Anode-free all-solidstate batteries(AFASSBs)are potential candidates for next-generation electric mobility devices that offer superior energy density and stability by eliminating Li from the anode.However,despite its ...Anode-free all-solidstate batteries(AFASSBs)are potential candidates for next-generation electric mobility devices that offer superior energy density and stability by eliminating Li from the anode.However,despite its potential to stabilize the interface between sulfide solid electrolytes(SEs)and anode-free current collectors(CCs)efficiently,a controllable approach to incorporating MoS_(2)into AFASSBs has not yet been found.Herein,we propose a strategy for stabilizing the interface of Li-free all-solid-state batteries using controllable MoS_(2)sacrificial thin films.MoS_(2)was controllably grown on CCs by metal-organic chemical vapor deposition,and the MoS_(2)sacrificial layer in contact with the SEs formed an interlayer composed of Mo metal and Li_(2)S through a conversion reaction.In the AFASSBs with MoS_(2),Mo significantly reduces the nucleation overpotential of Li,which results in uniform Li plating.In addition,MoS_(2)-based Li_(2)S facilitates the formation of a uniform and robust SE interface,thereby enhancing the stability of AFASSBs.Based on these advantages,cells fabricated with MoS_(2)exhibited better performance as both asymmetrical and full cells with LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)cathodes than did cells without MoS_(2).Moreover,the cell performance was affected by the MoS_(2)size,and full cells having an optimal MoS_(2)thickness demonstrated a 1.18-fold increase in the initial discharge capacity and a sevenfold improvement in capacity retention relative to SUS CCs.This study offers a promising path for exploiting the full potential of MoS_(2)for interface stabilization and efficient AFASSB applications.展开更多
Four types of submicron Ag-coated Cu particles with different Ag contents were prepared as sintering paste fillers,and the Ag contents of the particles were measured to be 10,20,30,and 40 wt.%.Four types of particles(...Four types of submicron Ag-coated Cu particles with different Ag contents were prepared as sintering paste fillers,and the Ag contents of the particles were measured to be 10,20,30,and 40 wt.%.Four types of particles(in order of increasing Ag content:A10,A20,A30,and A40)were surface-modified with stearic acid,to suppress the Ag shell dewetting and improve sinterability.The surface-modified particles were mixed with a polyol-based solvent to fabricate a resin-free paste.Subsequently,the pastes were screen-printed onto a slide glass and sintered at 250°C in a nitrogen atmosphere for 1-10 min to form an electrode.The electrical resistivity of the sintered film as a function of sintering time was measured using a four-point probe.All the four surface-modified Cu@Ag particles with different Ag contents exhibited decreased electrical resistivity.Particularly,the largest difference in values after and before the surface modification was observed for A40 with the highest Ag content;the electrical resistivities of the initial and surface-modified particles were 1.51×10^(-4) and 6.67×10^(-5)Ω·cm,respectively,after sintering for 10 min.The findings of this study confirmed that the surface modification using stearic acid effectively suppressed the dewetting of the Ag shell and improved the sinterability of the submicron Cu@Ag particles.展开更多
All-solid-state batteries(ASSBs)with sulfide-type solid electrolytes(SEs)are gaining significant attention due to their potential for the enhanced safety and energy density.In the slurry-coating process for ASSBs,nitr...All-solid-state batteries(ASSBs)with sulfide-type solid electrolytes(SEs)are gaining significant attention due to their potential for the enhanced safety and energy density.In the slurry-coating process for ASSBs,nitrile rubber(NBR)is primarily used as a binder due to its moderate solubility in non-polar solvents,which exhibites minimal chemical reactivity with sulfide SEs.However,the NBR binder,composed of butadiene and acrylonitrile units with differing polarities,exhibits different chemical compatibility depending on the subtle differences in polarity of solvents.Herein,we systematically demonstrate how the chemical compatibility of solvents with the NBR binder influences the performance of ASSBs.Anisole is found to activate the acrylonitrile units,inducing an elongated polymer chain configuration in the binder solution,which gives an opportunity to strongly interact with the solid components of the electrode and the current collector.Consequently,selecting anisole as a solvent for the NBR binder enables the fabrication of a mechanically robust graphite-silicon anode,allowing ASSBs to operate at a lower stacking pressure of 16 MPa.This approach achieves an initial capacity of 480 mAh g^(-1),significantly higher than the 390 mAh g^(-1)achieved with the NBR/toluene binder that has less chemical compatibility.Furthermore,internal stress variations during battery operation are monitored,revealing that the enhanced mechanical properties,achieved through acrylonitrile activation,effectively mitigate internal stress in the graphite/silicon composite anode.展开更多
With electric vehicles(EVs)emerging as a primary mode of transportation,ensuring their reliable operation in harsh environments is crucial.However,lithium-ion batteries(LIBs)suffer from severe polarization at low temp...With electric vehicles(EVs)emerging as a primary mode of transportation,ensuring their reliable operation in harsh environments is crucial.However,lithium-ion batteries(LIBs)suffer from severe polarization at low temperatures,limiting their operation in cold climates.In addition,difficulties in discovering new battery materials have highlighted a growing demand for innovative electrode designs that achieve high performance,even at low temperatu res.To address this issue,we prepared a thin,resistive,and patterned carbon interlayer on the anode current collector.This carbon-patterned layer(CPL)serves as a self-heating layer to efficiently elevate the entire cell temperature,thus improving the rate capability and cyclability at low temperatures while maintaining the performance at room temperature.Furthermore,we validated the versatile applicability of CPLs to large-format LIB cells through experimental studies and electrochemo-thermal multiphysics modeling and simulations,with the results confirming 11%capacity enhancement in 21,700 cylindrical cells at a 0.5C-rate and-24℃.We expect this electrode design to offer reliable power delivery in harsh climates,thereby potentially expanding the applications of LIBs.展开更多
All-solid-state batteries(ASSBs)are a promising next-generation energy storage solution due to their high energy density and enhanced safety.To achieve this,specialized electrode designs are required to efficiently en...All-solid-state batteries(ASSBs)are a promising next-generation energy storage solution due to their high energy density and enhanced safety.To achieve this,specialized electrode designs are required to efficiently enhance interparticle lithium-ion transport between solid components.In particular,for active materials with high specific capacity,such as silicon,their volume expansion and shrinkage must be carefully controlled to maintain mechanical interface stability,which is crucial for effective lithium-ion transport in ASSBs.Herein,we propose a mechanical stress-tolerant all-solid-state graphite/silicon electrode design to ensure stable lithium-ion diffusion at the interface through morphology control of active material particles.Plate-type graphite with a high surface-area-to-volume ratio is used to maximize the dispersion of silicon within the electrode.The carefully designed electrode can accommodate the volume changes of silicon,ensuring stable capacity retention over cycles.Additionally,spherical graphite is shown to contribute to improved rate performance by providing an efficient lithium-ion diffusion pathway within the electrode.Therefore,the synergistic effect of our electrode structure offers balanced electrochemical performance,providing practical insights into the mechano-electrochemical interactions essential for designing highperformance all-solid-state electrodes.展开更多
Security vulnerability of denial of service (DoS) in time out-medium access control (T-MAC) protocol was discussed and analysis of power consumption at each stage of T-MAC protocol was carried out. For power efficient...Security vulnerability of denial of service (DoS) in time out-medium access control (T-MAC) protocol was discussed and analysis of power consumption at each stage of T-MAC protocol was carried out. For power efficient authentication scheme which can provide reliability, efficiency, and security for a general T-MAC communication, a novel synchronization and authentication scheme using authentication masking code was proposed. Authentication data were repeated and masked by PN sequence. The simulation results show that the proposed approach can provide synchronization and authentication simultaneously for nodes in wireless sensor network (WSN). 63 bits AMC code gives above 99.97% synchronization detection and 93.98% authentication data detection probability in BER 0.031 7.展开更多
A substantial body of work has been done to identify network anomalies using supervised and unsupervised learning techniques with their unique strengths and weaknesses.In this work,we propose a new approach that takes...A substantial body of work has been done to identify network anomalies using supervised and unsupervised learning techniques with their unique strengths and weaknesses.In this work,we propose a new approach that takes advantage of both worlds of unsupervised and supervised learnings.The main objective of the proposed approach is to enable supervised anomaly detection without the provision of the associated labels by users.To this end,we estimate the labels of each connection in the training phase using clustering.The“estimated”labels are then utilized to establish a supervised learning model for the subsequent classification of connections in the testing stage.We set up a new property that defines anomalies in the context of network anomaly detection to improve the quality of estimated labels.Through our extensive experiments with a public dataset(NSL-KDD),we will prove that the proposed method can achieve performance comparable to one with the “original”labels provided in the dataset.We also introduce two heuristic functions that minimize the impact of the randomness of clustering to improve the overall quality of the estimated labels.展开更多
We propose a mobile system,called PotholeEye+,for automatically monitoring the surface of a roadway and detecting the pavement distress in real-time through analysis of a video.PotholeEye+pre-processes the images,extr...We propose a mobile system,called PotholeEye+,for automatically monitoring the surface of a roadway and detecting the pavement distress in real-time through analysis of a video.PotholeEye+pre-processes the images,extracts features,and classifies the distress into a variety of types,while the road manager is driving.Every day for a year,we have tested PotholeEye+on real highway involving real settings,a camera,a mini computer,a GPS receiver,and so on.Consequently,PotholeEye+detected the pavement distress with accuracy of 92%,precision of 87%and recall 74%averagely during driving at an average speed of 110 km/h on a real highway.展开更多
Though the WiMedia supports higher data rates than other WPAN technologies,a WiMedia device cannot reach other devices that are separated from it by more than 10 m,which is the typical limited transmission range of th...Though the WiMedia supports higher data rates than other WPAN technologies,a WiMedia device cannot reach other devices that are separated from it by more than 10 m,which is the typical limited transmission range of the WiMedia protocol.In this work,we propose a multi-hop QoS routing protocol to enable WiMedia devices to transmit real-time data to devices that are located out of the transmission range.The proposed routing protocol is a hybrid algorithm,which mixes the table-driven and on-demand routing algorithms,searching one or more routes according to the number of hops to a destination device.WiMedia MAC is potentially capable of learning the existence of neighbor devices by using a beacon frame.By utilizing the neighbors' information,all devices can create routing entries for devices within 2-hops periodically.For devices beyond the 2-hop range,the newly designed on-demand routing algorithm is applied to multi-hop routing.If a routing entry for a destination device is not listed in the routing table,the source device sends a request packet to 2-hop range devices which could be found in the routing table.Since every device maintains routing entries for 2-hop range devices in the routing table,the request packet is replied in advance before its arrival at the destination device.Also,to decide the optimal route for a destination device,the number of medium access slots(MASs),received signal strength indicator(RSSI)and hop count are utilized to establish a QoS-enabled routing table.We perform ns-2 simulation to investigate the performance of the proposed routing protocol with AODV and DSDV.The simulation results show that the proposed protocol has better throughput and lower overhead than other protocols.展开更多
Service mobility has become a new issue in the area of service convergence with the advent of versatile mobile devices. Hence, we propose an open service framework with support for service mobility that executes conte...Service mobility has become a new issue in the area of service convergence with the advent of versatile mobile devices. Hence, we propose an open service framework with support for service mobility that executes contents and applications in a dynamic environment. For the framework, the concept and role of a device and its application for a service are redefined into the new concepts of device, execution engine, and service. Mechanisms for device profiling, user preference learning, and profile-based service recommendation are designed to enable device-capability-aware service recommendation functionality. Furthermore, a seamless service syndication mechanism is added for continuity and synchronization of service upon change of terminal, network status, or personal preference. A prototype system integrates functionalities with proprietary protocol and a content transcoder to support multiple device platforms. The prototype shows the capability of the framework in service mobility support and its advancement into an open international application platform.展开更多
In the present technological world,surveillance cameras generate an immense amount of video data from various sources,making its scrutiny tough for computer vision specialists.It is difficult to search for anomalous e...In the present technological world,surveillance cameras generate an immense amount of video data from various sources,making its scrutiny tough for computer vision specialists.It is difficult to search for anomalous events manually in thesemassive video records since they happen infrequently and with a low probability in real-world monitoring systems.Therefore,intelligent surveillance is a requirement of the modern day,as it enables the automatic identification of normal and aberrant behavior using artificial intelligence and computer vision technologies.In this article,we introduce an efficient Attention-based deep-learning approach for anomaly detection in surveillance video(ADSV).At the input of the ADSV,a shots boundary detection technique is used to segment prominent frames.Next,The Lightweight ConvolutionNeuralNetwork(LWCNN)model receives the segmented frames to extract spatial and temporal information from the intermediate layer.Following that,spatial and temporal features are learned using Long Short-Term Memory(LSTM)cells and Attention Network from a series of frames for each anomalous activity in a sample.To detect motion and action,the LWCNN received chronologically sorted frames.Finally,the anomaly activity in the video is identified using the proposed trained ADSV model.Extensive experiments are conducted on complex and challenging benchmark datasets.In addition,the experimental results have been compared to state-ofthe-artmethodologies,and a significant improvement is attained,demonstrating the efficiency of our ADSV method.展开更多
Interference cancellation system (ICS) for 3GPP/LTE system is the broadband cancellation system, which receives forward signal through the donor antenna. We proposed new algorithm of received signal with pilot and non...Interference cancellation system (ICS) for 3GPP/LTE system is the broadband cancellation system, which receives forward signal through the donor antenna. We proposed new algorithm of received signal with pilot and non-pilot design. Although repeater design needs our project, so in this paper we discuss about interference cancellation algorithm for 2x2 MIMO systems without pilot in LTE. First explain the general principle structure of 3GPP/LTE, next determine our new design and algorithm. Finally, we simulated our mathematic extraction of proposed new algorithm on MATLAB.展开更多
HWANG Jenq-Neng received his Ph.D. degree from the University of Southern California, USA. In the summer of 1989, Dr. HWANG joined the De- partment of Electrical Engineering of the Universi- ty of Washington in Seattl...HWANG Jenq-Neng received his Ph.D. degree from the University of Southern California, USA. In the summer of 1989, Dr. HWANG joined the De- partment of Electrical Engineering of the Universi- ty of Washington in Seattle, USA, where he has been promoted to Full Professor since 1999. He served as the Associate Chair for Research fi＇om 2003 to 2005, and from 2011-2015. He is current- ly the Associate Chair for Global Affairs and Inter- national Development in the EE Depamnent. Hehas written more than 330 journal papers, conference papers and book chapters in the areas of machine learning, muhimedia signal processing, and muhimedia system integration and networking, including an au- thored textbook on ＂Multimedia Networking： from Theory to Practice,＂ published by Cambridge University Press. Dr. HWANG has close work- ing relationship with the industry on muhimedia signal processing and nmltimedia networking.展开更多
The diagnosis of ocular myasthenia gravis is rarely in doubt in patients with a proper history and typical clinical findings. However, myasthenia gravis can mimick any pupil- sparing eye movement disorder and several ...The diagnosis of ocular myasthenia gravis is rarely in doubt in patients with a proper history and typical clinical findings. However, myasthenia gravis can mimick any pupil- sparing eye movement disorder and several diseases may masquerade myasthenia g ravis. We review the atypical presentations and differential diagnoses in ocular myasthenia gravis, describing four patients with some of these conditions (4th nerve palsy, near spasm reflex, one-and-a-half syndrome, orbital meningioma). The correct interpretation of the clinical findings associated with appropriate neuro-imaging studies allowed the appropriate diagnosis in these cases.展开更多
Vascular endothelial growth factor (VEGF) is considered to play an es sential role in the pathogenesis of age-relatedma- cular degeneration due to its vascular permeability-inducing and angiogenic p roperties. Ranibiz...Vascular endothelial growth factor (VEGF) is considered to play an es sential role in the pathogenesis of age-relatedma- cular degeneration due to its vascular permeability-inducing and angiogenic p roperties. Ranibizumab, a small antibody fragment designed to competitively bind all VEGF isoforms, passes after intravitreal injection all retinal layers reach ing the retinal pigment epithelium-choroid complex. Experimental animal models showed the drug to be safe and effective. Subsequently, Phase I/II clinical tria ls conducted in patients with neovascular AMDdemonstrated a good safety profile, and a significant functional benefit. Ranibizumab therapy repeated every four we eks for the treatment of neovascular AMD is currently in Phase III clinical tria ls. Combination therapy trials aiming for improved treatment durability and effe ctiveness are currently ongoing as well as new treatment strategies using interm ittent, optical coherence tomography (OCT) guided therapy. Anti-VEGF therapy us ingRanibizumab is a promising newtreatment option for neovascular AMD.展开更多
The increasing demand for short charging time on electric vehicles has motivated realization of fast chargeable lithium-ion batteries(LIBs).However,shortening the charging time of LIBs is limited by Li^(+)intercalatio...The increasing demand for short charging time on electric vehicles has motivated realization of fast chargeable lithium-ion batteries(LIBs).However,shortening the charging time of LIBs is limited by Li^(+)intercalation process consisting of liquid-phase diffusion,de-solvation,SEI crossing,and solid-phase diffusion.Herein,we propose a new strategy to accelerate the de-solvation step through a control of interaction between polymeric binder and solvent-Li^(+)complexes.For this purpose,three alkali metal ions(Li^(+),Na^(+),and K^(+))substituted carboxymethyl cellulose(Li-,Na-,and K-CMC)are prepared to examine the effects of metal ions on their performances.The lowest activation energy of de-solvation and the highest chemical diffusion coefficient were observed for Li-CMC.Specifically,Li-CMC cell with a capacity of 3 mAh cm^(-2)could be charged to>95%in 10 min,while a value above>85%was observed after 150 cycles.Thus,the presented approach holds great promise for the realization of fast charging.展开更多
Customer relationship management systems are gaining importance in today's business environment since customer satisfaction is crucial to the success of an enterprise, and especially so in e-business environment w...Customer relationship management systems are gaining importance in today's business environment since customer satisfaction is crucial to the success of an enterprise, and especially so in e-business environment where customers can find substitute suppliers quite easily. In CRM, the quality of customer information is very important, and the address information even more so. It is because the address information plays a major role for customer contact channel and for timely and effective marketing service. Furthermore, it gives the basic source of geographic information for the offline delivery, the terminal activity of the e-commerce. In this study, we analyze various standards and proposals for the address information, and propose data models for the management of the information focusing on address components, and proto-type systems for management and service.展开更多
基金supported by National Research Foundation of Korea (NRF) grants funded by the Korea government (MSIT)(RS-2022-NR072281)the financial support from the Development of Smart Chemical Materials for Io T Devices Project (KS2521-10) through the Korea Research Institute of Chemical Technologysupported by the National Research Foundation of the Republic of Korea (Project Nos. RS-2023-00217581 and RS-2024-00406724)
文摘Anode-free all-solidstate batteries(AFASSBs)are potential candidates for next-generation electric mobility devices that offer superior energy density and stability by eliminating Li from the anode.However,despite its potential to stabilize the interface between sulfide solid electrolytes(SEs)and anode-free current collectors(CCs)efficiently,a controllable approach to incorporating MoS_(2)into AFASSBs has not yet been found.Herein,we propose a strategy for stabilizing the interface of Li-free all-solid-state batteries using controllable MoS_(2)sacrificial thin films.MoS_(2)was controllably grown on CCs by metal-organic chemical vapor deposition,and the MoS_(2)sacrificial layer in contact with the SEs formed an interlayer composed of Mo metal and Li_(2)S through a conversion reaction.In the AFASSBs with MoS_(2),Mo significantly reduces the nucleation overpotential of Li,which results in uniform Li plating.In addition,MoS_(2)-based Li_(2)S facilitates the formation of a uniform and robust SE interface,thereby enhancing the stability of AFASSBs.Based on these advantages,cells fabricated with MoS_(2)exhibited better performance as both asymmetrical and full cells with LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)cathodes than did cells without MoS_(2).Moreover,the cell performance was affected by the MoS_(2)size,and full cells having an optimal MoS_(2)thickness demonstrated a 1.18-fold increase in the initial discharge capacity and a sevenfold improvement in capacity retention relative to SUS CCs.This study offers a promising path for exploiting the full potential of MoS_(2)for interface stabilization and efficient AFASSB applications.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.2021R1A2C1007400)supported,partly,by the National R&D Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT(Nos.NRF-2020M3H4A3106383,NRF2020M3H4A3081764)+1 种基金supported,partly,by ETRI(No.21YB1610)supported by a Korea Institute for Advancement of Technology(KIAT)grant funded by the Korea Government(MOTIE)(No.P0008458,HRD Program for Industrial Innovation)。
文摘Four types of submicron Ag-coated Cu particles with different Ag contents were prepared as sintering paste fillers,and the Ag contents of the particles were measured to be 10,20,30,and 40 wt.%.Four types of particles(in order of increasing Ag content:A10,A20,A30,and A40)were surface-modified with stearic acid,to suppress the Ag shell dewetting and improve sinterability.The surface-modified particles were mixed with a polyol-based solvent to fabricate a resin-free paste.Subsequently,the pastes were screen-printed onto a slide glass and sintered at 250°C in a nitrogen atmosphere for 1-10 min to form an electrode.The electrical resistivity of the sintered film as a function of sintering time was measured using a four-point probe.All the four surface-modified Cu@Ag particles with different Ag contents exhibited decreased electrical resistivity.Particularly,the largest difference in values after and before the surface modification was observed for A40 with the highest Ag content;the electrical resistivities of the initial and surface-modified particles were 1.51×10^(-4) and 6.67×10^(-5)Ω·cm,respectively,after sintering for 10 min.The findings of this study confirmed that the surface modification using stearic acid effectively suppressed the dewetting of the Ag shell and improved the sinterability of the submicron Cu@Ag particles.
基金supported by the Technology Innovation Program(00404166,Development of thin-film coating current collector and aqueous binder to enhance the adhesion and conductivity properties on the silicon-rich anode)funded By the Ministry of Trade,Industry&Energy(MOTIE,Korea),the National Research Council of Science&Technology(NST)grant by the Korea government(MSIT)(No.2710024139)the Institute of Civil Military Technology Cooperation funded by the Defense Acquisition Program Administration and Ministry of Trade,Industry and Energy of Korean government under grant No.22-CM-FC-20。
文摘All-solid-state batteries(ASSBs)with sulfide-type solid electrolytes(SEs)are gaining significant attention due to their potential for the enhanced safety and energy density.In the slurry-coating process for ASSBs,nitrile rubber(NBR)is primarily used as a binder due to its moderate solubility in non-polar solvents,which exhibites minimal chemical reactivity with sulfide SEs.However,the NBR binder,composed of butadiene and acrylonitrile units with differing polarities,exhibits different chemical compatibility depending on the subtle differences in polarity of solvents.Herein,we systematically demonstrate how the chemical compatibility of solvents with the NBR binder influences the performance of ASSBs.Anisole is found to activate the acrylonitrile units,inducing an elongated polymer chain configuration in the binder solution,which gives an opportunity to strongly interact with the solid components of the electrode and the current collector.Consequently,selecting anisole as a solvent for the NBR binder enables the fabrication of a mechanically robust graphite-silicon anode,allowing ASSBs to operate at a lower stacking pressure of 16 MPa.This approach achieves an initial capacity of 480 mAh g^(-1),significantly higher than the 390 mAh g^(-1)achieved with the NBR/toluene binder that has less chemical compatibility.Furthermore,internal stress variations during battery operation are monitored,revealing that the enhanced mechanical properties,achieved through acrylonitrile activation,effectively mitigate internal stress in the graphite/silicon composite anode.
基金financially supported by the Institute of Civil Military Technology Cooperation funded by the Defense Acquisition Program Administration and Ministry of Trade,Industry and Energy of Korean government under grant No.22-CM-FC-20the support from the DGIST Supercomputing and Bigdata Center。
文摘With electric vehicles(EVs)emerging as a primary mode of transportation,ensuring their reliable operation in harsh environments is crucial.However,lithium-ion batteries(LIBs)suffer from severe polarization at low temperatures,limiting their operation in cold climates.In addition,difficulties in discovering new battery materials have highlighted a growing demand for innovative electrode designs that achieve high performance,even at low temperatu res.To address this issue,we prepared a thin,resistive,and patterned carbon interlayer on the anode current collector.This carbon-patterned layer(CPL)serves as a self-heating layer to efficiently elevate the entire cell temperature,thus improving the rate capability and cyclability at low temperatures while maintaining the performance at room temperature.Furthermore,we validated the versatile applicability of CPLs to large-format LIB cells through experimental studies and electrochemo-thermal multiphysics modeling and simulations,with the results confirming 11%capacity enhancement in 21,700 cylindrical cells at a 0.5C-rate and-24℃.We expect this electrode design to offer reliable power delivery in harsh climates,thereby potentially expanding the applications of LIBs.
基金supported by the National Research Council of Science&Technology(NST)grant by the Korea government(MSIT)(No.GTL24011-000)the National Research Foundation of Korea(NRF2022M3J1A1085396)the Technology Innovation Program(RS-2024-00445442)through the Korea Planning&Evaluation Institute of Industrial Technology(KEIT)funded by the Ministry of Trade,Industry&Energy(MOTIE,Korea).
文摘All-solid-state batteries(ASSBs)are a promising next-generation energy storage solution due to their high energy density and enhanced safety.To achieve this,specialized electrode designs are required to efficiently enhance interparticle lithium-ion transport between solid components.In particular,for active materials with high specific capacity,such as silicon,their volume expansion and shrinkage must be carefully controlled to maintain mechanical interface stability,which is crucial for effective lithium-ion transport in ASSBs.Herein,we propose a mechanical stress-tolerant all-solid-state graphite/silicon electrode design to ensure stable lithium-ion diffusion at the interface through morphology control of active material particles.Plate-type graphite with a high surface-area-to-volume ratio is used to maximize the dispersion of silicon within the electrode.The carefully designed electrode can accommodate the volume changes of silicon,ensuring stable capacity retention over cycles.Additionally,spherical graphite is shown to contribute to improved rate performance by providing an efficient lithium-ion diffusion pathway within the electrode.Therefore,the synergistic effect of our electrode structure offers balanced electrochemical performance,providing practical insights into the mechano-electrochemical interactions essential for designing highperformance all-solid-state electrodes.
文摘Security vulnerability of denial of service (DoS) in time out-medium access control (T-MAC) protocol was discussed and analysis of power consumption at each stage of T-MAC protocol was carried out. For power efficient authentication scheme which can provide reliability, efficiency, and security for a general T-MAC communication, a novel synchronization and authentication scheme using authentication masking code was proposed. Authentication data were repeated and masked by PN sequence. The simulation results show that the proposed approach can provide synchronization and authentication simultaneously for nodes in wireless sensor network (WSN). 63 bits AMC code gives above 99.97% synchronization detection and 93.98% authentication data detection probability in BER 0.031 7.
基金This work was supported in part by Institute of Information and Communications Technology Promotion(ITP)grant funded by the Korea government(MSIP)(No.2016-0-00078,Cloud-based Security In-telligence Technology Development for the Customized Security Service Provisioning)。
文摘A substantial body of work has been done to identify network anomalies using supervised and unsupervised learning techniques with their unique strengths and weaknesses.In this work,we propose a new approach that takes advantage of both worlds of unsupervised and supervised learnings.The main objective of the proposed approach is to enable supervised anomaly detection without the provision of the associated labels by users.To this end,we estimate the labels of each connection in the training phase using clustering.The“estimated”labels are then utilized to establish a supervised learning model for the subsequent classification of connections in the testing stage.We set up a new property that defines anomalies in the context of network anomaly detection to improve the quality of estimated labels.Through our extensive experiments with a public dataset(NSL-KDD),we will prove that the proposed method can achieve performance comparable to one with the “original”labels provided in the dataset.We also introduce two heuristic functions that minimize the impact of the randomness of clustering to improve the overall quality of the estimated labels.
文摘We propose a mobile system,called PotholeEye+,for automatically monitoring the surface of a roadway and detecting the pavement distress in real-time through analysis of a video.PotholeEye+pre-processes the images,extracts features,and classifies the distress into a variety of types,while the road manager is driving.Every day for a year,we have tested PotholeEye+on real highway involving real settings,a camera,a mini computer,a GPS receiver,and so on.Consequently,PotholeEye+detected the pavement distress with accuracy of 92%,precision of 87%and recall 74%averagely during driving at an average speed of 110 km/h on a real highway.
基金Project supported by the Second Stage of Brain Korea 21 ProjectsProject(10035236)supported by the IT_R&D Program of MKE/KEIT,Korea
文摘Though the WiMedia supports higher data rates than other WPAN technologies,a WiMedia device cannot reach other devices that are separated from it by more than 10 m,which is the typical limited transmission range of the WiMedia protocol.In this work,we propose a multi-hop QoS routing protocol to enable WiMedia devices to transmit real-time data to devices that are located out of the transmission range.The proposed routing protocol is a hybrid algorithm,which mixes the table-driven and on-demand routing algorithms,searching one or more routes according to the number of hops to a destination device.WiMedia MAC is potentially capable of learning the existence of neighbor devices by using a beacon frame.By utilizing the neighbors' information,all devices can create routing entries for devices within 2-hops periodically.For devices beyond the 2-hop range,the newly designed on-demand routing algorithm is applied to multi-hop routing.If a routing entry for a destination device is not listed in the routing table,the source device sends a request packet to 2-hop range devices which could be found in the routing table.Since every device maintains routing entries for 2-hop range devices in the routing table,the request packet is replied in advance before its arrival at the destination device.Also,to decide the optimal route for a destination device,the number of medium access slots(MASs),received signal strength indicator(RSSI)and hop count are utilized to establish a QoS-enabled routing table.We perform ns-2 simulation to investigate the performance of the proposed routing protocol with AODV and DSDV.The simulation results show that the proposed protocol has better throughput and lower overhead than other protocols.
文摘Service mobility has become a new issue in the area of service convergence with the advent of versatile mobile devices. Hence, we propose an open service framework with support for service mobility that executes contents and applications in a dynamic environment. For the framework, the concept and role of a device and its application for a service are redefined into the new concepts of device, execution engine, and service. Mechanisms for device profiling, user preference learning, and profile-based service recommendation are designed to enable device-capability-aware service recommendation functionality. Furthermore, a seamless service syndication mechanism is added for continuity and synchronization of service upon change of terminal, network status, or personal preference. A prototype system integrates functionalities with proprietary protocol and a content transcoder to support multiple device platforms. The prototype shows the capability of the framework in service mobility support and its advancement into an open international application platform.
基金This research was supported by the Chung-Ang University Research Scholarship Grants in 2021 and the Culture,Sports and Tourism R&D Program through the Korea Creative Content Agency grant funded by the Ministry of Culture,Sports,and Tourism in 2022(Project Name:Development of Digital Quarantine and Operation Technologies for Creation of Safe Viewing Environment in Cultural Facilities,Project Number:R2021040028,Contribution Rate:100%).
文摘In the present technological world,surveillance cameras generate an immense amount of video data from various sources,making its scrutiny tough for computer vision specialists.It is difficult to search for anomalous events manually in thesemassive video records since they happen infrequently and with a low probability in real-world monitoring systems.Therefore,intelligent surveillance is a requirement of the modern day,as it enables the automatic identification of normal and aberrant behavior using artificial intelligence and computer vision technologies.In this article,we introduce an efficient Attention-based deep-learning approach for anomaly detection in surveillance video(ADSV).At the input of the ADSV,a shots boundary detection technique is used to segment prominent frames.Next,The Lightweight ConvolutionNeuralNetwork(LWCNN)model receives the segmented frames to extract spatial and temporal information from the intermediate layer.Following that,spatial and temporal features are learned using Long Short-Term Memory(LSTM)cells and Attention Network from a series of frames for each anomalous activity in a sample.To detect motion and action,the LWCNN received chronologically sorted frames.Finally,the anomaly activity in the video is identified using the proposed trained ADSV model.Extensive experiments are conducted on complex and challenging benchmark datasets.In addition,the experimental results have been compared to state-ofthe-artmethodologies,and a significant improvement is attained,demonstrating the efficiency of our ADSV method.
文摘Interference cancellation system (ICS) for 3GPP/LTE system is the broadband cancellation system, which receives forward signal through the donor antenna. We proposed new algorithm of received signal with pilot and non-pilot design. Although repeater design needs our project, so in this paper we discuss about interference cancellation algorithm for 2x2 MIMO systems without pilot in LTE. First explain the general principle structure of 3GPP/LTE, next determine our new design and algorithm. Finally, we simulated our mathematic extraction of proposed new algorithm on MATLAB.
文摘HWANG Jenq-Neng received his Ph.D. degree from the University of Southern California, USA. In the summer of 1989, Dr. HWANG joined the De- partment of Electrical Engineering of the Universi- ty of Washington in Seattle, USA, where he has been promoted to Full Professor since 1999. He served as the Associate Chair for Research fi＇om 2003 to 2005, and from 2011-2015. He is current- ly the Associate Chair for Global Affairs and Inter- national Development in the EE Depamnent. Hehas written more than 330 journal papers, conference papers and book chapters in the areas of machine learning, muhimedia signal processing, and muhimedia system integration and networking, including an au- thored textbook on ＂Multimedia Networking： from Theory to Practice,＂ published by Cambridge University Press. Dr. HWANG has close work- ing relationship with the industry on muhimedia signal processing and nmltimedia networking.
文摘The diagnosis of ocular myasthenia gravis is rarely in doubt in patients with a proper history and typical clinical findings. However, myasthenia gravis can mimick any pupil- sparing eye movement disorder and several diseases may masquerade myasthenia g ravis. We review the atypical presentations and differential diagnoses in ocular myasthenia gravis, describing four patients with some of these conditions (4th nerve palsy, near spasm reflex, one-and-a-half syndrome, orbital meningioma). The correct interpretation of the clinical findings associated with appropriate neuro-imaging studies allowed the appropriate diagnosis in these cases.
文摘Vascular endothelial growth factor (VEGF) is considered to play an es sential role in the pathogenesis of age-relatedma- cular degeneration due to its vascular permeability-inducing and angiogenic p roperties. Ranibizumab, a small antibody fragment designed to competitively bind all VEGF isoforms, passes after intravitreal injection all retinal layers reach ing the retinal pigment epithelium-choroid complex. Experimental animal models showed the drug to be safe and effective. Subsequently, Phase I/II clinical tria ls conducted in patients with neovascular AMDdemonstrated a good safety profile, and a significant functional benefit. Ranibizumab therapy repeated every four we eks for the treatment of neovascular AMD is currently in Phase III clinical tria ls. Combination therapy trials aiming for improved treatment durability and effe ctiveness are currently ongoing as well as new treatment strategies using interm ittent, optical coherence tomography (OCT) guided therapy. Anti-VEGF therapy us ingRanibizumab is a promising newtreatment option for neovascular AMD.
基金supported by Electronics and Telecommunications Research Institute(ETRI)grant funded by the Korea government(20ZB1200,Development of ICT Materials,Components and Equipment Technologies)the National Research Foundation of Korea(NRF)grant funded by the Korea government(No.2020R1A4A4079810)funding from the National Research Foundation(NRF)funded by the Ministry of Science and ICT,Rep.of Korea(Project No.2021R1C1C1008776)
文摘The increasing demand for short charging time on electric vehicles has motivated realization of fast chargeable lithium-ion batteries(LIBs).However,shortening the charging time of LIBs is limited by Li^(+)intercalation process consisting of liquid-phase diffusion,de-solvation,SEI crossing,and solid-phase diffusion.Herein,we propose a new strategy to accelerate the de-solvation step through a control of interaction between polymeric binder and solvent-Li^(+)complexes.For this purpose,three alkali metal ions(Li^(+),Na^(+),and K^(+))substituted carboxymethyl cellulose(Li-,Na-,and K-CMC)are prepared to examine the effects of metal ions on their performances.The lowest activation energy of de-solvation and the highest chemical diffusion coefficient were observed for Li-CMC.Specifically,Li-CMC cell with a capacity of 3 mAh cm^(-2)could be charged to>95%in 10 min,while a value above>85%was observed after 150 cycles.Thus,the presented approach holds great promise for the realization of fast charging.
文摘Customer relationship management systems are gaining importance in today's business environment since customer satisfaction is crucial to the success of an enterprise, and especially so in e-business environment where customers can find substitute suppliers quite easily. In CRM, the quality of customer information is very important, and the address information even more so. It is because the address information plays a major role for customer contact channel and for timely and effective marketing service. Furthermore, it gives the basic source of geographic information for the offline delivery, the terminal activity of the e-commerce. In this study, we analyze various standards and proposals for the address information, and propose data models for the management of the information focusing on address components, and proto-type systems for management and service.
