Experimental Comparison of Speed-Dependent Rolling Coefficients in Small Cycling Tires

2020 ◽  
Author(s):  
Paolo Baldissera ◽  
Cristiana Delprete ◽  
Mattia Rossi ◽  
Anatolii Zahar
Keyword(s):  
High Speed ◽  
Rolling Resistance ◽  
Resistance Coefficient ◽  
Theoretical Background ◽  
Experimental Comparison ◽  
Energetic Cost ◽  
Racing Performance ◽  
Significant Difference ◽  
Latex Tube ◽  
The Impact

ABSTRACT In this article, the methodology and results of an experimental campaign on small and slick bicycle tires are presented. The test was developed to compare the rolling resistance of tires to be used in high-speed competitions for streamlined human-powered vehicles. After an explanation of the theoretical background for the measurement, the test-rig and the adopted procedure to measure and subtract aerodynamic effects are presented. The obtained data show that the rolling resistance coefficient has a nonlinear dependency from the speed between 45 and 145 km/h. The data comparison points out a decrease in rolling losses up to 54% by switching from a butyl to latex inner tube on the same tire, whereas no significant difference is detected between the latex tube and tubeless configuration. An estimation of the impact on racing performance is provided, showing that selecting the best option could save up to 19% of the overall effort energetic cost, which means a higher final speed can be achieved with the same rider effort. Finally, a speculative analysis is proposed that considers different functions to fit the obtained data, pointing out the need for experimental measurements on the very-low-speed region to achieve a better understanding of the entire rolling resistance behavior with respect to speed.

scholarly journals An Experimental Comparison of the Impact of ‘Warning’ and ‘Health Star Rating’ FoP Labels on Adolescents’ Choice of Breakfast Cereals in New Zealand

Nutrients ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1545 ◽  
Author(s):  
Robert Hamlin ◽  
Benjamin Hamlin
Keyword(s):  
New Zealand ◽  
Experimental Comparison ◽  
Vienna Convention ◽  
Single Star ◽  
Star Rating ◽  
Stop Sign ◽  
Significant Difference ◽  
Nutritional Label ◽  
The Difference ◽  
The Impact

This research investigated the performance of the red, octagonal Vienna Convention traffic ‘STOP’ sign as a front of pack (FoP) warning nutritional label. While the Vienna Convention traffic light system is an established FoP label, the potential of the ‘STOP’ sign in the role has not been investigated. The performance of the ‘STOP’ label was compared with that of a single star (low nutritional value) Australasian Health Star Rating (HSR) label using a fractionally replicated Latin square design. The labels were presented on choice diads of cold breakfast cereal packets. The sample of 240 adolescents aged 16–18 was drawn from a secondary school in the South Island of New Zealand. A large and significant main effect was observed at the p < 0.01 level for the difference between the ’STOP’ sign and the control condition (no nutritional FoP label), and at p < 0.05 for the difference between the HSR and the ‘STOP’ label. There was no significant difference between the HSR FoP and the control condition. A significant non-additivity (interaction) (p < 0.01) was also observed via the fractional replication. The results indicate that the Vienna Convention ‘STOP’ sign is worthy of further research with regard to its potential as an FoP nutritional label.

Do hotel business benefit from increased tourist accessibility? Evidence from China’s high-speed railway program

2020 ◽  
pp. 135481662092321
Author(s):  
Taotao Deng ◽  
Chen Gan ◽  
Yukun Hu
Keyword(s):  
High Speed ◽  
Occupancy Rate ◽  
High Speed Railway ◽  
Positive Effects ◽  
Luxury Hotels ◽  
Hotel Performance ◽  
Significant Difference ◽  
Transportation Accessibility ◽  
Occupancy Rates ◽  
The Impact

The operation of high-speed railway (HSR) always plays a key role in promoting tourism development of city by improving transportation accessibility and facilitating tourists’ travel. Based on the panel data of 50 major tourist cities in China from 2010 to 2017, this article uses a Tobit model to explore the impact of HSR service on hotel performance that is embodied in occupancy rate. The results show that with other factors unchanged, the cities with a high-frequency HSR service system or hub HSR station tend to have higher hotel occupancy rate. Moreover, the hotel occupancy rate of cities with a suburb HSR station is lower than that of other HSR-served cities. After classifying hotels into luxury and budget groups, this article finds that HSR train frequency and station grade still show positive effects on both luxury and budget hotels. However, in cities with suburb HSR stations, budget hotels tend to have lower occupancy rates, while occupancy rate for luxury hotels shows no significant difference.

A Simulated and Experimental Comparison of Lead-Free and Tin-Lead Solder Interconnect Failure Under Impact Stimuli

2005 ◽  
Author(s):  
Greg Heaslip ◽  
Jeff Punch ◽  
Bryan Rogers ◽  
Claire Ryan ◽  
Michael Reid
Keyword(s):  
Failure Analysis ◽  
High Speed ◽  
Lead Free ◽  
Experimental Comparison ◽  
Lead Free Solder ◽  
Fe Method ◽  
Explicit Finite Element ◽  
Free Solder ◽  
Peel Stress ◽  
The Impact

There is considerable reported evidence that a large percentage of failures which afflict portable electronic products are due to impact or shock during use. Failures of the external housing, internal electronic components, package-to-board interconnects, and liquid crystal display panels may occur as the result of accidental drops. Moreover, the introduction of lead-free solder to the electronics industry will bring additional design implications for future generations of mobile electronic systems. In this paper, drop tests performed on PCBs populated with ball grid arrays (BGAs) are reported. During testing, measurements from strain gages were recorded using a high-speed data acquisition system. Electrical continuity through each package was monitored during the impact event in order to detect failure of package-to-board interconnects. Life distributions were established for both a lead-free and a tin-lead solder for various drop heights. In addition, failure analysis was carried out using microsection techniques, scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). Resistance measurements throughout the drop event indicated that different failure mechanisms occurred for different drop heights. The explicit finite element (FE) method was employed to evaluate the peel stress at the critical solder joint and a stress-life model is then established for the lead-free solder. The maximum peel stress location was found to match the location of failure initiation revealed from the failure analysis. It was also discovered that, for board level drop testing, that there is a considerable difference between the lead-free solder characteristic life and the tin-lead solder characteristic life.

scholarly journals The Impact of E - Accounting in Modern Businesses

2019 ◽  
Vol 4 (2) ◽  
pp. 1-4 ◽  
Author(s):  
Susan Peter Teru ◽  
Innocent Felix Idoko ◽  
Lukman Bello
Keyword(s):  
High Speed ◽  
Technological Development ◽  
Secondary Data ◽  
Poor Quality ◽  
Theoretical Background ◽  
Accounting System ◽  
Digital Revolution ◽  
Modern Business ◽  
The Impact ◽  
Speed Accuracy

There has been constant growth and development in information technology which had brought the digital revolution in our daily economic, social and cultural fields. This technological development changed the methods and ways of carrying out tasks within the scope of accounting transactions and activities through the use of electronic media. One of the digital applications produced on this issue is E- accounting.  E- accounting is a new development in the field of accounting adopted at the international level. E- accounting stands for electronic accounting with the characteristics of high speed, accuracy and with an immediate result. Accordingly, source documents and accounting records exist in a digital form instead of on paper in an electronic accounting system.  It helps businesses keep their financial data and accounting software in a safe, secure environment allowing real-time access to authorized users irrespective of their location or computing platforms. This paper sheds light on the impact of e-accounting in the modern business, the concept of E- accounting, benefits, and problems of e- accounting. The main source of data used for this paper is the secondary data from the review of related literature basically to create a theoretical background for the study. It was found from the studies that many organizations fail in the business, not because of poor quality of material, not the availability of trained staff, management problems, but the main reason is the accounting practices adopted by the businesses. Therefore, there is a need for businesses to adopt e -accounting practices as a replacement for traditional practices.

Bioinspired Crown-Cutter—The Impact of Tooth Quantity and Bevel Type on Tissue Deformation, Penetration Forces, and Tooth Collapsibility

2014 ◽  
Vol 8 (4) ◽  
Author(s):  
Filip Jelínek ◽  
Jeffrey Goderie ◽  
Alice van Rixel ◽  
Daan Stam ◽  
Johan Zenhorst ◽  
...  
Keyword(s):  
High Speed ◽  
Surface Deformation ◽  
Testing Machine ◽  
High Ratio ◽  
Steady Increase ◽  
Tissue Deformation ◽  
Universal Testing ◽  
Significant Difference ◽  
The Impact ◽  
Speed And Accuracy

Current keyhole biopsy devices are rather ungainly, inaccurate, and limited in application. A keyhole biopsy harvester was designed to facilitate peripheral cancerous tissue detection and resection at high speed and accuracy. The harvester's cutting tool, the crown-cutter, was bioinspired by the sea urchin's chewing organ—Aristotle's lantern. This paper focuses on the optimization of the crown-cutter with regard to the impact of different tooth quantity and bevel type on tissue deformation, penetration forces, and tooth collapsibility. Two sets of crown-cutter designs were manufactured and tested in push-in experiments using gelatin—the first set having no bevel and differing tooth quantity (4, 6, 8, 10 teeth) and the second set of constant tooth quantity and differing bevel type (no, inner, outer, and inner and outer bevel). The gelatin surface deformation and the penetration forces were evaluated utilizing a high speed camera and a universal testing machine, respectively. The experimental results on the crown-cutters of different tooth quantity (no bevel) showed a steady increase in the tissue deformation with the increasing amount of teeth. Unlike the bevel type, the different tooth quantity revealed significant differences with regard to the tissue deformation in between 4 versus 6-teeth and 10 versus 6-teeth cutters. As for the penetration forces, the significant difference was found only between 10 and 6-teeth cutters. In conclusion, reducing the cutter's tooth quantity resulted in lower tissue deformation, whereas differing the bevel type was found to have a negligible influence. Ultimately, a high ratio of outward to inward tooth collapsibility and a relatively low inner moment of inertia proved the 6-teeth cutter to be the most optimal.

Measuring Impact of Stress in Sandwich Generation Caring for Demented Parents

GeroPsych ◽  
2014 ◽  
Vol 27 (4) ◽  
pp. 171-179 ◽  
Author(s):  
Laurence M. Solberg ◽  
Lauren B. Solberg ◽  
Emily N. Peterson
Keyword(s):  
Factor Analysis ◽  
Exploratory Factor Analysis ◽  
Social Worker ◽  
Resource Availability ◽  
Well Being ◽  
Sandwich Generation ◽  
Item Questionnaire ◽  
Significant Difference ◽  
Adult Caregivers ◽  
The Impact

Stress in caregivers may affect the healthcare recipients receive. We examined the impact of stress experienced by 45 adult caregivers of their elderly demented parents. The participants completed a 32-item questionnaire about the impact of experienced stress. The questionnaire also asked about interventions that might help to reduce the impact of stress. After exploratory factor analysis, we reduced the 32-item questionnaire to 13 items. Results indicated that caregivers experienced stress, anxiety, and sadness. Also, emotional, but not financial or professional, well-being was significantly impacted. There was no significant difference between the impact of caregiver stress on members from the sandwich generation and those from the nonsandwich generation. Meeting with a social worker for resource availability was identified most frequently as a potentially helpful intervention for coping with the impact of stress.

Implicit and explicit corrective feedback and feedback exposure conditions

2020 ◽  
Vol 4 (1) ◽  
pp. 3-48
Author(s):  
Takehiro Iizuka ◽  
Kimi Nakatsukasa
Keyword(s):  
Explicit Knowledge ◽  
Corrective Feedback ◽  
Significant Difference ◽  
Oral Corrective Feedback ◽  
Post Test ◽  
Picture Description ◽  
Potential Factors ◽  
Implicit And Explicit ◽  
Instructional Settings ◽  
The Impact

This exploratory study examined the impact of implicit and explicit oral corrective feedback (CF) on the development of implicit and explicit knowledge of Japanese locative particles (activity de, movement ni and location ni) for those who directly received CF and those who observed CF in the classroom. Thirty-six college students in a beginning Japanese language course received either recast (implicit), metalinguistic (explicit) or no feedback during an information-gap picture description activity, and completed a timed picture description test (implicit knowledge) and an untimed grammaticality judgement test (explicit knowledge) in a pre-test, immediate post-test and delayed post-test. The results showed that overall there was no significant difference between CF types, and that CF benefited direct and indirect recipients similarly. Potential factors that might influence the effectiveness of CF, such as instructional settings, complexity of target structures and pedagogy styles, are discussed.

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