Relevant bibliographies by topics / Main gear

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Main gear'

Author: Grafiati
Published: 28 June 2021
Last updated: 28 May 2022

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Journal articles on the topic "Main gear"

1

Ding, Yuan, Xia Li, Yong Ji Yang, Shi Qiang Ma, and Yue Xue Pan. "Ascertainment of Machine Tool Adjustment and Processing Parameters for Spiral Bevel Gears in a Heavy Vehicle Main Driving System." Advanced Materials Research 616-618 (December 2012): 2030–33. http://dx.doi.org/10.4028/www.scientific.net/amr.616-618.2030.

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Based on partial conjugation principle, revised machine tool adjustment parameters and processing parameters which can make big gear and small gear be in points conjugation meshing progress are obtained after the cutting tooth plan and rough gear parameters of spiral bevel gears in a heavy vehicle main driving system were determined. Ideal gear contact spots are gained by gear contact area rolling experiment, which show that calculation theory and methods above-described are practicable and effective for improving meshing quality of spiral bevel gears in heavy vehicle main driving system.
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Janulevičius, Algirdas, and Kazimieras Giedra. "ANALYSIS OF MAIN DYNAMIC PARAMETERS OF SPLIT POWER TRANSMISSION." TRANSPORT 23, no. 2 (June 30, 2008): 112–18. http://dx.doi.org/10.3846/1648-4142.2008.23.112-118.

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The review carried out had shown one basic approach of split power transmission to the organization of drive which is applied to stepless transmissions of tractors and parallel hybrid cars. In the split power transmission the power split device uses a planetary gear. Tractor engine power in the split power transmission is transmitted to the drive shaft via a mechanical and hydraulic path. The theoretical analysis of main parameters of the split power transmission of the tractor is presented. The angular velocity of sun and coronary gears of the differential set is estimated by solution of the system of equations in which one equation is made for planetary differential gear, and another ‐ for hydrostatic drive. The analysis of the transmission gear‐ratio dependencies on the ratio of hydraulic machines capacities is carried out. Dependence of the variation of angular velocity of the coronary and the sun gears on the ground speed of the tractor is presented. Dependence of sum shaft torque and its constituents, carried by mechanical and hydraulic lines, on sum shaft angular velocity and ground speed of tractor and engine speed is also presented.
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Song, Ai Ping, Wen Jie Gao, and Shang Gao. "Research on Trapping Oil Property and Operating Characteristic of Arch Gear Pump." Advanced Materials Research 230-232 (May 2011): 107–12. http://dx.doi.org/10.4028/www.scientific.net/amr.230-232.107.

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The arch gear pump is a new kind of gear pump. Based on the mesh characteristics of arch gears, the relations between the operating characteristic and the main parameters of arch gear are analyzed. The conclusion is drawn: the arch gear pump’s non-pocketed oil phenomena can be achieved with opting for the main parameters of arch gear; the pump can work smoothly and get high efficiency.
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Sun, Ying Shi, Tian Min Guan, and Xu Zhang. "Dynamic Simulation of Cycloid Wheel at Two Support Points of Needle Gear pin for New Three-Gear Pin-Cycloid Driven Speed Reducer." Advanced Materials Research 291-294 (July 2011): 1195–99. http://dx.doi.org/10.4028/www.scientific.net/amr.291-294.1195.

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Pin-cycloid driven speed reducer with three cycloid gears adopts the new driving structure of three cycloid gears at eccentric angle of 120 between each other. Three main stresses act on the cycloid gears: the stress between pin gear and cycloid wheel gear, the stress on cycloid wheel by cylinder pin of output mechanism and the stress on cycloid wheel by bearing of rotating arm. In this paper, the stress between needle gear and cycloid wheel gear is analyzed mainly by analysis.
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Alipiiev, Ognyan. "Bidirectional modification of gears in the generalized theory of meshing." MATEC Web of Conferences 287 (2019): 01006. http://dx.doi.org/10.1051/matecconf/201928701006.

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An important part of “Generalized theory”, developed by the author of this article, is the “bidirectional modification” of involute gears. The main point of the proposed modification is that together with the traditional “radial modification” of the basic rack, an additional “tangential modification” of the side profiles of the rack-cutters is introduced. As a result, the area of possible existence of involute gear drives in the generalized theory is considerably extended. Based on the bidirectional modification, a new classification of involute gears at their meshing with a rack cutter is proposed. The classification is characterized by a significant variety, which is composed of thirteen different types of gears: a zero gear; two radially modified gears; two tangentially modified gears and eight two-way modified gears. Based on the bidirectional modification in radial and tangential directions, a new classification of the involute gear drives is proposed. The classification is composed of sixteen different types of gear drives: a zero gear drive, three equally-modified gear drives; two balanced gear drives; five positive gear drives and five negative gear drives.
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Cui, Huan Yong, Xi Jie Tian, and Dong Liang Wang. "Design Technique Research of Fine-Forged Spur Bevel Gear Tooth Profile Modification." Key Engineering Materials 443 (June 2010): 170–76. http://dx.doi.org/10.4028/www.scientific.net/kem.443.170.

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Gear tooth profile modification can be featured to improve working stability of gear equipments, abate noise and vibration, enhance loading ability and prolong usage life of the gears. Fine forged spur bevel gear are formed with molds, so it is economical to modify the gears by means of modifying mold cavity. Whether the modified gears can be separated from the mold with easiness is proposed to be the basic criterion of gear tooth profile modification design. Near the big ends and tooth roots is mainly the area which affects demolding after modification. According to the modified gear configuration, mathematical model is built to calculate the demolding check at any modification points on the fine forged spur bevel gear profile. And a corresponding program is developed, which is the main tool for the gear tooth profile modification design, and practical calculation has carried out.
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Surnis, Prathmesh. "Design and Analysis of 2-Stage Gearbox for ATV Applications." International Journal for Research in Applied Science and Engineering Technology 9, no. 9 (September 30, 2021): 2193–210. http://dx.doi.org/10.22214/ijraset.2021.38326.

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Abstract: The main objective of this project is to design and develop a 2-Stage- Reduction gearbox for all terrain vehicles application. Gearbox is a mechanical unit consisting of series of gears within a housing (casing) or a simple gear train. It is the main component of the powertrain system as it provides speed and torque conversions from the Engine or CVT to the wheels. The gears inside of gearbox can be any one of a number of different types of the gear that are available in the market i.e., from spur gears to worm gears and planetary gears as well. In this report the gearbox is made from a helical gear train. This report focuses on selection of overall reduction ratio of the gearbox, material selection, selection of gear dimensions, selection of shaft dimension, design of key and bearing selection from SKF bearing catalogue. The bending and wear strengths are calculated to determine factor of safety and later, Finite element analysis is performed to validate the results. Keywords: Geartrain, Shaft Design, SKF Bearings, Solidworks, FEA
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Wu, Yi-Chang, and Tze-Cheng Wu. "EMBODIMENT DESIGN OF NOVEL 5-SPEED REAR DRIVE HUBS FOR BICYCLES." Transactions of the Canadian Society for Mechanical Engineering 39, no. 3 (September 2015): 431–41. http://dx.doi.org/10.1139/tcsme-2015-0032.

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This paper presents embodiment design of 5-speed rear drive hubs for bicycles. A 7-link, 2-degrees of freedom (DOF) compound planetary gear train as the main body of a rear drive hub is introduced. The relationship between the number of coaxial links of a planetary gear train and the number of gear stages that a drive hub can provide with is discussed. By means of kinematic analysis, four speed ratios of the planetary gear train are derived, which represents four forward gears of the rear drive hub. By adding a direct-drive gear, five forward gears can be provided and two feasible clutching sequence tables are synthesized. Manual translational-type gear-shifting mechanisms are further designed to incorporate with the planetary gear train for appropriately controlling the gear stage. The power-flow path at each gear stage is checked to verify the feasibility of the proposed design. Finally, two novel 5-speed bicycle rear drive hubs are presented.
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Koval'chuk, Oleksandr, Volodymyr Nezhebovs'kyj, Alexander Permyakov, Alexander Klochko, and Serhii Riabchenko. "PROCESSING OF HARDENED CYLINDRICAL GEAR WHEELS OF THE CUTTING GEARBOX OF THE COMBINE UKD 200-500." Cutting & Tools in Technological System, no. 95 (December 26, 2021): 57–70. http://dx.doi.org/10.20998/2078-7405.2021.95.07.

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The article discusses the latest developments of unique technological methods of gear milling of cylindrical gears for preliminary blade gear processing of hardened cylindrical gears of the cutting reducer of the UKD200-500 coal mining harvester for the final gear grinding of gear teeth with modulus m = 16 mm, with hardness HRC 56 ... 62. The peculiarity of the design of special hob cutters is that a circle passing through the lower boundary points of the involute is used as the palloid of the machine gearing of the tool and part. Pre-cutting the teeth of hardened wheels with carbide milling cutters allows you to remove the main allowance for the final gear grinding.
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Xuejun, Li, Jiang Lingli, Hua Dengrong, Yin Daoxuan, and Yang Dalian. "An Analysis of the Gear Meshing Characteristics of the Main Planetary Gear Trains of Helicopters Undergoing Shafting Position Changes." International Journal of Aerospace Engineering 2021 (July 30, 2021): 1–12. http://dx.doi.org/10.1155/2021/9965818.

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The complex three-shaft three-reducer structural designs of helicopter transmission systems are prone to changes in the relative positions of shafting under the conditions of main rotor and tail rotor loads. These changes will affect the transmission characteristics of the entire transmission system. In this study, the planetary gear trains of helicopters were examined. Due to the fact that these structures are considered to be the most representative structures of the main reducers of helicopters, they were selected as the study objects for the purpose of examining the meshing characteristics of planetary gear trains when the relative positions of the shafting changed due to the position changes of the main rotor shafts under variable load conditions. It was found that by embedding the comprehensive time-varying meshing stiffness values of the main rotor shafts at different positions, a dynamic model of the relative position changes of the planetary gear trains could be established. Then, combined with the multibody dynamics software, the meshing characteristics of the sun gears, and the planetary gears, the planetary gears and the inner ring gears were simulated and analyzed under different inclinations and offsets of the shafting. The results obtained in this study revealed the following: (1) the average meshing force of the gears increased with the increases in the angle inclinations, and the meshing force between the sun gears and the planetary gears increased faster than the meshing force between the planetary gears and the inner ring gears. It was observed that during the changes in the shafting tilt positions, obvious side frequency signals had appeared around the peak of the meshing frequency in the spectrum. Then, with the continuous increases in the tilt position, the peak was gradually submerged; (2) the average meshing force of the gears increased with the increases in the offset, and the increasing trend of the meshing force between the sun gears and the planetary gears was similar to that observed between the planetary gears and the inner ring gears. It was found that when the shafting offset position changed, there were obvious first and second frequency doubling in the spectrum; (3) the mass center orbit radii of the sun gears increased with the increases in the shafting position changes, and the changes in the angular tilt position were found to have greater influencing effects on the mass center orbit radii of the sun gears than the changes in the offset positions. This study’s research findings will provide a theoretical basis for future operational status monitoring of the main transmission systems of helicopters and are of major significance for improvements in the operational stability of helicopter transmission systems, which will potentially ensure safe and efficient operations.
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Dissertations / Theses on the topic "Main gear"

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Fattah, Ryu. "The noise generation by a main landing gear door." Thesis, University of Southampton, 2016. https://eprints.soton.ac.uk/390837/.

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Experimental measurements and numerical simulations were conducted on a simplified main landing gear model that consists of a leg-door, and a main strut in a parallel configuration. The effects of varying the leg-door angle of attack, and the gap distance between the two elements, were initially studied by two-dimensional and low-order numerical simulations, using the unsteady Reynolds-Averaged Navier-Stokes equations. The strut diameter was specified to the same diameter as a full-scale main landing gear, and simulated under a free-stream Mach number of 0.2, and a Reynolds number based on the cylinder diameter of 1:7 x 106. Further three-dimensional and high-order numerical simulations were conducted on models with a constant gap distance of 8.7% of the cylinder diameter. The high-order solver evaluates the three-dimensional Navier-Stokes equations in the full-conservation form, with the Zonal Detached-Eddy Simulation model. The fidelity of the numerical solver was improved in two parts. Firstly, an Eigenvalue analysis for a multiple-block environment was developed to optimise the combination of spatial and filtering schemes for maximum grid resolution that is numerically stable. Secondly, a grid quality metric, which correlates strongly to the solution accuracy, was developed. A validation database of experimental measurements on a tripped 26% scale interaction model, at a free-stream Mach number of 0.09, and a Reynolds number based on the cylinder diameter of 2 x 105, was developed at the 2:1 m x 1:5 m wind tunnel at the University of Southampton. The experimental and numerical results show that the wake generated by the interaction model is dominated by low frequencies that correspond to the vortex shedding modes of the cylinder, and the door. As the door angle is increased from 0 to 10.7 degrees, the intensity of the cylinder shedding mode decreased. The sound pressure levels of the radiated noise were calculated using the FW-H method. The dominant noise source is a compact dipole, which reduced in strength as the door angle was increased.
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Čavojský, Tomáš. "Návrh podvozku malého dvoumístného letounu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-442821.

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This diploma thesis deals with the landing gear design of the small two-seat aircraft. The introduction focuses on the conceptual gear design and shock absorber computational dynamic characteristic model. The practical part is focused on the landing gear construction according to the selected parameters based on the conceptual and computational model. The diploma thesis ends with strength calculations and production documentation.
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Howcroft, Christopher. "A bifurcation and numerical continuation study of aircraft main landing gear shimmy." Thesis, University of Bristol, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.617699.

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This thesis presents a bifurcation and numerical continuation study into the occurrence of shimmy instability in an aircraft main landing gear (MLG) of single side-stay, dualwheel design. The dynamics are expressed in terms of three rotational degrees of freedom (Dofs) aligned with the side-stay plane, and a fourth translational DoF representing compression of the main strut. These DoFs are modelled by oscillators that are coupled directly through the geometric configuration of the system, as well as through the tyre/ground interface. Using this representation of the MLG system we focus in this thesis on the nonlinear effects of geometric orientation and mechanical freeplay employing bifurcation analysis techniques to highlight their effects on the MLG stability. First, a changing side-stay orientation angle is investigated. Shimmy is studied by means of a two-parameter bifurcation analysis in terms of the landing gear forward velocity and loading force. For this a three-DoF model is used that does not include axial compression. This formulation along with suitable parameters allows for comparison with the existing literature, and an agreement is demonstrated with previous results for a zero side-stay angle. Subsequent variation of this angle is explored and a consistent picture presented, capturing the (transition of the two-parameter bifurcation diagram us a function of this angle. This shows a considerable increase in the complexity of the dynamics for intermediate side-stay angles. The appearance of an additional shimmy mode is observed and a region of tri-stability found where three distinct shimmy types coexist. For the study of freeplay the MLG model is extended to include axial compression; this axial DoF is required to accurately represent freeplay, introduced to the torque links of the system. Parameter values are chosen here to represent a typical mid-range civil aircraft MLG. The addition of freeplay is shown to result in shimmy oscillations that occur within the MLC operating envelope; their properties depend on both the size and 'shape' of freeplay. Freeplay and geometric coupling arc also considered together via consideration of a non-zero side-stay angle. Here, additional dynamic complexity is introduced in the presence of freeplay and, again , this coincidence with the appearance of a new shimmy mode. Further complex phenomena also appear, including multiple- frequency and chaotic-type oscillations, as well as complex transients. The non-zero geometry produce asymmetry and this results in a great sensitivity of the small-amplitude MLG behaviour to the exact shape of freeplay. Therefore, geometric orientation and freeplay a.re found to have significant effects and, when combined, they work together to produce additional complex phenomena, not otherwise observed when considered in isolation.
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GOTIA, BOGDAN, and MUCINO JORGE LOYA. "Advanced hybrid manufacturing process for high precision ring of a planetary gear – main focus on Abrasive Waterjet Machining." Thesis, KTH, Industriell produktion, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-193043.

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Under år 2008 uppskattades den totala produktionen av kugghjul inom bilindustrin till 2000 – 2500 miljoner detaljer, varav 1000 - 1400 miljoner av dessa är av hög kvalité [1]. För precisionskugghjul med modul under 1 mm kan tidsbegränsning och kostnader kopplade till design av skärverktyget elimineras genom att tillämpa en flexibel tillverkningsmetod som tillexempel abrasiv vattenskärning (AWJM). Denna studie undersöker designen av ett hybridtillverkningssystem konfigurerat kring AWJM samt föreslår finbearbetningsprocess via konventionella bearbetningsmetoder. Den tekniska möjligheten att producera kuggring av hög precision testas med en 5-axlig vattenjetmaskin och utvärderas enligt kvalitets nivåer för DIN-standard. För detta ändamål studerades ett kugghjul med modul 0,55 mm, 199 tänder, 110 mm i ytterdiameter och 72 mm i innerdiameter samt en tjocklek på 6 mm gjord av Armox T500, höghållfast stål. Resultaten visar på hög potential att uppnå ISO standardkvalité för kugghjul. Vissa kvalitetsegenskaper, definierade i DIN- och ISO-standarder, till exempel ytfinhet med låga värden; Ra 0,8 μm, uppnås vid användning av AWJM. Andra kvalitetskännetecken som profilavvikelse är relaterade till parametrar som skäreffekt, matningshastighet, mängd abrasivmedel, etc. Framtagna värden sträcker sig från Q10 och Q11 enligt DIN3967 vilket möjliggör slutoperationer som till exempel slipning. Geometrisk avvikelse, på ovansidan, gav en maximalt värde på 7 μm med en standardavvikelse på 4 μm. Jetstrålens eftersläpning observerades och kan kompenseras för medan resultatet av rundade hörn existerar i alla skärning med AWJ. Radiell förskjutning, tandtjocklek och index avvikelser visar värden som kan förbättras tillsammans med processoptimering, maskinkalibrering och eliminering av inneboende positionsavvikelser i maskinen. Varje enskild geometri kräver specifika processparametrar och CAM-programmens algoritmer behöver vidare optimeras för arbeten med tämligen små geometrier.
Production of gears for the automotive industry during 2008 is estimated to have been between 2000 – 2500 million pieces, from which 1000 to 1400 million pieces were high quality gears [1]. For precision gears with module below 1 mm, the time limitations and costs associated with the design of the cutting tool can be eliminated by using a flexible manufacturing technology such as Abrasive WaterJet Machining (AWJM). This project investigates the design of a hybrid manufacturing system configured by use of AWJM and proposed finishing processes using conventional machining methods. The technical feasibility is analysed to produce high precision ring gears using a 5-axes AWJM system to achieve DIN standards quality levels. For this purpose, a gear with a module of 0.55 mm, 199 teeth and 110 mm in the outer diameter and 130 teeth and 72 mm in the inner diameter with a thickness of 6 mm is studied; the selected material is Armox T500, a high strength steel. The results indicate high potential of producing ISO quality standard gears. Certain quality characteristics defined in DIN and ISO standards, for instance surface roughness – values as low as Ra 0.8 μm, are possible to achieve accurately by using AWJM. Others quality features as profile deviation, are related to parameters as cutting power, feed rate, abrasive feed rate, etc. The displayed values ranged Q10 and Q11 according to DIN3967 which allows for use of further finishing operations such as grinding. The top geometry deviations of a 0.3 mm cut, display a maximum value of 7 μm with an average value of 4 μm. Observed jet lag effects can be improved. Rounded corner effect exists in all AWJ cuts. Runout, tooth thickness and index deviations show values that can be improved together with process optimization, machine calibration and elimination of machine inherent positioning deviations. Each particular geometry needs specific process parameters and CAM software algorithms need further optimization for working with rather small design geometries.
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Bellocchio, Andrew Thomas. "Drive System Design Methodology for a Single Main Rotor Helicopter." Thesis, Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/7524.

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The transformation of Joint forces to be lighter, more lethal, and capable of deploying from multiple dispersed locations free of prepared landing zones requires a dedicated heavy lift VTOL aircraft capable of rapidly delivering large payloads, such as the 20 to 26 ton Future Combat System, at extended ranges in demanding terrain and environmental conditions. Current estimates for a single main rotor configuration place the design weight over 130,000 pounds with an installed power of approximately 30,000 horsepower. Helicopter drive systems capable of delivering torque of this magnitude succeeded in the Russian Mi-26 helicopters split-torque design and the Boeing VERTOL Heavy Lift Helicopter (HLH) prototypes traditional multi-stage planetary design. The square-cube law and historical trends show that the transmission stage weight varies approximately as the two-thirds power of torque; hence, as the size and weight of the vehicle grows, the transmissions weight becomes an ever-increasing portion of total gross weight. At this scale, optimal gearbox configuration and component design holds great potential to save significant weight and reduce the required installed power. The drive system design methodology creates a set of integrated tools to estimate system weight and rapidly model the preliminary design of drives system components. Tools are provided for gearbox weight estimation and efficiency, gearing, shafting, and cooling. Within the same architecture, the designer may add similar tools to model subcomponents such as support bearings, gearbox housing, freewheeling units, and rotor brakes. Measuring the relationships between key design variables and system performance metrics reveals insight into the performance and behavior of a heavy lift drive system. A parametric study of select design variables is accomplished through an intelligent Design of Experiments that utilizes Response Surface Methodology to build a multivariate regression weight model. The model permits visualization of the design space and assists in optimization of the drive system preliminary design. This methodology is applied to both the Boeing HLH and the Russian Mi-26 main gearboxes. This study applies the drive system design methodology to compare the Mi-26 split-torque gearbox over the Boeing HLH multi-stage planetary gearbox in a single main rotor heavy lift helicopter.
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Ringshia, Aditya K. "Aerodynamic Measurements in a Wind Tunnel on Scale Models of a 777 Main Landing Gear." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/34583.

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Aerodynamic measurements were taken over models of the Boeing 777 high fidelity isolated landing gear in the 6- by 6-foot Virginia Tech Stability Wind Tunnel (VT-SWT) at a free-stream Mach number of 0.16. Noise control devices (NCD) were developed at Virginia Tech [9] to reduce noise by shielding gear components, reducing wake interactions and by streamlining the flow around certain landing gear components. Aerodynamic measurements were performed to understand the flow over the landing gear and also changes in the flow between "Baseline" and "NCD" configurations (without and with Noise Control Devices respectively). Hot-film, Pitot-static measurements and flow visualization using tufts were performed over an isolated 26% scale-model high fidelity landing gear for the "Baseline" and "NCD" configurations. Contours of turbulence intensity, normalized wake velocity and normalized total pressure loss for both configurations are compared. The "Baseline" configuration was also compared with the NASA Ames study conducted by Horne et al [7]. Hot-film measurements are also compared to Microphone Phased Array results which were acquired at Virginia Tech by Ravetta [8]. A novel technique for processing hot-film measurements by breaking turbulence into octave bands as acoustic measurements is presented. Particle Image Velocimetry (PIV) measurements were taken at six different locations over the 13% scale-model landing gear with no door and at a truck angle of zero degrees. Results are compared to PIV measurements taken over the wheels of a four-wheel landing gear by Lazos [10-12]. PIV results such as average velocity contours and vectors, streamlines and instantaneous velocity contours and vectors are presented. Results presented from PIV and flow visualization are in good agreement with results from Lazos [10-12].
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Trojánek, Tomáš. "Návrh podvozku malého dvoumístného letounu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-377755.

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The aim of this master thesis is modification of landing gear for accomplishment CS-23 regula-tion from that purpose, because landing gear in the use can't pass this type of certification. The first part examines the alternatives of landing gear with consideration optimal technical and eco-nomical difficulty. After finding optimal type of landing gear with shock absorber is there part of designing and computing the load. Last part of thesis is about stress analysis of whole con-cept and reconsidering final changes.
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Van, Mierlo Koen. "Computational analysis of the flow field and noise radiation of a generic main landing gear configuration." Thesis, University of Southampton, 2014. https://eprints.soton.ac.uk/388076/.

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This study investigates the flow field and acoustics of a generic four wheel main landing gear. The landing gear is an important airframe noise source during the approach phase. The characteristics of the flow field around the bogie area of the main landing gear are largely unknown. CFD simulations using the DES turbulence model have been used to calculate the unsteady flow field around a generic landing gear model. The surface pressure data has been sampled and used in a FW-H solver to determine far field noise levels. Two different landing gear models have been used, a simplified geometry and a more realistic complex geometry. Three different bogie angles have been simulated: horizontal bogie aligned with the flow, 10⁰ toe up and 10⁰ toe down. Strong streamwise vortices are generated at the front wheels of the landing gear. The trajectory of these vortices determines where the turbulent flow interacts with the downstream components. This interaction leads to surface pressure fluctuations which are a major noise source. The flow field of the simplified configurations shows a consistent trend of the trajectory of the streamwise vortices with respect to changes in bogie angle. The far field noise levels generated by the different components of the simplified configurations are related to the distance at which the streamwise vortices pass. The additional components of the complex landing gear geometry change the characteristics of the flow field. The strong streamwise vortices persist but they do not show the same trend as for the simplified configurations. The wake of the articulation link generates a turbulent in flow for the other components. The different characteristics of the flow field of the complex configurations lead to significant changes in the far field noise levels of the components compared to the simplified configurations.
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Novák, Josef. "Návrh podvozku VUT200 TwinCobra." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-232017.

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The goal of following master thesis is to design variety of configuration and retraction options of VUT200 TwinCobra landing gear. For each option are a wheel base and a gauge set up by possibility of main landing gear retraction. Next, CS 23 demands and stress analysis are followed. There is a view of twin engine aircraft landing gear disclosed as well.
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Kubiena, Jaromír. "Návrh úpravy letadla WT10 Advantic s pevným podvozkem dle předpisu CS-23." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-318135.

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In this thesis, we deal with the design of a shock absorber variant for the type of main landing gear design of the aircraft WT10 Advantic. Then we focus on the design of the selected variant of the main landing gear. Next, we follow regulation CS-23 demands to calculate the load cases for the selected main lending gear. Then we design shock absorber based on the load during landing. We compile the equation of motion of the aircraft, which describes motion of the aircraft during landing, then we compute the equation. Finally, we focus on a stress analysis of the main landing gear and the shock absorber.
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Books on the topic "Main gear"

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Daugherty, Robert H. Cornering characteristics of the main-gear tire of the space shuttle orbiter. [Washington, D.C.]: National Aeronautics and Space Administration, 1988.

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Davis, Pamela A. Quasi-static and dynamic response characteristics of F-4 bias-ply and radial-belted main gear tires. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1997.

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Davis, Pamela A. Quasi-static and dynamic response characteristics of F-4 bias-ply and radial-belted main gear tires. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1997.

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Davis, Pamela A. Quasi-static and dynamic response characteristics of F-4 bias-ply and radial-belted main gear tires. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1997.

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Davis, Pamela A. Quasi-static and dynamic response characteristics of F-4 bias-ply and radial-belted main gear tires. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1997.

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Davis, Pamela A. Quasi-static and dynamic response characteristics of F-4 bias-ply and radial-belted main gear tires. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1997.

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McFadden, P. D. Analysis of the vibration of the input level pinion in RAN Wessex helicopter main rotor gearbox WAK143 prior to failure. Melbourne: Aeronautical Research Laboratories, 1985.

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Tom, Badgett, ed. Official Sega Genesis and Game Gear strategies, 2ND Edition. Toronto: Bantam Books, 1991.

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Sandler, Corey. Official Sega Genesis and Game Gear strategies, 3RD Edition. New York: Bantam Books, 1992.

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Schütz, Friedrich. Das Mainzer Rad an der Gera, Kurmainz und Erfurt 742-1802: Eine Ausstellung der Stadt Mainz zum Erfurter Stadtjubiläum 742-1992. Mainz am Rhein: P. von Zabern, 1991.

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Book chapters on the topic "Main gear"

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Blech, Niklas, Holger Cermak, André Sitzmann, Adrian Sorg, Daniel Fuchs, Thomas Tobie, and Karsten Stahl. "Load Carrying Capacities, Strength Numbers, and Main Influence Parameters for Different Gear Materials and Heat Treatment Processes." In Dudley's Handbook of Practical Gear Design and Manufacture, 639–83. 4th ed. Boca Raton: CRC Press, 2021. http://dx.doi.org/10.1201/9781003126881-11.

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Sivaranjani, T., D. V. T. G. Pavan Kumar, C. M. Manjunatha, and M. Manjuprasad. "Fatigue Life Estimation of Typical Fighter Aircraft Main Landing Gear Using Finite Element Analysis." In Advances in Structural Integrity, 39–52. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-7197-3_4.

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Antal, T. A., and A. Antal. "Cylindrical Worm Gears with Improved Main Parameters." In New Trends in Mechanism Science, 625–32. Dordrecht: Springer Netherlands, 2010. http://dx.doi.org/10.1007/978-90-481-9689-0_71.

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Mazac, M. "Stand for Measuring Temperatures of the Main Gears of Automobile Differential." In Lecture Notes in Mechanical Engineering, 139–44. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-05203-8_20.

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"Main Quality Control Activities." In Gear Motor Handbook, 583–602. Berlin, Heidelberg: Springer Berlin Heidelberg, 1995. http://dx.doi.org/10.1007/978-3-642-79589-3_31.

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"Cracking in an Aircraft Main Landing Gear Sliding Strut." In Handbook of Case Histories in Failure Analysis, 7–10. ASM International, 1993. http://dx.doi.org/10.31399/asm.fach.v02.c9001291.

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Kumar, Ashwani, Yatika Gori, and Pravin P. Patil. "Finite Element Analysis-Based Thermo-Mechanical Performance Study of Heavy Vehicle Medium Duty Transmission Gearbox." In Handbook of Research on Advancements in Manufacturing, Materials, and Mechanical Engineering, 322–36. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-4939-1.ch015.

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The main objective of this chapter is to investigate the performance of automobile transmission gearbox under the influence of load, rotational speed, and lubrication on multi speed gearbox gear surface. Gear oil SAE 80W-90 was used as gearbox lubricant, for cooling of transmission gearbox for high performance. An assumption has been made at the air-gear oil mist within transmission is under steady state condition, in isothermal equilibrium with the transmission gear oil bath of lubricant. The lubrication in multi speed transmission is subjected to thermo-elastohydrodynamic lubrication. The present chapter deals with the thermo-mechanical performance study of multi speed transmission (4 speed, excluding reverse gear) system, which combines transient structure analysis of the gear train assembly. The engaged gear teeth pairs transmit torque subjected to thermo-elastohydrodynamic arrangements of lubrication. The study here analyzed transmission in second gear pair.
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Dudás, Illés. "Main operating charac teristics and quality assessment of worm gear drives." In The Theory and Practice of Worm Gear Drives, 260–88. Elsevier, 2004. http://dx.doi.org/10.1016/b978-190399661-4/50011-3.

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"Failure of a Main Landing Gear on a Light Airplane." In ASM Failure Analysis Case Histories: Air and Spacecraft. ASM International, 2019. http://dx.doi.org/10.31399/asm.fach.aero.c9001018.

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Kumar, Ashwani. "Low to High Speed Transient Structural and Thermal Temperature Measurement of Oil-Lubricated Multi-Speed Heavy Vehicle Transmission Gearbox System Based on FEA." In Advanced Numerical Simulations in Mechanical Engineering, 1–21. IGI Global, 2018. http://dx.doi.org/10.4018/978-1-5225-3722-9.ch001.

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The main objective of this chapter is dynamic structural and thermal analysis of multi speed transmission gearbox (medium duty truck) using Finite Element Analysis (FEA). To evaluate the dynamic strength of transmission gearbox assembly transient structural analysis was performed. Dynamic varying loads at different rotational speed were applied to perform the transient analysis. In gear meshing operation at high rotational speed and loading condition, frictional heat is generated inside gearbox assembly. To reduce the effect of frictional heat, gear oil is used. In this research study gear oil SAE 85W140 was used for cooling and performance enhancement. Steady state thermal analysis was performed to evaluate the thermal effect of frictional heat, rotational speed of shafts (pinion, gear) and load with gear oil lubrication. In thermal effect gearbox surface temperature was measured at different points. FEA simulation results have been validated using experimental results available in literature.
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Conference papers on the topic "Main gear"

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Kennedy, John, Eleonora Neri, and Gareth J. Bennett. "The Reduction of Main Landing Gear Noise." In 22nd AIAA/CEAS Aeroacoustics Conference. Reston, Virginia: American Institute of Aeronautics and Astronautics, 2016. http://dx.doi.org/10.2514/6.2016-2900.

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Ringshia, Aditya, Patricio Ravetta, Wing Ng, and Ricardo Burdisso. "Aerodynamic Measurements of the 777 Main Landing Gear Model." In 12th AIAA/CEAS Aeroacoustics Conference (27th AIAA Aeroacoustics Conference). Reston, Virigina: American Institute of Aeronautics and Astronautics, 2006. http://dx.doi.org/10.2514/6.2006-2625.

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Finkbeiner, Josua, Patrick Dunlap, Bruce Steinetz, Jeffrey DeMange, and Daniel Newswander. "Investigations of Shuttle Main Landing Gear Door Environmental Seals." In 41st AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2005. http://dx.doi.org/10.2514/6.2005-4155.

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Howcroft, C., B. Krauskopf, M. Lowenberg, S. Neild, and B. Krauskopf. "Effects of Freeplay on Aircraft Main Landing Gear Stability." In AIAA Atmospheric Flight Mechanics Conference. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2012. http://dx.doi.org/10.2514/6.2012-4730.

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Ito, Yasushi, Yuzuru Yokokawa, Takehisa Takaishi, Kazuomi Yamamoto, Tohru Hirai, Yosuke Ueno, Kazuhide Isotani, et al. "Noise Reduction of Regional Jet Two-Wheel Main Landing Gear." In 25th AIAA/CEAS Aeroacoustics Conference. Reston, Virginia: American Institute of Aeronautics and Astronautics, 2019. http://dx.doi.org/10.2514/6.2019-2481.

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Cao, Liang, Yubin Xia, Yong Shen, Jinglin Wang, Tianmin Shan, and Zeli Lin. "Fault Characteristics Analysis of Planetary Gear of Helicopter Main Reducer." In 2019 Prognostics and System Health Management Conference (PHM-Qingdao). IEEE, 2019. http://dx.doi.org/10.1109/phm-qingdao46334.2019.8942930.

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Lentini, Antonino Sergio, Sebastian Flock, and Yann Vonderscher. "Gear Whine Analysis of an Integrated-Spring Split Gear System." In ASME 2017 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/detc2017-68245.

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The need to reduce weight in internal combustion (IC) engines introduces new or increased NVH challenges. In particular, gear-related noise such as rattle and whine need to be addressed. This paper discusses a methodology aimed at simulating a novel “split gear” system designed to counteract the rattle noise typically generated in accessory drive gears on combustion engines. In particular, the focus is on the increased gear whine associated with this system. The ‘split gear’ system is simulated as a multi-body system incorporating contact force prediction developed by Siemens. It enables efficient identification of the contact between gear teeth based on their intrinsic involute geometry, including the effects from microgeometry corrections as well as relative displacements and misalignments of the gears. The gear contact force is evaluated taking into account both compliances for the global bulk and local contact. The multi-body approach and dedicated modeling technique permitted the investigation of interaction between gears of the ‘split gear’ system and appropriate replication of the operational boundary conditions. The activity presented in this paper consisted of two main phases, measurements of the dynamic behavior of the split gear system and multi-body simulations. The former allows gathering reference data for validation of the simulation model built in the latter phase. The results show the potential of the new method to analyze gear systems in view of NVH performance.
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Ding, Huafeng, Shuai Liu, Peng Huang, Changwang Cai, and Zhen Huang. "Automatic Structural Synthesis of Epicyclic Gear Trains With One Main Shaft." In ASME 2015 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/detc2015-47101.

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Design of automatic gear boxes with better performance is a pursuit goal of the modern automobile industry. In order to develop CAD method for the creative design of automatic gear boxes, this paper proposes an automatic method for the structure synthesis of one degree of freedom (DOF) epicyclic gear trains (EGTs) with one main shaft which serve as the key mechanisms in automatic gear boxes. First, based on the graph representation of EGTs, the canonical perimeter graphs and the corresponding canonical adjacency matrices are obtained. Then, based on the canonical adjacency matrices, the characteristic number strings are obtained and used to identify isomorphism in the synthesis process. Third, an automatic method is proposed to generate the basic graphs of the topological graphs of EGTs, and the basic graphs up to 9 links are synthesized. After that, based on the structural characteristics for the graphs of EGTs, an automatic method is proposed to synthesize the topological graphs of EGTs from the basic graphs, and an algorithm for the detection of rigid subchains in EGTs is also presented. Finally, a program is developed, and 1-DOF EGTs having one main shaft with up to 9 links are synthesized.
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Daugherty, Robert H., and Sandy M. Stubbs. "Spin-Up Studies of the Space Shuttle Orbiter Main Gear Tire." In Aerospace Technology Conference and Exposition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 1988. http://dx.doi.org/10.4271/881360.

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Khorrami, Mehdi R., William M. Humphreys, and David P. Lockard. "An Assessment of Flap and Main Landing Gear Noise Abatement Concepts." In 21st AIAA/CEAS Aeroacoustics Conference. Reston, Virginia: American Institute of Aeronautics and Astronautics, 2015. http://dx.doi.org/10.2514/6.2015-2987.

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Reports on the topic "Main gear"

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Bozzuto, Matthew P., and Susan J. Evans. Development of the C-17 - Main Landing Gear Post Container, CNU-677/E. Fort Belvoir, VA: Defense Technical Information Center, April 2007. http://dx.doi.org/10.21236/ada470982.

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Picard, Mary. F/A-18A/B/C/D Main Landing Gear Control Unit Hydraulic 2A Supply Line Pressure Spikes and Emergency Port Restrictor Ground and Flight Tests Evaluation. Fort Belvoir, VA: Defense Technical Information Center, November 2002. http://dx.doi.org/10.21236/ada409130.

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Hellström, Lisa, and Linda Beckman. "Det är lite mer så här mainstream att ha psykisk ohälsa" : Samtal om ungas behov och livsfärdigheter. Malmö universitet, 2021. http://dx.doi.org/10.24834/isbn.9789178771691.

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Denna rapport ingår i forskningsprojektet Att skapa goda livsfärdigheter bland unga. Den första delrapporten var en nationell och internationell kartläggning över initiativ och insatser för att främja psykisk hälsa bland unga. Bland insatser som verkar mer lovande – och till synes har goda möjligheter att göra skillnad för ungas psykiska hälsa - framträder insatser vars syfte är att höja kunskapen om psykisk hälsa bland unga och vuxna. Ökad kunskap om psykisk hälsa har visat sig vara ett viktigt verktyg för att utveckla färdigheter i hur man tolkar och förstår sina egna känslor och sin kropp och när man behöver kontakta vården. Dessutom är dessa insat-ser ofta samhällsekonomiskt kostnadseffektiva, eftersom de ger unga bättre livsfärdigheter och på sikt leder till minskat vårdsökande och bättre förutsättningar att klara skolan och i förlängningen arbetslivet. Sådana satsningar går även i linje med Barnkonventionen 24§ om alla barns rätt till bästa möjliga hälsa, som sedan 2020 är lag i Sverige. Rekommendat-ioner från den första delrapporten innefattar att rusta unga med färdigheter för att möta livets svårigheter och höja kunskapen om psykisk ohälsa. Det handlar också om att bistå vuxna med kunskap om psykisk hälsa och verk-tyg som främjar hälsa för att kunna stödja unga. Insatser för att främja unga personers hälsa bör följas upp under en längre tid.I denna rapport presenteras röster från unga och yrkesverksamma vuxna i ungas närhet om ungas livssituation kopplat till livsfärdigheter, psykisk hälsa och behov av stöd. Genom att lyssna in unga kan vi bättre hitta framgångsfaktorer för att främja ungas psykiska hälsa och välbefinnande.
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Kløcker Larsen, Rasmus, and Maria Boström. “Renen får aldrig betesro”: Konsekvenser av Bolidens gruva och vägen i Stihkeområdet för Voernese sameby. Stockholm Environment Institute, June 2021. http://dx.doi.org/10.51414/sei2021.008.

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Denna rapport presenterar en studie av Voernese samebys erfarenheter av de konsekvenser som gruvan i Stihkeområdet fört med sig, en gruva som drevs av Boliden Mineral AB mellan år 1976–1988. Det finns i dag ett stort kunskapsglapp angående vilka de faktiska konsekvenserna är av gruvindustri på renskötsel och annan samisk markanvändning. Detta är så vitt vi vet första gången som forskningen empiriskt belyser konsekvenserna av gruvindustrin och försöken till efterbehandling av gruvområdet utifrån en samebys egna erfarenheter och kunskap. Studien genomfördes 2019–2020 i ett samarbete mellan samebyn, Svenska Samernas Riksförbund och SEI. Datainsamlingen har bestått av arbetsmöten, intervjuer, workshops, dokumentanalys och kartering med stöd av RenGIS och forskning om störningszoner. Fokus i denna rapport är på just Voernese samebys erfarenheter, gruvans konsekvenser för andra samebyar eller icke-renskötande samer i området har därför inte inkluderats. Resultaten visar den omfattande påverkan som gruvan haft på samebyn, dels under driftperioden men i högsta grad också efteråt. Eftersom samebyn bedriver samrenskötsel i Stihkeområdet med Vilhelmina Södra sameby, på vars mark gruvverksamheten bedrevs, har samebyn påverkats både av direkta markförluster och betesskador från gruvområdet liksom andra störningarna under drifttiden. I nutid handlar de största konsekvenserna om påverkan från vägen som drogs i tidigare väglöst land och störningarna på renen från besöksnäringen. Detta har försvårat för renen att finna betesro, inneburit omfattande merarbete och ökade kostnader för samebyn vid samling och flytt, samt medfört stress och oro för samebyns medlemmar liksom även förlust av traditionell kunskap. Renskötseln försvåras även av kvarlämnade borrör och järnskrot från SGU:s provborrningar. Studien visar också hur samebyn exkluderades från beslutsfattandet när Bolidens gruva etablerades på 1970-talet och nu återigen har marginaliserats i samband med tillståndsprövningen för Vilhelmina Minerals planer för återupptagning av brytningen. Dessa forskningsresultat är viktiga för att korrigera en vanlig missuppfattning i den politiska och offentliga debatten kring gruvindustrin: att gruvindustri och renskötsel skulle kunna samexistera utan någon större påverkan på renskötseln. De bidrar också till en ökad förståelse för den omfattande påverkan som ett gruvprojekt, samt dess följdeffekter, kan ha på en grannsameby trots det att själva gruvområdet ligger utanför samebygränsen. I ett vidare perspektiv bidrar studien med ytterligare ett empiriskt baserat exempel på hur gruvbolag och stat marginaliserar samisk kunskap och missbrukar samebyars deltagande i miljöbedömningar. Dessa problem härrör främst från det faktum att svensk lagstiftning inte ger tillräckligt skydd för samiska rättigheter. Det hänger även ihop med statens tvetydiga roll i hanteringen av de intressekonflikter som uppstår när man både har en skyldighet att skydda samiska rättigheter och ska tillgodose olika samhälls- och företagsekonomiska intressen i utvinningen av mineraler. Denna brist på ansvarstagande, som samebyn upplever från statens sida, visar med all tydlighet att den koloniala exploateringen av naturresurserna i Sápmi inte är ett historiskt fenomen utan något som i högsta grad fortgår än i dag. Som ett exempel har inga ansträngningar gjorts för att se över om den begränsade ekonomiska ersättningen som staten genomförde under 1960–70 talet verkligen motsvarar de faktiska skador som samebyn fått uthärda. På kortare sikt skulle många förbättringar troligen kunna åstadkommas genom enskilda insatser för att adressera de problem som samebyn har i Stihkeområdet. Exempelvis skulle kommun och länsstyrelse kunna ingripa för att hantera de problem som besöksnäringen och friluftslivet orsakar och regeringen skulle kunna ge SGU i uppdrag att återställa tidigare prospekteringsverksamhet i Stihkeområdet. Vad denna studie främst belyser är dock behovet av en mer genomgripande strategi från statens sida för att komma till rätta med konsekvenserna av Bolidens gruvprojekt och dess följdeffekter. Utifrån senaste årens rättsutveckling torde det numera finnas goda möjligheter för staten att se över sitt ansvar för de skador som framkommit i Stihkeområdet.
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Kløcker Larsen, Rasmus, and Maria Boström. “Låt renen få igen landet som det var”: Konsekvenser av gruvan och vägen på Stihken för Vilhelmina Södra sameby. Stockholm Environment Institute, June 2021. http://dx.doi.org/10.51414/sei2021.007.

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Denna rapport presenterar en studie av Vilhelmina Södra samebys erfarenheter av de konsekvenser som gruvan på Stihken fört med sig, en gruva som drevs av Boliden Mineral AB 1976–1988. Det finns i dag ett stort kunskapsglapp angående vilka de faktiska konsekvenserna är av gruvindustri på samisk markanvändning, inklusive renskötseln. Detta är så vitt vi vet första gången som forskningen empiriskt belyser konsekvenserna av gruvindustrin, och de faktiska utfallen av försöken till efterbehandling, utifrån en samebys egna erfarenheter och kunskap. Studien genomfördes 2019–2020 i ett samarbete mellan samebyn, Svenska Samernas Riksförbund och Stockholm Environment Institute. Datainsamlingen har bestått av arbetsmöten, intervjuer, workshops, dokumentanalys och kartering med stöd av RenGIS och forskning om störningszoner. Fokus i denna rapport ligger på just Vilhelmina Södra samebys erfarenheter och gruvans konsekvenser för andra samebyar eller icke-renskötande samer i området har därför inte inkluderats. Resultaten visar den omfattande påverkan som gruvan haft på samebyn, dels under driftperioden men i högsta grad också efteråt. Under drifttiden förorsakade gruvan stora direkta och indirekta markförluster, med störningar från brytningen och trafiken, damning på betet, blockering av det naturliga flyttstråket och förlust av stora delar av samebyns renar in i Norge eller in på grannbyarnas mark på svensk sida. I nutid handlar de största konsekvenserna om en omfattande störning från besöksnäringen på grund av vägen som drogs i tidigare väglöst land. Detta föranleder i sin tur stort betesbortfall; försämrad djurhälsa och kondition för renen; förhöjd arbetsbelastning, fysiska påfrestningar, och arbetsmiljörisker för renskötarna; ökade kostnader för renskötselaktiviteter; samt förlust av samiska kulturminnen, ökad psykisk påfrestning, försämrade möjligheter för samebyns unga att satsa på renskötseln, och förlust av traditionell kunskap. Dessa forskningsresultat är viktiga för att korrigera vanligt förekommande missuppfattningar i den politiska och offentliga debatten kring gruvindustrin: nämligen att gruvindustrin och renskötseln kan samexistera utan någon större påverkan på renskötseln. De visar också tydligt vem som har bäst kunskap att bedöma riskerna vid en gruvetablering: samebyn identifierade redan på 1960-talet, och det ganska så exakt, de risker som denna studie nu kunnat visa blivit verklighet medan försöken från statens representanter var långt mindre precisa. Exempelvis antog statens experter en total störningszon på 500 meter runt gruvområdet och 100 meter på bägge sidor om vägen. Detta står i stark kontrast till de störningszoner som samebyn faktiskt har upplevt, nämligen upp mot 10 kilometer för gruvan och 1,5 kilometer för vägen. Problemen härrör främst från det faktum att svensk lagstiftning inte ger tillräckligt skydd för samiska rättigheter. De hänger även ihop med statens tvetydiga roll i hanteringen av de intressekonflikter som uppstår när man både har en skyldighet att skydda samiska rättigheter och ska tillgodose olika samhälls- och företagsekonomiska intressen i utvinningen av mineraler. Denna brist på ansvarstagande, som samebyn upplever från statens sida, visar med all tydlighet att den koloniala exploateringen av naturresurserna i Sápmi inte är ett historiskt fenomen utan något som i allra högsta grad fortgår än i dag. Som ett exempel har inga ansträngningar som helst gjorts för att se över huruvida den begränsade ekonomiska ersättningen som staten genomförde under 1960–70 talet verkligen motsvarar de faktiska skador som samebyn fått uthärda. Det finns flera sätt att åtgärda problemen i området vid Stihken. Exempelvis skulle regeringen kunna ge SGU i uppdrag att återställa området från tidigare prospekteringsverksamhet och kommun och länsstyrelse skulle i sin tur kunna ingripa för att hantera besöksnäringen och friluftslivet. Vad denna studie främst belyser är dock behovet av en genomgripande strategi från statens sida för att komma till rätta med konsekvenserna av Bolidens gruvprojekt och dess följdeffekter. Utifrån senaste årens rättsutveckling torde det numera finnas goda möjligheter för staten att se över sitt ansvar för de skador som framkommit på området vid Stihken.
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Fishing Gears of the Cambodian Mekong. Vientiane, Lao PDR: Mekong River Commission Secretariat, March 2003. http://dx.doi.org/10.52107/mrc.akbo7a.

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This catalogue describes more than 150 types of fishing gear used in the Cambodian part of the Mekong River Basin. Types are divided into 16 main categories ranging from hand-capture, scoop and wounding devices to traps and nets. These are divided into 44 secondary categories and 94 tertiary groups. Some 400 names for the different types of gear are given in Khmer (in both Khmer and Latin scripts) and English. Technical descriptions and mentions of target species are accompanied by detailed line drawings and photographs. Charts illustrate the seasons when each type of gear is used in four regions – the Tonle Sap Lake, the Tonle Sap River, the floodplains of the Mekong and Bassac rivers south and east of Phnom Penh, and the upper Mekong in northern Cambodia. Costs are given in local currency based on prices between 1998 and 2000. Gender and legal aspects are also taken into account.
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7

Comparative Analysis on Fuel Consumption Between Two Online Strategies for P2 Hybrid Electric Vehicles: Adaptive-RuleBased (A-RB) vs Adaptive-Equivalent Consumption Minimization Strategy (A-ECMS). SAE International, March 2022. http://dx.doi.org/10.4271/2022-01-0740.

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Hybrid electric vehicles (HEVs) represent one of the main technological options for reducing vehicle CO2 emissions, helping car manufacturers (OEMs) to meet the stricter targets which are set by the European Green Deal for new passenger cars at 80 g CO2/km by 2025. The optimal power-split between the internal combustion engine (ICE) and the electric motor is a challenge since it depends on many unpredictable variables. In fact, HEV improvements in fuel economy and emissions strongly depend on the energy management strategy (EMS) on-board of the vehicle. Dynamic Programming approach (DP), direct methods and Pontryagin’s minimum principle (PMP) are some of the most used methodologies to optimize the HEV power-split. In this paper two online strategies are evaluated: an Adaptive-RuleBased (A-RB) and an Adaptive-Equivalent Consumption Minimization Strategy (A-ECMS). At first, a description of the P2 HEV model is made. Second, the two sub-optimal strategies are described in detail and then implemented on the HEV model to derive the fuel-optimal control strategy managing the power split between the thermal and electric engine to satisfy the driver's power request, including the engine on/off operating mode and the best gear selection. Finally, the two proposed strategies are tested on different driving cycles and then compared to other commercial strategies available in literature, such as the Equivalent Consumption Minimization Strategy (ECMS) and a RuleBased (RB) strategy. The results show that the A-ECMS is more conservative in terms of state of charge (SoC) compared to the A-RB. In fact, in the A-ECMS the SoC is always within the admissible range with considerable margin from the upper and lower limits for tested cycles, while in the A-RB a deep discharge of the battery is allowed. This behavior leads to a better fuel consumption of the A-RB compared to the A-ECMS, both in the WLTC and in the FTP-75 cycle.
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