Research on Vibration Characteristics of Large Scale Belt Conveyor and its Application

2014 ◽  
Vol 686 ◽  
pp. 491-496
Author(s):  
Yang Gao
Keyword(s):  
Dynamic Load ◽  
Transverse Vibration ◽  
High Speed ◽  
Large Scale ◽  
Development Trend ◽  
Conveyor Belt ◽  
Lateral Stability ◽  
Belt Conveyor ◽  
Large Capacity ◽  
Main Development

High speed and large capacity belt conveyor is the main development trend. In the design, calculated and used of belt conveyor must be considered the high speed, large capacity, dynamic load. This paper starts from the analysis of conveyor belt transverse vibration. Through calculate transverse vibration natural frequency of conveyor belt, and analyze the lateral stability of belt conveyor.

Research and Design on Long-Distance Large-Capacity and High-Speed Belt Conveyor

2012 ◽  
Vol 538-541 ◽  
pp. 3070-3073
Author(s):  
Jing Ping Liu ◽  
Bao Hua Wang ◽  
Shan Lu
Keyword(s):  
High Speed ◽  
Conveyor Belt ◽  
Belt Conveyor ◽  
Long Distance ◽  
Large Capacity ◽  
Increasing Demand ◽  
Belt Conveyors ◽  
Main Components ◽  
Research And Design

This paper discusses aspects of long distance, large capacity, and high speed belt conveyor design. The study is focused mainly on the whole arrangement and main components configuration of Belt Conveyor, including driving device, conveyor belt, drum and rollers etc. With increasing demand for the long distance, large capacity belt conveyors, its designing and manufacturing level will be improved.

scholarly journals LightningBug ONE: An experiment in high-throughput digitization of pinned insects

2019 ◽  
Vol 3 ◽  
Author(s):  
Mark Hereld ◽  
Nicola Ferrier
Keyword(s):  
Natural History ◽  
Character Recognition ◽  
Optical Character Recognition ◽  
High Speed ◽  
Large Scale ◽  
Average Rate ◽  
Large Fraction ◽  
Conveyor Belt ◽  
Production Operation ◽  
Camera System

Digital technology presents us with new and compelling opportunities for discovery when focused on the world's natural history collections. The outstanding barrier to applying existing and forthcoming computational methods for large-scale study of this important resource is that it is (largely) not yet in the digital realm. Without development of new and much faster methods for digitizing objects in these collections, it will be a long time before these data are available in digital form. For example, methods that are currently employed for capturing, cataloguing, and indexing pinned insect specimen data will require many tens of years or more to process collections with millions of dry specimens, and so we need to develop a much faster pipeline. In this paper we describe a capture system capable of collecting and archiving the imagery necessary to digitize a collection of circa 4.5 million specimens in one or two years of production operation. To minimize the time required to digitize each specimen, we have proposed (Hereld et al. 2017) developing multi-camera systems to capture the pinned insect and its accompanying labels from many angles in a single exposure. Using a sampling (21 randomly drawn drawers, totalling 5178 insects) of the 4.5 million specimens in the collection at the Field Museum of Natural History, we estimated that a large fraction of that collection (97.6% +/- 2.2%) consists of pinned insects with labels that are visible from one angle or another without requiring adjustment or removal of elements on the pin. In this situation a multi-camera system with enough angular coverage could provide imagery for reconstructing virtual labels from fragmentary views taken from different directions. Agarwal et al. (2018) demonstrated a method for combining these multiple views into a virtual label that could be transcribed by automated optical character recognition software. We have now designed, built and tested a prototype snapshot 3D digitization station to allow rapid capture of multi-view imagery for automated capture of pinned insect specimens and labels. It consists of twelve very small and light 8-megapixel cameras (Fig. 1), each controlled by a small dedicated computer. The cameras are arrayed around the target volume, six on each side of the sample feed path. Their positions and orientations are fixed by a 3D-printed scaffolding designed for the purpose. The twelve camera controllers and a master computer are connected to a dedicated high-speed data network over which all of the coordinating control signals and returning images and metadata are passed. The system is integrated with a high-performance object store that includes a database for metadata and the archived images comprising each snapshot. The system is designed so that it can be readily extended to include additional or different sensors. The station is meant to be fed with specimens by a conveyor belt whose motion is coordinated with the exposure of the multi-view snapshots. In order to test the performance of the system we added a recirculating specimen feeder designed expressly for this experiment. With it integrated into the system in place of a conventional conveyor belt we are able to provide a continuous stream of targets for the digitization system to facilitate long tests of its performance and robustness. We demonstrated the ability to capture data at a peak rate of 1400 specimens per hour and an average rate of 1000 specimens per hour over the course of a sustained 6 hour run. The dataset (Hereld and Ferrier 2018) collected in this experiment provides fodder for the further development of algorithms for the offline reconstruction and automatic transcription of the label contents.

FEM based approach for development of a new high-speed load model for railway bridges

2021 ◽  
Author(s):  
Alois Vorwagner ◽  
Maciej Kwapisz ◽  
Rainer Flesch ◽  
Antonia M. Kohl ◽  
Andrei Firus ◽  
...  
Keyword(s):  
Dynamic Load ◽  
High Speed ◽  
Large Scale ◽  
International Project ◽  
Vehicle Speed ◽  
Load Bearing Capacity ◽  
Railway Bridges ◽  
Load Model ◽  
Speed Increase ◽  
Existing Bridges

<p>The high-speed load model (HSLM), developed more than 20 years ago, is defined in the code "EN 1991-2" for a dynamic analysis of railway bridges - with respect to ballast destabilisation - within lines with a vehicle speed of more than 120 km/h. The compliance with the (dynamic) load bearing capacity and the serviceability acceleration must be verified for designing new bridges and assessing existing bridges, especially if a speed increase on the railroad is intended. New vehicle types, which are not always covered by the standardised load model, must be examined additionally. This leads to a clear and an urgent need for a revision of the existing high-speed load model. Within this paper, a large-scale dynamic FEM computation including 17 million train passages is presented as a basis for developing a new standard-compliant dynamic load model within the ongoing international project, commissioned by the German EBA (Federal Railway Authority).</p>

Recent Patents on the Angular Contact Ball Bearing of High-Speed Motorized Spindle

2020 ◽  
Vol 13 ◽  
Author(s):  
Yudong Bao ◽  
Linkai Wu ◽  
Yanling Zhao ◽  
Chengyi Pan
Keyword(s):  
High Speed ◽  
Ball Bearing ◽  
Rapid Development ◽  
Ceramic Materials ◽  
Development Trend ◽  
Numerical Control ◽  
Angular Contact Ball Bearing ◽  
Practical Applications ◽  
High Speed Cutting ◽  
Advantages And Disadvantages

Background:: Angular contact ball bearings are the most popular bearing type used in the high speed spindle for machining centers, The performance of the bearing directly affects the machining efficiency of the machine tool, Obtaining a higher value is the direction of its research and development. Objective:: By analyzing the research achievements and patents of electric spindle angular contact bearings, summarizing the development trend provides a reference for the development of electric spindle bearings. Methods:: Through the analysis of the relevant technology of the electric spindle angular contact ball bearing, the advantages and disadvantages of the angular contact ball bearing are introduced, and the research results are combined with the patent analysis. Results:: With the rapid development of high-speed cutting and numerical control technology and the needs of practical applications, the spindle requires higher and higher speeds for bearings. In order to meet the requirements of use, it is necessary to improve the bearing performance by optimizing the structure size and improving the lubrication conditions. Meanwhile, reasonable processing and assembly methods will also have a beneficial effect on bearing performance. Conclusion:: With the continuous deepening of bearing technology research and the use of new structures and ceramic materials has made the bearing's limit speed repeatedly reach new highs. The future development trend of high-speed bearings for electric spindles is environmental protection, intelligence, high speed, high precision and long life.

Review of Research on Hydrostatic Bearings

2020 ◽  
Vol 13 ◽  
Author(s):  
Xiaodong Yu ◽  
Yu Wang ◽  
Junfeng Wang ◽  
Wenkai Zhou ◽  
Hongwei Bi ◽  
...  
Keyword(s):  
High Speed ◽  
Static Pressure ◽  
Development Trend ◽  
Cnc Machining ◽  
Pressure Effects ◽  
Cnc Machine Tools ◽  
Future Research ◽  
Theoretical Formula ◽  
Hydrostatic Bearing ◽  
Hydrostatic Bearings

Background: Hydrostatic bearings have the advantages of strong bearing capacity, good stability, small friction coefficient and long life. The performance of liquid hydrostatic bearings directly affect the accuracy and efficiency of CNC machining equipment. The performance is conducive to the development of CNC machine tools towards high speed and heavy load, so it is necessary to sort out and summarize the existing research results. Objective: This study summarizes the current development status of hydrostatic bearings and explains the development trend of hydrostatic bearings. Methods: According to the recently published journal articles and patents, the recent experimental research on hydrostatic thrust bearings is summarized. This paper summarizes many factors that affect the performance of hydrostatic bearings, and discusses the causes of various factors on hydrostatic bearings. Finally, future research on hydrostatic bearings is presented. Results: The study discusses experimental methods, simulation processes, and experimental results. Conclusion: This study can produce dynamic and static pressure effects by changing the structure of the oil cavity of the hydrostatic bearing. This effect can make up for the static pressure loss. By improving the theoretical formula and mathematical model and proposing a new simulation method, the accuracy of the hydrostatic bearing simulation is satisfied; the future development trend of the hydrostatic bearing is proposed.

Do elite soccer players cover longer distance when losing? Differences between attackers and defenders

2020 ◽  
pp. 174795412098227
Author(s):  
Carlos Lago-Peñas ◽  
Anton Kalén ◽  
Miguel Lorenzo-Martinez ◽  
Roberto López-Del Campo ◽  
Ricardo Resta ◽  
...  
Keyword(s):  
New York ◽  
High Speed ◽  
Large Scale ◽  
Tracking System ◽  
Soccer Players ◽  
Running Performance ◽  
Situational Variables ◽  
Total Distance ◽  
Professional Soccer ◽  
Score Line

This study aimed to evaluate the effects playing position, match location (home or away), quality of opposition (strong or weak), effective playing time (total time minus stoppages), and score-line on physical match performance in professional soccer players using a large-scale analysis. A total of 10,739 individual match observations of outfield players competing in the Spanish La Liga during the 2018–2019 season were recorded using a computerized tracking system (TRACAB, Chyronhego, New York, USA). The players were classified into five positions (central defenders, players = 94; external defenders, players = 82; central midfielders, players = 101; external midfielders, players = 72; and forwards, players = 67) and the following match running performance categories were considered: total distance covered, low-speed running (LSR) distance (0–14 km · h−1), medium-speed running (MSR) distance (14–21 km · h−1), high-speed running (HSR) distance (>21 km · h−1), very HSR (VHSR) distance (21–24 km · h−1), sprint distance (>24 km · h−1) Overall, match running performance was highly dependent on situational variables, especially the score-line condition (winning, drawing, losing). Moreover, the score-line affected players running performance differently depending on their playing position. Losing status increased the total distance and the distance covered at MSR, HSR, VHSR and Sprint by defenders, while attacking players showed the opposite trend. These findings may help coaches and managers to better understand the effects of situational variables on physical performance in La Liga and could be used to develop a model for predicting the physical activity profile in competition.

scholarly journals 1.5 °C degrowth scenarios suggest the need for new mitigation pathways

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Lorenz T. Keyßer ◽  
Manfred Lenzen
Keyword(s):  
Technological Change ◽  
High Speed ◽  
Large Scale ◽  
High Energy ◽  
Climate Mitigation ◽  
Intergovernmental Panel ◽  
Economic Output ◽  
Integrated Assessment Modelling ◽  
Negative Emissions ◽  
Energy Emissions

Abstract1.5  °C scenarios reported by the Intergovernmental Panel on Climate Change (IPCC) rely on combinations of controversial negative emissions and unprecedented technological change, while assuming continued growth in gross domestic product (GDP). Thus far, the integrated assessment modelling community and the IPCC have neglected to consider degrowth scenarios, where economic output declines due to stringent climate mitigation. Hence, their potential to avoid reliance on negative emissions and speculative rates of technological change remains unexplored. As a first step to address this gap, this paper compares 1.5  °C degrowth scenarios with IPCC archetype scenarios, using a simplified quantitative representation of the fuel-energy-emissions nexus. Here we find that the degrowth scenarios minimize many key risks for feasibility and sustainability compared to technology-driven pathways, such as the reliance on high energy-GDP decoupling, large-scale carbon dioxide removal and large-scale and high-speed renewable energy transformation. However, substantial challenges remain regarding political feasibility. Nevertheless, degrowth pathways should be thoroughly considered.

scholarly journals Contributions of Vegetation Greening and Climate Change to Evapotranspiration Trend after Large-Scale Vegetation Restoration on the Loess Plateau, China

Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1755
Author(s):  
Shuo Wang ◽  
Chenfeng Cui ◽  
Qin Dai
Keyword(s):  
Climate Change ◽  
Loess Plateau ◽  
Large Scale ◽  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Potential Evapotranspiration ◽  
Development Trend ◽  
Future Trend ◽  
Natural Ecosystem ◽  
The Loess Plateau

Since the early 2000s, the vegetation cover of the Loess Plateau (LP) has increased significantly, which has been fully recorded. However, the effects on relevant eco-hydrological processes are still unclear. Here, we made an investigation on the changes of actual evapotranspiration (ETa) during 2000–2018 and connected them with vegetation greening and climate change in the LP, based on the remote sensing data with correlation and attribution analysis. Results identified that the average annual ETa on the LP exhibited an obvious increasing trend with the value of 9.11 mm yr−1, and the annual ETa trend was dominated by the changes of ETa in the third quarter (July, August, and September). The future trend of ETa was predicted by the Hurst exponent. Partial correlation analysis indicated that annual ETa variations in 87.8% regions of the LP were controlled by vegetation greening. Multiple regression analysis suggested that the relative contributions of potential evapotranspiration (ETp), precipitation, and normalized difference vegetation index (NDVI), to the trend of ETa were 5.7%, −26.3%, and 61.4%, separately. Vegetation greening has a close relationship with the Grain for Green (GFG) project and acts as an essential driver for the long-term development trend of water consumption on the LP. In this research, the potential conflicts of water demanding between the natural ecosystem and social-economic system in the LP were highlighted, which were caused by the fast vegetation expansion.

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