Film Damage Overlay Download
Raquel Acosta
Film artifacts and FX are scans and digital effects that replicate film imperfections such as scratches, dust, and flickers, which you can overlay on digital footage to create an authentic vintage look.
Research on structural impact detection has been ongoing for many years [5,6,7,8]: Kim et al. [9,10] developed an iterative regularization method to reconstruct the impact force on a graphite/epoxy platform using polyvinylidene fluoride (PVDF) sensors. Wu et al. [11] subsequently presented an optimized technique which identified the impact force and estimated the impact location for isotropic plates by using strain gauge signals, and Shih et al. [12] studied the impact process based on the spectral analysis of acoustic emission signals. Likewise, research on impact-induced damage have also been intensely studied in recent years [13,14,15]: Santosa et al. [16] detected the impact damage on fiberglass composite plates based on surface lava wave propagation, and Kim et al. [17] utilized wavelet-based approach and short-time Fourier transform (STFT) to detect impact damage in composite laminates. Lastly, impact damage detection in concrete structures has become a focus in recent research: Song et al. [18] monitored and evaluated impact damage on bridges due to high-speed vehicle collision using embedded piezoceramic transducers. Demi et al. [19] also embedded piezoceramic transducers in concrete structures, and devised a structural damage indication and quantification method based on root-mean-square deviation method. Jeon et al. [20] investigated the low velocity impact and delamination buckling behavior of composite laminates with embedded optical fibers. Minakuchi et al. [21] developed a fiber-optic-based sensing system to monitor the impact damage of a large-scale Carbon Fiber Reinforced Polymer (CFRP) structure. Based on comparative vacuum monitoring (CVM), and Brillouin-based distributed strain measurement, damage areas can be effectively identified.
Engineering cementitious composites (ECC) has gained popularity in infrastructure construction due to its unique cracking behavior [22], high toughness and energy absorption ability [23], which is approximately 500 times larger than conventional concrete or fiber-reinforced concrete [24], and better shearing resistance [25]. In 1998, Li et al. [26] developed polyvinyl alcohol fiber reinforced engineering cementitious composite (PVA-ECC) with a high tensile strain capacity [27], high compressive strength at early stage [28], and a strong ability to absorb energy [29,30,31]. The high tensile performance of PVA-ECC enables the material to be used as a cast-in-place bridge panel [32], and the high energy absorption characteristics makes PVA-ECC desirable to counter seismic effects on high-rise buildings [33,34]. Furthermore, PVA-ECC can also be used to repair the surface of retaining walls, channels, and viaducts [35]. Thus, PVA-ECC materials have become widespread in bridges and large infrastructure developments. However, the study of impact-induced damage on PVA-ECC structures has not garnered widespread study; specifically, the monitoring of crack formation and development of PVA-ECC beams and columns under impact loads lack detailed studies.
Furthermore, because PVDF material is used as sensor in this paper, the applied external electric field, viz., E3 is zero. Therefore, the generated electrical charge of PVDF thin-film sensor can be expressed as,
Engine bearings are amongst the most critical components of an internal combustion engine that support and allow smooth rotation of the crankshaft. They are designed to operate under hydrodynamic lubrication condition where the bearing and shaft surface are separated by a thick lubricant film. However, they also occasionally operate under mixed and boundary lubrication conditions particularly during starting, stopping and load, speed and temperature variations. Under these conditions, tribological performance of bearing materials is crucial for the satisfactory performance of theengine. Traditionally, the most extensively used engine bearing materials have been Copper-Lead (Cu-Pb) based linings and Pb based overlays because of the friction reducing properties of Pb. However, due to the adverse health and environmental impact of Pb, there is growing emphasis on restricting the usage of Pb in engine bearings. Owing to this, new Pb-free bearing materials that provide at least comparable or superior tribological performance to that of Pb containing materials are being developed. Someof these materials have already been introduced in engine bearing applications. There are, however, only few research results in the open literature as to how these new engine bearing materials would perform in mixed and boundary lubricated conditions. The objective of this work is to evaluate and understand the tribological performance of selected Pb-free engine bearing materials and compare their performance with that of the traditional Pb-containing material. To understand the damage mechanisms in thetraditional Pb-containing bearings, a full set of main and connecting rod bearings from field test run in Euro V truck engines in long haulage application with European diesel fuel and with slightly longer oil drainage interval were investigated. Furthermore, laboratory tests on Pb-free engine bearings with different compositions of lining and overlay materials were carried out with a block-on-ring test set up in order to evaluate their tribological performance. For this study, aluminum-tin (Al-Sn) based lining withno overlay; Cu-based linings with overlay of polyamide-imide (PAI) containing MoS, 2 and graphite, Al-Sn based overlay and Sn based overlay were studied. Cu-Pb lining with Pb-based overlay was also studied as a reference.Investigations on a full set of main bearings and connecting rod bearings from field test revealed that the major damage mechanisms were 3-body abrasive wear leading to exposure of lining material, flaking of overlay material due to surface fatigue, formation of compound layer composed of Sn, Cu and Ni and cavitation damage.Laboratory tests on Pb-free bearing materials have shown that Al-Sn based lining with no overlay shows higher friction than the other materials at lower rotational speed. For Al-Sn based lining and Pb-based overlay materials, the decrease in friction is relatively sharp as rotational speed increases compared with the PAI based overlay. Test samples with overlay of PAI containing graphite and MoS 2 exhibited better friction and wear properties than Al-Sn based and Pb-based materials. Under steady-state conditions,Pb-containing bearing material shows higher wear and Al-Sn based material hasshown higher friction. In addition, Sn-based and Pb-based overlays have shownsimilar friction behaviour when rotational speed is varied. For relatively longer test durations, samples with Sn overlay exhibited comparable friction and wear with that of Pb-based overlay material.
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