Performance Evaluation of Additives to Make Abrasion Resistant Concrete: A Review

2021 ◽  
Vol 9 (11) ◽  
pp. 747-755
Author(s):  
Sneha Benoy
Keyword(s):  
Performance Evaluation ◽  
Degradation Mechanism ◽  
Research Work ◽  
Concrete Structures ◽  
Structural Safety ◽  
Strength Gain ◽  
Negative Effects ◽  
Resistance Level ◽  
Factors Affecting ◽  
The Cost

Abstract: One of the most common forms of deterioration of concrete structures is by surface abrasion. Abrasion primarily depends upon the resistance level of materials, mix composition, strength gain and construction practices. Such deteriorations endanger the structural safety and increase the cost of repair and maintenance. In order to minimize the maintenance problems and to increase the serviceability of the structures, it is important that the structure should be resistant to abrasion. Understanding the physics of abrasion is critical for reducing its negative effects on concrete because abrasion is a typical degradation mechanism for concrete. An effort has been spent to identify the factors affecting abrasion of concrete structures and a review on different additives that can be added to achieve abrasion-resistant concrete is carried out. This paper reviews the research work carried out in the area of surface abrasion with works focusing within the last decade. Keywords: Abrasion Resistance, Additives, Concrete Abrasion, Degradation, Durability, Serviceability.

Latest Developments in Performance Evaluation of Concrete Structures under Fire Conditions

2017 ◽  
Vol 55 (11) ◽  
pp. 961-967
Author(s):  
M. Kanematsu ◽  
M. Ozawa ◽  
T. Morita ◽  
S. Uchida ◽  
T. Tanibe
Keyword(s):  
Performance Evaluation ◽  
Concrete Structures ◽  
Fire Conditions

Erfolg der Jungwaldpflege im Schweizer Mittelland? Analyse und Folgerungen (Essay)

2013 ◽  
Vol 164 (9) ◽  
pp. 262-270 ◽  
Author(s):  
Peter Ammann
Keyword(s):  
Stand Development ◽  
Negative Effects ◽  
Tree Species Composition ◽  
Natural Processes ◽  
Course Of Action ◽  
Tree Thinning ◽  
Swiss Plateau ◽  
Self Differentiation ◽  
The Cost ◽  
Young Growth

Is young growth tending successful in the Swiss Plateau region? Analysis and implications (essay) The effect of the cost-intensive young growth tending used up to the present in the region of the Swiss Plateau is analysed using different approaches. It is evident that young growth tending is not only ineffective with respect to diameter growth but even hinders stand development. Negative effects on quality from young growth tending are also recognised. This is often due to premature interventions in the natural processes of self-differentiation and subsequent systematic errors in the thinning. Furthermore, the effect of tending measures on the tree species composition is often overestimated because in the first 10 to 20 years of stand development, it is primarily the rejuvenation strategy and the site which are decisive. As an alternative course of action, tending concepts are proposed which rely on biological rationalisation and future tree thinning, to achieve future trees which are as vigorous as possible. These are not only more effective, but are also significantly less expensive.

scholarly journals Risk of Increased Acceptance for Organizational Nepotism and Cronyism during the COVID-19 Pandemic

Risks ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 59
Author(s):  
Grzegorz Ignatowski ◽  
Łukasz Sułkowski ◽  
Bartłomiej Stopczyński
Keyword(s):  
Qualitative Study ◽  
Quantitative Methods ◽  
Research Work ◽  
Negative Effects ◽  
Qualitative And Quantitative ◽  
Qualitative And Quantitative Methods ◽  
Work Related ◽  
Social And Economic Development ◽  
The Times ◽  
The Impact

Nepotism and cronyism are forms of favoritism towards certain people in the workplace. For this reason, they constitute a problem for organization managers, ethicists and psychologists. Identifying the impact of COVID-19 pandemic on the increase of nepotism and cronyism may provide a basis for organizations to assess their extent and to take possible measures to prevent their negative effects. At the same time, the research presented in the article may provide a basis for further research work related to nepotism and cronyism at the times of other threats, different from the pandemic. The aim of the article is to examine the impact of the COVID-19 pandemic on growing acceptance for nepotism and cronyism in Polish enterprises. Qualitative and quantitative methods have been included in the conducted research. Qualitative study aimed at improving knowledge of nepotism and cronyism and the impact of the COVID-19 pandemic on these phenomena, followed by a quantitative study conducted in order to verify the information obtained in the qualitative study. This research has demonstrated that Nepotism and cronyism in the workplace, are phenomenon that are basically evaluated negatively. They adversely influences social and economic development, but the impact of COVID-19 pandemic on nepotism and cronyism is not significant.

scholarly journals Factors Affecting the Rate of Fuel Consumption in Aircrafts

2021 ◽  
Vol 13 (14) ◽  
pp. 8066
Author(s):  
Thowayeb H. Hassan ◽  
Abu Elnasr E. Sobaih ◽  
Amany E. Salem
Keyword(s):  
Fuel Consumption ◽  
Positive Association ◽  
Pollutant Emissions ◽  
Aviation Industry ◽  
Factors Affecting ◽  
Fuel Flow ◽  
Homogeneity Of Variance ◽  
Strong Positive Association ◽  
Ground Distance ◽  
The Cost

The cost of fuel and its availability are among the most major concerns for aircrafts and the aviation industry overall. Environmental difficulties with chemical pollutant emissions emitted by aviation machines are also connected to fuel consumption. As a result, it is crucial to examine factors that affect the overall fuel usage and consumption in the airport-based aviation industry. Several variables were investigated related to the total fuel consumed, such as dry operating weight (DOW) (KG), zero-fuel weight (ZFW), take-off weight (TOW), air distance (AIR DIST) (KM), and ground distance (GDN DIST). Analysis of the correlation between total fuel consumed as well as the extra fuel and selected variables was conducted. The results showed that the most positively associated factors with the total used fuel were the air distance (r2 = 0.86, p < 0.01), ground distance (r2 = 0.78, p < 0.01), TOW (r2 = 0.68, p < 0.01), and flight time (r2 = 0.68, p < 0.01). There was also a strong positive association between the average fuel flow (FF) and actual TOW (r2 = 0.74, p < 0.01) as well as ZFW (r2 = 0.61, p < 0.01). The generalized linear model (GLM) was utilized to assess the predictions of total energy usage after evaluating important outliers, stability of the homogeneity of variance, and the normalization of the parameter estimation. The results of multiple linear regression revealed that the most significant predictors of the total consumed fuel were the actual ZFW (p < 0.01), actual TOW (p < 0.01), and actual average FF (p < 0.05). The results interestingly confirmed that wind speed has some consequences and effects on arrival fuel usage. The result reflects that thermal and hydrodynamic economies impact on the flying fuel economy. The research has various implications for both scholars and practitioners of aviation industry.

scholarly journals Development of Performance Evaluation Indicators for Table Grape Packaging Units

2021 ◽  
Vol 13 (4) ◽  
pp. 2177
Author(s):  
Edson Kogachi ◽  
Adonias Ferreira ◽  
Carlos Cavalcante ◽  
Marcelo Embiruçu
Keyword(s):  
Performance Evaluation ◽  
Standard Deviation ◽  
Process Management ◽  
Principal Component ◽  
Table Grape ◽  
Data Envelopment ◽  
Table Grapes ◽  
Speed Performance ◽  
The Cost

In order to improve the process management of table grape packaging, its performance should be evaluated. However, the literature on performance evaluation indicators is scarce. To address this research gap, we propose a method for the development of performance evaluation indicators for table grape packaging units, which are characterized by labor-intensive and highly seasonal production processes in the agro-economic sector. The stages include the following: contextualizing table grape packaging units, selecting the performance objectives, selecting techniques to be used in the development of the indicators, and applying the method to the packaging units of table grapes. The techniques adopted in the development of the indicators aimed at the cost, quality, flexibility, reliability, and speed performance objectives were data envelopment analysis, principal component analysis, quantification of the batch, compliance with the program within the established deadline, and measurement of the execution time of the batch, respectively. The results obtained in the case study demonstrate that the correlations between the performance indicators do not indicate the need to disregard any of them. Furthermore, the standard deviation values for each indicator are similar. Thus, both results of correlations and standard deviation confirm the importance of the indicators chosen for the performance evaluation of table grape packaging.

scholarly journals Economic burden of childhood diarrhea in Burundi

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Fulgence Niyibitegeka ◽  
Arthorn Riewpaiboon ◽  
Sitaporn Youngkong ◽  
Montarat Thavorncharoensap
Keyword(s):  
Economic Burden ◽  
Cost Model ◽  
Primary Treatment ◽  
Management Program ◽  
Community Based ◽  
Factors Affecting ◽  
Hospitalization Costs ◽  
Illness Study ◽  
The Cost ◽  
Substantial Economic Burden

Abstract Background In 2016, diarrhea killed around 7 children aged under 5 years per 1000 live births in Burundi. The objective of this study was to estimate the economic burden associated with diarrhea in Burundi and to examine factors affecting the cost to provide economic evidence useful for the policymaking about clinical management of diarrhea. Methods The study was designed as a prospective cost-of-illness study using an incidence-based approach from the societal perspective. The study included patients aged under 5 years with acute non-bloody diarrhea who visited Buyenzi health center and Prince Regent Charles hospital from November to December 2019. Data were collected through interviews with patients’ caregivers and review of patients’ medical and financial records. Multiple linear regression was performed to identify factors affecting cost, and a cost model was used to generate predictions of various clinical and care management costs. All costs were converted into international dollars for the year 2019. Results One hundred thirty-eight patients with an average age of 14.45 months were included in this study. Twenty-one percent of the total patients included were admitted. The average total cost per episode of diarrhea was Int$109.01. Outpatient visit and hospitalization costs per episode of diarrhea were Int$59.87 and Int$292, respectively. The costs were significantly affected by the health facility type, patient type, health insurance scheme, complications with dehydration, and duration of the episode before consultation. Our model indicates that the prevention of one case of dehydration results in savings of Int$16.81, accounting for approximately 11 times of the primary treatment cost of one case of diarrhea in the community-based management program for diarrhea in Burundi. Conclusion Diarrhea is associated with a substantial economic burden to society. Evidence from this study provides useful information to support health interventions aimed at prevention of diarrhea and dehydration related to diarrhea in Burundi. Appropriate and timely care provided to patients with diarrhea in their communities and primary health centers can significantly reduce the economic burden of diarrhea. Implementing a health policy to provide inexpensive treatment to prevent dehydration can save significant amount of health expenditure.

Factors affecting the future of the Scottish hydrometric network

1987 ◽  
Vol 78 (4) ◽  
pp. 269-274 ◽  
Author(s):  
T. Poodle
Keyword(s):  
Data Acquisition ◽  
Computer Systems ◽  
Economic Recession ◽  
Data Standards ◽  
Factors Affecting ◽  
Economic Climate ◽  
A Minor ◽  
The Cost ◽  
Minor Extent

ABSTRACTThe Scottish Hydrometric Network consists of a number of river gauging stations which have been located at sites considered suitable to provide long term flow records. Economic recession has placed some stress on the gauging programme, and has given rise to extensive closures of gauging stations in England and, to a minor extent so far, in Scotland. The way in which the network became established provides a mixture of strengths and weaknesses which could have unpredictable consequences in an adverse economic climate. Changing technology provides some opportunity to reduce the cost of data acquisition and improve the deployment of manpower, while maintaining data standards. In these changing circumstances, particularly with extensive use of computer systems, it is important that standards are established for data returned to the Water Archive and that the network is not allowed to degenerate by default.

Mechanical Analysis of Warm Extrusion Precision Forming on 42CrMo Steel Cutting Pick

2012 ◽  
Vol 538-541 ◽  
pp. 1061-1066 ◽  
Author(s):  
Chun Jian Su ◽  
Quan Lan Li ◽  
Lin Jing Xiao ◽  
Su Min Guo
Keyword(s):  
New Technology ◽  
Mechanical Analysis ◽  
Extrusion Force ◽  
Factors Affecting ◽  
42Crmo Steel ◽  
Pick Body ◽  
Mining Tool ◽  
Main Factors ◽  
The Cost ◽  
Warm Extrusion

Cutting pick is a kind of widely-used consumptive mining tool. The traditional producing technics of cutting pick body is foundry, or machining after roughly forging, or machining directly from metal bar. By former technics, the property of products is poor, and by latter, the material availability is low and the cost is high. The patent technology for cutting pick body warm extrusion introduced in this paper can overcome all the disadvantages mentioned above. In this paper, by analyzing the characteristic of cutting pick body warm extrusion, adopting the principle of power balance to solve the approximate solution of strain forces, the approximate calculating formulas of extruding power are deduced. The main factors affecting on extrusion force are determined theoretically. This research can be used as basis to design tooling and choose proper equipment for this new technology.

scholarly journals Degradation Behavior of Polymers Used as Coating Materials for Drug Delivery—A Basic Review

Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1272
Author(s):  
Anita Ioana Visan ◽  
Gianina Popescu-Pelin ◽  
Gabriel Socol
Keyword(s):  
Drug Delivery ◽  
Degradation Mechanism ◽  
Degradation Behavior ◽  
Polymeric Coatings ◽  
Degradation Mechanisms ◽  
Coating Materials ◽  
Factors Affecting ◽  
Existing Problems ◽  
Future Performance ◽  
Measuring Techniques

The purpose of the work was to emphasize the main differences and similarities in the degradation mechanisms in the case of polymeric coatings compared with the bulk ones. Combined with the current background, this work reviews the properties of commonly utilized degradable polymers in drug delivery, the factors affecting degradation mechanism, testing methods while offering a retrospective on the evolution of the controlled release of biodegradable polymeric coatings. A literature survey on stability and degradation of different polymeric coatings, which were thoroughly evaluated by different techniques, e.g., polymer mass loss measurements, surface, structural and chemical analysis, was completed. Moreover, we analyzed some shortcomings of the degradation behavior of biopolymers in form of coatings and briefly proposed some solving directions to the main existing problems (e.g., improving measuring techniques resolution, elucidation of complete mathematical analysis of the different degradation mechanisms). Deep studies are still necessary on the dynamic changes which occur to biodegradable polymeric coatings which can help to envisage the future performance of synthesized films designed to be used as medical devices with application in drug delivery.

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