An adaptive decentralized asymptotic tracking control scheme is developed in this paper for a class of large-scale nonlinear systems with unknown strong interconnections,unknown time-varying parameters,and disturbance...An adaptive decentralized asymptotic tracking control scheme is developed in this paper for a class of large-scale nonlinear systems with unknown strong interconnections,unknown time-varying parameters,and disturbances.First,by employing the intrinsic properties of Gaussian functions for the interconnection terms for the first time,all extra signals in the framework of decentralized control are filtered out,thereby removing all additional assumptions imposed on the interconnec-tions,such as upper bounding functions and matching conditions.Second,by introducing two integral bounded functions,asymptotic tracking control is realized.Moreover,the nonlinear filters with the compensation terms are introduced to circumvent the issue of“explosion of complexity”.It is shown that all the closed-loop signals are bounded and the tracking errors converge to zero asymptotically.In the end,a simulation example is carried out to demonstrate the effectiveness of the proposed approach.展开更多
The traditional nano-sintering or TLP techniques are generally expensive,time-consuming,and hence unsuitable for realizing practical mass production.Herein,we have developed an improved TLP process to rapidly produce ...The traditional nano-sintering or TLP techniques are generally expensive,time-consuming,and hence unsuitable for realizing practical mass production.Herein,we have developed an improved TLP process to rapidly produce IMC-skeleton structures across the bonding region by initiating a localized liquid-solid interaction among micron particles at traditional soldering temperatures.The developed IMC skeletons can reinforce solder alloys and provide remarkable mechanical stability and electrical capabilities at high temperatures.As a result,the IMC-skeleton strengthened interconnections exhibited higher thermal/electrical conductivity,lower hardness and almost doubled strength than traditional full-IMC joints,attaining 87.4 MPa and 30.2 MPa at room condition and 350℃.Meanwhile,the necessary heating time to form metallurgical bonds was shortened,one-fifth of nano-sintering and one-tenth of TLP bonding,and the material cost was significantly reduced.This proposed technique enabled the fast,low-cost manufacturing of electronics that can serve at temperatures as high as 200−350℃.Besides,the interfacial reactions among particles and the correlated phase evolution process were studied in this research.The formation mechanism of IMC skeletons was analyzed.The correlated influencing factors and their effect on the mechanical,thermal and electrical properties of joints were revealed,which may help the design and extensive uses of such techniques in various high-temperature/power applications.展开更多
Interconnections in microelectronic packaging are not only the physical carrier to realize the function of electronic circuits,but also the weak spots in reliability tests.Most of failures in power devices are caused ...Interconnections in microelectronic packaging are not only the physical carrier to realize the function of electronic circuits,but also the weak spots in reliability tests.Most of failures in power devices are caused by the malfunction of interconnections,including failure of bonding wire as well as cracks of solder layer.In fact,the interconnection failure of power devices is the result of a combination of factors such as electricity,temperature,and force.It is significant to investigate the failure mechanisms of various factors for the failure analysis of interconnections in power devices.This paper reviews the main failure modes of bonding wire and solder layer in the interconnection structure of power devices,and its failure mechanism.Then the reliability test method and failure analysis techniques of interconnection in power device are introduced.These methods are of great significance to the reliability analysis and life prediction of power devices.展开更多
The global water demand and supply situation is becoming increasingly severe due to water shortage and uneven distribution of water resources.The highest water demand in the energy sector is attributable to power gene...The global water demand and supply situation is becoming increasingly severe due to water shortage and uneven distribution of water resources.The highest water demand in the energy sector is attributable to power generation.With cross-country and cross-continental power grid interconnections becoming a reality,electricity trading across countries and the creation of new opportunities for re-allocation of water resources are possible.This study expands the concept of virtual water and proposes a generalized virtual water flow in an interconnected power grid system to accurately estimate water resource benefits of clean power transmission from both the production and the consumption sides.By defining the water scarcity index as a price mechanism indicator,the benefits of water resources allocation through power grid interconnections are evaluated.Taking the Africa-Asia-Europe interconnection scenario as an example,the total water saving would amount to 88.95 million m^3 by 2030 and 337.8 million m^3 by 2050.This result shows that grid interconnections could promote the development of renewable energy and expand the benefits of available water resources.展开更多
This study presents a comprehensive impact analysis of the rotor angle stability of a proposed international connection between the Philippines and Sabah,Malaysia,as part of the Association of Southeast Asian Nations(...This study presents a comprehensive impact analysis of the rotor angle stability of a proposed international connection between the Philippines and Sabah,Malaysia,as part of the Association of Southeast Asian Nations(ASEAN)Power Grid.This study focuses on modeling and evaluating the dynamic performance of the interconnected system,considering the high penetration of renewable sources.Power flow,small signal stability,and transient stability analyses were conducted to assess the ability of the proposed linked power system models to withstand small and large disturbances,utilizing the Power Systems Analysis Toolbox(PSAT)software in MATLAB.All components used in the model are documented in the PSAT library.Currently,there is a lack of publicly available studies regarding the implementation of this specific system.Additionally,the study investigates the behavior of a system with a high penetration of renewable energy sources.Based on the findings,this study concludes that a system is generally stable when interconnection is realized,given its appropriate location and dynamic component parameters.Furthermore,the critical eigenvalues of the system also exhibited improvement as the renewable energy sources were augmented.展开更多
We propose a cost-effective scheme relying exclusively on pilot symbols for robust frame synchronization and high-precision,wide-range carrier recovery in short-reach optical interconnects.Our method mitigates phase o...We propose a cost-effective scheme relying exclusively on pilot symbols for robust frame synchronization and high-precision,wide-range carrier recovery in short-reach optical interconnects.Our method mitigates phase offsets and enhances phase tracking by strategically placing dual-polarization pilot symbols,both aligned and misaligned,within the frame.Compared to traditional carrier recovery schemes,our approach offers a broader frequency offset estimation range,higher carrier recovery accuracy,and significantly lower computational complexity.Experimental results show a 0.7 dB sensitivity improvement at the soft decision forward error correction threshold,outperforming Fourier transform-based frequency offset estimation combined with blind phase search.展开更多
Nano-twinned copper(nt-Cu),with a preferred orientation,is highly promising as interconnect materials in high-density advanced packaging due to its considerable mechanical strength,excellent electrical conductivity,an...Nano-twinned copper(nt-Cu),with a preferred orientation,is highly promising as interconnect materials in high-density advanced packaging due to its considerable mechanical strength,excellent electrical conductivity,and resistance to thermal migration.However,its application is impeded by sulfur-containing byproducts from the electroplating process,exacerbating the formation of Kirkendall voids within solder joints during thermal aging.Herein,through the incorporation of Zinc(Zn)into the nt-Cu layer,we develop a nt-Cu/Zn composite structure.Our findings provide the first definitive confirmation of the mechanism by which sulfur atoms migrate to the Cu_(3)Sn/nt-Cu interface through interstitial diffusion,thereby reducing the activation energy for vacancy formation.We further demonstrate that Zn effectively an-choring sulfur atoms,forming ZnS within the nt-Cu layer during heat treatment,which increases the vacancy formation energy and inhibits the development of Kirkendall voids.Remarkably,no Kirkendall voids are observed in the modified interconnects even after prolonged aging at 150℃ for 1000 h.The nt-Cu/Zn composite metallization layers significantly decrease the growth rate of interfacial intermetallic compounds by 33.6% and enhance the shear strength of solder interconnections to 228.9%.This research underscores the potential of nt-Cu in advanced electronic packaging,offering new pathways for improving the power density and reliability of electronic devices.展开更多
This paper proposes a novel modified uni-traveling-carrier photodiode(MUTC-PD)featuring an electric field regulation layer:a p-type doped thin layer inserted behind the PD’s n-doped cliff layer.This electric field re...This paper proposes a novel modified uni-traveling-carrier photodiode(MUTC-PD)featuring an electric field regulation layer:a p-type doped thin layer inserted behind the PD’s n-doped cliff layer.This electric field regulation layer enhances the PD’s performance by not only reducing and smoothing the electric field intensity in the collector layer,allowing photo-generated electrons to transit at peak drift velocity,but also improving the electric field intensity in the depleted absorber layer and optimizing the photo-generated carriers’saturated transit performance.Additionally,the transport characteristics of the peak drift velocity of photogenerated electrons in the device’s collection layer can be used to optimize its parasitic characteristics.The electron’s peak drift velocity compensates for the lost transit time.Thus improving the 3 dB bandwidth of the PD’s photo response.Finally obtains a MUTC-PD with a 3 dB bandwidth of 68 GHz at a responsivity of 0.502 A/W,making it suitable for 100 Gbit/s optical receivers.展开更多
As global energy demand increases and environmental standards tighten,the development of efficient,eco-friendly energy conversion and storage technologies becomes crucial.Solid oxide cells(SOCs)show great promise beca...As global energy demand increases and environmental standards tighten,the development of efficient,eco-friendly energy conversion and storage technologies becomes crucial.Solid oxide cells(SOCs)show great promise because of their high energy conversion efficiency and wide range of applications.Highentropy materials(HEMs),a novel class of materials comprising several principal elements,have attracted significant interest within the materials science and energy sectors.Their distinctive structural features and adaptable functional properties offer immense potential for innovation across various applications.This review systematically covers the basic concepts,crystal structures,element selection,and major synthesis strategies of HEMs,and explores in detail the specific applications of these materials in SOCs,including its potential as air electrodes,fuel electrodes,electrolytes,and interconnects(including barrier coatings).By analyzing existing studies,this review reveals the significant advantages of HEMs in enhancing the performance,anti-poisoning,and stability of SOCs;highlights the key areas and challenges for future research;and looks into possible future directions.展开更多
The organization of biological neuronal networks into functional modules has intrigued scientists and inspired engineers to develop artificial systems.These networks are characterized by two key properties.First,they ...The organization of biological neuronal networks into functional modules has intrigued scientists and inspired engineers to develop artificial systems.These networks are characterized by two key properties.First,they exhibit dense interconnectivity(Braitenburg and Schüz,1998;Campagnola et al.,2022).The strength and probability of connectivity depend on cell type,inter-neuronal distance,and species.Still,every cortical neuron receives input from thousands of other neurons while transmitting output to a similar number of neurons.Second,communication between neurons occurs primarily via chemical or electrical synapses.展开更多
Industrial intelligence and secure interconnection serve as the foundational platform and critical information infrastructure for new industrialization,carrying significant strategic importance.They not only function ...Industrial intelligence and secure interconnection serve as the foundational platform and critical information infrastructure for new industrialization,carrying significant strategic importance.They not only function as the core engine driving the transformation and upgrading of the manufacturing sector and ensuring stable socioeconomic operation but are also vital to enhancing national technological competitiveness and safeguarding industrial security.展开更多
A Malawian perspective on China’s influence,innovation and shared growth In today’s interconnected world,diplomacy,trade,and culture are drawing nations once thought distant closer.A case in point is the growing rel...A Malawian perspective on China’s influence,innovation and shared growth In today’s interconnected world,diplomacy,trade,and culture are drawing nations once thought distant closer.A case in point is the growing relationship between Malawi and China-two geographically and historically distinct countries that are finding powerful common ground and shared aspirations.展开更多
With the rapid development of network technologies,a large number of deployed edge devices and information systems generate massive amounts of data which provide good support for the advancement of data-driven intelli...With the rapid development of network technologies,a large number of deployed edge devices and information systems generate massive amounts of data which provide good support for the advancement of data-driven intelligent models.However,these data often contain sensitive information of users.Federated learning(FL),as a privacy preservation machine learning setting,allows users to obtain a well-trained model without sending the privacy-sensitive local data to the central server.Despite the promising prospect of FL,several significant research challenges need to be addressed before widespread deployment,including network resource allocation,model security,model convergence,etc.In this paper,we first provide a brief survey on some of these works that have been done on FL and discuss the motivations of the Communication Networks(CNs)and FL to mutually enable each other.We analyze the support of network technologies for FL,which requires frequent communication and emphasizes security,as well as the studies on the intelligence of many network scenarios and the improvement of network performance and security by the methods based on FL.At last,some challenges and broader perspectives are explored.展开更多
Multiscale shell structure design is a rational and promising way to regulate the performance of hollow spheres in terms of both functionality and structural robustness,but it remains a big challenge to realize micro-...Multiscale shell structure design is a rational and promising way to regulate the performance of hollow spheres in terms of both functionality and structural robustness,but it remains a big challenge to realize micro-nano engineering of the thin shell while maintaining the low density.In this work,the divisional shell design strategy was adopted to obtain the glass-cobalt-cobalt sulfide composite hollow microspheres(CSH),and an unprecedented stepwise high-temperature chemical reaction-induced aggregation and sub-sequent volume expansion strategy was developed to achieve rational regulation of core-shell structured cobalt-cobalt sulfide building units(BU)assembled on hollow glass microspheres.Special attention has been paid to the sulfidation degree-induced volume control with the underlying mechanism of volume expansion during chemical conversion from metallic cobalt to cobalt sulfide.The electromagnetic prop-erty was found to depend largely on the sulfidation degree due to the volume expansion-induced inter-connecting status regulation among the BU.When evaluated as microwave absorbent,an optimized broad bandwidth of 5.12 GHz and a minimum reflection loss(RLmin)of-45.58 dB of our CSH can be achieved at a thin matching thickness of 1.67 mm and a low filling ratio of 20.04 wt%.In addition to functionality,the divisional shell design also brings the CSH high structural strength(92.36%survival rate at a high hydrostatic pressure of 20 MPa)at low density(0.73 g cm^(-3)).展开更多
As the demand for computing power in data centers continues to grow, balancing data transmitting speed and energy efficiency has emerged as a critical challenge. Highbandwidth, low-power interconnection schemes are in...As the demand for computing power in data centers continues to grow, balancing data transmitting speed and energy efficiency has emerged as a critical challenge. Highbandwidth, low-power interconnection schemes are increasingly recognized as core requirements for next-generation intelligent computing center designs^([1, 2]). For short-range optical interconnections of intra-chip and inter-chip—typically covering tens of meters or less—microring resonant modulators (MRM) are emerging as an ideal solution.展开更多
Chongqing,the only municipality directly under the central government in China’s central and western regions,is distinguished by its unique identity as both a“mountain city”and a“river city.”Recognized as the bir...Chongqing,the only municipality directly under the central government in China’s central and western regions,is distinguished by its unique identity as both a“mountain city”and a“river city.”Recognized as the birthplace of Bayu culture,an influential ancient culture native to the Chongqing area,the city boasts a recorded history of more than 3,000 years.As a crucial strategic hub in the development of China’s western regions,Chongqing occupies a pivotal position in the interconnected networks fostered by the Belt and Road Initiative and the Yangtze River Economic Belt.Leveraging the golden waterway of the Yangtze River,the China-Europe Railway Express(Chengdu-Chongqing),and the New International Land-Sea Trade Corridor,Chongqing has emerged as a crucial gateway for China’s opening-up.展开更多
Metal composites produced through the liquid metal dealloying(LMD)process feature an advanced matrix-matrix composite structure,where two metallic materials form a continuous,three-dimensional interconnected network.T...Metal composites produced through the liquid metal dealloying(LMD)process feature an advanced matrix-matrix composite structure,where two metallic materials form a continuous,three-dimensional interconnected network.This study investigates the effects of Ti Cu precursor compositions on dealloying behavior and microstructural evolution in liquid Mg,using Ti_(50)Cu_(50)and Ti_(30)Cu_(70)precursors.The initial microstructure of the precursor significantly influences dealloying kinetics and phase transitions.The single-phase Ti_(50)Cu_(50)precursor exhibits a faster initial dealloying rate due to its homogeneous structure,yet complete dealloying requires 90 min.In contrast,the dualphase Ti_(30)Cu_(70)precursor achieves complete dealloying in 30 min,demonstrating the impact of a higher Cu concentration on accelerating the process kinetics.Additionally,the study explores the coarsening behavior and hardness variations during the LMD process,along with the microstructural characteristics of Mg-Ti composites fabricated from these two precursors.The findings highlight the critical role of precursor composition in tailoring the microstructure and properties of Mg-Ti composites produced through the LMD process,demonstrating its potential for advanced composite material manufacturing.展开更多
High-density interconnect(HDI)soft electronics that can integrate multiple individual functions into one miniaturized monolithic system is promising for applications related to smart healthcare,soft robotics,and human...High-density interconnect(HDI)soft electronics that can integrate multiple individual functions into one miniaturized monolithic system is promising for applications related to smart healthcare,soft robotics,and human-machine interactions.However,despite the recent advances,the development of three-dimensional(3D)soft electronics with both high resolution and high integration is still challenging because of the lack of efficient manufacturing methods to guarantee interlayer alignment of the high-density vias and reliable interlayer electrical conductivity.Here,an advanced 3D laser printing pathway,based on femtosecond laser direct writing(FLDW),is demonstrated for preparing liquid metal(LM)-based any layer HDI soft electronics.FLDW technology,with the characteristics of high spatial resolution and high precision,allows the maskless fabrication of high-resolution embedded LM microchannels and high-density vertical interconnect accesses for 3D integrated circuits.High-aspect-ratio blind/through LM microstructures are formed inside the elastomer due to the supermetalphobicity induced during laser ablation.The LM-based HDI circuit featuring high resolution(~1.5μm)and high integration(10-layer electrical interconnection)is achieved for customized soft electronics,including various customized multilayer passive electric components,soft multilayer circuit,and cross-scale multimode sensors.The 3D laser printing method provides a versatile approach for developing chip-level soft electronics.展开更多
The competence to distinguish points of view is an essential skill in today’s interconnected and information-rich world.Here’s why it is so important:区分观点的能力是当今互联互通、信息丰富的世界中一项必不可少的技能...The competence to distinguish points of view is an essential skill in today’s interconnected and information-rich world.Here’s why it is so important:区分观点的能力是当今互联互通、信息丰富的世界中一项必不可少的技能。以下是它如此重要的原因。展开更多
基金This work was supported in part by the National Natural Science Foundation of China(61873151,62073201)in part by the Shandong Provincial Natural Science Foundation of China(ZR2019MF009)+2 种基金the Taishan Scholar Project of Shandong Province of China(tsqn201909078)the Major Scientific and Technological Innovation Project of Shandong Province,China(2019JAZZ020812)in part by the Major Program of Shandong Province Natural Science Foundation,China(ZR2018ZB0419).
文摘An adaptive decentralized asymptotic tracking control scheme is developed in this paper for a class of large-scale nonlinear systems with unknown strong interconnections,unknown time-varying parameters,and disturbances.First,by employing the intrinsic properties of Gaussian functions for the interconnection terms for the first time,all extra signals in the framework of decentralized control are filtered out,thereby removing all additional assumptions imposed on the interconnec-tions,such as upper bounding functions and matching conditions.Second,by introducing two integral bounded functions,asymptotic tracking control is realized.Moreover,the nonlinear filters with the compensation terms are introduced to circumvent the issue of“explosion of complexity”.It is shown that all the closed-loop signals are bounded and the tracking errors converge to zero asymptotically.In the end,a simulation example is carried out to demonstrate the effectiveness of the proposed approach.
基金the research grant of the National Natural Science Foundation of China(Grant No.52075125,No.52105331)The research was also partially supported by Shenzhen Science and Technology Innovation Committee(Grant No.JCYJ20210324124203009,No.JSGG20201102154600003,No.GXWD20220818163456002).
文摘The traditional nano-sintering or TLP techniques are generally expensive,time-consuming,and hence unsuitable for realizing practical mass production.Herein,we have developed an improved TLP process to rapidly produce IMC-skeleton structures across the bonding region by initiating a localized liquid-solid interaction among micron particles at traditional soldering temperatures.The developed IMC skeletons can reinforce solder alloys and provide remarkable mechanical stability and electrical capabilities at high temperatures.As a result,the IMC-skeleton strengthened interconnections exhibited higher thermal/electrical conductivity,lower hardness and almost doubled strength than traditional full-IMC joints,attaining 87.4 MPa and 30.2 MPa at room condition and 350℃.Meanwhile,the necessary heating time to form metallurgical bonds was shortened,one-fifth of nano-sintering and one-tenth of TLP bonding,and the material cost was significantly reduced.This proposed technique enabled the fast,low-cost manufacturing of electronics that can serve at temperatures as high as 200−350℃.Besides,the interfacial reactions among particles and the correlated phase evolution process were studied in this research.The formation mechanism of IMC skeletons was analyzed.The correlated influencing factors and their effect on the mechanical,thermal and electrical properties of joints were revealed,which may help the design and extensive uses of such techniques in various high-temperature/power applications.
基金supported by the National Natural Science Foundation of China(Grant No.61904127 and 62004144)Guangdong Basic and Applied Basic Research Foundation(Grant No.2021A1515010651)+2 种基金Fundamental Research Funds for the Central Universities(Grant No.202401002,203134004,20212VA100 and 2021VB006)Hubei Provincial Natural Science Foundation of China(Grant No.2020CFA032)National Key R&D Program of China(Grant No.2019YFB1704600)。
文摘Interconnections in microelectronic packaging are not only the physical carrier to realize the function of electronic circuits,but also the weak spots in reliability tests.Most of failures in power devices are caused by the malfunction of interconnections,including failure of bonding wire as well as cracks of solder layer.In fact,the interconnection failure of power devices is the result of a combination of factors such as electricity,temperature,and force.It is significant to investigate the failure mechanisms of various factors for the failure analysis of interconnections in power devices.This paper reviews the main failure modes of bonding wire and solder layer in the interconnection structure of power devices,and its failure mechanism.Then the reliability test method and failure analysis techniques of interconnection in power device are introduced.These methods are of great significance to the reliability analysis and life prediction of power devices.
基金supported by the State Grid GEIGC Science and Technology Project under the “Research on Global Energy Transition Scenario and Model Development and Application under the New Pattern of Global Environmental Protection” framework(Grant No.52450018000W)
文摘The global water demand and supply situation is becoming increasingly severe due to water shortage and uneven distribution of water resources.The highest water demand in the energy sector is attributable to power generation.With cross-country and cross-continental power grid interconnections becoming a reality,electricity trading across countries and the creation of new opportunities for re-allocation of water resources are possible.This study expands the concept of virtual water and proposes a generalized virtual water flow in an interconnected power grid system to accurately estimate water resource benefits of clean power transmission from both the production and the consumption sides.By defining the water scarcity index as a price mechanism indicator,the benefits of water resources allocation through power grid interconnections are evaluated.Taking the Africa-Asia-Europe interconnection scenario as an example,the total water saving would amount to 88.95 million m^3 by 2030 and 337.8 million m^3 by 2050.This result shows that grid interconnections could promote the development of renewable energy and expand the benefits of available water resources.
文摘This study presents a comprehensive impact analysis of the rotor angle stability of a proposed international connection between the Philippines and Sabah,Malaysia,as part of the Association of Southeast Asian Nations(ASEAN)Power Grid.This study focuses on modeling and evaluating the dynamic performance of the interconnected system,considering the high penetration of renewable sources.Power flow,small signal stability,and transient stability analyses were conducted to assess the ability of the proposed linked power system models to withstand small and large disturbances,utilizing the Power Systems Analysis Toolbox(PSAT)software in MATLAB.All components used in the model are documented in the PSAT library.Currently,there is a lack of publicly available studies regarding the implementation of this specific system.Additionally,the study investigates the behavior of a system with a high penetration of renewable energy sources.Based on the findings,this study concludes that a system is generally stable when interconnection is realized,given its appropriate location and dynamic component parameters.Furthermore,the critical eigenvalues of the system also exhibited improvement as the renewable energy sources were augmented.
基金supported by the National Key R&D Program of China(No.2022YFB2903103)the National Natural Science Foundation of China(No.62205023)。
文摘We propose a cost-effective scheme relying exclusively on pilot symbols for robust frame synchronization and high-precision,wide-range carrier recovery in short-reach optical interconnects.Our method mitigates phase offsets and enhances phase tracking by strategically placing dual-polarization pilot symbols,both aligned and misaligned,within the frame.Compared to traditional carrier recovery schemes,our approach offers a broader frequency offset estimation range,higher carrier recovery accuracy,and significantly lower computational complexity.Experimental results show a 0.7 dB sensitivity improvement at the soft decision forward error correction threshold,outperforming Fourier transform-based frequency offset estimation combined with blind phase search.
基金financially supported by National Natural Science Foundation of China(No.U2241223)Pre-Research Foundation of China(No.909010203-202).
文摘Nano-twinned copper(nt-Cu),with a preferred orientation,is highly promising as interconnect materials in high-density advanced packaging due to its considerable mechanical strength,excellent electrical conductivity,and resistance to thermal migration.However,its application is impeded by sulfur-containing byproducts from the electroplating process,exacerbating the formation of Kirkendall voids within solder joints during thermal aging.Herein,through the incorporation of Zinc(Zn)into the nt-Cu layer,we develop a nt-Cu/Zn composite structure.Our findings provide the first definitive confirmation of the mechanism by which sulfur atoms migrate to the Cu_(3)Sn/nt-Cu interface through interstitial diffusion,thereby reducing the activation energy for vacancy formation.We further demonstrate that Zn effectively an-choring sulfur atoms,forming ZnS within the nt-Cu layer during heat treatment,which increases the vacancy formation energy and inhibits the development of Kirkendall voids.Remarkably,no Kirkendall voids are observed in the modified interconnects even after prolonged aging at 150℃ for 1000 h.The nt-Cu/Zn composite metallization layers significantly decrease the growth rate of interfacial intermetallic compounds by 33.6% and enhance the shear strength of solder interconnections to 228.9%.This research underscores the potential of nt-Cu in advanced electronic packaging,offering new pathways for improving the power density and reliability of electronic devices.
文摘This paper proposes a novel modified uni-traveling-carrier photodiode(MUTC-PD)featuring an electric field regulation layer:a p-type doped thin layer inserted behind the PD’s n-doped cliff layer.This electric field regulation layer enhances the PD’s performance by not only reducing and smoothing the electric field intensity in the collector layer,allowing photo-generated electrons to transit at peak drift velocity,but also improving the electric field intensity in the depleted absorber layer and optimizing the photo-generated carriers’saturated transit performance.Additionally,the transport characteristics of the peak drift velocity of photogenerated electrons in the device’s collection layer can be used to optimize its parasitic characteristics.The electron’s peak drift velocity compensates for the lost transit time.Thus improving the 3 dB bandwidth of the PD’s photo response.Finally obtains a MUTC-PD with a 3 dB bandwidth of 68 GHz at a responsivity of 0.502 A/W,making it suitable for 100 Gbit/s optical receivers.
基金supported by the National Key R&D Program of China(2022YFB4004000)National Natural Science Foundation of China(U24A20542,52472210,22279057)+3 种基金Natural Science Foundation of Jiangsu Province(BK20221312)Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX23_1465)Cultivation Program for the Excellent Doctoral Dissertation of Nanjing Tech University(2023-09)the grant of Hydrogen Energy Laboratory(No.FEUZ-2024-0009)。
文摘As global energy demand increases and environmental standards tighten,the development of efficient,eco-friendly energy conversion and storage technologies becomes crucial.Solid oxide cells(SOCs)show great promise because of their high energy conversion efficiency and wide range of applications.Highentropy materials(HEMs),a novel class of materials comprising several principal elements,have attracted significant interest within the materials science and energy sectors.Their distinctive structural features and adaptable functional properties offer immense potential for innovation across various applications.This review systematically covers the basic concepts,crystal structures,element selection,and major synthesis strategies of HEMs,and explores in detail the specific applications of these materials in SOCs,including its potential as air electrodes,fuel electrodes,electrolytes,and interconnects(including barrier coatings).By analyzing existing studies,this review reveals the significant advantages of HEMs in enhancing the performance,anti-poisoning,and stability of SOCs;highlights the key areas and challenges for future research;and looks into possible future directions.
基金supported in part by the Rosetrees Trust(#CF-2023-I-2_113)by the Israel Ministry of Innovation,Science,and Technology(#7393)(to ES).
文摘The organization of biological neuronal networks into functional modules has intrigued scientists and inspired engineers to develop artificial systems.These networks are characterized by two key properties.First,they exhibit dense interconnectivity(Braitenburg and Schüz,1998;Campagnola et al.,2022).The strength and probability of connectivity depend on cell type,inter-neuronal distance,and species.Still,every cortical neuron receives input from thousands of other neurons while transmitting output to a similar number of neurons.Second,communication between neurons occurs primarily via chemical or electrical synapses.
文摘Industrial intelligence and secure interconnection serve as the foundational platform and critical information infrastructure for new industrialization,carrying significant strategic importance.They not only function as the core engine driving the transformation and upgrading of the manufacturing sector and ensuring stable socioeconomic operation but are also vital to enhancing national technological competitiveness and safeguarding industrial security.
文摘A Malawian perspective on China’s influence,innovation and shared growth In today’s interconnected world,diplomacy,trade,and culture are drawing nations once thought distant closer.A case in point is the growing relationship between Malawi and China-two geographically and historically distinct countries that are finding powerful common ground and shared aspirations.
基金supported by National Key Research and Development Program of China(No.2023YFB2704200)Beijing Natural Science Foundation(No.4254064).
文摘With the rapid development of network technologies,a large number of deployed edge devices and information systems generate massive amounts of data which provide good support for the advancement of data-driven intelligent models.However,these data often contain sensitive information of users.Federated learning(FL),as a privacy preservation machine learning setting,allows users to obtain a well-trained model without sending the privacy-sensitive local data to the central server.Despite the promising prospect of FL,several significant research challenges need to be addressed before widespread deployment,including network resource allocation,model security,model convergence,etc.In this paper,we first provide a brief survey on some of these works that have been done on FL and discuss the motivations of the Communication Networks(CNs)and FL to mutually enable each other.We analyze the support of network technologies for FL,which requires frequent communication and emphasizes security,as well as the studies on the intelligence of many network scenarios and the improvement of network performance and security by the methods based on FL.At last,some challenges and broader perspectives are explored.
基金supported by the National Natural Science Foundation of China(project No 51872298)the fund of the State Key Laboratory of Technologies in Space Cryogenic Pro-pellants(project No SKLTSCP202202)the Strategic Priority Re-search Program of the Chinese Academy of Science(project No XDA22010202).
文摘Multiscale shell structure design is a rational and promising way to regulate the performance of hollow spheres in terms of both functionality and structural robustness,but it remains a big challenge to realize micro-nano engineering of the thin shell while maintaining the low density.In this work,the divisional shell design strategy was adopted to obtain the glass-cobalt-cobalt sulfide composite hollow microspheres(CSH),and an unprecedented stepwise high-temperature chemical reaction-induced aggregation and sub-sequent volume expansion strategy was developed to achieve rational regulation of core-shell structured cobalt-cobalt sulfide building units(BU)assembled on hollow glass microspheres.Special attention has been paid to the sulfidation degree-induced volume control with the underlying mechanism of volume expansion during chemical conversion from metallic cobalt to cobalt sulfide.The electromagnetic prop-erty was found to depend largely on the sulfidation degree due to the volume expansion-induced inter-connecting status regulation among the BU.When evaluated as microwave absorbent,an optimized broad bandwidth of 5.12 GHz and a minimum reflection loss(RLmin)of-45.58 dB of our CSH can be achieved at a thin matching thickness of 1.67 mm and a low filling ratio of 20.04 wt%.In addition to functionality,the divisional shell design also brings the CSH high structural strength(92.36%survival rate at a high hydrostatic pressure of 20 MPa)at low density(0.73 g cm^(-3)).
基金supported by the National Natural Science Foundation of China (Grant Nos. 61925505 and 62405070)"Pioneer" and "Leading Goose" R&D Program of Zhejiang Province (Grant No. 2024C01112)National Key Research and Development Program of China (Grant No. 2023YFB2807100)。
文摘As the demand for computing power in data centers continues to grow, balancing data transmitting speed and energy efficiency has emerged as a critical challenge. Highbandwidth, low-power interconnection schemes are increasingly recognized as core requirements for next-generation intelligent computing center designs^([1, 2]). For short-range optical interconnections of intra-chip and inter-chip—typically covering tens of meters or less—microring resonant modulators (MRM) are emerging as an ideal solution.
文摘Chongqing,the only municipality directly under the central government in China’s central and western regions,is distinguished by its unique identity as both a“mountain city”and a“river city.”Recognized as the birthplace of Bayu culture,an influential ancient culture native to the Chongqing area,the city boasts a recorded history of more than 3,000 years.As a crucial strategic hub in the development of China’s western regions,Chongqing occupies a pivotal position in the interconnected networks fostered by the Belt and Road Initiative and the Yangtze River Economic Belt.Leveraging the golden waterway of the Yangtze River,the China-Europe Railway Express(Chengdu-Chongqing),and the New International Land-Sea Trade Corridor,Chongqing has emerged as a crucial gateway for China’s opening-up.
基金supported by the National Research Foundation of Korea(NRF)grants funded by the Korea government(MSIT)(Nos.RS-2024–00351052 and RS-2024–00450561)。
文摘Metal composites produced through the liquid metal dealloying(LMD)process feature an advanced matrix-matrix composite structure,where two metallic materials form a continuous,three-dimensional interconnected network.This study investigates the effects of Ti Cu precursor compositions on dealloying behavior and microstructural evolution in liquid Mg,using Ti_(50)Cu_(50)and Ti_(30)Cu_(70)precursors.The initial microstructure of the precursor significantly influences dealloying kinetics and phase transitions.The single-phase Ti_(50)Cu_(50)precursor exhibits a faster initial dealloying rate due to its homogeneous structure,yet complete dealloying requires 90 min.In contrast,the dualphase Ti_(30)Cu_(70)precursor achieves complete dealloying in 30 min,demonstrating the impact of a higher Cu concentration on accelerating the process kinetics.Additionally,the study explores the coarsening behavior and hardness variations during the LMD process,along with the microstructural characteristics of Mg-Ti composites fabricated from these two precursors.The findings highlight the critical role of precursor composition in tailoring the microstructure and properties of Mg-Ti composites produced through the LMD process,demonstrating its potential for advanced composite material manufacturing.
基金supported by the National Science Foundation of China under the Grant Nos.12127806 and 62175195the International Joint Research Laboratory for Micro/Nano Manufacturing and Measurement Technologies。
文摘High-density interconnect(HDI)soft electronics that can integrate multiple individual functions into one miniaturized monolithic system is promising for applications related to smart healthcare,soft robotics,and human-machine interactions.However,despite the recent advances,the development of three-dimensional(3D)soft electronics with both high resolution and high integration is still challenging because of the lack of efficient manufacturing methods to guarantee interlayer alignment of the high-density vias and reliable interlayer electrical conductivity.Here,an advanced 3D laser printing pathway,based on femtosecond laser direct writing(FLDW),is demonstrated for preparing liquid metal(LM)-based any layer HDI soft electronics.FLDW technology,with the characteristics of high spatial resolution and high precision,allows the maskless fabrication of high-resolution embedded LM microchannels and high-density vertical interconnect accesses for 3D integrated circuits.High-aspect-ratio blind/through LM microstructures are formed inside the elastomer due to the supermetalphobicity induced during laser ablation.The LM-based HDI circuit featuring high resolution(~1.5μm)and high integration(10-layer electrical interconnection)is achieved for customized soft electronics,including various customized multilayer passive electric components,soft multilayer circuit,and cross-scale multimode sensors.The 3D laser printing method provides a versatile approach for developing chip-level soft electronics.
文摘The competence to distinguish points of view is an essential skill in today’s interconnected and information-rich world.Here’s why it is so important:区分观点的能力是当今互联互通、信息丰富的世界中一项必不可少的技能。以下是它如此重要的原因。
