Background Complexity in landscape structure is often assessed using individual metrics related to ecological processes.However,this rarely incorporates important relationships among metrics and may miss landscape str...Background Complexity in landscape structure is often assessed using individual metrics related to ecological processes.However,this rarely incorporates important relationships among metrics and may miss landscape struc‑ture efects.Multivariate statistics provide techniques for assessing overall landscape structure efects.We assessed how multivariate statistics could be used to connect landscape structure with an ecological process[bobcat(Lynx rufus)wildlife crossing structure(WCS)use].We tested how landscape structure at WCS sites compared to the sur‑rounding landscape and how structure afected detections at WCS sites.Our study was conducted in Cameron County,Texas,USA where WCSs are in various stages of construction and monitoring.We used a classifed land use/land cover map and aerial LiDAR to calculate confguration and density metrics at WCS and random sites.We cre‑ated indices for confguration and density using principal components analysis to assess landscape structure efects on camera trap detections at WCSs.Results Landscape structure at WCSs did not difer from random locations.Wildlife crossing structure use increased with greater woody cover and decreased with increasing vegetation density.Our indices allowed identifcation of diferences in how confguration and density impacted WCS use.Ordination methods helped identify individual contributions of landscape metrics to the overall landscape structure efect.Conclusions Wildlife crossing structures are permanent fxtures on landscapes,so selecting appropriate locations using broad-scale landscape structure likely increases target species use.Using indices of landscape structure pro‑vides planners with a more holistic approach to WCS placement and provides a more comprehensive picture of land‑scape pattern and process relationships.展开更多
Planar cross-scale structures encode position and posture,enabling nanometer-level accuracy and multi-scale cascaded precision,emerging as a potential sensing device for semiconductor manufacturing and inspection syst...Planar cross-scale structures encode position and posture,enabling nanometer-level accuracy and multi-scale cascaded precision,emerging as a potential sensing device for semiconductor manufacturing and inspection systems.However,the fabrication of cross-scale hybrid structures,which is the integration of structures spanning three orders of magnitude in feature dimensions(500 nm-1.5 mm)on single substrates,still faces challenges.This requires fabrication of submicron-periodic encoder arrays(reflective regions)and micron-scale non-periodic absolute code tracks(transmissive regions)while maintaining directional consistency.Herein,we demonstrate a mask-interference hybrid lithography method to generate cross-scale structures.The multi-step lithography process integrates interference lithography for fabricating subwavelength periodic structures and mask lithography for patterning millimeter and micrometer-scale non-periodic structures.Alignment marks etched on the mask enable direction consistency between structural zones.The transmissive and reflective structures are differentially processed through region-specific etching and deposition.The effectiveness of this process in realizing the fabrication of hybrid structures is validated through experimental characterization.Moreover,the inherent process scalability establishes a versatile platform for creating multifunctional photonic architectures.展开更多
Urban disaster risks show multi-stage evolution and interconnected coupling features.Under time pressure,case-based reasoning(CBR)has emerged as a critical method for risk management decision making.Case-based reasoni...Urban disaster risks show multi-stage evolution and interconnected coupling features.Under time pressure,case-based reasoning(CBR)has emerged as a critical method for risk management decision making.Case-based reasoning tackles target case problems by leveraging solutions from similar historical cases.However,the current case base is inadequate for storing systemic risk cases,thus impeding CBR efficacy.This article presents a city-level integrated case base with a nested cross structure to facilitate the use of CBR in systemic risk management.It comprises a multi-layer vertical dimension and a multi-scale horizontal dimension.The vertical dimension is optimized to a four-layer(environment-hazard-object-aftermath)risk scenario classification system with taxonomy and fuzzy clustering analysis.The horizontal dimension is improved to a three-scale(network-chain-pair)risk association mode using event chain theory and association analysis.Hazard acts as the pivotal link between the two dimensions.An illustrative example displays the use process of the proposed case base,along with a discussion of its CBR-supported applications.Through the digital transformation,the suggested case base can serve government decision making with CBR,enhancing the city’s capability to reduce systemic risk.展开更多
A low drift current reference based on PMOS temperature correction technology is proposed.To achieve the minimum temperature coefficient(TC),the PMOS cascode current mirror is designed as a cross structure.By exchangi...A low drift current reference based on PMOS temperature correction technology is proposed.To achieve the minimum temperature coefficient(TC),the PMOS cascode current mirror is designed as a cross structure.By exchanging the bias for two layers of the self-biased PMOS cascode structure,the upper PMOS,which is used to adjust the TC together with the resistor of the self-biased PMOS cascode structure,is forced to work in the linear region.As the proposed current reference is the on-chip current reference of a high voltage LED driver with high accuracy,it was designed using a CSMC 1 μm 40 V BCD process.Simulation shows that the TC of the reference current was only 23.8×10 6 /°C over the temperature range of 40-120 °C under the typical condition.展开更多
基金funded by the Texas Department of Transportation.
文摘Background Complexity in landscape structure is often assessed using individual metrics related to ecological processes.However,this rarely incorporates important relationships among metrics and may miss landscape struc‑ture efects.Multivariate statistics provide techniques for assessing overall landscape structure efects.We assessed how multivariate statistics could be used to connect landscape structure with an ecological process[bobcat(Lynx rufus)wildlife crossing structure(WCS)use].We tested how landscape structure at WCS sites compared to the sur‑rounding landscape and how structure afected detections at WCS sites.Our study was conducted in Cameron County,Texas,USA where WCSs are in various stages of construction and monitoring.We used a classifed land use/land cover map and aerial LiDAR to calculate confguration and density metrics at WCS and random sites.We cre‑ated indices for confguration and density using principal components analysis to assess landscape structure efects on camera trap detections at WCSs.Results Landscape structure at WCSs did not difer from random locations.Wildlife crossing structure use increased with greater woody cover and decreased with increasing vegetation density.Our indices allowed identifcation of diferences in how confguration and density impacted WCS use.Ordination methods helped identify individual contributions of landscape metrics to the overall landscape structure efect.Conclusions Wildlife crossing structures are permanent fxtures on landscapes,so selecting appropriate locations using broad-scale landscape structure likely increases target species use.Using indices of landscape structure pro‑vides planners with a more holistic approach to WCS placement and provides a more comprehensive picture of land‑scape pattern and process relationships.
基金supported by the National Natural Science Foundation of China(Grant 62275142)Shenzhen Stable Supporting Program(Grant WDZC20231124201906001).
文摘Planar cross-scale structures encode position and posture,enabling nanometer-level accuracy and multi-scale cascaded precision,emerging as a potential sensing device for semiconductor manufacturing and inspection systems.However,the fabrication of cross-scale hybrid structures,which is the integration of structures spanning three orders of magnitude in feature dimensions(500 nm-1.5 mm)on single substrates,still faces challenges.This requires fabrication of submicron-periodic encoder arrays(reflective regions)and micron-scale non-periodic absolute code tracks(transmissive regions)while maintaining directional consistency.Herein,we demonstrate a mask-interference hybrid lithography method to generate cross-scale structures.The multi-step lithography process integrates interference lithography for fabricating subwavelength periodic structures and mask lithography for patterning millimeter and micrometer-scale non-periodic structures.Alignment marks etched on the mask enable direction consistency between structural zones.The transmissive and reflective structures are differentially processed through region-specific etching and deposition.The effectiveness of this process in realizing the fabrication of hybrid structures is validated through experimental characterization.Moreover,the inherent process scalability establishes a versatile platform for creating multifunctional photonic architectures.
基金supported by the National Natural Science Foundation of China(Grant Nos.72274123,71904121,72004113,72404185)Science and Technology Commission of Shanghai Municipality(Grant Nos.24692104600,23692116200).
文摘Urban disaster risks show multi-stage evolution and interconnected coupling features.Under time pressure,case-based reasoning(CBR)has emerged as a critical method for risk management decision making.Case-based reasoning tackles target case problems by leveraging solutions from similar historical cases.However,the current case base is inadequate for storing systemic risk cases,thus impeding CBR efficacy.This article presents a city-level integrated case base with a nested cross structure to facilitate the use of CBR in systemic risk management.It comprises a multi-layer vertical dimension and a multi-scale horizontal dimension.The vertical dimension is optimized to a four-layer(environment-hazard-object-aftermath)risk scenario classification system with taxonomy and fuzzy clustering analysis.The horizontal dimension is improved to a three-scale(network-chain-pair)risk association mode using event chain theory and association analysis.Hazard acts as the pivotal link between the two dimensions.An illustrative example displays the use process of the proposed case base,along with a discussion of its CBR-supported applications.Through the digital transformation,the suggested case base can serve government decision making with CBR,enhancing the city’s capability to reduce systemic risk.
文摘A low drift current reference based on PMOS temperature correction technology is proposed.To achieve the minimum temperature coefficient(TC),the PMOS cascode current mirror is designed as a cross structure.By exchanging the bias for two layers of the self-biased PMOS cascode structure,the upper PMOS,which is used to adjust the TC together with the resistor of the self-biased PMOS cascode structure,is forced to work in the linear region.As the proposed current reference is the on-chip current reference of a high voltage LED driver with high accuracy,it was designed using a CSMC 1 μm 40 V BCD process.Simulation shows that the TC of the reference current was only 23.8×10 6 /°C over the temperature range of 40-120 °C under the typical condition.
