Uneven illumination surface defects inspection based on convolutional neural network

Surface defect inspection based on machine vision is often affected by uneven illumination. In order to improve the inspection rate of surface defects inspection under uneven illumination condition, this paper proposes a method for detecting surface image defects based on convolutional neural network, which is based on the adjustment of convolutional neural networks, training parameters, changing the structure of the network, to achieve the purpose of accurately identifying various defects. Experimental on defect inspection of copper strip and steel images shows that the convolutional neural network can automatically learn features without preprocessing the image, and correct identification of various types of image defects affected by uneven illumination, thus overcoming the drawbacks of traditional machine vision inspection methods under uneven illumination

Prediction of Stable Ground-State Lithium Polyhydrides under High Pressures

Hydrogen-rich compounds are important for understanding the dissociation of dense molecular hydrogen, as well as searching for room temperature Bardeen-Cooper-Schrieffer (BCS) superconductors. A recent high pressure experiment reported the successful synthesis of novel insulating lithium polyhydrides when above 130 GPa. However, the results are in sharp contrast to previous theoretical prediction by PBE functional that around this pressure range all lithium polyhydrides (LiHn (n = 2-8)) should be metallic. In order to address this discrepancy, we perform unbiased structure search with first principles calculation by including the van der Waals interaction that was ignored in previous prediction to predict the high pressure stable structures of LiHn (n = 2-11, 13) up to 200 GPa. We reproduce the previously predicted structures, and further find novel compositions that adopt more stable structures. The van der Waals functional (vdW-DF) significantly alters the relative stability of lithium polyhydrides, and predicts that the stable stoichiometries for the ground-state should be LiH2 and LiH9 at 130-170 GPa, and LiH2, LiH8 and LiH10 at 180-200 GPa. Accurate electronic structure calculation with GW approximation indicates that LiH, LiH2, LiH7, and LiH9 are insulative up to at least 208 GPa, and all other lithium polyhydrides are metallic. The calculated vibron frequencies of these insulating phases are also in accordance with the experimental infrared (IR) data. This reconciliation with the experimental observation suggests that LiH2, LiH7, and LiH9 are the possible candidates for lithium polyhydrides synthesized in that experiment. Our results reinstate the credibility of density functional theory in description H-rich compounds, and demonstrate the importance of considering van der Waals interaction in this class of materials.Comment: 34 pages, 15 figure

Imaginary potential and entropic force in non-commutative plasma

We study the imaginary potential and entropic force with respect to a heavy quarkonium in non-commutative N=4 super Yang-Mills (SYM) plasma at strong coupling. We compute the two quantities both along commutative as well as the non commutative coordinates of the brane. It is found that the two methods give the same result: non-commutativity reduces quarkonia dissociation

Antioxidant and anti-inflammatory effects of rhamnazin on lipopolysaccharide-induced acute lung injury and inflammation in rats

Background: Acute Lung Injury (ALI) results into severe inflammation and oxidative stress to the pulmonary tissue. Rhamnazin is a natural flavonoid and known for its antioxidant and anti-inflammatory properties.Materials and methods: The antioxidative and anti-inflammatory properties rhamnazin were tested for protection against the acute lung injury. We investigated whether rhamnazin improves the lipopolysaccharide (LPS)-induced ALI in an animal model (rat). We also studied the probable molecular mechanism of action of rhamnazin. Rhamnazin was injected intraperitoneally (i.p.) (5, 10 and 20 mg/kg) two days before intratracheal LPS challenge (5mg/kg). The changes in lung wet-to-dry weight ratio, LDH activity, pulmonary histopathology, BALF protein concentration, MPO activity, oxidative stress, cytokine production were estimated.Results: The results showed a significant attenuation of all the inflammatory parameters and a marked improvement in the pulmonary histopathology in the animal groups pretreated with rhamnazin. The rhamnazin pretreated group also showed activation of Nrf2 pathway and attenuation of ROS such as H2O2, MDA and hydroxyl ion. These results indicated that rhamnazin could attenuate the symptoms of ALI in rats due to its strong antioxidant and anti-inflammatory properties.Conclusion: The results strongly demonstrated that rhamnazin provides protection against LPS-induced ALI. The underlying mechanisms of its anti-inflammatory action may include inhibition of Nrf2 mediated antioxidative pathway.Keywords: acute lung injury, inflammation, cytokine, BALF, flavonoi

Back reaction effects on the imaginary potential of quarkonia in heavy quark cloud

Applying the AdS/CFT correspondence, we investigate the effect of back reaction on the imaginary part of heavy quarkonia potential in strongly coupled N=4 supersymmetric Yang-Mills (SYM) plasma. The back reaction considered here arises from the inclusion of static heavy quarks uniformly distributed over N=4 SYM plasma. It is shown that the presence of back reaction reduces the absolute value of the imaginary potential thus decreasing the thermal width. Furthermore, the results imply that back reaction enhances the quarkonia dissociation

A Proposed Priority Pushing and Grasping Strategy Based on an Improved Actor-Critic Algorithm

The most basic and primary skills of a robot are pushing and grasping. In cluttered scenes, push to make room for arms and fingers to grasp objects. We propose a modified Actor-Critic (A-C) framework for deep reinforcement learning, Cross-entropy Softmax A-C (CSAC), and use the Prioritized Experience Replay (PER) based on the theoretical foundation and main methods of deep reinforcement learning, combining the advantages of algorithms based on value functions and policy gradients. The grasping model is trained using self-supervised learning to achieve end-to-end mapping from image to propulsion and grasping action. A vision module and an action module have been created out of the entire algorithm framework. The prioritized experience replay is improved to further improve the CSAC-PER algorithm for model sample diversity and robot exploration performance during robot grasping training. The experience replay buffer is dynamically sampled using the prior beta distribution and the dynamic sampling algorithm based on the beta distribution (CSAC-beta) is proposed based on the CSAC algorithm. Despite its low initial efficiency, the experimental simulation results show that the CSAC-beta algorithm eventually achieves good results and has a higher grasping success rate (90%)

ANTIOXIDANT AND ANTI-INFLAMMATORY EFFECTS OF RHAMNAZIN ON LIPOPOLYSACCHARIDE-INDUCED ACUTE LUNG INJURY AND INFLAMMATION IN RATS

Background: Acute Lung Injury (ALI) results into severe inflammation and oxidative stress to the pulmonary tissue. Rhamnazin is a natural flavonoid and known for its antioxidant and anti-inflammatory properties. Materials and methods: The antioxidative and anti-inflammatory properties rhamnazin were tested for protection against the acute lung injury. We investigated whether rhamnazin improves the lipopolysaccharide (LPS)-induced ALI in an animal model (rat). We also studied the probable molecular mechanism of action of rhamnazin. Rhamnazin was injected intraperitoneally (i.p.) (5, 10 and 20 mg/kg) two days before intratracheal LPS challenge (5mg/kg). The changes in lung wet-to-dry weight ratio, LDH activity, pulmonary histopathology, BALF protein concentration, MPO activity, oxidative stress, cytokine production were estimated. Results: The results showed a significant attenuation of all the inflammatory parameters and a marked improvement in the pulmonary histopathology in the animal groups pretreated with rhamnazin. The rhamnazin pretreated group also showed activation of Nrf2 pathway and attenuation of ROS such as H2O2, MDA and hydroxyl ion. These results indicated that rhamnazin could attenuate the symptoms of ALI in rats due to its strong antioxidant and anti-inflammatory properties. Conclusion: The results strongly demonstrated that rhamnazin provides protection against LPS-induced ALI. The underlying mechanisms of its anti-inflammatory action may include inhibition of Nrf2 mediated antioxidative pathway

Accepted and presented at The Design of Medical Devices Conference (DMD2016)

The ankle plays an important role in human walking. Biomechanical studies show that the ankle generates more power than hip and knee in walking Motivated by this reality, researchers have expended a significant amount of efforts in creating energetically active (i.e., powered) TT prostheses. Typical examples include the multiple prototypes developed by the MIT Biomechatronics Group (e.g., Ref. [2]), the SPARKy prosthesis, and the Vanderbilt transtibial prosthesis. These prostheses are all powered with electric motors, augmented with mechanical springs to simulate the elastic characteristics of the biological ankle. For example, the prosthesis design by Au et al. uses springs in series with the electric motor to form a series elastic actuator, and an additional spring is used to simulate the energy storage-and-return feature in the ankle loading and push-off Compared with the actuation approaches in the aforementioned works, pneumatic actuation is a strong competitor with its multiple advantages. Pneumatic actuators have higher power density than electric motors in general. More importantly, a pneumatic actuator features a physically existing elasticity that can be adjusted via pressure regulation. As such, a pneumatically actuated prosthesis has a potential of simulating the elasticity of the biological ankle without using mechanical springs, significantly simplifying the system design. However, such potential has not been utilized in existing pneumatic TT prostheses (e.g., Ref. [3]). In this paper, a new control approach, namely, variable series elasticity control (VSEC), is presented, which provides effective control of a pneumatically actuated TT prosthesis, leveraging the aforementioned elasticity in pneumatic actuators. Methods The powered TT prosthesis that serves as the basis of this work is the Alabama Powered Prosthetic Limb-Ankle (APPL-A) To model the joint elasticity, the linear stiffness of the pneumatic cylinder can be expressed as where K is the stiffness, R is the universal gas constant, T is the air temperature, L is the stroke, x is the displacement with respect to the middle point of the stroke, L da and L db are the dead lengths of chambers a (rodless chamber) and b (chamber with rod), respectively, and m a and m b are the air masses in chambers a and b, respectively. It can be clearly observed from this equation that the actuator stiffness is a function of chamber air masses m a and m b . Similar to the stiffness, the equilibrium point x e can also be expressed as a function of the chamber air masses where A r is the rod cross-sectional area. Combining Eqs. (1) and (2), the air masses can be calculated based on a set of desired stiffness-equilibrium point Subsequently, the desired pressure is compared with the measured chamber pressure to determine the initial valve commands: open the chamber to pneumatic supply if the measured pressure is lower than desired, otherwise open the chamber to exhaust. When the desired pressure is reached, close the chamber until the state machine transitions to the next phase. Note that the attainable chamber pressure is limited to the range as defined by the supply pressure (150 psi, or 1034 kPa, as dictated by the maximum pressure rating of the control valve, VQ1300K-5B1, SMC Corporation, Tokyo, Japan) and atmosphere pressure. As such, specia

Effect of sanhuanghuoxue decoction on the treatment of chronic renal failure

The aim of this study was to investigate the efficacy of sanhuanghuoxue decoction in the treatment of chronic renal failure by examining the changes in serum creatinine and blood urine nitrogen using rat models. Compared with the control group, which was treated by coated aldehyde oxystarch, the group treated by sanhuanghuoxue showed remarkable decrease in serum creatinine and blood urine nitrogen. The difference was found statistically significant.