Assessing the Impact of Aviation System Performance by Using Airline Cost Functions

2000 ◽  
Vol 1703 (1) ◽  
pp. 16-23 ◽  
Author(s):  
Mark Hansen ◽  
David Gillen ◽  
Reza Djafarian-Tehrani
Keyword(s):  
Performance Metrics ◽  
Factor Model ◽  
Cost Savings ◽  
Cost Functions ◽  
Average Delay ◽  
Multifactor Models ◽  
Important Benefit ◽  
Domestic Airlines ◽  
And Performance ◽  
The Impact

The manner in which changes in the performance of the U.S. National Airspace System (NAS) affect carrier costs is examined. The methodology includes estimation of airline cost functions that contain NAS performance metrics as arguments, using quarterly data for 10 U.S. domestic airlines. The primary interest is in the impact of delay on cost performance, and performance metrics that vary by airline and quarter are developed. The potentially large number of metrics are reduced by applying factor analysis to seven underlying variables, including average delay, delay variance, and the proportion of flights that are cancelled. The analysis reveals that variations in the seven variables can be adequately captured by three or fewer factors. The three factors used correspond to “delay,” “variability,” and “disruption,” the last two of which are merged into a single “irregularity” factor in the two-factor model. When used as arguments in an airline cost function, the “disruption” factor is found to be a significant contributor to airline costs in the three-factor model, as is the “irregularity” factor in the two-factor model. No significant effect is found for the delay factor in the multifactor models. These results challenge the prevailing assumption that delay reduction is the most important benefit from investments in NAS capital and operations rules. The carrier cost savings that would result from improved NAS performance levels are estimated, and these are compared with previously published estimates.

scholarly journals Moving towards a reliable HIV incidence test – current status, resources available, future directions and challenges ahead

2016 ◽  
Vol 145 (5) ◽  
pp. 925-941 ◽  
Author(s):  
G. MURPHY ◽  
C. D. PILCHER ◽  
S. M. KEATING ◽  
R. KASSANJEE ◽  
S. N. FACENTE ◽  
...  
Keyword(s):  
Performance Metrics ◽  
Critical Path ◽  
Population Level ◽  
Current Status ◽  
Hiv Incidence ◽  
Recent Infection ◽  
Novel Approach ◽  
Product Profile ◽  
And Performance ◽  
The Impact

SUMMARYIn 2011 the Incidence Assay Critical Path Working Group reviewed the current state of HIV incidence assays and helped to determine a critical path to the introduction of an HIV incidence assay. At that time the Consortium for Evaluation and Performance of HIV Incidence Assays (CEPHIA) was formed to spur progress and raise standards among assay developers, scientists and laboratories involved in HIV incidence measurement and to structure and conduct a direct independent comparative evaluation of the performance of 10 existing HIV incidence assays, to be considered singly and in combinations as recent infection test algorithms. In this paper we report on a new framework for HIV incidence assay evaluation that has emerged from this effort over the past 5 years, which includes a preliminary target product profile for an incidence assay, a consensus around key performance metrics along with analytical tools and deployment of a standardized approach for incidence assay evaluation. The specimen panels for this evaluation have been collected in large volumes, characterized using a novel approach for infection dating rules and assembled into panels designed to assess the impact of important sources of measurement error with incidence assays such as viral subtype, elite host control of viraemia and antiretroviral treatment. We present the specific rationale for several of these innovations, and discuss important resources for assay developers and researchers that have recently become available. Finally, we summarize the key remaining steps on the path to development and implementation of reliable assays for monitoring HIV incidence at a population level.

New York’s Medicare Marketplace: Examining New York’s Medicare Advantage Plan Landscape in Light of Payment Reform

2013 ◽  
Vol 14 (3) ◽  
pp. 187-196 ◽  
Keyword(s):  
New York ◽  
Performance Metrics ◽  
New York State ◽  
Cost Savings ◽  
Medicare Advantage ◽  
Medicare Beneficiaries ◽  
Payment Reform ◽  
Cost Structures ◽  
Sound Policy ◽  
And Performance

The Patient Protection and Affordable Care Act (ACA) provided for cost savings in the Medicare program, in part to underwrite coverage expansion to Medicare beneficiaries, to finance new coverage for those not eligible for Medicare, and to strengthen Medicare’s financial outlook. One cost-saving measure, a reformulation and reduction in payments to private health insurance plans that provide Medicare benefits through the Medicare Advantage (MA) program, had a sound policy basis but was criticized, particularly by opponents of the ACA, as a measure that would lead to increased costs, reductions in benefits, and diminished plan choices to Medicare beneficiaries enrolled in MA plans. Despite dire predictions to this effect, a review of a sample of MA plan offerings in New York State in 2012 shows that Medicare beneficiaries enrolled in such plans did not experience significant benefit reductions or increased costs. While the number of plan offerings decreased, the reduction was mostly caused by the elimination of duplicative plan choices in 2011. Although the MA plan executives we interviewed indicated that further reductions in plan reimbursement in future years—tempered by potential bonus payments for meeting quality and performance metrics—could impact plan costs and benefits, they believed plans will employ a number of strategies to remain in the market and maintain beneficiary benefits and cost structures. However, government regulators and consumer advocates will need to examine MA plan offerings in the coming years to determine the effect of plan reaction to the ACA payments on beneficiaries’ costs for coverage and access to care.

Wind Catcher Technology: The Impact of Tower Cross Section and Turbine on Wind Power Harnessing

2019 ◽  
Author(s):  
Jonathan C. Corbett ◽  
Navid Goudarzi ◽  
Mohammadamin Sheikhshahrokhdehkordi
Keyword(s):  
Wind Power ◽  
Wind Turbines ◽  
Cross Sections ◽  
Natural Ventilation ◽  
Performance Metrics ◽  
Urban Environments ◽  
Ducted Turbine ◽  
And Performance ◽  
Turbine Design ◽  
The Impact

Abstract This research explores utilizing distributed wind turbines in the built environment computationally. The targeted wind turbine design is an unconventional ducted turbine, called Wind Tower technology that its operation and performance metrics have been studied in earlier works in the team. Wind Tower is an established architectural technology that operates by catching wind and directing it into buildings, providing natural ventilation to support HVAC systems, and thus reducing cooling costs in urban environments. Wind power has long struggled to meet expectations in built (urban) environments. By combining wind towers at different cross sections with wind turbines, one might develop a device which provides natural ventilation and produces power in spite of a hostile wind environment. The preliminary results suggest that the maximum potential for a wind tower-turbine combination appears to be 700-1.46 kW under idealized conditions with a 4 m/s site dominant wind speed. This suggests that wind towers might be viable for power harvesting in both remote and grid connected regions. Further analysis suggested that additional turbine performance enhancements are needed to bring the turbine real power production closer to that ideal.

Measuring the Effects of Information Systems on the Performance of Operating Rooms (OR)

2010 ◽  
Vol 5 (1) ◽  
pp. 16-36
Author(s):  
Elad Harison ◽  
Egon Berghout
Keyword(s):  
Information Systems ◽  
Quantitative Methods ◽  
Cost Savings ◽  
Operating Rooms ◽  
Performance Model ◽  
Qualitative And Quantitative Methods ◽  
Positive Effects ◽  
Personnel Planning ◽  
And Performance ◽  
The Impact

The paper applies various qualitative and quantitative methods to measure the influence of information technology on the performance of operating rooms (ORs). It provides a comprehensive set of indicators to evaluate the impact of IT on the quality, efficiency and performance of ORs. This set of indicators was further enriched by conducting interviews with hospital professionals. The result is a new set of performance indicators, divided into five major categories: productivity, efficiency, quality, cost savings and employee satisfaction. This set of indicators serves as a basis for a weighed performance model that can be applied as a useful tool for selecting new OR information systems. Additionally, the model can be used for improving existing applications. The research identifies time registration, integration with the medical and financial systems of the hospital and production of activity queries and reports as the most common functions of ORs systems. However, despite their potential to contribute to productivity, efficiency and quality of ORs, automatic conflict recognition, material and personnel planning are less frequently applied by hospitals. Finally, the paper highlights the links between efficient use of OR systems, larger volumes of operations and higher occupation rates, and assists in identifying positive effects of systems used in ORs on their performance.

The impact of modelling decisions in hydrological modelling

2021 ◽  
Author(s):  
Janneke Remmers ◽  
Ryan Teuling ◽  
Lieke Melsen
Keyword(s):  
Scientific Reasoning ◽  
Performance Metrics ◽  
Expert Knowledge ◽  
Modelling Framework ◽  
Modelling Environment ◽  
And Performance ◽  
Definition Of ◽  
The Impact ◽  
Modular Modelling ◽  
Modelling Process

<p>Scientific hydrological modellers make multiple decisions during the modelling process, e.g. related to the calibration period and performance metrics. These decisions affect the model results differently. Modelling decisions can refer to several steps in the modelling process. In this project, modelling decisions refer to the decisions made during the whole modelling process, not just the definition of the model structure. Each model output is a hypothesis of the reality; it is an interpretation of the real system underpinned by scientific reasoning and/or expert knowledge. Currently, there is a lack of knowledge and understanding about which modelling decisions are taken and why they are taken. Consequently, the influence of modelling decisions is unknown. Quantifying this influence, which is done in this study, can raise awareness among scientists. This study is based on analysis of interviews with scientific hydrological modellers, thus taking actual practices into account. Different modelling decisions were identified from the interviews, which are subsequently implemented and evaluated in a controlled modelling environment, in our case the modular modelling framework Raven. The variation in the results is analysed to determine which decisions affect the results and how they affect the results. This study pinpoints what aspects are important to consider in studying modelling decisions, and can be an incentive to clarify and improve modelling procedures.</p>

scholarly journals Delivering on Purpose

2021 ◽  
pp. 113-129
Author(s):  
Yassine El Ouarzazi
Keyword(s):  
Performance Metrics ◽  
Step Process ◽  
Baseline Performance ◽  
Self Interest ◽  
The Creation ◽  
And Performance ◽  
The Impact ◽  
Pain Points

Chapter 8 describes the process of ecosystem orchestration in more detail. It sets out an eight-step process around: (a) establishing a purpose, (b) designing metrics that measure the purpose, (c) identifying the relevant stakeholders, (d) mapping their objectives, capabilities, relationships, and pain points (i.e. problems), (e) selecting the pain points in the ecosystem that the organization should address, (f) measuring the baseline performance metrics before the intervention, (g) identifying, testing, and implementing the interventions to address the pain points, and (h) measuring the impact of the interventions on purpose and performance. The chapter emphasizes that the process of ecosystem orchestration involves the company placing the interests of the ecosystem and the ecosystem’s purpose against the company’s own self-interest at the centre of its own purpose. In so doing, the company should embrace the creation of mutuality of benefits not for enlightened self-interest but on a commitment to delivering the ecosystem purpose.

scholarly journals A Scoping Review: The Impact of Housing Systems and Environmental Features on Beef Cattle Welfare

Animals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 565 ◽  
Author(s):  
Rachel M. Park ◽  
Margaret Foster ◽  
Courtney L. Daigle
Keyword(s):  
Beef Cattle ◽  
Scoping Review ◽  
Environmental Enrichment ◽  
Performance Metrics ◽  
Feedlot Cattle ◽  
Housing Systems ◽  
Advantages And Disadvantages ◽  
Environmental Features ◽  
And Performance ◽  
The Impact

Housing systems and environmental features can influence beef cattle welfare. To date, little information has been synthesized on this topic. The aim of this scoping review was to examine the relationship between housing and welfare status, so that beef cattle producers and animal scientists can make informed decisions regarding how their housing choices could impact beef cattle welfare. Housing features were categorized by floor type, space allowance and shade availability, as well as the inclusion of enrichment devices or ventilation features. Evaluation of space allowances across feedlot environments determined behavioral and production benefits when cattle were housed between 2.5 m2 to 3.0 m2 per animal. Over 19 different flooring types were investigated and across flooring types; straw flooring was viewed most favorably from a behavioral, production and hygiene standpoint. Veal calves experience enhanced welfare (e.g., improved behavioral, physiological, and performance metrics) when group housed. There is evidence that the implementation of progressive housing modifications (e.g., shade, environmental enrichment) could promote the behavioral welfare of feedlot cattle. This review presents the advantages and disadvantages of specific housing features on the welfare of beef cattle.

scholarly journals The impact of distraction minimization on endoscopic mentoring and performance

2020 ◽  
Vol 08 (12) ◽  
pp. E1804-E1810
Author(s):  
Sean C. Rice ◽  
James C. Slaughter ◽  
Walter Smalley ◽  
Keith L. Obstein
Keyword(s):  
Performance Metrics ◽  
Polyp Detection ◽  
Cecal Intubation ◽  
Withdrawal Time ◽  
Total Procedure Time ◽  
Polyp Detection Rate ◽  
Active Attention ◽  
And Performance ◽  
Mean Differences ◽  
The Impact

Abstract Background and study aims Endoscopic mentoring requires active attention by the preceptor. Unfortunately, sources of distraction are abundant during endoscopic precepting. The impact of distraction minimization on endoscopic mentoring and performance is unknown. Methods Fellow and attending preceptors were paired and randomized in a prospective crossover design to perform esophagogastroduodenoscopy (EGD) and/or colonoscopy in either a “distraction minimization” (DM) or a “standard” (S) room. Cell phones, pagers, music, and computers were not permitted in DM rooms. S rooms operated under typical conditions. Fellows and attendings then completed a survey. The primary outcome was fellow satisfaction with mentoring experience (visual analogue scale: 0 = min,100 = max). Additional fellow outcomes included satisfaction of attending attentiveness, identifying landmarks, communication, and distractedness; attending outcomes included satisfaction with mentoring, attentiveness, communication, and distractedness. Endoscopic performance measures included completion of EGD, cecal intubation rate, cecal intubation time, withdrawal time, total procedure time, attending assistance, and polyp detection rate. A paired t-test was used to compare mean differences (MD) between rooms; significance set at P < 0.05. Results Eight fellows and seven attendings completed 164 procedures. Despite a trend toward less distraction between rooms (DM = 12.5 v. S = 18.3, MD =  4.1, P = 0.17), there was no difference in fellow satisfaction with training/mentoring (DM = 93, S = 93, MD = –0.04, P = 0.97), attentiveness (DM = 95, S = 92, MD = 0.86, P = 0.77), identifying pathology/landmarks (DM = 94, S = 94, MD = –1.72, P = 0.56), or communication (DM = 95, S = 95,MD = 1.0, P = 0.37). Similarly, there was no difference between rooms for any attending outcome measures or performance metrics. Conclusions DM did not improve perceived quality of endoscopic mentoring or performance for fellows or attendings; however, reduced distraction may improve attending engagement/availability.

The Impact of Temperature and Concentration on SC2 Cost and Performance in a production Environment

1997 ◽  
Vol 477 ◽  
Author(s):  
D. J. Riley ◽  
J. S. Glick ◽  
V. Parks ◽  
G. Matamis
Keyword(s):  
Cost Savings ◽  
Additional Benefit ◽  
Silicon Surfaces ◽  
Production Environment ◽  
Potential Production ◽  
Considerable Cost ◽  
Thermal Oxide ◽  
Peroxide Decomposition ◽  
And Performance ◽  
The Impact

ABSTRACTRecent studies have shown that extremely dilute HCl mixtures can offer considerable cost savings and improved particle performance relative to traditional SC2 formulations. This work indicates, however, that extreme levels of dilution are not necessary to secure many of the benefits suggested for dilute HCI. Significant benefit can be attained by pursuing moderate concentration and temperature alterations. In this study, an intermediate dilution and temperature reduction are evaluated to assess potential production advantage. Comparison of a 1:1:20 formulation at 60 C is made to a more traditional 1:1:6 mixture at 85 C. The impact of the chemistry and temperature alteration on peroxide decomposition rate is shown to be dramatic. While initial pour-up ratios suggest that the dilute recipe could require 1/3 as much peroxide as the traditional chemistry, chemical savings are significantly more dramatic due to the ability of the solution to maintain concentration over time. An additional benefit associated with the alternative pour-up is a marked reduction in particle levels on silicon surfaces; particle levels on thermal oxide wafers have not shown the same trend. VPD-ICPMS measurements are used in this study to illustrate that the recipe change results in comparable metallic removal efficiency.

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