8,833 research outputs found
Two leaf beetles new to Florida (Coleoptera: Chrysomelidae)
Specimens recently submitted to the first author for identification turned out to represent two species of leaf beetles previously unknown from Florida, one of which is new to the eastern United States and the other new to the continental United States
A time dependent relation between EUV solar flare light-curves from lines with differing formation temperatures
Extreme ultraviolet (EUV) solar flare emissions evolve in time as the
emitting plasma heats and then cools. Although accurately modeling this
evolution has been historically difficult, especially for empirical
relationships, it is important for understanding processes at the Sun, as well
as for their influence on planetary atmospheres. With a goal to improve
empirical flare models, a new simple empirical expression is derived to predict
how cool emissions will evolve based on the evolution of a hotter emission.
This technique is initially developed by studying 12 flares in detail observed
by the EUV Variability Experiment (EVE) onboard the Solar Dynamics Observatory
(SDO). Then, over 1100 flares observed by EVE are analyzed to validate these
relationships. The Cargill and Enthalpy Based Thermal Evolution of Loops
(EBTEL) flare cooling models are used to show that this empirical relationship
implies the energy radiated by a population of hotter formed ions is
approximately proportional to the energy exciting a population of cooler formed
ions emitting when the peak formation temperatures of the two lines are up to
72% of each other and above 2 MK. These results have practical implications for
improving flare irradiance empirical modeling and for identifying key emission
lines for future monitoring of flares for space weather operations; and also
provide insight into the cooling processes of flare plasma.Comment: Final version accepted for publication by the Journal of Space
Weather and Space Climate on 23 November 201
Modeling services liberalization : the case of Kenya
This paper employs a 55 sector small open economy computable general equilibrium model of the Kenyan economy to assess the impact of the liberalization of regulatory barriers against foreign and domestic business service providers in Kenya. The model incorporates productivity effects in both goods and services markets endogenously, through a Dixit-Stiglitz framework. It estimates the ad valorem equivalent of barriers to foreign direct investment based on detailed questionnaires completed by specialists in Kenya. The authors estimate that Kenya will gain about 11 percent of the value of Kenyan consumption in the medium run (or about 10 percent of gross domestic product) from a full reform package that also includes uniform tariffs. The estimated gains increase to 77 percent of consumption in the long-run steady-state model, where the impact on the accumulation of capital from an improvement in the productivity of capital is taken into account. Decomposition exercises reveal that the largest gains to Kenya will derive from liberalization of costly regulatory barriers that are non-discriminatory in their impacts between Kenyan and multinational service providers.Transport Economics Policy&Planning,Economic Theory&Research,Banks&Banking Reform,Emerging Markets,Debt Markets
What is the object of the encapsulation of a process?
Several theories have been proposed to describe the transition from process to object in mathematical thinking. Yet, what is the nature of this ''object'' produced by the ''encapsulation'' of a process? Here, we outline the development of some of the theories (including Piaget, Dienes, Davis, Greeno, Dubinsky, Sfard, Gray, and Tall) and consider the nature of the mental objects (apparently) produced through encapsulation and their role in the wider development of mathematical thinking. Does the same developmental route occur in geometry as in arithmetic and algebra? Is the same development used in axiomatic mathematics? What is the role played by imagery
Localizing international education agendas: Boys (still) underachieving in Jamaica’s secondary education
The literature on basic education emphasizes the need to improve enrollment and access to girls’ education in poorer countries. In Jamaica, the problem is not merely access to basic education but rather the quality of education outcomes, particularly for boys. Setting my research findings within the context of globalization and basic education, this paper explores the underachievement of boys within the contexts of international education policies at the domestic/national scale in Jamaica. Using a combination of participants’ responses drawn from semi-structured interviews conducted with teachers across two rural high schools in Jamaica, an analysis of secondary sources and (to a lesser extent) participant observations, we put forward a few claims regarding the process of ‘localizing’ ‘international’ education. It appears that global discourses in education (education for all) place demands on the local context – privilege girls, and the problem of lack of access to education and the overall the quality of experience. And therefore, the Jamaican state can ‘evade’ or palliatively address the ongoing problem of boys’ underachievement. The paper also highlights the effects of neoliberal restructuring in education as well as the inconsistencies between domestic/national and international education policies
Drogue Measurements of the Circulation in Grand Traverse Bay, Lake Michigan
http://deepblue.lib.umich.edu/bitstream/2027.42/96600/1/39015087358480.pd
100 Years of Credit Unions: Impact of Tax Exempt Status The Case for Georgia
Thomas G. Noland Ph.D., CPA, CMA, CDFM, is associate professor of accounting in the Mitchell College of Business, University of South Alabama, Mobile, AL 36688-0002.
Edward H. Sibbald is BB&T Executive in residence in banking and director for the Center for Excellence in Financial Services in the College of Business Administration, Georgia Southern University, Statesboro, GA 30460-8151
The Performance of Concrete in a Marine Environment
This paper presents a summary of data from wide range of concretes following periods of marine exposure ranging up to 25 years. Data are presented from more than 100 different concrete mixtures. The various types of concrete include fibre-reinforced concrete (FRC), ultra-high performance concrete (UHPC), concrete with a range of supplementary cementing materials (SCM such as fly ash, slag, and silica fume) and replacement levels (e.g. up to 58% fly ash and 80% slag), lightweight-aggregate concrete (LWAC) and concrete containing alkali-silica reactive aggregate. Testing included measuring chloride concentration profiles, electrochemical corrosion measurements (for steel-reinforced concrete), and various electrical and mechanical properties, in addition to the examination of the microstructure. The data invariably show the importance of the binder type in terms of resistance to chloride ingress and the protection conferred on embedded steel reinforcement, however, the overall performance of SCM concrete was equivocal as high replacement levels were observed to lead to increased surface deterioration (scaling) in some cases. The performance of UHPC was exemplary with little significant chloride penetration and no evidence of surface deterioration after up to 20 years exposure and an estimated 2,000+ freeze-thaw cycles. Expansion (and cracking) due to alkali-silica reaction was observed to be reduced by seawater exposure but, perhaps more significantly, render air-entrained concrete highly susceptible to freeze-thaw damage when the expansion exceeded a certain threshold value. The data are discussed in terms of code requirements and the need for appropriate performance testing. The importance of long-term monitoring of concrete on exposure sites is also discussed
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