In the original publication the third author name is published incorrectly as“Hayatdavoodi Masoud”.The correct author name should be read as“Masoud Hayatdavoodi”.The correct author name is available in this correc...In the original publication the third author name is published incorrectly as“Hayatdavoodi Masoud”.The correct author name should be read as“Masoud Hayatdavoodi”.The correct author name is available in this correction.展开更多
Periodic metal nanoarrays serving as cavities can support directional-tunable amplified spontaneous emission that goes beyond the diffraction limit due to the hybrid states of surface plasmons and Bloch surface waves....Periodic metal nanoarrays serving as cavities can support directional-tunable amplified spontaneous emission that goes beyond the diffraction limit due to the hybrid states of surface plasmons and Bloch surface waves.Most of these modes'interactions remain within the weak coupling regime,yet strong coupling is also anticipated to occur.In this work,we present an intriguing case of amplified spontaneous emission(ASE),amplified by the splitting upper polariton mode within a strong coupling system,stemming from a square lattice of plasmonic cone lattices(PCLs).The PCLs are fabricated using an anodized aluminum oxide membrane(AAO),which facilitates strong coupling between surface plasmons and Bloch surface wave modes,with the maximum Rabi splitting observed at 0.258 eV for the sample with an aspect ratio of 0.33.A 13.5-fold increase in amplified spontaneous emission is recorded when the emission from Nile Red coincides with this flat energy branch of upper polariton,which exhibits a high photon density of states.Reduced group velocity can prolong photon lifetime and boost the probability of light-matter interaction.The observed ASE phenomenon in this strong coupling plasmonic system widens the scope for applications in nanolasing and polariton lasing.展开更多
At present,the measurement of the near wave field of ships mostly relies on shipborne radar.The commonly used shipborne radar is incoherent and cannot obtain information on wave surface velocity.Therefore,the mathemat...At present,the measurement of the near wave field of ships mostly relies on shipborne radar.The commonly used shipborne radar is incoherent and cannot obtain information on wave surface velocity.Therefore,the mathematical model of wave reconstruction is remarkably complex.As a new type of radar,coherent radar can obtain the radial velocity of the wave surface.Most wave surface reconstruction methods that use wave velocity are currently based on velocity potential.The difficulty of these methods lies in determining the initial value of the velocity integral.This paper proposes a wave surface reconstruction method based on an artificial boundary matrix.Numerical simulation data of regular and short-crest waves are used to verify the accuracy of this method.Simultaneously,the reconstruction stability under different wave velocity measurement errors is analyzed.The calculation results show that the proposed method can effectively realize the reconstruction of wave field.展开更多
Marine biofouling seriously affects human marine exploitation and transportation activities,to which marine antifouling(AF)coatings are considered to be the most cost-effective solution.Since the mid-20th century,huma...Marine biofouling seriously affects human marine exploitation and transportation activities,to which marine antifouling(AF)coatings are considered to be the most cost-effective solution.Since the mid-20th century,human beings have dedicated their efforts on developing AF coatings with long cycle and high performance,leading to a large number of non-target organisms?distortion,death and marine environmental pollution.Polydimethylsiloxane(PDMS),is considered as one of the representative environment-friendly AF materials thanks to its non-toxic,hydrophobic,low surface energy and AF properties.However,PDMS AF coatings are prone to mechanical damage,weak adhesion strength to substrate,and poor static AF effect,which seriously restrict their use in the ocean.The rapid development of various nanomaterials provides an opportunity to enhance and improve the mechanical properties and antifouling properties of PDMS coating by embedding nanomaterials.Based on our research background and the problems faced in our laboratory,this article presents an overview of the current progress in the fields of PDMS composite coatings enhanced by different nanomaterials,with the discussion focused on the advantages and main bottlenecks currently encountered in this field.Finally,we propose an outlook,hoping to provide fundamental guidance for the development of marine AF field.展开更多
The estimation of sparse underwater acoustic(UWA)channels can be regarded as an inference problem involving hidden variables within the Bayesian framework.While the classical sparse Bayesian learning(SBL),derived thro...The estimation of sparse underwater acoustic(UWA)channels can be regarded as an inference problem involving hidden variables within the Bayesian framework.While the classical sparse Bayesian learning(SBL),derived through the expectation maximization(EM)algorithm,has been widely employed for UWA channel estimation,it still differs from the real posterior expectation of channels.In this paper,we propose an approach that combines variational inference(VI)and Markov chain Monte Carlo(MCMC)methods to provide a more accurate posterior estimation.Specifically,the SBL is first re-derived with VI,allowing us to replace the posterior distribution of the hidden variables with a variational distribution.Then,we determine the full conditional probability distribution for each variable in the variational distribution and then iteratively perform random Gibbs sampling in MCMC to converge the Markov chain.The results of simulation and experiment indicate that our estimation method achieves lower mean square error and bit error rate compared to the classic SBL approach.Additionally,it demonstrates an acceptable convergence speed.展开更多
At present,studies on large-amplitude internal solitary waves mostly adopt strong stratification models,such as the twoand three-layer Miyata–Choi–Camassa(MCC)internal wave models,which omit the pycnocline or treat ...At present,studies on large-amplitude internal solitary waves mostly adopt strong stratification models,such as the twoand three-layer Miyata–Choi–Camassa(MCC)internal wave models,which omit the pycnocline or treat it as another fluid layer with a constant density.Because the pycnocline exists in real oceans and cannot be omitted sometimes,the computational error of a large-amplitude internal solitary wave within the pycnocline introduced by the strong stratification approximation is unclear.In this study,the two-and three-layer MCC internal wave models are used to calculate the wave profile and wave speed of large-amplitude internal solitary waves.By comparing these results with the results provided by the Dubreil–Jacotin–Long(DJL)equation,which accurately describes large-amplitude internal solitary waves in a continuous density stratification,the computational errors of large-amplitude internal solitary waves at different pycnocline depths introduced by the strong stratification approximation are assessed.Although the pycnocline thicknesses are relatively large(accounting for 8%–10%of the total water depth),the error is much smaller under the three-layer approximation than under the two-layer approximation.展开更多
文摘In the original publication the third author name is published incorrectly as“Hayatdavoodi Masoud”.The correct author name should be read as“Masoud Hayatdavoodi”.The correct author name is available in this correction.
基金financial supports from National Natural Science Foundation of China(No.61905051)Natural Science Foundation of Heilongjiang Province(No.LH2020F027).
文摘Periodic metal nanoarrays serving as cavities can support directional-tunable amplified spontaneous emission that goes beyond the diffraction limit due to the hybrid states of surface plasmons and Bloch surface waves.Most of these modes'interactions remain within the weak coupling regime,yet strong coupling is also anticipated to occur.In this work,we present an intriguing case of amplified spontaneous emission(ASE),amplified by the splitting upper polariton mode within a strong coupling system,stemming from a square lattice of plasmonic cone lattices(PCLs).The PCLs are fabricated using an anodized aluminum oxide membrane(AAO),which facilitates strong coupling between surface plasmons and Bloch surface wave modes,with the maximum Rabi splitting observed at 0.258 eV for the sample with an aspect ratio of 0.33.A 13.5-fold increase in amplified spontaneous emission is recorded when the emission from Nile Red coincides with this flat energy branch of upper polariton,which exhibits a high photon density of states.Reduced group velocity can prolong photon lifetime and boost the probability of light-matter interaction.The observed ASE phenomenon in this strong coupling plasmonic system widens the scope for applications in nanolasing and polariton lasing.
基金Supported by the National Natural Science Foundation of China under Grant No.51809066.
文摘At present,the measurement of the near wave field of ships mostly relies on shipborne radar.The commonly used shipborne radar is incoherent and cannot obtain information on wave surface velocity.Therefore,the mathematical model of wave reconstruction is remarkably complex.As a new type of radar,coherent radar can obtain the radial velocity of the wave surface.Most wave surface reconstruction methods that use wave velocity are currently based on velocity potential.The difficulty of these methods lies in determining the initial value of the velocity integral.This paper proposes a wave surface reconstruction method based on an artificial boundary matrix.Numerical simulation data of regular and short-crest waves are used to verify the accuracy of this method.Simultaneously,the reconstruction stability under different wave velocity measurement errors is analyzed.The calculation results show that the proposed method can effectively realize the reconstruction of wave field.
基金financially supported by National Natural Science Foundation of China(Grant No.52073071,51803041)Natural Science Funding for Excellent Young Scholar of Heilongjiang Province(YQ2022E021,L.Wang)+2 种基金the Fundamental Research Funds for the Central Universities(HIT.DZJJ.2023056)the Research Fund of State Key Laboratory for Marine Corrosion and Protection of Luoyang Ship Material Research Institute(No.JS220407)the financial support from the Spanish Ministry of Economy and the Canary Islands program Vieray Clavijo Senior(Ref.2023/00001156)。
文摘Marine biofouling seriously affects human marine exploitation and transportation activities,to which marine antifouling(AF)coatings are considered to be the most cost-effective solution.Since the mid-20th century,human beings have dedicated their efforts on developing AF coatings with long cycle and high performance,leading to a large number of non-target organisms?distortion,death and marine environmental pollution.Polydimethylsiloxane(PDMS),is considered as one of the representative environment-friendly AF materials thanks to its non-toxic,hydrophobic,low surface energy and AF properties.However,PDMS AF coatings are prone to mechanical damage,weak adhesion strength to substrate,and poor static AF effect,which seriously restrict their use in the ocean.The rapid development of various nanomaterials provides an opportunity to enhance and improve the mechanical properties and antifouling properties of PDMS coating by embedding nanomaterials.Based on our research background and the problems faced in our laboratory,this article presents an overview of the current progress in the fields of PDMS composite coatings enhanced by different nanomaterials,with the discussion focused on the advantages and main bottlenecks currently encountered in this field.Finally,we propose an outlook,hoping to provide fundamental guidance for the development of marine AF field.
基金funded by the Excellent Youth Science Fund of Heilongjiang Province(Grant No.YQ2022F001).
文摘The estimation of sparse underwater acoustic(UWA)channels can be regarded as an inference problem involving hidden variables within the Bayesian framework.While the classical sparse Bayesian learning(SBL),derived through the expectation maximization(EM)algorithm,has been widely employed for UWA channel estimation,it still differs from the real posterior expectation of channels.In this paper,we propose an approach that combines variational inference(VI)and Markov chain Monte Carlo(MCMC)methods to provide a more accurate posterior estimation.Specifically,the SBL is first re-derived with VI,allowing us to replace the posterior distribution of the hidden variables with a variational distribution.Then,we determine the full conditional probability distribution for each variable in the variational distribution and then iteratively perform random Gibbs sampling in MCMC to converge the Markov chain.The results of simulation and experiment indicate that our estimation method achieves lower mean square error and bit error rate compared to the classic SBL approach.Additionally,it demonstrates an acceptable convergence speed.
基金the Fundamental Research Funds for the Central Universities (No. 3072022FSC0101)the National Natural Science Foundation of China (Nos. 12202114, 52261135547)+4 种基金the China Postdoctoral Science Foundation (No. 2022M710932)the State Key Laboratory of Coastal and Offshore EngineeringDalian University of Technology (No. LP2202)the Qingdao Postdoctoral Application Projectthe Heilongjiang Touyan Innovation Team Program
文摘At present,studies on large-amplitude internal solitary waves mostly adopt strong stratification models,such as the twoand three-layer Miyata–Choi–Camassa(MCC)internal wave models,which omit the pycnocline or treat it as another fluid layer with a constant density.Because the pycnocline exists in real oceans and cannot be omitted sometimes,the computational error of a large-amplitude internal solitary wave within the pycnocline introduced by the strong stratification approximation is unclear.In this study,the two-and three-layer MCC internal wave models are used to calculate the wave profile and wave speed of large-amplitude internal solitary waves.By comparing these results with the results provided by the Dubreil–Jacotin–Long(DJL)equation,which accurately describes large-amplitude internal solitary waves in a continuous density stratification,the computational errors of large-amplitude internal solitary waves at different pycnocline depths introduced by the strong stratification approximation are assessed.Although the pycnocline thicknesses are relatively large(accounting for 8%–10%of the total water depth),the error is much smaller under the three-layer approximation than under the two-layer approximation.