Parameter uncertainty and sensitivity in a liquid-effluent dose model

Radioactive materials which are released into streams on the Savannah River Site (SRS) eventually flow into the Savannah River. Tritium, 90 Sr, 137 Cs, and 239 Pu account for the majority of the radiation dose received by users of the Savannah River. This paper focuses on the dose uncertainties originating from variability in parameters describing the transport and uptake of these nuclides. Parameter sensitivity has also been determined for each liquid pathway exposure model. The models used here to estimate radiation dose to an exposed individual provide a range of possible dose estimates that span approximately one order of magnitude. A pathway analysis reveals that aquatic food and water consumption account for more than 95% of the total dose to an individual.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42692/1/10661_2004_Article_BF00547126.pd

Reassessing the effect of colour on attitude and behavioural intentions in promotional activities: The moderating role of mood and involvement

The present research examines the effect of background colour on attitude and behavioural intentions in various promotional activities taking into consideration the moderating role of mood and involvement. Three experiments reflecting different promotional activities (window display, consumer trade show, guerrilla marketing) were conducted for this purpose. Overall, findings indicate that cool background colours, in contrast to warm colours, induce more positive attitudes and behavioural intentions mainly in positive mood, and low involvement conditions. Implications are also discussed

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

Models and computer codes for evaluating environmental radiation doses

Prior to the issuance of construction permits or operating licenses for nuclear power reactors, the U. S. Atomic Enengy Commission is required by the National Environmental Policy Act of 1969 to prepare Detalled Environmental Impact Statements. These statements contain analyses of the balance between benefits and costs of the proposed action, including the radiological impact of operation of the facillty. Methods for computing environmental radiation doses are described. A simplified model for calculation of radiation doses from radioactive effluents was developed and programmed into a conversational language, providing the fast turnaround time required. The new model is divided into four independent parts, each written as a separate program: ARRRG: calculates individual and population doses from liquid effluents; CRITR: calculates internal radiation doses to four common classes of aquatic organisms and to onganisms which consume them; FOOD: calculates doses from consumption of food crops and animal products produced on irrigated farms; and GRONK: calculates doses from gaseous effluents, to individuals and to the total population within 50 miles. The model can be used to calculate radiation doses to the total body and selected organs of individuals and population groups, and to organisms other than man. It includes all air and liquid exposure pathways thought to be significant and for which a reasonable amount of supportlng data is available. Internal doses to man are based on a 1-year radionuclide intake, assuming no prior accumulation in the body. The radionuclide content of ingested food is assumed to be at equilibrium with the environment. This paper discusses the models in detail and describes the programs ARRRG, CRITR and GRONK; the program FOOD is still being developed and is not included in this report. (CH

Nonlinear Dynamics as a Tool in Selection of Working Conditions for Radial Ball Bearing

This paper contains elements of a comprehensive research devoted to the dynamic behavior of radial ball bearings in real working conditions. The general motivation for this topic comes from the requirements for high performance operation of bearings within complex mechanical systems, defined in many industrial branches during the last decades. The discussion of the fundamental postulates of the approach used for analyzing the vibration response of rolling ball bearings in order to select the optimal working conditions is given. The certain simplifications and reductions used for analyzing the radial ball bearings are explained. The developed procedure can be used for research of influence of different damages and variable operation conditions on the rolling bearings dynamics. The detail analyses of the dynamic behavior of rolling bearings are performed for particular types of radial ball bearings in two case studies: For the damaged outer raceway surface in accordance with real fatigue damage shapes and dimensions and, for variable working temperature. Obtained results are shown by comparative diagrams of vibration and phase plane portraits. Presented results could be a base for more widely research of nonlinear dynamics of radial ball bearings with different damages and for the application of phase plane analysis in order to choose the optimal operation conditions

Nonlinear Dynamics as a Tool in Selection of Working Conditions for Radial Ball Bearing

This paper contains elements of a comprehensive research devoted to the dynamic behavior of radial ball bearings in real working conditions. The general motivation for this topic comes from the requirements for high performance operation of bearings within complex mechanical systems, defined in many industrial branches during the last decades. The discussion of the fundamental postulates of the approach used for analyzing the vibration response of rolling ball bearings in order to select the optimal working conditions is given. The certain simplifications and reductions used for analyzing the radial ball bearings are explained. The developed procedure can be used for research of influence of different damages and variable operation conditions on the rolling bearings dynamics. The detail analyses of the dynamic behavior of rolling bearings are performed for particular types of radial ball bearings in two case studies: For the damaged outer raceway surface in accordance with real fatigue damage shapes and dimensions and, for variable working temperature. Obtained results are shown by comparative diagrams of vibration and phase plane portraits. Presented results could be a base for more widely research of nonlinear dynamics of radial ball bearings with different damages and for the application of phase plane analysis in order to choose the optimal operation conditions