scholarly journals Aerodynamic Contrails: Phenomenology and Flow Physics

2009 ◽  
Vol 66 (2) ◽  
pp. 217-226 ◽  
Author(s):  
K. Gierens ◽  
B. Kärcher ◽  
H. Mannstein ◽  
B. Mayer
Keyword(s):  
Ambient Atmosphere ◽  
Substantial Fraction ◽  
Upper Troposphere ◽  
Flow Physics ◽  
Aircraft Wings ◽  
Study Results ◽  
Adiabatic Cooling ◽  
Long Time ◽  
Formation Conditions

Abstract Aerodynamic contrails have been recognized for a long time although they appear sporadically. Usually one observes them under humid conditions near the ground, where they are short-lived phenomena. Aerodynamic contrails appear also at cruise levels where they may persist when the ambient atmosphere is ice-supersaturated. The present paper presents a theoretical investigation of aerodynamic contrails in the upper troposphere. The required flow physics are explained and applied to a case study. Results show that the flow over aircraft wings leads to large variations of pressure and temperature. Average pressure differences between the upper and lower sides of a wing are on the order of 50 hPa, which is a quite substantial fraction of cruise-level atmospheric pressures. Adiabatic cooling exceeds 20 K about 2 m above the wing in a case study shown here. Accordingly, extremely high supersaturations (exceeding 1000%) occur for a fraction of a second. The potential consequences for the ice microphysics are discussed. Because aerodynamic contrails are independent of the formation conditions of jet contrails, they form an additional class of contrails that might be complementary because they form predominantly in layers that are too warm for jet contrail formation.

scholarly journals Case study on the living standard of rice famers in An Giang province in the period of 2005-2014

2017 ◽  
Vol 1 (X1) ◽  
pp. 55-66
Author(s):  
Tran Gia Pham
Keyword(s):  
Living Standards ◽  
Living Standard ◽  
Rice Farming ◽  
Social Survey ◽  
Rice Farmers ◽  
Negative Change ◽  
Study Results ◽  
Long Time ◽  
Farming Households

For a more comprehensive look at the life of rice farmers in the context of environmental change, research on the change of the living standards of rice farming households in the period of 2005-2014 is done. In this study, social survey is utilized with sample size of 46 rice farming households in 6 districts in An Giang province (7-8 households/district on average) with the tool for data collection and analyzing having been the chart of selfevaluation of rice farmers on their living standards in the last 10 years. The study results showed that rice farming livelihood improves the life of farmers. However, if considered it during a long time, the living standard of the majority of rice farming households did not increase. Rice production is a kind of livelihood related to risks caused by negative change of the natural environment and the rice market's volatility. To adapt with the change of environment and to maintain the living standard, the rice farmers have implemented such solutions as livelihood diversification, plant transformation, increase of the cultivated areas and of investment in education for their children. Together with the goal of ensuring food security and enhancing rice exports, it is necessary to ensure profit, living standards of rice farmers, to strengthen their resources adapting to climate change, and to link the production with the market and international integration.

scholarly journals Case study on the living standard of rice famers in An Giang province in the period of 2005-2014

2017 ◽  
Vol 1 (X1) ◽  
pp. 55-66
Author(s):  
Tran Gia Pham
Keyword(s):  
Living Standards ◽  
Living Standard ◽  
Rice Farming ◽  
Social Survey ◽  
Rice Farmers ◽  
Negative Change ◽  
Study Results ◽  
Long Time ◽  
Farming Households

For a more comprehensive look at the life of rice farmers in the context of environmental change, research on the change of the living standards of rice farming households in the period of 2005-2014 is done. In this study, social survey is utilized with sample size of 46 rice farming households in 6 districts in An Giang province (7-8 households/district on average) with the tool for data collection and analyzing having been the chart of selfevaluation of rice farmers on their living standards in the last 10 years. The study results showed that rice farming livelihood improves the life of farmers. However, if considered it during a long time, the living standard of the majority of rice farming households did not increase. Rice production is a kind of livelihood related to risks caused by negative change of the natural environment and the rice market's volatility. To adapt with the change of environment and to maintain the living standard, the rice farmers have implemented such solutions as livelihood diversification, plant transformation, increase of the cultivated areas and of investment in education for their children. Together with the goal of ensuring food security and enhancing rice exports, it is necessary to ensure profit, living standards of rice farmers, to strengthen their resources adapting to climate change, and to link the production with the market and international integration.

PROCESSING AND IMAGING OF MARINE SEISMIC DATA FROM THE JEQUITINHONHA BASIN (BAHIA, BRAZIL)

2016 ◽  
Vol 33 (3) ◽  
Author(s):  
Lourenildo W.B. Leite ◽  
J. Mann ◽  
Wildney W.S. Vieira
Keyword(s):  
Seismic Data ◽  
Sedimentary Basins ◽  
Study Results ◽  
Marine Seismic ◽  
Present Case Study

ABSTRACT. The present case study results from a consistent processing and imaging of marine seismic data from a set collected over sedimentary basins of the East Brazilian Atlantic. Our general aim is... RESUMO. O presente artigo resulta de um processamento e imageamento consistentes de dados sísmicos marinhos de levantamento realizado em bacias sedimentares do Atlântico do Nordeste...

come_NET

2018 ◽  
Author(s):  
Konstantin Aal ◽  
Anne Weibert ◽  
Kai Schubert ◽  
Mary-Ann Sprenger ◽  
Thomas Von Rekowski
Keyword(s):  
Social Media ◽  
Design Process ◽  
Participatory Design ◽  
Controlled Environment ◽  
Design And Implementation ◽  
Neighborhood Contexts ◽  
Study Results ◽  
Computer Club ◽  
Close Cooperation

The case study presented in this chapter discusses the design and implementation of an online platform, “come_NET,” in the context of intercultural computer clubs in Germany. This tool was built in close cooperation with the children and adult computer club participants. It was designed to foster the sharing of ideas and experiences across distances, support collaboration, and make skills and expertise accessible to others in the local neighborhood contexts. In particular, the participatory-design process involving the children in the computer clubs fostered a profound understanding of the platform structure and functionalities. The study results show how younger children in particular were able to benefit, as the closed nature of the platform enabled them to gather experience as users of social media, but in a safe and controlled environment.

scholarly journals Optimizing the Environmental and Economic Sustainability of Remote Community Infrastructure

2020 ◽  
Vol 12 (6) ◽  
pp. 2208 ◽  
Author(s):  
Jamie E. Filer ◽  
Justin D. Delorit ◽  
Andrew J. Hoisington ◽  
Steven J. Schuldt
Keyword(s):  
Environmental Impacts ◽  
Sustainability Assessment ◽  
Model Performance ◽  
Assessment Model ◽  
Remote Communities ◽  
Remote Community ◽  
Rural Villages ◽  
Sustainable Technologies ◽  
Study Results

Remote communities such as rural villages, post-disaster housing camps, and military forward operating bases are often located in remote and hostile areas with limited or no access to established infrastructure grids. Operating these communities with conventional assets requires constant resupply, which yields a significant logistical burden, creates negative environmental impacts, and increases costs. For example, a 2000-member isolated village in northern Canada relying on diesel generators required 8.6 million USD of fuel per year and emitted 8500 tons of carbon dioxide. Remote community planners can mitigate these negative impacts by selecting sustainable technologies that minimize resource consumption and emissions. However, the alternatives often come at a higher procurement cost and mobilization requirement. To assist planners with this challenging task, this paper presents the development of a novel infrastructure sustainability assessment model capable of generating optimal tradeoffs between minimizing environmental impacts and minimizing life-cycle costs over the community’s anticipated lifespan. Model performance was evaluated using a case study of a hypothetical 500-person remote military base with 864 feasible infrastructure portfolios and 48 procedural portfolios. The case study results demonstrated the model’s novel capability to assist planners in identifying optimal combinations of infrastructure alternatives that minimize negative sustainability impacts, leading to remote communities that are more self-sufficient with reduced emissions and costs.

scholarly journals Seaports during the COVID-19 Pandemic: The Terminal Operators’ Tactical Responses to Disruptions in Maritime Supply Chains

Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4339
Author(s):  
Marta Mańkowska ◽  
Michał Pluciński ◽  
Izabela Kotowska ◽  
Ludmiła Filina-Dawidowicz
Keyword(s):  
Supply Chains ◽  
Global Economy ◽  
Research Study ◽  
Inductive Reasoning ◽  
Main Function ◽  
The Sustainable Development ◽  
Study Results ◽  
Multiple Case ◽  
Tactical Decisions

The world-wide crisis caused by the Coronavirus disease 2019 (COVID-19) pandemic had a significant impact on the global economy functioning and the sustainable development of supply chains. The changes also affected seaports being the key links of maritime supply chains. The purpose of the research study described in this article was to identify the sources and kinds of disruptions observed in various maritime supply chains as a result of the COVID-19 pandemic and their impact on the operations of various types of seaport terminals, namely those serving bulk (universal, specialised) and general cargoes (universal, specialised). An additional purpose was to identify the dependencies between the type of terminal and its main function, and the tactical decisions adopted by the particular terminals. The research was carried out using the multiple-case study method. The study covered some selected port terminals functioning in Polish seaports (Gdańsk, Szczecin, Świnoujście), applying direct, semi-structured in-depth interviews. The analysis of the results was carried out using the inductive reasoning method. The research study has shown that as a result of the COVID-19 pandemic some maritime supply chains ceased to exist, some of them were operating with decreased cargo volumes, while in other cases the transshipment volumes actually rose during the pandemic. Among terminal operators’ tactical responses to disruptions in maritime supply chains, there were pro-active and adaptive measures. Pro-active (offensive) measures included actions taken by an enterprise in order to engage in new maritime supply chains, and even participating in establishing new maritime chains in response to limitations caused by the pandemic. Adaptive (defensive) measures covered actions taken by the port terminals as a consequence of changes in the existing maritime supply chains, caused by the pandemic in the port’s foreland or hinterland. The research study results revealed that the terminals extent of engagement and tactical decisions related to the pandemic were depended on the type of terminal (universal or specialised) and its main function played within a supply chain.

scholarly journals A Holistic Framework for Evaluating Adaptation Approaches to Coastal Hazards and Sea Level Rise: A Case Study from Imperial Beach, California

Water ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1324
Author(s):  
David Revell ◽  
Phil King ◽  
Jeff Giliam ◽  
Juliano Calil ◽  
Sarah Jenkins ◽  
...  
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Public Trust ◽  
Adaptation Strategy ◽  
Public Benefits ◽  
Study Results ◽  
Local Risk ◽  
Over Time

Sea level rise increases community risks from erosion, wave flooding, and tides. Current management typically protects existing development and infrastructure with coastal armoring. These practices ignore long-term impacts to public trust coastal recreation and natural ecosystems. This adaptation framework models physical responses to the public beach and private upland for each adaptation strategy over time, linking physical changes in widths to damages, economic costs, and benefits from beach recreation and nature using low-lying Imperial Beach, California, as a case study. Available coastal hazard models identified community vulnerabilities, and local risk communication engagement prioritized five adaptation approaches—armoring, nourishment, living shorelines, groins, and managed retreat. This framework innovates using replacement cost as a proxy for ecosystem services normally not valued and examines a managed retreat policy approach using a public buyout and rent-back option. Specific methods and economic values used in the analysis need more research and innovation, but the framework provides a scalable methodology to guide coastal adaptation planning everywhere. Case study results suggest that coastal armoring provides the least public benefits over time. Living shoreline approaches show greater public benefits, while managed retreat, implemented sooner, provides the best long-term adaptation strategy to protect community identity and public trust resources.

scholarly journals Using Design Thinking Principles to Improve Outpatients’ Experiences in Hospital Pharmacies: A Case Study of Two Hospitals in Asir Region, Saudi Arabia

Healthcare ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 854
Author(s):  
Dalia Almaghaslah ◽  
Abdulrhman Alsayari ◽  
Saleh Ali Alyahya ◽  
Rana Alshehri ◽  
Khawlah Alqadi ◽  
...  
Keyword(s):  
Saudi Arabia ◽  
Problem Solving ◽  
Management System ◽  
Design Thinking ◽  
Queue Management ◽  
End User ◽  
Study Results ◽  
Hospital Pharmacies ◽  
Asir Region

Introduction: Design thinking, an innovative problem-solving approach, has gained wide popularity in healthcare disciplines. The aim of this work is to improve outpatients’ experiences in hospital pharmacies in two hospitals in Asir region, Saudi Arabia. Methods: The design thinking approach, adopted from Stanford University’s D-School, was used in this study. Results: Several problems were identified: lack of comfortable environment in the pharmacies’ waiting area, lack of a queue management system, and workflow inefficiencies related to ordering and supplies of medicines. A prototype was proposed to overcome these challenges. Discussion and Conclusion: The design thinking approach helped in identifying end-user (patients visiting outpatient pharmacies) values and desires and provided an understanding of their struggles. It also proposed tailored solutions that could improve patients’ experiences while using the services of the outpatient pharmacies.

scholarly journals Analysis of Dangerous Sea States in the Northwestern Mediterranean Area

2021 ◽  
Vol 9 (4) ◽  
pp. 422
Author(s):  
Alessio Innocenti ◽  
Miguel Onorato ◽  
Carlo Brandini
Keyword(s):  
Extreme Events ◽  
Mediterranean Area ◽  
Rayleigh Distribution ◽  
Surface Elevation ◽  
Wave Steepness ◽  
Sea Waves ◽  
Operational Forecasts ◽  
Long Time ◽  
Simulated Field

Extreme sea waves, although rare, can be notably dangerous when associated with energetic sea states and can generate risks for the navigation. In the last few years, they have been the object of extensive research from the scientific community that helped with understanding the main physical aspects; however, the estimate of extreme waves probability in operational forecasts is still debated. In this study, we analyzed a number of sea-states that occurred in a precise area of the Mediterranean sea, near the location of a reported accident, with the objective of relating the probability of extreme events with different sea state conditions. For this purpose, we performed phase-resolving simulations of wave spectra obtained from a WaveWatch III hindcast, using a Higher Order Spectral Method. We produced statistics of the sea-surface elevation field, calculating crest distributions and the probability of extreme events from the analysis of a long time-series of the surface elevation. We found a good matching between the distributions of the numerically simulated field and theory, namely Tayfun second- and third- order ones, in contrast with a significant underestimate given by the Rayleigh distribution. We then related spectral quantities like angular spreading and wave steepness to the probability of occurrence of extreme events finding an enhanced probability for high mean steepness seas and narrow spectra, in accordance with literature results, finding also that the case study of the reported accident was not amongst the most dangerous. Finally, we related the skewness and kurtosis of the surface elevation to the wave steepness to explain the discrepancy between theoretical and numerical distributions.

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