Comparative Study of Image Denoise Algorithms

Denoising is a pre-processing step in digital image processing system. It is also typical image processing challenges. Many works proposed to solve problem with new approaching. They can be divided into two main categories: spatial-based or transform-based. Some denoising methods apply in both spatial and transform domains. The goal of this paper focuses on reviewing denoise methods, classifying them into different categories, and identifying new trends. Moreover, we do experiments to compare pros, cons of methods in survey

AGING OF WATERBORNE PAINT BASED ON THE ACRYLIC RESIN EMULSION AND ORGANIC PIGMENT

Aging of waterborne paint on the base of acrylic resin emulsion with and without green Luconyl have been investigated by general appearance assessment, adhesion change, FT-IR and discoloration. The obtained results showed that the both of paint-formulas coatings had no cracks, blisters, flacks and there was no change of adhesion during the aging process. However, IR analysis indicated that there were some changes in chemical structures of coating with and without Green Luconyl during aging process. To specify, IR spectrums of initial and aged coating no containing Green Luconyl illustrated aging process led content of O-H and C=C increased significantly but baseline of spectra was fairly unchanged. For coating filled Green Luconyl, IR spectrums’ shape was fairly stable but baseline saw a clear reduce during accelerated weather exposure. Moreover, SEM images indicated that surfaces morphology of samples changed differently depending on in presence of organic pigment. Surface of aged coating without Luconyl saw rougher than surface of coating with Luconyl after aging process. Hence, the weather aging test had more significant influence on paint coating in absence of Luconyl than paint coating in presence of Luconyl. It was explained that the macroradical produced in aging process would attack into conjugated double bonds of Luconyl instead of double bonds of AC-261 leading to aged coating filled Luconyl become more opaque than initial while coating no filled Luconyl had significant changes in chemical structure during aging process. Although this was a hypothesis, it saw a suitable with the obtained results. The paint coating in presence of Luconyl illustrated significant color change, especially, showed the loss of green color while the other paint coating showed slight color change

Analysis of Power and Torque for the IPM Motors with High Flux Density in Stator

The new idea of this paper is to focus on investigating the influence of characteristics on the power and torque of an Interior Permanent Magnet (IPM) motor designed by the Tesla rear-drive. The detail of improvement designs of double V (2V) shape and inverter delta (VI) shape has been proposed for electric vehicles taking a high constant torque in a wide range speed into account. The torque ripple, output power and torque density are developed and evaluated in different topologies via the finite element method. The two-layered rotor structure with the 2V and VI shapes is also designed to give the suitable choices for manufacturing in mass production. For the higher torque density and efficiency, the two-layered 2V or VI magnets of IPM motor with 72 slots/ 8 poles can be adjusted with the sinusoidal step skewing to minimize the torque ripple, harmonic components and back elec- tromotive force. The developed method is performed on the practical problem of the IPM motor of 200 kW −450 Nm, which is applied to the single drive system delivers

An efficient adaptive fuzzy hierarchical sliding mode control strategy for 6 degrees of freedom overhead crane

The paper proposes a new approach to efficiently control a three-dimensional overhead crane with 6 degrees of freedom (DoF). Most of the works proposing a control law for a gantry crane assume that it has five output variables, including three positions of the trolley, bridge, and pulley and two swing angles of the hoisting cable. In fact, the elasticity of the hoisting cable, which causes oscillation in the cable direction, is not fully incorporated into the model yet. Therefore, our work considers that six under-actuated outputs exist in a crane system. To design an efficient controller for the 6 DoF crane, it first employs the hierarchical sliding mode control approach, which not only guarantees stability but also minimizes the sway and oscillation of the overhead crane when it transports a payload to a desired location. Moreover, the unknown and uncertain parameters of the system caused by its actuator nonlinearity and external disturbances are adaptively estimated and inferred by utilizing the fuzzy inference rule mechanism, which results in efficient operations of the crane in real time. More importantly, stabilization of the crane controlled by the proposed algorithm is theoretically proved by the use of the Lyapunov function. The proposed control approach was implemented in a synthetic environment for the extensive evaluation, where the obtained results demonstrate its effectiveness. © 2022 by the authors. Licensee MDPI, Basel, Switzerland

Assessment of the influence of hydraulic and mechanical anisotropy on the fracture initiation pressure in permeable rocks using a complex potential approach

International audienc

Closed-form solution of stress state and stability analysis of wellbore in anisotropic permeable rocks

International audienc

Badanie nad rozkładem naprężeń przed ścianą gdy stosunek urabiania do odzyskania zmienia się w eksploatacji długich ścian przy bardzo grubych pokładach

The extraction with higher cutting height for extra-thick seam is the new research orientation in longwall caving technology. Due to the increase of top coal thickness and of cutting height which leads to the change of cutting/caving height ratio, the rule of roof failure (including top coal caving) and the distribution of stress around the face alter correspondingly. This paper is based on the geological conditions of face 8102 of Tashan-DaTong mine, employing the numerical model by UDEC2D code, analysing the effect of cutting/ caving height ratio on the law of stress distribution ahead of the face. When the ratio of cutting/caving height decreases and the cutting height increases, the results of the research have shown that: (i)- peak stress redistributes further ahead of the face and its value manifestly drops; (ii)- the plastic deformation ahead of face significant increases and the zone of plastic strain also expands. It is therefore concluded that the variation of cutting/caving height ratio results in the redistribution of roof pressure, which contributes to the control of roof failure and face stability.Przy bardzo grubych pokładach, eksploatacja z dużą wysokością to nowy kierunek badań w technologii zawału stropu węgla. Ze względu na grubość warstwy stropu węglowego i zwiększoną wysokość urabiania prowadzi do zmiany stosunku urabiania do odzyskania, co również zmienia regułę zapalenia skał stropowych i zmienia stan rozkładu naprężeń wokół ściany. W artykule, przedstawiono wyniki analizy wpływu stosunku urabiania do uzyskania opierając się na prawie rozkładu obciążenia przed ścianą. Analiza ta została oparta na warunkach geologicznych kopalni 8102 TaSan-DaTong wykorzystując model numeryczny UDEC2D. Wyniki badań pokazują, że wraz ze spadkiem stosunku urabiania do odzyskania, oznacza to wzrost wysokości urabiania, położenie maksymalnego naprężenia jest daleko od ściany, maksymalna wartość naprężeń znacznie spada, zniszczenie plastyczne przed ścianą i stropem gwałtownie rośnie, zwiększa się strefa odkształcenia plastycznego. Dlatego zmiana stosunku urabiania do odzyskania może zmienić stan rozkładu ciśnienia stropowego, co jest korzystne dla procesu niszczenia stropu i kontrolowania stabilności ściany

Combined effect of anisotropy and uncertainty on the safe mud pressure window of horizontal wellbore drilled in anisotropic saturated rock

International audienc

Extend Convergence-Confinement Method for deep tunnels in poroelastic anisotropic medium

This paper is devoted to present a closed-form solution based on the approach of the conventional convergence-confinement method to study the effect of the movement of the tunnel face during the excavation on the stress-strain state of the surrounding medium and the interaction between the ground and the support for a deep tunnel in poroelastic anisotropic medium. In this study, a hydro-mechanical coupling behaviour of the ground at the steady-state of the groundwater flow will be taken into account. The obtained solution could be used as a quick tool to calibrate tunnels in elastic porous medium. Some numerical estimations indicate that, a hydro-mechanical model of the medium should be considered in tunnel design