The monument thermal effect(MTE)displacements could result in periodical signals with several mil-limeters magnitudes in the vertical and horizontal GPS position time series.However,the interaction ofvarious origins o...The monument thermal effect(MTE)displacements could result in periodical signals with several mil-limeters magnitudes in the vertical and horizontal GPS position time series.However,the interaction ofvarious origins of periodic signals in GPS observations makes it difficult to isolate the millimeter-levelMTE displacement from other signals and noises.In this study,to assess the diurnal and semidiurnalsignals induced by MTE,we processed 12 very short GPS baselines(VSGB)with length<150 m.Themonument pairs for each baseline differ in their heights,horizontal structure,or base foundations.Meanwhile,two zero-baselines were also processed as the control group.Results showed that the sea-sonal signals observed in VSGB time series in the horizontal and vertical directions,were mainly inducedby seasonal MTE.Time-varying diurnal and semidiurnal signals with amplitude up to 4 mm wereobserved in the vertical direction for baselines with monument height difference(MHD)larger than10 m.Horizontal diurnal signal with an amplitude of about 2 mm was also detected for baselines withnon-axisymmetric monument structure.The orientation of the detected horizontal displacement wascoherent with the direction of daily temperature variation(DTV)driven by direct solar radiation,whichindicates that the diurnal and semidiurnal signals are likely induced by MTE.The observed high-frequency MTE displacements,if not well modeled and removed,may propagate into spurious long-term signals and bias the velocity estimation in the daily GPS time series.展开更多
The drifting baselines of capillary electrophoresis affect the veracity of analysis greatly. This paper presents Threshold Fitting Technique(TFT) so as to subtract the baselines from the original signals and emendate ...The drifting baselines of capillary electrophoresis affect the veracity of analysis greatly. This paper presents Threshold Fitting Technique(TFT) so as to subtract the baselines from the original signals and emendate the signals. In TFT, wavelet and curve fitting technique are applied synthetically, thresholds are decided by the computer automatically. Many experiments of signal processing indicate that TFT is simple for being used, there are few man-induced factors, and the results are satisfactory. TFT can be applied for noisy signals without any pre-processing.展开更多
In the case of a medium-long baseline, for real-time kinematic (RTK) positioning, the fixed rate of integer ambiguity is low due to the distance between the base station and the observation station. Moreover, the atmo...In the case of a medium-long baseline, for real-time kinematic (RTK) positioning, the fixed rate of integer ambiguity is low due to the distance between the base station and the observation station. Moreover, the atmospheric delay after differential processing cannot be ignored. For correcting the residual atmospheric errors, we proposed a GPS/BDS/Galileo/GLONASS four-system fusion RTK positioning algorithm, which is based on the extended Kalman filter (EKF) algorithm. After realizing the spatio-temporal unification of multiple global navigation satellite systems (GNSSs), we introduced a parameter estimation of atmospheric errors based on the EKF model, using the least-squares integer ambiguity decorrelation adjustment (LAMBDA) to calculate the integer ambiguity. After conducting experiments for different baselines, the proposed RTK positioning algorithm can achieve centimeter-level positioning accuracy in the case of medium-long baselines. In addition, the time required to solve the fixed solution is shorter than that of the traditional RTK positioning algorithm.展开更多
Methane(CH4)is a very potent greenhouse gas with a globalwarming potential of approximately 80 times that of carbon dioxide(CO_(2))on a decadal scale[1].By November 2024,159 countrieshave signed the Global Methane Ple...Methane(CH4)is a very potent greenhouse gas with a globalwarming potential of approximately 80 times that of carbon dioxide(CO_(2))on a decadal scale[1].By November 2024,159 countrieshave signed the Global Methane Pledge,committing to reduceanthropogenic emissions by at least 30%by 2030 relative to the 2020 level(https://www.globalmethanepledge.org).In November2023,the Chinese government released an action plan dedicatedto methane emission control,including specific targets in differentsource sectors(https://www.mee.gov.cn/).However,large discrepancies still exist in China’s current methane inventories,hinderingthe setting of mitigation goals.By now,the national anthropogenicmethane emission estimates still vary by at least 30%,and sectoralemission estimates may differ by a factor of 2–5(Fig.1).To supportChina’s methane emission control plan,a key priority is to determine the emission baselines,which this work aims to address.展开更多
To explore emission baseline, technically the most difficult issue for Clean Development Mechanism (CDM) project development, as well as to examine whether CDM is a possible way to help Beijing restructure its heating...To explore emission baseline, technically the most difficult issue for Clean Development Mechanism (CDM) project development, as well as to examine whether CDM is a possible way to help Beijing restructure its heating energy consumption, this paper conducts a CDM baseline case study on residential heating in Beijing. Based on investigation, energy consumption forecast and economic analysis of future technology options, the technology benchmark and site specific baselines for both retrofit projects and new heating projects have been discussed. The results indicate that fuel switching from coal to natural gas can meet the additionality criteria in many cases and will be the main type of CDM project. In addition, it also proves that the technology benchmark and the case by case baseline setting approach are applicable for future CDM cooperation projects on heating in Beijing.展开更多
Basic communication standards that we rely upon reduce friction for consumers,customers and businesses,speed innovation and allow for cross-border collaboration among companies.That is critical for establishing global...Basic communication standards that we rely upon reduce friction for consumers,customers and businesses,speed innovation and allow for cross-border collaboration among companies.That is critical for establishing global baselines of trust.What standards can do that politics cannot is to bring people together,encourage collaboration,and encourage trusting relationships and the ability to share and develop interoperable communication systems.Today we are building roads that lead to quantum technologies,artificial intelligence and blockchain technologies,but the rules of those roads are yet to be written.The industry has an important role to play in developing rules of the road.Those rules need to start with a very basic foundation,such as data identification secured by design standards,standards for privacy protection,and watermarking,tracing and accountability of AI technologies and algorithms.These are all very achievable objectives,and they form together a foundation of trust that customers and governments worldwide can rely upon.展开更多
The rice stem borer,Chilo suppressalis(Walker)(Lepidoptera:Crambidae),is one of the most serious pests in rice-growing areas,and it has developed resistance to most insecticides currently used in the field.Cyproflanil...The rice stem borer,Chilo suppressalis(Walker)(Lepidoptera:Crambidae),is one of the most serious pests in rice-growing areas,and it has developed resistance to most insecticides currently used in the field.Cyproflanilide is a novel meta-diamide insecticide that has shown high activities to multiple pests.Evaluating the risk of resistance to cyproflanilide in C.suppressalis is necessary for its preventive resistance management.Here we established the baseline susceptibility of C.suppressalis to cyproflanilide by the rice-seedling dipping method and topical application,and the LC_(50) and LD_(50) values were 0.026 mg L^(-1) and 0.122 ng/larva,respectively.The LC_(50) values of cyproflanilide in 37 field populations ranged from 0.012 to 0.061 mg L^(-1),and 25 field populations exhibited resistance to chlorantraniliprole with the highest LC_(50) value of 3,770.059 mg L^(-1).In addition,a logistic distribution model analysis indicated that only 0.048 mg L^(-1) of cyproflanilide was required to kill 90% field chlorantraniliprole-resistant populations of C.suppressalis,compared to 2,087.764 mg L^(-1) of chlorantraniliprole for a similar level of control.Resistance screening over 19 generations did not result in resistance to cyproflanilide(RR=3.1-fold).The realized heritability(h^(2))of resistance was estimated as 0.067 by using threshold trait analysis,suggesting a low risk of cyproflanilide resistance development in susceptible strains.The Cypro-SEL population(F_(10))had no obvious fitness cost(relative fitness=0.96),and no significant changes in sensitivity to seven tested insecticides.These findings suggested that cyproflanilide is a promising insecticide for the management of chlorantraniliprole-resistant C.suppressalis.Moreover,this integrated risk assessment provides scientific application guidelines for the sustainable resistance management of cyproflanilide for controlling C.suppressalis.展开更多
This paper delves into the baseline design under the baseline parameterization model in experimental design, focusing on the relationship between the K-aberration criterion and the word length pattern (WLP) of regular...This paper delves into the baseline design under the baseline parameterization model in experimental design, focusing on the relationship between the K-aberration criterion and the word length pattern (WLP) of regular two-level designs. The paper provides a detailed analysis of the relationship between K5and the WLP for regular two-level designs with resolution t=3, and proposes corresponding theoretical results. These results not only theoretically reveal the connection between the orthogonal parameterization model and the baseline parameterization model but also provide theoretical support for finding the K-aberration optimal regular two-level baseline designs. It demonstrates how to apply these theories to evaluate and select the optimal experimental designs. In practical applications, experimental designers can utilize the theoretical results of this paper to quickly assess and select regular two-level baseline designs with minimal K-aberration by analyzing the WLP of the experimental design. This allows for the identification of key factors that significantly affect the experimental outcomes without frequently changing the factor levels, thereby maximizing the benefits of the experiment.展开更多
Extreme disturbance activity is a signature of anthropogenic environmental change. Empirical information describing the historical normative limits of disturbance regimes provides baseline data that facilitates the de...Extreme disturbance activity is a signature of anthropogenic environmental change. Empirical information describing the historical normative limits of disturbance regimes provides baseline data that facilitates the detection of contemporary trends in both disturbances and community-level responses. Quantifying the attributes of historical disturbances is challenging due to their transient episodic nature, with decades-to centurieslong intervals between recurrences. Unmanaged primary forests that support centuries-old trees therefore serve as unique reference systems for quantifying past disturbance regimes. We surveyed relict stands of primary beech-dominated forests over wide environmental gradients in the Carpathian Mountains of Europe. We collected core samples from 3,026 trees in 208 field survey plots distributed across 13 forest stands in two countries. We used dendrochronological methods to analyze time-series of annually-resolved ring-width variation and to identify anomalous growth patterns diagnostic of past forest canopy removal. A 180-year record(1810–1990) of spatially and temporally explicit disturbance events(n =333) was compiled and used to derive s tatistical attributes of the disturbance regime. We quantified disturbance severity(canopy area lost), patch size, and return intervals. Our analyses describe a complex regime where a background of relatively frequent, smallscale, low-to intermediate-severity disturbance was punctuated by episodic large-scale high-severity events. Even the most severe events were non-catastrophic at a stand level, leaving significant residual tree cover that supported a continuity of ecological function. We did not detect evidence for an expected climate-induced intensification of disturbance with time, but methodological limitations precluded an assessment of disturbance activity in the decades since 1990.展开更多
Toroidal torques,generated by the resonant magnetic perturbation(RMP)and acting on the plasma column,are numerically systematically investigated for an ITER baseline scenario.The neoclassical toroidal viscosity(NTV),i...Toroidal torques,generated by the resonant magnetic perturbation(RMP)and acting on the plasma column,are numerically systematically investigated for an ITER baseline scenario.The neoclassical toroidal viscosity(NTV),in particular the resonant portion,is found to provide the dominant contribution to the total toroidal torque under the slow plasma flow regime in ITER.While the electromagnetic torque always opposes the plasma flow,the toroidal torque associated with the Reynolds stress enhances the plasma flow independent of the flow direction.A peculiar double-peak structure for the net NTV torque is robustly computed for ITER,as the toroidal rotation frequency is scanned near the zero value.This structure is found to be ultimately due to a non-monotonic behavior of the wave-particle resonance integral(over the particle pitch angle)in the superbanana plateau NTV regime in ITER.These findings are qualitatively insensitive to variations of a range of factors including the wall resistivity,the plasma pedestal flow and the assumed frequency of the rotating RMP field.展开更多
The intertidal zone of mangroves has a significant impact on the ecological environment by serving as a crucial habitat for a wide range of organisms.When assessing heavy metal contamination in sediments within this z...The intertidal zone of mangroves has a significant impact on the ecological environment by serving as a crucial habitat for a wide range of organisms.When assessing heavy metal contamination in sediments within this zone,it is essential to establish a regional geochemical baseline that accounts for natural variations.In this study,regional geochemical baselines of heavy metals were established based on core sediment samples collected from Dongzhai Harbor in November 2015.Linear regression analysis was employed to examine the correlations between heavy metals and potential normalized elements.Subsequently,the sediment quality and intensity of pollutant input in the sediments of a mangrove intertidal zone were evaluated with enrichment factor(EF)and excessive influx of heavy metals.The EF values for Cr,Cd,Pb,Zn,and Ni in the study area were all below 1.5,indicating minimal levels of contamination;however,minor Cu contamination was observed in the high tidal flat area due to potential terrestrial inputs.These findings suggest that the overall environmental quality about heavy metals was good within the intertidal zone of mangroves.Moreover,as for the excess fluxes of heavy metals in intertidal sediments,there was consistency between influence and intervention of human activities on sedimentary environment during the selected period when examining variation trends.展开更多
Sea topography information holds significant importance in oceanic research and the climate change detection.Radar imaging altimetry has emerged as the leading approach for global ocean observation,employing synthetic...Sea topography information holds significant importance in oceanic research and the climate change detection.Radar imaging altimetry has emerged as the leading approach for global ocean observation,employing synthetic aperture radar(SAR)interferometry to enhance the spatial resolution of Sea topography.Nevertheless,current payload capacity and satellite hardware limitations prevent the extension of the interferometric baseline by enlarging the physical antenna size.This constraint hinders achieving centimeter-level accuracy in interferometric altimetry.To address this challenge,we conducted a numerical simulation to assess the viability of a large baseline interferometric imaging altimeter(LB-IIA).By controlling the baseline within the range of 600-1000 m through spiral orbit design in two satellites and mitigating baseline de-correlation with the carrier frequency shift(CFS)technique,we aimed to overcome the above limitations.Our findings demonstrate the efficacy of the CFS technique in compensating for baseline decoherence,elevating coherence from less than 0.1 to over 0.85.Concurrently.The height difference accuracy between neighboring sea surfaces reaches 1 cm within a 1 km resolution.This study is anticipated to serve as a foundational reference for future interferometric imaging altimeter development,catering to the demand for high-precision sea topography data in accurate global bathymetry inversion.展开更多
The natural visibility graph method has been widely used in physiological signal analysis,but it fails to accurately handle signals with data points below the baseline.Such signals are common across various physiologi...The natural visibility graph method has been widely used in physiological signal analysis,but it fails to accurately handle signals with data points below the baseline.Such signals are common across various physiological measurements,including electroencephalograph(EEG)and functional magnetic resonance imaging(fMRI),and are crucial for insights into physiological phenomena.This study introduces a novel method,the baseline perspective visibility graph(BPVG),which can analyze time series by accurately capturing connectivity across data points both above and below the baseline.We present the BPVG construction process and validate its performance using simulated signals.Results demonstrate that BPVG accurately translates periodic,random,and fractal signals into regular,random,and scale-free networks respectively,exhibiting diverse degree distribution traits.Furthermore,we apply BPVG to classify Alzheimer’s disease(AD)patients from healthy controls using EEG data and identify non-demented adults at varying dementia risk using resting-state fMRI(rs-fMRI)data.Utilizing degree distribution entropy derived from BPVG networks,our results exceed the best accuracy benchmark(77.01%)in EEG analysis,especially at channels F4(78.46%)and O1(81.54%).Additionally,our rs-fMRI analysis achieves a statistically significant classification accuracy of 76.74%.These findings highlight the effectiveness of BPVG in distinguishing various time series types and its practical utility in EEG and rs-fMRI analysis for early AD detection and dementia risk assessment.In conclusion,BPVG’s validation across both simulated and real data confirms its capability to capture comprehensive information from time series,irrespective of baseline constraints,providing a novel method for studying neural physiological signals.展开更多
Based on the finite element (FE) program ANSYS, a three-dimensional model for the Runyang Suspension Bridge (RSB) is established. The structural natural frequency, vibration mode, stress and displacement response ...Based on the finite element (FE) program ANSYS, a three-dimensional model for the Runyang Suspension Bridge (RSB) is established. The structural natural frequency, vibration mode, stress and displacement response under various load cases are given. A new method of FE model updating is presented based on the physical meaning of sensitivity and the penalty function concept. In this method, the structural model is updated by modifying the parameters of design, and validated by structural natural vibration characteristics, stress response as well as displacement response. The design parameters used for updating are bounded according to measured static response and engineering judgment. The FE model of RSB is updated and validated by the measurements coming from the structural health monitoring system (SHMS), and the FE baseline model reflecting the current state of RSB is achieved. Both the dynamic and static results show that the method is effective in updating the FE model of long span suspension bridges. The results obtained provide an important research basis for damage alarming and health monitoring of the RSB.展开更多
The authors proposed a moving long baseline algorithm based on the extended Kalman filter (EKF) for cooperative navigation and localization of multi-unmanned underwater vehicles (UUVs). Research on cooperative nav...The authors proposed a moving long baseline algorithm based on the extended Kalman filter (EKF) for cooperative navigation and localization of multi-unmanned underwater vehicles (UUVs). Research on cooperative navigation and localization for multi-UUVs is important to solve navigation problems that restrict long and deep excursions. The authors investigated improvements in navigation accuracy. In the moving long base line (MLBL) structure, the master UUV is equipped with a high precision navigation system as a node of the moving long baseline, and the slave UUV is equipped with a low precision navigation system. They are both equipped with acoustic devices to measure relative location. Using traditional triangulation methods to calculate the position of the slave UUV may cause a faulty solution. An EKF was designed to solve this, combining the proprioceptive and exteroceptive sensors. Research results proved that the navigational accuracy is improved significantly with the MLBL method based on EKF.展开更多
[Objective] This study aimed to avoid and delay the generation of resis- tance in Botrytis cinerea to boscalid. [Method] The sensitivity of Botrytis cinerea to boscalid was tested by the mycelial growth rate method. T...[Objective] This study aimed to avoid and delay the generation of resis- tance in Botrytis cinerea to boscalid. [Method] The sensitivity of Botrytis cinerea to boscalid was tested by the mycelial growth rate method. The distribution of sensitivity variation of B. cinerea to boscalid in different regions was cleared, and the sen- sitivity baseline of B. cinerea from Liaoning Province to boscalid was established. [Result] The ECso values of B. cinerea strains from Liaoning Province ranged from 0.080 0 to 7.787 2μg/ml, and the highest ECho value was 97.34 times higher than the minimum. The average EC50 value (1.973μg/ml) of the 158 strains was treated as the baseline sensitivity of B. cinerea from Liaoning Province to boscalid. [Conclu- sion] It is essential to conduct a risk assessment of drug resistance in B. cinerea to boscalid.展开更多
基金funded by the Independent Innovation Project of Changjiang Institute of Survey,Planning,Design and Research Corporation (CX2020Z32)supported by the National Natural Science Foundation of China (Grant Numbers42204006 and 42104028)the Open Fund of Hubei Luojia Laboratory (Grant Numbers 230100020 and 230100019)
文摘The monument thermal effect(MTE)displacements could result in periodical signals with several mil-limeters magnitudes in the vertical and horizontal GPS position time series.However,the interaction ofvarious origins of periodic signals in GPS observations makes it difficult to isolate the millimeter-levelMTE displacement from other signals and noises.In this study,to assess the diurnal and semidiurnalsignals induced by MTE,we processed 12 very short GPS baselines(VSGB)with length<150 m.Themonument pairs for each baseline differ in their heights,horizontal structure,or base foundations.Meanwhile,two zero-baselines were also processed as the control group.Results showed that the sea-sonal signals observed in VSGB time series in the horizontal and vertical directions,were mainly inducedby seasonal MTE.Time-varying diurnal and semidiurnal signals with amplitude up to 4 mm wereobserved in the vertical direction for baselines with monument height difference(MHD)larger than10 m.Horizontal diurnal signal with an amplitude of about 2 mm was also detected for baselines withnon-axisymmetric monument structure.The orientation of the detected horizontal displacement wascoherent with the direction of daily temperature variation(DTV)driven by direct solar radiation,whichindicates that the diurnal and semidiurnal signals are likely induced by MTE.The observed high-frequency MTE displacements,if not well modeled and removed,may propagate into spurious long-term signals and bias the velocity estimation in the daily GPS time series.
基金Supported by the National Natural Science Foundation of China(No.2 9975 0 33)
文摘The drifting baselines of capillary electrophoresis affect the veracity of analysis greatly. This paper presents Threshold Fitting Technique(TFT) so as to subtract the baselines from the original signals and emendate the signals. In TFT, wavelet and curve fitting technique are applied synthetically, thresholds are decided by the computer automatically. Many experiments of signal processing indicate that TFT is simple for being used, there are few man-induced factors, and the results are satisfactory. TFT can be applied for noisy signals without any pre-processing.
文摘In the case of a medium-long baseline, for real-time kinematic (RTK) positioning, the fixed rate of integer ambiguity is low due to the distance between the base station and the observation station. Moreover, the atmospheric delay after differential processing cannot be ignored. For correcting the residual atmospheric errors, we proposed a GPS/BDS/Galileo/GLONASS four-system fusion RTK positioning algorithm, which is based on the extended Kalman filter (EKF) algorithm. After realizing the spatio-temporal unification of multiple global navigation satellite systems (GNSSs), we introduced a parameter estimation of atmospheric errors based on the EKF model, using the least-squares integer ambiguity decorrelation adjustment (LAMBDA) to calculate the integer ambiguity. After conducting experiments for different baselines, the proposed RTK positioning algorithm can achieve centimeter-level positioning accuracy in the case of medium-long baselines. In addition, the time required to solve the fixed solution is shorter than that of the traditional RTK positioning algorithm.
基金supported by the National Natural Science Foundation of China(42275194)the National Key Research andDevelopment Program of China(2023YFC3707404)Westlake University for the fruitful discussionof this work.We thank the technical support of the National LargeScientific and Technological Infrastructure‘Earth System Numerical Simulation Facility’(https://cstr.cn/31134.02.EL).
文摘Methane(CH4)is a very potent greenhouse gas with a globalwarming potential of approximately 80 times that of carbon dioxide(CO_(2))on a decadal scale[1].By November 2024,159 countrieshave signed the Global Methane Pledge,committing to reduceanthropogenic emissions by at least 30%by 2030 relative to the 2020 level(https://www.globalmethanepledge.org).In November2023,the Chinese government released an action plan dedicatedto methane emission control,including specific targets in differentsource sectors(https://www.mee.gov.cn/).However,large discrepancies still exist in China’s current methane inventories,hinderingthe setting of mitigation goals.By now,the national anthropogenicmethane emission estimates still vary by at least 30%,and sectoralemission estimates may differ by a factor of 2–5(Fig.1).To supportChina’s methane emission control plan,a key priority is to determine the emission baselines,which this work aims to address.
基金Supported by the Major Research Project of the Ninth-Five Plan(1996 2 0 0 0 ) of China!(No. 96 - 911- 0 3)
文摘To explore emission baseline, technically the most difficult issue for Clean Development Mechanism (CDM) project development, as well as to examine whether CDM is a possible way to help Beijing restructure its heating energy consumption, this paper conducts a CDM baseline case study on residential heating in Beijing. Based on investigation, energy consumption forecast and economic analysis of future technology options, the technology benchmark and site specific baselines for both retrofit projects and new heating projects have been discussed. The results indicate that fuel switching from coal to natural gas can meet the additionality criteria in many cases and will be the main type of CDM project. In addition, it also proves that the technology benchmark and the case by case baseline setting approach are applicable for future CDM cooperation projects on heating in Beijing.
文摘Basic communication standards that we rely upon reduce friction for consumers,customers and businesses,speed innovation and allow for cross-border collaboration among companies.That is critical for establishing global baselines of trust.What standards can do that politics cannot is to bring people together,encourage collaboration,and encourage trusting relationships and the ability to share and develop interoperable communication systems.Today we are building roads that lead to quantum technologies,artificial intelligence and blockchain technologies,but the rules of those roads are yet to be written.The industry has an important role to play in developing rules of the road.Those rules need to start with a very basic foundation,such as data identification secured by design standards,standards for privacy protection,and watermarking,tracing and accountability of AI technologies and algorithms.These are all very achievable objectives,and they form together a foundation of trust that customers and governments worldwide can rely upon.
基金funded by the National Key Research and Developmental Program of China(2022YFD1700200).
文摘The rice stem borer,Chilo suppressalis(Walker)(Lepidoptera:Crambidae),is one of the most serious pests in rice-growing areas,and it has developed resistance to most insecticides currently used in the field.Cyproflanilide is a novel meta-diamide insecticide that has shown high activities to multiple pests.Evaluating the risk of resistance to cyproflanilide in C.suppressalis is necessary for its preventive resistance management.Here we established the baseline susceptibility of C.suppressalis to cyproflanilide by the rice-seedling dipping method and topical application,and the LC_(50) and LD_(50) values were 0.026 mg L^(-1) and 0.122 ng/larva,respectively.The LC_(50) values of cyproflanilide in 37 field populations ranged from 0.012 to 0.061 mg L^(-1),and 25 field populations exhibited resistance to chlorantraniliprole with the highest LC_(50) value of 3,770.059 mg L^(-1).In addition,a logistic distribution model analysis indicated that only 0.048 mg L^(-1) of cyproflanilide was required to kill 90% field chlorantraniliprole-resistant populations of C.suppressalis,compared to 2,087.764 mg L^(-1) of chlorantraniliprole for a similar level of control.Resistance screening over 19 generations did not result in resistance to cyproflanilide(RR=3.1-fold).The realized heritability(h^(2))of resistance was estimated as 0.067 by using threshold trait analysis,suggesting a low risk of cyproflanilide resistance development in susceptible strains.The Cypro-SEL population(F_(10))had no obvious fitness cost(relative fitness=0.96),and no significant changes in sensitivity to seven tested insecticides.These findings suggested that cyproflanilide is a promising insecticide for the management of chlorantraniliprole-resistant C.suppressalis.Moreover,this integrated risk assessment provides scientific application guidelines for the sustainable resistance management of cyproflanilide for controlling C.suppressalis.
文摘This paper delves into the baseline design under the baseline parameterization model in experimental design, focusing on the relationship between the K-aberration criterion and the word length pattern (WLP) of regular two-level designs. The paper provides a detailed analysis of the relationship between K5and the WLP for regular two-level designs with resolution t=3, and proposes corresponding theoretical results. These results not only theoretically reveal the connection between the orthogonal parameterization model and the baseline parameterization model but also provide theoretical support for finding the K-aberration optimal regular two-level baseline designs. It demonstrates how to apply these theories to evaluate and select the optimal experimental designs. In practical applications, experimental designers can utilize the theoretical results of this paper to quickly assess and select regular two-level baseline designs with minimal K-aberration by analyzing the WLP of the experimental design. This allows for the identification of key factors that significantly affect the experimental outcomes without frequently changing the factor levels, thereby maximizing the benefits of the experiment.
基金supported by the Czech Science Foundation project GACR21-27454STechnology Agency of the Czech Republic(project Center for Landscape and Biodiversity,SS02030018).
文摘Extreme disturbance activity is a signature of anthropogenic environmental change. Empirical information describing the historical normative limits of disturbance regimes provides baseline data that facilitates the detection of contemporary trends in both disturbances and community-level responses. Quantifying the attributes of historical disturbances is challenging due to their transient episodic nature, with decades-to centurieslong intervals between recurrences. Unmanaged primary forests that support centuries-old trees therefore serve as unique reference systems for quantifying past disturbance regimes. We surveyed relict stands of primary beech-dominated forests over wide environmental gradients in the Carpathian Mountains of Europe. We collected core samples from 3,026 trees in 208 field survey plots distributed across 13 forest stands in two countries. We used dendrochronological methods to analyze time-series of annually-resolved ring-width variation and to identify anomalous growth patterns diagnostic of past forest canopy removal. A 180-year record(1810–1990) of spatially and temporally explicit disturbance events(n =333) was compiled and used to derive s tatistical attributes of the disturbance regime. We quantified disturbance severity(canopy area lost), patch size, and return intervals. Our analyses describe a complex regime where a background of relatively frequent, smallscale, low-to intermediate-severity disturbance was punctuated by episodic large-scale high-severity events. Even the most severe events were non-catastrophic at a stand level, leaving significant residual tree cover that supported a continuity of ecological function. We did not detect evidence for an expected climate-induced intensification of disturbance with time, but methodological limitations precluded an assessment of disturbance activity in the decades since 1990.
基金funded by National Natural Science Foundation of China(NSFC)(Nos.12075053,11505021 and 11975068)by National Key R&D Program of China(No.2022YFE 03060002)+1 种基金by Fundamental Research Funds for the Central Universities(No.2232024G-10)supported by the U.S.DoE Office of Science(No.DE-FG02–95ER54309)。
文摘Toroidal torques,generated by the resonant magnetic perturbation(RMP)and acting on the plasma column,are numerically systematically investigated for an ITER baseline scenario.The neoclassical toroidal viscosity(NTV),in particular the resonant portion,is found to provide the dominant contribution to the total toroidal torque under the slow plasma flow regime in ITER.While the electromagnetic torque always opposes the plasma flow,the toroidal torque associated with the Reynolds stress enhances the plasma flow independent of the flow direction.A peculiar double-peak structure for the net NTV torque is robustly computed for ITER,as the toroidal rotation frequency is scanned near the zero value.This structure is found to be ultimately due to a non-monotonic behavior of the wave-particle resonance integral(over the particle pitch angle)in the superbanana plateau NTV regime in ITER.These findings are qualitatively insensitive to variations of a range of factors including the wall resistivity,the plasma pedestal flow and the assumed frequency of the rotating RMP field.
基金Supported by the Project of Investigation on the Background and Quality of Representative Intertidal Sediments in China and Compilation of Atlas,Ministry of Science and Technology of the People’s Republic of China(No.2014FY210600)the National Natural Science Foundation of China(No.41807247)。
文摘The intertidal zone of mangroves has a significant impact on the ecological environment by serving as a crucial habitat for a wide range of organisms.When assessing heavy metal contamination in sediments within this zone,it is essential to establish a regional geochemical baseline that accounts for natural variations.In this study,regional geochemical baselines of heavy metals were established based on core sediment samples collected from Dongzhai Harbor in November 2015.Linear regression analysis was employed to examine the correlations between heavy metals and potential normalized elements.Subsequently,the sediment quality and intensity of pollutant input in the sediments of a mangrove intertidal zone were evaluated with enrichment factor(EF)and excessive influx of heavy metals.The EF values for Cr,Cd,Pb,Zn,and Ni in the study area were all below 1.5,indicating minimal levels of contamination;however,minor Cu contamination was observed in the high tidal flat area due to potential terrestrial inputs.These findings suggest that the overall environmental quality about heavy metals was good within the intertidal zone of mangroves.Moreover,as for the excess fluxes of heavy metals in intertidal sediments,there was consistency between influence and intervention of human activities on sedimentary environment during the selected period when examining variation trends.
文摘Sea topography information holds significant importance in oceanic research and the climate change detection.Radar imaging altimetry has emerged as the leading approach for global ocean observation,employing synthetic aperture radar(SAR)interferometry to enhance the spatial resolution of Sea topography.Nevertheless,current payload capacity and satellite hardware limitations prevent the extension of the interferometric baseline by enlarging the physical antenna size.This constraint hinders achieving centimeter-level accuracy in interferometric altimetry.To address this challenge,we conducted a numerical simulation to assess the viability of a large baseline interferometric imaging altimeter(LB-IIA).By controlling the baseline within the range of 600-1000 m through spiral orbit design in two satellites and mitigating baseline de-correlation with the carrier frequency shift(CFS)technique,we aimed to overcome the above limitations.Our findings demonstrate the efficacy of the CFS technique in compensating for baseline decoherence,elevating coherence from less than 0.1 to over 0.85.Concurrently.The height difference accuracy between neighboring sea surfaces reaches 1 cm within a 1 km resolution.This study is anticipated to serve as a foundational reference for future interferometric imaging altimeter development,catering to the demand for high-precision sea topography data in accurate global bathymetry inversion.
基金supported by the National Key Research and Development Program of China(Grant No.2023YFF1204803)the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20190736)+1 种基金the Fundamental Research Funds for the Central Universities(Grant No.NJ2024029)the National Natural Science Foundation of China(Grant Nos.81701346 and 62201265).
文摘The natural visibility graph method has been widely used in physiological signal analysis,but it fails to accurately handle signals with data points below the baseline.Such signals are common across various physiological measurements,including electroencephalograph(EEG)and functional magnetic resonance imaging(fMRI),and are crucial for insights into physiological phenomena.This study introduces a novel method,the baseline perspective visibility graph(BPVG),which can analyze time series by accurately capturing connectivity across data points both above and below the baseline.We present the BPVG construction process and validate its performance using simulated signals.Results demonstrate that BPVG accurately translates periodic,random,and fractal signals into regular,random,and scale-free networks respectively,exhibiting diverse degree distribution traits.Furthermore,we apply BPVG to classify Alzheimer’s disease(AD)patients from healthy controls using EEG data and identify non-demented adults at varying dementia risk using resting-state fMRI(rs-fMRI)data.Utilizing degree distribution entropy derived from BPVG networks,our results exceed the best accuracy benchmark(77.01%)in EEG analysis,especially at channels F4(78.46%)and O1(81.54%).Additionally,our rs-fMRI analysis achieves a statistically significant classification accuracy of 76.74%.These findings highlight the effectiveness of BPVG in distinguishing various time series types and its practical utility in EEG and rs-fMRI analysis for early AD detection and dementia risk assessment.In conclusion,BPVG’s validation across both simulated and real data confirms its capability to capture comprehensive information from time series,irrespective of baseline constraints,providing a novel method for studying neural physiological signals.
文摘Based on the finite element (FE) program ANSYS, a three-dimensional model for the Runyang Suspension Bridge (RSB) is established. The structural natural frequency, vibration mode, stress and displacement response under various load cases are given. A new method of FE model updating is presented based on the physical meaning of sensitivity and the penalty function concept. In this method, the structural model is updated by modifying the parameters of design, and validated by structural natural vibration characteristics, stress response as well as displacement response. The design parameters used for updating are bounded according to measured static response and engineering judgment. The FE model of RSB is updated and validated by the measurements coming from the structural health monitoring system (SHMS), and the FE baseline model reflecting the current state of RSB is achieved. Both the dynamic and static results show that the method is effective in updating the FE model of long span suspension bridges. The results obtained provide an important research basis for damage alarming and health monitoring of the RSB.
基金Supported by the National Natural Science Foundation of China under Grant No.60875071the High Technology Research and Development Program of China under Grant No.2007AA0676the Program for New Century Excellent Talents in University under Grant No.NCET-06-0877
文摘The authors proposed a moving long baseline algorithm based on the extended Kalman filter (EKF) for cooperative navigation and localization of multi-unmanned underwater vehicles (UUVs). Research on cooperative navigation and localization for multi-UUVs is important to solve navigation problems that restrict long and deep excursions. The authors investigated improvements in navigation accuracy. In the moving long base line (MLBL) structure, the master UUV is equipped with a high precision navigation system as a node of the moving long baseline, and the slave UUV is equipped with a low precision navigation system. They are both equipped with acoustic devices to measure relative location. Using traditional triangulation methods to calculate the position of the slave UUV may cause a faulty solution. An EKF was designed to solve this, combining the proprioceptive and exteroceptive sensors. Research results proved that the navigational accuracy is improved significantly with the MLBL method based on EKF.
基金Supported by Special Fund for Agro-scientific Research in the Public Interest of China(201303025)~~
文摘[Objective] This study aimed to avoid and delay the generation of resis- tance in Botrytis cinerea to boscalid. [Method] The sensitivity of Botrytis cinerea to boscalid was tested by the mycelial growth rate method. The distribution of sensitivity variation of B. cinerea to boscalid in different regions was cleared, and the sen- sitivity baseline of B. cinerea from Liaoning Province to boscalid was established. [Result] The ECso values of B. cinerea strains from Liaoning Province ranged from 0.080 0 to 7.787 2μg/ml, and the highest ECho value was 97.34 times higher than the minimum. The average EC50 value (1.973μg/ml) of the 158 strains was treated as the baseline sensitivity of B. cinerea from Liaoning Province to boscalid. [Conclu- sion] It is essential to conduct a risk assessment of drug resistance in B. cinerea to boscalid.