The Influence of Tool Composite's Structure During Process of Diamond Grinding of Ceramic Materials

Abstract This paper presents the results of the tests performed during the grinding process of the ceramic materials: – polycrystalline ceramics (Zirconium ZrO2) and mono-crystalline ceramics (sapphire α-Al2O3) by the diamond tools. Studies have shown that the concentration (thickening) of the tool composite changes the tool's pore structure when using suitable wetted adamantine additives. Such modified composite has positive impact on tribological properties of the subsurface layer of the machined components. This is manifested by the reduction of the surface roughness and reduction of the vibration amplitude of the coefficient of friction. The possibilities of the positive effects when using wetted additives on the tool's composite during the pressing (briquetting) stage confirm the study results.

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The Influence of Amplitude on Grinding Force and Surface Roughness in Ultrasonic Assisted Grinding of K9 Glass

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1017.741 ◽

2014 ◽

Vol 1017 ◽

pp. 741-746

Author(s):

Fei Fei Zheng ◽

Fu Jian Ma ◽

Yi Dan Wang ◽

Zhi Gang Dong ◽

Ren Ke Kang

Keyword(s):

Surface Roughness ◽

Significant Influence ◽

Vibration Amplitude ◽

Grinding Force ◽

Machining Process ◽

Grinding Process ◽

Ultrasonic Assisted Grinding ◽

Ultrasonic Assisted ◽

Promising Solution ◽

K9 Glass

Ultrasonic assisted grinding (UAG) has been a promising solution for the machining of brittle materials. The vibration amplitude in UAG has significant influence on the machining process. In this paper, the experiments which apply UAG process on K9 glass were conducted to investigate the effect of amplitude upon grinding force and surface roughness. Theoretical calculation was done to explain the phenomenon observed and to analyze how vibration affects the grinding process. The conclusion is reached that the vibration amplitude should be cogitatively set to achieve better surface quality while realizing the reduction of the grinding force.

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Changes in Life Situations during the SARS-CoV-2 Virus Pandemic and Their Impact on Eating Behaviors for Residents of Europe, Australia as Well as North and South America

Nutrients ◽

10.3390/nu13103570 ◽

2021 ◽

Vol 13 (10) ◽

pp. 3570

Author(s):

Paulina Górska ◽

Ilona Górna ◽

Izabela Miechowicz ◽

Juliusz Przysławski

Keyword(s):

Physical Activity ◽

Eating Behavior ◽

Online Survey ◽

Positive Impact ◽

Working Hours ◽

Good Health ◽

Activity Levels ◽

Life Situation ◽

Positive Effects ◽

Study Results

Many people’s life situations are changing as a result of restrictions being imposed by national governments to limit the spread of the virus. These may be associated with additional factors (emotional or financial, for example) that influence eating behavior and physical activity levels. Therefore, the aim of this study was to show whether there is a relationship between a changing life situation during the pandemic and eating behavior as well as physical activity. An online survey was conducted between 28 April and 16 July 2020 with 921 participants from European countries and countries outside Europe (South and North America, Australia). An analysis of the obtained results showed an unfavorable relationship between a change in life situation during the pandemic and eating behavior as well as physical activity. This was observed mainly among students who returned to their family homes and respondents whose working hours increased. Students were more likely to snack between meals (51.13%, p < 0.001) and to consume more sweets (45.11%, p < 0.001) and savory snacks (30.83%, p < 0.001). Those whose working hours had increased, consumed morefast foods (13.57%, p < 0.05) during that time. On the other hand, the study results indicated that a change in life situation during the pandemic can also have a positive impact on eating behavior and physical activity. This was exhibited by individuals who transitioned to remote working. An improvement in the regularity of eating (38.86%, p < 0.001) was recorded for this group. The relationship between a change in life situation and eating behavior was further emphasized by the fact that people whose life situation had not changed were more likely to declare no change in the regularity of eating (62.86%, p < 0.001) and snacking (61.71%, p < 0.001). At the same time, they were less likely to exhibit a higher intake of sweets (22.29%, p < 0.01) and salty snacks (13.14%, p < 0.01). The study results indicated that a change in the nutritional situation during the pandemic may have had both negative and positive effects on eating behavior and physical activity. Finding these relationships may help identify groups that are particularly vulnerable to reduced diet quality and reduced levels of physical activity. Considering the immunomodulating effects of diets and the fact that physical activity is essential for maintaining good health, further research in this area is needed.

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Effect of ultrasonic oscillations on force and surface roughness in grinding process of Ti6Al4V titanium alloy

Mechanik ◽

10.17814/mechanik.2017.8-9.112 ◽

2017 ◽

Vol 90 (8-9) ◽

pp. 769-771

Author(s):

Janusz Porzycki ◽

Witold Habrat ◽

Marek Krok ◽

Marcin Żółkoś ◽

Marcin Sałata

Keyword(s):

Experimental Study ◽

Surface Roughness ◽

Titanium Alloy ◽

Grinding Force ◽

Grinding Process ◽

Ultrasonic Oscillations ◽

Ti6al4v Titanium Alloy ◽

Study Results ◽

Roughness Analysis ◽

Force Components

The paper presents the preliminary experimental study results in grinding process of Ti6Al4V titanium alloy. The aim of this study was to determine, through grinding force components and surface roughness analysis, what effect on this process has assisting it with workpiece ultrasonic oscillations.

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Experimental Research on Surface Roughness of Ultrasonic Assisted Grinding in Face Grinding Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.565.154 ◽

2012 ◽

Vol 565 ◽

pp. 154-159 ◽

Cited By ~ 2

Author(s):

Fei Hu Zhang ◽

L.F. Liu ◽

Chun Hui Li

Keyword(s):

Surface Roughness ◽

Experimental Research ◽

Feed Rate ◽

Vibration Amplitude ◽

Grinding Process ◽

Ultrasonic Assisted Grinding ◽

Ultrasonic Assisted ◽

Conventional Grinding ◽

Face Grinding ◽

K9 Glass

In this paper, the principle of ultrasonic assisted grinding is introduced. Experiments have been done to reveal the effect of different parameters(including feed rate, spindle speed, grinding depth, vibration amplitude on surface roughness of K9 glass both in ultrasonic assisted grinding and conventional grinding. The experiment results show that in face grinding process, the surface roughness of ultrasonic assisted grinding is worse than that of conventional grinding.

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Income Diversification and Bank Efficiency in Vietnam

Journal of Economics and Development ◽

10.33301/jed.2017.19.03.04 ◽

2017 ◽

pp. 52-67

Author(s):

Sang Nguyen Minh

Keyword(s):

Regression Model ◽

Commercial Banks ◽

Banking System ◽

Operational Efficiency ◽

Commercial Banking ◽

Tobit Regression ◽

Income Diversification ◽

Positive Effects ◽

Study Results ◽

The Impact

This study uses the DEA (Data Envelopment Analysis) method to estimate the technical efficiency index of 34 Vietnamese commercial banks in the period 2007-2015, and then it analyzes the impact of income diversification on the operational efficiency of Vietnamese commercial banks through a censored regression model - the Tobit regression model. Research results indicate that income diversification has positive effects on the operational efficiency of Vietnamese commercial banks in the research period. Based on study results, in this research some recommendations forpolicy are given to enhance the operational efficiency of Vietnam’s commercial banking system.

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The Effects of Technology Supports on Community Grocery Shopping Skills for Students With Intellectual and Developmental Disabilities: A Meta-Analysis

Journal of Special Education Technology ◽

10.1177/0162643421989970 ◽

2021 ◽

pp. 016264342198997

Author(s):

Sojung Jung ◽

Ciara Ousley ◽

David McNaughton ◽

Pamela Wolfe

Keyword(s):

Developmental Disabilities ◽

Positive Impact ◽

Single Case ◽

Effect Sizes ◽

Future Research ◽

Intellectual And Developmental Disabilities ◽

Positive Effects ◽

Analytic Review ◽

Wide Range ◽

The Impact

In this meta-analytic review, we investigated the effects of technology supports on the acquisition of shopping skills for students with intellectual and developmental disabilities (IDD) between the ages of 5 and 24. Nineteen single-case experimental research studies, presented in 15 research articles, met the current study’s inclusion criteria and the What Works Clearinghouse (WWC) standards. An analysis of potential moderators was conducted, and we calculated effect sizes using Tau-U to examine the impact of age, diagnosis, and type of technology on the reported outcomes for the 56 participants. The results from the included studies provide evidence that a wide range of technology interventions had a positive impact on shopping performance. These positive effects were seen for individuals across a wide range of ages and disability types, and for a wide variety of shopping skills. The strongest effect sizes were observed for technologies that provided visual supports rather than just auditory support. We provide an interpretation of the findings, implications of the results, and recommended areas for future research.

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Ayurveda Body–Mind Constitutional Types and Role of Yoga Intervention Among Type 2 Diabetes Mellitus Population of Chandigarh and Panchkula Regions

Annals of Neurosciences ◽

10.1177/09727531211000040 ◽

2021 ◽

pp. 097275312110000

Author(s):

Madhava Sai Sivapuram ◽

Vinod Srivastava ◽

Navneet Kaur ◽

Akshay Anand ◽

Raghuram Nagarathna ◽

...

Keyword(s):

Diabetes Mellitus ◽

Type 2 Diabetes ◽

Lipid Profiles ◽

Control Groups ◽

Yoga Intervention ◽

Positive Effects ◽

Study Results ◽

Significant Difference ◽

And Control

Background: Type 2 diabetes needs a better understanding of etiological factors and management strategies based on lifestyle and constitutional factors, given its high association rate with many cardiovascular, neurological disorders, and COVID-19 infection. Purpose: The present study was undertaken to investigate the effect of Diabetes-specific integrated Yoga lifestyle Protocol (DYP) on glycemic control and lipid profiles of diabetic adults. Along with the DYP intervention, the individuals residing in Chandigarh and Panchkula union territories in the northern part of India were assessed for Ayurveda-based body–mind constitutional type. Ayurveda describes body–mind constitution as “ prakriti,” which has been discussed from two angles, namely physiological and psychological as body and mind are correlated. Methods: Cluster sampling of waitlist control study subjects was used as the sampling method for the study. A total of 1,215 registered subjects (81 diabetic) responded in randomly selected clusters in Chandigarh and Panchkula. Ayurveda physicians did Ayurveda body–mind constitutional assessment called prakriti assessment (physiological body–mind constitution assessment) in 35 participants (23 diabetic, 12 prediabetic) as a part of the study. Results: A group of 50 subjects was randomly selected for yoga intervention out of 81 diabetes mellitus adults, and 31 subjects were enrolled as waitlist controls. A significant decrease in the glycosylated hemoglobin levels from 8.49 ± 1.94% to 7.97 ± 2.20% in the intervention group was noticed. The lipid profiles of the DYP intervention and control groups were monitored. Three-month follow-up results of lipid profile diagnostic tests in intervention and control groups showed a significant difference between the two groups ( P < 0.05). Most diabetic and prediabetic individuals were found to have pitta dosha ( pitta controls all heat, metabolism, and transformation in the mind and body) as dominant constitution type. Conclusion: The study results demonstrated significant positive effects of yoga in diabetic individuals. This study has indicated the evidence for the safety and efficacy of the validated DYP for community-level interventions to prevent maladies like brain damage and stroke.

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The Influence of Dynamic and Adaptive Marketing Capabilities on the Performance of Portuguese SMEs in the B2B International Market

Sustainability ◽

10.3390/su13020579 ◽

2021 ◽

Vol 13 (2) ◽

pp. 579

Author(s):

Caroline Reimann ◽

Fernando Carvalho ◽

Marcelo Duarte

Keyword(s):

Positive Impact ◽

International Marketing ◽

International Market ◽

Marketing Capabilities ◽

Moderating Effects ◽

Competitive Intensity ◽

Positive Effects ◽

Marketing Performance ◽

Market Learning ◽

Positive Effect

The present investigation aims study the sustainability of the business model of the Portuguese SMEs operating in the B2B International market analyzing the influence of dynamic marketing capabilities and adaptive marketing capabilities in their international marketing performance. It will also analyze the moderating effects of Competitive Intensity within this international scenario. A quantitative study was developed, using a questionnaire as a research method. In total, 335 valid responses were collected from Portuguese SMEs in June 2020. To test the hypotheses, multiple hierarchical regressions were performed. As for the analyzes involving Competitive Intensity environments, namely low and high intensity, dummies were developed to evaluate the different effects produced by the capacities in the International Marketing Performance. This study shows the positive impact of the dynamic marketing capabilities and adaptive marketing capabilities on the international marketing performance of the surveyed companies, essentially from the product development management, supply chain management, vigilant market learning and open marketing. when in a low competitive intensity environment only dynamic marketing capabilities had a positive effect on performance, but in a high, competitive, intensity environment both dynamic marketing capabilities and adaptive marketing capabilities showed positive effects in relation to performance. This study innovates by bringing international marketing, through two marketing capacities, from the perspective of SMEs that perform B2B activities.

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Paleolithic Diet—Effect on the Health Status and Performance of Athletes?

Nutrients ◽

10.3390/nu13031019 ◽

2021 ◽

Vol 13 (3) ◽

pp. 1019

Author(s):

Barbara Frączek ◽

Aleksandra Pięta ◽

Adrian Burda ◽

Paulina Mazur-Kurach ◽

Florentyna Tyrała

Keyword(s):

Blood Pressure ◽

Body Mass ◽

Positive Impact ◽

Model Assessment ◽

Paleolithic Diet ◽

Short Term ◽

Positive Effects ◽

Short And Long Term ◽

The Impact

The aim of this meta-analysis was to review the impact of a Paleolithic diet (PD) on selected health indicators (body composition, lipid profile, blood pressure, and carbohydrate metabolism) in the short and long term of nutrition intervention in healthy and unhealthy adults. A systematic review of randomized controlled trials of 21 full-text original human studies was conducted. Both the PD and a variety of healthy diets (control diets (CDs)) caused reduction in anthropometric parameters, both in the short and long term. For many indicators, such as weight (body mass (BM)), body mass index (BMI), and waist circumference (WC), impact was stronger and especially found in the short term. All diets caused a decrease in total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG), albeit the impact of PD was stronger. Among long-term studies, only PD cased a decline in TC and LDL-C. Impact on blood pressure was observed mainly in the short term. PD caused a decrease in fasting plasma (fP) glucose, fP insulin, and homeostasis model assessment of insulin resistance (HOMA-IR) and glycated hemoglobin (HbA1c) in the short run, contrary to CD. In the long term, only PD caused a decrease in fP glucose and fP insulin. Lower positive impact of PD on performance was observed in the group without exercise. Positive effects of the PD on health and the lack of experiments among professional athletes require longer-term interventions to determine the effect of the Paleo diet on athletic performance.

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Study on the Effect of Grinding Pressure on Material Removal Behavior Performed on a Self-Designed Passive Grinding Simulator

Applied Sciences ◽

10.3390/app11094128 ◽

2021 ◽

Vol 11 (9) ◽

pp. 4128

Author(s):

Peng-Zhan Liu ◽

Wen-Jun Zou ◽

Jin Peng ◽

Xu-Dong Song ◽

Fu-Ren Xiao

Keyword(s):

Residual Stress ◽

Surface Roughness ◽

Service Life ◽

Material Removal ◽

Removal Rate ◽

Grinding Force ◽

Grinding Wheel ◽

Grinding Process ◽

Grinding Temperature ◽

Grinding Efficiency

Passive grinding is a new rail grinding strategy. In this work, the influence of grinding pressure on the removal behaviors of rail material in passive grinding was investigated by using a self-designed passive grinding simulator. Meanwhile, the surface morphology of the rail and grinding wheel were observed, and the grinding force and temperature were measured during the experiment. Results show that the increase of grinding pressure leads to the rise of rail removal rate, i.e., grinding efficiency, surface roughness, residual stress, grinding force and grinding temperature. Inversely, the enhancement of grinding pressure and grinding force will reduce the grinding ratio, which indicates that service life of grinding wheel decreases. The debris presents dissimilar morphology under different grinding pressure, which reflects the distinction in grinding process. Therefore, for rail passive grinding, the appropriate grinding pressure should be selected to balance the grinding quality and the use of grinding wheel.

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