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The improvement in grinding of inlet engine valves by the adoption of the most effective cuting fluid type

Da Silva, Eraldo Jannone; Bianchi, Eduardo Carlos; De Aguiar, Paulo Robero; Catai, Rodrigo Eduardo
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência
Português
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369.54324%
In this paper is presented an experimental research in which the grinding of seating surfaces of inlet engine valves was improved by the adoption of the most effective cutting fluid type, matching the new requirements of cutting fluid application. Four different types of cutting fluids (straight oil and three different types of soluble oils) were analyzed. As qualitative and quantitative evaluation parameters of the performance of the cutting fluids, the roughness, the grinding wheel wear, the cutting force and the workpiece residual stress were determined. As a conclusion, the straight oil was the cutting fluid that presented the best results in all of the parameters analyzed. Copyright © 2000 Society of Automotive Engineers, Inc.

Effects of traffic loading on portuguese and brazilian pavements performance

Fernandes Junior, José Leomar; Pais, Jorge C.; Pereira, Paulo A. A.
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em //2006 Português
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473.7855%
This work investigated the effects of traffic loading on the performance of Portuguese and Brazilian pavements, aiming to contribute to a better technical regulation of heavy vehicles and cost allocation related to the pavement deterioration. Among the traffic loading factors, this work considered axle load, axle type, tire inflation pressure, and wheel type. Six pavement structures were analyzed where three of them are representative of Portuguese pavements, and three are representative of Brazilian pavements. It was performed a linear-elastic mechanistic analysis to determine two structural responses: horizontal tensile strain at the bottom of the asphalt layer and vertical compressive strain at the top of subgrade, associated to the most important pavement distresses in Portugal and Brazil, respectively fatigue cracking and rutting. With the structural responses it was calculated load equivalence factors, which represent the relative effect of each loading condition and allow the analysis of Portuguese and Brazilian pavement design methods and regulations.

Software and Hardware control of a hybrid robot for switching between leg-type and wheel-type modes

Botelho,Wagner Tanaka; Okada,Tokuji; Mahmoud,Abeer; Shimizu,Toshimi
Fonte: Sociedade Brasileira de Automática Publicador: Sociedade Brasileira de Automática
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2011 Português
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One of the objectives of the paper is to describe the hybrid robot PEOPLER-II (Perpendicularly Oriented Planetary Legged Robot) with regard to switching between leg-type and wheel-type. Our robot has an easier design and control system than other hybrid robots. The software and hardware control in the process of performing five robot tasks are considered. These are the walking, rolling, switching, turning and spinning. In the switching task, we show the control method based on minimization of total energycost. Also, the hardware components and their interconnections are described. The graphical user interfaces utilized in the simulation and experiment are demonstrated. The walking, rolling and the switching without reverse rotation and arm motion are verified in simulation and with real robot, in addition to turning and spinning.

Analysis of the cutting fluid influence on the deep grinding process with a CBN grinding wheel

Fusse,Ronaldo Yoshinobu; França,Thiago Valle; Catai,Rodrigo Eduardo; Silva,Leonardo Roberto da; Aguiar,Paulo Roberto de; Bianchi,Eduardo Carlos
Fonte: ABM, ABC, ABPol Publicador: ABM, ABC, ABPol
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2004 Português
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384.39617%
The application of cutting fluid in a deep grinding process is becoming more and more important, mainly where the cutting fluids are used as an "external" agent to the grinding conditions. The role of the fluid in grinding operations is in refrigeration of the workpiece, removal of the shavings, lubrication of the grinding zone, and refrigeration and cleaning of the wheel. The efficiency of a cutting fluid will depend mainly of the type of fluid that will be used. In this work, the influences of the type of cutting fluid used in a deep grinding process of the steel VC131 using CBN grinding wheel are analyzed. Three different types of cutting fluids were used: a vegetable emulsion, a synthetic solution and a integral oil. The variables analyzed during and after the grinding process were the grinding force, the superficial roughness, the acoustic emission (EA), the temperature of the piece and the G ratio (relationship between the volume of material removed from the piece and the volume worn off the grinding wheel). The integral oil showed the best performance relative to the following output variables: EA, cutting force and G ratio. The vegetal emulsion was the fluid that best dissipated heat from the cutting region.

Responding for sucrose and wheel-running reinforcement: effects of sucrose concentration and wheel-running reinforcer duration.

Belke, Terry W; Hancock, Stephanie D
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /03/2003 Português
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276.33582%
Six male albino rats were placed in running wheels and exposed to a fixed-interval 30-s schedule of lever pressing that produced either a drop of sucrose solution or the opportunity to run for a fixed duration as reinforcers. Each reinforcer type was signaled by a different stimulus. In Experiment 1, the duration of running was held constant at 15 s while the concentration of sucrose solution was varied across values of 0, 2.5. 5, 10, and 15%. As concentration decreased, postreinforcement pause duration increased and local rates decreased in the presence of the stimulus signaling sucrose. Consequently, the difference between responding in the presence of stimuli signaling wheel-running and sucrose reinforcers diminished, and at 2.5%, response functions for the two reinforcers were similar. In Experiment 2, the concentration of sucrose solution was held constant at 15% while the duration of the opportunity to run was first varied across values of 15, 45, and 90 s then subsequently across values of 5, 10, and 15 s. As run duration increased, postreinforcement pause duration in the presence of the wheel-running stimulus increased and local rates increased then decreased. In summary, inhibitory aftereffects of previous reinforcers occurred when both sucrose concentration and run duration varied; changes in responding were attributable to changes in the excitatory value of the stimuli signaling the two reinforcers.

Changes in visceral adipose tissue mitochondrial content with type 2 diabetes and daily voluntary wheel running in OLETF rats

Laye, Matthew J; Rector, R Scott; Warner, Shana O; Naples, Scott P; Perretta, Aspen L; Uptergrove, Grace M; Laughlin, M Harold; Thyfault, John P; Booth, Frank W; Ibdah, Jamal A
Fonte: Blackwell Science Inc Publicador: Blackwell Science Inc
Tipo: Artigo de Revista Científica
Português
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274.8803%
Using the hyperphagic, obese, Otsuka Long–Evans Tokushima Fatty (OLETF) rat, we sought to determine if progression to type 2 diabetes alters visceral white adipose tissue (WAT) mitochondrial content and if these changes are modified through prevention of type 2 diabetes with daily exercise. At 4 weeks of age, OLETF rats began voluntary wheel running (OLETF-EX) while additional OLETF rats (OLETF-SED) and Long–Evans Tokushima Otsuka (LETO-SED) rats served as obese and lean sedentary controls, respectively, for 13, 20 and 40 weeks of age (n= 6–8 for each group at each age). OLETF-SED animals displayed insulin resistance at 13 and 20 weeks and type 2 diabetes by 40 weeks. OLETF-SED animals gained significantly (P < 0.001) more weight and omental fat mass compared with OLETF-EX and LETO-SED. Markers of WAT mitochondrial protein content (cytochrome c, COXIV-subunit I, and citrate synthase activity) significantly increased (P < 0.05) from 13 to 40 weeks in the LETO-SED, but were significantly attenuated in the OLETF-SED rats. Daily exercise normalized WAT cytochrome c and COXIV-subunit I protein content in the OLETF-EX to the healthy LETO-SED animals. In conclusion, increases in omental WAT mitochondrial content between 20 and 40 weeks of age in LETO control animals are attenuated in the hyperphagic...

Superficial Type of Multiple Basal Cell Carcinomas: Detailed Comparative Study of Its Dermoscopic and Histopathological Findings

Hirofuji, Akiko; Takiguchi, Kojiro; Nakamura, Koichiro; Kuramochi, Akira; Tsuchida, Tetsuya; Arai, Eiichi; Shimizu, Michio
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
Português
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We investigated in detail the dermoscopic and histopathological findings in a case of a superficial type of multiple basal cell carcinomas (BCCs). These multiple lesions (occurring in the chest, neck, and back) showed three different findings, respectively. Dermoscopy of the erythematous and brown-colored patch on the anterior chest showed spoke wheel areas, and the histopathological cross-section revealed vertical spoke wheel structures. In the black- and brown-colored patch at the neck, the dermatoscopy showed a maple leaf-like structure, which was in accordance with the strengthening of the histological lateral connection of the lesion. The brown-colored patch of the lateral back histologically showed irregularly enlarged spoke wheel-like areas with peripheral increased melanin pigments, which correlated with the dark black color of dermoscopic maple leaf-like areas. The vertical spoke wheel areas by dermatoscopy revealed a horizontal spoke wheel structure by histopathology.

Voluntary scheduled exercise alters diurnal rhythms of behaviour, physiology and gene expression in wild-type and vasoactive intestinal peptide-deficient mice

Schroeder, Analyne M; Truong, Danny; Loh, Dawn H; Jordan, Maria C; Roos, Kenneth P; Colwell, Christopher S
Fonte: Blackwell Science Inc Publicador: Blackwell Science Inc
Tipo: Artigo de Revista Científica
Português
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281.34941%
The circadian system co-ordinates the temporal patterning of behaviour and many underlying biological processes. In some cases, the regulated outputs of the circadian system, such as activity, may be able to feed back to alter core clock processes. In our studies, we used four wheel-access conditions (no access; free access; early night; and late night) to manipulate the duration and timing of activity while under the influence of a light–dark cycle. In wild-type mice, scheduled wheel access was able to increase ambulatory activity, inducing a level of exercise driven at various phases of the light–dark cycle. Scheduled exercise also manipulated the magnitude and phasing of the circadian-regulated outputs of heart rate and body temperature. At a molecular level, the phasing and amplitude of PER2::LUCIFERASE (PER2::LUC) expression rhythms in the SCN and peripheral tissues of Per2::Luc knockin mice were altered by scheduled exercise. We then tested whether scheduled wheel access could improve deficits observed in vasointestinal polypeptide-deficient mice under the influence of a light–dark cycle. We found that scheduled wheel access during the late night improved many of the behavioural, physiological and molecular deficits previously described in vasointestinal polypeptide-deficient mice. Our results raise the possibility that scheduled exercise could be used as a tool to modulate daily rhythms and...

Moderate voluntary exercise attenuates the metabolic syndrome in melanocortin-4 receptor-deficient rats showing central dopaminergic dysregulation☆

Obici, Silvana; Magrisso, I. Jack; Ghazarian, Armen S.; Shirazian, Alireza; Miller, Jonas R.; Loyd, Christine M.; Begg, Denovan P.; Krawczewski Carhuatanta, Kimberly A.; Haas, Michael K.; Davis, Jon F.; Woods, Stephen C.; Sandoval, Darleen A.; Seeley, Ran
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Português
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Objective: Melanocortin-4 receptors (MC4Rs) are highly expressed by dopamine-secreting neurons of the mesolimbic tract, but their functional role has not been fully resolved. Voluntary wheel running (VWR) induces adaptations in the mesolimbic dopamine system and has a myriad of long-term beneficial effects on health. In the present experiments we asked whether MC4R function regulates the effects of VWR, and whether VWR ameliorates MC4R-associated symptoms of the metabolic syndrome. Methods: Electrically evoked dopamine release was measured in slice preparations from sedentary wild-type and MC4R-deficient Mc4rK314X (HOM) rats. VWR was assessed in wild-type and HOM rats, and in MC4R-deficient loxTBMc4r mice, wild-type mice body weight-matched to loxTBMc4r mice, and wild-type mice with intracerebroventricular administration of the MC4R antagonist SHU9119. Mesolimbic dopamine system function (gene/protein expression) and metabolic parameters were examined in wheel-running and sedentary wild-type and HOM rats. Results: Sedentary obese HOM rats had increased electrically evoked dopamine release in several ventral tegmental area (VTA) projection sites compared to wild-type controls. MC4R loss-of-function decreased VWR, and this was partially independent of body weight. HOM wheel-runners had attenuated markers of intracellular D1-type dopamine receptor signaling despite increased dopamine flux in the VTA. VWR increased and decreased ΔFosB levels in the nucleus accumbens (NAc) of wild-type and HOM runners...

Identification of a physiological role for leptin in the regulation of ambulatory activity and wheel running in mice

Morton, Gregory J.; Kaiyala, Karl J.; Fisher, Jonathan D.; Ogimoto, Kayoko; Schwartz, Michael W.; Wisse, Brent E.
Fonte: American Physiological Society Publicador: American Physiological Society
Tipo: Artigo de Revista Científica
Português
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292.50262%
Mechanisms regulating spontaneous physical activity remain poorly characterized despite evidence of influential genetic and acquired factors. We evaluated ambulatory activity and wheel running in leptin-deficient ob/ob mice and in wild-type mice rendered hypoleptinemic by fasting in both the presence and absence of subcutaneous leptin administration. In ob/ob mice, leptin treatment to plasma levels characteristic of wild-type mice acutely increased both ambulatory activity (by 4,000 ± 200 beam breaks/dark cycle, P < 0.05) and total energy expenditure (TEE; by 0.11 ± 0.01 kcal/h during the dark cycle, P < 0.05) in a dose-dependent manner and acutely increased wheel running (+350%, P < 0.05). Fasting potently increased ambulatory activity and wheel running in wild-type mice (AA: +25%, P < 0.05; wheel running: +80%, P < 0.05), and the effect of fasting was more pronounced in ob/ob mice (AA: +400%, P < 0.05; wheel running: +1,600%, P < 0.05). However, unlike what occurred in ad libitum-fed ob/ob mice, physiological leptin replacement attenuated or prevented fasting-induced increases of ambulatory activity and wheel running in both wild-type and ob/ob mice. Thus, plasma leptin is a physiological regulator of spontaneous physical activity...

Muscle injury, cross-sectional area and fibre type distribution in mouse soleus after intermittent wheel-running.

Wernig, A; Irintchev, A; Weisshaupt, P
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /09/1990 Português
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1. It was previously noticed that mouse soleus, but not extensor digitorum longus (EDL) muscles, suffer fibre damage at the onset of voluntary wheel-running without further injuries thereafter. 2. In CBA/J mice trained continuously for 5 months and rested for periods of 1, 2, 3, 4 and 5 weeks acute muscle damage was found in soleus 7 days after the resumption of wheel-running. On single cross-sections damage was present on average in 8.7 +/- 3.5% (mean +/- S.D., n = 15) of the fibres, but only in 0.47 +/- 0.21% (n = 9) and 1.3 +/- 1.1% (n = 4) in control animals rested for 0-6 weeks after continuous running or in untrained controls. 3. Repeated muscle damage occurred when mice exercised for 4 days at intervals of 21-25 days, and after thirteen running episodes within 12 months marked changes in soleus, but not EDL muscles, were present. In cross-sections the total number of muscle fibre profiles was significantly larger in soleus of intermittent runners (768 +/- 68, n = 6; P less than 0.05), compared to continuous runners (676 +/- 54, n = 3) and sedentary animals (683 +/- 33, n = 4). This is probably due to incomplete repair which results in 'split fibres'. 4. At the same time total muscle fibre cross-sectional area was significantly elevated in intermittent runners (P less than 0.05)...

Unusual Conformation of a Dinuclear Paddle Wheel Copper(II) Complex. Synthesis, Structural Characterization and EPR Studies

Madrid, Rosa; Venegas Yazigi, Diego; Santana, Ricardo C.; Vega, Andrés; Paredes García, Verónica; Spodine Spiridonova, Evgenia
Fonte: American Chemical Society Publicador: American Chemical Society
Tipo: Artículo de revista
Português
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Artículos de publicación ISI; An unusual and unique conformation of a paddle wheel type binuclear copper(II) complex containing acetate and acetamido ligands, {Cu2(μ2-O2CCH3)4}(OCNH2CH3) (1), was obtained by solvothermal synthesis. The structural characterization of this compound shows that the apical (acetamido) ligands are disposed at a 62° dihedral angle, generating a special conformation as a consequence of the synthetic method used. This conformation has not been reported in other paddle wheel copper(II) tetraacetate compounds. Electron paramagnetic resonance (EPR) spectra of powder samples of (1) were obtained at 9.5 and 33.8 GHz, while single crystal spectra were obtained at 33.8 GHz with a B0 applied in three orthogonal planes. The fit of the single crystal experimental data allowed gave g∥ = 2.345 ± 0.003, and g⊥ = 2.057 ± 0.005. The angular variation of the EPR line allows evaluation of the fine structure of (1), giving D = −0.337 ± 0.002 cm−1 and E = −0.005 ± 0.001 cm−1. The line width angular dependence, used together with the Anderson model and Kubo−Tomita theory, permitted the interdimer interaction to be evaluated as |J′| = (0.051 ± 0.002) cm−1. Using the powder spectral temperature dependence it was possible to evaluate the intradinuclear exchange coupling constan J0 as −101 ± 2 cm−1...

Designing a Miniature Wheel Arrangement for Mobile Robot Platforms

Kayani, Saheeb Ahmed
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
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In this research report details of design of a miniature wheel arrangement are presented. This miniature wheel arrangement is essentially a direction control mechanism intended for use on a mobile robot platform or base. The design is a specific one employing a stepper motor as actuator and as described can only be used on a certain type of wheeled robots. However, as a basic steering control element, more than one of these miniature wheel arrangements can be grouped together to implement more elaborate and intelligent direction control schemes on varying configurations of wheeled mobile robot platforms.; Comment: Final published version, hardcopy available from technical library of NUST College of E&ME, Rawalpindi, Pakistan on request

Kepler White Paper: Asteroseismology of Solar-Like Oscillators in a 2-Wheel Mission

Chaplin, W. J; Kjeldsen, H.; Christensen-Dalsgaard, J.; Gilliland, R. L.; Kawaler, S. D.; Basu, S.; De Ridder, J.; Huber, D.; Arentoft, T.; Schou, J.; Garcia, R. A.; Metcalfe, T. S.; Brogaard, K.; Campante, T. L.; Elsworth, Y.; Miglio, A.; Appourchaux, T.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 03/09/2013 Português
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We comment on the potential for continuing asteroseismology of solar-type and red-giant stars in a 2-wheel Kepler Mission. Our main conclusion is that by targeting stars in the ecliptic it should be possible to perform high-quality asteroseismology, as long as favorable scenarios for 2-wheel pointing performance are met. Targeting the ecliptic would potentially facilitate unique science that was not possible in the nominal Mission, notably from the study of clusters that are significantly brighter than those in the Kepler field. Our conclusions are based on predictions of 2-wheel observations made by a space photometry simulator, with information provided by the Kepler Project used as input to describe the degraded pointing scenarios. We find that elevated levels of frequency-dependent noise, consistent with the above scenarios, would have a significant negative impact on our ability to continue asteroseismic studies of solar-like oscillators in the Kepler field. However, the situation may be much more optimistic for observations in the ecliptic, provided that pointing resets of the spacecraft during regular desaturations of the two functioning reaction wheels are accurate at the < 1 arcsec level. This would make it possible to apply a post-hoc analysis that would recover most of the lost photometric precision. Without this post-hoc correction---and the accurate re-pointing it requires---the performance would probably be as poor as in the Kepler-field case. Critical to our conclusions for both fields is the assumed level of pointing noise (in the short-term jitter and the longer-term drift). We suggest that further tests will be needed to clarify our results once more detail and data on the expected pointing performance becomes available...

Wheel Random Apollonian Graphs

Giacomelli, Piero
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 20/11/2010 Português
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In this paper a subset of High-Dimensional Random Apollonian networks, that we called Wheel Random Apollonian Graphs (WRAG), is considered. We show how to generate a Wheel Random Apollonian Graph from a wheel graph. We analyse some basic graph properties like vertices and edges cardinality, some question concerning cycles and the chromaticity in such type of graphs, we suggest further work on this type of graphs.

A study on the wheel-rail interaction at switch points to reduce derailments in turnouts

Ozturk, Samet
Fonte: University of Delaware Publicador: University of Delaware
Tipo: Tese de Doutorado
Português
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287.17426%
Zarembski, Allan M.; Railroad transportation has been very important for human being for last two centuries. Although it is known as one of the safest forms of land transportation systems; mechanical, operational, and human behavioral problems result in a significant number of derailments on US railroads every year. While a collision represents the impact between two trains in any direction, a derailment occurs when a wheel of a car runs off the track. One of the most common derailment cause category is wheel climb derailments. Wheel climb derailments can be results of wheel problems, rail problems and operational problems or combination of these. A significant percentage of the wheel climb derailments occurs at turnouts. Thus, it is vitally important to determine the conditions of switch points before a derailment occurs. In this study, a mechanism for wheel climb derailments has been applied to turnouts by using data taken from an Automated Switch Inspection Vehicle (ASIV). This data was used to conduct a set of wheel climb analysis to determine the critical points through the specific turnouts and the risk of wheel climb derailment. This thesis introduces the background of this methodology, conducts an analysis of collected data...

A model for equivalent axle load factors

Amorim, Sara I.R.; Pais, Jorge C.; Vale, Aline C.; Minhoto, Manuel J.C.
Fonte: Taylor & Francis Publicador: Taylor & Francis
Tipo: Artigo de Revista Científica
Português
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395.45375%
Most design methods for road pavements require the design traffic, based on the transformation of the traffic spectrum, to be calculated into a number of equivalent passages of a standard axle using the equivalent axle load factors. Generally, these factors only consider the type of axle (single, tandem or tridem), but they do not consider the type of wheel on the axles, i.e., single or dual wheel. The type of wheel has an important influence on the calculation of the design traffic. The existing design methods assume that the equivalent axle load factors are valid for all pavement structures and do not consider the thickness and stiffness of the pavement layers. This paper presents the results of the development of a model for the calculation of the equivalent axle load factors considering the type of axle, the type of wheel and the constitution of the pavement. The model was developed based on the tensile strain at the bottom of the asphalt layer that is responsible for bottom-up cracking in asphalt pavement, which is the most widely considered distress mode for flexible road pavements. The work developed in this study also presents the influence of the type of wheel (single and dual) on pavement performance. The results of this work allowed the conclusion that the equivalent axle load factors for single wheels is approximately 10 times greater than for a dual wheel. This work also proposes average values for the equivalent axle load factors. An artificial neural network was developed to calculate the equivalent axle load factors.

Effect of steering wheel acceleration frequency distribution on detection of road type

Berber-Solano,T.P.; Giacomin,J.A.; Ajovalasit,M.
Fonte: Sociedad Mexicana de Ingeniería Mecánica Publicador: Sociedad Mexicana de Ingeniería Mecánica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2013 Português
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389.22277%
A laboratory-based experiment was conducted to evaluate the effect of the vibrational energy distribution on the human detection of road surface type by means of steering wheel vibration. The study used steering wheel tangential direction acceleration time histories which had been measured in a mid-sized European automobile that was driven over three different types of road surface. The steering acceleration stimuli were manipulated by means of digital Butterworth filters which were used to eliminate five selected frequency ranges from the steering wheel vibration spectrum in the interval from 0 to 150 Hz. The experiment was performed in three parts, one for each road surface studied in which a photograph of one of the three road surfaces was shown. The photograph shown was an image approximately similar to what a driver sees of the road during driving. Fifteen test participants were exposed to both unmanipulated and manipulated steering wheel tangential vibration stimuli, and were asked to indicate, by either "yes" or "no", whether the actuated acceleration stimulus was from the road surface whose photograph was shown on the board directly in front of the test bench. The findings suggest that the frequency band from 20 to 60 Hz, which is most often associated with specific resonances of the steering system such as the column and tyres...

The effect of an angle on the impact and flow quantity on output power of an impulse water wheel model

Tyagi,Ram K
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2015 Português
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Nowadays, the world is more focused on hydraulic energy, which scientists have initiated thorough analyses of hydropower resources. The potential of wind power generation is immense. It is an historical source of energy but wind power is not applicable in this case. In India, water can be used for both - as a source of electricity and for irrigation and agricultural use. Impulse type water wheels were employed until flow is accessible. According to available literature, there are three types of water wheels and the application of a particular type of water wheel depends upon the stream of water. In this article, an extremely uncomplicated category impulse water wheel is fabricated. To fabricate this water wheel, little engineering is required. The experimental results obtained indicate that intensity of generated power depends upon the angle of water impact on the turbine blade, height, quantity of water flowing in pipe etc. The aim of this article is to suggest an alternative source of economical and environmentally friendly green energy for a small quantity of fluid flowing. There are various sources of small quantity water such as large society storage tank water, sewer line water, canals water and many more. The construction cost of water wheels is not as much since it does not have an intricate blade profile.

Sulfide-type inclusion morphologies of a Ca-treated hot-rolled wheel steel

Keskinkilic,E
Fonte: Journal of the Southern African Institute of Mining and Metallurgy Publicador: Journal of the Southern African Institute of Mining and Metallurgy
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2011 Português
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SYNOPSIS In this study, sulfide-type inclusion morphologies of a Ca-treated hot-rolled wheel steel, Grade-X, were investigated. The specimens taken from the hot-rolled products of Grade-X heats were studied. The size and distribution of elongated sulfide inclusions were examined for the heats of different S levels. Elongated sulfide inclusions were either not observed or rarely encountered when ladle analysis S content was below 50 ppm. The size and relative abundance of sulfide inclusions were reported to increase markedly when the S composition was greater than or equal to 70 ppm and the Ca/S ratio was less than 0.50. The effect of Ti addition (0.010-0.020% Ti) on sulfide-type inclusion morphologies was then investigated for heats having a sulfur content higher than 50 ppm. Addition of Ti was found to have a partial effect on decreasing the size of sulfide-type inclusions under real steelmaking conditions.