Typhoons can cause large-area blackouts or partial outages of distribution networks.We define a partial outage state in the distribution network as a gray state and propose a gray-start strategy and two-stage distribu...Typhoons can cause large-area blackouts or partial outages of distribution networks.We define a partial outage state in the distribution network as a gray state and propose a gray-start strategy and two-stage distribution network emergency recovery framework.A phase-space reconstruction and stacked integrated model for predicting wind and photovoltaic generation during typhoon disasters is proposed in the first stage.This provides guidance for second-stage post-disaster emergency recovery scheduling.The emergency recovery scheduling model is established in the second stage,and this model is supported by a thermal power-generating unit,mobile emergency generators,and distributed generators.Distributed generation includes wind power generation,photovoltaics,fuel cells,etc.Simultaneously,we con-sider the gray-start based on the pumped storage unit to be an important first step in the emergency recovery strategy.This model is val-idated on the improved IEEE 33 node system,which utilizes data from the 2022 super typhoon“Muifa”in Zhoushan,Zhejiang,China.Simulations indicate the superiority of a gray start with a pumped storage unit and the proposed emergency recovery strategy.展开更多
Different types of lightning air terminals have been designed over the years.Concern regarding the effect of different types of air terminals,especially the early streamer emission(ESE)-type,remains controversial.This...Different types of lightning air terminals have been designed over the years.Concern regarding the effect of different types of air terminals,especially the early streamer emission(ESE)-type,remains controversial.This paper describes the discharge characteristics of different types of air terminals,two of which are quite similar to the ESE-type dynasphere,and concludes that the tested non-standard air terminals have discharge characteristics similar to those of Franklin rods and that their lightning protection performance should be similar.展开更多
Carbohydrate metabolism disorders(CMDs),such as diabetes,galactosemia,and mannosidosis,cause ciliopathy-like multiorgan defects.However,the mechanistic link of cilia to CMD complications is still poorly understood.Her...Carbohydrate metabolism disorders(CMDs),such as diabetes,galactosemia,and mannosidosis,cause ciliopathy-like multiorgan defects.However,the mechanistic link of cilia to CMD complications is still poorly understood.Herein,we describe significant cilium disassembly upon treatment of cells with pathologically relevant aldoses rather than the corresponding sugar alcohols.Moreover,environmental aldehydes are able to trigger cilium disassembly by the steric hindrance effect of their formyl groups.Mechanistic studies reveal that aldehydes stimulate extracellular calcium influx across the plasma membrane,which subsequently activates the calmodulin-Aurora A-histone deacetylase 6 pathway to deacetylate axonemal microtubules and triggers cilium disassembly.In vivo experiments further show that Hdac6 knockout mice are resistant to aldehyde-induced disassembly of tracheal cilia and sperm flagella.These findings reveal a previously unrecognized role for formyl group-mediated cilium disassembly in the complications of CMDs.展开更多
Low-rank tensor completion(LRTC)restores missing elements in multidimensional visual data;the challenge is representing the inherent structures within this data.Typical methods either suffer from inefficiency owing to...Low-rank tensor completion(LRTC)restores missing elements in multidimensional visual data;the challenge is representing the inherent structures within this data.Typical methods either suffer from inefficiency owing to the combination of multiple regularizers or perform suboptimally using inappropriate priors.In this study,we further investigated LRTC using tensor singular value decomposition(t-SVD).Inspired by the tensor-tensor product(t-product),we proposed a unified transformed t-SVD method that employs an invertible linear transform with a unitary transform matrix.However,the t-SVD-based framework lacks the flexibility necessary to represent different inherent relations along the tensor modes.To address this issue,we propose a tensor represented by a series of multidimensional unfolding tensors to fully explore the hidden structure of the original data.Furthermore,the proposed model can be solved efficiently using the alternate-direction method of the multiplier(ADMM)approach.Extensive experimental results on multidimensional visual data(multispectral images,hyperspectral images,and videos)demonstrated the superiority of the proposed method over other state-of-the-art LRTC-related methods.展开更多
Dear Editor,O-GIcNAcylation is a nutrient sensor that is particularly sensitive to environmental glucose(Hardiville and Hart,2014).Glucose can be converted to UDP-GIcNAc through the hexosamine biosynthetic pathway,pro...Dear Editor,O-GIcNAcylation is a nutrient sensor that is particularly sensitive to environmental glucose(Hardiville and Hart,2014).Glucose can be converted to UDP-GIcNAc through the hexosamine biosynthetic pathway,providing a substrate for O-GIcNAcylation.Two enzymes participate in this reversible modification,O-GIcNAc transferase(OGT),which adds a single GIcNAc residue to the serine/threonine sites of proteins,and O-GIcNAcase(OGA),which removes the residue(Yang and Qian,2017).展开更多
The repair joints of high-voltage cables play a significant role in the urgent cable main-tenance,by recovering cable conductor,insulation,shielding layer and waterproof layer especially for submarine cables.However,t...The repair joints of high-voltage cables play a significant role in the urgent cable main-tenance,by recovering cable conductor,insulation,shielding layer and waterproof layer especially for submarine cables.However,the molecule diffusion and permeation pro-cesses from waterproof sealant into the cable joint insulation occur,leading to the insulation ageing and deterioration.In this article,the molecule diffusion behaviours of six typical molecules from the asphalt-based and polyurethane-based waterproof sealants into silicone rubber insulation are investigated.The results show that the order of diffusion coefficients is as follows,phenanthrene>fluoranthene>pyrene>benzo[k]fluoranthene>indeno[1,2,3-cd]pyrene>polyurethane(PU).The relative molecular mass and binding energy are pivotal factors affecting the diffusion behaviour,while there is a linear relationship between the logarithm of the diffusion coefficient and the ratio of binding energy to relative molecular mass.Besides,the rising ambient temperature in-creases the fraction of free volume of silicone rubber and decreases the binding energy,thus resulting in a higher diffusion coefficient and an enhanced permeation process of the asphalt-based sealant.In summary,the PU-based waterproof sealant,with a much lower permeability than the asphalt-based material,has a potential application in the waterproof layer for high-voltage submarine cable repair joints.展开更多
During the overall processing of thin-walled parts(TWPs),the guaranteed capability of the machining process and quality is determined by fixtures.Therefore,reliable fixtures suitable for the structure and machining pr...During the overall processing of thin-walled parts(TWPs),the guaranteed capability of the machining process and quality is determined by fixtures.Therefore,reliable fixtures suitable for the structure and machining process of TWP are essential.In this review,the key role of fixtures in the manufacturing system is initially discussed.The main problems in machining and workholding due to the characteristics of TWP are then analyzed in detail.Afterward,the definition of TWP fixtures is reinterpreted from narrow and broad perspectives.Fixture functions corresponding to the issues of machining and workholding are then clearly stated.Fixture categories are classified systematically according to previous research achievements,and the operation mode,functional characteristics,and structure of each fixture are comprehensively described.The function and execution mode of TWP fixtures are then systematically summarized and analyzed,and the functions of various TWP fixtures are evaluated.Some directions for future research on TWP fixtures technology are also proposed.The main purpose of this review is to provide some reference and guidance for scholars to examine TWP fixtures.展开更多
Endothelial cilia are microtubule-based hair-like protrusions in the lumen of blood vessels that function as fluid mechanosensors to regulate vascular hemodynamics. However, the functions of endothelial cilia in vascu...Endothelial cilia are microtubule-based hair-like protrusions in the lumen of blood vessels that function as fluid mechanosensors to regulate vascular hemodynamics. However, the functions of endothelial cilia in vascular development remain controversial. In this study, depletion of several key proteins responsible for ciliogenesis allows us to identify a cilium-independent role for intraflagellar transport 88(IFT88) in mammalian angiogenesis. Disruption of primary cilia by heat shock does not affect the angiogenic process. However, depletion of IFT88 significantly inhibits angiogenesis both in vitro and in vivo. IFT88 mediates angiogenesis by regulating the migration, polarization, proliferation, and oriented division of vascular endothelial cells. Further mechanistic studies demonstrate that IFT88 interacts with c-tubulin and microtubule plus-end tracking proteins and promotes microtubule stability. Our findings indicate that IFT88 regulates angiogenesis through its actions in microtubule-based cellular processes, independent of its role in ciliogenesis.展开更多
In this paper, we study the large time behaviour of the solution of the Fokker-Planck equation with general potential. For the long range potential, we prove the polynomial decay estimate in time of the solution. For ...In this paper, we study the large time behaviour of the solution of the Fokker-Planck equation with general potential. For the long range potential, we prove the polynomial decay estimate in time of the solution. For the slowly growing potential, we prove the sub-exponential convergence of the solution toward the equilibrium.展开更多
由于云的时空尺度非常宽广,云微物理参数化方案一直是气候模式中的薄弱环节.本文借鉴中尺度模式云微物理方案从双参数向三参数扩展的思路方法,发展了联合地球系统模式(Community Integrated Earth System Model,CIESM)三参数冰相云微物...由于云的时空尺度非常宽广,云微物理参数化方案一直是气候模式中的薄弱环节.本文借鉴中尺度模式云微物理方案从双参数向三参数扩展的思路方法,发展了联合地球系统模式(Community Integrated Earth System Model,CIESM)三参数冰相云微物理方案,弥补了默认双参数方案不能预报冰晶粒径分布谱形参数(μ)的不足,进而分析了双、三参数方案对气候模拟的影响.模拟结果表明,相较于双参数方案(μ为0),三参数方案预报得出的μ更为合理,其在垂直分布上整体呈现出“高层小低层大”的特点,高层的低值主要是由于冰晶核化以及较大的冰晶粒子沉降后粒子之间相互混合导致的,而低层的高值主要是由于冰晶粒子在沉降过程中的粒子分选机制导致的.与双、三参数方案中μ的差异相呼应,模式模拟的气候平均态出现明显差异,其中三参数方案模拟的总云云量、低云云量、中云云量和总降水相较于双参数方案更接近观测结果,高云云量的误差增大.其中总降水的改进主要是由于高云云量的增加,大气稳定度增加,对流性降水减少.此外,还调整了相关参数,以改善模式对辐射的模拟能力.总之,本文在全球气候模式中评估了双、三参数方案对于模拟气候平均态的不同影响,为气候模式中云微物理方案的发展改进提供了一定的参考意义.展开更多
Continuum robots,which are characterized by high length-to-diameter ratios and flexible structures,show great potential for various applications in confined and irregular environments.Due to the combination of motion ...Continuum robots,which are characterized by high length-to-diameter ratios and flexible structures,show great potential for various applications in confined and irregular environments.Due to the combination of motion modes,the existence of multiple solutions,and the presence of complex obstacle constraints,motion planning for these robots is highly challenging.To tackle the challenges of online and flexible operation for continuum robots,we propose a flexible head-following motion planning method that is suitable for scalable and bendable continuum robots.Firstly,we establish a piecewise constant curvature(PCC)kinematic model for scalable and bendable continuum robots.The article proposes an adaptive auxiliary points model and a method for updating key nodes in head-following motion to enhance the precise tracking capability for paths with different curvatures.Additionally,the article integrates the strategy for adjusting the posture of local joints of the robot into the head-following motion planning method,which is beneficial for achieving safe obstacle avoidance in local areas.The article concludes by presenting the results of multiple sets of motion simulation experiments and prototype experiments.The study demonstrates that the algorithm presented in this paper effectively navigates and adjusts posture to avoid obstacles,meeting the real-time demands of online operations.The average time for a single-step solution is 4.41×10^(-5) s,and the average tracking accuracy forcircular paths is 7.8928mm.展开更多
基金supported in part by the National Nat-ural Science Foundation of China(52177110)Key Pro-gram of the National Natural Science Foundation of China(U22B20106,U2142206)+2 种基金Shenzhen Science and Technology Program(JCYJ20210324131409026)the Science and Technology Project of the State Grid Corpo-ration of China(5200-202319382A-2-3-XG)State Grid Zhejiang Elctric Power Co.,Ltd.Science and Tech-nology Project(B311DS24001A).
文摘Typhoons can cause large-area blackouts or partial outages of distribution networks.We define a partial outage state in the distribution network as a gray state and propose a gray-start strategy and two-stage distribution network emergency recovery framework.A phase-space reconstruction and stacked integrated model for predicting wind and photovoltaic generation during typhoon disasters is proposed in the first stage.This provides guidance for second-stage post-disaster emergency recovery scheduling.The emergency recovery scheduling model is established in the second stage,and this model is supported by a thermal power-generating unit,mobile emergency generators,and distributed generators.Distributed generation includes wind power generation,photovoltaics,fuel cells,etc.Simultaneously,we con-sider the gray-start based on the pumped storage unit to be an important first step in the emergency recovery strategy.This model is val-idated on the improved IEEE 33 node system,which utilizes data from the 2022 super typhoon“Muifa”in Zhoushan,Zhejiang,China.Simulations indicate the superiority of a gray start with a pumped storage unit and the proposed emergency recovery strategy.
基金partly supported by National Natural Science Foundation of China(No.51577098)the State Grid Corporation of China,and China Southern Power Grid
文摘Different types of lightning air terminals have been designed over the years.Concern regarding the effect of different types of air terminals,especially the early streamer emission(ESE)-type,remains controversial.This paper describes the discharge characteristics of different types of air terminals,two of which are quite similar to the ESE-type dynasphere,and concludes that the tested non-standard air terminals have discharge characteristics similar to those of Franklin rods and that their lightning protection performance should be similar.
基金supported by grants from the National Natural Science Foundation of China(31991193 and 32230025)the National Key R&D Program of China(2021YFA1101001).
文摘Carbohydrate metabolism disorders(CMDs),such as diabetes,galactosemia,and mannosidosis,cause ciliopathy-like multiorgan defects.However,the mechanistic link of cilia to CMD complications is still poorly understood.Herein,we describe significant cilium disassembly upon treatment of cells with pathologically relevant aldoses rather than the corresponding sugar alcohols.Moreover,environmental aldehydes are able to trigger cilium disassembly by the steric hindrance effect of their formyl groups.Mechanistic studies reveal that aldehydes stimulate extracellular calcium influx across the plasma membrane,which subsequently activates the calmodulin-Aurora A-histone deacetylase 6 pathway to deacetylate axonemal microtubules and triggers cilium disassembly.In vivo experiments further show that Hdac6 knockout mice are resistant to aldehyde-induced disassembly of tracheal cilia and sperm flagella.These findings reveal a previously unrecognized role for formyl group-mediated cilium disassembly in the complications of CMDs.
基金supported by the Zhejiang Lab Key Research Project(No.G2021NB0AL03)Zhejiang Lab Youth Foundation Project(No.K2023NB0AA03).
文摘Low-rank tensor completion(LRTC)restores missing elements in multidimensional visual data;the challenge is representing the inherent structures within this data.Typical methods either suffer from inefficiency owing to the combination of multiple regularizers or perform suboptimally using inappropriate priors.In this study,we further investigated LRTC using tensor singular value decomposition(t-SVD).Inspired by the tensor-tensor product(t-product),we proposed a unified transformed t-SVD method that employs an invertible linear transform with a unitary transform matrix.However,the t-SVD-based framework lacks the flexibility necessary to represent different inherent relations along the tensor modes.To address this issue,we propose a tensor represented by a series of multidimensional unfolding tensors to fully explore the hidden structure of the original data.Furthermore,the proposed model can be solved efficiently using the alternate-direction method of the multiplier(ADMM)approach.Extensive experimental results on multidimensional visual data(multispectral images,hyperspectral images,and videos)demonstrated the superiority of the proposed method over other state-of-the-art LRTC-related methods.
基金We thank Dr.Wen Ning for providing the Ube-Cre-ERT2 mice.This work was supported by grants from the National Key R&D Program of China(2017YFA0503502)the National Natural Science Foundation of China(31991193).Fan Yu,Te Li。Yanchao Sui,Qingxia Chen,Song Yang,Jia Yang,Renjie Hong,Dengwen they have no conflict of interest.All institutional and national guidelines for the care and use of laboratory animals were fllowed.Li,Xiumin Yan,Wei Zhao,Xueliang Zhu,and Jun Zhou declare that。
文摘Dear Editor,O-GIcNAcylation is a nutrient sensor that is particularly sensitive to environmental glucose(Hardiville and Hart,2014).Glucose can be converted to UDP-GIcNAc through the hexosamine biosynthetic pathway,providing a substrate for O-GIcNAcylation.Two enzymes participate in this reversible modification,O-GIcNAc transferase(OGT),which adds a single GIcNAc residue to the serine/threonine sites of proteins,and O-GIcNAcase(OGA),which removes the residue(Yang and Qian,2017).
基金National Natural Science Foundation of China,Grant/Award Number:51707133National Key Research and Development Program of China,Grant/Award Number:2016YFB0900701。
文摘The repair joints of high-voltage cables play a significant role in the urgent cable main-tenance,by recovering cable conductor,insulation,shielding layer and waterproof layer especially for submarine cables.However,the molecule diffusion and permeation pro-cesses from waterproof sealant into the cable joint insulation occur,leading to the insulation ageing and deterioration.In this article,the molecule diffusion behaviours of six typical molecules from the asphalt-based and polyurethane-based waterproof sealants into silicone rubber insulation are investigated.The results show that the order of diffusion coefficients is as follows,phenanthrene>fluoranthene>pyrene>benzo[k]fluoranthene>indeno[1,2,3-cd]pyrene>polyurethane(PU).The relative molecular mass and binding energy are pivotal factors affecting the diffusion behaviour,while there is a linear relationship between the logarithm of the diffusion coefficient and the ratio of binding energy to relative molecular mass.Besides,the rising ambient temperature in-creases the fraction of free volume of silicone rubber and decreases the binding energy,thus resulting in a higher diffusion coefficient and an enhanced permeation process of the asphalt-based sealant.In summary,the PU-based waterproof sealant,with a much lower permeability than the asphalt-based material,has a potential application in the waterproof layer for high-voltage submarine cable repair joints.
基金support from the National Natural Science Foundation of China(Grant Nos.U20B2033,51975093)the Natural Science Foundation of Liaoning,China(Grant No.2020-YQ-09)。
文摘During the overall processing of thin-walled parts(TWPs),the guaranteed capability of the machining process and quality is determined by fixtures.Therefore,reliable fixtures suitable for the structure and machining process of TWP are essential.In this review,the key role of fixtures in the manufacturing system is initially discussed.The main problems in machining and workholding due to the characteristics of TWP are then analyzed in detail.Afterward,the definition of TWP fixtures is reinterpreted from narrow and broad perspectives.Fixture functions corresponding to the issues of machining and workholding are then clearly stated.Fixture categories are classified systematically according to previous research achievements,and the operation mode,functional characteristics,and structure of each fixture are comprehensively described.The function and execution mode of TWP fixtures are then systematically summarized and analyzed,and the functions of various TWP fixtures are evaluated.Some directions for future research on TWP fixtures technology are also proposed.The main purpose of this review is to provide some reference and guidance for scholars to examine TWP fixtures.
基金supported by grants from the National Key R&D Program of China(2017YFA0503502)the National Natural Science Foundation of China(31730050,31871347,and 31900502)。
文摘Endothelial cilia are microtubule-based hair-like protrusions in the lumen of blood vessels that function as fluid mechanosensors to regulate vascular hemodynamics. However, the functions of endothelial cilia in vascular development remain controversial. In this study, depletion of several key proteins responsible for ciliogenesis allows us to identify a cilium-independent role for intraflagellar transport 88(IFT88) in mammalian angiogenesis. Disruption of primary cilia by heat shock does not affect the angiogenic process. However, depletion of IFT88 significantly inhibits angiogenesis both in vitro and in vivo. IFT88 mediates angiogenesis by regulating the migration, polarization, proliferation, and oriented division of vascular endothelial cells. Further mechanistic studies demonstrate that IFT88 interacts with c-tubulin and microtubule plus-end tracking proteins and promotes microtubule stability. Our findings indicate that IFT88 regulates angiogenesis through its actions in microtubule-based cellular processes, independent of its role in ciliogenesis.
基金supported by National Natural Science Foundation of China(Grant No.11421101)
文摘In this paper, we study the large time behaviour of the solution of the Fokker-Planck equation with general potential. For the long range potential, we prove the polynomial decay estimate in time of the solution. For the slowly growing potential, we prove the sub-exponential convergence of the solution toward the equilibrium.
文摘由于云的时空尺度非常宽广,云微物理参数化方案一直是气候模式中的薄弱环节.本文借鉴中尺度模式云微物理方案从双参数向三参数扩展的思路方法,发展了联合地球系统模式(Community Integrated Earth System Model,CIESM)三参数冰相云微物理方案,弥补了默认双参数方案不能预报冰晶粒径分布谱形参数(μ)的不足,进而分析了双、三参数方案对气候模拟的影响.模拟结果表明,相较于双参数方案(μ为0),三参数方案预报得出的μ更为合理,其在垂直分布上整体呈现出“高层小低层大”的特点,高层的低值主要是由于冰晶核化以及较大的冰晶粒子沉降后粒子之间相互混合导致的,而低层的高值主要是由于冰晶粒子在沉降过程中的粒子分选机制导致的.与双、三参数方案中μ的差异相呼应,模式模拟的气候平均态出现明显差异,其中三参数方案模拟的总云云量、低云云量、中云云量和总降水相较于双参数方案更接近观测结果,高云云量的误差增大.其中总降水的改进主要是由于高云云量的增加,大气稳定度增加,对流性降水减少.此外,还调整了相关参数,以改善模式对辐射的模拟能力.总之,本文在全球气候模式中评估了双、三参数方案对于模拟气候平均态的不同影响,为气候模式中云微物理方案的发展改进提供了一定的参考意义.
基金supported in part by the Fundamental Research Funds for the Central Universities,China(DUT22GF301).
文摘Continuum robots,which are characterized by high length-to-diameter ratios and flexible structures,show great potential for various applications in confined and irregular environments.Due to the combination of motion modes,the existence of multiple solutions,and the presence of complex obstacle constraints,motion planning for these robots is highly challenging.To tackle the challenges of online and flexible operation for continuum robots,we propose a flexible head-following motion planning method that is suitable for scalable and bendable continuum robots.Firstly,we establish a piecewise constant curvature(PCC)kinematic model for scalable and bendable continuum robots.The article proposes an adaptive auxiliary points model and a method for updating key nodes in head-following motion to enhance the precise tracking capability for paths with different curvatures.Additionally,the article integrates the strategy for adjusting the posture of local joints of the robot into the head-following motion planning method,which is beneficial for achieving safe obstacle avoidance in local areas.The article concludes by presenting the results of multiple sets of motion simulation experiments and prototype experiments.The study demonstrates that the algorithm presented in this paper effectively navigates and adjusts posture to avoid obstacles,meeting the real-time demands of online operations.The average time for a single-step solution is 4.41×10^(-5) s,and the average tracking accuracy forcircular paths is 7.8928mm.
