Chemistry in the year 2000: Recruiting students for the 21st century

1986 ◽  
Vol 63 (6) ◽  
pp. 496
Author(s):  
David J. Ager ◽  
Julian A. Davies ◽  
Alan R. Morgan
Keyword(s):  
21St Century ◽  
Year 2000

scholarly journals Inlet and Nozzle Technology for 21st Century Fighter Aircraft

1996 ◽  
Author(s):  
Marvin C. Gridley ◽  
Steven H. Walker
Keyword(s):  
21St Century ◽  
Cost Reduction ◽  
State Of The Art ◽  
Aerodynamic Performance ◽  
Innovative Technology ◽  
Fighter Aircraft ◽  
Current State ◽  
Aircraft System ◽  
Year 2000 ◽  
System Volume

The focus of propulsion integration technology in the 21st century will be economy. USAF inlet and nozzle technology goals translate into 50% weight reduction and 25% acquisition cost reduction metrics for new aircraft system. Innovative technology to enable these reductions over current state-of-the-art systems in weight and cost is required. For inlet systems, compact diffusers that reduce system volume by 50% will demand fewer parts and improved aerodynamic performance. Exhaust systems will be fixed with fewer parts, requiring a technology like fluidics, for example, to provide area control and thrust vectoring capabilities. Cooperative programs for both inlet and nozzle systems are in place to insure that technologies required to meet weight and cost reduction goals are matured by the year 2000.

scholarly journals Key drivers of ozone change and its radiative forcing over the 21st century

2018 ◽  
Vol 18 (9) ◽  
pp. 6121-6139 ◽  
Author(s):  
Fernando Iglesias-Suarez ◽  
Douglas E. Kinnison ◽  
Alexandru Rap ◽  
Amanda C. Maycock ◽  
Oliver Wild ◽  
...  
Keyword(s):  
Climate Change ◽  
21St Century ◽  
Radiative Forcing ◽  
Climate Model ◽  
Stratospheric Ozone ◽  
Atmospheric Composition ◽  
Climate Conditions ◽  
Radiative Balance ◽  
Radiative Forcings ◽  
Year 2000

Abstract. Over the 21st century changes in both tropospheric and stratospheric ozone are likely to have important consequences for the Earth's radiative balance. In this study, we investigate the radiative forcing from future ozone changes using the Community Earth System Model (CESM1), with the Whole Atmosphere Community Climate Model (WACCM), and including fully coupled radiation and chemistry schemes. Using year 2100 conditions from the Representative Concentration Pathway 8.5 (RCP8.5) scenario, we quantify the individual contributions to ozone radiative forcing of (1) climate change, (2) reduced concentrations of ozone depleting substances (ODSs), and (3) methane increases. We calculate future ozone radiative forcings and their standard error (SE; associated with inter-annual variability of ozone) relative to year 2000 of (1) 33 ± 104 m Wm−2, (2) 163 ± 109 m Wm−2, and (3) 238 ± 113 m Wm−2 due to climate change, ODSs, and methane, respectively. Our best estimate of net ozone forcing in this set of simulations is 430 ± 130 m Wm−2 relative to year 2000 and 760 ± 230 m Wm−2 relative to year 1750, with the 95 % confidence interval given by ±30 %. We find that the overall long-term tropospheric ozone forcing from methane chemistry–climate feedbacks related to OH and methane lifetime is relatively small (46 m Wm−2). Ozone radiative forcing associated with climate change and stratospheric ozone recovery are robust with regard to background climate conditions, even though the ozone response is sensitive to both changes in atmospheric composition and climate. Changes in stratospheric-produced ozone account for ∼ 50 % of the overall radiative forcing for the 2000–2100 period in this set of simulations, highlighting the key role of the stratosphere in determining future ozone radiative forcing.

Cloud Computing in the 21st Century

2019 ◽  
pp. 1734-1747
Author(s):  
Mahesh S. Raisinghani ◽  
Efosa Carroll Idemudia ◽  
Meghana Chekuri ◽  
Kendra Fisher ◽  
Jennifer Hanna
Keyword(s):  
Cloud Computing ◽  
Competitive Advantage ◽  
21St Century ◽  
Top Management Teams ◽  
Steady Increase ◽  
Process Data ◽  
Bottom Line ◽  
Business Plans ◽  
Year 2000 ◽  
Managerial Perspective

The constant changes in technology has posed serious challenges to top management teams, employees, and customers on how to collect, store, and process data for competitive advantage and to make better decisions. In this chapter, to address this issue, we present the managerial perspective of cloud computing that provides the infrastructure and/or tools for decision making in the 21st century. Since the year 2000, the interest in cloud computing has had a steady increase. (Mason, 2002) Not only has cloud computing substantially lowered computing costs for corporations, it continues to increase their abilities for market offerings and to access customers' information with ease. Cloud computing has allowed managers to focus more on their business plans and bottom line to enhance competitive advantage.

scholarly journals Spaanse vreemde woorden in het Nederlands periode 2000-2013. Aanvullingen op de Dikke Van Dale

2014 ◽  
pp. 373-391
Author(s):  
Francisco Sánchez Romero
Keyword(s):  
21St Century ◽  
Native Speakers ◽  
Semantic Fields ◽  
Cultural Method ◽  
Year 2000

t Toe purpose of this research is to look into the recent influence of Spanish, both peninsular and from the centre and south of America, (approximately 400 million native speakers altogether) on Dutch (23 million). Spanish foreign words will be analyzed according to the European historical-cultural method, this is, they will be dealt with within a historical frame (in this case from the year 2000). By creating a corpus of Spanish foreign words, I will try to clarify which are the most influential semantic fields on Dutch nowadays. From this division into semantic fields, it will be possible to see what kind of vocabulary has been influential and which has been the degree of contact during the first thirteen years of 21st century.

scholarly journals Morphology and Syntax in Holes and Scratches: The Latest Stage of Kugyol Research

2011 ◽  
Vol 1 (1) ◽  
pp. 53-70
Author(s):  
Yong LEE
Keyword(s):  
21St Century ◽  
History Of ◽  
Chinese Texts ◽  
Year 2000

The first part of this article reviews the differences between the Chinese, Korean and Japanese languages, and explains the importance of Buddhist texts in the history of these languages, especially in the development of written languages in Korea and Japan. The kugyol tradition (a convention for adding Korean grammatical markers at appropriate places to aid the reading of originally Chinese texts) is then explained with concrete examples in three parts: eumdok kugyol (transliteration kugyol), seokdok kugyol (translation kugyol), and jeomto seokdok-kugyol (traslation kugyol with point marks). The latest developments in kugyol research were seen in the 21st century, after the discovery of Yugasijiron in the year 2000, including the detailed point maps. Some questions concerning the jeomto seokdok-kugyol are still open.

scholarly journals Key drivers of ozone change and its radiative forcing over the 21st century

2017 ◽  
Author(s):  
Fernando Iglesias-Suarez ◽  
Douglas E. Kinnison ◽  
Alexandru Rap ◽  
Oliver Wild ◽  
Paul J. Young
Keyword(s):  
Climate Change ◽  
21St Century ◽  
Radiative Forcing ◽  
Climate Model ◽  
Stratospheric Ozone ◽  
Atmospheric Composition ◽  
Radiative Balance ◽  
Uncertainty Range ◽  
Ozone Depleting Substances ◽  
Year 2000

Abstract. Over the 21st century changes in both tropospheric and stratospheric ozone are likely to have important consequences for the Earth's radiative balance. In this study we investigated the radiative effects of future ozone changes, using the Community Earth System Model (CESM1), with the Whole Atmosphere Community Climate Model (WACCM), and including fully coupled radiation and chemistry schemes. Using year 2100 conditions from the Representative Concentration Pathways 8.5 (RCP8.5) scenario, we quantified the individual contributions to ozone radiative forcing of (1) climate change (with and without lightning feedback), (2) reduced concentrations of ozone depleting substances (ODSs), and (3) methane increases. We calculated future ozone radiative forcing relative to year 2000 of (1) 63 ± 76 m Wm−2, (2) 129 ± 81 m Wm−2, and (3) 225 ± 85 m Wm−2, due to climate change, ODSs and methane respectively. Our best estimate of net ozone forcing in this set of simulations is 420 ± 120 m Wm−2 relative to year 2000, and 750 ± 230 m Wm−2 relative to year 1750, with uncertainty range given by approximately ±30 %. We find that the overall long-term tropospheric ozone forcing from methane chemistry-climate feedbacks related to OH and methane lifetime is small (46 m Wm−2). Ozone forcings associated with climate change and stratospheric ozone recovery are robust with regard to background conditions, even though the ozone response is sensitive to both changes in atmospheric composition and climate. Changes in stratospheric-produced ozone account for ~ 47 % of the overall radiative forcing in this set of simulations, highlighting the key role of the stratosphere in determining future radiative forcing.

scholarly journals Contributions to stratospheric ozone changes from ozone depleting substances and greenhouse gases

2010 ◽  
Vol 10 (4) ◽  
pp. 9647-9694 ◽  
Author(s):  
D. A. Plummer ◽  
J. F. Scinocca ◽  
T. G. Shepherd ◽  
M. C. Reader ◽  
A. I. Jonsson
Keyword(s):  
Greenhouse Gases ◽  
21St Century ◽  
Climate Model ◽  
Stratospheric Ozone ◽  
Three Dimensional ◽  
Ocean Model ◽  
Residual Circulation ◽  
Chemical Effects ◽  
Ozone Depleting Substances ◽  
Year 2000

Abstract. A state-of-the-art chemistry climate model coupled to a three-dimensional ocean model is used to produce three experiments, all seamlessly covering the period 1950–2100, forced by different combinations of long-lived Greenhouse Gases (GHGs) and Ozone Depleting Substances (ODSs). The experiments are designed to investigate the mechanisms by which GHGs and ODSs affect the evolution of ozone, including changes in the Brewer-Dobson circulation of the stratosphere and cooling of the upper stratosphere by CO2. Separating the effects of GHGs and ODSs on ozone, we find the decrease in upper stratospheric ozone from ODSs up to the year 2000 is approximately 30% larger than the actual decrease in ozone due to the offsetting effects of cooling by increased CO2. Over the 21st century, as ODSs decrease, continued cooling from CO2 is projected to account for more than 50% of the projected increase in upper stratospheric ozone. Changes below 20 hPa show a redistribution of ozone from tropical to extra-tropical latitudes with an increase in the Brewer-Dobson circulation, while globally averaged the amount of ozone below 20 hPa decreases over the 21st century. Further analysis by linear regression shows that changes associated with GHGs do not appreciably alter the recovery of stratospheric ozone from the effects of ODSs; over much of the stratosphere ozone recovery follows the decline of halogen concentrations within statistical uncertainty, though the lower polar stratosphere of the Southern Hemisphere is an exception with ozone concentrations recovering more slowly than indicated by the halogen concentrations. These results also reveal the degree to which climate change, and stratospheric CO2 cooling in particular, mutes the chemical effects of N2O on ozone in the standard future scenario used for the WMO Ozone Assessment. Increases in the residual circulation of the atmosphere and chemical effects from CO2 cooling more than halve the increase in reactive nitrogen in the mid to upper stratosphere that results from the specified increase in N2O between 1950 and 2100.

Cloud Computing in the 21st Century

2015 ◽  
pp. 188-200 ◽  
Author(s):  
Mahesh S. Raisinghani ◽  
Efosa Carroll Idemudia ◽  
Meghana Chekuri ◽  
Kendra Fisher ◽  
Jennifer Hanna
Keyword(s):  
Cloud Computing ◽  
Competitive Advantage ◽  
21St Century ◽  
Top Management Teams ◽  
Steady Increase ◽  
Process Data ◽  
Bottom Line ◽  
Business Plans ◽  
Year 2000 ◽  
Managerial Perspective

The constant changes in technology has posed serious challenges to top management teams, employees, and customers on how to collect, store, and process data for competitive advantage and to make better decisions. In this chapter, to address this issue, we present the managerial perspective of cloud computing that provides the infrastructure and/or tools for decision making in the 21st century. Since the year 2000, the interest in cloud computing has had a steady increase. (Mason, 2002) Not only has cloud computing substantially lowered computing costs for corporations, it continues to increase their abilities for market offerings and to access customers' information with ease. Cloud computing has allowed managers to focus more on their business plans and bottom line to enhance competitive advantage.

Computers in Health Care for the 21st Century

1990 ◽  
Vol 29 (02) ◽  
pp. 158-161 ◽  
Author(s):  
R. I. O’Desky ◽  
M. J. Ball ◽  
E. E. Ball
Keyword(s):  
Health Care ◽  
20Th Century ◽  
21St Century ◽  
Delivery Of Health Care ◽  
Health Care Systems ◽  
Computer Technologies ◽  
The World ◽  
The Future ◽  
Care Systems ◽  
Year 2000

AbstractAs the world enters the last decade of the 20th Century, there is a great deal of speculation about the effect of computers on the future delivery of health care. In this article, the authors attempt to identify some of the evolving computer technologies and anticipate what effect they will have by the year 2000. Rather than listing potential accomplishments, each of the affected areas: hardware, software, health care systems and communications, are presented in an evolutionary manner so the reader can better appreciate where we have been and where we are going.

scholarly journals The IAU in the 21st Century

2018 ◽  
Vol 13 (S349) ◽  
pp. 58-60
Author(s):  
Robert Williams
Keyword(s):  
United Nations ◽  
21St Century ◽  
Strategic Plan ◽  
The Public ◽  
The World ◽  
The United Nations ◽  
Year 2000

AbstractBeginning in year 2000 the IAU undertook a number of initiatives that changed the Union from being primarily an inward-focused organization whose emphasis was the world of professional astronomy, to being more outward looking in engaging with the public. These initiatives included proposing to the United Nations and then leading the International Year of Astronomy IYA 2009, and the formulation of a Strategic Plan that included creation of the Office of Astronomy for Development. Additional programs are being undertaken by the Union that continue to broaden IAU engagement with the public.

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