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Stepped-up development of accelerator mass spectrometry method for the detection of ^(60)Fe with the HI-13 tandem accelerator 被引量:1
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作者 Yang Zhang Sheng-Quan Yan +36 位作者 Ming He Qing-Zhang Zhao Wen-Hui Zhang Chao-Xin Kan Jian-Ming Zhou Kang-Ning Li Xiao-Fei Wang Jian-Cheng Liu Zhao-Hua Peng Zhuo Liang Ai-Ling Li Jian Zheng Qi-Wen Fan Yun-Ju Li You-Bao Wang Zhi-Hong Li Yang-Ping Shen Ding Nan Wei Nan Yu-Qiang Zhang Jia-Ying-Hao Li Jun-Wen Tian Jiang-Lin Hou Chang-Xin Guo Zhi-Cheng Zhang Ming-Hao Zhu Yu-Wen Chen Yu-Chen Jiang Tao Tian Jin-Long Ma Yi-Hui Liu Jing-Yu Dong Run-Long Liu Mei-Yue-Nan Ma Yong-Shou Chen Wei-Ping Liu Bing Guo 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第4期136-143,共8页
The Moon provides a unique environment for investigating nearby astrophysical events such as supernovae.Lunar samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides... The Moon provides a unique environment for investigating nearby astrophysical events such as supernovae.Lunar samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)Fe.In this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13tandem accelerator at the China Institute of Atomic Energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following Q3D magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3 T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3)N_(4) foil was installed in front of the Q3D as an energy degrader.For particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the spectrograph.Finally,an^(60)Fe sample with an abundance of 1.125×10^(-10)was used to test the new AMS system.These results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)Ni.The sensitivity was assessed to be better than 4.3×10^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated. 展开更多
关键词 Accelerator mass spectrometry Wien filter Isobar separation SUPERNOVAE Chang'e-5 lunar samples
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Research on the Encapsulation Device for Lunar Samples
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作者 Yonggang Du Chunyong Wang +3 位作者 Haoling Li Ying Zhou Ming Ji Xuesong Wang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期104-117,共14页
The encapsulation of lunar samples is a core research area in the third phase of the Chinese Lunar Exploration Program.The seal assembly,opening and closing mechanism(OCM),and locking mechanism are the core components... The encapsulation of lunar samples is a core research area in the third phase of the Chinese Lunar Exploration Program.The seal assembly,opening and closing mechanism(OCM),and locking mechanism are the core components of the encapsulation device of the lunar samples,and the requirements of a tight seal,lightweight,and low power make the design of these core components difficult.In this study,a combined sealing assembly,OCM,and locking mechanism were investigated for the device.The sealing architecture consists of rubber and an Ag-In alloy,and a theory was built to analyze the seal.Experiments of the electroplate Au coating on the knife-edge revealed that the hermetic seal can be significantly improved.The driving principle for coaxial double-helical pairs was investigated and used to design the OCM.Moreover,a locking mechanism was created using an electric initiating explosive device with orifice damping.By optimizing the design,the output parameters were adjusted to meet the requirements of the lunar explorer.The experimental results showed that the helium leak rate of the test pieces were not more than 5×10^(-11) Pa·m^(3)·s^(-1),the minimum power of the OCM was 0.3 W,and the total weight of the principle prototype was 2.9 kg.The explosive driven locking mechanism has low impact.This investigation solved the difficulties in achieving tight seal,light weight,and low power for the lunar explorer,and the results can also be used to explore other extraterrestrial objects in the future. 展开更多
关键词 Lunar samples ENCAPSULATION Vacuum seal MECHANISM
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Effectiveness of Histopathological Examination of Ultrasound-guided Puncture Biopsy Samples for Diagnosis of Extrapulmonary Tuberculosis
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作者 GU Wen Fei SHI Xia +5 位作者 MA Xin YU Jun Lei XU Jin Chuan QIAN Cheng Cheng HU Zhi Dong ZHANG Hui 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第2期170-177,共8页
Objective To evaluate the diagnostic value of histopathological examination of ultrasound-guided puncture biopsy samples in extrapulmonary tuberculosis(EPTB).Methods This study was conducted at the Shanghai Public Hea... Objective To evaluate the diagnostic value of histopathological examination of ultrasound-guided puncture biopsy samples in extrapulmonary tuberculosis(EPTB).Methods This study was conducted at the Shanghai Public Health Clinical Center.A total of 115patients underwent ultrasound-guided puncture biopsy,followed by MGIT 960 culture(culture),smear,Gene Xpert MTB/RIF(Xpert),and histopathological examination.These assays were performed to evaluate their effectiveness in diagnosing EPTB in comparison to two different diagnostic criteria:liquid culture and composite reference standard(CRS).Results When CRS was used as the reference standard,the sensitivity and specificity of culture,smear,Xpert,and histopathological examination were(44.83%,89.29%),(51.72%,89.29%),(70.11%,96.43%),and(85.06%,82.14%),respectively.Based on liquid culture tests,the sensitivity and specificity of smear,Xpert,and pathological examination were(66.67%,72.60%),(83.33%,63.01%),and(92.86%,45.21%),respectively.Histopathological examination showed the highest sensitivity but lowest specificity.Further,we found that the combination of Xpert and histopathological examination showed a sensitivity of 90.80%and a specificity of 89.29%.Conclusion Ultrasound-guided puncture sampling is safe and effective for the diagnosis of EPTB.Compared with culture,smear,and Xpert,histopathological examination showed higher sensitivity but lower specificity.The combination of histopathology with Xpert showed the best performance characteristics. 展开更多
关键词 Extrapulmonary tuberculosis DIAGNOSIS BIOPSY Histopathological examination Puncture samples
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Exploring device physics of perovskite solar cell via machine learning with limited samples
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作者 Shanshan Zhao Jie Wang +8 位作者 Zhongli Guo Hongqiang Luo Lihua Lu Yuanyuan Tian Zhuoying Jiang Jing Zhang Mengyu Chen Lin Li Cheng Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期441-448,共8页
Perovskite solar cells(PsCs)have developed tremendously over the past decade.However,the key factors influencing the power conversion efficiency(PCE)of PSCs remain incompletely understood,due to the complexity and cou... Perovskite solar cells(PsCs)have developed tremendously over the past decade.However,the key factors influencing the power conversion efficiency(PCE)of PSCs remain incompletely understood,due to the complexity and coupling of these structural and compositional parameters.In this research,we demon-strate an effective approach to optimize PSCs performance via machine learning(ML).To address chal-lenges posed by limited samples,we propose a feature mask(FM)method,which augments training samples through feature transformation rather than synthetic data.Using this approach,squeeze-and-excitation residual network(SEResNet)model achieves an accuracy with a root-mean-square-error(RMSE)of 0.833%and a Pearson's correlation coefficient(r)of 0.980.Furthermore,we employ the permu-tation importance(PI)algorithm to investigate key features for PCE.Subsequently,we predict PCE through high-throughput screenings,in which we study the relationship between PCE and chemical com-positions.After that,we conduct experiments to validate the consistency between predicted results by ML and experimental results.In this work,ML demonstrates the capability to predict device performance,extract key parameters from complex systems,and accelerate the transition from laboratory findings to commercialapplications. 展开更多
关键词 Perovskite solar cell Machine learning Device physics Performance prediction Limited samples
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Shear mechanical properties and fracturing responses of layered rough jointed rock-like materials
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作者 Xinxin Nie Qian Yin +7 位作者 Manchao He Qi Wang Hongwen Jing Bowen Zheng Bo Meng Tianci Deng Zheng Jiang Jiangyu Wu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第11期2417-2434,共18页
This study aims to investigate mechanical properties and failure mechanisms of layered rock with rough joint surfaces under direct shear loading.Cubic layered samples with dimensions of 100 mm×100 mm×100 mm ... This study aims to investigate mechanical properties and failure mechanisms of layered rock with rough joint surfaces under direct shear loading.Cubic layered samples with dimensions of 100 mm×100 mm×100 mm were casted using rock-like materials,with anisotropic angle(α)and joint roughness coefficient(JRC)ranging from 15°to 75°and 2-20,respectively.The direct shear tests were conducted under the application of initial normal stress(σ_(n)) ranging from 1-4 MPa.The test results indicate significant differences in mechanical properties,acoustic emission(AE)responses,maximum principal strain fields,and ultimate failure modes of layered samples under different test conditions.The peak stress increases with the increasingαand achieves a maximum value atα=60°or 75°.As σ_(n) increases,the peak stress shows an increasing trend,with correlation coefficients R² ranging from 0.918 to 0.995 for the linear least squares fitting.As JRC increases from 2-4 to 18-20,the cohesion increases by 86.32%whenα=15°,while the cohesion decreases by 27.93%whenα=75°.The differences in roughness characteristics of shear failure surface induced byαresult in anisotropic post-peak AE responses,which is characterized by active AE signals whenαis small and quiet AE signals for a largeα.For a given JRC=6-8 andσ_(n)=1 MPa,asαincreases,the accumulative AE counts increase by 224.31%(αincreased from 15°to 60°),and then decrease by 14.68%(αincreased from 60°to 75°).The shear failure surface is formed along the weak interlayer whenα=15°and penetrates the layered matrix whenα=60°.Whenα=15°,as σ_(n) increases,the adjacent weak interlayer induces a change in the direction of tensile cracks propagation,resulting in a stepped pattern of cracks distribution.The increase in JRC intensifies roughness characteristics of shear failure surface for a smallα,however,it is not pronounced for a largeα.The findings will contribute to a better understanding of the mechanical responses and failure mechanisms of the layered rocks subjected to shear loads. 展开更多
关键词 layered samples anisotropic angle joint roughness coefficient mechanical properties acoustic emission response fracturing evolution failure modes
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Mechanical behavior of 2G NPR bolt anchored rock samples under static disturbance loading
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作者 WANG Jiong JIANG Jian +4 位作者 WANG Siyu CHANG Yiwen LIU Peng HE Manchao CHENG Shuang 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2494-2516,共23页
The deep mining of coal resources is accompanied by severe environmental challenges and various potential engineering hazards.The implementation of NPR(negative Poisson's ratio)bolts are capable of controlling lar... The deep mining of coal resources is accompanied by severe environmental challenges and various potential engineering hazards.The implementation of NPR(negative Poisson's ratio)bolts are capable of controlling large deformations in the surrounding rock effectively.This paper focuses on studying the mechanical properties of the NPR bolt under static disturbance load.The deep nonlinear mechanical experimental system was used to study the mechanical behavior of rock samples with different anchored types(unanchored/PR anchored/2G NPR anchored)under static disturbance load.The whole process of rock samples was taken by high-speed camera to obtain the real-time failure characteristics under static disturbance load.At the same time,the acoustic emission signal was collected to obtain the key characteristic parameters of acoustic emission such as acoustic emission count,energy,and frequency.The deformation at the failure of the samples was calculated and analyzed by digital speckle software.The findings indicate that the failure mode of rock is influenced by different types of anchoring.The peak failure strength of 2G NPR bolt anchored rock samples exhibits an increase of 6.5%when compared to the unanchored rock samples.The cumulative count and cumulative energy of acoustic emission exhibit a decrease of 62.16%and 62.90%,respectively.The maximum deformation of bearing capacity exhibits an increase of 59.27%,while the failure time demonstrates a delay of 42.86%.The peak failure strength of the 2G NPR bolt anchored ones under static disturbance load exhibits an increase of 5.94%when compared to the rock anchored by PR(Poisson's ratio)bolt.The cumulative count and cumulative energy of acoustic emission exhibit a decrease of 47.16%and 43.86%,respectively.The maximum deformation of the bearing capacity exhibits an increase of 50.43%,and the failure time demonstrates a delay of 32%.After anchoring by 2G NPR bolt,anchoring support effectively reduces the risk of damage caused by static disturbance load.These results demonstrate that the support effect of 2G NPR bolt materials surpasses that of PR bolt. 展开更多
关键词 Anchored rock samples Static disturbance load Acoustic emission characteristics Digital speckle Negative Poisson's ratio
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A Fault Detection Method for Electric Vehicle Battery System Based on Bayesian Optimization SVDD Considering a Few Faulty Samples
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作者 Miao Li Fanyong Cheng +2 位作者 Jiong Yang Maxwell Mensah Duodu Hao Tu 《Energy Engineering》 EI 2024年第9期2543-2568,共26页
Accurate and reliable fault detection is essential for the safe operation of electric vehicles.Support vector data description(SVDD)has been widely used in the field of fault detection.However,constructing the hypersp... Accurate and reliable fault detection is essential for the safe operation of electric vehicles.Support vector data description(SVDD)has been widely used in the field of fault detection.However,constructing the hypersphere boundary only describes the distribution of unlabeled samples,while the distribution of faulty samples cannot be effectively described and easilymisses detecting faulty data due to the imbalance of sample distribution.Meanwhile,selecting parameters is critical to the detection performance,and empirical parameterization is generally timeconsuming and laborious and may not result in finding the optimal parameters.Therefore,this paper proposes a semi-supervised data-driven method based on which the SVDD algorithm is improved and achieves excellent fault detection performance.By incorporating faulty samples into the underlying SVDD model,training deals better with the problem of missing detection of faulty samples caused by the imbalance in the distribution of abnormal samples,and the hypersphere boundary ismodified to classify the samplesmore accurately.The Bayesian Optimization NSVDD(BO-NSVDD)model was constructed to quickly and accurately optimize hyperparameter combinations.In the experiments,electric vehicle operation data with four common fault types are used to evaluate the performance with other five models,and the results show that the BO-NSVDD model presents superior detection performance for each type of fault data,especially in the imperceptible early and minor faults,which has seen very obvious advantages.Finally,the strong robustness of the proposed method is verified by adding different intensities of noise in the dataset. 展开更多
关键词 Fault detection vehicle battery system lithium batteries fault samples
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Assessment of Appropriateness of Diagnostic Lymph Node Tissue Collection from the Operating Theater and by Interventional Radiologist. A Clinical Audit
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作者 Kowthar Salman Hassan Divya Deodhar +1 位作者 Abdullah T. Al-Rawahi Mahmood H. Al Abri 《Advances in Infectious Diseases》 CAS 2024年第3期541-548,共8页
Background: Appropriate sample requesting, collecting and timely dispatch to the appropriate laboratory is essential in establishing diagnosis of pathologies with lesions. Much time and effort may be wasted if this is... Background: Appropriate sample requesting, collecting and timely dispatch to the appropriate laboratory is essential in establishing diagnosis of pathologies with lesions. Much time and effort may be wasted if this is not done according to certain standards. We conducted this study to assess the route of lymph node samples from requests to reaching the laboratories. Methods: We conducted an audit over a period from 4th June until 10th Aug 2023. Data for all the procedures performed over this period on lymph node samples (was entered into and analysed using Excel. Results: A total of eighteen samples for sixteen patients were obtained during this period. Median age of the patients was 34 years (19 - 73) with a M:F ratio of 5:11. Among the IR samples, nine samples were from the neck, three from inguinal area and one from axilla. Seven samples (53.8%) were tru-cut biopsies, six samples (46.15%) were FNA. All samples were sent to the pathology laboratory fixed in formalin. Samples for TB were sent only for five cases (31.25%) and for only two cases (12.5%) were samples sent for bacterial culture. For the OR samples, none were sent for either bacterial culture or TB. Overall, eight patients (50%) were not investigated for any infectious etiologies like brucella, toxoplasmosis, CMV, EBV plus other possible causes. Repeat sampling was required for 25% of patients (within and out of the audit period). Conclusions: to avoid delays in making diagnoses, it is paramount to consider infectious etiologies as possible diagnosis for lymphadenopathy and request appropriate investigations. This requires liaising with infectious diseases/clinical microbiology experts to guide regarding types of samples, types of media and timely dispatch to the correct laboratory. 展开更多
关键词 Clinical Audit Clinical Samples BIOPSIES Lymph Nodes Saline FORMALIN Quality Improvement
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Multi-Compartment SCFA Quantification in Human
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作者 Jérémy Monteiro Antoine Lefèvre +6 位作者 Diane Dufour-Rainfray Adeline Oury Gabrielle Chicheri Laurent Galineau Hélène Blasco Lydie Nadal-Desbarats Patrick Emond 《American Journal of Analytical Chemistry》 CAS 2024年第6期177-200,共24页
Short-chain fatty acids (SCFA) play an important role in human biochemistry. They originate primarily from the digestive system through carbohydrates microbial fermentation. Most SCFA produced in the colon are absorbe... Short-chain fatty acids (SCFA) play an important role in human biochemistry. They originate primarily from the digestive system through carbohydrates microbial fermentation. Most SCFA produced in the colon are absorbed by the intestinal wall and enter the bloodstream to be distributed throughout the body for multiple purposes. At the intestinal level, SCFA play a role in controlling fat storage and fatty acid metabolism. The effects of these beneficial compounds therefore concern overall health. They facilitate energy expenditure and are valuable allies in the fight against obesity and diabetes. SCFA are also involved in the regulation of the levels of several neurotransmitters such as GABA (γ-aminobutyric acid), glutamate, serotonin, dopamine, and norepinephrine. Their role is also highlighted in many inflammatory and neurodegenerative diseases such as Alzheimer’s disease (AD) or Parkinson’s disease (PD). To have a realistic picture of the distribution of SCFA in different biological compartments of the human body, we propose to study SCFA simultaneously in five human biological samples: feces, saliva, serum, cerebrospinal fluid (CSF), and urine, as well as in Dried Blood Spot (DBS). To evaluate their concentration and repeatability, we used 10 aliquots from pooled samples, analyzed by 3-nitrophenylhydrazine (3-NPH) derivation and liquid chromatography coupled with high sensitivity mass spectrometry (LC-QqQ-MS). We also evaluated the SCFA assay on Dried Blood Spot (DBS). In this work, we adapted the pre-analytical parts for each sample to be able to use a common calibration curve, thus facilitating multi-assay quantification studies and so being less time-consuming. Moreover, we proposed new daughter ions from the same neutral loss (43 Da) to quantify SCFAs, thus improving the sensitivity. In conclusion, our methodology, based on a unique calibration curve for all samples for each SCFA, is well-suited to quantified them in a clinical context. 展开更多
关键词 LC-MS 3-Nitrophenylhydrazine Short-Chain Fatty Acids Human Biological Samples Quantification
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Mosquito Control, Killing off the Females
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作者 Phi Tran 《Open Journal of Animal Sciences》 2024年第1期14-22,共9页
In addition to causing discomfort, female mosquitoes introduce disease-carrying viruses and bacteria into the bloodstream of their victims. There are numerous publications describing the uses of sugary mosquito baits ... In addition to causing discomfort, female mosquitoes introduce disease-carrying viruses and bacteria into the bloodstream of their victims. There are numerous publications describing the uses of sugary mosquito baits with promising results. Without temperature control measures however, these methods are mainly useful for only nectar-feeding insects, including male mosquitoes, because the warmth of the blood is a condition for the females to locate their meals. The efforts required to keep the baits fresh against the natural spoiling process make them less attractive or impractical to implement. These experiments address these issues by using warm baits of water, sugar, boric acid, and antibiotics. Overnight, the general areas became clear of blood-sucking female mosquitoes while in numbers, the harmless males concentrated into the immediate vicinities. Control vs. experiment protocol established no other logical explanation for this phenomenon other than that females were attracted and killed by the bait. As expected, there was no female mosquito’s activity in these areas. There weren’t many left to do the work. 展开更多
关键词 Mosquitoes Malaria Dengue Control TOXIC Sugar Bait ATSB Samples
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Calculation of Two-Tailed Exact Probability in the Wald-Wolfowitz One-Sample Runs Test
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作者 José Moral De La Rubia 《Journal of Data Analysis and Information Processing》 2024年第1期89-114,共26页
The objectives of this paper are to demonstrate the algorithms employed by three statistical software programs (R, Real Statistics using Excel, and SPSS) for calculating the exact two-tailed probability of the Wald-Wo... The objectives of this paper are to demonstrate the algorithms employed by three statistical software programs (R, Real Statistics using Excel, and SPSS) for calculating the exact two-tailed probability of the Wald-Wolfowitz one-sample runs test for randomness, to present a novel approach for computing this probability, and to compare the four procedures by generating samples of 10 and 11 data points, varying the parameters n<sub>0</sub> (number of zeros) and n<sub>1</sub> (number of ones), as well as the number of runs. Fifty-nine samples are created to replicate the behavior of the distribution of the number of runs with 10 and 11 data points. The exact two-tailed probabilities for the four procedures were compared using Friedman’s test. Given the significant difference in central tendency, post-hoc comparisons were conducted using Conover’s test with Benjamini-Yekutielli correction. It is concluded that the procedures of Real Statistics using Excel and R exhibit some inadequacies in the calculation of the exact two-tailed probability, whereas the new proposal and the SPSS procedure are deemed more suitable. The proposed robust algorithm has a more transparent rationale than the SPSS one, albeit being somewhat more conservative. We recommend its implementation for this test and its application to others, such as the binomial and sign test. 展开更多
关键词 RANDOMNESS Nonparametric Test Exact Probability Small Samples QUANTILES
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A Credit Card Fraud Model Prediction Method Based on Penalty Factor Optimization AWTadaboost 被引量:1
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作者 Wang Ning Siliang Chen +2 位作者 Fu Qiang Haitao Tang Shen Jie 《Computers, Materials & Continua》 SCIE EI 2023年第3期5951-5965,共15页
With the popularity of online payment, how to perform creditcard fraud detection more accurately has also become a hot issue. And withthe emergence of the adaptive boosting algorithm (Adaboost), credit cardfraud detec... With the popularity of online payment, how to perform creditcard fraud detection more accurately has also become a hot issue. And withthe emergence of the adaptive boosting algorithm (Adaboost), credit cardfraud detection has started to use this method in large numbers, but thetraditional Adaboost is prone to overfitting in the presence of noisy samples.Therefore, in order to alleviate this phenomenon, this paper proposes a newidea: using the number of consecutive sample misclassifications to determinethe noisy samples, while constructing a penalty factor to reconstruct thesample weight assignment. Firstly, the theoretical analysis shows that thetraditional Adaboost method is overfitting in a noisy training set, which leadsto the degradation of classification accuracy. To this end, the penalty factorconstructed by the number of consecutive misclassifications of samples isused to reconstruct the sample weight assignment to prevent the classifierfrom over-focusing on noisy samples, and its reasonableness is demonstrated.Then, by comparing the penalty strength of the three different penalty factorsproposed in this paper, a more reasonable penalty factor is selected.Meanwhile, in order to make the constructed model more in line with theactual requirements on training time consumption, the Adaboost algorithmwith adaptive weight trimming (AWTAdaboost) is used in this paper, so thepenalty factor-based AWTAdaboost (PF_AWTAdaboost) is finally obtained.Finally, PF_AWTAdaboost is experimentally validated against other traditionalmachine learning algorithms on credit card fraud datasets and otherdatasets. The results show that the PF_AWTAdaboost method has betterperformance, including detection accuracy, model recall and robustness, thanother methods on the credit card fraud dataset. And the PF_AWTAdaboostmethod also shows excellent generalization performance on other datasets.From the experimental results, it is shown that the PF_AWTAdaboost algorithmhas better classification performance. 展开更多
关键词 Credit card fraud noisy samples penalty factors AWTadaboost algorithm
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Yarn Quality Prediction for Small Samples Based on AdaBoost Algorithm 被引量:1
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作者 刘智玉 陈南梁 汪军 《Journal of Donghua University(English Edition)》 CAS 2023年第3期261-266,共6页
In order to solve the problems of weak prediction stability and generalization ability of a neural network algorithm model in the yarn quality prediction research for small samples,a prediction model based on an AdaBo... In order to solve the problems of weak prediction stability and generalization ability of a neural network algorithm model in the yarn quality prediction research for small samples,a prediction model based on an AdaBoost algorithm(AdaBoost model) was established.A prediction model based on a linear regression algorithm(LR model) and a prediction model based on a multi-layer perceptron neural network algorithm(MLP model) were established for comparison.The prediction experiments of the yarn evenness and the yarn strength were implemented.Determination coefficients and prediction errors were used to evaluate the prediction accuracy of these models,and the K-fold cross validation was used to evaluate the generalization ability of these models.In the prediction experiments,the determination coefficient of the yarn evenness prediction result of the AdaBoost model is 76% and 87% higher than that of the LR model and the MLP model,respectively.The determination coefficient of the yarn strength prediction result of the AdaBoost model is slightly higher than that of the other two models.Considering that the yarn evenness dataset has a weaker linear relationship with the cotton dataset than that of the yarn strength dataset in this paper,the AdaBoost model has the best adaptability for the nonlinear dataset among the three models.In addition,the AdaBoost model shows generally better results in the cross-validation experiments and the series of prediction experiments at eight different training set sample sizes.It is proved that the AdaBoost model not only has good prediction accuracy but also has good prediction stability and generalization ability for small samples. 展开更多
关键词 stability and generalization ability for small samples.Key words:yarn quality prediction AdaBoost algorithm small sample generalization ability
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A network meta-analysis on comparison of invasive and non-invasive sampling methods to characterize intestinal microbiota of birds
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作者 Tianlong Zhou Kasun H.Bodawatta Aiwu Jiang 《Avian Research》 SCIE CSCD 2023年第2期281-290,共10页
Birds maintain complex and intimate associations with a diverse community of microbes in their intestine.Multiple invasive and non-invasive sampling methods are used to characterize these communities to answer a multi... Birds maintain complex and intimate associations with a diverse community of microbes in their intestine.Multiple invasive and non-invasive sampling methods are used to characterize these communities to answer a multitude of eco-evolutionary questions related to host-gut microbiome symbioses.However,the comparability of these invasive and non-invasive sampling methods is sparse with contradicting findings.Through performing a network meta-analysis for 13 published bird gut microbiome studies,here we attempt to investigate the comparability of these invasive and non-invasive sampling methods.The two most used non-invasive sampling methods(cloacal swabs and fecal samples)showed significantly different results in alpha diversity and taxonomic relative abundances compared to invasive samples.Overall,non-invasive samples showed decreased alpha diversity compared to intestinal samples,but the alpha diversities of fecal samples were more comparable to the intestinal samples.On the contrary,the cloacal swabs characterized significantly lower alpha diversities than in intestinal samples,but the taxonomic relative abundances acquired from cloacal swabs were similar to the intestinal samples.Phylogenetic status,diet,and domestication degree of host birds also influenced the differences in microbiota characterization between invasive and non-invasive samples.Our results indicate a general pattern in microbiota differences among intestinal mucosal and non-invasive samples across multiple bird taxa,while highlighting the importance of evaluating the appropriateness of the microbiome sampling methods used to answer specific research questions.The overall results also suggest the potential importance of using both fecal and cloacal swab sampling together to properly characterize bird microbiomes. 展开更多
关键词 Avian microbiomes Cloacal swabs Fecal samples Intestinal samples Meta regressions
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Biosensors for waterborne virus detection: Challenges and strategies
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作者 Xixi Song Zina Fredj +4 位作者 Yuqiao Zheng Hongyong Zhang Guoguang Rong Sumin Bian Mohamad Sawan 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第11期1252-1268,共17页
Waterborne viruses that can be harmful to human health pose significant challenges globally,affecting health care systems and the economy.Identifying these waterborne pathogens is essential for preventing diseases and... Waterborne viruses that can be harmful to human health pose significant challenges globally,affecting health care systems and the economy.Identifying these waterborne pathogens is essential for preventing diseases and protecting public health.However,handling complex samples such as human and wastewater can be challenging due to their dynamic and complex composition and the ultralow concentration of target analytes.This review presents a comprehensive overview of the latest breakthroughs in waterborne virus biosensors.It begins by highlighting several promising strategies that enhance the sensing performance of optical and electrochemical biosensors in human samples.These strategies include optimizing bioreceptor selection,transduction elements,signal amplification,and integrated sensing systems.Furthermore,the insights gained from biosensing waterborne viruses in human samples are applied to improve biosensing in wastewater,with a particular focus on sampling and sample pretreatment due to the dispersion characteristics of waterborne viruses in wastewater.This review suggests that implementing a comprehensive system that integrates the entire waterborne virus detection process with high-accuracy analysis could enhance virus monitoring.These findings provide valuable insights for improving the effectiveness of waterborne virus detection,which could have significant implications for public health and environmental management. 展开更多
关键词 Waterborne viruses Biosensors OPTICAL ELECTROCHEMICAL Human samples WASTEWATER
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A computational framework for improving genetic variants identification from 5,061 sheep sequencing data
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作者 Shangqian Xie Karissa Isaacs +1 位作者 Gabrielle Becker Brenda M.Murdoch 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第6期2332-2344,共13页
Background Pan-genomics is a recently emerging strategy that can be utilized to provide a more comprehensive characterization of genetic variation.Joint calling is routinely used to combine identified variants across ... Background Pan-genomics is a recently emerging strategy that can be utilized to provide a more comprehensive characterization of genetic variation.Joint calling is routinely used to combine identified variants across multiple related samples.However,the improvement of variants identification using the mutual support information from mul-tiple samples remains quite limited for population-scale genotyping.Results In this study,we developed a computational framework for joint calling genetic variants from 5,061 sheep by incorporating the sequencing error and optimizing mutual support information from multiple samples’data.The variants were accurately identified from multiple samples by using four steps:(1)Probabilities of variants from two widely used algorithms,GATK and Freebayes,were calculated by Poisson model incorporating base sequencing error potential;(2)The variants with high mapping quality or consistently identified from at least two samples by GATK and Freebayes were used to construct the raw high-confidence identification(rHID)variants database;(3)The high confidence variants identified in single sample were ordered by probability value and controlled by false discovery rate(FDR)using rHID database;(4)To avoid the elimination of potentially true variants from rHID database,the vari-ants that failed FDR were reexamined to rescued potential true variants and ensured high accurate identification variants.The results indicated that the percent of concordant SNPs and Indels from Freebayes and GATK after our new method were significantly improved 12%-32%compared with raw variants and advantageously found low frequency variants of individual sheep involved several traits including nipples number(GPC5),scrapie pathology(PAPSS2),sea-sonal reproduction and litter size(GRM1),coat color(RAB27A),and lentivirus susceptibility(TMEM154).Conclusion The new method used the computational strategy to reduce the number of false positives,and simulta-neously improve the identification of genetic variants.This strategy did not incur any extra cost by using any addi-tional samples or sequencing data information and advantageously identified rare variants which can be important for practical applications of animal breeding. 展开更多
关键词 Computational framework Genetic variants Multiple samples SHEEP
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Risk pre-assessment method for regional drilling engineering based on deep learning and multi-source data
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作者 Yu-Qiang Xu Kuan Liu +6 位作者 Bao-Lun He Tatiana Pinyaeva Bing-Shuo Li Yu-Cong Wang Jia-Jun Nie Lei Yang Fu-Xiang Li 《Petroleum Science》 SCIE EI CAS CSCD 2023年第6期3654-3672,共19页
Accurately predicting downhole risk before drilling in new exploration areas is one of the difficulties.Using intelligent algorithms to explore the complex relationship between multi-source data and downhole risk is a... Accurately predicting downhole risk before drilling in new exploration areas is one of the difficulties.Using intelligent algorithms to explore the complex relationship between multi-source data and downhole risk is a hot research topic and frontier in this field.However,due to the small number and uneven distribution of drilled wells in new exploration areas and the lack of sample data related to risk,the training model has insufficient generalization ability,and thus the prediction is not effective.In this paper,a drilling risk profile(depth domain)rich in geological and engineering information is constructed by introducing a quantitative evaluation method for drilling risk of drilled wells,which can provide sufficient risk sample data for model training and thus solve the small sample problem.For the problem of uneven distribution of drilling wells in new exploration areas,the concept of virtual wells and their deployment methods were proposed.Besides,two methods for calculating rock mechanical parameters of virtual wells were proposed,and the accuracy and applicability of the two methods are analyzed.The LSTM deep learning model was optimized to tap the quantitative relationship between drilling risk profiles and multi-source data(e.g.,seismic,logging,and rock mechanical parameters).The model was validated to have an average relative error of 9.19%.The quantitative prediction of the drilling risk profile of the virtual well was achieved using the trained LSTM model and the calculation of the relevant parameters of the virtual well.Finally,based on the sequential Gaussian simulation method and the risk distribution of drilled and virtual wells,a regional 3D drilling risk model was constructed.The analysis of real cases shows that the addition of virtual wells can significantly improve the identification of regional drilling risks and the prediction accuracy of pre-drill drilling risks in unexplored areas can be improved by up to 21%compared with the 3D risk model constructed based on drilled wells only. 展开更多
关键词 Pre-drill risk assessment Risk samples Deep learning LSTM neural network 3D model
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Fault Diagnosis of 5G Networks Based on Digital Twin Model
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作者 Xiaorong Zhu Lingyu Zhao +1 位作者 Jiaming Cao Jianhong Cai 《China Communications》 SCIE CSCD 2023年第7期175-191,共17页
Fault diagnosis of 5G networks faces the challenges of heavy reliance on human experience and insufficient fault samples and relevant monitoring data.The digital twin technology can realize the interaction between vir... Fault diagnosis of 5G networks faces the challenges of heavy reliance on human experience and insufficient fault samples and relevant monitoring data.The digital twin technology can realize the interaction between virtual space and physical space through the fusion of model and data,providing a new paradigm for fault diagnosis.In this paper,we first propose a network digital twin model and apply it to 5G network diagnosis.We then use an improved Average Wasserstein GAN with Gradient Penalty(AWGAN-GP)method to discover and predict failures in the twin network.Finally,we use XGBoost algorithm to locate the faults in physical network in real time.Extensive simulation results show that the proposed approach can significantly increase fault prediction and diagnosis accuracy in the case of a small number of labeled failure samples in 5G networks. 展开更多
关键词 5G networks fault diagnosis digital twin AWGAN-GP a small number of samples
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Measuring^(222)Rn in aquatic environment via Pulsed Ionization Chamber Radon Detector
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作者 Lijun Song Wen Liu +4 位作者 Shibin Zhao Chunqian Li Jinjia Guo Natasha Dimova Bochao Xu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第8期185-189,I0001-I0006,共11页
Radon(Rn)is a naturally occurring radioactive inert gas in nature,and^(222)Rn has been routinely used as a powerful tracer in various aquatic environmental research on timescales of hours to days,such as submarine gro... Radon(Rn)is a naturally occurring radioactive inert gas in nature,and^(222)Rn has been routinely used as a powerful tracer in various aquatic environmental research on timescales of hours to days,such as submarine groundwater discharge.Here we developed a new approach to measure^(222)Rn in discrete water samples with a wide range of^(222)Rn concentrations using a Pulsed Ionization Chamber(PIC)Radon Detector.The sensitivity of the new PIC system is evaluated at 6.06 counts per minute for 1 Bq/L when a 500 mL water sample volume is used.A robust logarithmic correlation between sample volumes,ranging from 250 mL to 5000 mL,and system sensitivity obtained in this study strongly suggests that this approach is suitable for measuring radon concentration levels in various natural waters.Compared to the currently available methods for measuring radon in grab samples,the PIC system is cheaper,easier to operate and does not require extra accessories(e.g.,drying tubes etc.)to maintain stable measurements throughout the counting procedure. 展开更多
关键词 ^(222)Rn radon measurement Pulsed Ionization Chamber Radon Detector radon in discrete water samples submarine groundwater discharge
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Ⅰ型左删失下Topp-Leone分布的参数及可靠度函数的估计
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作者 龙沁怡 徐丽平 《Chinese Quarterly Journal of Mathematics》 2023年第1期97-110,共14页
Firstly, the maximum likelihood estimate and asymptotic confidence interval of the unkown parameter for the Topp-Leone distribution are obtained under Type-I left censored samples, furthermore, the asymptotic confiden... Firstly, the maximum likelihood estimate and asymptotic confidence interval of the unkown parameter for the Topp-Leone distribution are obtained under Type-I left censored samples, furthermore, the asymptotic confidence interval of reliability function is obtained based on monotonicity. Secondly, under different loss functions, the Bayesian estimates of the unkown parameter and reliability function are obtained, and the expected mean square errors of Bayesian estimates are calculated. Monte-Carlo method is used to calculate the mean values and relative errors of the estimates. Finally, an example of life data is analyzed by using the statistical method in this paper. 展开更多
关键词 Topp-Leone distribution Type-I left censored samples Maximum likelihood estimate Bayesian estimate
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