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101.
Huang  Wei  Luo  Mingyuan  Zhang  Peng  Zha  Yufei 《Multimedia Tools and Applications》2021,80(4):5945-5975
Multimedia Tools and Applications - The pedestrian re-identification problem (i.e., re-id) is essential and pre-requisite in multi-camera video surveillance studies, provided the fact that...  相似文献   
102.
Machine Intelligence Research - One of the most significant challenges in the neuroscience community is to understand how the human brain works. Recent progress in neuroimaging techniques have...  相似文献   
103.
音频大地电磁(AMT)在隧道的工程地质勘察是一种非常有效的方法,它具有不受高阻屏蔽、轻便、探测深度相对较大等优点,在宏观上可以查明隧道地层岩性分界、地质构造及其赋水性。以某隧道音频大地电磁勘察为例,分别对AMT的采集手段、工频干扰去噪、静态校正、反演方法等关键技术问题进行分析,并结合实际资料对该工作区的地层分布、断层及其破碎带的赋水情况等进行分析和解释,在其应用中取得了理想的效果。  相似文献   
104.
The viscous damping coefficient(VDC) of hydraulic actuators is crucial for system modeling,control and dynamic characteristic analysis.Currently,the researches on hydraulic actuators focus on behavior assessment,promotion of control performance and efficiency.However,the estimation of the VDC is difficult due to a lack of study.Firstly,using two types of hydraulic cylinders,behaviors of the VDC are experimentally examined with velocities and pressure variations.For the tested plunger type hydraulic cylinder,the exponential model B=αυ~(-β),(α0,β0)or B=α_1e~(-β_1υ)+α_2e~(-β_2υ)(α_1,α_20,β_1,β_20),fits the relation between the VDC and velocities for a given pressure of chamber with high precision.The magnitude of the VDC decreases almost linearly under certain velocities when increasing the chamber pressure from 0.6 MPa to 6.0 MPa.Furthermore,the effects of the chamber pressures on the VDC of piston and plunge type hydraulic cylinders are different due to different sealing types.In order to investigate the VDC of a plunger type hydraulic actuator drastically,a steady-state numerical model has been developed to describe the mechanism incorporating tandem seal lubrication,back-up ring related friction behaviors and shear stress of fluid.It is shown that the simulated results of VDC agree with the measured results with a good accuracy.The proposed method provides an instruction to predict the VDC in system modeling and analysis.  相似文献   
105.
The serious warpage issues of ultrathin chip-on-flex (UTCOF) assembly induced by mismatched thermal stresses have greatly affected the mechanical stability and reliability of emerging ultrathin chip packaging technology. Currently, a theoretical prediction as a convenient and straightforward approach is still lacked for describing effectively the thermal-mechanical behavior of UTCOF during the adhesive curing and cooling process. In consideration of the adhesive thickness approximating to ultrathin chip and flexible substrate thickness, we develop a layerwise-model of ultrathin chip-adhesive-flex structure under plain strain condition, where the behavior of thick adhesive bonding can be described precisely through increasing the subdivided mathematical plies. Further, the analytical results show that the concave and convex forms of ultrathin chip warpage yield at the end of the curing and cooling process respectively. Meanwhile, the effects of its structure dimensions and material properties are also revealed for discussing a way to relieve the extent of ultrathin chip warpage. Additionally, in order to verify the validity of the theoretical prediction, we also introduce the corresponding numerical technique and experimental method. These results suggest that a kind of rigid and ultrathin flexible substrate such as metal foil should be adopted for small warpage of ultrathin assembly.  相似文献   
106.
Guan  Lei  Yang  Xiangyu  Li  Yu  Shi  Changliang  Yan  Dejun  Huang  Jiayong  Zhang  Lai-Chang 《Journal of Applied Electrochemistry》2021,51(11):1619-1633
Journal of Applied Electrochemistry - In this work, the electrochemical corrosion behaviours of selective laser melted (SLMed) and wrought Ti6Al4V alloys in acid fluoride-containing artificial...  相似文献   
107.
Machining characteristics and surface integrity of advanced ceramics, including alumina, alumina–titania, and yttria partially stabilized tetragonal zirconia, were studied under high speed deep grinding conditions. Material removal mechanisms involved in the grinding processes were explored. The material removal in the grinding of alumina and alumina–titania was dominated by grain dislodgement or lateral cracking along grain boundaries. The removal for zirconia was via both local micro fracture and ductile cutting. It was found that under a feed rate of 500 mm/min and for all the wheel speeds used, an increase in the wheel depth of cut (DOC) from 0.1–2 mm slightly improved the ground surface finish, but greatly prolonged the wheel life. This increase did not deepen the subsurface damage layer for the alumina and alumina–titania, but resulted in a slightly deeper damage layer for the zirconia.  相似文献   
108.
对20G高压锅炉管产生裂纹的原因进行了分析,结果表明是冷拔工艺不当所致。  相似文献   
109.
如何提高模具质量   总被引:2,自引:1,他引:2  
介绍了提高模具质量的基本途径,分析了模具的正确使用与维护对其寿命的影响。  相似文献   
110.
炼厂酮苯装置空冷器因空冷管束腐蚀穿孔被迫停工检修,经取样分析和现场调查,得出结论:溶解氧含量偏高,设备本身存在震动,无盐水质量不稳定及空冷管束选材不当是造成空冷器管束腐蚀穿孔的主要原因,提出有效大的防腐措施。  相似文献   
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