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LociScan,a tool for screening genetic marker combinations for plant variety discrimination
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作者 Yang Yang Hongli Tian +5 位作者 Hongmei Yi Zi Shi Lu Wang Yaming Fan Fengge Wang Jiuran Zhao 《The Crop Journal》 SCIE CSCD 2024年第2期583-593,共11页
To reduce the cost and increase the efficiency of plant genetic marker fingerprinting for variety discrimination,it is desirable to identify the optimal marker combinations.We describe a marker combination screening m... To reduce the cost and increase the efficiency of plant genetic marker fingerprinting for variety discrimination,it is desirable to identify the optimal marker combinations.We describe a marker combination screening model based on the genetic algorithm(GA)and implemented in a software tool,Loci Scan.Ratio-based variety discrimination power provided the largest optimization space among multiple fitness functions.Among GA parameters,an increase in population size and generation number enlarged optimization depth but also calculation workload.Exhaustive algorithm afforded the same optimization depth as GA but vastly increased calculation time.In comparison with two other software tools,Loci Scan accommodated missing data,reduced calculation time,and offered more fitness functions.In large datasets,the sample size of training data exerted the strongest influence on calculation time,whereas the marker size of training data showed no effect,and target marker number had limited effect on analysis speed. 展开更多
关键词 Plant variety discrimination Genetic marker combination Variety discrimination power Genetic algorithm
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Discrimination of polysorbate 20 by high-performance liquid chromatography-charged aerosol detection and characterization for components by expanding compound database and library
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作者 Shi-Qi Wang Xun Zhao +10 位作者 Li-Jun Zhang Yue-Mei Zhao Lei Chen Jin-Lin Zhang Bao-Cheng Wang Sheng Tang Tom Yuan Yaozuo Yuan Mei Zhang Hian Kee Lee Hai-Wei Shi 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第5期722-732,共11页
Analyzing polysorbate 20(PS20)composition and the impact of each component on stability and safety is crucial due to formulation variations and individual tolerance.The similar structures and polarities of PS20 compon... Analyzing polysorbate 20(PS20)composition and the impact of each component on stability and safety is crucial due to formulation variations and individual tolerance.The similar structures and polarities of PS20 components make accurate separation,identification,and quantification challenging.In this work,a high-resolution quantitative method was developed using single-dimensional high-performance liquid chromatography(HPLC)with charged aerosol detection(CAD)to separate 18 key components with multiple esters.The separated components were characterized by ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UHPLC-Q-TOF-MS)with an identical gradient as the HPLC-CAD analysis.The polysorbate compound database and library were expanded over 7-time compared to the commercial database.The method investigated differences in PS20 samples from various origins and grades for different dosage forms to evaluate the composition-process relationship.UHPLC-Q-TOF-MS identified 1329 to 1511 compounds in 4 batches of PS20 from different sources.The method observed the impact of 4 degradation conditions on peak components,identifying stable components and their tendencies to change.HPLC-CAD and UHPLC-Q-TOF-MS results provided insights into fingerprint differences,distinguishing quasi products. 展开更多
关键词 Polysorbate 20 Component DATABASE discrimination Degradation
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The Analysis of the Correlation between SPT and CPT Based on CNN-GA and Liquefaction Discrimination Research
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作者 Ruihan Bai Feng Shen +2 位作者 Zihao Zhao Zhiping Zhang Qisi Yu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1159-1182,共24页
The objective of this study is to investigate themethods for soil liquefaction discrimination. Typically, predicting soilliquefaction potential involves conducting the standard penetration test (SPT), which requires f... The objective of this study is to investigate themethods for soil liquefaction discrimination. Typically, predicting soilliquefaction potential involves conducting the standard penetration test (SPT), which requires field testing and canbe time-consuming and labor-intensive. In contrast, the cone penetration test (CPT) provides a more convenientmethod and offers detailed and continuous information about soil layers. In this study, the feature matrix based onCPT data is proposed to predict the standard penetration test blow count N. The featurematrix comprises the CPTcharacteristic parameters at specific depths, such as tip resistance qc, sleeve resistance f s, and depth H. To fuse thefeatures on the matrix, the convolutional neural network (CNN) is employed for feature extraction. Additionally,Genetic Algorithm (GA) is utilized to obtain the best combination of convolutional kernels and the number ofneurons. The study evaluated the robustness of the proposed model using multiple engineering field data sets.Results demonstrated that the proposed model outperformed conventional methods in predicting N values forvarious soil categories, including sandy silt, silty sand, and clayey silt. Finally, the proposed model was employedfor liquefaction discrimination. The liquefaction discrimination based on the predicted N values was comparedwith the measured N values, and the results showed that the discrimination results were in 75% agreement. Thestudy has important practical application value for foundation liquefaction engineering. Also, the novel methodadopted in this research provides new ideas and methods for research in related fields, which is of great academicsignificance. 展开更多
关键词 CNN liquefaction discrimination SPT CPT
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FPGA implementation of 500-MHz high-count-rate high-time-resolution real-time digital neutron-gamma discrimination for fast liquid detectors
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作者 Hui‑Yin Shen Jing‑Long Zhang +1 位作者 Jie Zhang Jian‑Hang Zhou 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第8期101-113,共13页
Fast neutron flux measurements with high count rates and high time resolution have important applications in equipment such as tokamaks.In this study,real-time neutron and gamma discrimination was implemented on a sel... Fast neutron flux measurements with high count rates and high time resolution have important applications in equipment such as tokamaks.In this study,real-time neutron and gamma discrimination was implemented on a self-developed 500-Msps,12-bit digitizer,and the neutron and gamma spectra were calculated directly on an FPGA.A fast neutron flux measurement system with BC-501A and EJ-309 liquid scintillator detectors was developed and a fast neutron measurement experiment was successfully performed on the HL-2 M tokamak at the Southwestern Institute of Physics,China.The experimental results demonstrated that the system obtained the neutron and gamma spectra with a time accuracy of 1 ms.At count rates of up to 1 Mcps,the figure of merit was greater than 1.05 for energies between 50 keV and 2.8 MeV. 展开更多
关键词 Neutron-gamma discrimination Liquid scintillation detector Real-time spectrum analyzer
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The Influence of Price Discrimination from Airports on the Route Development Behavior of Airlines
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作者 Daniel Schnitzler 《Journal of Civil Engineering and Architecture》 2024年第1期17-29,共13页
Given the prominence and magnitude of airport incentive schemes,it is surprising that literature hitherto remains silent as to their effectiveness.In this paper,the relationship between airport incentive schemes and t... Given the prominence and magnitude of airport incentive schemes,it is surprising that literature hitherto remains silent as to their effectiveness.In this paper,the relationship between airport incentive schemes and the route development behavior of airlines is analyzed.Because of rare and often controversial findings in the extant literature regarding relevant influencing variables for attracting airlines at an airport,expert interviews are used as a complement to formulate testable hypotheses in this regard.A fixed effects regression model is used to test the hypotheses with a dataset that covers all seat capacity offered at the 22 largest German commercial airports in the week 46 from 2004 to 2011.It is found that incentives from primary choice,as well as secondary choice airports,have a significant influence on Low Cost Carriers.Furthermore,Low Cost Carriers,in general,do not leave any of both types of airports when the incentives cease.In the case of Network Carriers,no case is found where one joins a primary choice airport and receives an incentive.Insufficient data between Network Carriers and secondary choice airports in the time when incentives have ceased means that no statement can be given. 展开更多
关键词 AIRLINE rout development price discrimination
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Egg recognition and nestling discrimination in the Crested Myna(Acridotheres cristatellus):Size matters 被引量:3
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作者 Jinmei Liu Fangfang Zhang +1 位作者 Yuran Liu Wei Liang 《Avian Research》 SCIE CSCD 2023年第3期492-498,共7页
Most studies exploring abilities of hosts to detect brood parasitism are based on detecting colour and/or pattern differences among parasitic and host eggs or nestlings,while only few were focused on size differences.... Most studies exploring abilities of hosts to detect brood parasitism are based on detecting colour and/or pattern differences among parasitic and host eggs or nestlings,while only few were focused on size differences.True recognition and recognition by discordancy are used to explain cognitive mechanisms of host egg recognition;however,only a few studies have found that hosts use recognition by discordancy.This study investigated:1)whether egg and nestling recognitions in the Crested Myna(Acridotheres cristatellus) are based on size cues;2)whether the egg cognitive mechanism is recognition by discordancy based on size cues;and 3) whether the longer the experiment time,the higher the egg recognition rate.Our results showed that the Crested Myna uses egg or nestling size as a recognition cue while the egg and nestling colour and patterning are not associated with egg or nestling rejection,thus the cognitive mechanism of egg recognition in the Crested Myna is recognition by discordancy based on egg size cues.Furthermore,there is a rejection delay in time of egg rejection behaviour of the Crested Myna.Therefore,we suggest that the periodicity of egg rejection experiments could be appropriately extended,especially for species with relatively low egg recognition ability. 展开更多
关键词 Discordancy recognition Egg rejection Nest sanitation behaviour Nestling discrimination Rejection delay
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Performance of real‑time neutron/gamma discrimination methods 被引量:1
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作者 Shi‑Xing Liu Wei Zhang +5 位作者 Zi‑Han Zhang Shuang Lin Hong‑Rui Cao Cheng‑Xin Song Jin‑Long Zhao Guo‑Qiang Zhong 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第1期102-110,共9页
Nuclear security usually requires the simultaneous detection of neutrons and gamma rays.With the development of crystalline materials in recent years,Cs2LiLaBr6(CLLB)dual-readout detectors have attracted extensive att... Nuclear security usually requires the simultaneous detection of neutrons and gamma rays.With the development of crystalline materials in recent years,Cs2LiLaBr6(CLLB)dual-readout detectors have attracted extensive attention from researchers,where real-time neutron/gamma pulse discrimination is the critical factor among detector performance parameters.This study investigated the discrimination performance of the charge comparison,amplitude comparison,time comparison,and pulse gradient_(m)ethods and the effects of a Sallen–Key filter on their performance.Experimental results show that the figure of merit(FOM)of all four methods is improved by proper filtering.Among them,the charge comparison method exhibits excellent noise resistance;moreover,it is the most_(s)uitable method of real-time discrimination for CLLB detectors.However,its discrimination performance depends on the parameters t_(s),t_(m),and t_(e).When t_(s)corresponds to the moment at which the pulse is at 10%of its peak value,t_(e)requires a delay of only 640–740 ns compared to t_(s),at which time the potentially optimal FOM of the charge comparison method at 3.1–3.3 MeV is greater than 1.46.The FOM obtained using the t_(m)value calculated by a proposed maximized discrimination difference model(MDDM)and the potentially optimal FOM differ by less than 3.9%,indicating that the model can provide good guidance for parameter selection in the charge comparison method. 展开更多
关键词 Charge comparison Maximized discrimination difference model Pulse filtering Real time n-γdiscrimination
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Multi-Path Attention Inverse Discrimination Network for Offline Signature Verification
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作者 Xiaorui Zhang Yingying Wang +2 位作者 Wei Sun Qi Cui Xindong Wei 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期3057-3071,共15页
Signature verification,which is a method to distinguish the authenticity of signature images,is a biometric verification technique that can effectively reduce the risk of forged signatures in financial,legal,and other... Signature verification,which is a method to distinguish the authenticity of signature images,is a biometric verification technique that can effectively reduce the risk of forged signatures in financial,legal,and other business envir-onments.However,compared with ordinary images,signature images have the following characteristics:First,the strokes are slim,i.e.,there is less effective information.Second,the signature changes slightly with the time,place,and mood of the signer,i.e.,it has high intraclass differences.These challenges lead to the low accuracy of the existing methods based on convolutional neural net-works(CNN).This study proposes an end-to-end multi-path attention inverse dis-crimination network that focuses on the signature stroke parts to extract features by reversing the foreground and background of signature images,which effectively solves the problem of little effective information.To solve the problem of high intraclass variability of signature images,we add multi-path attention modules between discriminative streams and inverse streams to enhance the discriminative features of signature images.Moreover,a multi-path discrimination loss function is proposed,which does not require the feature representation of the samples with the same class label to be infinitely close,as long as the gap between inter-class distance and the intra-class distance is bigger than the set classification threshold,which radically resolves the problem of high intra-class difference of signature images.In addition,this loss can also spur the network to explore the detailed infor-mation on the stroke parts,such as the crossing,thickness,and connection of strokes.We respectively tested on CEDAR,BHSig-Bengali,BHSig-Hindi,and GPDS Synthetic datasets with accuracies of 100%,96.24%,93.86%,and 83.72%,which are more accurate than existing signature verification methods.This is more helpful to the task of signature authentication in justice and finance. 展开更多
关键词 Offline signatures biometric verification multi-path discrimination loss attention mechanisms inverse discrimination
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Sex effect on growth performance and marker-aided sex discrimination of seedlings of Populus deltoides
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作者 Yingnan Chen Huaitong Wu +4 位作者 Xiaogang Dai Weiqiang Li Yu Qiu Yonghua Yang Tongming Yin 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第5期1639-1645,共7页
Sex has a significant effect on various traits among dioecious plants.In this analysis of the sex effect on the radial growth and wood density of numerous 20-yearold trees of Populus deltoides growing in a common gard... Sex has a significant effect on various traits among dioecious plants.In this analysis of the sex effect on the radial growth and wood density of numerous 20-yearold trees of Populus deltoides growing in a common garden,male trees performed better than the females in radial growth,but sex did not significantly affect wood density.Growth rate and wood density were weakly negatively correlated.Sex selection is also critical for controlling seed-hair pollution from P.deltoides plantations.However,because the juvenile period of P.deltoides lasts for years,a reliable technique to determine the sex of juveniles has been needed.Here we developed a marker-aided technique to discriminate the sexes of P.deltoides seedlings.This study provides essential information on target traits and a highly desirable genetic toolkit for accelerate breeding programs for this important tree species. 展开更多
关键词 Sex effect Wood quality Growth performance Marker-aided selection Sex discrimination
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Quantitative Method of Classification and Discrimination of a Porous Carbonate Reservoir Integrating K-means Clustering and Bayesian Theory
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作者 FANG Xinxin ZHU Guotao +2 位作者 YANG Yiming LI Fengling FENG Hong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第1期176-189,共14页
Reservoir classification is a key link in reservoir evaluation.However,traditional manual means are inefficient,subjective,and classification standards are not uniform.Therefore,taking the Mishrif Formation of the Wes... Reservoir classification is a key link in reservoir evaluation.However,traditional manual means are inefficient,subjective,and classification standards are not uniform.Therefore,taking the Mishrif Formation of the Western Iraq as an example,a new reservoir classification and discrimination method is established by using the K-means clustering method and the Bayesian discrimination method.These methods are applied to non-cored wells to calculate the discrimination accuracy of the reservoir type,and thus the main reasons for low accuracy of reservoir discrimination are clarified.The results show that the discrimination accuracy of reservoir type based on K-means clustering and Bayesian stepwise discrimination is strongly related to the accuracy of the core data.The discrimination accuracy rate of TypeⅠ,TypeⅡ,and TypeⅤreservoirs is found to be significantly higher than that of TypeⅢand TypeⅣreservoirs using the method of combining K-means clustering and Bayesian theory based on logging data.Although the recognition accuracy of the new methodology for the TypeⅣreservoir is low,with average accuracy the new method has reached more than 82%in the entire study area,which lays a good foundation for rapid and accurate discrimination of reservoir types and the fine evaluation of a reservoir. 展开更多
关键词 UPSTREAM resource exploration reservoir classification CARBONATE K-means clustering Bayesian discrimination CENOMANIAN-TURONIAN Iraq
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Discrimination and quantification of scar tissue by Mueller matrix imaging with machine learning
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作者 Xi Liu Yanan Sun +3 位作者 Weixi Gu Jianguo Sun Yi Wang Li Li 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2023年第5期47-58,共12页
Scarring is one of the biggest areas of unmet need in the long-term success of glaucoma filtration surgery.Quantitative evaluation of the scar tissue and the post-operative structure with micron scale resolution facil... Scarring is one of the biggest areas of unmet need in the long-term success of glaucoma filtration surgery.Quantitative evaluation of the scar tissue and the post-operative structure with micron scale resolution facilitates development of anti-fibrosis techniques.However,the distinguishment of conjunctiva,sclera and the scar tissue in the surgical area still relies on pathologists'experience.Since polarized light imaging is sensitive to anisotropic properties of the media,it is ideal for discrimination of scar in the subconjunctival and episcleral area by characterizing small differences between proportion,organization and the orientation of the fibers.In this paper,we defined the conjunctiva,sclera,and the scar tissue as three target tissues after glaucoma filtration surgery and obtained their polarization characteristics from the tissue sections by a Mueller matrix microscope.Discrimination score based on parameters derived from Mueller matrix and machine learning was calculated and tested as a diagnostic index.As a result,the discrimination score of three target tissues showed significant difference between each other(p<0.001).The visualization of the discrimination results showed significant contrast between target tissues.This study proved that Mueller matrix imaging is effective in ocular scar discrimination and paves the way for its application on other forms of ocular fibrosis as a substitute or supplementary for clinical practice. 展开更多
关键词 Tissue discrimination glaucoma filtration surgery polarized light Mueller matrix machine learning.
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Do Chinese Women Face Subtle Discrimination in Job Hiring?
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作者 Shelly Y.Wu 《Psychology Research》 2023年第12期609-613,共5页
Gender discrimination has long been the problem that exists in the entire world,including China.However,as more and more people are focusing on the general gender discrimination,the group recognized an extension of su... Gender discrimination has long been the problem that exists in the entire world,including China.However,as more and more people are focusing on the general gender discrimination,the group recognized an extension of such discrimination-pregnancy discrimination in job hiring(the discrimination that women who are pregnant or have the inclination to pregnancy receive in hiring).The possible subtle pregnancy discrimination may be one of the main causes that lead to the declining fertility rate in China.The group decided to conduct an experiment to determine whether women are receiving more subtle discrimination in job hiring due to their identity as mother than men with children,men without children,and women without children.Using the form of questionary and resumes,the team found that Chinese women are indeed enduring subtle discrimination in work hiring.The experiment highlights the importance to promote further equality among women.However,there are some confounding variables,like the level of patient of the HR who reads the resume,affecting the ultimate result of the study.Keywords:gender discrimination,women’s career,Chinese job market,pregnancy discrimination,fertility rate in China. 展开更多
关键词 gender discrimination women’s career Chinese job market pregnancy discrimination fertility rate in China
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Artificial neural network algorithm for pulse shape discrimination in 2πα and 2πβ particle surface emission rate measurements
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作者 Yuan-Qiao Li Bao-Ji Zhu +4 位作者 Yang Lv Heng Zhu Min Lin Ke-Sheng Chen Li-Jun Xu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第10期91-102,共12页
To enhance the accuracy of 2πα and 2πβ particle surface emission rate measurements and address the identification issues of nuclides in conventional methods, this study introduces two artificial neural network(ANN... To enhance the accuracy of 2πα and 2πβ particle surface emission rate measurements and address the identification issues of nuclides in conventional methods, this study introduces two artificial neural network(ANN) algorithms: back-propagation(BP) and genetic algorithm-based back-propagation(GA-BP). These algorithms classify pulse signals from distinct α and β particles. Their discrimination efficacy is assessed by simulating standard pulse signals and those produced by contaminated sources, mixing α and β particles within the detector. This study initially showcases energy spectrum measurement outcomes, subsequently tests the ANNs on the measurement and validation datasets, and contrasts the pulse shape discrimination efficacy of both algorithms. Experimental findings reveal that the proportional counter's energy resolution is not ideal, thus rendering energy analysis insufficient for distinguishing between 2πα and 2πβ particles. The BP neural network realizes approximately 99% accuracy for 2πα particles and approximately 95% for 2πβ particles, thus surpassing the GA-BP's performance. Additionally, the results suggest enhancing β particle discrimination accuracy by increasing the digital acquisition card's threshold lower limit. This study offers an advanced solution for the 2πα and 2πβ surface emission rate measurement method, presenting superior adaptability and scalability over conventional techniques. 展开更多
关键词 Pulse shape discrimination Artificial neural networks Alpha and beta sources Multi-wire proportional counter Surface emission rate
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Pulse-shaping method for real-time neutron/gamma discrimination at low sampling rates
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作者 Jia‑Xin Li Hui‑Liang Hou +2 位作者 Yue‑Feng Huang Mao‑Song Cheng Zhi‑Min Dai 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第11期51-63,共13页
The Na I:Tl scintillator is an innovative material for dual-gamma-ray and neutron detection with a low ^(6)Li concentration.To achieve real-time n/γ discrimination,a zero-crossing time comparison algorithm based on t... The Na I:Tl scintillator is an innovative material for dual-gamma-ray and neutron detection with a low ^(6)Li concentration.To achieve real-time n/γ discrimination,a zero-crossing time comparison algorithm based on trapezoidal pulse shaping was developed.The algorithm can operate efficiently at low sampling rates and was implemented on a single-probe portable digital n/γ discriminator based on a field-programmable gate array.The discriminator and Na I:Tl,^(6)Li detector were tested in a neutron-gamma mixed field produced by an ^(241)Am-Be neutron source to evaluate the performance of the algorithm.The figure of merits was measured as 2.88 at a sampling rate of 50 MHz,indicating that the discriminator with its embedded algorithm has a promising n/γ discrimination capability.Efficient discrimination at sampling rates of 40 and 25 MHz demonstrates that the capability of this method is not limited by low sampling rates. 展开更多
关键词 FPGA NaI:Tl ^(6)Li Real time Neutron/gamma discrimination Pulse shaping
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Biopsychosocial impact of discrimination on cancer risk and outcome: A conceptual review
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作者 Bishal Patangia 《Psychosomatic Medicine Research》 2023年第4期5-14,共10页
Discrimination,a major social factor influencing health,can influence both the risk and course of cancer.The medical and psychological mechanisms through which discrimination can impact the onset and spread of cancer ... Discrimination,a major social factor influencing health,can influence both the risk and course of cancer.The medical and psychological mechanisms through which discrimination can impact the onset and spread of cancer are explored in depth in this conceptual evaluation.In addition to investigating the ethical aspects of discrimination in cancer research,it also studies the effects of bias on cancer detection and therapy.In addition,this review provides suggestions for reducing the effect of discrimination on cancer risk and outcomes.Discrimination,in particular,can trigger the growth and spread of cancer via various pathways,including stress,inflammation,and changes in epigenetic patterns.It can also affect the immune system,making the body more vulnerable to the proliferation of cancerous cells.Discrimination can result in hindrances or delays in the process of cancer screening and treatment,and it can influence the quality of care for individuals suffering from cancer.This can contribute to the presence of disparities in terms of cancer vulnerability,occurrence,mortality,and survival rates among different demographic groups.Various measures can be implemented to mitigate the impact of discrimination on cancer vulnerability and outcomes.These measures address the underlying causes of discrimination,ensure that all individuals have access to exceptional cancer care,promote the acquisition of cultural proficiency and anti-bias training by healthcare providers,and develop and implement interventions to reduce discrimination’s impact on cancer vulnerability,screening,and treatment. 展开更多
关键词 discrimination cancer risk health disparities INEQUALITY
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积极伦理观下算法歧视治理模式的革新 被引量:7
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作者 梅傲 《政治与法律》 北大核心 2024年第2期113-126,共14页
算法技术已借助大数据技术被广泛应用,成为影响人们日常生活的重要角色,其也因技术中立性不断遭受现实挑战而呈现出事实上的歧视性。重新审视算法歧视及其治理路径是发挥算法积极作用、避免算法消极影响的重要前提。传统伦理观念影响下... 算法技术已借助大数据技术被广泛应用,成为影响人们日常生活的重要角色,其也因技术中立性不断遭受现实挑战而呈现出事实上的歧视性。重新审视算法歧视及其治理路径是发挥算法积极作用、避免算法消极影响的重要前提。传统伦理观念影响下的算法歧视治理模式存在价值观念偏航、治理结构失衡及技术治理落后的问题,影响算法歧视治理实效。社会发展促进了伦理观念的革新,积极伦理观的树立可以为算法技术向善的实现提供理论指引。算法治理结构的优化及反歧视技术水平的提高是纠正算法歧视的重要前提,理念、制度及技术三维措施的综合运用方可在算法领域实现科技向善的伦理目标。 展开更多
关键词 算法歧视 积极伦理观 算法治理 科技向善
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算法歧视的敏捷治理——以D短视频平台为例 被引量:4
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作者 高进 刘聪 《西安交通大学学报(社会科学版)》 北大核心 2024年第1期121-132,共12页
敏捷治理作为社会治理的新范式,是对回应式治理和集中式治理的进阶和超越,是塑造未来数智世界和元宇宙治理的现实路径。以敏捷治理化解算法歧视的技术与伦理风险,实现算法治理成为一项重要的理论和现实议题。通过参与式调查对D短视频平... 敏捷治理作为社会治理的新范式,是对回应式治理和集中式治理的进阶和超越,是塑造未来数智世界和元宇宙治理的现实路径。以敏捷治理化解算法歧视的技术与伦理风险,实现算法治理成为一项重要的理论和现实议题。通过参与式调查对D短视频平台的内容展开田野调查,深度剖析短视频平台算法运作的逻辑机理,总结归纳算法歧视的形态和成因,探索尝试算法治理的可行举措和实践进路。研究发现,基于用户偏好、平台优先等平台价值观念是D短视频平台算法运作的隐形逻辑;主观设计下歧视性推送和定价是D短视频平台算法歧视的突出表现;灵敏感知、快速响应、持续发展的敏捷治理机制是逾越“算计”陷阱的有效手段。因而,为应对算法歧视的风险挑战,政府亟须以敏捷治理赋能算法歧视治理,塑造多元参与、多管齐下的治理格局,实现整体智治、协同共治、动态管治,从而实现算法“善治”,优化算法治理的中国方案。 展开更多
关键词 算法歧视 敏捷治理 算法治理 短视频平台
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IP属地化政策对舆情评论的影响研究——基于微博用户属地公开的准自然实验 被引量:1
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作者 乐承毅 孔维伟 段楠楠 《图书情报知识》 北大核心 2024年第1期46-57,共12页
[目的/意义]实证评估公开属地政策能否以及如何对舆情评论产生影响,为网络舆情研究、平台优化和治理提供启示。[研究设计/方法]基于自我监控理论和隐私计算理论构建研究模型和假设,以微博“IP属地”功能的推出为准自然实验,运用双重差... [目的/意义]实证评估公开属地政策能否以及如何对舆情评论产生影响,为网络舆情研究、平台优化和治理提供启示。[研究设计/方法]基于自我监控理论和隐私计算理论构建研究模型和假设,以微博“IP属地”功能的推出为准自然实验,运用双重差分法和断点回归模型探究IP属地化政策对舆情评论的影响。[结论/发现]政策引发用户自我监控效应和风险感知效应,不仅整体改善了评论情感倾向、评论可读性和共情性,也能够显著抑制评论情感极性,该结论在一系列稳健性检验后仍然成立。政策影响在不同用户群体之间存在显著差异,相较处于事件热点中心的用户,属地公开更能促使处于非热点中心的用户做出改变。政策同时加剧评论中的地域歧视现象。[创新/价值]揭示了IP属地化政策对在线评论行为的作用,为清朗网络环境提供新视角,丰富了IP属地化与舆情评论行为影响因素的相关研究。 展开更多
关键词 IP属地化 舆情评论 隐私计算理论 地域歧视 双重差分
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噪声鉴别C均值聚类的滁菊花茶品质等级鉴别研究
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作者 武斌 谢晨傲 +2 位作者 陈勇 武小红 贾红雯 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第8期2202-2207,共6页
近红外光谱检测技术可以通过探测近红外区域的光谱特征,反映所测样品内部有机物化学成分和结构信息。在分析物质成分时,近红外光谱通常会涉及到大量的波长数据,因此其维数往往比较高。同时,光谱会出现重叠和冗余等现象,会影响模型的性... 近红外光谱检测技术可以通过探测近红外区域的光谱特征,反映所测样品内部有机物化学成分和结构信息。在分析物质成分时,近红外光谱通常会涉及到大量的波长数据,因此其维数往往比较高。同时,光谱会出现重叠和冗余等现象,会影响模型的性能。提出一种噪声鉴别C均值聚类(NDCM)算法。NDCM将一种快速广义噪声聚类(FGNC)和模糊线性判别分析(FLDA)相结合,可实现模糊聚类过程中进行数据鉴别信息的提取和数据空间维度的压缩,以达到更高的聚类准确率。对滁菊花茶近红外光谱数据进行模糊C均值聚类(FCM)得到的模糊隶属度和聚类中心作为噪声鉴别C均值聚类(NDCM)的初始模糊隶属度和初始聚类中心,使NDCM具有聚类速度快,准确率高等优点。FCM算法对光谱噪声数据敏感,而NDCM算法在处理含噪声的光谱数据时能够表现出较好的性能。该研究选取特级滁菊、一级滁菊、二级滁菊三种品质等级的滁菊花茶作为实验样本,共计240个样本。实验使用便携式近红外光谱仪(NIR-M-F1-C)采集滁菊花茶的近红外光谱数据。用Savitzky-Golay滤波和多元散射校正(MSC)对滁菊花茶近红外光谱进行预处理,以减少光谱中掺杂的噪声和重叠信息。通过主成分分析(PCA)对采集到的400维光谱数据进行维度压缩降至6维。该研究使用线性判别分析(LDA)提取滁菊花茶光谱数据中的鉴别信息,并将数据空间维度进一步转换为2维。分别用FCM,FGNC和NDCM三种算法对处理后的数据进行聚类分析,以实现对滁菊花茶的准确分类。实验结果显示:当权重指数m=2.5时,FCM,FGNC,NDCM的聚类准确率分别为92.42%,98.48%,100%。NDCM聚类时间略长于FGNC。FCM算法需要进行27次迭代才能收敛,而FGNC算法和NDCM算法分别只需要13次和10次迭代就能达到收敛。采用近红外光谱技术结合MSC、Savitzky-Golay滤波、PCA、LDA和NDCM算法,建立了一种精准鉴别滁菊花茶品质等级的聚类模型。 展开更多
关键词 噪声鉴别C均值聚类 近红外光谱 无损检测 线性判别分析
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四级杆碰撞反应池-ICP-MS法测定维生素中铅、总砷、总汞含量的方法研究 被引量:1
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作者 潘煜辰 陈贵宇 周泽琳 《中国乳品工业》 CAS 北大核心 2024年第6期49-53,共5页
研究建立了四级杆碰撞反应池-ICP-MS法(Inductively coupled plasma mass spectrometry,ICP-MS)测定维生素及其预混料中铅、总砷和总汞的检测方法。样品加入硝酸,经微波消解后定容至100 m L,待测液采用四级杆碰撞反应池-ICP-MS法进行测... 研究建立了四级杆碰撞反应池-ICP-MS法(Inductively coupled plasma mass spectrometry,ICP-MS)测定维生素及其预混料中铅、总砷和总汞的检测方法。样品加入硝酸,经微波消解后定容至100 m L,待测液采用四级杆碰撞反应池-ICP-MS法进行测定。由于汞易挥发,实验中优化了消解的温度。维生素B_(12)样品中存在钴元素的干扰,以^(75)砷(As)和内标元素^(73)锗(Ge)的信号强度比值与砷元素的浓度成正比,采用碰撞反应池技术、氦气动能歧视(Kinetic energy discrimination,KED)模式进行定量分析,计算结果为样品中As和Co-O结合物的总含量;再以^(59)钴(Co)和内标元素^(45)钪(Sc)的信号强度比值与钴元素的浓度成正比,采用同样方法进行定量分析,得出钴的含量。最后通过计算两者之差得出样品中砷的含量。试验结果表明:铅、总砷和钴在1.0~50.0μg/L范围内线性关系良好,相关系数R均大于0.999。在不同加标水平下,3种元素的回收率范围在88.3%~104.3%之间,汞在0.1~2.0μg/L范围内线性关系良好,相关系数R为0.998。在不同加标水平下,汞元素的回收率范围在88.3%~104.3%之间,相对标准偏差(RSD)均小于10%。该方法操作简便、快速准确,适用于维生素及其预混料中铅、总砷、总汞元素的同时检测。 展开更多
关键词 维生素 电感耦合等离子体质谱 动能歧视 总砷 总汞
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