bluuebunny/crossref_metadata_2025_split huggingface dataset:
International Agreements on Standards in Operational Meteorology
Authors: Zavos B 
Published: March 2009

The use and international exchange of meteorological data requires agreement on such items as (a) the timeliness, accuracy, and resolution of the observations; (b) the technical and operational aspects of meteorological telecommunications; (c) the input needs and product outputs of the data processing systems; and (d) educational and training standards.
The acceptance internationally of definitions, standards, technical requirements, and operational procedures by the meteorological services of the world is the result of innumerable meetings, negotiations, renegotiations, and compromises through both official and unofficial channels.
The focus for this activity is the World Meteorological Organization (WMO), a United Nations specialized agency, which operates through its four major meteorological and operational hydrological programs.
The World Weather Watch program provides the basic information used by the meteorological services to make weather forecasts, as well as to provide climatological and other data to their users. Standards and definitions relating to all aspects of this data must be agreed to in the four official WMO languages by the international meteorological community.
Relationship of Automated Weather Observations to Subjective Elements
Authors: Lefkowitz M , Bradley JT 
Published: March 2009

Traditionally, surface weather observations have been made by human observers. It has been their difficult task to estimate subjective elements such as sky cover (in tenths) and the heights of clouds (often to the nearest 100 ft). Automation has moved slowly to replace subjective methods in the field and, even then, usually only in special areas such as runway visual range (RVR) and runway visibility (RVV). Recent work has demonstrated that automated observations of other subjective elements are feasible and are already operational at two points in the United States.
The paper reviews the concepts of RVR and RVV, and discusses in detail new methods for the automation of cloud and visibility observations. The automated observations are compared with human products made at the same time and location. The paper points out the difficulties of assessing the success of objective techniques in comparison with subjective methods.
Dispersion from Individual Sources
Authors: Pasquill F 
Published: March 2009

A brief survey is given of the present position in the specification of atmospheric dispersion parameters for use in estimating pollutant concentration from a continuous-point release.
The theorectical indications of the distribution to be expected across a time-mean plume are reviewed, with particular reference to the existence of the Gaussian form. Observational evidence, especially on vertical distribution from a surface release, is also recalled, and the practical significance of departure from an assumed Gaussian form is noted.
The use of the Taylor statistical theory in the generalized estimation of crosswind spread in quasi-ideal boundary-layer flow is briefly summarized. Recent considerations of the behavior of the crosswind component of turbulence in the surface layer and new developments from laboratory modeling of horizontal dispersion in convective mixing are noted.
A brief survey is given of the achievements of the gradient-transfer theory and the Lagrangian similarity theory in calculating vertical spread from a surface release. New tests against previous dispersion data underline inadequacies in the present approaches in very unstable conditions. Promising developments from laboratory modeling of a convectively mixed layer and from the second-order-closure modeling of the turbulent fluctuation equations are summarized.
The assimilation of theory and experience into practical systems for the specification of σy and σz is briefly reconsidered. For σy a practical procedure, based on wind direction fluctuation data, is reaffirmed. For σz a new format, which may be envisaged for future composite curves, is suggested. Finally, the inherent limitations of practical systems for estimating concentration levels are reiterated.
Urban Modeling of Inert Substances
Authors: Hanna SR 
Published: March 2009

The physical assumptions in various models for the diffusion of inert substances in urban areas are critically reviewed. It is suggested that there are no significant differences among the predictions of the models, and that often simple integral models have more valid physical assumptions than do complex computer models. Correlations between observed and predicted concentrations of carbon monoxide (CO), sulfur dioxide, and suspended particles are typically in the range of 0.4 to 0.8. The magnitude of the prediction can be expected to be within a factor of two of the observation.
Mixing depth and pollutant concentration are not well correlated (R ≃ -0.2) because local pollutant plumes do not as a rule reach the capping inversion. Inverse wind speed and pollutant concentration are better correlated (R ≃ 0.6). A method for accounting for stability in the simple Atmospheric Turbulence and Diffusion Laboratory model is suggested, based on observations of CO emissions and concentrations and of wind speeds at numerous stations.
Applications of General Meteorological Models to Air Quality Problems
Authors: Anthes RA , Warner TT 
Published: March 2009

Some of the potential applications of general meteorological models to air quality problems of mesoscale flows are discussed. Although general models are relatively expensive, they are easily modified to treat many complicated problems that are not amenable to solution by simpler methods.
Results from two meteorological models are presented to illustrate the versatility of the models. The first is a relatively simple model of the atmospheric mixed layer. A 6-h, real-data forecast is shown. The second model is a more general three-dimensional model which is capable of treating a variety of meteorological problems. A 12-h, real-data forecast of flow and precipitation over the United States is summarized. Then the model is applied to a regional-scale simulation of light wind conditions. Finally, the model is applied to small-scale flow under stable conditions over complex terrain.
Effects of Weather Fronts on Ozone Transport
Authors: Ludwig FL , Shelar E 
Published: March 2009

The object of the research discussed in this paper has been to define special meteorological conditions that are conducive to the long-range transport of ozone and its precursors, especially in highly urbanized areas like the northeastern United States. Long-range transport is an important factor in the design of ozone control strategies.
Routinely collected air quality data, special data from the Northeast Oxidant Study, and National Weather Service data and analyses were combined to determine relationships among source areas, areas of high ozone concentration, and air movement associated with different weather systems.
In the eastern United States, the warm, southwesterly winds preceding weather fronts were found to provide favorable conditions for ozone formation and transport. The alignment of the coastal source areas is such that particularly dramatic buildups of ozone result, followed by abrupt decreases in concentration as colder, cleaner air behind a front replaces the polluted air ahead of it. Examples of several such events have been analyzed.
Although air movement associated with frontal passages is only one of the important situations causing long-range transport and ozone buildup in the Northeast, the events are sufficiently common that they must be considered in the design of control strategies. Furthermore, the fact that ozone buildups are found in conjunction with frontal passages belies the common assumption that stagnating high pressure systems are required for important violations of ozone standards in the eastern United States. The results show that extended source areas, when aligned with the air flow, may lead to significant ozone concentrations even in the decidedly unstagnant air ahead of frontal zones.
Ozone Measurements at Several Rural and Urban Sites in New York State
Authors: Coffey PE , Whitby RA , Stasiuk WN , Husain L , Mohnen VA 
Published: March 2009

Since the early 1970s, research to evaluate ozone levels in ambient air has been in progress at several rural and urban site in New York State. The sites were chosen to provide ozone data above and below the nocturnal inversion layer.
Ozone from upwind sources has been shown to significantly affect both the urban and remote rural areas. Concentration isopleths show that ozone created in the urban plume of the larger urban areas significantly affects areas downwind under the plume.
The sources of ozone in the remote rural areas are still not clear. Principal ozone sources are stratospheric ozone, photochemical production from terpenes and hydrocarbons emitted from local vegetation, and ozone transported via urban plumes. Each of these three sources can be a significant contributor.
Estimating Injury from Burning Garments and Development of Concepts for Flammability Tests
Authors: Bercaw JR , Jordan KG , Moss AZ 
Published: March 2009

Part of the flammability research at Du Pont has been concerned with understanding the way various garments ignite and transfer heat under simulated conditions of use. The objective is to develop basic principles which will aid in the definition of improved products and guide the development of more appropriate test methods. To this end, we have acquired Thermo-Man, a thermally instrumented manikin and heat sensing system which produces detailed estimates of injury from burning garments. The highly sophisticated system and procedure for injury evaluation to give accurate estimates of area burned and burn depth through the human skin is reviewed. Burn injury data are presented which predict injury potential from common apparel, including fabrics from both man-made and natural fibers. Effects of garment type on potential injury and injury-time propagation are also discussed.
Thermo-Man provides a unique basis for development of concepts for more relevant and predictive flammability tests applicable to general apparel fabrics. The essential aspects of burn injury production are fabric ignition and heat transfer. Research at the National Bureau of Standards (NBS) and Du Pont is aimed at developing a heat transfer concept for possible consideration as part of a general apparel fabric flammability test method.
The Role of Tests in Defining Fire Hazard: A Concept
Authors: Roux HJ 
Published: March 2009

Recent increased concern about life safety by various interested public agencies has led to questioning the credibility of small-scale fire tests in predicting the performance of a product or system in a real-fire situation.
It is proposed that many of these fire test methods, though, can be upgraded to fire-characteristic test methods by the application of appropriate criteria. Furthermore, the results from one or more fire-characteristic test methods, plus other parameters, could then be integrated to establish the potential for harm (PH) of a product or a system. The fire hazard of a product or system can then be established by combining the potential for harm with the degree of exposure.
One pragmatic approach to establishing the integration equation for the PH of a product or system is to start with the available fire statistics for that product or system and to prepare a scenario that describes the involvement and the effects of the subject item in a fire situation. Then an integration equation that fits this scenario can be written. This approach would identify the fire-characteristic test methods and parameters that are needed to assess the PH of that product or system. Included in this concept is the idea of using full-scale fire tests either to prove the integration equation for a given product or system or to assess directly the PH of that given product or system.
Alternatively, full-scale fire tests can be used to derive the integration equation for a given product or system when no fire statistics are available for that product or system.
Effects of Prior Stress History on Irradiation-Induced Creep
Authors: Wire GL 
Published: March 2009

The purpose of this paper is to report the results of an experimental study to determine the effects of previous irradiation history on the fast-flux neutron irradiation creep behavior of 20 percent cold-worked Type 316 stainless steel for liquid metal fast breeder reactor (LMFBR) application. Previous irradiation creep experiments have involved monitoring the irradiation creep strain of specimens held at constant stress while irradiated at approximately constant temperature and flux. Under these conditions, the irradiation creep rates have been observed to vary with neutron exposure. Application of these “creep curve” data to design and analysis of reactor core structural materials requires some knowledge of how the creep rate at a given point in time depends upon the previous stress history.
In the present experiment, in-reactor stress relaxation tests were performed on specimens which had previously been irradiated in the stress-free condition to various exposures ranging from 0 to 4 × 1022 (n)/cm2 (E &gt; 0.1 MeV) at 800 and 1000 °F (427 and 538 °C). It was found that the creep coefficients derived from this experiment were essentially the same as that obtained from the constant-load in-reactor test when allowance was made for thermal deformations. Thus it is concluded that, for the materials and conditions studied, the irradiation creep rate is essentially independent of previous stress history. This result may be rationalized if the microstructural development during irradiation is influenced predominantly by the irradiation flux and temperature variables and only to a minor extent by the irradiation creep deformation.
The sensitivity of the experimental technique to in-reactor effects coupled with supplementary thermal control studies led to a new insight into what has been called transient irradiation creep. The results of this experiment suggest that thermal effects can account for the initially higher creep rate portion of the total in-reactor behavior observed. The thermal component was observed to recur upon reloading, giving rise to a significantly enhanced creep rate for cyclic loadings.
Analysis of In-Reactor Stress Relaxation Using Irradiation Creep Models
Authors: Foster JP 
Published: March 2009

Irradiation creep and stress relaxation data are available from the United Kingdom for 20 percent cold-worked Type M316, 20 percent cold-worked Type FV548, and FHT Type PE-16 using pure torsion in the absence of swelling at 300 °C (572 °F). Irradiation creep models were used to calculate the relaxation and permanent deflection of the stress relaxation tests. Two relationships between irradiation creep and stress relaxation were assessed by comparing the measured and calculated stress relaxation and permanent deflection. The results show that for Types M316 and FV548 the stress relaxation and deflection may be calculated using irradiation creep models when the stress rate term arising from the irradiation creep model is set equal to zero. In the case of Type PE-16, the inability to calculate the stress relaxation and permanent deflection from the irradiation creep data was attributed to differences in creep behavior arising from lot-to-lot variations in alloying elements and impurity content.
A modification of Types FV548 and PE-16 irradiation creep coefficients was necessary in order to calculate the stress relaxation and deflection. The modifications in Types FV548 and PE-16 irradiation creep properties reduces the large variation in the transient or incubation parameter predicted by irradiation creep tests for Types M316, FV548, and PE-16.
Effect of Fast Reactor Irradiation on the Tensile Properties of 20 Percent Cold-Worked Type 316 Stainless Steel
Authors: Fish RL , Watrous JD 
Published: March 2009

Fast neutron irradiation effects on the tensile properties of 20 percent cold-worked Type 316 stainless steel are presented to fluences of 3.6 × 1022 neutrons (n)/cm2, E &gt; 0.1 MeV (3.6 × 1026 n/m2, E &gt; 16 fJ), at irradiation temperatures of 700 to 1125°F (644 to 880 K). The tests were performed over the range of room temperature to 1600°F (1144 K) employing strain rates of 1.82 × 10-3 to 1.82/min (3 × 10-5 to 3 × 10-2/s).
Irradiation defect hardening at irradiation temperatures below 900°F (755 K) resulted in strength increases. Thermal annealing of the original cold-work operated to reduce the strength of material irradiated near 1000 and 1100°F (811 and 866 K), in the fluence range investigated. Elongation values initially increased at most irradiation temperatures and then decreased with fluence beyond 1022 n/cm2 (1026 n/m2). Both strength and ductility decreased with increasing temperature at fluences beyond 1022 n/cm2 (1026 n/m2). The 450°F (505 K) unirradiated elongation level was maintained or improved for all irradiation conditions investigated, which suggests that low ductility will not present a problem during refueling operations.
Tensile Properties of Fast Reactor Irradiated Type 304 Stainless Steel
Authors: Fish RL , Hunter CW 
Published: March 2009

Tension tests were performed on annealed Type 304 stainless steel specimens sectioned from Experimental Breeder Reactor-II (EBR-II) duct thimbles. The specimens had accumulated neutron fluences of up to 10.3 × 1022 neutrons (n)/cm2, E &gt; 0.1 MeV (10.3 × 1026 n/m2, E ×16 fJ). Irradiation temperatures for the material tested ranged from 700 to 750°F (644 to 672 K). The tests were performed at temperatures of room temperature to 1400°F (1033 K), employing strain rates of 2 × 10-3 to 2/min (3.3 × 10-5 to 3.3 × 10-2/s).
At test temperatures below 800°F (700 K), the strength increased with fluence until about 7 × 1022 n/cm2 (7 × 1026 n/m2), beyond which no further increase was observed. The elongation decreased with fluence, reaching levels as low as 0.5 percent uniform and 1.3 percent total elongation at 700°F (644 K). High-fluence failures below 800°F (700 K) occurred by transgranular channel fracture.
At test temperatures above 1000°F (811 K), elongations were reduced to very low levels at high fluences (average total elongation (TE) = 0.03 percent). Extensive intergranular fracture at the high fluences produced the low ductility and resulted in failure of the specimens before reaching the strength characteristic of the true hardness of the material.
Effects of Neutron Irradiation on Microstructure and Mechanical Properties of Nimonic PE-16
Authors: Sklad PS , Clausing RE , Bloom EE 
Published: March 2009

Specimens of Nimonic PE-16, a γ'-hardened austenitic alloy, were irradiated in the Experimental Breeder Reactor-II (EBR-II) in order to determine the effect of neutron irradiation on the microstructure and mechanical properties. Specimens with two different aging treatments were irradiated at temperatures ranging from 650 to 823 K and fluences ranging from 1.2 × 1026 neutrons (n)/m2 to 4.0 × 1026 n/m2. The aging treatments were: (A) 2h at 1313 K + 2 h at 1073 K + 16 h at 973 K; and (B) 4 h at 1313 K + 1 h at 1173 K + 8 h at 1023 K. Postirradiation transmission electron microscopy (TEM) revealed the presence of voids in all irradiated specimens. No difference in the fluence dependence of swelling at an irradiation temperature of 773 K was observed between the specimens with Preirradiation Treatment A and the specimens with Preirradiation Treatment B. In contrast, the temperature dependence of swelling appears to be sensitive to the particular preirradiation aging treatment used. TEM also shows that existing precipitates coarsen slightly during irradiation and that precipitation of γ'-precipitates occurs on irradiation-produced dislocation loops and voids.
Specimens irradiated at 773 K were tensile tested at 683, 773, 873, and 973 K. There is no significant difference in postirradiation mechanical properties between the two preirradition heat treatments. There is a large increase in yield strength after irradiation, which is consistent with the observed changes in microstructure. The ductility decreases as the test temperature increases. The low ductilities observed at the higher test temperatures are associated with a tendency for intergranular fracture. Auger spectroscopy of fracture surfaces on a specimen fractured at 823 to 873 K in the Auger chamber indicates that the concentrations of phosphorus and sulfur are a factor of two or three higher, and that the concentrations of iron and chromium are a factor of two lower, on surfaces of grain boundary fracture than on surfaces resulting from ductile fracture within the same specimen. There is also an enrichment of nickel at grain boundaries. In addition, helium release was observed at the time of fracture.
Swelling and Gamma-Prime Particle Stability of Ion-Bombarded Iron-Chromium-Nickel Alloys
Authors: Bleiberg ML , Bajaj R , Baron IM , Chang A , Chickering RW , Diamond S 
Published: March 2009

Nickel-ion bombardment studies were conducted on experimental alloys which were designed to provide basic information on the influence of composition, residual elements, and γ'-precipitates on swelling in the iron-chromium-nickel alloy system. Bombardments were conducted at temperatures ranging from 550 to 750°C (1022 to 1382°F) to maximum damage of 250 displacements per atom (dpa).
Comparison of identical alloys with and without γ'-precipitates showed that titanium and aluminum additions to the matrix compositions suppressed swelling. It is inferred that the aluminum increases the incubation dose while titanium reduces the swelling rate. The γ'-precipitates influence swelling only as they affect matrix chemistry.
Fine γ'-particles (8 to 18 nm) were precipitated under irradiation and approached an equilibrium size at high damage levels. A slight coarsening of 30-nm particles was observed, but there was only a slight increase in the volume fraction of the γ'-particles due to the irradiation. It was concluded that disorder dissolution was not an important mechanism in these alloys.
Nickel-Ion Damage in a Precipitation-Hardened Nickel-Aluminum
Authors: Kirchner LG , Smidt FA , Kulcinski GL , Sprague JA , Westmoreland JE 
Published: March 2009

A precipitation-hardened nickel 14 atom percent aluminum alloy has been irradiated with 2.8 MeV 58Ni+ ions at a damage rate of 4.4 × 10-2 displacements per atom (dpa)/s, over a temperature range of 525 to 725 °C (977 to 1337 °F), to a damage level of 20 dpa, and at 625 °C (1157°F) over a dose range of 4 to 125 dpa. The experiment was designed to examine the stability of Ni3Al precipitates as a function of temperature and dose as well as their role in reducing swelling.
Prior to irradiation, the precipitates were cuboidal in shape with a mean edge length of 400 Å. Ion bombardment to 20 dpa at 725 °C (1337 °F) generated a higher precipitate density with a reduced and highly uniform size of 85 Å. At all other temperatures, the precipitate structures were less well defined and took on a ragged appearance with a wide spread in sizes as small precipitates formed between the original ones. A few scattered voids were formed at the two highest damage levels at 625 °C (1157 °F), but the swelling was negligible.