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Hyperspectral remote sensing identification of marine oil emulsions based on the fusion of spatial and spectral features
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作者 Xinyue Huang Yi Ma +1 位作者 Zongchen Jiang Junfang Yang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期139-154,共16页
Marine oil spill emulsions are difficult to recover,and the damage to the environment is not easy to eliminate.The use of remote sensing to accurately identify oil spill emulsions is highly important for the protectio... Marine oil spill emulsions are difficult to recover,and the damage to the environment is not easy to eliminate.The use of remote sensing to accurately identify oil spill emulsions is highly important for the protection of marine environments.However,the spectrum of oil emulsions changes due to different water content.Hyperspectral remote sensing and deep learning can use spectral and spatial information to identify different types of oil emulsions.Nonetheless,hyperspectral data can also cause information redundancy,reducing classification accuracy and efficiency,and even overfitting in machine learning models.To address these problems,an oil emulsion deep-learning identification model with spatial-spectral feature fusion is established,and feature bands that can distinguish between crude oil,seawater,water-in-oil emulsion(WO),and oil-in-water emulsion(OW)are filtered based on a standard deviation threshold–mutual information method.Using oil spill airborne hyperspectral data,we conducted identification experiments on oil emulsions in different background waters and under different spatial and temporal conditions,analyzed the transferability of the model,and explored the effects of feature band selection and spectral resolution on the identification of oil emulsions.The results show the following.(1)The standard deviation–mutual information feature selection method is able to effectively extract feature bands that can distinguish between WO,OW,oil slick,and seawater.The number of bands was reduced from 224 to 134 after feature selection on the Airborne Visible Infrared Imaging Spectrometer(AVIRIS)data and from 126 to 100 on the S185 data.(2)With feature selection,the overall accuracy and Kappa of the identification results for the training area are 91.80%and 0.86,respectively,improved by 2.62%and 0.04,and the overall accuracy and Kappa of the identification results for the migration area are 86.53%and 0.80,respectively,improved by 3.45%and 0.05.(3)The oil emulsion identification model has a certain degree of transferability and can effectively identify oil spill emulsions for AVIRIS data at different times and locations,with an overall accuracy of more than 80%,Kappa coefficient of more than 0.7,and F1 score of 0.75 or more for each category.(4)As the spectral resolution decreasing,the model yields different degrees of misclassification for areas with a mixed distribution of oil slick and seawater or mixed distribution of WO and OW.Based on the above experimental results,we demonstrate that the oil emulsion identification model with spatial–spectral feature fusion achieves a high accuracy rate in identifying oil emulsion using airborne hyperspectral data,and can be applied to images under different spatial and temporal conditions.Furthermore,we also elucidate the impact of factors such as spectral resolution and background water bodies on the identification process.These findings provide new reference for future endeavors in automated marine oil spill detection. 展开更多
关键词 oil emulsions identification hyperspectral remote sensing feature selection convolutional neural network(CNN) spatial-temporal transferability
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The study of intelligent algorithm in particle identification of heavy-ion collisions at low and intermediate energies
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作者 Gao-Yi Cheng Qian-Min Su +1 位作者 Xi-Guang Cao Guo-Qiang Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期170-182,共13页
Traditional particle identification methods face timeconsuming,experience-dependent,and poor repeatability challenges in heavy-ion collisions at low and intermediate energies.Researchers urgently need solutions to the... Traditional particle identification methods face timeconsuming,experience-dependent,and poor repeatability challenges in heavy-ion collisions at low and intermediate energies.Researchers urgently need solutions to the dilemma of traditional particle identification methods.This study explores the possibility of applying intelligent learning algorithms to the particle identification of heavy-ion collisions at low and intermediate energies.Multiple intelligent algorithms,including XgBoost and TabNet,were selected to test datasets from the neutron ion multi-detector for reaction-oriented dynamics(NIMROD-ISiS)and Geant4 simulation.Tree-based machine learning algorithms and deep learning algorithms e.g.TabNet show excellent performance and generalization ability.Adding additional data features besides energy deposition can improve the algorithm’s performance when the data distribution is nonuniform.Intelligent learning algorithms can be applied to solve the particle identification problem in heavy-ion collisions at low and intermediate energies. 展开更多
关键词 Heavy-ion collisions at low and intermediate energies Machine learning Ensemble learning algorithm Particle identification Data imbalance
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The Spatiotemporal Distribution Characteristics of Cloud Types and Phases in the Arctic Based on CloudSat and CALIPSO Cloud Classification Products
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作者 Yue SUN Huiling YANG +5 位作者 Hui XIAO Liang FENG Wei CHENG Libo ZHOU Weixi SHU Jingzhe SUN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期310-324,共15页
The cloud type product 2B-CLDCLASS-LIDAR based on CloudSat and CALIPSO from June 2006 to May 2017 is used to examine the temporal and spatial distribution characteristics and interannual variability of eight cloud typ... The cloud type product 2B-CLDCLASS-LIDAR based on CloudSat and CALIPSO from June 2006 to May 2017 is used to examine the temporal and spatial distribution characteristics and interannual variability of eight cloud types(high cloud, altostratus, altocumulus, stratus, stratocumulus, cumulus, nimbostratus, and deep convection) and three phases(ice,mixed, and water) in the Arctic. Possible reasons for the observed interannual variability are also discussed. The main conclusions are as follows:(1) More water clouds occur on the Atlantic side, and more ice clouds occur over continents.(2)The average spatial and seasonal distributions of cloud types show three patterns: high clouds and most cumuliform clouds are concentrated in low-latitude locations and peak in summer;altostratus and nimbostratus are concentrated over and around continents and are less abundant in summer;stratocumulus and stratus are concentrated near the inner Arctic and peak during spring and autumn.(3) Regional averaged interannual frequencies of ice clouds and altostratus clouds significantly decrease, while those of water clouds, altocumulus, and cumulus clouds increase significantly.(4) Significant features of the linear trends of cloud frequencies are mainly located over ocean areas.(5) The monthly water cloud frequency anomalies are positively correlated with air temperature in most of the troposphere, while those for ice clouds are negatively correlated.(6) The decrease in altostratus clouds is associated with the weakening of the Arctic front due to Arctic warming, while increased water vapor transport into the Arctic and higher atmospheric instability lead to more cumulus and altocumulus clouds. 展开更多
关键词 CloudSat and CALIPSO cloud type cloud phase temporal and spatial distribution interannual variation
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Identification of Microorganisms in Poultry Farms in N’djamena and the Border Areas of Hadjer-Lamis and Chari-Baguirmi Chad
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作者 Abakar Abbo Zakaria Bebanto Antipas Ban-Bo +2 位作者 Nadine Terei Bongo Naré Richard Gandolo Abdelsalam Adoum Doutoum 《Journal of Agricultural Chemistry and Environment》 2024年第2期223-234,共12页
Introduction: On the outskirts of Ndjamena, semi-industrial poultry farming and traditional poultry farming are practised informally on almost all poultry farms in Chad. This type of poultry farming is faced with real... Introduction: On the outskirts of Ndjamena, semi-industrial poultry farming and traditional poultry farming are practised informally on almost all poultry farms in Chad. This type of poultry farming is faced with real health problems attributable to a lack of monitoring of the vaccination schedule, inadequate compliance with biosecurity measures and poor application of the Ichikawa rule based on the 5 M’s. Objective: The aim of this article is to identify the microorganisms responsible for contamination of poultry farms in the study area. Method: The study was carried out from 28/04/2022 to 31/01/2023 on the basis of 300 samples taken from feed, drinking water, droppings and scrapings from poultry housing surfaces in the 30 farms that served as a framework for our research. Sampling was of the simple random type, and farms were selected on the basis of the farmers’ consent. The data were recorded on pre-established survey forms. Our study was cross-sectional, descriptive and prospective. Bacteria were isolated using the reference method NF EN ISO 6579 for Salmonella spp. and cultured on the specific medium eosin methylene blue (EMB) for Escherichia coli, Pseudomonas and Citrobacter freundii. Results: The following results emerged from this study: Escherichia coli (5.33%), Pseudomonas (1.33%), Citrobacter freundii (12%) and Salmonella paratyphi (21.68%). Conclusion: Of the 300 samples analysed, 121 (40.33%) were contaminated with pathogens. This high level of contamination is a health problem. The study shows that biosecurity is less satisfactory on the farms visited. Nevertheless, farms with a very satisfactory level of biosafety ensure food safety and variety for the population. 展开更多
关键词 Microorganisms identification Poultry Farms N’Djamena Hadjer-Lamis Chari-Baguirmi(Chad)
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The Moderating Effect of Organizational Identification on Occupational Stress and Insomnia Among Nurses
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作者 Jing Wang Haiyun Gai +3 位作者 Chunping Ni Juan Du Shanshan Li Huihui Yu 《Journal of Clinical and Nursing Research》 2024年第1期36-44,共9页
Objective:To explore the relationship between organizational identification,occupational stress,and insomnia among nurses and to analyze the moderating role of organizational identification between occupational stress... Objective:To explore the relationship between organizational identification,occupational stress,and insomnia among nurses and to analyze the moderating role of organizational identification between occupational stress and insomnia.Methods:Through stratified sampling,720 nurses working in a tertiary A-level hospital in Shandong Province from March to May 2021 were surveyed using an effort-reward imbalance questionnaire,an organizational identification questionnaire,and the Athens Insomnia scale.Results:Organizational identification was negatively correlated with occupational stress and insomnia(r_(1)=-0.121,P_(1)<0.01;r_(2)=-0.144,P_(2)<0.01).Occupational stress was positively correlated with insomnia(r=0.379,P<0.01).Organizational identity significantly moderated nurses’occupational stress and insomnia(β=-0.192,t=-2.558,P<0.05).Conclusion:Occupational stress and organizational identification can predict insomnia.Organizational identification could negatively mediate the relationship between occupational stress and insomnia.Improving organizational identification may help alleviate insomnia symptoms by relieving occupational stress. 展开更多
关键词 NURSE Occupational stress INSOMNIA Organizational identification Moderating effect
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Morphological and Molecular Identification of Fungi Associated with Sesame Diseased Plants of the Three Agroclimatic Zones of Burkina Faso
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作者 Wendolian Romain Soalla Pawindé Elisabeth Zida +1 位作者 Bouma James Neya Kadidia Koita 《American Journal of Plant Sciences》 CAS 2023年第3期290-307,共18页
Sesame is Burkina Faso’s second essential agricultural export after cotton. It’s consequently a supply of income for producers and foreign exchange for the country. However, sesame production is characterized by low... Sesame is Burkina Faso’s second essential agricultural export after cotton. It’s consequently a supply of income for producers and foreign exchange for the country. However, sesame production is characterized by low average yields of about 538 kg·ha<sup>-1</sup> at the farmer’s field as compared to the potential yield of the improved varieties (1500 - 2000 kg·ha<sup>-1</sup>). Fungal diseases are some of the major constraints to sesame production in Burkina Faso. The present study contributes to the development of means to control pathogenic fungi of this crop, which are responsible for significant losses. The objective is to identify the fungi associated with diseased sesame plant samples. To this end, 149 samples of diseased sesame plants were collected from different production sites located in three agro-climatic zones of the country. The analysis of the samples according to the blotting paper method, based on the morphological characteristics of the fungi, allowed the identification of 18 genera with prevalence rates from 2.68% to 97.98%. The most frequently identified genera were Macrophomina (97.98%), Cercospora (86.57%), Fusarium (85.23%), Phoma (62.41%) and Colletotrichum (61.07%). The results also showed a variable distribution of fungi according to the agro-climatic zone with the predominance of Macrophomina in all three zones. Molecular identification by DNA sequencing of 120 isolates belonging to the different fungi detected allowed the identification of 25 species of which the most representative were Macrophomina phaseolina, Cercospora sesami, Corynespora cassiicola, Alternaria simsimi, Alternaria porri, Fusarium oxysporum, F. fujikuroi, F. equiseti, Colletotrichum capsici, and C. gloesporiodes. The present study showed that diseased sesame plants collected from different production sites in Burkina Faso housed several species of fungi. The fungi presence in diseased plants indicates the need to inform and raise the stakeholders’ awareness about the phytosanitary problems of sesame, but also to develop effective and appropriate control methods against these crop pathogens in Burkina Faso. 展开更多
关键词 Burkina Faso FUNGI Molecular identification Morphological identification SEsame
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Pollution source identification methods and remediation technologies of groundwater: A review
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作者 Ya-ci Liu Yu-hong Fei +2 位作者 Ya-song Li Xi-lin Bao Peng-wei Zhang 《China Geology》 CAS CSCD 2024年第1期125-137,共13页
Groundwater is an important source of drinking water.Groundwater pollution severely endangers drinking water safety and sustainable social development.In the case of groundwater pollution,the top priority is to identi... Groundwater is an important source of drinking water.Groundwater pollution severely endangers drinking water safety and sustainable social development.In the case of groundwater pollution,the top priority is to identify pollution sources,and accurate information on pollution sources is the premise of efficient remediation.Then,an appropriate pollution remediation scheme should be developed according to information on pollution sources,site conditions,and economic costs.The methods for identifying pollution sources mainly include geophysical exploration,geochemistry,isotopic tracing,and numerical modeling.Among these identification methods,only the numerical modeling can recognize various information on pollution sources,while other methods can only identify a certain aspect of pollution sources.The remediation technologies of groundwater can be divided into in-situ and ex-situ remediation technologies according to the remediation location.The in-situ remediation technologies enjoy low costs and a wide remediation range,but their remediation performance is prone to be affected by environmental conditions and cause secondary pollution.The ex-situ remediation technologies boast high remediation efficiency,high processing capacity,and high treatment concentration but suffer high costs.Different methods for pollution source identification and remediation technologies are applicable to different conditions.To achieve the expected identification and remediation results,it is feasible to combine several methods and technologies according to the actual hydrogeological conditions of contaminated sites and the nature of pollutants.Additionally,detailed knowledge about the hydrogeological conditions and stratigraphic structure of the contaminated site is the basis of all work regardless of the adopted identification methods or remediation technologies. 展开更多
关键词 Groundwater pollution identification of pollution sources Geophysical exploration identification Geochemistry identification Isotopic tracing Numerical modeling Remediation technology Hydrogeological conditions Hydrogeological survey engineering
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In situ observation of the phase transformation kinetics of bismuth during shock release
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作者 李江涛 王倩男 +7 位作者 徐亮 柳雷 张航 Sota Takagi Kouhei Ichiyanagi Ryo Fukaya Shunsuke Nozawa 胡建波 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期586-592,共7页
A time-resolved x-ray diffraction technique is employed to monitor the structural transformation of laser-shocked bismuth.Results reveal a retarded transformation from the shock-induced Bi-Ⅴphase to a metastable Bi-... A time-resolved x-ray diffraction technique is employed to monitor the structural transformation of laser-shocked bismuth.Results reveal a retarded transformation from the shock-induced Bi-Ⅴphase to a metastable Bi-Ⅳphase during the shock release,instead of the thermodynamically stable Bi-Ⅲphase.The emergence of the metastable Bi-Ⅳphase is understood by the competitive interplay between two transformation pathways towards the Bi-Ⅳand Bi-Ⅲ,respectively.The former is more rapid than the latter because the Bi-Ⅴto B-Ⅳtransformation is driven by interaction between the closest atoms while the Bi-Ⅴto B-Ⅲtransformation requires interaction between the second-closest atoms.The nucleation time for the Bi-Ⅴto Bi-Ⅳtransformation is determined to be 5.1±0.9 ns according to a classical nucleation model.This observation demonstrates the importance of the formation of the transient metastable phases,which can change the phase transformation pathway in a dynamic process. 展开更多
关键词 phase transformation time-resolved x-ray diffraction(XRD) BISMUTH metastable phase nonequilibrium phase diagram
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Influence of Omega 3 Fatty Acid Supplementation on Phase Angle Values of People Living with HIV/AIDS with Lipodystrophy Secondary to Antiretroviral Therapy: A Randomized Clinical Trial
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作者 Thalita Bandeira Dantas Alline Peralta Castro +1 位作者 Fernando de Souza Flexa Ribeiro Filho Rosana Maria Feio Libonati 《Food and Nutrition Sciences》 CAS 2024年第1期58-70,共13页
Objective: The measurement of phase angles is an important monitoring parameter and supplementation with omega-3 could promote benefits by modulating the electrical potential of membranes and increasing body cell mass... Objective: The measurement of phase angles is an important monitoring parameter and supplementation with omega-3 could promote benefits by modulating the electrical potential of membranes and increasing body cell mass. This study aimed to evaluate the effectiveness of omega-3 fatty acid supplementation on the phase angle of people living with HIV/AIDS. Methods: In this study, 63 individuals of all genders who were undergoing outpatient follow-up and showed lipodystrophy due to highly active antiretroviral therapy were analyzed. Our sample consisted of two groups, one that received supplementation containing 2550 mg of omega-3/day (1080 mg of eicosapentaenoic acid and 720 mg of docosahexaenoic acid) for three months (n = 32) and another that underwent nutrition guidance (n = 31). Phase angle and body cell mass were assessed for both groups and compared at the beginning of research (T0) and after our intervention (T1) for each group separately. Results: Phase angle averaged 6.45° ± 1.06 SD. The comparison between T0 and T1 showed a significant increase in phase angle and body cell mass, whereas the guidance group showed a decrease in body cell mass at T1 in relation to T0, with a significant p-value. Variance in phase angle between moments showed significant values between T0 and T1 in the supplementation group for all genders. Conclusion: Omega-3 positively modulated patients phase angle and body cell mass, but we emphasize the need for other studies that can solidify knowledge about supplementation dosage and intervention time. 展开更多
关键词 HIV LIPODYSTROPHY Omega-3 Phase Angle
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Theory and verification of moiréfringes for x-ray three-phase grating interferometer
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作者 单雨征 葛永帅 +5 位作者 杨君 郭大育 蔡学宝 刘晓珂 侯晓文 郭金川 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期532-540,共9页
Dual-phase and three-phase grating x-ray interference is a promising new technique for grating-based x-ray differential phase contrast imaging.Dual-phase grating interferometers have been relatively completely studied... Dual-phase and three-phase grating x-ray interference is a promising new technique for grating-based x-ray differential phase contrast imaging.Dual-phase grating interferometers have been relatively completely studied and discussed.In this paper,the corresponding imaging fringe formula of the three-phase grating interferometer is provided.At the same time,the similarities and differences between the three-phase grating interferometer and the dual-phase grating interferometer are investigated and verified,and that the three-phase grating interferometer can produce large-period moiréfringes without using the analyzing grating is demonstrated experimentally.Finally,a simple method of designing three-phase grating and multi-grating imaging systems from geometric optics based on the thin-lens theory of gratings is presented.These theoretical formulas and experimental results provide optimization tools for designing three-phase grating interferometer systems. 展开更多
关键词 x-ray phase contrast phase grating moiréfringe
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Quaternion-Based Adaptive Trajectory Tracking Control of a Rotor-Missile with Unknown Parameters Identification
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作者 Jie Zhao Zhongjiao Shi +1 位作者 Yuchen Wang Wei Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期375-386,共12页
This paper investigates the adaptive trajectory tracking control problem and the unknown parameter identification problem of a class of rotor-missiles with parametric system uncertainties.First,considering the uncerta... This paper investigates the adaptive trajectory tracking control problem and the unknown parameter identification problem of a class of rotor-missiles with parametric system uncertainties.First,considering the uncertainty of structural and aerodynamic parameters,the six-degree-of-freedom(6Do F) nonlinear equations describing the position and attitude dynamics of the rotor-missile are established,respectively,in the inertial and body-fixed reference frames.Next,a hierarchical adaptive trajectory tracking controller that can guarantee closed-loop stability is proposed according to the cascade characteristics of the 6Do F dynamics.Then,a memory-augmented update rule of unknown parameters is proposed by integrating all historical data of the regression matrix.As long as the finitely excited condition is satisfied,the precise identification of unknown parameters can be achieved.Finally,the validity of the proposed trajectory tracking controller and the parameter identification method is proved through Lyapunov stability theory and numerical simulations. 展开更多
关键词 Rotor-missile Adaptive control Parameter identification Quaternion control
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Molecular Identification of Mycobacterium Strains Responsible of Bovine Tuberculosis Cases in Bobo-Dioulasso Slaughterhouse, Burkina Faso
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作者 Mariétou Konate Aminata Fofana# +2 位作者 Yacouba Kouadima Aboubacar Sidiki Ouattara Adama Sanou 《Advances in Microbiology》 CAS 2024年第2期105-114,共10页
Bovine tuberculosis (bTB) is an endemic zoonosis significantly affects animal health in Burkina Faso. The primary causative agent is Mycobacterium tuberculosis (M. tuberculosis) complex, mainly M. bovis. Cattle are co... Bovine tuberculosis (bTB) is an endemic zoonosis significantly affects animal health in Burkina Faso. The primary causative agent is Mycobacterium tuberculosis (M. tuberculosis) complex, mainly M. bovis. Cattle are considered as natural reservoir of M. bovis. However, in Burkina Faso, the circulation of these strains remains poorly understood and documented. This study aimed to identify and characterize Mycobacterium strains from suspected carcasses during routine meat inspection at Bobo-Dioulasso refrigerated slaughterhouse. A prospective cross-sectional study was conducted from January 2021 to December 2022 on cases of seizures linked to suspected bovine tuberculosis. Microbiological and molecular analyzes were used for mycobacterial strain isolation and characterization. Out of 50 samples, 24% tested positive by microscopy and 12% by culture. Molecular analysis identified 6 strains of Mycobacteria, exclusively Mycobacterium bovis specifically the subspecies bovis (Mycobacterium bovis subsp bovis). In conclusion, M. bovis subsp bovis is the primary agent responsible for bovine tuberculosis in Bobo-Dioulasso. Continuous monitoring of mycobacterial strains is therefore necessary for the effective control of this pathology in the local cattle population. 展开更多
关键词 Bovine Tuberculosis Mycobacterium bovis Molecular identification Cattle Population Burkina Faso
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Research on Risk Identification and Industrial Governance of Digital Education Products Based on Data Annotation Technology
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作者 Tong Lili Zeng Jia +1 位作者 Di Ying Wang Nan 《China Communications》 SCIE CSCD 2024年第3期273-282,共10页
The social transformation brought aboutby digital technology is deeply impacting various industries.Digital education products, with core technologiessuch as 5G, AI, IoT (Internet of Things),etc., are continuously pen... The social transformation brought aboutby digital technology is deeply impacting various industries.Digital education products, with core technologiessuch as 5G, AI, IoT (Internet of Things),etc., are continuously penetrating areas such as teaching,management, and evaluation. Apps, miniprograms,and emerging large-scale models are providingexcellent knowledge performance and flexiblecross-media output. However, they also exposerisks such as content discrimination and algorithmcommercialization. This paper conducts anevidence-based analysis of digital education productrisks from four dimensions: “digital resourcesinformationdissemination-algorithm design-cognitiveassessment”. It breaks through corresponding identificationtechnologies and, relying on the diverse characteristicsof governance systems, explores governancestrategies for digital education products from the threedomains of “regulators-developers-users”. 展开更多
关键词 digital education products industry governance risk identification
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Revealing the atomic mechanism of diamond–iron interfacial reaction
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作者 Yalun Ku Kun Xu +6 位作者 Longbin Yan Kuikui Zhang Dongsheng Song Xing Li Shunfang Li Shaobo Cheng Chongxin Shan 《Carbon Energy》 SCIE EI CAS CSCD 2024年第3期255-263,共9页
Diamond,with ultrahigh hardness,high wear resistance,high thermal conductivity,and so forth,has attracted worldwide attention.However,researchers found emergent reactions at the interfaces between diamond and ferrous ... Diamond,with ultrahigh hardness,high wear resistance,high thermal conductivity,and so forth,has attracted worldwide attention.However,researchers found emergent reactions at the interfaces between diamond and ferrous materials,which significantly affects the performance of diamond-based devices.Herein,combing experiments and theoretical calculations,taking diamond–iron(Fe)interface as a prototype,the counter-diffusion mechanism of Fe/carbon atoms has been established.Surprisingly,it is identified that Fe and diamond first form a coherent interface,and then Fe atoms diffuse into diamond and prefer the carbon vacancies sites.Meanwhile,the relaxed carbon atoms diffuse into the Fe lattice,forming Fe_(3)C.Moreover,graphite is observed at the Fe_(3)C surface when Fe_(3)C is over-saturated by carbon atoms.The present findings are expected to offer new insights into the atomic mechanism for diamondferrous material's interfacial reactions,benefiting diamond-based device applications. 展开更多
关键词 coherent interface counter-diffusion DIAMOND IRON phase transition
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Significantly enhanced thermal stability of HMX by phase-transition lysozyme coating
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作者 Jiahui Liu Congmei Lin +3 位作者 Jianhu Zhang Chengcheng Zeng Zhijian Yang Fude Nie 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期60-68,共9页
A new robust bio-inspired route by using lysozyme aqueous solution for surface modification on 1,3,5,7-tetranitro-1,3,5,7-tetrazocane(HMX)was described in this paper.HMX crystals were coated by in situ phase transitio... A new robust bio-inspired route by using lysozyme aqueous solution for surface modification on 1,3,5,7-tetranitro-1,3,5,7-tetrazocane(HMX)was described in this paper.HMX crystals were coated by in situ phase transition of lysozyme(PTL)molecules.The HMX decorated by PTL was characterized by SEM,XRD,FTIR and XPS,demonstrating a dense core-shell coating layer.The coverage of lysozyme on HMX crystal was calculated by the ratio of sulfur content.The surface coverage increased from 60.5% to 93.5% when the content of PTL was changed from 0.5 wt% to 2.0 wt%,indicating efficient coating.The thermal stability of HMX was investigated by in situ XRD and DSC.The thermal phase transition temperature of HMX(β to δ phase)was delayed by 42℃ with 2.0 wt% PTL coating,which prevented HMX from thermal damage and sensitivity by the effect of PTL coating.After heating at 215℃,large cracks appeared in the naked HMX crystal,while the PTL coated HMX still maintained intact,with the impact energy of HMX dropped dramatically from 5 J to 2 J.However,the impact energy of HMX with 1.0 wt% and 2.0 wt% coating content(HMX@PTL-1.0 and HMX@PTL-2.0)was unchanged(5 J).Present results potentially enable large-scale fabrication of polymorphic energetic materials with outstanding thermal stability by novel lysozyme coating. 展开更多
关键词 HMX LYSOZYME Phase transition thermal stability Sensitivity
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Novel method for identifying the stages of discharge underwater based on impedance change characteristic
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作者 高崇 康忠健 +3 位作者 龚大建 张扬 王玉芳 孙一鸣 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第4期133-145,共13页
It is difficult to determine the discharge stages in a fixed time of repetitive discharge underwater due to the arc formation process being susceptible to external environmental influences. This paper proposes a novel... It is difficult to determine the discharge stages in a fixed time of repetitive discharge underwater due to the arc formation process being susceptible to external environmental influences. This paper proposes a novel underwater discharge stage identification method based on the Strong Tracking Filter(STF) and impedance change characteristics. The time-varying equivalent circuit model of the discharge underwater is established based on the plasma theory analysis of the impedance change characteristics and mechanism of the discharge process. The STF is used to reduce the randomness of the impedance of repeated discharges underwater, and then the universal identification resistance data is obtained. Based on the resistance variation characteristics of the discriminating resistance of the pre-breakdown, main, and oscillatory discharge stages, the threshold values for determining the discharge stage are obtained. These include the threshold values for the resistance variation rate(K) and the moment(t).Experimental and error analysis results demonstrate the efficacy of this innovative method in discharge stage determination, with a maximum mean square deviation of Scrless than 1.761. 展开更多
关键词 discharge underwater discharge stage identification impedance characteristics strong tracking filter
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Phase-field lattice-Boltzmann study on fully coupled thermal-solute-convection dendrite growth of Al-Cu alloy
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作者 Yin-qi Qiu Meng-wu Wu +1 位作者 Xun-peng Qin Shou-mei Xiong 《China Foundry》 SCIE EI CAS CSCD 2024年第2期125-136,共12页
Dendrite growth is a complex liquid-solid phase transition process involving multiple physical factors.A phase-field lattice-Boltzmann method was developed to simulate the two-and three-dimension dendrite growth of Al... Dendrite growth is a complex liquid-solid phase transition process involving multiple physical factors.A phase-field lattice-Boltzmann method was developed to simulate the two-and three-dimension dendrite growth of Al-Cu alloy.The effect of fully coupled thermal-solute-convection interaction on the dendrite growth was investigated by incorporating a parallel-adaptive mesh refinement algorithm into the numerical model.By accurately reproducing the latent heat release,solute diffusion and convective transport behaviors at the liquidsolid interface,the interaction mechanism among thermal-solute-convection transport as well as their coupling effects on the dendrite growth dynamics were discussed.The simulation results show that the release of latent heat slows down the dendrite growth rate,and both natural and forced convection disrupt the symmetrical growth of dendrites.Their combination makes the growth of dendrites more complex,capturing important physical aspects such as recalescence,dendrite tip splitting,dendrite tilting,dendrite remelting,and solute plume in the simulation case.Based on the robustness and powerful ability of the numerical model,the formation mechanisms of these physical aspects were revealed. 展开更多
关键词 simulation phase field dendrite growth thermal-solute-convection interaction
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Coupling effect on the thermal hazard assessment of hazardous chemical materials via calorimetric technologies and simulation approaches
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作者 Yabei Xu Jiankun Shao +2 位作者 Wei Wang Shengliang Xu Dongping Chen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期644-654,共11页
The coupling effect of heat absorption and release exists in the thermal decomposition of a few chemical materials.However,the impact of the above coupling on thermal hazard assessment is not considered in the literat... The coupling effect of heat absorption and release exists in the thermal decomposition of a few chemical materials.However,the impact of the above coupling on thermal hazard assessment is not considered in the literature studies.In this work,nitroguanidine(NQ)and 1,3,5-trinitro-1,3,5-triazine(RDX)are selected as representative materials to explore the influence of the coupling effect on the thermal hazard assessment of chemical materials.The linear heating experiments of NQ and RDX are carried out by a microcalorimeter and synchronous thermal analyser.The thermal decomposition curves are decoupled by advanced thermokinetics software.The thermal decomposition and kinetic parameters before and after decoupling are calculated.The results of TG experiment show that both NQ and RDX began to lose mass during the endothermic stage.The endothermic melting and exothermic decomposition of NQ and RDX are coupled within this stage.The coupling effect has different degrees of influence on its initial decomposition temperature and safety parameters.Compared with the parameters in the coupling state,the initial decomposition temperature and adiabatic induction period after decoupling decrease.The self-accelerating decomposition temperature increases,and internal thermal runaway time decreases.In the thermal hazard assessment of chemical materials with coupling effects,the calculated parameters after decoupling should be taken as an important safety index。 展开更多
关键词 Calorimetric technologies KINETICS thermal hazard Phase transformation thermal decomposition
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Shock Raman spectra and structural transformation of powdered TKX-50 by the plate impact experiments combined with real-time Raman detection
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作者 Xue Yang Qijun Liu +3 位作者 Yundan Gan Lei Yang Zhengtang Liu Fusheng Liu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期158-162,共5页
As an energetic material of great interest,the work capacity of dihydroxylammonium 5,5’-bistetrazole-1,1’-diolate(TKX-50)has been questioned recently.Although some research groups have explored the reasons for the l... As an energetic material of great interest,the work capacity of dihydroxylammonium 5,5’-bistetrazole-1,1’-diolate(TKX-50)has been questioned recently.Although some research groups have explored the reasons for the low working ability of TKX-50,the plane impact experiment on powdered TKX-50 is obviously closer to the practical application,and the conclusions based on this are more guiding.Hence,we performed shock Hugoniot measurements of powdered TKX-50 between 5.65 and 16.29 GPa.The plane impact experiments of powdered TKX-50 were carried out and the shocked Raman spectra were collected.By Raman spectroscopy analysis,a new peak of powdered TKX-50 was found between19.47 GPa and 24.96 GPa,which may be caused by decomposition/phase transition and was related with the low work capacity. 展开更多
关键词 Powdered TKX-50 HUGONIOT RAMAN DECOMPOSITION Phase transition
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Relationship between Phenotypic Changes of Dendritic Cell Subsets and the Onset of Plateau Phase during Intermittent Interferon Therapy in Patients with CHB
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作者 YANG Liu WANG Shi Yu +13 位作者 JIANG Ting Ting DENG Wen CHANG Min WU Shu Ling CAO Wei Hua LU Yao SHEN Ge LIU Ru Yu GAO Yuan Jiao XU Meng Jiao HU Lei Ping ZHANG Lu XIE Yao LI Ming Hui 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第3期303-314,共12页
Objective This study aimed to evaluate whether the onset of the plateau phase of slow hepatitis B surface antigen decline in patients with chronic hepatitis B treated with intermittent interferon therapy is related to... Objective This study aimed to evaluate whether the onset of the plateau phase of slow hepatitis B surface antigen decline in patients with chronic hepatitis B treated with intermittent interferon therapy is related to the frequency of dendritic cell subsets and expression of the costimulatory molecules CD40,CD80,CD83,and CD86.Method This was a cross-sectional study in which patients were divided into a natural history group(namely NH group),a long-term oral nucleoside analogs treatment group(namely NA group),and a plateau-arriving group(namely P group).The percentage of plasmacytoid dendritic cell and myeloid dendritic cell subsets in peripheral blood lymphocytes and monocytes and the mean fluorescence intensity of their surface costimulatory molecules were detected using a flow cytometer.Results In total,143 patients were enrolled(NH group,n=49;NA group,n=47;P group,n=47).The results demonstrated that CD141/CD1c double negative myeloid dendritic cell(DNmDC)/lymphocytes and monocytes(%)in P group(0.041[0.024,0.069])was significantly lower than that in NH group(0.270[0.135,0.407])and NA group(0.273[0.150,0.443]),and CD86 mean fluorescence intensity of DNmDCs in P group(1832.0[1484.0,2793.0])was significantly lower than that in NH group(4316.0[2958.0,5169.0])and NA group(3299.0[2534.0,4371.0]),Adjusted P all<0.001.Conclusion Reduced DNmDCs and impaired maturation may be associated with the onset of the plateau phase during intermittent interferon therapy in patients with chronic hepatitis B. 展开更多
关键词 CHB Dendritic Cells Intermittent Interferon therapy Plateau Phase
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