odwracaniu ustalonego porządku wykorzystuje się przebieranki i grube żarty, co odzwierciedla potrzebę uwolnienia się od opresywnego porządku społeczno-religijnego. Ta tradycja utrzymała się przez wieki zarówno w karnawale (i w dworskiej tradycji), jak też na francuskiej scenie wodewilowej w przedstawieniach takich jak Le Petomane. Dzisiaj reprezentują ją występy Tokyo Shock Boys oraz demonstracje takie jak parady gejów (np. Sydney Gay and Lesbian Mardi Gras).36
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Review of Data on Hydrogeology and Related Issues in Andrews County, Texas
Technical issues for siting a low-level radioactive waste repository in Andrews County, Texas, include ensuring that a considered site satisfies the licensing requirements spelled out in state regulations (TRCR Part 45). Most of Andrews County is underlain by the High Plains aquifer, which includes the Ogallala Formation as well as older Cretaceous formations. The presence of this aquifer should be expected to pose a great deal of questions from regulators and the public for licensing a low-level radioactive waste repository. Available maps do not unambiguously identify any area of Andrews County where the High Plains aquifer is absent. Possible areas that merit further evaluation include the WCS Site near the state line with New Mexico and the south-central part of the county near the border with Ector and Winkler Counties.Bureau of Economic Geolog
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Adjustment of Parameters to Improve the Calibration of the Og-n Model of the Ogallala Aquifer, Panhandle Water Planning Area
Data for this report is available at the Texas Data Repository: https://doi.org/10.18738/T8/KCMM0AThis study involved adjusting parameters within a model of the Ogallala aquifer in the northern part of the Texas Panhandle and adjacent parts of New Mexico, Oklahoma, and Kansas. The model, known as the "Ogll-n" GAM (Groundwater Availability Model) or Panhandle Water Planning Area (PWPA) model, was developed in 2000, updated in 2001 for the Panhandle Water Planning Group, and is one of the GAM models adopted by the Texas Water Development Board (TWDB). Major adjustments included:
- Assigning elevation of the base of the Ogallala aquifer to selected model cells,
- Applying recharge rates to parts of the aquifer in the model based on soil properties, and
- Modifying parameters of the MODFLOW Drain and GHB (general head boundary) packages used to simulate the flow of groundwater at the edge of the aquifer.
The steady-state (predevelopment) model error (RMSE or root mean square error) was reduced by more than 3 feet to 32 feet, which is less than 2 percent of the change in hydraulic head in monitoring wells across the model area. The RMSE error in all counties was lowered to less than 10 percent. For example, the RMSE error for Roberts County was reduced from about 26 to 22 feet, which is less than 5 percent of the hydraulic-head change across the county. The transient model RMSE error was reduced by about 6 feet to 53 feet, which is about 2 percent of the hydraulic-head change across the model area. For instance, the transient-model RMSE for Roberts County was reduced from 51 to 45 feet, which is about 6 percent of hydraulic-head change across the county. The transient-model RMSE for 10 of the 17 counties with monitoring well data is less than 10 percent. The largest RMSE (17 percent) was for Randall County where model-edge boundary conditions highly impact simulation results.Bureau of Economic Geolog
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