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Research on the Framework of Bias Detection and Elimination in Artificial Intelligence Algorithms
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作者 Haoxuan Lyu 《Sino-US English Teaching》 2025年第5期183-187,共5页
The excessive use of artificial intelligence(AI)algorithms has caused the problem of errors in AI algorithms,which has challenged the fairness of decision-making,and has intensified people’s inequality.Therefore,it i... The excessive use of artificial intelligence(AI)algorithms has caused the problem of errors in AI algorithms,which has challenged the fairness of decision-making,and has intensified people’s inequality.Therefore,it is necessary to conduct in-depth research and propose corresponding error detection and error elimination methods.This paper first proposes the root causes and threats of bias in AI algorithms,then summarizes the existing bias detection and error elimination methods,and proposes a bias processing framework in three-level dimensions of data,models,and conclusions,aiming to provide a framework for a comprehensive solution to errors in algorithms.At the same time,it also summarizes the problems and challenges in existing research and makes a prospect for future research trends.It is hoped that it will be helpful for us to build fairer AI. 展开更多
关键词 artificial intelligence(AI) algorithm bias bias detection bias elimination FAIRNESS framework research
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Cognitive Biases in Artificial Intelligence:Susceptibility of a Large Language Model to Framing Effect and Confirmation Bias
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作者 Li Hao Wang You Yang Xueling 《心理科学》 北大核心 2025年第4期892-906,共15页
The rapid advancement of Artificial Intelligence(AI)and Large Language Models(LLMs)has led to their increasing integration into various domains,from text generation and translation to question-answering.However,a crit... The rapid advancement of Artificial Intelligence(AI)and Large Language Models(LLMs)has led to their increasing integration into various domains,from text generation and translation to question-answering.However,a critical question remains:do these sophisticated models,much like humans,exhibit susceptibility to cognitive biases?Understanding the presence and nature of such biases in AI is paramount for assessing their reliability,enhancing their performance,and predicting their societal impact.This research specifically investigates the susceptibility of Google’s Gemini 1.5 Pro and DeepSeek,two prominent LLMs,to framing effects and confirmation bias.The study meticulously designed a series of experimental trials,systematically manipulating information proportions and presentation orders to evaluate these biases.In the framing effect experiment,a genetic testing decision-making scenario was constructed.The proportion of positive and negative information(e.g.,20%,50%,or 80%positive)and their presentation order were varied.The models’inclination towards undergoing genetic testing was recorded.For the confirmation bias experiment,two reports-one positive and one negative-about“RoboTaxi”autonomous vehicles were provided.The proportion of erroneous information within these reports(10%,30%,and 50%)and their presentation order were systematically altered,and the models’support for each report was assessed.The findings demonstrate that both Gemini 1.5 Pro and DeepSeek are susceptible to framing effects.In the genetic testing scenario,their decision-making was primarily influenced by the proportion of positive and negative information presented.When the proportion of positive information was higher,both models showed a greater inclination to recommend or proceed with genetic testing.Conversely,a higher proportion of negative information led to greater caution or a tendency not to recommend the testing.Importantly,the order in which this information was presented did not significantly influence their decisions in the framing effect scenarios.Regarding confirmation bias,the two models exhibited distinct behaviors.Gemini 1.5 Pro did not show an overall preference for either positive or negative reports.However,its judgments were significantly influenced by the order of information presentation,demonstrating a“recency effect,”meaning it tended to support the report presented later.The proportion of erroneous information within the reports had no significant impact on Gemini 1.5 Pro’s decisions.In contrast,DeepSeek exhibited an overall confirmation bias,showing a clear preference for positive reports.Similar to Gemini 1.5 Pro,DeepSeek’s decisions were also significantly affected by the order of information presentation,while the proportion of misinformation had no significant effect.These results reveal human-like cognitive vulnerabilities in advanced LLMs,highlighting critical challenges to their reliability and objectivity in decision-making processes.Gemini 1.5 Pro’s sensitivity to presentation order and DeepSeek’s general preference for positive information,coupled with its sensitivity to order,underscore the need for careful evaluation of potential cognitive biases during the development and application of AI.The study suggests that effective measures are necessary to mitigate these biases and prevent potential negative societal impacts.Future research should include a broader range of models for comparative analysis and explore more complex interactive scenarios to further understand and address these phenomena.The findings contribute significantly to understanding the limitations and capabilities of current AI systems,guiding their responsible development,and anticipating their potential societal implications. 展开更多
关键词 artificial intelligence large language models cognitive bias confirmation bias framing effect
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Impact of the Sequential Bias Correction Scheme on the CMA-MESO Numerical Weather Prediction Model
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作者 Yuxiao CHEN Liwen WANG +7 位作者 Daosheng XU Jeremy Cheuk-Hin LEUNG Yanan MA Shaojing ZHANG Jing CHEN Yi YANG Wenshou TIAN Banglin ZHANG 《Advances in Atmospheric Sciences》 2025年第8期1580-1596,共17页
Systematic bias is a type of model error that can affect the accuracy of data assimilation and forecasting that must be addressed.An online bias correction scheme called the sequential bias correction scheme(SBCS),was... Systematic bias is a type of model error that can affect the accuracy of data assimilation and forecasting that must be addressed.An online bias correction scheme called the sequential bias correction scheme(SBCS),was developed using the6 h average bias to correct the systematic bias during model integration.The primary purpose of this study is to investigate the impact of the SBCS in the high-resolution China Meteorological Administration Meso-scale(CMA-MESO)numerical weather prediction(NWP)model to reduce the systematic bias and to improve the data assimilation and forecast results through this method.The SBCS is improved upon and applied to the CMA-MESO 3-km model in this study.Four-week sequential data assimilation and forecast experiments,driven by rapid update and cycling(RUC),were conducted for the period from 2–29 May 2022.In terms of the characteristics of systematic bias,both the background and analysis show diurnal bias,and these large biases are affected by complex underlying surfaces(e.g.,oceans,coasts,and mountains).After the application of the SBCS,the results of the data assimilation show that the SBCS can reduce the systematic bias of the background and yield a neutral to slightly positive result for the analysis fields.In addition,the SBCS can reduce forecast errors and improve forecast results,especially for surface variables.The above results indicate that this scheme has good prospects for high-resolution regional NWP models. 展开更多
关键词 numerical weather prediction model error systematic bias bias correction SBCS
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Biased agonism of G protein-coupled receptors as a novel strategy for osteoarthritis therapy
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作者 Xiangbo Meng Ling Qin Xinluan Wang 《Bone Research》 2025年第3期555-569,共15页
Osteoarthritis(OA)is a prevalent degenerative joint disorder marked by chronic pain,inflammation,and cartilage loss,with current treatments limited to symptom relief.G protein-coupled receptors(GPCRs)play a pivotal ro... Osteoarthritis(OA)is a prevalent degenerative joint disorder marked by chronic pain,inflammation,and cartilage loss,with current treatments limited to symptom relief.G protein-coupled receptors(GPCRs)play a pivotal role in OA progression by regulating inflammation,chondrocyte survival,and matrix homeostasis.However,their multifaceted signaling,via G proteins orβ-arrestins,poses challenges for precise therapeutic targeting.Biased agonism,where ligands selectively activate specific GPCR pathways,emerges as a promising approach to optimize efficacy and reduce side effects.This review examines biased signaling in OAassociated GPCRs,including cannabinoid receptors(CB1,CB2),chemokine receptors(CCR2,CXCR4),protease-activated receptors(PAR-2),adenosine receptors(A1R,A2AR,A2BR,A3R),melanocortin receptors(MC1R,MC3R),bradykinin receptors(B2R),prostaglandin E2 receptors(EP-2,EP-4),and calcium-sensing receptors(CaSR).We analyze ligands in clinical trials and explore natural products from Traditional Chinese Medicine as potential biased agonists.These compounds,with diverse structures and bioactivities,offer novel therapeutic avenues.By harnessing biased agonism,this review underscores the potential for developing targeted,safer OA therapies that address its complex pathology,bridging molecular insights with clinical translation. 展开更多
关键词 OSTEOARTHRITIS G protein coupled receptors inflammation degenerative joint disorder g proteins ligands selectively activate biased agonism precise therapeutic targetingbiased agonismwhere
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Improving the Seasonal Forecast of Summer Precipitation in Southeastern China Using a CycleGAN-based Deep Learning Bias Correction Method 被引量:1
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作者 Song YANG Fenghua LING +1 位作者 Jing-Jia LUO Lei BAI 《Advances in Atmospheric Sciences》 2025年第1期26-35,共10页
Accurate seasonal precipitation forecasts,especially for extreme events,are crucial to preventing meteorological hazards and their potential impacts on national development,social activity,and security.However,the int... Accurate seasonal precipitation forecasts,especially for extreme events,are crucial to preventing meteorological hazards and their potential impacts on national development,social activity,and security.However,the intensity of summer precipitation is often largely underestimated in many current dynamic models.This study uses a deep learning method called Cycle-Consistent Generative Adversarial Networks(CycleGAN)to improve the seasonal forecasts for June-JulyAugust precipitation in southeastern China by the Nanjing University of Information Science and Technology Climate Forecast System(NUIST-CFS 1.0).The results suggest that the CycleGAN-based model significantly improves the accuracy in predicting the spatiotemporal distribution of summer precipitation compared to the traditional quantile mapping(QM)method.Using the unpaired bias-correction model,we can also obtain advanced forecasts of the frequency,intensity,and duration of extreme precipitation events over the dynamic model predictions.This study expands the potential applications of deep learning models toward improving seasonal precipitation forecasts. 展开更多
关键词 bias correction CycleGAN QM NUIST-CFS 1.0 extreme precipitation
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Magnetic resonance imaging bias field correction improves tumor prognostic evaluation after transcatheter arterial chemoembolization for liver cancer 被引量:1
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作者 Ke Liu Jun-Biao Li +1 位作者 Yong Wang Yan Li 《World Journal of Gastrointestinal Surgery》 2025年第4期207-220,共14页
BACKGROUND Transcatheter arterial chemoembolization(TACE)is a key treatment approach for advanced invasive liver cancer(infiltrative hepatocellular carcinoma).However,its therapeutic response can be difficult to evalu... BACKGROUND Transcatheter arterial chemoembolization(TACE)is a key treatment approach for advanced invasive liver cancer(infiltrative hepatocellular carcinoma).However,its therapeutic response can be difficult to evaluate accurately using conventional two-dimensional imaging criteria due to the tumor’s diffuse and multifocal growth pattern.Volumetric imaging,especially enhanced tumor volume(ETV),offers a more comprehensive assessment.Nonetheless,bias field inhomogeneity in magnetic resonance imaging(MRI)poses challenges,potentially skewing volumetric measurements and undermining prognostic evaluation.AIM To investigate whether MRI bias field correction enhances the accuracy of volumetric assessment of infiltrative hepatocellular carcinoma treated with TACE,and to analyze how this improved measurement impacts prognostic prediction.METHODS We retrospectively collected data from 105 patients with invasive liver cancer who underwent TACE treatment at the Affiliated Hospital of Xuzhou Medical University from January 2020 to January 2024.The improved N4 bias field correction algorithm was applied to process MRI images,and the ETV before and after treatment was calculated.The ETV measurements before and after correction were compared,and their relationship with patient prognosis was analyzed.A Cox proportional hazards model was used to evaluate prognostic factors,with Martingale residual analysis determining the optimal cutoff value,followed by survival analysis.RESULTS Bias field correction significantly affected ETV measurements,with the corrected baseline ETV mean(505.235 cm^(3))being significantly lower than before correction(825.632 cm^(3),P<0.001).Cox analysis showed that the hazard ratio(HR)for corrected baseline ETV(HR=1.165,95%CI:1.069-1.268)was higher than before correction(HR=1.063,95%CI:1.031-1.095).Using 412 cm^(3) as the cutoff,the group with baseline ETV<415 cm^(3) had a longer median survival time compared to the≥415 cm^(3) group(18.523 months vs 8.926 months,P<0.001).The group with an ETV reduction rate≥41%had better prognosis than the<41%group(17.862 months vs 9.235 months,P=0.006).Multivariate analysis confirmed that ETV reduction rate(HR=0.412,P<0.001),Child-Pugh classification(HR=0.298,P<0.001),and Barcelona Clinic Liver Cancer stage(HR=0.578,P=0.045)were independent prognostic factors.CONCLUSION Volume imaging based on MRI bias field correction can improve the accuracy of evaluating the efficacy of TACE treatment for invasive liver cancer.The corrected ETV and its reduction rate can serve as independent indicators for predicting patient prognosis,providing important reference for developing individualized treatment strategies. 展开更多
关键词 Invasive liver cancer Transcatheter arterial chemoembolization Magnetic resonance imaging bias field correction Volume imaging
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A Radar Countermeasure Modeling Method Incorporating Cognitive Bias
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作者 Wang Rui Li Xiangyang +2 位作者 Wang Dong Ma Hongguang Zhang Zhili 《系统仿真学报》 北大核心 2025年第4期1090-1101,共12页
Cognitive bias,stemming from electronic measurement error and variability in human perception,exists in cognitive electronic warfare and affects the outcomes of conflicts.In this paper,the dynamic game approach is emp... Cognitive bias,stemming from electronic measurement error and variability in human perception,exists in cognitive electronic warfare and affects the outcomes of conflicts.In this paper,the dynamic game approach is employed to develop a model for cognitive bias induced by incomplete information and measurement errors in cognitive radar countermeasures.The payoffs for both parties are calculated using the radar's anti-jamming strategy matrix A and the jammer's jamming strategy matrix B.With perfect Bayesian equilibrium,a dynamic radar countermeasure model is established,and the impact of cognitive bias is analyzed.Drawing inspiration from the cognitive bias analysis method used in stock market trading,a cognitive bias model for cognitive radar countermeasures is introduced,and its correctness is mathematically proved.A gaming scenario involving the AN/SPY-1 radar and a smart jammer is set up to analyze the influence of cognitive bias on game outcomes.Simulation results validate the effectiveness of the proposed method. 展开更多
关键词 cognitive electronic warfare cognitive bias radar countermeasure dynamic game perfect Bayesian equilibrium
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Event-related potentials reveal hypnotherapy's impact on attention bias in social anxiety disorder
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作者 Han Zhang Mi Zhang +8 位作者 Ni Li Wen-Zhuo Wei Lin-Xi Yang Yong-Yi Li Zhen-Yue Zu Li-Jun Ma Hui-Xue Wang Kai Wang Xiao-Ming Li 《World Journal of Psychiatry》 2025年第5期241-256,共16页
BACKGROUND Exploring hypnotherapy's potential to modulate attention bias offers promising avenues for treating social anxiety disorder(SAD).AIM To determine if hypnotherapy can alleviate social anxiety by influenc... BACKGROUND Exploring hypnotherapy's potential to modulate attention bias offers promising avenues for treating social anxiety disorder(SAD).AIM To determine if hypnotherapy can alleviate social anxiety by influencing attention bias,specifically identifying the aspects of attention processes affected by hypnosis.METHODS In this study,69 SAD participants were divided into three groups based on their Liebowitz Social Anxiety Scale scores:Experimental group,control group,and baseline group.The experimental group(n=23)underwent six weekly hypnosis sessions,while the control(n=23)and baseline groups(n=23)received no treatment.To evaluate alterations in SAD severity and attention bias towards threatening stimuli following hypnotherapy,we employed a combination of self-report questionnaires,an odd-one-out task,and electroencephalography recordings.RESULTS The experimental group showed significant reductions in P1,N170,N2pc,and late positive potential(LPP)brain wave activities during attention sensitivity and disengagement conditions.This indicates that hypnotherapy modulates early-stage face processing and later-stage emotional evaluation of threat-related stimuli in SAD patients.CONCLUSION Our findings highlight P1,N170,N2pc,and LPP as key neural markers in SAD treatment.By identifying these neural markers influenced by hypnotherapy,we offer insight into the mechanisms by which this treatment modality impacts attentional processes,potentially easing SAD symptoms. 展开更多
关键词 Social anxiety disorder Attention bias HYPNOTHERAPY Event-related potentials Face processing
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Skillful bias correction of offshore near-surface wind field forecasting based on a multi-task machine learning model
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作者 Qiyang Liu Anboyu Guo +5 位作者 Fengxue Qiao Xinjian Ma Yan-An Liu Yong Huang Rui Wang Chunyan Sheng 《Atmospheric and Oceanic Science Letters》 2025年第5期28-35,共8页
Accurate short-term forecast of offshore wind fields is still challenging for numerical weather prediction models.Based on three years of 48-hour forecast data from the European Centre for Medium-Range Weather Forecas... Accurate short-term forecast of offshore wind fields is still challenging for numerical weather prediction models.Based on three years of 48-hour forecast data from the European Centre for Medium-Range Weather Forecasts Integrated Forecasting System global model(ECMWF-IFS)over 14 offshore weather stations along the coast of Shandong Province,this study introduces a multi-task learning(MTL)model(TabNet-MTL),which significantly improves the forecast bias of near-surface wind direction and speed simultaneously.TabNet-MTL adopts the feature engineering method,utilizes mean square error as the loss function,and employs the 5-fold cross validation method to ensure the generalization ability of the trained model.It demonstrates superior skills in wind field correction across different forecast lead times over all stations compared to its single-task version(TabNet-STL)and three other popular single-task learning models(Random Forest,LightGBM,and XGBoost).Results show that it significantly reduces root mean square error of the ECMWF-IFS wind speed forecast from 2.20 to 1.25 m s−1,and increases the forecast accuracy of wind direction from 50%to 65%.As an explainable deep learning model,the weather stations and long-term temporal statistics of near-surface wind speed are identified as the most influential variables for TabNet-MTL in constructing its feature engineering. 展开更多
关键词 Forecast bias correction Wind field Multi-task learning Feature engineering Explainable AI
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Unveiling hidden biases in machine learning feature importance
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作者 Yoshiyasu Takefuji 《Journal of Energy Chemistry》 2025年第3期49-51,共3页
Nirmal et al.presented a machine learning-based design of ternary organic solar cells,utilizing feature importance[1].This paper highlights the alarming potential biases in the use of feature importance in machine lea... Nirmal et al.presented a machine learning-based design of ternary organic solar cells,utilizing feature importance[1].This paper highlights the alarming potential biases in the use of feature importance in machine learning,which can lead to incorrect conclusions and outcomes.Many scientists and researchers including Nirmal et al.are unaware that feature importances in machine learning in general are model-specific and do not necessarily represent true associations between the target and features. 展开更多
关键词 Machine learning Feature importance Potential bias Chi-squared and P-value
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Variations in optimal seismic intensity measures for shallowly buried bias loess tunnels
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作者 SUN Weiyu LIN Juncen +1 位作者 WANG Bo YAN Songhong 《Journal of Mountain Science》 2025年第5期1658-1673,共16页
Uneven terrain significantly increases the seismic risk of tunnels in loess deposits.To investigate the variations in optimal intensity measures(IMs)for shallowly buried loess tunnels considering biased terrain,nonlin... Uneven terrain significantly increases the seismic risk of tunnels in loess deposits.To investigate the variations in optimal intensity measures(IMs)for shallowly buried loess tunnels considering biased terrain,nonlinear dynamic analyses were conducted to obtain seismic responses validated by the actual damage pattern.Then IMs were evaluated based on the automatic calculation of the time history damage index fulfilled by a compiled Python program.Results showed that the plastic strain zone progressively developed and extended from the vault to the central slope surface with increasing seismic intensities,ultimately causing shear failure to the tunnel.For IMs at the slope top,peak ground velocity(PGV)(ζ=0.15),velocity spectrum intensity(VSI)(ζ=0.20),and peak spectrum velocity(PSv)(ζ=0.22)were all suitable for seismic fragility assessment.The VSI(ζ=0.17)was optimal,followed by PGV(ζ=0.19)and PSv(ζ=0.2)for those at the slope foot.Acceleration-related IMs were more sensitive to terrain variation.Comparative analyses demonstrated smaller damage probabilities for the IMs at the slope top than those at the slope foot under the same intensity level.The impact of unfavorable terrain on tunnels was accentuated as those located in uneven mountainous regions became more vulnerable to ground shaking. 展开更多
关键词 Shallowly buried bias Loess tunnels Slope failure Seismic intensity measures Fragility assessment
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Modulation of exchange bias in Py/IrMn films by surface acoustic waves
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作者 Jie Dong Shuai Mi +8 位作者 Meihong Liu Huiliang Wu Jinxuan Shi Huifang Qiao Qian Zhao Teng-Fei Zhang Chenbo Zhao Jianbo Wang Qingfang Liu 《Chinese Physics B》 2025年第8期765-770,共6页
We investigate the surface acoustic wave(SAW)modulation of the exchange bias field(H_(EB))in Py/IrMn films deposited on LiNbO_(3)substrates.We measured the anisotropic magnetoresistance(AMR)of the multilayer film when... We investigate the surface acoustic wave(SAW)modulation of the exchange bias field(H_(EB))in Py/IrMn films deposited on LiNbO_(3)substrates.We measured the anisotropic magnetoresistance(AMR)of the multilayer film when continuous SAW or pulsed SAW were applied and obtained H_(EB).With continuous SAW,the H_(EB)decreases continuously with power.While in the case of pulsed SAW,the H_(EB)first decreases and then stabilizes.Compared to pulsed SAW,the thermal effects from the continuous SAW lead to the continuous decrease of H_(EB)at higher SAW power,which is verified by the measurement of H_(EB)at different temperatures and input currents.Furthermore,our results show that pulsed SAW can effectively avoid thermal effects.The decrease of H_(EB)at smaller power in both continuous and pulsed SAW is mainly due to the SAW-induced dynamic strain field,which leads to a small perturbation in the magnetic moment of the FM layer.Combined with the AMR values measured at different angles during the saturation field,we believe that the SAW-induced dynamic strain field causes a 15°angle between the magnetic moment and the easy axis.Our experiments provide a different approach to manipulating H_(EB),opening up a potential avenue for future manipulation of antiferromagnetic moments. 展开更多
关键词 exchange bias surface acoustic wave anisotropic magnetoresistance thermal effect
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A graph neural network and multi-task learning-based decoding algorithm for enhancing XZZX code stability in biased noise
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作者 Bo Xiao Zai-Xu Fan +2 位作者 Hui-Qian Sun Hong-Yang Ma Xing-Kui Fan 《Chinese Physics B》 2025年第5期250-257,共8页
Quantum error correction is a technique that enhances a system’s ability to combat noise by encoding logical information into additional quantum bits,which plays a key role in building practical quantum computers.The... Quantum error correction is a technique that enhances a system’s ability to combat noise by encoding logical information into additional quantum bits,which plays a key role in building practical quantum computers.The XZZX surface code,with only one stabilizer generator on each face,demonstrates significant application potential under biased noise.However,the existing minimum weight perfect matching(MWPM)algorithm has high computational complexity and lacks flexibility in large-scale systems.Therefore,this paper proposes a decoding method that combines graph neural networks(GNN)with multi-classifiers,the syndrome is transformed into an undirected graph,and the features are aggregated by convolutional layers,providing a more efficient and accurate decoding strategy.In the experiments,we evaluated the performance of the XZZX code under different biased noise conditions(bias=1,20,200)and different code distances(d=3,5,7,9,11).The experimental results show that under low bias noise(bias=1),the GNN decoder achieves a threshold of 0.18386,an improvement of approximately 19.12%compared to the MWPM decoder.Under high bias noise(bias=200),the GNN decoder reaches a threshold of 0.40542,improving by approximately 20.76%,overcoming the limitations of the conventional decoder.They demonstrate that the GNN decoding method exhibits superior performance and has broad application potential in the error correction of XZZX code. 展开更多
关键词 quantum error correction XZZX code biased noise graph neural network
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Bias characteristics of cloud diurnal variation in the FGOALS-f3-L model
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作者 Hongtao Yang Guoxing Chen +1 位作者 Qing Bao Bian He 《Atmospheric and Oceanic Science Letters》 2025年第6期65-70,共6页
Cloud diurnal variation is crucial for regulating cloud radiative effects and atmospheric dynamics.However,it is often overlooked in the evaluation and development of climate models.Thus,this study aims to investigate... Cloud diurnal variation is crucial for regulating cloud radiative effects and atmospheric dynamics.However,it is often overlooked in the evaluation and development of climate models.Thus,this study aims to investigate the daily mean(CFR)and diurnal variation(CDV)of cloud fraction across high-,middle-,low-level,and total clouds in the FGOALS-f3-L general circulation model.The bias of total CDV is decomposed into the model biases in CFRs and CDVs of clouds at all three levels.Results indicate that the model generally underestimates low-level cloud fraction during the daytime and high-/middle-level cloud fraction at nighttime.The simulation biases of low clouds,especially their CDV biases,dominate the bias of total CDV.Compensation effects exist among the bias decompositions,where the negative contributions of underestimated daytime low-level cloud fraction are partially offset by the opposing contributions from biases in high-/middle-level clouds.Meanwhile,the bias contributions have notable land–ocean differences and region-dependent characteristics,consistent with the model biases in these variables.Additionally,the study estimates the influences of CFR and CDV biases on the bias of shortwave cloud radiative effects.It reveals that the impacts of CDV biases can reach half of those from CFR biases,highlighting the importance of accurate CDV representation in climate models. 展开更多
关键词 Cloud fraction Diurnal variation Climate model Model bias dissection Shortwave cloud radiative effects
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Signal estimation bias in x-ray dark-field imaging using dual phase grating interferometer
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作者 Zhi-Li Wang Zun Zhang +1 位作者 Heng Chen Xin Ge 《Chinese Physics B》 2025年第3期550-558,共9页
In x-ray dark-field imaging using dual phase grating interferometer,multi-contrast signals are extracted from a set of acquired phase-stepping data by using the least-squares fitting algorithm.The extracted mean inten... In x-ray dark-field imaging using dual phase grating interferometer,multi-contrast signals are extracted from a set of acquired phase-stepping data by using the least-squares fitting algorithm.The extracted mean intensity,amplitude and visibility signals may be intrinsically biased.However,it is still unclear how large these biases are and how the data acquisition parameters influence the biases in the extracted signals.This work set out to address these questions.Analytical expressions of the biases of the extracted signals were theoretically derived by using a second-order Taylor series expansion.Extensive numerical simulations were performed to validate the theoretical results.It is illustrated that while the estimated mean intensity signal is always unbiased,the estimated amplitude and visibility signals are both positively biased.While the biases of the estimated amplitude signals are proportional to the inverse of the total number of phase steps,the biases of the estimated visibility signals are inversely proportional to the product of the total number of phase steps and the mean number of photons counted per phase step.Meanwhile,it is demonstrated that the dependence of the biases on the mean visibility is quite different from that of Talbot-Lau interferometer due to the difference in the intensity model.We expect that these results can be useful for data acquisition optimizations and interpretation of x-ray dark-field images. 展开更多
关键词 x-ray imaging dual phase grating interferometer dark-field imaging signal bias
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The components of threat-related attentional biases among individuals with different levels of sense of control
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作者 Shunying Zhao Baojuan Ye +1 位作者 Min Rao Yulan Guo 《Journal of Psychology in Africa》 2025年第4期463-470,共8页
This study investigated how components of threat-related attentional biases are associated with levels of sense of control.Utilizing a using a spatial-cueing paradigm,36 college students with a high sense of control(f... This study investigated how components of threat-related attentional biases are associated with levels of sense of control.Utilizing a using a spatial-cueing paradigm,36 college students with a high sense of control(females=22,Mage=19.44,SD=1.36)and 35 with a low sense of control(females=15,Mage=19.77,SD=1.40)were assigned to task featuring different cue-target intervals(i.e.,50 and 800 ms).The student participants completed the Control Sense Scale,the GAD-7 Anxiety Scale,and the PHQ-9 Patient Health Questionnaire.Data from employing spatial-cueing task procedure,would provide the evidence on any differences in attentional biases toward threat images between the two groups.A repeated measures ANOVA indicated that both groups to exhibit attentional avoidance under the 50 ms interval condition.However,individuals in the low sense of control group(i.e.,LSC Group)demonstrated exacerbation of avoidance compared to those in the high sense of control group(i.e.,HSC Group).The current study did notfind any attentional bias components under the 800 ms interval condition.Thefindings provide preliminary evidence for a new vigilance-avoidance model for further study with a view to developing interventions targeting negative emotional disorders based on individuals’sense of control. 展开更多
关键词 high sense of control low sense of control threat-related attentional bias attentional avoidance
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Enhancing rectal cancer liver metastasis prediction:Magnetic resonance imaging-based radiomics,bias mitigation,and regulatory considerations
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作者 Yuwei Zhang 《World Journal of Gastrointestinal Oncology》 2025年第2期318-321,共4页
In this article,we comment on the article by Long et al published in the recent issue of the World Journal of Gastrointestinal Oncology.Rectal cancer patients are at risk for developing metachronous liver metastasis(M... In this article,we comment on the article by Long et al published in the recent issue of the World Journal of Gastrointestinal Oncology.Rectal cancer patients are at risk for developing metachronous liver metastasis(MLM),yet early prediction remains challenging due to variations in tumor heterogeneity and the limitations of traditional diagnostic methods.Therefore,there is an urgent need for noninvasive techniques to improve patient outcomes.Long et al’s study introduces an innovative magnetic resonance imaging(MRI)-based radiomics model that integrates high-throughput imaging data with clinical variables to predict MLM.The study employed a 7:3 split to generate training and validation datasets.The MLM prediction model was constructed using the training set and subsequently validated on the validation set using area under the curve(AUC)and dollar-cost averaging metrics to assess performance,robustness,and generalizability.By employing advanced algorithms,the model provides a non-invasive solution to assess tumor heterogeneity for better metastasis prediction,enabling early intervention and personalized treatment planning.However,variations in MRI parameters,such as differences in scanning resolutions and protocols across facilities,patient heterogeneity(e.g.,age,comorbidities),and external factors like carcinoembryonic antigen levels introduce biases.Additionally,confounding factors such as diagnostic staging methods and patient comorbidities require further validation and adjustment to ensure accuracy and generalizability.With evolving Food and Drug Administration regulations on machine learning models in healthcare,compliance and careful consideration of these regulatory requirements are essential to ensuring safe and effective implementation of this approach in clinical practice.In the future,clinicians may be able to utilize datadriven,patient-centric artificial intelligence(AI)-enhanced imaging tools integrated with clinical data,which would help improve early detection of MLM and optimize personalized treatment strategies.Combining radiomics,genomics,histological data,and demographic information can significantly enhance the accuracy and precision of predictive models. 展开更多
关键词 Metachronous liver metastasis Radiomics Machine learning Rectal cancer Magnetic resonance imaging variability bias mitigation Food and Drug Administration regulations Predictive modeling
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Design and construction of two biased electrodes and preliminary experiments on the Keda Torus eXperiment
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作者 Jiaren WU Tao LAN +21 位作者 Ge ZHUANG Jie WU Wenzhe MAO Chen CHEN Xingkang WANG Peng DENG Qilong DONG Yongkang ZHOU Tianxiong WANG Pengcheng LU Zeqi BAI Yuhua HUANG Zhengwei WU Zian WEI Xiaohui WEN Hai WANG Chu ZHOU Ahdi LIU Jinlin XIE Hong LI Weixing DING Wandong LIU 《Plasma Science and Technology》 2025年第4期42-49,共8页
The electromagnetic turbulence in reversed field pinch(RFP)plasmas exhibits three-dimensional characteristics.Suppression of this turbulence is crucial for enhancing plasma confinement,necessitating control over the e... The electromagnetic turbulence in reversed field pinch(RFP)plasmas exhibits three-dimensional characteristics.Suppression of this turbulence is crucial for enhancing plasma confinement,necessitating control over the electric field or the current profile.To this end,two sets of electrodes have been designed and installed on the Keda Torus eXperiment(KTX)RFP device to manipulate the edge electric field and the edge parallel current profile.Subsequently,the edge radial electric field and edge parallel current profile control experiments are conducted.In the edge radial electric field control experiments,the edge radial electric field is altered under bias,accompanied with an increase in the electron density and plasma duration.However,under bias,both electrostatic and magnetic fluctuations are enhanced.In the edge parallel current profile control experiments,the results indicate that bias modifies the edge parallel current profile locally,leading to a localized increase in the field reversal depth and electron density.Additionally,a reduction in magnetic fluctuations is observed within the reversed field enhanced region under bias,suggesting that the bias suppresses magnetic perturbations. 展开更多
关键词 KTX biased electrode radial electric field parallel current profile(Some figures may appear in colour only in the online journal)
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Controlling underestimation bias in reinforcement learning via minmax operation 被引量:1
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作者 Fanghui HUANG Yixin HE +2 位作者 Yu ZHANG Xinyang DENG Wen JIANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第7期406-417,共12页
Obtaining the accurate value estimation and reducing the estimation bias are the key issues in reinforcement learning.However,current methods that address the overestimation problem tend to introduce underestimation,w... Obtaining the accurate value estimation and reducing the estimation bias are the key issues in reinforcement learning.However,current methods that address the overestimation problem tend to introduce underestimation,which face a challenge of precise decision-making in many fields.To address this issue,we conduct a theoretical analysis of the underestimation bias and propose the minmax operation,which allow for flexible control of the estimation bias.Specifically,we select the maximum value of each action from multiple parallel state-action networks to create a new state-action value sequence.Then,a minimum value is selected to obtain more accurate value estimations.Moreover,based on the minmax operation,we propose two novel algorithms by combining Deep Q-Network(DQN)and Double DQN(DDQN),named minmax-DQN and minmax-DDQN.Meanwhile,we conduct theoretical analyses of the estimation bias and variance caused by our proposed minmax operation,which show that this operation significantly improves both underestimation and overestimation biases and leads to the unbiased estimation.Furthermore,the variance is also reduced,which is helpful to improve the network training stability.Finally,we conduct numerous comparative experiments in various environments,which empirically demonstrate the superiority of our method. 展开更多
关键词 Reinforcement learning Minmax operation Estimation bias Underestimation bias Variance
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