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Опубліковано: 14 березня 2023

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Статті в журналах з теми "Belt Drive Systems"

1

SZCZYPIŃSKI-SALA, Wojciech, Krzysztof DOBAJ, and Adam KOT. "FRICTIONAL PROBLEMS IN CONTINUOUSLY VARIABLE TRANSMISSION BELT DRIVES." Tribologia, no. 5 (October 31, 2017): 93–100. http://dx.doi.org/10.5604/01.3001.0010.5923.

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The article describes the results of the research carried out on the evaluation of the influence of friction pairs (rubber belt – belt pulley in belt drive) on the ability to transmit power. In order to determine the characteristics of the belt drive operation, measurements were made on a real belt drive from the drive train of a light two-wheeled vehicle. The measurement was carried out in conditions of changes in the dynamic load. The measurements of the belt slip on the belt pulley within the whole range of the changes of gear ratios and angular speed of the engine were made. During the tests, belts made from various rubber mixtures were compared. The values of the friction coefficients between the surface of belts and the belt pulley were measured. Model analyses of the impact of belt slip on the wheel related to the temperature of Belt drive elements were also made. Generally, one can ascertain that, in belt drive systems, power losses are a combination of speed losses and torque losses. The increase in the efficiency of belt drives is possible by decreasing power losses. It is possible to obtain the high performance of continuously variable transmission belt drives with a V- belt solely with the proper choice of the design parameters, which is possible only after the exact recognition of the operational characteristics unique to this class of belt drive systems.
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2

Beikmann, R. S., N. C. Perkins, and A. G. Ulsoy. "Free Vibration of Serpentine Belt Drive Systems." Journal of Vibration and Acoustics 118, no. 3 (July 1, 1996): 406–13. http://dx.doi.org/10.1115/1.2888197.

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Анотація:
The vibration of an automotive serpentine belt drive system greatly affects the perceived quality and the reliability of the system. Accessory drives with unfavorable vibration characteristics transmit excessive noise and vibration to other vehicle structures, to the vehicle occupants, and may also promote the fatigue and failure of system components. Moreover, these characteristics are a consequence of decisions made early on in the design and arrangement of the accessory drive system. The present paper focuses on fundamental modeling issues that are central to predicting accessory drive vibration. To this end, a prototypical drive is evaluated, which is composed of a driven pulley, a driving pulley, and a dynamic tensioner. The coupled equations of free response governing the discrete and continuous elements are presented herein. A closed-form solution method is used to evaluate the natural frequencies and modeshapes. Attention focuses on a key linear mechanism that couples tensioner arm rotation and transverse vibration of the adjacent belt spans. Modal tests on an experimental drive confirm the theoretical predictions.
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3

Ulsoy, A. G., J. E. Whitesell, and M. D. Hooven. "Design of Belt-Tensioner Systems for Dynamic Stability." Journal of Vibration and Acoustics 107, no. 3 (July 1, 1985): 282–90. http://dx.doi.org/10.1115/1.3269258.

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Анотація:
Belt drive systems are an effective means for power transmission which offer the advantages of light weight, low cost, quietness, and efficiency. Recently in automotive applications there has been a trend to power several accessories with a single drive belt in order to reduce overall vehicle size and weight. Since these belts are typically longer than conventional belts, a tensioner component is added to maintain acceptable belt tension levels. In this paper we describe several potential instability mechanisms for belt-tensioner systems, and present a design methodology to ensure good dynamic performance of such systems. A mathematical model of the belt-tensioner system, and numerical solution methods, are utilized to develop a computer-aided design procedure. Numerical results, and confirming experimental data, are presented for a particular automotive belt-tensioner system.
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4

Leamy, Michael J., and Tamer M. Wasfy. "Transient and Steady-State Dynamic Finite Element Modeling of Belt-Drives." Journal of Dynamic Systems, Measurement, and Control 124, no. 4 (December 1, 2002): 575–81. http://dx.doi.org/10.1115/1.1513793.

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Анотація:
In this study, a dynamic finite element model is developed for pulley belt-drive systems and is employed to determine the transient and steady-state response of a prototypical belt-drive. The belt is modeled using standard truss elements, while the pulleys are modeled using rotating circular constraints, for which the driver pulley’s angular velocity is prescribed. Frictional contact between the pulleys and the belt is modeled using a penalty formulation with frictional contact governed by a Coulomb-like tri-linear friction law. One-way clutch elements are modeled using a proportional torque law supporting torque transmission in a single direction. The dynamic response of the drive is then studied by incorporating the model into an explicit finite element code, which can maintain time-accuracy for large rotations and for long simulation times. The finite element solution is validated through comparison to an exact analytical solution of a steadily-rotating, two-pulley drive. Several response quantities are compared, including the normal and tangential (friction) force distributions between the pulleys and the belt, the driven pulley angular velocity, and the belt span tensions. Excellent agreement is found. Transient response results for a second belt-drive example involving a one-way clutch are used to demonstrate the utility and flexibility of the finite element solution approach.
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Feng, Xiao, Wen-Bin Shangguan, Jianxiang Deng, Xingjian Jing, and Waizuddin Ahmed. "Modelling of the rotational vibrations of the engine front-end accessory drive system: a generic method." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 231, no. 13 (January 23, 2017): 1780–95. http://dx.doi.org/10.1177/0954407016685966.

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Анотація:
To investigate the rotation vibration dynamics of the pulleys and the tension arms, and to estimate the vibrations of the belts and the slip ratio between the belt and the pulleys in the engine front-end accessory drive systems, a systematic modelling and analytical method is proposed for engine front-end accessory drive systems; this can be used for modelling engine front-end accessory drive systems with different layouts and different numbers of tensioners, including automatic and fixed tensioners. In the modelling, the rotational pulleys are classified as fixed-axis pulleys and moveable-axis pulleys (such as the pulley in the tensioner). Moreover, the belt spans are classified as the belt spans between the two fixed pulleys, and the belt spans adjacent to the pulley of a tensioner. The equations of motion for each type of pulley and the tension calculation equations for each type of belt span are developed. In this way, the equations of motion for all the pulleys and the tensioner arms can be obtained easily, irrespective of the layout of the tensioners. To obtain the dynamic rotational vibration responses of an engine front-end accessory drive system by the conventional Runge–Kutta method, high-efficiency algorithms or methods are also proposed for calculating the tangent-point coordinates between a belt and the adjacent pulleys and the belt length of the contact arc on one pulley. The proposed modelling and analysis methods are validated by modelling different layouts of the engine front-end accessory drive systems with different types and numbers of tensioners, and also by comparisons between the calculated dynamic vibration responses of the pulleys and the belts and the real experimental data.
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6

Goncharov, K. A. "Conceptual solutions for control systems of differential tensioners for belt conveyors." Nauchno-tekhnicheskiy vestnik Bryanskogo gosudarstvennogo universiteta 7, no. 4 (December 25, 2021): 316–27. http://dx.doi.org/10.22281/2413-9920-2021-07-04-316-327.

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Анотація:
Differential tensioning devices for belt conveyors in general and intermediate drives of extended conveyors in the form of closed traction loops are a new type of automatic tensioning devices that differ from other known designs by the presence of a stepwise discrete belt tension control system with separation of compensation functions for belt stretching under load and control of its tension during the operation of the conveyor in order to create optimal modes of belt loading. The article analyzes the well-known and practical concepts of belt conveyor control systems in general. The possibility of controlling the traction force realized by the intermediate belt drive by controlling the tension of the traction and load-carrying belts is shown. On the basis of the analysis, conceptual solutions for control systems for differential tensioning devices of belt conveyors are proposed with the possibility of both autonomous use and application in the structure of an integrated conveyor control system. Possible structures of linear parts of differential tensioning devices are presented, as well as options for the implementation of executive parts that directly move tensioning elements.
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7

Hwang, S. J., N. C. Perkins, A. G. Ulsoy, and R. J. Meckstroth. "Rotational Response and Slip Prediction of Serpentine Belt Drive Systems." Journal of Vibration and Acoustics 116, no. 1 (January 1, 1994): 71–78. http://dx.doi.org/10.1115/1.2930400.

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Анотація:
A nonlinear model is developed which describes the rotational response of automotive serpentine belt drive systems. Serpentine drives utilize a single (long) belt to drive all engine accessories from the crankshaft. An equilibrium analysis leads to a closed-form procedure for determining steady-state tensions in each belt span. The equations of motion are linearized about the equilibrium state and rotational mode vibration characteristics are determined from the eigenvalue problem governing free response. Numerical solutions of the nonlinear equations of motion indicate that, under certain engine operating conditions, the dynamic tension fluctuations may be sufficient to cause the belt to slip on particular accessory pulleys. Experimental measurements of dynamic response are in good agreement with theoretical results and confirm theoretical predictions of system vibration, tension fluctuations, and slip.
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8

Bajda, Mirosław, and Monika Hardygóra. "Analysis of the Influence of the Type of Belt on the Energy Consumption of Transport Processes in a Belt Conveyor." Energies 14, no. 19 (September 28, 2021): 6180. http://dx.doi.org/10.3390/en14196180.

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Анотація:
Results of tests into the energy-efficiency of belt conveyor transportation systems indicate that the energy consumption of their drive mechanisms can be limited by lowering the main resistances in the conveyor. The main component of these resistances is represented by belt indentation rolling resistance. Limiting its value will allow a reduction in the amount of energy consumed by the drive mechanisms. This article presents a test rig which enables uncomplicated evaluations of such rolling resistances. It also presents the results of comparative tests performed for five steel-cord conveyor belts. The tests involved a standard belt, a refurbished belt and three energy-saving belts. As temperature significantly influences the values of belt indentation rolling resistance, the tests were performed in both positive and negative temperatures. The results indicate that when compared with the standard belt, the refurbished and the energy-efficient belts generate higher and lower indentation rolling resistances, respectively. In order to demonstrate practical advantages resulting from the use of energy-saving belts, this article also includes calculations of the power demand of a conveyor drive mechanism during one calendar year, as measured on a belt conveyor operated in a mine. The replacement of a standard belt with a refurbished belt generates a power demand higher by 4.8%, and with an energy-efficient belt—lower by 15.3%.
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9

Tonoli, Andrea, Nicola Amati, and Enrico Zenerino. "Dynamic Modeling of Belt Drive Systems: Effects of the Shear Deformations." Journal of Vibration and Acoustics 128, no. 5 (February 3, 2006): 555–67. http://dx.doi.org/10.1115/1.2202153.

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Анотація:
Multiribbed serpentine belt drive systems are widely adopted in accessory drive automotive applications due to the better performances relative to the flat or V-belt drives. Nevertheless, they can generate unwanted noise and vibration which may affect the correct functionality and the fatigue life of the belt and of the other components of the transmission. The aim of the paper is to analyze the effect of the shear deflection in the rubber layer between the pulley and the belt fibers on the rotational dynamic behavior of the transmission. To this end the Firbank’s model has been extended to cover the case of small amplitude vibrations about mean rotational speeds. The model evidences that the shear deflection can be accounted for by an elastic term reacting to the torsional oscillations in series with a viscous term that dominates at constant speed. In addition, the axial deformation of the belt spans are taken into account. The numerical model has been validated by the comparison with the experimental results obtained on an accessory drive transmission including two pulleys and an automatic tensioner. The results show that the first rotational modes of the system are dominated by the shear deflection of the belt.
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10

Beikmann, R. S., N. C. Perkins, and A. G. Ulsoy. "Nonlinear Coupled Vibration Response of Serpentine Belt Drive Systems." Journal of Vibration and Acoustics 118, no. 4 (October 1, 1996): 567–74. http://dx.doi.org/10.1115/1.2888336.

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Анотація:
This theoretical and experimental study identifies a key nonlinear mechanism that promotes strongly coupled dynamics of serpentine belt drive systems. Attention is focused on a prototypical three-pulley system that contains the essential features of automotive serpentine drives having automatic (spring-loaded) tensioners. A theoretical model is presented that describes pulley and tensioner arm rotations, and longitudinal and transverse belt vibration response. A recent investigation demonstrates that infinitesimal belt stretching creates a linear mechanism that couples transverse belt vibration to tensioner arm rotation. Here, it is further demonstrated that finite belt stretching creates a nonlinear mechanism that may lead to strong coupling between pulley/tensioner arm rotation and transverse belt vibration, in the presence of an internal resonance. Theoretical and experimental results confirm the existence of this nonlinear coupling mechanism. In particular, it is shown that very large transverse belt vibrations can result from small resonant torque pulses applied to the crankshaft or accessory pulleys. These large amplitude transverse vibrations are particularly sensitive to seemingly small changes in the rotational mode characteristics.
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Дисертації з теми "Belt Drive Systems"

1

Zhang, Lixin. "Dynamic analysis of viscoelastic serpentine belt drive systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0021/NQ45747.pdf.

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2

Yang, Xuedong. "Modeling and control of two-axis belt-drive gantry robots." Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/13061.

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3

Masaki, Mukalu Sandro. "A cost-effective design approach for multiple drive belt conveyor systems." Diss., University of Pretoria, 2005. http://hdl.handle.net/2263/66217.

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Анотація:
Multiple drive belt conveyors are being increasingly incorporated in mining plans worldwide because of their high economic performance and the ease of moving these installations around, especially in underground mines. A typical modern multi-drive conveyor system consists of one or more intermediate drive stations positioned along the upper stretch of the conveyor and a single drive station situated in the lower stretch. Despite the acknowledged cost saving potential of the multiple drive technology, no previous work was reported on the methodology to realize a cost-effective design of multi-drive belt conveyors. This study investigates a design approach for multiple drive belt conveyors with the objective to achieve the lowest life cycle cost of multi-drive belt conveyors for a specified material transport task. For this purpose, an optimization model for the cost-effective design of multi-drive conveyor systems is formulated on the basis of the recommendations of the DIN 22101 and SANS 1313 standards. For a given number of intermediate drive stations, the proposed model optimizes a set of design parameters so that the minimum equivalent annual cost of a conveyor can be attained whilst handling the transport requirements and design conditions. The conveyor parameters optimized in this study are the rated powers of motors, the rated torques of gear reducers, the diameters and wrap angles of drive pulleys, the belt width, the belt speed, the lengths of the belt sections not nestled between drive pulleys, the spacings between idler rolls and the shell diameters and shaft diameters of idler rolls. For benchmark analysis purposes, a similar optimization model is also developed for the single drive technology. Described as mixed integer nonlinear programming (MINLP) problems, the two optimization models are solved using the MIDACO solver embedded in the MATLAB environment. The results of this study show the validity and effectiveness of the design model proposed for multi-drive belt conveyors. The results also indicate that the multiple drive technology is more beneficial for the conveying over long distances. The impact of the possible instability of inflation throughout the project lifetime is also investigated through three hypothetical scenarios, which involve a fixed inflation rate, a higher fluctuating inflation rate and a lower fluctuating inflation rate, respectively. The results of this sensitivity analysis show that the most cost-effective multi-drive belt conveyors obtained under a fixed inflation rate is robust enough against limited fluctuations of this parameter.
Dissertation (MEng)--University of Pretoria, 2017.
Electrical, Electronic and Computer Engineering
MEng
Unrestricted
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4

DI, NAPOLI MARIA. "Modeling and experimental characterization of belt drive systems in micro-hybrid vehicles." Doctoral thesis, Politecnico di Torino, 2018. http://hdl.handle.net/11583/2715955.

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Анотація:
Belt Drive Systems (BDS) constitute the traditional automotive mechanism used to power the main internal accessories (such as the alternator, water pump and air conditioning pump) taking power from the engine's crankshaft rotational motion. BDS usually work in the severe ambient conditions of the engine compartment and are subject to highly dynamic excitations coming from the crankshaft harmonics. The substitution of the traditional alternator with an electric machine, namely Belt Starter Generator (BSG), is the most promising micro-hybrid technology towards a quick and effective satisfaction of the current regulations of fuel consumption and pollutant emissions reduction. The use of a BSG leads to increased stresses in the already complex front end accessory drive. As a matter of fact, a BSG is an electrical machine able to work both as motor and as generator and defines two distinct functioning modes of the drive, namely motor and alternator modes. The relative alternation of tight and slack spans profoundly changes the functionality of the overall drive and affects its transmissions capability and efficiency, furthermore resulting in NVH (noise vibration harshness) effects that need to be carefully addressed. Traditional automatic tensioners acting on the slack span of the alternator mode application are not capable of facing the irregular stresses of a BSG-based BDS which requires the use of a tensioning device capable of keeping the belt tension inside a safe range and of preventing slippage during all the operating conditions of the drive. With this goal many solutions are currently being investigated, such as the cooperation of two tensioners one for each span, active tensioners, double arm tensioners or hydraulic tensioners. The critical issues due to the involvement of BSG in BDS require a deep study focused on the tension conditions of the belt and its influence on the overall efficiency of the system. The aim of the research described in this thesis is to obtain a defined modelling approach of belt drive systems for micro-hybrid vehicles and to validate it through extensive experimental analysis. To obtain a reliable testing environment, a dedicated full-electric test rig was designed and realized. The test rig presented in this work is capable of assuring the repeatability and accuracy of the measurements leaving aside the uncertainties deriving from the irregularities of the ICE behaviour that usually affect the experimental activities conducted on front engine accessory drives. After providing both the modelling and testing environment as assets for the analysis, several experimental activities are carried out with the goal of assessing the dynamic behaviour of belt drive systems and their efficiency, comparing the performances of different tensioning solutions, understanding the behaviour in static and dynamic conditions of a traditional automatic tensioner and one example of an omega twin arm tensioner, which is the tensioning solution most explored by the manufacturers at present. The ultimate goal of gaining a complete understanding of belt drive systems in the special case of micro-hybrid vehicles is eventually fulfilled by an experimental validation of the static and dynamic models proposed.
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5

Zhu, Farong. "Nonlinear dynamics of one-way clutches and dry friction tensioners in belt-pulley systems." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1158689667.

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6

Kilic, Ergin. "Structured Neural Networks For Modeling And Identification Of Nonlinear Mechanical Systems." Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614735/index.pdf.

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Анотація:
Most engineering systems are highly nonlinear in nature and thus one could not develop efficient mathematical models for these systems. Artificial neural networks, which are used in estimation, filtering, identification and control in technical literature, are considered as universal modeling and functional approximation tools. Unfortunately, developing a well trained monolithic type neural network (with many free parameters/weights) is known to be a daunting task since the process of loading a specific pattern (functional relationship) onto a generic neural network is proven to be a NP-complete problem. It implies that if training is conducted on a deterministic computer, the time required for training process grows exponentially with increasing size of the free parameter space (and the training data in correlation). As an alternative modeling technique for nonlinear dynamic systems
this thesis proposed a general methodology for structured neural network topologies and their corresponding applications are realized. The main idea behind this (rather classic) divide-and-conquer approach is to employ a priori information on the process to divide the problem into its fundamental components. Hence, a number of smaller neural networks could be designed to tackle with these elementary mapping problems. Then, all these networks are combined to yield a tailored structured neural network for the purpose of modeling the dynamic system under study accurately. Finally, implementations of the devised networks are taken into consideration and the efficiency of the proposed methodology is tested on four different types of mechanical systems.
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7

Lioy, Gerald T. "Optimization of an elastic drive belt system using an algorithm of automated optimal design /." Online version of thesis, 1985. http://hdl.handle.net/1850/9042.

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8

Pakhotin, Ivan. "Fusion of first principles driven and system science approaches to advance radiation belt forecasting." Thesis, University of Sheffield, 2014. http://etheses.whiterose.ac.uk/7260/.

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Modern radiation belt models can be broadly split into either physics-driven diffusion based algorithms, or data science techniques that utilise the continuous data coverage from satellites at geostationary orbit and the Lagrange point L1 to apply statistical data analysis methods to predict electron fluxes at geostationary orbit. The first kind, while posessing generality due to their physical nature, lack accuracy compared to their data-driven counterparts. This is because the magnetosphere is a highly complex system that is not easy to model and its dynamics are not yet fully understood. Meanwhile, data-driven methods possess statistical accuracy, but cannot predict outside their operating parameters, and so on their own provide no information about what happens in the wider radiation belt region. This thesis is devoted to the development of a model that combines the two approaches into one unified system, attempting to combine the predictive range of physical modelling with the accuracy of the data-driven approach. This model uses geosynchronous orbit fluxes predicted using an advanced data science technique as an input to drive a physics-based radiation belt modelling code. The model has been developed and tested for a range of energy channels, magnetospheric conditions, and with various modifications. It was validated using data from NASA's recent Van Allen probes mission and with NOAA's GOES-13 geostationary satellite. The model results are in good agreement with observations, with the sources of inaccuracies explored in the manuscript. This work is a first attempt to create such a model, and potential improvements are outlined that should further increase accuracy. A further modification of the model is explored that is found to provide superior performance at geostationary orbit at the cost of degraded performance elsewhere. It is proposed to use this modification in tandem with the main model, where accurate information about geostationary orbit is required. The modification has been tested on long-duration time periods and was found to generate good predictions for high-energy electron fluxes. The role of electromagnetic ion cyclotron (EMIC) waves is explored using wave vector analysis and calculation of minimum resonant energies. The aim is to identify what effect EMIC waves have on electron dynamics at energies below 1 MeV. The conclusions are that EMIC waves, under certain conditions, do affect these electron populations in the magnetosphere, and their effect should be included in a representative radiation belt model. This is suggested as a further improvement to the simulation.
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9

Weekes, Alix M. "Systems for the automotive industry for improved safety of pregnant occupants." Thesis, Loughborough University, 2010. https://dspace.lboro.ac.uk/2134/6374.

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Анотація:
The thesis presents an investigation of pregnant women s safety and comfort needs during car travel. A survey is used to investigate all aspects and problems of car travel. This survey is a comprehensive examination of the entire driving activity with much detail of reported difficulties from pregnant women that forms a novel resource for the automotive engineers. The survey results are used to generate guidelines for the automotive industry. A series of sled tests are presented that investigate seat belt use in pregnancy including the use of lap belt positioners. The peak abdominal pressure results clearly agree with current guidelines that the lap belt should be positioned across the hips and not across the abdomen. This research includes a novel anthropometric dataset for 107 pregnant women including measurements especially selected for the field of automotive design and to describe the changes of pregnancy. This includes investigation of pregnant driver s proximity to the steering wheel. A novel measurement of knee splay is used to define the pregnant women s preference to sit with their knees widely spaced instead of knees together, in both normal sitting and in a car. Comparison is made between the pregnant women's measurements and the available data in the literature for non-pregnant women and males, and this shows that pregnant women can be excluded from designs if the accommodation does not consider their needs. The pregnant women's anthropometric data is presented as a novel website in order to make the data available to the automotive industry. This website is generated for use by automotive engineers and is designed to suit their usability needs and the general trends within the industry, in order to make the site more user-friendly and more likely to be used as a reference for pregnant occupant's needs.
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10

Silva, Carlos Alexandre Ferreira Da. "Modeling and optimization of power losses in poly-V belt transmissions : Application to the Front Engine Accessory Drive of trucks." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSEI079/document.

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Ces travaux s’inscrivent dans le cadre du projet EDIT(Efficient Distribution Truck, FUI19), piloté par le groupe Volvo Trucks, dont l’objectif de réduction de consommation pour 2020 est fixé à 13% par rapport à un véhicule actuel EURO-6. Le projet EDIT porte sur cinq axes techniques d’amélioration dont un consiste en l’obtention d’un système optimisé de transmission par courroie poly-V au regard des pertes de puissance. Actuellement les faces avant de moteur sont perfectionnées sur le plan mécanique ; cela signifie que la durée de vie de ses composants est optimisée, et que les nuisances vibratoires sont réduites. Par contre, des améliorations peuvent être apportées sur le plan énergétique. Cette thèse, qui a pour objectif d’investiguer les possibilités de réduction et d’optimisation des pertes de puissance sur les façades accessoires, se décline en trois parties : une caractérisation par l’analyse mécanique dynamique des matériaux viscoélastiques des courroies poly-V et des composantes de façade ; une modélisation, une optimisation et une implémentation logicielle des modèles de pertes de puissance ; validées par une dernière partie expérimentale sur banc d’essais. Les pertes de puissances dans une face avant moteur sont de plusieurs types : des pertes internes à la courroie poly-V (hystérésis du caoutchouc), des pertes externes à la courroie (glissement poulie/courroie) et des pertes internes aux composants (frottement dans les roulements). Ces pertes peuvent désormais être quantifiées et optimisées grâce aux modèles développés durant cette thèse. Ces modèles ont été validés et implémentés dans un outil de simulation (PLFead, Power Loss Front engine accessory drive), qui a été développé pour optimiser les pertes de puissance en tenant compte des paramètres de design et de fonctionnement des faces avant moteur
This work is a part of the Efficient Distribution Truck (EDIT, FUI 19) project, led by Volvo Trucks, whose objective is to reduce distribution vehicles’ fuel consumption for 2020 by 13% when compared with the current production vehicle EURO-6. The EDIT project targets five areas of research and technical solutions, one of which consists of obtaining an optimized poly-V belt transmission concerning the power losses. In terms of lifetime of the mechanical components, reduction of noise and vibrations, the Front Engine Accessory Drives (FEADs) are currently one of the most technologically sophisticated systems. However, further improvements can be made to make the vehicles more energy efficient. This thesis, which aims at investigating possibilities for reducing and optimizing the power losses in the FEADs, is composed of three main parts: the characterization of the viscoelastic materials of the poly-V belts via Dynamic Mechanical Analysis (DMA) and the FEAD components; the modeling, the optimization and the implementation of the power loss models in a simulation tool; and their experimental validation through a test bench. The power losses occurring in a FEAD are of several types: poly-V internal losses (hysteresis of the belt-rubber), poly-V external losses (belt/pulley slip) and losses from the accessory drives (friction inside the bearings). These power losses can be quantified and optimized thanks to the models developed throughout this thesis. These models have been validated and implemented in a simulation tool (PLFead, Power Loss Front engine accessory drive), which has been developed to optimize the power losses taking into consideration the design parameters and operating conditions of the FEAD
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Книги з теми "Belt Drive Systems"

1

Dufva, Kari. Development of finite elements for large deformation analysis of multibody systems. Lappeenranta: Lappeenranta University of Technology, 2006.

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2

R, Stapper William, and Lewis Research Center, eds. Evaluation of navy 9 cst oil in Bell helicopter M412 HP gearboxes. [Cleveland, Ohio]: National Aeronautics and Space Administration, Lewis Research Center, 1998.

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3

Honma, K. T. Hardware interface between controlling computer and Bell & Howell 3700B tape drive used in FM playback system. [Denver, Colo.?]: U.S. Dept. of the Interior, Geological Survey, 1988.

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Geological Survey (U.S.), ed. Hardware interface between controlling computer and Bell & Howell 3700B tape drive used in FM playback system. [Denver, Colo.?]: U.S. Dept. of the Interior, Geological Survey, 1988.

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5

Institute, Highway Loss Data, ed. Driver injury experience in 1990 models equipped with air bags or automatic belts. Arlington, VA (1005 N. Glebe Rd. Suite 800, Arlington 22201): Highway Loss Data Institute, 1991.

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6

Ovtov, Vladimir. Machine parts. Course design. ru: INFRA-M Academic Publishing LLC., 2021. http://dx.doi.org/10.12737/1171976.

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The textbook discusses the methodology of course design of general-purpose drives with a single-stage gearbox (cylindrical, conical and worm) and a V-belt or chain transmission. The procedure for calculating gears and constructing assembly drawings of gearboxes is shown, the development of specifications using the COMPASS-3D computer-aided design system is described. Examples of the design of drawings of the general type of the drive, assembly drawings of gearboxes and working drawings of parts of various types of gearboxes are given. Meets the requirements of the federal state educational standards of higher education of the latest generation. It is intended for independent work of students of engineering specialties studying in the bachelor's degree and specialty.
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7

1956-, Thomas David, and Pragmatic Programmers (Firm), eds. Pragmatic unit testing: In C# with NUnit. Raleigh, N.C: Pragmatic Bookshelf, 2004.

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Hunt, Andy. Pragmatic unit testing: In C♯ with NUnit. 2nd ed. Raleigh, N.C: Pragmatic Bookshelf, 2007.

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9

Zhang, Lixin. Dynamic analysis of viscoelastic serpentine belt drive systems. 1999.

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Nouri, Mostafa. Design optimization and active control of serpentine belt drive systems with two-pulley tensioners. 2005.

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Частини книг з теми "Belt Drive Systems"

1

Martinez-Guerra, Rafael, and Juan Luis Mata-Machuca. "Fault detection in a belt-drive system." In Understanding Complex Systems, 67–74. Cham: Springer International Publishing, 2013. http://dx.doi.org/10.1007/978-3-319-03047-0_5.

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2

Kerimova, I. M. "On Possibility of Using a Toothed Belt Drive in a Drive to Rocker-Machines." In Advances in Intelligent Systems and Computing, 763–67. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-35249-3_99.

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3

Pi, Vu Ngoc, Nguyen Khac Tuan, Le Xuan Hung, Nguyen Thi Hong Cam, and Tran Thi Phuong Thao. "Determining Optimum Partial Transmission Ratios of Mechanical Driven Systems Using a V-Belt Drive and a Three-Stage Helical Reducer." In Advances in Material Sciences and Engineering, 81–88. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-8297-0_11.

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4

Vetyukov, Yury, and Vladimir Eliseev. "The Model of a Deformable String with Discontinuities at Spatial Description in the Dynamics of a Belt Drive." In Mechanics and Model-Based Control of Advanced Engineering Systems, 275–83. Vienna: Springer Vienna, 2013. http://dx.doi.org/10.1007/978-3-7091-1571-8_30.

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Cam, Nguyen Thi Hong, Vu Ngoc Pi, Nguyen Khac Tuan, Le Xuan Hung, and Tran Thi Phuong Thao. "Determining Optimal Partial Transmission Ratios of Mechanical Driven Systems Using a V-Belt Drive and a Helical Reducer with Second-Step Double Gear-Sets." In Advances in Engineering Research and Application, 261–69. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-030-04792-4_35.

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Musselman, M., and D. Djurdjanovic. "Improvement of Belt Tension Monitoring in a Belt-Drive Automated Material Handling System." In Advances in Sustainable Manufacturing, 135–40. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-20183-7_20.

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7

Kanus, Malte, Alexander Hoffmann, Ludger Overmeyer, and Bernd Ponick. "Linear Direct Drive for Light Conveyor Belts to Reduce Tensile Forces." In Cyber-Physical Systems and Control, 398–406. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-34983-7_38.

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8

Mejia, Leonardo, Fabricio Frantz, Daniel Ponce, and Daniel Martins. "Best Operation Regions in a Planar Cable Driven System." In Advances in Robot Kinematics 2022, 93–100. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-08140-8_11.

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9

Denisova-Schmidt, Elena, and Peter Firnhaber. "Smooth Operator: The Chair as the Drive Belt of the German Governance System." In Leading a Board, 211–36. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-16-0727-1_9.

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Denisova-Schmidt, Elena, and Peter Firnhaber. "Smooth Operator: The Chair as the Drive Belt of the German Governance System." In Leading a Board, 139–60. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-3197-8_7.

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Тези доповідей конференцій з теми "Belt Drive Systems"

1

Balta, Berna, Bülent Balta, Abdülkadir Cengiz, Fazıl Önder Sönmez, and Armağan Arıcı. "Torque Loss Measurements on Poly V-Ribbed Belt Drive Systems." In ASME 2012 11th Biennial Conference on Engineering Systems Design and Analysis. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/esda2012-82245.

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Efficient belts can provide the same magnitude of energy savings as energy-efficient motors. Therefore, belt drives deserve greater attention, so that their losses should be minimized. The belt drive power losses are a combination of torque losses and speed losses. However, the determination of belt drive behavior in terms of power losses requires extensive experimental investigations. Therefore, in this study, belt slip and torque losses were investigated experimentally with a laboratory constructed test bench. Measurement System Analysis (MSA) was performed in order to investigate the test rig reliability. Special attention was paid for experimental test setup, testing and modeling of torque loss behavior of V-ribbed belt drive systems. Significant design parameters were investigated.
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2

Beikmann, R. S., Noel C. Perkins, and A. G. Ulsoy. "Nonlinear Coupled Response of Serpentine Belt Drive Systems." In ASME 1993 Design Technical Conferences. American Society of Mechanical Engineers, 1993. http://dx.doi.org/10.1115/detc1993-0036.

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Abstract This theoretical and experimental study identifies a key nonlinear mechanism that promotes strongly coupled dynamics of serpentine belt drive systems. Attention is focused on a prototype three-pulley system that contains the essential features of automotive serpentine drives having automatic (spring-loaded) tensioners. A theoretical model is presented that describes pulley and tensioner arm rotations, and longitudinal and transverse belt response. A recent investigation demonstrates that infinitesimal belt stretching creates a linear mechanism that couples transverse belt response to tensioner arm rotation. Here, it is further demonstrated that finite belt stretching creates a nonlinear mechanism that may lead to strongly coupled response in the presence of an internal resonance. Theoretical and experimental results confirm the existence of this nonlinear coupling mechanism. In particular, it is shown that very large transverse belt vibrations can result from small resonant torque pulses applied to the crankshaft or accessory pulleys.
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3

Hwang, S. J., N. C. Perkins, A. G. Ulsoy, and R. J. Meckstroth. "Rotational Response and Slip Prediction of Serpentine Belt Drive Systems." In ASME 1993 Design Technical Conferences. American Society of Mechanical Engineers, 1993. http://dx.doi.org/10.1115/detc1993-0249.

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Abstract A nonlinear model is developed which describes the rotational response of automotive serpentine belt drive systems. Serpentine drives utilize a single (long) belt to drive all engine accessories from the crankshaft. An equilibrium analysis leads to a closed-form procedure for determining steady-state tensions in each, belt span. The equations of motion are linearized about the equilibrium state and rotational mode vibration characteristics are determined from the eigenvalue problem governing free response. Numerical solutions of the nonlinear equations of motion indicate that, under certain engine operating conditions, the dynamic tension fluctuations may be sufficient to cause the belt to slip on particular accessory pulleys. Experimental measurements of dynamic response are in good agreement with theoretical results and confirm theoretical predictions of system vibration, tension fluctuations, and slip.
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4

Vijayakumar, N., A. Seeliger, and G. Eltaliawi. "Co-simulation of complex belt conveyor drive systems." In 5th IET International Conference on Power Electronics, Machines and Drives (PEMD 2010). Institution of Engineering and Technology, 2010. http://dx.doi.org/10.1049/cp.2010.0134.

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5

Saikrishna, S., G. Liang, K. Chandrashekhara, L. R. Oliver, and S. G. Holmes. "Predictive Fatigue Model for Serpentine Belt Drive Systems." In SAE 2006 World Congress & Exhibition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2006. http://dx.doi.org/10.4271/2006-01-0018.

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6

Leamy, Michael J., and Tamer M. Wasfy. "Dynamic Finite Element Modeling of Belt-Drives." In ASME 2001 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/detc2001/vib-21342.

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Abstract In this study, a dynamic finite element model is developed for pulley belt-drive systems. The belt is modeled using truss elements, while the pulleys are modeled using rotating circular constraints, for which the driver pulley’s angular velocity is prescribed. Frictional contact between the pulleys and the belt is modeled using a penalty formulation with frictional contact governed by a Coulomb-like tri-linear friction law. The dynamic response of the drive is then studied by incorporating the model into an explicit finite element code, which can maintain time-accuracy for arbitrarily large rotations and for long simulation times. The finite element solution is validated through comparison to an exact analytical solution of a steadily-rotating, two-pulley drive. Several response quantities are compared, including the normal and tangential (friction) force distributions between the pulleys and the belt, the driven pulley angular velocity, and the belt span tensions. Excellent agreement is found.
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Rodriguez, Jesus, Rifat Keribar, and Jielong Wang. "A Comprehensive and Efficient Model of Belt-Drive Systems." In SAE 2010 World Congress & Exhibition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2010. http://dx.doi.org/10.4271/2010-01-1058.

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8

Oh, Kyoyul, Matthew Plauman, Jerry Romanick, Ian Farmer, Michael Aimone, and David Barnaby. "Performance Comparison Between Chain and Belt Cam-Drive Systems." In SAE 2001 World Congress. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2001. http://dx.doi.org/10.4271/2001-01-0365.

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Leamy, Michael J., and Tamer M. Wasfy. "Dynamic Finite Element Modeling of Belt-Drives Including One-Way Clutches." In ASME 2001 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/imece2001/de-23254.

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Abstract In this study, a dynamic finite element model is developed for pulley belt-drive systems, including systems incorporating oneway clutches. The belt is modeled using truss elements, while the pulleys are modeled using rotating circular constraints, for which the driver pulley’s angular velocity is prescribed. Frictional contact between the pulleys and the belt is modeled using a penalty formulation with frictional contact governed by a Coulomb-like tri-linear friction law. One-way clutch elements are modeled using a proportional torque law supporting torque transmission in a single direction. The dynamic response of the drive is then studied by incorporating the model into an explicit finite element code, which can maintain time-accuracy for large rotations and for long simulation times. The finite element solution is validated through comparison to an exact analytical solution of a steadily-rotating, two-pulley drive. Several response quantities are compared, including the normal and tangential (friction) force distributions between the pulleys and the belt, the driven pulley angular velocity, and the belt span tensions. Excellent agreement is found. Results for a second belt-drive example involving a one-way clutch demonstrates the utility and flexibility of the finite element solution approach.
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Ptakh, G. K., N. F. Evsin, D. A. Zvezdunov, D. V. Rozhkov, and A. E. Yakovenko. "Switched reluctance motor for electric drive of overland belt conveyor." In 2014 17th International Conference on Electrical Machines and Systems (ICEMS). IEEE, 2014. http://dx.doi.org/10.1109/icems.2014.7013794.

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Звіти організацій з теми "Belt Drive Systems"

1

Okura, Kiyoshi, and Yoshihiko Tatsumi. Analysis of Squeal Noise Radiated From Serpentine Belt for Accessories Drive Systems. Warrendale, PA: SAE International, September 2005. http://dx.doi.org/10.4271/2005-08-0644.

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2

Okuda, Kazuma, Yasuyuki Komatsu, Shigeru Aoki, Tadashi Fujiwara, and Youichi Nakahara. Study on ISG Belt Drive System for Idling Stop System. Warrendale, PA: SAE International, May 2005. http://dx.doi.org/10.4271/2005-08-0400.

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3

Valencia, Oscar, Juan José Díaz, and Diego A. Parra. Assessing Macro-Fiscal Risk for Latin American and Caribbean Countries. Inter-American Development Bank, November 2022. http://dx.doi.org/10.18235/0004530.

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This paper provides a comprehensive early warning system (EWS) that balances the classical signaling approach with the best-realized machine learning (ML) model for predicting fiscal stress episodes. Using accumulated local effects (ALE), we compute a set of thresholds for the most informative variables that drive the correlation between predictors. In addition, to evaluate the main country risks, we propose a leading fiscal risk indicator, highlighting macro, fiscal and institutional attributes. Estimates from different models suggest significant heterogeneity among the most critical variables in determining fiscal risk across countries. While macro variables have higher relevance for advanced countries, fiscal variables were more significant for Latin American and Caribbean (LAC) and emerging economies. These results are consistent under different liquidity-solvency metrics and have deepened since the global financial crisis.
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4

Seginer, Ido, James Jones, Per-Olof Gutman, and Eduardo Vallejos. Optimal Environmental Control for Indeterminate Greenhouse Crops. United States Department of Agriculture, August 1997. http://dx.doi.org/10.32747/1997.7613034.bard.

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Increased world competition, as well as increased concern for the environment, drive all manufacturing systems, including greenhouses, towards high-precision operation. Optimal control is an important tool to achieve this goal, since it finds the best compromise between conflicting demands, such as higher profits and environmental concerns. The report, which is a collection of papers, each with its own abstract, outlines an approach for optimal, model-based control of the greenhouse environment. A reliable crop model is essential for this approach and a significant portion of the effort went in this direction, resulting in a radically new version of the tomato model TOMGRO, which can be used as a prototype model for other greenhouse crops. Truly optimal control of a very complex system requires prohibitively large computer resources. Two routes to model simplification have, therefore, been tried: Model reduction (to fewer state variables) and simplified decision making. Crop model reduction from nearly 70 state variables to about 5, was accomplished by either selecting a subset of the original variables or by forming combinations of them. Model dynamics were then fitted either with mechanistic relationships or with neural networks. To simplify the decision making process, the number of costate variables (control policy parametrs) was recuced to one or two. The dry-matter state variable was transformed in such a way that its costate became essentially constant throughout the season. A quasi-steady-state control algorithm was implemented in an experimental greenhouse. A constant value for the dry-matter costate was able to control simultaneously ventilation and CO2 enrichment by continuously producing weather-dependent optimal setpoints and then maintaining them closely.
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5

Schelzig, Karin, and Kirsty Newman. Promoting Inclusive Education in Mongolia. Asian Development Bank, November 2020. http://dx.doi.org/10.22617/wps200305-2.

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Children with disabilities suffer disproportionately from the learning crisis. Although they represent only about 1.5% to 5% of the child population, they comprise more than half of out-of-school children globally. Inspired by a commitment that every child has the right to quality education, a growing global drive for inclusive education promotes an education system where children with disabilities receive an appropriate and high-quality education that is delivered alongside their peers. The global commitment to inclusive education is captured in the Sustainable Development Goal 4—ensuring inclusive and equitable education and promoting lifelong learning opportunities for all. This paper explores inclusive education for children with disabilities in Mongolia’s mainstream education system, based on a 2019 survey of more than 5,000 households; interviews with teachers, school administrators, education ministry officials, and social workers; and visits to schools and kindergartens in four provinces and one district of the capital city. Mongolia has developed a strong legal and policy framework for inclusive education aligned with international best practice, but implementation and capacity are lagging. This is illustrated using four indicators of inclusive education: inclusive culture, inclusive policies, inclusive practices, and inclusive physical environments. The conclusion presents a matrix of recommendations for government and education sector development partners.
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6

Devereux, Stephen. Policy Pollination: A Brief History of Social Protection’s Brief History in Africa. Institute of Development Studies (IDS), December 2020. http://dx.doi.org/10.19088/ids.2020.004.

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The relatively recent emergence and sustained rise of social protection as a policy agenda in Africa can be understood as either a nationally owned or ‘donor-driven’ process. While elements of both can be seen in different countries at different times, this paper focuses on the pivotal role of transnational actors, specifically international development agencies, as ‘policy pollinators’ for social protection. These agencies deployed a range of tactics to induce African governments to implement cash transfer programmes and establish social protection systems, including: (1) building the empirical evidence base that cash transfers have positive impacts, for advocacy purposes; (2) financing social protection programmes until governments take over this responsibility; (3) strengthening state capacity to deliver social protection, through technical assistance and training workshops; (4) commissioning and co-authoring national social protection policies; (5) encouraging the domestication of international social protection law into national legislation. Despite these pressures and inducements, some governments have resisted or implemented social protection only partially and reluctantly, either because they are not convinced or because their political interests are not best served by allocating scarce resources to cash transfer programmes. This raises questions about the extent to which the agendas of development agencies are aligned or in conflict with national priorities, and whether social protection programmes and systems would flourish or wither if international support was withdrawn.
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7

Selvaraju, Ragul, Hari Shankar, and Hariharan Sankarasubramanian. Metamodel Generation for Frontal Crash Scenario of a Passenger Car. SAE International, September 2020. http://dx.doi.org/10.4271/2020-28-0504.

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A frontal impact scenario was simulated using a Finite Element Model of a Hybrid III 50th percentile male (LSTC, Livermore CA) along with seatbelt, steering system and driver airbags. The boundary conditions included acceleration pulse to the seat and the outputs including injury measures in terms of Head Injury Criterion (HIC), Normalized Neck Injury Criterion (NIJ) and Chest Severity Index (CSI) were extracted from the simulations. The kinematics of the Hybrid III were validated against the kinematics of post mortem human surrogates (PMHS) available in the literature. Using the validated setup, metamodels were generated by creating a design of varying different parameters and recording the responses for each design. First, the X and Z translation of dummy along the seat is provided as input for which there was no variation in the head injury criterion (HIC). Next, the input pulse to the seat is parameterized along with the seatbelt loading and the results are obtained respectively. The outputs, in terms of injury measures, are generated in the form of metamodels as a function of the parameters. The occupant model used for the frontal crash scenario in LS-Dyna is validated against the previously available crash experimental data. A total of 100 design points was generated with a varying combination of parameters. An increase in various injury measures was observed with an increase in the scale factor of the acceleration pulse. Also, it was found that chest severity index increased with an increase in the scale factor of the seat belt loading force.
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8

Selvaraju, Ragul, Hari Shankar, and Hariharan Sankarasubramanian. Metamodel Generation for Frontal Crash Scenario of a Passenger Car. SAE International, September 2020. http://dx.doi.org/10.4271/2020-28-0504.

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Анотація:
A frontal impact scenario was simulated using a Finite Element Model of a Hybrid III 50th percentile male (LSTC, Livermore CA) along with seatbelt, steering system and driver airbags. The boundary conditions included acceleration pulse to the seat and the outputs including injury measures in terms of Head Injury Criterion (HIC), Normalized Neck Injury Criterion (NIJ) and Chest Severity Index (CSI) were extracted from the simulations. The kinematics of the Hybrid III were validated against the kinematics of post mortem human surrogates (PMHS) available in the literature. Using the validated setup, metamodels were generated by creating a design of varying different parameters and recording the responses for each design. First, the X and Z translation of dummy along the seat is provided as input for which there was no variation in the head injury criterion (HIC). Next, the input pulse to the seat is parameterized along with the seatbelt loading and the results are obtained respectively. The outputs, in terms of injury measures, are generated in the form of metamodels as a function of the parameters. The occupant model used for the frontal crash scenario in LS-Dyna is validated against the previously available crash experimental data. A total of 100 design points was generated with a varying combination of parameters. An increase in various injury measures was observed with an increase in the scale factor of the acceleration pulse. Also, it was found that chest severity index increased with an increase in the scale factor of the seat belt loading force.
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9

Delmer, Deborah P., Douglas Johnson, and Alex Levine. The Role of Small Signal Transducing Gtpases in the Regulation of Cell Wall Deposition Patterns in Plants. United States Department of Agriculture, August 1995. http://dx.doi.org/10.32747/1995.7570571.bard.

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The combined research of the groups of Delmer, Levine and Johnson has led to a number of interesting findings with respect to the function of the small GTPase Rac in plants and also opened up new leads for future research. The results have shown: 1) The Rac13 protein undergoes geranylgeranlyation and is also translocated to the plasma membrane as found for Rac in mammals; 2) When cotton Rac13 is highly- expressed in yeast, it leads to an aberrant phenotype reminiscent of mutants impaired in actin function, supporting a role for Rac13 in cytoskeletal organization; 3) From our searches, there is no strong evidence that plants contain homologs of the related CDC42 genes found in yeast and mammals; 4) We have identified a rather unique Rac gene in Arabidopsis that has unusual extensions at both the N- and C-terminal portions of the protein; 5) New evidence was obtained that an oxidative burst characterized by substantial and sustained production of H202 occurs coincident with the onset of secondary wall synthesis in cotton fibers. Further work indicates that the H202 produced may be a signal for the onset of this phase of development and also strongly suggests that Rac plays an important role in signaling for event. Since the secondary walls of plants that contain high levels of lignin and cellulose are the major source of biomass on earth, understanding what signals control this process may well in the future have important implications for manipulating the timing and extent of secondary wall deposition. 6) When the cotton Rac13 promoter is fused to the reporter gene GUS, expression patterns in Arabidopsis indicate very strong and specific expression in developing trichomes and in developing xyelm. Since both of these cell types are engaged in secondary wall synthesis, this further supports a role for Rac in signaling for onset of this process. Since cotton fibers are anatomically defined as trichomes, these data may also be quite useful for future studies in which the trichomes of Arabidopsis may serve as a model for cotton fiber development; the Rac promoter can therefore be useful to drive expression of other genes proposed to affect fiber development and study the effects on the process; 7) The Rac promoter has also been shown to be the best so far tested for use in development of a system for transient transformation of developing cotton fibers, a technique that should have many applications in the field of cotton biotechnology; 8) One candidate protein that may interact with Rac13 to be characterized further in the future is a protein kinase that may be analogous to the PAK kinase that is known to interact with Rac in mammals.
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10

Replace V-Belts with Notched or Synchronous Belt Drives, Motor Systems Tip Sheet #5 (Fact Sheet). Office of Scientific and Technical Information (OSTI), November 2012. http://dx.doi.org/10.2172/1056711.

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