| 1. |
- Wang, Xiaojie, et al.
(författare)
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A City-Wide Real-Time Traffic Management System : Enabling Crowdsensing in Social Internet of Vehicles
- 2018
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Ingår i: IEEE Communications Magazine. - 0163-6804 .- 1558-1896. ; 56:9, s. 19-25
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Tidskriftsartikel (refereegranskat)abstract
- As an emerging platform based on ITS, SIoV is promising for applications of traffic management and road safety in smart cities. However, the end-to-end delay is large in store-carry-and-forward-based vehicular networks, which has become the main obstacle for the implementation of large-scale SIoV. With the extensive applications of mobile devices, crowdsensing is promising to enable real-time content dissemination in a city-wide traffic management system. This article first provides an overview of several promising research areas for traffic management in SIoV. Given the significance of traffic management in urban areas, we investigate a crowdsensing-based framework to provide timely response for traffic management in heterogeneous SIoV. The participant vehicles based on D2D communications integrate trajectory and topology information to dynamically regulate their social behaviors according to network conditions. A real-world taxi trajectory analysis-based performance evaluation is provided to demonstrate the effectiveness of the designed framework. Furthermore, we discuss several future research challenges before concluding our work.
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| 2. |
- Cao, Pingxiang, et al.
(författare)
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Effect of rake angle on cutting performance during machining of stone-plastic composite material with polycrystalline diamond cutters
- 2019
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Ingår i: Journal of Mechanical Science and Technology. - : Springer. - 1738-494X .- 1976-3824. ; 33:1, s. 351-356
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Tidskriftsartikel (refereegranskat)abstract
- This study investigates the effect of rake angle on cutting performance during machining of stone-plastic composite material with diamond cutters. To that end, an orthogonal cutting experiment was designed, in which stone-plastic composite material was planed by a polycrystalline diamond (PCD) cutter to produce chips. The features studied include cutting forces, cutting heat, chip formation and cutting quality. The conclusions are as follows: Firstly, increased rake angle causes frictional force and resulting force to decrease, promoting an increase in normal force. Secondly, during planing, cutting heat is primarily distributed in the chips, with less retained in the cutting edge, and the least retained in the machined surface. The temperatures of both cutting edge and chip decline with an increase in rake angle. Thirdly, as rake angle increases, chip morphology changes from segmental to curved and then to particle chips, with chip-breaking lengths first increasing and then decreasing. Finally, an increased rake angle leads a more stable cutting process and improved cutting quality. Therefore, with the precondition of blade strength, a diamond cutter with a larger rake angle can be used to machine stone-plastic composite to improve production quality by forming a smoother machined surface.
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| 3. |
- Guo, Xiaolei, et al.
(författare)
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Cutting forces and cutting quality in the up-milling of solid wood using ceramic cutting tools
- 2021
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Ingår i: The International Journal of Advanced Manufacturing Technology. - : Springer. - 0268-3768 .- 1433-3015. ; 114:5-6, s. 1575-1584
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Tidskriftsartikel (refereegranskat)abstract
- Although many studies have focused on the cutting performance of ceramic blades in processing different materials, few have reported on their application in wood processing. Thus, it is necessary to explore the cutting performance of ceramic tools in solid wood machining. The aims of this paper were to evaluate the cutting performance of Al2O3 and Si3N4 ceramic tools in the process of machining Manchurian ash (Fraxinus mandshurica Rupr.) and Chinese fir (Cunninghamia lanceolata) by means of analysing cutting force and surface roughness and to provide guidelines for factories for applying ceramic tools in the manufacture of solid wood furniture. Up-milling tests were conducted for each combination of cutting speed, tool material, and workpiece material, and each combination was replicated five times. Results showed that (1) cutting force and surface roughness decreased with increase of cutting speed and (2) cutting force and surface roughness resulting from using Al2O3 ceramic cutting tools were larger than those of Si3N4 ceramic cutting tools, especially when cutting Manchurian ash with its extractives. Overall, ceramic tools can be used in high-speed cutting of solid wood. Compared with Al2O3 ceramic cutting tools, Si3N4 ceramic cutting tools are more suitable for cutting solid wood, especially those with extractives. Si3N4 ceramic tools provided not only chemical stability, but improved final product quality.
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| 4. |
- Guo, Xiaolei, et al.
(författare)
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Machinability of wood fiber/polyethylene composite during orthogonal cutting
- 2021
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Ingår i: Wood Science and Technology. - : Springer. - 0043-7719 .- 1432-5225. ; 55:2, s. 521-534
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Tidskriftsartikel (refereegranskat)abstract
- Wood fiber/polyethylene composite (WFPEC) is composed of a natural wood fiber and a recyclable polyethylene plastic, which is normally used as an environmental protection composite material. However, better knowledge of chip formation and surface damage mechanism of WFPEC is essential to improve its machinability for extending exterior and interior applications. In this article, machinability of WFPEC was investigated by analyzing the disparity between cutting efficiency and surface quality through a group of orthogonal cutting experiments with change of cutting depth. The chip formation process was recorded by a high-speed camera system with 5000 frames per second. Surface topography was observed by a scanning electron microscope. The results showed that the chip morphology changed from continuous cutting governed by a continuous shearing process under the shallow cutting depth, to a discontinuous cutting governed by plastic fracture under the deep cutting depth ahead of the tool tip. Flattened matrix was the main form of surface topography caused by shallow cutting depth, while matrix-fiber tearing was caused by deep cutting depth. Pullout/fracture and debonding of fibers were related to the fiber orientation angle and the diameter of fiber bundles, but not to the cutting depth. Taken together, the toughness of the workpiece material in the cutting region decreased with the increase in cutting depth. To avoid matrix-fiber tearing, shallow cutting depth should be used during finishing to maintain surface quality. In contrast, pre-cutting can be performed with a deep cutting depth in order to improve the cutting efficiency.
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| 5. |
- Hu, Xiping, et al.
(författare)
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Crowdsourcing for Mobile Networks and IoT
- 2018
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Ingår i: Wireless Communications & Mobile Computing. - : WILEY-HINDAWI. - 1530-8669 .- 1530-8677.
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 6. |
- Jiang, Shangsong, et al.
(författare)
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Cutting Force and Surface Roughness during Straight-Tooth Milling of Walnut Wood
- 2022
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Ingår i: Forests. - : MDPI. - 1999-4907. ; 13:12
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Tidskriftsartikel (refereegranskat)abstract
- Walnut (Juglans regia L.) is widely used in wood furnishings, and machinability is a key factor for improving product quality and enterprise benefits. This work focused on the influence of the rake angle, depth of cut, and cutting speed on the cutting force and machined surface roughness during the straight-tooth milling of walnut. On the basis of the experimental findings, a mathematical model was created using a response surface methodology to determine the relationship between the cutting force and the cutting conditions, as well as the relationship between the surface roughness and the cutting conditions. Variance analysis was used to study the significant contributions of the interactions of various factors and two-level interactions to the cutting force and surface roughness. The optimized combination of milling conditions, resulting in lowest cutting force and surface roughness, was determined to be a rake angle of 5°, a depth of cut of 0.6 mm, and a cutting speed of 45 m/s.
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| 7. |
- Song, Meiqi, et al.
(författare)
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Effects of Tool Tooth Number and Cutting Parameters on Milling Performance for Bamboo–Plastic Composite
- 2023
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Ingår i: Forests. - : MDPI. - 1999-4907. ; 14:2
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Tidskriftsartikel (refereegranskat)abstract
- Cutting force and temperature are critical indicators for improving cutting performance and productivity. This study used an up-milling experiment to ascertain the effect of tool tooth number, cutting speed, and depth on the machinability of bamboo–plastic composite. We focused on the changes in the resultant force and cutting temperature under different milling conditions. A response surface methodology was used to build prediction models for the resultant force and temperature. A verification test was conducted to prove the model’s reliability. The empirical findings suggested that the number of tool teeth had the most significant impacts on both the resultant force and the cutting temperature, followed by the depth of cut and the cutting speed. Moreover, the resultant force and cutting temperature showed increasing trends with decreasing numbers of tool teeth and increasing cut depths. However, cutting speed had a negative relationship with the resultant force and a positive relationship with temperature. We also determined the optimal milling conditions with the lowest force and temperature: four tool teeth, 300 m/min cutting speed, and 0.5 mm depth. This parameter combination can be used in the industrial manufacture of bamboo–plastic composite to improve tool life and manufacturing productivity.
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| 8. |
- Wang, Jinxin, et al.
(författare)
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Machining Properties of Stone-Plastic Composite Based on an Empirically Validated Finite Element Method
- 2023
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Ingår i: Advanced Engineering Materials. - : John Wiley & Sons. - 1438-1656 .- 1527-2648. ; 25:8
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Tidskriftsartikel (refereegranskat)abstract
- High-cutting performance is an essential metric for improving the suitability of materials for industrial applications. Herein, the machining properties of stone-plastic composite are assessed through a finite element method to explore orthogonal cutting behavior by diamond cutters. The key aspects examined in this work are the effects of tool geometry and cutting parameters on the cutting force, temperature, chip formation, von Mises stress, and surface quality finish. Primary findings show that chip continuity increases proportionally with increase in rake angle but decreases with cutting speed and depth. Meanwhile, both cutting stability and surface quality are negatively correlated with cutting speed and depth but positively correlated with rake angle. These results support the adoption of cutting conditions using greater rake angle, higher cutting speed, and shallower cutting depth to obtain higher cutting performance, that is, greater cutting stability and surface quality in the finishing machining of stone-plastic composites.
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| 9. |
- Wei, Hong, et al.
(författare)
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Analysis of Cutting Performance in High Density Fiberboard Milling by Ceramic Cutting Tools
- 2018
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Ingår i: Wood research. - : Slovak Forest Products Research. - 1336-4561. ; 63:3, s. 455-466
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Tidskriftsartikel (refereegranskat)abstract
- In order to study the cutting performance of TiC reinforced Al2O3 ceramic cutting tools in milling high density fiberboard, the effects of cutting parameter on the cutting forces, tool wear and cutting quality were investigated. Under the condition of same average chip thickness, feed per tooth and geometry angles, firstly, the change rate of maximum cutting forces were higher than that of average cutting forces at two different cutting speeds, and the cutting forces at high speed cutting was less than that at low speed cutting. Secondly, the flank wear at high speed cutting was more pronounced than that at low speed cutting, whose abnormal wear were pull-out of grain, cracking, chipping and flanking. Thirdly, the machining quality at high speed cutting was better than that at low speed cutting. Fourthly, the tendencies of cutting forces, tool wear and surface roughness relative to cutting length were similar, but the change rates were different, especially at the initial stage. Finally, high speed cuttingare plausible to use in HDF processing, which not only improves machining quality, but also promotes production efficiency.
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| 10. |
- Yu, Yingyue, et al.
(författare)
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Cutting Power, Temperature, and Surface Roughness: A Multiple Target Assessment of Beech during Diamond Milling
- 2023
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Ingår i: Forests. - : MDPI. - 1999-4907. ; 14:6
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Tidskriftsartikel (refereegranskat)abstract
- Beech wood is a material commonly used for furniture, and cutting performance is the key to improving product quality and enterprise benefits. In this work, beech milling experiments using diamond cutters were carried out, and the changes in cutting power, temperature, and surface roughness were examined using the factor analysis method. The main results of this work are listed as follows: Firstly, a higher cutting speed and depth led to higher cutting power, temperature, and surface roughness. Meanwhile, cutting power and surface roughness were negatively related to the rake angle; however, cutting temperature first increased and then decreased with the increase in rake angle. Furthermore, cutting depth had greatest impact on the cutting power and surface roughness, followed by rake angle and cutting speed. Cutting speed had the greatest contribution to the cutting temperature, followed by cutting depth and rake angle. Only the cutting depth had a significant contribution to both cutting power, temperature, and surface roughness. Finally, optimal cutting parameters were determined to be a rake angle of 15°, cutting speed of 54 m/s, and depth of 0.5 mm. These values best meet the multiple objectives of lower cutting power, temperature, and surface roughness, which relate to superior product quality and enterprise benefits.
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