153 research outputs found

    Tropospheric Carbon Monoxide Measurements from the Scanning High-Resolution Interferometer Sounder on 7 September 2000 in Southern Africa During SAFARI 2000

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    [1] Retrieved tropospheric carbon monoxide (CO) column densities are presented for more than 9000 spectra obtained by the University of Wisconsin-Madison (UWis) Scanning High-Resolution Interferometer Sounder (SHIS) during a flight on the NASA ER-2 on 7 September 2000 as part of the Southern African Regional Science Initiative (SAFARI 2000) dry season field campaign. Enhancements in tropospheric column CO were detected in the vicinity of a controlled biomass burn in the Timbavati Game Reserve in northeastern South Africa and over the edge of the river of smoke in south central Mozambique. Relatively clean air was observed over the far southern coast of Mozambique. Quantitative comparisons are presented with in situ measurements from five different instruments flying on two other aircraft: the University of Washington Convair-580 (CV) and the South African Aerocommander JRB in the vicinity of the Timbavati fire. Measured tropospheric CO columns (extrapolated from 337 to 100 mb) of 2.1 × 1018 cm−2 in background air and up to 1.5 × 1019 cm−2 in the smoke plume agree well with SHIS retrieved tropospheric CO columns of (2.3 ± 0.25) × 1018 cm−2 over background air near the fire and (1.5 ± 0.35) × 1019 cm−2 over the smoke plume. Qualitative comparisons are presented with three other in situ CO profiles obtained by the South African JRA aircraft over Mozambique and northern South Africa showing the influence of the river of smoke

    The Southern African Regional Science Initiative (SAFARI 2000): Overview of the Dry Season Field Campaign

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    The Southern African Regional Science Initiative (SAFARI 2000) is an international science project investigating the earth-atmosphere-human system in southern Africa. The programme was conducted over a two-year period from March 1999 to March 2001. The dry season field campaign (August-September 2000) was the most intensive activity and involved over 200 scientists from eighteen countries. The main objectives were to characterize and quantify biogenic, pyrogenic and anthropogenic aerosol and trace gas emissions and their transport and transformations in the atmosphere, and to validate NASA\u27s Earth Observing System\u27s satellite Terra within a scientific context. Five aircraft - two South African Weather Service Aerocommanders, the University of Washington\u27s CV-580, the U.K. Meteorological Office\u27s C-130, and NASA\u27s ER-2-with different altitude capabilities, participated in the campaign. Additional airborne sampling of southern African air masses, that had moved downwind of the subcontinent, was conducted by the CSIRO over Australia. Multiple observations were made in various geographical sectors under different synoptic conditions. Airborne missions were designed to optimize the value of synchronous over-flights of the Terra satellite platform, above regional ground validation and science targets. Numerous smaller-scale ground validation activities took place throughout the subcontinent during the campaign period

    Scenario-Based Design Theorizing:The Case of a Digital Idea Screening Cockpit

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    As ever more companies encourage employees to innovate, a surplus of ideas has become reality in many organizations – often exceeding the available resources to execute them. Building on insights from a literature review and a 3-year collaboration with a banking software provider, the paper suggests a Digital Idea Screening Cockpit (DISC) to address this challenge. Following a design science research approach, it suggests a prescriptive design theory that provides practitioner-oriented guidance for implementing a DISC. The study shows that, in order to facilitate the assessment, selection, and tracking of ideas for different stakeholders, such a system needs to play a dual role: It needs to structure decision criteria and at the same be flexible to allow for creative expression. Moreover, the paper makes a case for scenario-based design theorizing by developing design knowledge via scenarios

    A study to derive a clinical decision rule for triage of emergency department patients with chest pain: design and methodology

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    <p>Abstract</p> <p>Background</p> <p>Chest pain is the second most common chief complaint in North American emergency departments. Data from the U.S. suggest that 2.1% of patients with acute myocardial infarction and 2.3% of patients with unstable angina are misdiagnosed, with slightly higher rates reported in a recent Canadian study (4.6% and 6.4%, respectively). Information obtained from the history, 12-lead ECG, and a single set of cardiac enzymes is unable to identify patients who are safe for early discharge with sufficient sensitivity. The 2007 ACC/AHA guidelines for UA/NSTEMI do not identify patients at low risk for adverse cardiac events who can be safely discharged without provocative testing. As a result large numbers of low risk patients are triaged to chest pain observation units and undergo provocative testing, at significant cost to the healthcare system. Clinical decision rules use clinical findings (history, physical exam, test results) to suggest a diagnostic or therapeutic course of action. Currently no methodologically robust clinical decision rule identifies patients safe for early discharge.</p> <p>Methods/design</p> <p>The goal of this study is to derive a clinical decision rule which will allow emergency physicians to accurately identify patients with chest pain who are safe for early discharge. The study will utilize a prospective cohort design. Standardized clinical variables will be collected on all patients at least 25 years of age complaining of chest pain prior to provocative testing. Variables strongly associated with the composite outcome acute myocardial infarction, revascularization, or death will be further analyzed with multivariable analysis to derive the clinical rule. Specific aims are to: i) apply standardized clinical assessments to patients with chest pain, incorporating results of early cardiac testing; ii) determine the inter-observer reliability of the clinical information; iii) determine the statistical association between the clinical findings and the composite outcome; and iv) use multivariable analysis to derive a highly sensitive clinical decision rule to guide triage decisions.</p> <p>Discussion</p> <p>The study will derive a highly sensitive clinical decision rule to identify low risk patients safe for early discharge. This will improve patient care, lower healthcare costs, and enhance flow in our busy and overcrowded emergency departments.</p

    Stakeholder Relationships and Social Welfare: A Behavioral Theory of Contributions to Joint Value Creation

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    Firms play a crucial role in furthering social welfare through their ability to foster stakeholders’ contributions to joint value creation, i.e., value creation that involves a public-good dilemma due to high task and outcome interdependence - leading to what economists have labeled the ‘team production problem’. We build on relational models theory to examine how individual stakeholders’ contributions to joint value creation are shaped by stakeholders’ mental representations of their relationships with the other participants in value creation, and how these mental representations are affected by the perceived behavior of the firm. Stakeholder theory typically contrasts a broadly-defined ‘relational’ approach to stakeholder management with a ‘transactional’ approach based on the price mechanism - and has argued that the former is more likely to contribute to social welfare than the latter. Our theory supports this prediction for joint value creation, but also implies that the dichotomy on which it is based is too coarse-grained: there are three distinct ways to trigger higher contributions to joint value creation than through a ‘transactional’ approach. Our theory also helps explain the tendency for firms and their stakeholders to converge on ‘transactional’ relationships, despite their relative inefficiency in the context of joint value creation

    Consumer-Based Leisure Constraint for Online Gaming

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    [[abstract]]The purpose of this study is to develop a multidimensional measure of consumer-based leisure constraint for online game play and to assess its psychometric properties. An empirical model of player constraint in online games provides the foundation to understanding and assessing how players differ from one another (such as high gamers/low gamers and high gamers/non-gamers) and how constraints on play relate to frequency of use. In the current study, an exploratory factor analysis was used to extract the common factors, and confirmatory factor analysis was used to create an empirical model of players' perception of constraint and to reveal its underlying structure. The analysis revealed six dimensions of constraint. The relationship between perception of constraint and frequency of use is also presented.[[notice]]補正完畢[[incitationindex]]SSCI[[booktype]]電子版[[booktype]]紙
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