On-Road Evaluation of Energy Cost on Cycling: A Case Study for Analyzing Tire Pressure Influence

2015 ◽  
Author(s):  
Sergio Daniel Roa ◽  
Luis Ernesto Muñoz
Keyword(s):  
Energy Cost ◽  
Rolling Resistance ◽  
Input Power ◽  
Tire Pressure ◽  
Direct Evaluation ◽  
Multiple Parameters ◽  
The Mean ◽  
Level Of Significance ◽  
Resistance Coefficients

This work presents a methodology for the evaluation of energy cost on cycling through on-road tests. The proposed methodology consists on the measurement of the power delivered by the cyclist on the pedals when riding on a real circuit. The aim of the methodology is to generate indexes for the direct evaluation of the effect on energy cost generated by an arbitrary modification implemented on a bike. The modification can include the variation of multiple parameters. The proposed indexes for the evaluation of the energy cost are the mean input power and the mechanical work per distance during the test. The proposed methodology intends to evaluate the energy cost for a given bike-rider set on a given circuit. A case study is presented for the evaluation of tire pressure influence on energy cost. For the application of the methodology, one cyclist rode on the circuit of interest with a set of different tire pressures. The power delivered by the cyclist was measured on the pedals. Several tests were conducted for each pressure in order to achieve a good level of significance. The results obtained for the case study with the proposed methodology are compared with the results of a method based on rolling resistance coefficients reported in literature.

scholarly journals Improving Students Speaking Ability Through Debate in The Classroom ( A Case Study for Students at Second Years Students’s of SMAN 3 Kota Bima in Academic Year 2017/2018)

2019 ◽  
Vol 6 (1) ◽  
pp. 229
Author(s):  
Emi Elmiyati
Keyword(s):  
Experimental Research ◽  
T Test ◽  
Deviation Score ◽  
Post Test ◽  
Control Research ◽  
The Mean ◽  
Level Of Significance ◽  
And Control ◽  
Academic Year

This study aims to investigate the improvement of speaking ability through debate in the classroom and to investigate the students’s response toward the use of debate in teaching speaking at SMAN 3 kota Bima in academic year 2017/2018. In this study adopted experimental research design with method of collecting data used test and questionnaire, while technique for analysing data in this study based on quantities through data gained in the t-test formula. After analysing the data. It found the mean score of post-test by experimental research was higher than mean score of post-test by control research. Deviation score of post-test experimental class is 12 and control class is 5,93 and the square of deviation score of experimental class ≥ the square of deviation score of control class (1509 ≥ 287,87). It indicates that the treatment was succesful, more over significance value of the t-test also was higher than of the t-table (3,27 ≥ 2,021 = 95% and 3,27 ≥ 2,704 = 99%). The level of significance is 0,05% and 0,01% with degree of freedom (df) 58. It’s mean that Ha is accepted and Ho is refused. Not only research the treatment progress in experimental class and t-test in this study but also more response in using debate method in the classroom through questionnaire which have significant result 82,67% by respondents. This study concludes that debate method can improve students speaking ability in the classroom and has very positive response from students.

scholarly journals Propulsive efficiency of alternative underwater flykick techniques for swimmers

2020 ◽  
pp. 175433712091261
Author(s):  
Christopher WG Phillips ◽  
Alexander IJ Forrester ◽  
Dominic A Hudson ◽  
Stephen R Turnock
Keyword(s):  
Energy Cost ◽  
Elite Athlete ◽  
Propulsive Efficiency ◽  
Musculoskeletal Modelling ◽  
Fish Locomotion ◽  
The Mean

Analysis of video and speed data is used to evaluate the efficiency of human underwater flykick. The authors show that by coupling Lighthill’s theory of fish locomotion with human musculoskeletal modelling, it is possible to evaluate the effectiveness of the mechanical and hydrodynamic propulsive components of human underwater flykick. This allows the effect of subtle variances in technique to be assessed by measurement of athlete motion alone. This is demonstrated in an experimental case study of an elite athlete performing two different techniques; one more knee-based or thunniform, and the second more undulatory or carangiform/anguilliform. In finding the mean kinematics of each technique, it is first shown that maintaining stroke-by-stroke consistency of technique leads to an increase in propulsive efficiency. It is further demonstrated that in changing technique, an athlete may swim at the same kick rate but have different propulsive efficiency. This demonstrates the need to determine the energy cost in order to evaluate differing techniques. For the sprint athlete in this case study, it was shown to be more effective to swim with a thunniform technique when at higher velocities and a more anguilliform at lower velocities.

scholarly journals Scoping review of the rolling resistance testing methods and factors that impact manual wheelchairs

2021 ◽  
Vol 8 ◽  
pp. 205566832098030
Author(s):  
Joseph Ott ◽  
Jonathan Pearlman
Keyword(s):  
Scoping Review ◽  
Rear Axle ◽  
Rolling Resistance ◽  
Test Methods ◽  
Resistance Testing ◽  
Testing Methods ◽  
Tire Pressure ◽  
Multiple Parameters ◽  
Propulsion Force ◽  
Manual Wheelchairs

Introduction Rolling resistance (RR) is a drag force acting on manual wheelchairs that is associated with increased propulsion force and is linked to secondary disabling conditions of the upper limbs. A scoping review was conducted to understand how RR of manual wheelchairs has been measured and to identify limitations of those test methods and the factors tested. Methods A total of 42 papers were identified and reviewed, and test methods were categorized based on the measurement style of RR, testing level, and if multiple parameters could be tested. Additionally, 34 articles were reviewed for what factors were tested. Results Seven different testing methods categories were identified: drag test, treadmill, motor draw, deceleration, physiological expenditure, ergometer/dynamometer, and robotic test rig. Relevant articles were categorized into testing factor categories: camber, toe, tire type, tire pressure, caster type, mass, mass distribution, and type of surface. Conclusions The variety of testing methods suggests the need for a standardized method that can be used for wheelchair wheel design and selection to reduce RR. It is important to use adjustments, such as a forward rear axle position to mitigate RR as well as using high-pressure pneumatic tires that are properly inflated.

Modern Office Technology Competencies Expected of Office Technology and Management (OTM) Graduate Workers in Delta State.

2019 ◽  
pp. 81-88
Author(s):  
Ozoem Martha ◽  
Chibuike Victoria C. ◽  
Ugwunwoti Emeka P.
Keyword(s):  
Information Processing ◽  
Technology Competencies ◽  
Male And Female ◽  
The World ◽  
Alpha Reliability ◽  
Communication Competencies ◽  
The Mean ◽  
Research Questions ◽  
Level Of Significance ◽  
Descriptive Survey

This study was carried out to determine the modern office technology competencies expected of office technology and management (OTM) graduate workers by supervisors in Delta State. The study was guided by two research questions and two hypotheses tested at 0.05 level of significance. The respondents consisted of 142 supervisors, made up of 74 heads of department and directors of government establishments, and 68 managers and directors of private establishments in the study area. Descriptive survey research design was used to conduct the study and 28 – items questionnaire were used to collect data from respondents. The instrument was validated by three experts and had a Cronbach Alpha reliability coefficient of 0.77. Means with standard deviations were used to answer the research questions, while t-test was used to test the null hypotheses. The extent of supervisor‟s expectations of information processing competencies did not differ significantly based on the mean ratings of male and female supervisors of OTM graduates in government and private establishments. The findings also revealed that supervisors expect much information processing and communication competencies from the OTM graduate workers. Based on the findings and the implications, it was recommended among others that, curriculum planners, business and OTM education lecturers should ensure that the competencies required for modern office technologies are entrenched and taught in the institutions to prepare the OTM graduates for the world of work.

scholarly journals Factors Influencing Smallholder Crop Diversification: A Case Study of Manicaland and Masvingo Provinces in Zimbabwe

2016 ◽  
Vol 3 (2) ◽  
pp. 1 ◽  
Author(s):  
Lighton Dube
Keyword(s):  
Smallholder Farmers ◽  
Diversity Index ◽  
Tobit Model ◽  
Crop Diversification ◽  
Factors Associated ◽  
Head Of Household ◽  
The Mean ◽  
Female Headed Households ◽  
Extension Support

<p>This study analyzes the degree of crop diversification and factors associated with crop diversification among 479 smallholder farmers in Manicaland and Masvingo provinces of Zimbabwe. The Herfindahl index used to estimate diversification, while the Tobit model evaluated factors associated with crop diversification.  The mean crop diversity index is 0.54. On average households in Nyanga and Bikita are the most diversified with indices of 0.48 and 0.49 respectively. The most specialized households are in Mutasa and Chiredzi with indices of 0.62. An analysis by gender shows that male headed households are slightly more diversified than female headed households. The Tobit model indicates that gender of head of household, education, number of livestock units, access to irrigation, membership to a farmers group, access to markets, farming experience, farms on flat terrain, farmer to farm extension, routine extension, agro-ecological zone and household income are significant contributors to increasing crop diversification. In turn, crop specialization is significantly associated with off-farm employment, soil fertility, farmers who are happy with extension contacts per year, farmers trained using the farmer field school approach and farmers who receive NGO extension support.</p>

The Study of Fuel-Saving Technology of GSI

2014 ◽  
Vol 1070-1072 ◽  
pp. 392-397
Author(s):  
Jun Hui Xu ◽  
Ming Qiu Gao ◽  
Ji Qiang Gao ◽  
Xiang Bao
Keyword(s):  
Fuel Consumption ◽  
Fuel Economy ◽  
Rolling Resistance ◽  
Fuel Saving ◽  
Pressure Monitoring ◽  
Tire Pressure ◽  
Engine Efficiency ◽  
Tire Pressure Monitoring System ◽  
The Eu

In the background of the main technologies of fuel economy in automobiles developed to a certain stage, it is necessary to reduce fuel consumption and increase the engine efficiency by developing other auxiliary technologies such as improving the ratio of pure energy drive, low rolling resistance tires, tire pressure monitoring system and gear shift indicators (GSI). This article introduces the principle of GSI, analyses how GSI works in improving engine efficiency, and then evaluates the method for determination of the relative saving rate of fuel consumption, which method was introduced in the EU regulation EC No. 65/2012.

scholarly journals Heavy Metals in Water and Sediment: A Case Study of Tembi River

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Saeed Shanbehzadeh ◽  
Marzieh Vahid Dastjerdi ◽  
Akbar Hassanzadeh ◽  
Toba Kiyanizadeh
Keyword(s):  
Heavy Metals ◽  
Drinking Water ◽  
Average Concentration ◽  
Agricultural Water ◽  
Water And Sediment ◽  
The Mean ◽  
Mean Concentration ◽  
Cu And Zn ◽  
Standard Range

This study was carried out to examine heavy metals concentration in water and sediment of upstream and downstream of the entry of the sewage to the Tembi River, Iran. Samples were collected from upstream and downstream and were analyzed for Cd, Cr, Cu, Fe, Pb, Ni, and Zn by atomic absorption spectrophotometer. The results indicated that the average concentration of the metals in water and sediment on downstream was more than that of upstream. The comparison of the mean concentrations of heavy metals in water of the Tembi River with drinking water standards and those in the water used for agriculture suggests that the mean concentration of Cu and Zn lies within the standard range for drinking water and the mean concentration of Mn, Zn, and Pb lies within the standard range of agricultural water. The highest average concentration on downstream for Pb in water and for Mn in sediment was 1.95 and 820.5 ppm, respectively. Also, the lowest average concentration on upstream was identified for Cd in water and sediment 0.07 and 10 ppm, respectively. With regard to the results, it gets clear that using the water for recreational purposes, washing, and fishing is detrimental to human health and the environment.

Estimates of the energy required for maintenance by adult sheep 2. Grazing sheep

1963 ◽  
Vol 5 (1) ◽  
pp. 11-16 ◽  
Author(s):  
J. P. Langlands ◽  
J. L. Corbett ◽  
I. McDonald ◽  
G. W. Reid
Keyword(s):  
Organic Matter ◽  
Energy Cost ◽  
Functional Relationship ◽  
Adult Sheep ◽  
Maintenance Requirement ◽  
Digestible Organic Matter ◽  
Faecal Nitrogen ◽  
Grazing Period ◽  
The Mean ◽  
Maintenance Requirements

SUMMARYThe mean daily digestible organic matter intake (D) of each of 47 adult sheep during a grazing period of mean length 48 days was estimated by the chromium sesquioxide/faecal nitrogen technique. Mean live-weights (W) and mean daily weight gains (G) were also measured.The regression of D on W and G, and the underlying or functional relationship between D, W and G were both estimated. From the underlying relationship, the preferred equation, the maintenance requirement of a 100 lb. sheep at pasture is estimated to be 1·02 lb. digestible organic matter daily. This value is 24% higher than the corresponding value for housed sheep obtained previously by us.This result is compared with other estimates of the energy cost of grazing and it is concluded that further work is needed in order to define those circumstances which elevate the maintenance requirements of grazing animals.

scholarly journals Illusory Depth Based on Interactions Between Fluorescent and Conventional Colours: A Case Study on Frank Stella’s Irregular Polygons Paintings

2018 ◽  
Vol 6 (2-3) ◽  
pp. 116-150
Author(s):  
Stefanie De Winter ◽  
Pieter Moors ◽  
Hilde Van Gelder ◽  
Johan Wagemans
Keyword(s):  
Contrast Effects ◽  
Depth Effect ◽  
Historical Significance ◽  
Art Historians ◽  
Correct Reading ◽  
The Subject ◽  
The Mean

Although Frank Stella intended to create flat, illusion-less Irregular Polygons paintings, it is not uncommon to experience the illusion of colour depth, based on the interaction between their fluorescent and conventional colours. Some critics praised these artworks’ flatness, while others described odd depth experiences that they categorised as a new kind of illusion. In order to provide a correct reading of these works and to reassess their art historical significance, a scientific case study regarding this colour-depth effect imposes itself. This article discusses an experiment in which we determined whether twenty artists, twenty art historians and twenty laypeople experienced fluorescent colours as protruding, receding or flat in combination with conventional colours. We additionally looked at whether they still perceived colour depth when all fluorescent colours were replaced with their conventional variants. All participants observed fifteen designs, which they had to rate according to the perceived depth of each coloured region with a number between −3 (strongly receding) and +3 (strongly protruding). The results revealed that most participants experience fluorescent regions as strongly protruding, unlike all conventional colours, which were rated as much less protruding. When a fluorescent colour was swapped with a conventional variant, all participants experienced significantly less depth. The differences between the subject groups were statistically negligible when looking at the mean depth ratings for both colour types. However, we discovered that artists experienced more contrast effects, as they gave different ratings to different panels (of identical colour and shape) in the same design, depending on their position.

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