This paper presents 2.5D scattering of incident plane SH waves by a canyon in layered half-space by the indirect boundary element method (IBEM). The free field response is carried out to give the displacements and str...This paper presents 2.5D scattering of incident plane SH waves by a canyon in layered half-space by the indirect boundary element method (IBEM). The free field response is carried out to give the displacements and stresses on the line which forms boundary of the canyon. The fictitious uniform moving loads are applied to the same line to calculate the Green's functions for the displacements and stresses. The amplitudes of the loads are determined by the boundary conditions. The displacements due to the free field and from the fictitious uniform moving loads have to be added to obtain the whole motion. The numerical results are carried out for the cases of a canyon in homogenous and in one layer over bedrock. The results show that the 2.5D wave scattering problem is essentially different from the 2D case, and there exist distinct differences between the wave amplification by a canyon in layered half-space and that in homogeneous half-space. The reasons for the distinct difference are explored, and the effects of the thickness and stiffness of the layer on the amplification are discussed.展开更多
随着摩尔定律指引下的晶体管微缩逼近物理极限,先进封装技术通过系统微型化与异构集成,成为突破芯片性能瓶颈的关键路径。作为先进封装的核心分支,2.5D封装通过硅/玻璃中介层实现高密度互连与多芯片异构集成,兼具高带宽、低延迟和小型...随着摩尔定律指引下的晶体管微缩逼近物理极限,先进封装技术通过系统微型化与异构集成,成为突破芯片性能瓶颈的关键路径。作为先进封装的核心分支,2.5D封装通过硅/玻璃中介层实现高密度互连与多芯片异构集成,兼具高带宽、低延迟和小型化优势,广泛应用于人工智能、高性能计算及移动电子领域。系统阐述了2.5D封装的核心结构(如Co Wo S、EMIB和I-Cube)及其技术特征,重点剖析了Chiplet模块化设计、硅通孔(TSV)工艺优化、微凸点可靠性提升、铜-铜直接键合界面工程以及再布线层多物理场协同设计等关键技术的最新进展。未来研究需聚焦低成本玻璃基板、原子层沉积技术抑制界面氧化以及多物理场协同设计等方面,以突破良率和散热瓶颈,推动2.5D封装在后摩尔时代高算力场景中的广泛应用。展开更多
Transforming a scattering medium into a lens for imaging very simple binary objects is possible;however,it remains challenging to image complex grayscale objects,let alone measure 3D continuous distribution objects.He...Transforming a scattering medium into a lens for imaging very simple binary objects is possible;however,it remains challenging to image complex grayscale objects,let alone measure 3D continuous distribution objects.Here,we propose and demonstrate the use of a ground glass diffuser as a scattering lens for imaging complex grayscale fringes,and we employ it to achieve microscopic structured light 3D imaging(MSL3DI).The ubiquitous property of the speckle patterns permits the exploitation of the scattering medium as an ultra-thin scattering lens with a variable focal length and a flexible working distance for microscale object measurement.The method provides a light,flexible,and cost-effective imaging device as an alternative to microscope objectives or telecentric lenses in conventional MSL3DI systems.We experimentally demonstrate that employing a scattering lens allows us to achieve relatively good phase information and robust 3D imaging from depth measurements,yielding measurement accuracy only marginally lower than that of a telecentric lens,typically within approximately 10μm.Furthermore,the scattering lens demonstrates robust performance even when the imaging distance exceeds the typical working distance of a telecentric lens.The proposed method facilitates the application of scattering imaging techniques,providing a more flexible solution for MSL3DI.展开更多
Obtaining the ground truth for imaging through the scattering objects is always a challenging task.Furthermore,the scattering process caused by complex media is too intricate to be accurately modeled by either traditi...Obtaining the ground truth for imaging through the scattering objects is always a challenging task.Furthermore,the scattering process caused by complex media is too intricate to be accurately modeled by either traditional physical models or neural networks.To address this issue,we present a learning from better simulation(LBS)method.Utilizing the physical information from a single experimentally captured image through an optimization-based approach,the LBS method bypasses the multiple-scattering process and directly creates highly realistic synthetic data.The data can then be used to train downstream models.As a proof of concept,we train a simple U-Net solely on the synthetic data and demonstrate that it generalizes well to experimental data without requiring any manual labeling.3D holographic particle field monitoring is chosen as the testing bed,and simulation and experimental results are presented to demonstrate the effectiveness and robustness of the proposed technique for imaging of complex scattering media.The proposed method lays the groundwork for reliable particle field imaging in high concentration.The concept of utilizing realistic synthetic data for training can be significantly beneficial in various deep learningbased imaging tasks,especially those involving complex scattering media.展开更多
The application of a controllable neutron source for measuring formation porosity in the advancement of nuclear logging has garnered increased attention.The existing porosity algorithm,which is based on the thermal ne...The application of a controllable neutron source for measuring formation porosity in the advancement of nuclear logging has garnered increased attention.The existing porosity algorithm,which is based on the thermal neutron counting ratio,exhibits lower sensitivity in high-porosity regions.To enhance the sensitivity,the effects of elastic and inelastic scattering,which influence the slowing-down of fast neutrons,were theoretically analyzed,and a slowing-down model of fast neutrons was created.Based on this model,a density correction porosity algorithm was proposed based on the relationship between density,thermal neutron counting ratio,and porosity.Finally,the super multifunctional calculation program for nuclear design and safety evaluation(TopMC/SuperMC)was used to create a simulation model for porosity logging,and its applicability was examined.The results demonstrated that the relative error between the calculated and actual porosities was less than 1%,and the influence of deviation in the density measurement was less than 2%.Therefore,the proposed density correction algorithm based on the slowing-down model of fast neutrons can effectively improve the sensitivity in the high-porosity region.This study is expected to serve as a reference for the application of neutron porosity measurements with D–T neutron sources.展开更多
基金supported by National Natural Science Foundation of China (Nos. 50908156 and 50978183)
文摘This paper presents 2.5D scattering of incident plane SH waves by a canyon in layered half-space by the indirect boundary element method (IBEM). The free field response is carried out to give the displacements and stresses on the line which forms boundary of the canyon. The fictitious uniform moving loads are applied to the same line to calculate the Green's functions for the displacements and stresses. The amplitudes of the loads are determined by the boundary conditions. The displacements due to the free field and from the fictitious uniform moving loads have to be added to obtain the whole motion. The numerical results are carried out for the cases of a canyon in homogenous and in one layer over bedrock. The results show that the 2.5D wave scattering problem is essentially different from the 2D case, and there exist distinct differences between the wave amplification by a canyon in layered half-space and that in homogeneous half-space. The reasons for the distinct difference are explored, and the effects of the thickness and stiffness of the layer on the amplification are discussed.
文摘随着摩尔定律指引下的晶体管微缩逼近物理极限,先进封装技术通过系统微型化与异构集成,成为突破芯片性能瓶颈的关键路径。作为先进封装的核心分支,2.5D封装通过硅/玻璃中介层实现高密度互连与多芯片异构集成,兼具高带宽、低延迟和小型化优势,广泛应用于人工智能、高性能计算及移动电子领域。系统阐述了2.5D封装的核心结构(如Co Wo S、EMIB和I-Cube)及其技术特征,重点剖析了Chiplet模块化设计、硅通孔(TSV)工艺优化、微凸点可靠性提升、铜-铜直接键合界面工程以及再布线层多物理场协同设计等关键技术的最新进展。未来研究需聚焦低成本玻璃基板、原子层沉积技术抑制界面氧化以及多物理场协同设计等方面,以突破良率和散热瓶颈,推动2.5D封装在后摩尔时代高算力场景中的广泛应用。
基金supported by the National Natural Science Foundation of China(Grant Nos.62275188 and 62505216)the Central Guidance on Local Science and Technology Development Fund(Grant No.YDZJSX2024D019)+1 种基金the International Scientific and Technological Cooperative Project in Shanxi Province(Grant No.202104041101009)the Natural Science Foundation of Shanxi Province of China through Research Project(Grant No.20210302123195).
文摘Transforming a scattering medium into a lens for imaging very simple binary objects is possible;however,it remains challenging to image complex grayscale objects,let alone measure 3D continuous distribution objects.Here,we propose and demonstrate the use of a ground glass diffuser as a scattering lens for imaging complex grayscale fringes,and we employ it to achieve microscopic structured light 3D imaging(MSL3DI).The ubiquitous property of the speckle patterns permits the exploitation of the scattering medium as an ultra-thin scattering lens with a variable focal length and a flexible working distance for microscale object measurement.The method provides a light,flexible,and cost-effective imaging device as an alternative to microscope objectives or telecentric lenses in conventional MSL3DI systems.We experimentally demonstrate that employing a scattering lens allows us to achieve relatively good phase information and robust 3D imaging from depth measurements,yielding measurement accuracy only marginally lower than that of a telecentric lens,typically within approximately 10μm.Furthermore,the scattering lens demonstrates robust performance even when the imaging distance exceeds the typical working distance of a telecentric lens.The proposed method facilitates the application of scattering imaging techniques,providing a more flexible solution for MSL3DI.
基金supported by the National Key Research and Development Program of China(Grant Nos.2022YFB2804300 and 2023YFB3611500)the National Natural Science Foundation of China(Grant No.62275218)+1 种基金the China Postdoctoral Science Foundation(Grant No.2022M712586)the Guangdong Basic and Applied Basic Research Foundation(Grant No.2023A1515011335).
文摘Obtaining the ground truth for imaging through the scattering objects is always a challenging task.Furthermore,the scattering process caused by complex media is too intricate to be accurately modeled by either traditional physical models or neural networks.To address this issue,we present a learning from better simulation(LBS)method.Utilizing the physical information from a single experimentally captured image through an optimization-based approach,the LBS method bypasses the multiple-scattering process and directly creates highly realistic synthetic data.The data can then be used to train downstream models.As a proof of concept,we train a simple U-Net solely on the synthetic data and demonstrate that it generalizes well to experimental data without requiring any manual labeling.3D holographic particle field monitoring is chosen as the testing bed,and simulation and experimental results are presented to demonstrate the effectiveness and robustness of the proposed technique for imaging of complex scattering media.The proposed method lays the groundwork for reliable particle field imaging in high concentration.The concept of utilizing realistic synthetic data for training can be significantly beneficial in various deep learningbased imaging tasks,especially those involving complex scattering media.
基金supported by the Anhui Provincial Major Science and Technology Project(No.201903c08020003)the Taishan industrial Experts Program。
文摘The application of a controllable neutron source for measuring formation porosity in the advancement of nuclear logging has garnered increased attention.The existing porosity algorithm,which is based on the thermal neutron counting ratio,exhibits lower sensitivity in high-porosity regions.To enhance the sensitivity,the effects of elastic and inelastic scattering,which influence the slowing-down of fast neutrons,were theoretically analyzed,and a slowing-down model of fast neutrons was created.Based on this model,a density correction porosity algorithm was proposed based on the relationship between density,thermal neutron counting ratio,and porosity.Finally,the super multifunctional calculation program for nuclear design and safety evaluation(TopMC/SuperMC)was used to create a simulation model for porosity logging,and its applicability was examined.The results demonstrated that the relative error between the calculated and actual porosities was less than 1%,and the influence of deviation in the density measurement was less than 2%.Therefore,the proposed density correction algorithm based on the slowing-down model of fast neutrons can effectively improve the sensitivity in the high-porosity region.This study is expected to serve as a reference for the application of neutron porosity measurements with D–T neutron sources.