scholarly journals The Impact of Selected Atmospheric Conditions on the Process of Abrasive Wear of CFRP

Materials ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 3965 ◽  
Author(s):  
Aneta Krzyzak ◽  
Damian Racinowski ◽  
Robert Szczepaniak ◽  
Mateusz Mucha ◽  
Ewelina Kosicka

The aim of this study was to examine the impact of weathering and thermal shocks on the abrasive wear of epoxy resin composites reinforced with carbon fabric that are commonly used in aviation. The composite was exposed to degradation in an apparatus simulating weathering and thermal shocks and then subjected to an abrasion process, with and without the presence of water. The abrasive wear was controlled by checking the weight loss as well as by visual inspection. The research findings indicated a significant effect of the presence of water in the process of friction upon the deterioration of composite resistance to abrasion with regard to dry friction. The long-term impact of rapid cyclic temperature changes (temperature difference: from −56.5 °C to +60 °C) and a combined effect of UV-A (0.83 W/m2), along with condensation of vapor and an increased ambient temperature (above 50 °C), influenced an improvement in resistance to abrasive wear. The environment of thermal shocks diminished abrasive wear to a much smaller extent than after exploitation in an environment of weathering but both environments contributed to the degradation of the surface layer. Additionally, the environment with UV-A radiation resulted in exposure of the composite reinforcement already after four months of environmental impact.

2021 ◽  
Vol 11 ◽  
pp. 43-63
Author(s):  
Prakash Gautam

The hospitality and tourism sector is considered the backbone for economicgrowth, especially in developing countries. However, this thriving sector is particularly vulnerable to naturaland human-made disasters. This study assesses the impact of the COVID-19 (coronavirus disease-2019) pandemic in India’s hospitality and tourism sector by addressing essential aspects such as current conditions and challenges as well as future perspectives. The secondary research methodology has been applied for the research. For data collection, the secondary data has been collected through literature, journal articles, government documents, etc. The research findings show that COVID-19 in India has significantly affected the hospitality and tourism sector. Global and domestic tourists have canceled their programs to visit the natural, historical, religious, and cultural sites. The flight tickets and the hotel reservations have been canceled. A significant number of workers in the sector have lost their jobs. This pandemic has affected the economy of the country as well as the well-being of the individuals to a large extent. As the intensification of the COVID-19 is being thought to cause a long-term impact, this study could be relevant to the decision-makers in regards to the crucial task of reviving the sector.


Coronaviruses ◽  
2020 ◽  
Vol 01 ◽  
Author(s):  
Yam Nath Paudel ◽  
Efthalia Angelopoulou ◽  
Bhupendra Raj Giri ◽  
Christina Piperi ◽  
Iekhsan Othman ◽  
...  

: COVID-19 has emerged as a devastating pandemic of the century that the current generations have ever experienced. The COVID-19 pandemic has infected more than 12 million people around the globe and 0.5 million people have succumbed to death. Due to the lack of effective vaccines against the COVID-19, several nations throughout the globe has imposed a lock-down as a preventive measure to lower the spread of COVID-19 infection. As a result of lock-down most of the universities and research institutes has witnessed a long pause in basic science research ever. Much has been talked about the long-term impact of COVID-19 in economy, tourism, public health, small and large-scale business of several kind. However, the long-term implication of these research lab shutdown and its impact in the basic science research has not been much focused. Herein, we provide a perspective that portrays a common problem of all the basic science researchers throughout the globe and its long-term consequences.


2021 ◽  
pp. 089443932098413
Author(s):  
Carina Cornesse ◽  
Ines Schaurer

While online panels offer numerous advantages, they are often criticized for excluding the offline population. Therefore, some probability-based online panels have developed offline population inclusion strategies. Two dominant approaches prevail: providing internet equipment and offering an alternative survey participation mode. We investigate the impact of these approaches on two probability-based online panels in Germany: the German Internet Panel, which provides members of the offline population with internet equipment, and the GESIS Panel, which offers members of the offline population to participate via postal mail surveys. In addition, we explore the impact of offering an alternative mode only to non-internet users versus also offering the alternative mode to internet users who are unwilling to provide survey data online. Albeit lower recruitment and/or panel wave participation probabilities among offliners than onliners, we find that including the offline population has a positive long-term impact on sample accuracy in both panels. In the GESIS Panel, the positive impact is particularly strong when offering the alternative participation mode to non-internet users and internet users who are unwilling to provide survey data online.


2020 ◽  
Vol 20 (3) ◽  
pp. 317-351
Author(s):  
Scott Desposato ◽  
Gang Wang

AbstractDemocracy movements in authoritarian regimes usually fail and are repressed, but they may still affect attitudes and norms of participants and bystanders. We exploit several features of a student movement to test for enduring effects of social movements on democratic attitudes. College students were the core of the movement and had wide exposure to the ideas and activities of the movement, as well as the suppression of the movement. College-bound high school students had limited exposure to the movement and its activities. Time of college entry could in theory be manipulated and endogenous, so we also use birthdate as an exogenous instrument for enrollment year. Applying a fuzzy regression discontinuity, we test for the impact of exposure to the movement on long-term attitudes. We find significant attitudinal differences between those in college during the movement, and those who started college post-movement. These results are strongest for alumni of the four universities that were most connected to the movement.


2021 ◽  
pp. 003329412110051
Author(s):  
Rashmi Gupta ◽  
Jemima Jacob ◽  
Gaurav Bansal

Psychosocial stressors and social disadvantages contribute to inequalities in opportunities and outcomes. In the current paper, we use an epidemiological perspective and highlight the role stress plays on individuals by reviewing the outcomes of major stressors such as poverty and unemployment. We further analyzed the psychological and physical cost of these stressors and their long-term impact. We examined the role of universal basic income and closely looked at income experiments that were implemented in the past, in terms of their effectiveness in enhancing the community as well as individual outcomes and propose the UBI as a tool for alleviating the impact of these stressors. At a time when a major pandemic (e.g., COVID-19) threatens economic stability and health globally, we believe the UBI is relevant now, more than ever.


2015 ◽  
Vol 31 (2) ◽  
pp. 264-279 ◽  
Author(s):  
Anat Abramovich ◽  
Yahavit Loria

AbstractThe impact of an Education for Sustainability (EfS) course for science and technology junior high school teachers on the intentional and actual environmental behaviour of participants was studied by researching the EfS implementation of 13 science and technology teachers within their family, community, and work environment. The research was qualitative in nature, where science and technology teachers’ insights on the EfS course were determined by means of an open-ended questionnaire and intensive interviews. Results indicated that the course clearly influenced the vast majority of the participants, who claimed that their environmental awareness had increased and they were capable of acting responsibly. All participants acted in favour of the environment among family, community, and at work. Yet, 2 years later, implementation seemed to be undermined by various internal and external barriers, such as the unavailability of convenient resources, or resistance on the part of family. The study suggests that course designers must include reference to potential difficulties and barriers in order to circumvent future obstacles. In addition, the implementation of post-course support would encourage overcoming the gap between willingness to act and actual practice.


Author(s):  
Ali Kamyab ◽  
Steve Andrle ◽  
Dennis Kroeger ◽  
David S. Heyer

Many Minnesota counties are faced with the problem of high vehicle speeds through towns or resort areas that have significant pedestrian traffic. The impact of speed reduction strategies in high-pedestrian areas in rural counties of Minnesota was investigated. Speed data were collected at two selected study sites under their existing conditions ("no-treatment" or "before" condition) and after the proposed speed reduction strategies were installed. Second "after" data conditions were collected to study the short-term and long-term impact of the implemented strategies. The traffic-calming techniques employed at the Twin Lakes site consisted of removable pedestrian islands and pedestrian crossing signs. A dynamic variable message sign that sent a single-word message ("Slow") to motorists traveling over the speed limit was installed at the Bemidji site. The research study shows that the traffic-calming strategy deployed in Twin Lakes was effective in significantly reducing the mean speed and improving speed limit compliance in both the short term and long term. Despite proven effectiveness, the deployed speed reduction treatment in Bemidji Lake failed to lower the speed at the study site. The single-word message on the sign and the location of the sign, as well as a lack of initial enforcement, were the primary reasons for such failure.


2018 ◽  
Vol 39 (8) ◽  
pp. 1582-1610 ◽  
Author(s):  
NICK CADDICK ◽  
HELEN CULLEN ◽  
AMANDA CLARKE ◽  
MATT FOSSEY ◽  
MICHAEL HILL ◽  
...  

ABSTRACTThe impact of losing a limb in military service extends well beyond initial recovery and rehabilitation, with long-term consequences and challenges requiring health-care commitments across the lifecourse. This paper presents a systematic review of the current state of knowledge regarding the long-term impact of ageing and limb-loss in military veterans. Key databases were systematically searched including: ASSIA, CINAHL, Cochrane Library, Medline, Web of Science, PsycArticles/PsychInfo, ProQuest Psychology and ProQuest Sociology Journals, and SPORTSDiscus. Empirical studies which focused on the long-term impact of limb-loss and/or health-care requirements in veterans were included. The search process revealed 30 papers relevant for inclusion. These papers focused broadly on four themes: (a) long-term health outcomes, prosthetics use and quality of life; (b) long-term psycho-social adaptation and coping with limb-loss; (c) disability and identity; and (d) estimating the long-term costs of care and prosthetic provision. Findings present a compelling case for ensuring the long-term care needs and costs of rehabilitation for older limbless veterans are met. A dearth of information on the lived experience of limb-loss and the needs of veterans’ families calls for further research to address these important issues.


2020 ◽  
Vol 65 (4) ◽  
pp. 133-137 ◽  
Author(s):  
Khurram Shahzad Khan ◽  
Rona Keay ◽  
Morag McLellan ◽  
Sajid Mahmud

Background and aims COVID-19 pandemic has caused significant disruption in training which is even more pronounced in the surgical specialties. We aim to assess the impact of COVID-19 pandemic on core surgical training. Methods All core surgical and improving surgical trainees in West of Scotland region were invited to participate in an online voluntary anonymous survey via SurveyMonkey. Results 28 of 44 (63.6%) trainees responded, 15 (53.6%) were CT1/ST1. 14 (50.0%) working in teaching hospital and 15 (53.6%) working in general surgery. 20 (71.4%) felt that due to the pandemic they have less opportunity to operate as the primary surgeon. 21 (75.0%) have not attended any outpatient clinics. 8 (28.6%) did not have any form of access to the laparoscopic box-trainer. 20 (71.4%) felt their level of confidence in preforming surgical skills has been negatively impacted. 18 (64.3%) found it difficult to demonstrate progress in portfolio. 21 (75.0%) trainees have not attended any teaching. 10 (35.7%) trainees have been off-sick. 8 (28.6%) trainees have felt slightly or significantly more stressed. Conclusion COVID-19 pandemic has an unprecedented negative impact on all aspects of core surgical training. The long term impact on the current cohort of trainees is yet to be seen.


Economies ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 107
Author(s):  
Mirzosaid Sultonov

Russia’s international comportment and geostrategic moves, particularly the invasion of Ukraine and the annexation of Crimea in 2014, caused a substantial change in its international economic and political relations. In response to Russia’s invasion, the United States of America, the European Union, and their allies imposed a series of sanctions. In this study, by applying an exponential generalized autoregressive conditional heteroscedasticity model to daily logarithmic returns of the ruble exchange rate and the closing price index of the Russian Trading System, we analyze how the returns and volatility of the exchange rate and the stock price index responded to the sanctions and oil price changes. The estimation results show that the sanctions have a significant positive short-term impact on exchange rate returns. Economic sanctions have a significant negative long-term impact on the returns and variance of the exchange rate and a significant positive long-term impact on the returns of the stock price index. Financial sanctions have a positive/negative long-term impact on the returns of the exchange rate/stock price index and a positive long-term impact on the variance of the exchange rate and the stock price index. Corporate sanctions have a positive long-term impact on exchange rate returns.


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