scholarly journals Bond Strength Analysis of Repaired Concrete based on Polymerization of Glycoluril Formaldehyde

2021 ◽  
Author(s):  
Pothinathan SKM ◽  
◽  
Muthukannan M ◽  
Selvapalam N ◽  
S. Christopher Gnanaraj ◽  
...  
Keyword(s):  
Bond Strength ◽  
Surface Preparation ◽  
Interfacial Area ◽  
Correct Choice ◽  
Strength Analysis ◽  
Bonding Material ◽  
Different Types ◽  
Cement Mixture ◽  
The Impact ◽  
Slant Shear

Repairing old concrete include the correct choice of material and methodology adopted which may not affect the quality providing monolithic condition for old and new concrete. This study investigates two different parameters such as the impact as well as the optimum usage of new polymer glycoluril-formaldehyde as bonding material. Second one is about to understand the surface preparation for increased bonding strength at the interfacial area of old and new concrete. Five different types of surface textures are used to estimate the bond strength such as plane, lined, waved, grid and chipped. Glycoluril aids as a bonding material in both old and new concrete, and it is introduced at 0%, 1%, 2%, 3%, and 4% into the cement mixture. When the surface preparation creates a rough surface, it helps in repairing the concrete with the help of polymerization of glycoluril formaldehyde which promotes the enhancement of bond strength and slant shear. The bond strength of the specimens was measured by slant shear method in compression as well as tension for a period of 1, 2 and 4 weeks of new concrete. The results indicated that the highest bond strength was achieved in 3 percentage addition of glycoluril and grid patten substrate preparation.

scholarly journals Examining the Effect of Laser Radiation on the Repair of Dental Composite Restorations: A Systematic Review

2020 ◽  
Vol 12 (4) ◽  
pp. 142-147
Author(s):  
Loghman Rezaei-Soufi ◽  
Fatemeh Maddah ◽  
Younes Mohammadi
Keyword(s):  
Laser Radiation ◽  
Bond Strength ◽  
Selection Criteria ◽  
Web Of Science ◽  
Surface Preparation ◽  
Dental Composite ◽  
Laser Method ◽  
Composite Restorations ◽  
Significant Difference ◽  
The Impact

Background: This study aimed to determine the impact of laser radiation on the repair bond strength of dental composite restorations by gathering, assessing, and systematically reviewing previous articles referring to this issue. Methods: Several previous studies relevant to the objectives of this research were found in PubMed, Scopus, and Web of Science databases. All prior articles indexed in these databases according to the selected keywords until 2018 were gathered and assessed. Some article abstracts showed the necessary basic conditions for inclusion in the study. Therefore, the full texts of these relevant articles were further evaluated in terms of the study objectives. Results: A total of 300 relevant articles were obtained by searching the databases. Eight studies remained highly relevant after performing a title review, eliminating the duplicate articles, and implementing the selection criteria. The latest study was conducted in 2018. A statistically significant difference was observed between the impacts of laser and other methods in the seven of these final relevant studies. Of these articles, five indicated a better impact in the case of other methods, particularly the dental milling technique, and one study was related to the impacts of the laser method. Additionally, the Er,Cr: YSGG laser was considered the most adequate laser in these studies. Conclusions: According to the review of prior studies on the impact of laser radiation on the repair bond strength of composite restorations, Er: YAG and Er,Cr: YSGG lasers are advised for surface preparation of composites. However, surface preparation by adopting the milling technique remains the adequate choice for repairing composites.

The impact of surface preparation on the bond strength of repaired concrete by metakaolin containing concrete

2015 ◽  
Vol 80 ◽  
pp. 76-83 ◽  
Author(s):  
Reza Mirmoghtadaei ◽  
Masih Mohammadi ◽  
Nasibe Ashraf Samani ◽  
Seyedreza Mousavi
Keyword(s):  
Bond Strength ◽  
Surface Preparation ◽  
The Impact

Quota Women Are Threatening to Men

2017 ◽  
Vol 76 (3) ◽  
pp. 107-116 ◽  
Author(s):  
Klea Faniko ◽  
Till Burckhardt ◽  
Oriane Sarrasin ◽  
Fabio Lorenzi-Cioldi ◽  
Siri Øyslebø Sørensen ◽  
...  
Keyword(s):  
Decision Making ◽  
Organizational Performance ◽  
Gender Stereotypes ◽  
Perceived Threat ◽  
Preferential Treatment ◽  
Public Sector Employees ◽  
Different Types ◽  
Low Levels ◽  
Women In Decision Making ◽  
The Impact

Abstract. Two studies carried out among Albanian public-sector employees examined the impact of different types of affirmative action policies (AAPs) on (counter)stereotypical perceptions of women in decision-making positions. Study 1 (N = 178) revealed that participants – especially women – perceived women in decision-making positions as more masculine (i.e., agentic) than feminine (i.e., communal). Study 2 (N = 239) showed that different types of AA had different effects on the attribution of gender stereotypes to AAP beneficiaries: Women benefiting from a quota policy were perceived as being more communal than agentic, while those benefiting from weak preferential treatment were perceived as being more agentic than communal. Furthermore, we examined how the belief that AAPs threaten men’s access to decision-making positions influenced the attribution of these traits to AAP beneficiaries. The results showed that men who reported high levels of perceived threat, as compared to men who reported low levels of perceived threat, attributed more communal than agentic traits to the beneficiaries of quotas. These findings suggest that AAPs may have created a backlash against its beneficiaries by emphasizing gender-stereotypical or counterstereotypical traits. Thus, the framing of AAPs, for instance, as a matter of enhancing organizational performance, in the process of policy making and implementation, may be a crucial tool to countering potential backlash.

Situational Breakdowns

2019 ◽  
Author(s):  
Anne Nassauer
Keyword(s):  
United States ◽  
Large Scale ◽  
Contextual Factors ◽  
The United States ◽  
Social Outcomes ◽  
Dynamic Processes ◽  
Collective Decisions ◽  
Different Types ◽  
The Impact

This book provides an account of how and why routine interactions break down and how such situational breakdowns lead to protest violence and other types of surprising social outcomes. It takes a close-up look at the dynamic processes of how situations unfold and compares their role to that of motivations, strategies, and other contextual factors. The book discusses factors that can draw us into violent situations and describes how and why we make uncommon individual and collective decisions. Covering different types of surprise outcomes from protest marches and uprisings turning violent to robbers failing to rob a store at gunpoint, it shows how unfolding situations can override our motivations and strategies and how emotions and culture, as well as rational thinking, still play a part in these events. The first chapters study protest violence in Germany and the United States from 1960 until 2010, taking a detailed look at what happens between the start of a protest and the eruption of violence or its peaceful conclusion. They compare the impact of such dynamics to the role of police strategies and culture, protesters’ claims and violent motivations, the black bloc and agents provocateurs. The analysis shows how violence is triggered, what determines its intensity, and which measures can avoid its outbreak. The book explores whether we find similar situational patterns leading to surprising outcomes in other types of small- and large-scale events: uprisings turning violent, such as Ferguson in 2014 and Baltimore in 2015, and failed armed store robberies.

scholarly journals A global analysis of the impact of COVID-19 stay-at-home restrictions on crime

2021 ◽  
Author(s):  
Amy E. Nivette ◽  
Renee Zahnow ◽  
Raul Aguilar ◽  
Andri Ahven ◽  
Shai Amram ◽  
...  
Keyword(s):  
Public Space ◽  
Global Analysis ◽  
Sudden Change ◽  
Interrupted Time Series ◽  
Urban Crime ◽  
Substantial Variation ◽  
Different Types ◽  
Time Series Analyses ◽  
The Impact ◽  
At Home

AbstractThe stay-at-home restrictions to control the spread of COVID-19 led to unparalleled sudden change in daily life, but it is unclear how they affected urban crime globally. We collected data on daily counts of crime in 27 cities across 23 countries in the Americas, Europe, the Middle East and Asia. We conducted interrupted time series analyses to assess the impact of stay-at-home restrictions on different types of crime in each city. Our findings show that the stay-at-home policies were associated with a considerable drop in urban crime, but with substantial variation across cities and types of crime. Meta-regression results showed that more stringent restrictions over movement in public space were predictive of larger declines in crime.

Comprehensive Effects of Short-Term Rental Platforms Across Hotel Types in U.S. and International Destinations

2021 ◽  
pp. 193896552110335
Author(s):  
John W. O’Neill ◽  
Jihwan Yeon
Keyword(s):  
Service Providers ◽  
Comprehensive Analysis ◽  
Competitive Market ◽  
Substitution Effects ◽  
Short Term ◽  
Hotel Performance ◽  
The World ◽  
Different Types ◽  
Location Type ◽  
The Impact

In recent years, short-term rental platforms in the lodging sector, including Airbnb, VRBO, and HomeAway, have received extensive attention and emerged as potentially alternative suppliers of services traditionally provided by established commercial accommodation providers, that is, hotels. Short-term rentals have dramatically increased the available supply of rooms for visitors to multiple international destinations, potentially siphoning demand away from hotels to short-term rental businesses. In a competitive market, an increase in supply with constant demand would negatively influence incumbent service providers. In this article, we examine the substitution effects of short-term rental supply on hotel performance in different cities around the world. Specifically, we comprehensively investigate the substitution effects of short-term rental supply on hotel performance based on hotel class, location type, and region. Furthermore, we segment the short-term rental supply based on its types of accommodations, that is, shared rooms, private rooms, and entire homes, and both examine and quantify the differential effects of these types of short-term rentals on different types of hotels. This study offers a comprehensive analysis regarding the impact of multiple short-term rental platforms on hotel performance and offers both conceptual and practical insights regarding the nature and extent of the effects that were identified.

Double, triple or quadruple hits? Exploring the impact of cybercrime on victims in the Netherlands

2021 ◽  
pp. 026975802110106
Author(s):  
Raoul Notté ◽  
E.R. Leukfeldt ◽  
Marijke Malsch
Keyword(s):  
Public Opinion ◽  
Literature Review ◽  
The Netherlands ◽  
Public Discourse ◽  
Moral Judgments ◽  
Victim Blaming ◽  
High Prevalence ◽  
Different Types ◽  
The Impact ◽  
Insight Into

This article explores the impact of online crime victimisation. A literature review and 41 interviews – 19 with victims and 22 with experts – were carried out to gain insight into this. The interviews show that most impacts of online offences correspond to the impacts of traditional offline offences. There are also differences with offline crime victimisation. Several forms of impact seem to be specific to victims of online crime: the substantial scale and visibility of victimhood, victimisation that does not stop in time, the interwovenness of online and offline, and victim blaming. Victims suffer from double, triple or even quadruple hits; it is the accumulation of different types of impact, enforced by the limitlessness in time and space, which makes online crime victimisation so extremely invasive. Furthermore, the characteristics of online crime victimisation greatly complicate the fight against and prevention of online crime. Finally, the high prevalence of cybercrime victimisation combined with the severe impact of these crimes seems contradictory with public opinion – and associated moral judgments – on victims. Further research into the dominant public discourse on victimisation and how this affects the functioning of the police and victim support would be valuable.

scholarly journals Can Architectural Surfaces Capture Atmospheric Particulate Matter Like Trees? A Design Strategy to Mimic Leaf Traits

2021 ◽  
Vol 13 (14) ◽  
pp. 7637
Author(s):  
Taekyoung Lee ◽  
Jieun Cha ◽  
Sohyun Sung
Keyword(s):  
Leaf Traits ◽  
Design Strategy ◽  
Atmospheric Particulate Matter ◽  
Porous Surface ◽  
Base Surface ◽  
Different Types ◽  
Pm2.5 And Pm10 ◽  
Micro Morphology ◽  
The Impact ◽  
Cluster Pattern

Trees’ ability to capture atmospheric Particular Matter (PM) is related to morphological traits (shape, size, and micro-morphology) of the leaves. The objectives of this study were (1) to find out whether cluster pattern of the leaves is also a parameter that affects trees’ PM capturing performance and (2) to apply the cluster patterns of the leaves on architectural surfaces to confirm its impact on PM capturing performance. Two series of chamber experiments were designed to observe the impact of cluster patterns on PM capturing performance whilst other influential variables were controlled. First, we exposed synthetic leaf structures of different cluster patterns (a large and sparsely arranged cluster pattern and a small and densely arranged cluster pattern) to artificially generated PM in a chamber for 60 min and recorded the changing levels of PM2.5 and PM10 every minute. The results confirmed that the small and densely arranged cluster pattern has more significant effect on reducing PM2.5 and PM10 than the large and sparsely arranged cluster pattern. Secondly, we created three different types of architectural surfaces mimicking the cluster patterns of the leaves: a base surface, a folded surface, and a folded and porous surface. The surfaces were also exposed to artificially generated PM in the chamber and the levels of PM2.5 and PM10 were recorded. The results confirmed that the folded and porous surface has a more significant effect on reducing PM2.5 and PM10 than other surfaces. The study has confirmed that the PM capturing performance of architectural surfaces can be improved by mimicking cluster pattern of the leaves.

scholarly journals Threat or Corrective? Assessing the Impact of Populist Parties in Government on the Qualities of Democracy: A 19-Country Comparison

2021 ◽  
pp. 1-21
Author(s):  
Davide Vittori
Keyword(s):  
Negative Impact ◽  
Quality Of Democracy ◽  
Clear Cut ◽  
Liberal Democratic ◽  
Country Comparison ◽  
Democratic Regimes ◽  
Different Types ◽  
The Impact

Abstract Scholars have long debated whether populism harms or improves the quality of democracy. This article contributes to this debate by focusing on the impact of populist parties in government. In particular, it inquires: (1) whether populists in government are more likely than non-populists to negatively affect the quality of democracies; (2) whether the role of populists in government matters; and (3) which type of populism is expected to negatively affect the quality of liberal-democratic regimes. The results find strong evidence that the role of populists in government affects several qualities of democracy. While robust, the findings related to (2) are less clear-cut than those pertaining to (1). Finally, regardless of their role in government, different types of populism have different impacts on the qualities of democracy. The results show that exclusionary populist parties in government tend to have more of a negative impact than other forms of populism.

Sign in / Sign up

Export Citation Format

Share Document