3,858 research outputs found
Observations of stratospheric temperature changes coincident with the recent Antarctic ozone depletions
A high degree of correlation between the recent decline in Antarctic total ozone and cooling of the stratosphere during Austral spring has been noted in several recent studies (e.g., Sekiguchi, 1986; Angel, 1986). This study analyzes the observed temperature trends in detail, focusing on the spatial and temporal aspects of the observed cooling. Ozone losses and stratospheric cooling can be correlated for several reasons: (1) ozone losses (from an unspecified cause) will directly reduce temperatures due to decreased solar ultraviolet absorption (Shine, 1986), and/or (2) changes in both ozone and temperature structure due to modification of stratospheric circulation patterns (Mahlman and Fels, 1986). In order to scrutinize various ozone depletion scenarios, detailed information on the observed temperature changes is necessary; the goal is to provide such data. The data used are National Meteorological Center (NMC) Climate Analysis Center (CAC) derived temperatures, covering 1000 to 1 mb (0 to 48 km), for the period 1979 to 1987. Discussions on data origin and quality (assessed by extensive comparisons with radiosonde observations), along with other details of these observations, can be found in Newman and Randel (1988)
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Teaching Design in visual basic programming environments using the NEADT 3 rapid application design tool
Although program design and documentation tools have existed for over 30 years, virtually no tools other than the Task-Object-Event (TOE) chart have been created for teaching program design in the event-driven object-oriented language environment. This paper discusses the NEADT3 (Newman-Ekedahl Application Development tool) applied to the Visual Basic 6.0 language. NEADT 3 Significantly extends the commonly used TOE model in teaching programming by providing more concise and correct design and documentation of Rapid Application Development (RAD) student programs
The Proposed Housing Consolidation and Simplification Act of 1971
This note will describe the operation of selected housing programs and suggest some of the difficulties posed by the current statutory bases for these programs. It will then evaluate the effectiveness of the modifications contained in the proposed bill
A New and Primitive Barnacle (Cirripedia: Balanomorpha) from the North Fiji Basin Abyssal Hydrothermal Field, and Its Evolutionary Implications
A new sessile barnacle, Eochionelasmus ohtai, n. gen., n. sp., has
been discovered associated with an abyssal hydrothermal vent at 1990m depth in
the North Fiji Basin, Southwest Pacific. The genus is distinguished from its
closest and bathyal relative, Chionelasmus, in having distinct, multiple whorls of
basal imbricating plates. These and other characters render it the most primitive
living member of the suborder Balanomorpha. Knowledge of the organization of
its shell, and of the ontogeny of the shell wall in Chionelasmus, profoundly alters
our understanding of the evolution of balanomorph barnacles, and a new
hypothesis is proposed. Two previously described abyssal hydrothermal barnacles
also proved to represent the most primitive living members of their suborder
s: Scalpellomorpha and Verrucomorpha. It may be puzzling why three such
antiquated morphologies should have persisted in association with abyssal
hydrothermal springs while their antecedents became extinct elsewhere. However,
barnacles are noted f(or their adaptability to a wide range of habitats
including rigorous environments such as estuaries, the highest intertidal, and the
effluent from power plants. The notable feature here, in contrast to their conservative
but distinctly different shell morphologies, is the uniquely convergent
adaptation of their setose feeding mechanism to vent-related food sources
An Experiential Supply Chain Management Field Study: Effectively Bridging the Gap Between Classroom and Practice
Employers want new college graduates to relate theory to practice when they begin their careers. Experiential learning opportunities provide occasions to develop such skills. However, internships and single factory tours rarely provide more generalizable insights about the competitive nature of business across a range of firms. We conceptually explore an experiential field study that addresses this shortcoming: a supply chain management course of the brewing industry. We describe the development of our course, its execution, its learning outcomes, advantages of our approach in the brewing industry, and suggestions to replicate it at other schools and with other industries
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The object-oriented paradigm as an implementation of systems theory in IS
Classical General Systems Theory (GST) is rich with fundamental concepts relating to the explanation of how systems behave and operate. The new concept of object-oriented techniques and methodologies was found to be closely aligned with most of the fundamental theories of GST. This article presents these alignments and similarities and clearly shows that object-oriented techniques provide a better fit to GST than older design methodologies
Testing Recognition of Computer-generated Icons
Icons have been popularized by modern Graphical User Interface (GUI) software, however, an individual\u27s use and reaction to icons varies. Our purpose was to demonstrate that a computerized recall and recognition survey of icons could produce measurable results that could be used to better design and choose icons for common microcomputer applications. Icons with better recognition would also aid in student learning of common software tools. For this pilot survey, 125 MIS students viewed a projected five-minute computerized VGA slide show in a darkened classroom. Looking at a sequence of 30 colored screens shown for only 10 seconds each, they indicated their preferences for and their ability to discriminate, recall, and recognize 48 icons. The results indicated individuals can make icon choices quickly, certainly have icon preferences, and can recognize icons that they saw for only 10 seconds. Computerized projected surveys can provide preferences and measurable performance (number correct per time period) for icons, trademarks, logos, and signals much quicker than a series of individual trials or surveys
Evaluation of a Small-Crack Monitoring System
A new system has been developed to obtain fatigue crack growth rate data from a series of images acquired during fatigue testing of specimens containing small surface cracks that initiate at highly-polished notches. The primary benefit associated with replica-based crack growth rate data methods is preserving a record of the crack configuration during the life of the specimen. Additionally, this system has the benefits of both reducing time and labor, and not requiring introduction of surface replica media into the crack. Fatigue crack growth rate data obtained using this new system are found to be in good agreement with similar results obtained from surface replicas
Fatigue Crack Closure Analysis Using Digital Image Correlation
Fatigue crack closure during crack growth testing is analyzed in order to evaluate the critieria of ASTM Standard E647 for measurement of fatigue crack growth rates. Of specific concern is remote closure, which occurs away from the crack tip and is a product of the load history during crack-driving-force-reduction fatigue crack growth testing. Crack closure behavior is characterized using relative displacements determined from a series of high-magnification digital images acquired as the crack is loaded. Changes in the relative displacements of features on opposite sides of the crack are used to generate crack closure data as a function of crack wake position. For the results presented in this paper, remote closure did not affect fatigue crack growth rate measurements when ASTM Standard E647 was strictly followed and only became a problem when testing parameters (e.g., load shed rate, initial crack driving force, etc.) greatly exceeded the guidelines of the accepted standard
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