We observe the influence of AI occupancies in Li sites on the formation process of the garnet solid elec- trolyte of Li_7La_3Zr_2O_12 （LLZO）. A direct incorporation of AI is first promoted in a Li-insufficient garne...We observe the influence of AI occupancies in Li sites on the formation process of the garnet solid elec- trolyte of Li_7La_3Zr_2O_12 （LLZO）. A direct incorporation of AI is first promoted in a Li-insufficient garnet solid electrolyte during the calcination process of 850 ℃ and then the cubic phase of LLZO is obtained after successive annealing step of 1000 ℃. Comparing to pristine LLZO, AI incorporated LLZO shows less formation of Li_2CO_3, keeping crystallographic and physicochemical properties. This AI incorporation im- proves both the ionic conductivity and interfacial resistance to poisoning procedure.展开更多
This paper describes a geographic information system(GIS)-based method for observing changes in topography caused by the initiation, transport, and deposition of debris flows using highresolution light detection and r...This paper describes a geographic information system(GIS)-based method for observing changes in topography caused by the initiation, transport, and deposition of debris flows using highresolution light detection and ranging(LiDAR) digital elevation models(DEMs) obtained before and after the debris flow events. The paper also describes a method for estimating the volume of debris flows using the differences between the LiDAR DEMs. The relative and absolute positioning accuracies of the LiDAR DEMs were evaluated using a real-time precise global navigation satellite system(GNSS) positioning method. In addition, longitudinal and cross-sectional profiles of the study area were constructed to determine the topographic changes caused by the debris flows. The volume of the debris flows was estimated based on the difference between the LiDAR DEMs. The accuracies of the relative and absolute positioning of the two LiDAR DEMs were determined to be ±10 cm and ±11 cm RMSE, respectively, which demonstrates the efficiency of the method for determining topographic changes at an scale equivalent to that of field investigations. Based on the topographic changes, the volume of the debris flows in the study area was estimated to be 3747 m3, which is comparable with the volume estimated based on the data from field investigations.展开更多
The human brain undergoes a complex and dynamic developmental process from birth through adolescence,driven by molecular and cellular mechanisms that shape its structure and function.Magnetic resonance imaging(MRI)has...The human brain undergoes a complex and dynamic developmental process from birth through adolescence,driven by molecular and cellular mechanisms that shape its structure and function.Magnetic resonance imaging(MRI)has become an essential non-invasive tool for studying pediatric brain development and detecting neurological disorders.However,pediatric neuroimaging presents unique challenges,including motion artifacts,small anatomical structures,and immature tissue properties,necessitating specialized MRI techniques.This review provides an overview of recent advancements in MRI hardware,acquisition strategies,and analytical methods optimized for pediatric brain imaging.Furthermore,it summarizes the applications of these techniques in understanding normal brain development,neurodevelopmental disorders,and the impact of early-life risk factors.This review highlights the progresses in pediatric MRI,emphasizing its critical role in advancing our understanding of pediatric brain development and neurological health.It also outlines the challenges and future directions in pediatric MRI to further improve imaging precision and clinical utility.展开更多
Semiconductor microdisk lasers have great potential as low-threshold,high-speed,and small-form-factor light sources required for photonic integrated circuits because of their high-Q factors associated with long-lived ...Semiconductor microdisk lasers have great potential as low-threshold,high-speed,and small-form-factor light sources required for photonic integrated circuits because of their high-Q factors associated with long-lived whispering gallery modes(WGMs).Despite these advantages,the rotational symmetry of the disk shape restricts practical applications of the photonic devices because of their isotropic emission,which lacks directionality in far-field emission and difficulty in free-space out coupling.To overcome this problem,deformation of the disk cavity has been mainly attempted.However,the approach cannot avoid significant Q degradation owing to the broken rotational symmetry.Here,we first report a deformed shape microcavity laser based on transformation optics,which exploits WGMs free from Q degradation.The deformed cavity laser was realized by a spatially varying distribution of deep-sub-wavelength-scale(60 nm diameter)nanoholes in an InGaAsP-based multi-quantum-well heterostructure.The lasing threshold of our laser is one-third of that of the same shaped homogeneous laser and quite similar to that of a homogeneous microdisk laser.The results mean that Q spoiling caused by the boundary shape deformation is recovered by spatially varying nanohole density distribution designed by transformation optics and effective medium approximation.展开更多
基金financial support from the R&D Convergence Program (CAP-14-02-KITECH)the National Research Council of Science & Technology of the Republic of Korea
文摘We observe the influence of AI occupancies in Li sites on the formation process of the garnet solid elec- trolyte of Li_7La_3Zr_2O_12 （LLZO）. A direct incorporation of AI is first promoted in a Li-insufficient garnet solid electrolyte during the calcination process of 850 ℃ and then the cubic phase of LLZO is obtained after successive annealing step of 1000 ℃. Comparing to pristine LLZO, AI incorporated LLZO shows less formation of Li_2CO_3, keeping crystallographic and physicochemical properties. This AI incorporation im- proves both the ionic conductivity and interfacial resistance to poisoning procedure.
基金supported by the Public Welfare & Safety Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning (Grant No. 2012M3A2A1050979)
文摘This paper describes a geographic information system(GIS)-based method for observing changes in topography caused by the initiation, transport, and deposition of debris flows using highresolution light detection and ranging(LiDAR) digital elevation models(DEMs) obtained before and after the debris flow events. The paper also describes a method for estimating the volume of debris flows using the differences between the LiDAR DEMs. The relative and absolute positioning accuracies of the LiDAR DEMs were evaluated using a real-time precise global navigation satellite system(GNSS) positioning method. In addition, longitudinal and cross-sectional profiles of the study area were constructed to determine the topographic changes caused by the debris flows. The volume of the debris flows was estimated based on the difference between the LiDAR DEMs. The accuracies of the relative and absolute positioning of the two LiDAR DEMs were determined to be ±10 cm and ±11 cm RMSE, respectively, which demonstrates the efficiency of the method for determining topographic changes at an scale equivalent to that of field investigations. Based on the topographic changes, the volume of the debris flows in the study area was estimated to be 3747 m3, which is comparable with the volume estimated based on the data from field investigations.
基金supported by the National Natural Science Foundation of China,Grant No.3242780005 and U24 A20754(DW)Key project of Agriculture and social development of Hangzhou,Grant No.20231203 A13(DW)+1 种基金Zhejiang Provincial Natural Science Foundation of China,Grant No.LY24H180002(HXZ)Shanghai Pilot Program for Basic Research—Chinese Academy of Science,Shanghai Branch,Grant No.JCYJ-SHFY-2022-014(HZ).
文摘The human brain undergoes a complex and dynamic developmental process from birth through adolescence,driven by molecular and cellular mechanisms that shape its structure and function.Magnetic resonance imaging(MRI)has become an essential non-invasive tool for studying pediatric brain development and detecting neurological disorders.However,pediatric neuroimaging presents unique challenges,including motion artifacts,small anatomical structures,and immature tissue properties,necessitating specialized MRI techniques.This review provides an overview of recent advancements in MRI hardware,acquisition strategies,and analytical methods optimized for pediatric brain imaging.Furthermore,it summarizes the applications of these techniques in understanding normal brain development,neurodevelopmental disorders,and the impact of early-life risk factors.This review highlights the progresses in pediatric MRI,emphasizing its critical role in advancing our understanding of pediatric brain development and neurological health.It also outlines the challenges and future directions in pediatric MRI to further improve imaging precision and clinical utility.
基金National Research Foundation of Korea(2020R1A2C3007327)Samsung Research Funding Incubation Center of Samsung Electronics(SRFC-IT1062-05)Development of Creative Technology for ICT(22ZB1100)。
文摘Semiconductor microdisk lasers have great potential as low-threshold,high-speed,and small-form-factor light sources required for photonic integrated circuits because of their high-Q factors associated with long-lived whispering gallery modes(WGMs).Despite these advantages,the rotational symmetry of the disk shape restricts practical applications of the photonic devices because of their isotropic emission,which lacks directionality in far-field emission and difficulty in free-space out coupling.To overcome this problem,deformation of the disk cavity has been mainly attempted.However,the approach cannot avoid significant Q degradation owing to the broken rotational symmetry.Here,we first report a deformed shape microcavity laser based on transformation optics,which exploits WGMs free from Q degradation.The deformed cavity laser was realized by a spatially varying distribution of deep-sub-wavelength-scale(60 nm diameter)nanoholes in an InGaAsP-based multi-quantum-well heterostructure.The lasing threshold of our laser is one-third of that of the same shaped homogeneous laser and quite similar to that of a homogeneous microdisk laser.The results mean that Q spoiling caused by the boundary shape deformation is recovered by spatially varying nanohole density distribution designed by transformation optics and effective medium approximation.
