To address the issue of premature convergence and slow convergence rate in three-dimensional (3D) route planning of unmanned aerial vehicle (UAV) low-altitude penetration,a novel route planning method was proposed.Fir...To address the issue of premature convergence and slow convergence rate in three-dimensional (3D) route planning of unmanned aerial vehicle (UAV) low-altitude penetration,a novel route planning method was proposed.First and foremost,a coevolutionary multi-agent genetic algorithm (CE-MAGA) was formed by introducing coevolutionary mechanism to multi-agent genetic algorithm (MAGA),an efficient global optimization algorithm.A dynamic route representation form was also adopted to improve the flight route accuracy.Moreover,an efficient constraint handling method was used to simplify the treatment of multi-constraint and reduce the time-cost of planning computation.Simulation and corresponding analysis show that the planning results of CE-MAGA have better performance on terrain following,terrain avoidance,threat avoidance (TF/TA2) and lower route costs than other existing algorithms.In addition,feasible flight routes can be acquired within 2 s,and the convergence rate of the whole evolutionary process is very fast.展开更多
A high-entropy alloy–ceramic gradient composite of TiC–TiB_2/75vol% Al_(0.3) CoCrFe Ni was successfully prepared by combustion synthesis under an ultra-high gravity field, which is a low-cost method with high effici...A high-entropy alloy–ceramic gradient composite of TiC–TiB_2/75vol% Al_(0.3) CoCrFe Ni was successfully prepared by combustion synthesis under an ultra-high gravity field, which is a low-cost method with high efficiency. The ceramic particles were gradient distributed in the Al_(0.3) CoCrFe Ni matrix, and the hardness of the composite material gradually decreased along the thickness direction. The anti-penetration performance of the gradient composites was simulated using the ANSYS/LS-DYNA explicit simulation program. The results demonstrate that the distribution of the ceramic particles strongly affected the mechanical properties and the anti-penetration performance of the composites. With the same total ceramic volume fraction, the gradient composites exhibit better anti-penetration performance than the corresponding ceramic–metal interlayer composites. The more uneven the ceramic distribution, the greater the elastic modulus and yield stress of the surface layer and, thus, the better the anti-penetration performance.展开更多
This paper compares the penetration capabilities of the same type anti-ship missiles with millimeter wave(MMW)seeker and centimeter wave seeker,and constructs mathematical models of penetration probability and saturat...This paper compares the penetration capabilities of the same type anti-ship missiles with millimeter wave(MMW)seeker and centimeter wave seeker,and constructs mathematical models of penetration probability and saturation attack number for all anti-ship missiles used in the countermeasure system,according to the rule which makes the ship-borne air defence system oppase as far as possible and equally,and combining the actual combat situation.It can be seen,from analysis of the countermeasure process between anti-ship missile and surface naval ship,that for the same type of anti-ship missile with different seekers,the main influence on the penetration capability is from electronic jamming system.Based on the built model,the penetration capabilities of the same type anti-ship missiles with MMW and centimeter wave seekers are simulated.The simulated results show that the penetration capability of MMW seeker is slightly better than that of the centimeter wave seeker and its saturation attack number is also influenced by the discovering probability greatly.Finally,some suggestions to get superior penetration effect are given for a commander to choose seeker type suitably.展开更多
We study the two-dimensional above-barrier penetration and the sub-barrier tunneling of non-relativistic particles and photons, described in the quasi-monochromatic approximation by simple plane waves. Our scheme repr...We study the two-dimensional above-barrier penetration and the sub-barrier tunneling of non-relativistic particles and photons, described in the quasi-monochromatic approximation by simple plane waves. Our scheme represents the motion from the left free-motion zero-potential region to the right zero-potential region through the intermediate region with a one-dimensional rectangular potential barrier along the axis, normal to the both parallel interfaces between all three regions, and with the zero potential along the axis, parallel to the those interfaces. We have firstly obtained the analytical expressions for the infinite series of multiple internal and external reflections and also of multiple transmitted waves of particles and photons, with equal shifts between them along the interfaces for the above-barrier penetration and with various shifts between them in the case of the sub-barrier tunneling. Finally the Hartman and Fletcher effect for any transmitted wave is established.展开更多
Based on the analysis for the interception process of ship-to-air missile system to the anti-ship missile stream, the antagonism of ship-to-air missile and anti-ship missile stream was modeled by Monte Carlo method. T...Based on the analysis for the interception process of ship-to-air missile system to the anti-ship missile stream, the antagonism of ship-to-air missile and anti-ship missile stream was modeled by Monte Carlo method. This model containing the probability of acquiring anti-ship missile, threat estimation, firepower distribution, interception, effectiveness evaluation and firepower turning, can dynamically simulate the antagonism process of anti-ship missile attack stream and anti-air missile weapon system. The anti-ship missile's saturation attack stream for different ship-to-air missile systems can be calculated quantitatively. The simulated results reveal the relations among the anti-ship missile saturation attack and the attack intensity of anti-ship missile, interception mode and the main parameters of anti-air missile weapon system. It provides a theoretical basis for the effective operation of anti-ship missile.展开更多
Objective: Hemp seed oil is perfect for most skin types;it moisturizes skin and protects it from inflammation, oxidation, and other causes of aging. The problem is that the Hemp oil-based products do not penetrate the...Objective: Hemp seed oil is perfect for most skin types;it moisturizes skin and protects it from inflammation, oxidation, and other causes of aging. The problem is that the Hemp oil-based products do not penetrate the skin;they remain on the skin’s surface. Recently researchers have been trying to prepare nano emulsions of hemp oil to facilitate its permeation to deep skin layers. In all techniques used today, surfactants are added to the emulsification process. These surfactants may cause unwanted skin side effects. In the present study, we prepare micronized Hemp (m-Hemp) without using any surfactants in the micronization process, thus avoiding the side effects associated with surfactant addition. Methods & Results: Particles size of m-Hemp was evaluated using electron microscopy. Various sizes of m-Hemp were found, the smallest being 100 nm in diameter. The antioxidation properties of m-Hemp were measured using the Electron Spin Resonance (ESR) technique and were found to be enhanced. Skin topography and morphology following a cream containing m-Hemp treatment were visualized by Optical Profilometry and ESEM respectively. The results show a marked improvement in skin topography in all measured parameters. In addition, human keratinocytes (HaCaT) were exposed to inflammatory conditions and were then treated using Hemp. As a result, one of the key inflammatory factors (IL-2) was significantly reduced after treatment with m-Hemp (p ≤ 0.0001). The skin penetration of the cream containing m-Hemp was tested on human skin using the IMOPE (Iterative Multi-plane Optical Property Extraction) system. The results indicate that m-Hemp penetrates both the stratum corneum and the deep epidermal layers towards the dermis. Conclusion: The new cream prepared with micronized Hemp shows significant anti-inflammatory and antioxidative effects and demonstrates the entrance of m-Hemp to the skin epidermal layer.展开更多
Vitamin C (ascorbic acid) plays an important role in maintaining skin health, and topical vitamin C supplementation can counteract oxidative stress induced by UVA, due to excellent reducibility. To clarify the efficac...Vitamin C (ascorbic acid) plays an important role in maintaining skin health, and topical vitamin C supplementation can counteract oxidative stress induced by UVA, due to excellent reducibility. To clarify the efficacy of vitamin C on the skin in the carrier of lotion, we studied its permeability, irritation and anti-aging effect in vitro and in vivo, using Franz cell system, cell model and clinical test. The permeability test showed that vitamin C with 10%, 15%, 20% and 25% mass ratio could effectively penetrate skin. The 20% of vitamin C lotion (VCL-20%) had the highest efficiency of transdermal penetration and the diffusion percentage reached 84.707% after 24 h. Besides, the permeation quantity of VCL-20% was 1.43 times that of the control group. Irritation test showed that the cytotoxicity of vitamin C lotion was low. And no allergic reaction happened in the occlusive patch test. Compared with the control group, using vitamin C lotion for 28 days could significantly improve subjects’ skin gloss of 10.53% and improve skin color, enhance facial skin elasticity and tightness of 9.20% and reduce wrinkle area of 12.27% (p < 0.05).展开更多
Recently, liposomes have been widely used in cancer therapeutics, but their anti-tumor effects are suboptimal due to limited tumor penetration. To solve this problem, researchers have made significant efforts to optim...Recently, liposomes have been widely used in cancer therapeutics, but their anti-tumor effects are suboptimal due to limited tumor penetration. To solve this problem, researchers have made significant efforts to optimize liposomal diameters and potentials, but little attention has been paid to liposomal membrane rigidity. Herein, we sought to demonstrate the effects of cholesterol-tuned liposomal membrane rigidity on tumor penetration and anti-tumor effects. In this study, liposomes composed of hydrogenated soybean phospholipids(HSPC), 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000](DSPE-PEG2000) and different concentrations of cholesterol were prepared. It was revealed that liposomal membrane rigidity decreased with the addition of cholesterol. Moderate cholesterol content conferred excellent diffusivity to liposomes in simulated diffusion medium, while excessive cholesterol limited the diffusion process. We concluded that the differences of the diffusion rates likely stemmed from the alterations in liposomal membrane rigidity, with moderate rigidity leading to improved diffusion. Next, the in vitro tumor penetration and the in vivo anti-tumor effects were analyzed. The results showed that liposomes with moderate rigidity gained excellent tumor penetration and enhanced anti-tumor effects. These findings illustrate a feasible and effective way to improve tumor penetration and therapeutic efficacy of liposomes by changing the cholesterol content, and highlight the importance of liposomal membrane rigidity.展开更多
基金Project(60925011) supported by the National Natural Science Foundation for Distinguished Young Scholars of ChinaProject(9140A06040510BQXXXX) supported by Advanced Research Foundation of General Armament Department,China
文摘To address the issue of premature convergence and slow convergence rate in three-dimensional (3D) route planning of unmanned aerial vehicle (UAV) low-altitude penetration,a novel route planning method was proposed.First and foremost,a coevolutionary multi-agent genetic algorithm (CE-MAGA) was formed by introducing coevolutionary mechanism to multi-agent genetic algorithm (MAGA),an efficient global optimization algorithm.A dynamic route representation form was also adopted to improve the flight route accuracy.Moreover,an efficient constraint handling method was used to simplify the treatment of multi-constraint and reduce the time-cost of planning computation.Simulation and corresponding analysis show that the planning results of CE-MAGA have better performance on terrain following,terrain avoidance,threat avoidance (TF/TA2) and lower route costs than other existing algorithms.In addition,feasible flight routes can be acquired within 2 s,and the convergence rate of the whole evolutionary process is very fast.
基金financially supported by the Fundamental Research Funds for the Central Universities of China (FRF-GF-17-B21)
文摘A high-entropy alloy–ceramic gradient composite of TiC–TiB_2/75vol% Al_(0.3) CoCrFe Ni was successfully prepared by combustion synthesis under an ultra-high gravity field, which is a low-cost method with high efficiency. The ceramic particles were gradient distributed in the Al_(0.3) CoCrFe Ni matrix, and the hardness of the composite material gradually decreased along the thickness direction. The anti-penetration performance of the gradient composites was simulated using the ANSYS/LS-DYNA explicit simulation program. The results demonstrate that the distribution of the ceramic particles strongly affected the mechanical properties and the anti-penetration performance of the composites. With the same total ceramic volume fraction, the gradient composites exhibit better anti-penetration performance than the corresponding ceramic–metal interlayer composites. The more uneven the ceramic distribution, the greater the elastic modulus and yield stress of the surface layer and, thus, the better the anti-penetration performance.
文摘This paper compares the penetration capabilities of the same type anti-ship missiles with millimeter wave(MMW)seeker and centimeter wave seeker,and constructs mathematical models of penetration probability and saturation attack number for all anti-ship missiles used in the countermeasure system,according to the rule which makes the ship-borne air defence system oppase as far as possible and equally,and combining the actual combat situation.It can be seen,from analysis of the countermeasure process between anti-ship missile and surface naval ship,that for the same type of anti-ship missile with different seekers,the main influence on the penetration capability is from electronic jamming system.Based on the built model,the penetration capabilities of the same type anti-ship missiles with MMW and centimeter wave seekers are simulated.The simulated results show that the penetration capability of MMW seeker is slightly better than that of the centimeter wave seeker and its saturation attack number is also influenced by the discovering probability greatly.Finally,some suggestions to get superior penetration effect are given for a commander to choose seeker type suitably.
文摘We study the two-dimensional above-barrier penetration and the sub-barrier tunneling of non-relativistic particles and photons, described in the quasi-monochromatic approximation by simple plane waves. Our scheme represents the motion from the left free-motion zero-potential region to the right zero-potential region through the intermediate region with a one-dimensional rectangular potential barrier along the axis, normal to the both parallel interfaces between all three regions, and with the zero potential along the axis, parallel to the those interfaces. We have firstly obtained the analytical expressions for the infinite series of multiple internal and external reflections and also of multiple transmitted waves of particles and photons, with equal shifts between them along the interfaces for the above-barrier penetration and with various shifts between them in the case of the sub-barrier tunneling. Finally the Hartman and Fletcher effect for any transmitted wave is established.
文摘Based on the analysis for the interception process of ship-to-air missile system to the anti-ship missile stream, the antagonism of ship-to-air missile and anti-ship missile stream was modeled by Monte Carlo method. This model containing the probability of acquiring anti-ship missile, threat estimation, firepower distribution, interception, effectiveness evaluation and firepower turning, can dynamically simulate the antagonism process of anti-ship missile attack stream and anti-air missile weapon system. The anti-ship missile's saturation attack stream for different ship-to-air missile systems can be calculated quantitatively. The simulated results reveal the relations among the anti-ship missile saturation attack and the attack intensity of anti-ship missile, interception mode and the main parameters of anti-air missile weapon system. It provides a theoretical basis for the effective operation of anti-ship missile.
文摘Objective: Hemp seed oil is perfect for most skin types;it moisturizes skin and protects it from inflammation, oxidation, and other causes of aging. The problem is that the Hemp oil-based products do not penetrate the skin;they remain on the skin’s surface. Recently researchers have been trying to prepare nano emulsions of hemp oil to facilitate its permeation to deep skin layers. In all techniques used today, surfactants are added to the emulsification process. These surfactants may cause unwanted skin side effects. In the present study, we prepare micronized Hemp (m-Hemp) without using any surfactants in the micronization process, thus avoiding the side effects associated with surfactant addition. Methods & Results: Particles size of m-Hemp was evaluated using electron microscopy. Various sizes of m-Hemp were found, the smallest being 100 nm in diameter. The antioxidation properties of m-Hemp were measured using the Electron Spin Resonance (ESR) technique and were found to be enhanced. Skin topography and morphology following a cream containing m-Hemp treatment were visualized by Optical Profilometry and ESEM respectively. The results show a marked improvement in skin topography in all measured parameters. In addition, human keratinocytes (HaCaT) were exposed to inflammatory conditions and were then treated using Hemp. As a result, one of the key inflammatory factors (IL-2) was significantly reduced after treatment with m-Hemp (p ≤ 0.0001). The skin penetration of the cream containing m-Hemp was tested on human skin using the IMOPE (Iterative Multi-plane Optical Property Extraction) system. The results indicate that m-Hemp penetrates both the stratum corneum and the deep epidermal layers towards the dermis. Conclusion: The new cream prepared with micronized Hemp shows significant anti-inflammatory and antioxidative effects and demonstrates the entrance of m-Hemp to the skin epidermal layer.
文摘Vitamin C (ascorbic acid) plays an important role in maintaining skin health, and topical vitamin C supplementation can counteract oxidative stress induced by UVA, due to excellent reducibility. To clarify the efficacy of vitamin C on the skin in the carrier of lotion, we studied its permeability, irritation and anti-aging effect in vitro and in vivo, using Franz cell system, cell model and clinical test. The permeability test showed that vitamin C with 10%, 15%, 20% and 25% mass ratio could effectively penetrate skin. The 20% of vitamin C lotion (VCL-20%) had the highest efficiency of transdermal penetration and the diffusion percentage reached 84.707% after 24 h. Besides, the permeation quantity of VCL-20% was 1.43 times that of the control group. Irritation test showed that the cytotoxicity of vitamin C lotion was low. And no allergic reaction happened in the occlusive patch test. Compared with the control group, using vitamin C lotion for 28 days could significantly improve subjects’ skin gloss of 10.53% and improve skin color, enhance facial skin elasticity and tightness of 9.20% and reduce wrinkle area of 12.27% (p < 0.05).
基金supported by the National Natural Science Foundation of China(81573378 and 81773651)the Science and Technology Innovation Action Plan for Basic Research of Shanghai 2014(14JC1493200,China)+1 种基金Shanghai Sailing Program2017(17YF1423500,China)K.C.Wong Education Foundation(China)
文摘Recently, liposomes have been widely used in cancer therapeutics, but their anti-tumor effects are suboptimal due to limited tumor penetration. To solve this problem, researchers have made significant efforts to optimize liposomal diameters and potentials, but little attention has been paid to liposomal membrane rigidity. Herein, we sought to demonstrate the effects of cholesterol-tuned liposomal membrane rigidity on tumor penetration and anti-tumor effects. In this study, liposomes composed of hydrogenated soybean phospholipids(HSPC), 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000](DSPE-PEG2000) and different concentrations of cholesterol were prepared. It was revealed that liposomal membrane rigidity decreased with the addition of cholesterol. Moderate cholesterol content conferred excellent diffusivity to liposomes in simulated diffusion medium, while excessive cholesterol limited the diffusion process. We concluded that the differences of the diffusion rates likely stemmed from the alterations in liposomal membrane rigidity, with moderate rigidity leading to improved diffusion. Next, the in vitro tumor penetration and the in vivo anti-tumor effects were analyzed. The results showed that liposomes with moderate rigidity gained excellent tumor penetration and enhanced anti-tumor effects. These findings illustrate a feasible and effective way to improve tumor penetration and therapeutic efficacy of liposomes by changing the cholesterol content, and highlight the importance of liposomal membrane rigidity.
