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LLM-KE: An Ontology-Aware LLM Methodology for Military Domain Knowledge Extraction
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作者 Yu Tao Ruopeng Yang +3 位作者 Yongqi Wen Yihao Zhong Kaige Jiao Xiaolei Gu 《Computers, Materials & Continua》 2026年第1期2045-2061,共17页
Since Google introduced the concept of Knowledge Graphs(KGs)in 2012,their construction technologies have evolved into a comprehensive methodological framework encompassing knowledge acquisition,extraction,representati... Since Google introduced the concept of Knowledge Graphs(KGs)in 2012,their construction technologies have evolved into a comprehensive methodological framework encompassing knowledge acquisition,extraction,representation,modeling,fusion,computation,and storage.Within this framework,knowledge extraction,as the core component,directly determines KG quality.In military domains,traditional manual curation models face efficiency constraints due to data fragmentation,complex knowledge architectures,and confidentiality protocols.Meanwhile,crowdsourced ontology construction approaches from general domains prove non-transferable,while human-crafted ontologies struggle with generalization deficiencies.To address these challenges,this study proposes an OntologyAware LLM Methodology for Military Domain Knowledge Extraction(LLM-KE).This approach leverages the deep semantic comprehension capabilities of Large Language Models(LLMs)to simulate human experts’cognitive processes in crowdsourced ontology construction,enabling automated extraction of military textual knowledge.It concurrently enhances knowledge processing efficiency and improves KG completeness.Empirical analysis demonstrates that this method effectively resolves scalability and dynamic adaptation challenges in military KG construction,establishing a novel technological pathway for advancing military intelligence development. 展开更多
关键词 Knowledge extraction natural language processing knowledge graph large language model
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BEDiff:denoising diffusion probabilistic models for building extraction 被引量:1
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作者 LEI Yanjing WANG Yuan +3 位作者 CHAN Sixian HU Jie ZHOU Xiaolong ZHANG Hongkai 《Optoelectronics Letters》 2025年第5期298-305,共8页
Accurately identifying building distribution from remote sensing images with complex background information is challenging.The emergence of diffusion models has prompted the innovative idea of employing the reverse de... Accurately identifying building distribution from remote sensing images with complex background information is challenging.The emergence of diffusion models has prompted the innovative idea of employing the reverse denoising process to distill building distribution from these complex backgrounds.Building on this concept,we propose a novel framework,building extraction diffusion model(BEDiff),which meticulously refines the extraction of building footprints from remote sensing images in a stepwise fashion.Our approach begins with the design of booster guidance,a mechanism that extracts structural and semantic features from remote sensing images to serve as priors,thereby providing targeted guidance for the diffusion process.Additionally,we introduce a cross-feature fusion module(CFM)that bridges the semantic gap between different types of features,facilitating the integration of the attributes extracted by booster guidance into the diffusion process more effectively.Our proposed BEDiff marks the first application of diffusion models to the task of building extraction.Empirical evidence from extensive experiments on the Beijing building dataset demonstrates the superior performance of BEDiff,affirming its effectiveness and potential for enhancing the accuracy of building extraction in complex urban landscapes. 展开更多
关键词 booster guidance building extraction reverse denoising process diffusion model bediff which remote sensing images complex background diffusion models
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TIPS:Tailored Information Extraction in Public Security Using Domain-Enhanced Large Language Model
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作者 Yue Liu Qinglang Guo +1 位作者 Chunyao Yang Yong Liao 《Computers, Materials & Continua》 2025年第5期2555-2572,共18页
Processing police incident data in public security involves complex natural language processing(NLP)tasks,including information extraction.This data contains extensive entity information—such as people,locations,and ... Processing police incident data in public security involves complex natural language processing(NLP)tasks,including information extraction.This data contains extensive entity information—such as people,locations,and events—while also involving reasoning tasks like personnel classification,relationship judgment,and implicit inference.Moreover,utilizing models for extracting information from police incident data poses a significant challenge—data scarcity,which limits the effectiveness of traditional rule-based and machine-learning methods.To address these,we propose TIPS.In collaboration with public security experts,we used de-identified police incident data to create templates that enable large language models(LLMs)to populate data slots and generate simulated data,enhancing data density and diversity.We then designed schemas to efficiently manage complex extraction and reasoning tasks,constructing a high-quality dataset and fine-tuning multiple open-source LLMs.Experiments showed that the fine-tuned ChatGLM-4-9B model achieved an F1 score of 87.14%,nearly 30%higher than the base model,significantly reducing error rates.Manual corrections further improved performance by 9.39%.This study demonstrates that combining largescale pre-trained models with limited high-quality domain-specific data can greatly enhance information extraction in low-resource environments,offering a new approach for intelligent public security applications. 展开更多
关键词 Public security information extraction large language model prompt engineering
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AI-Driven Malware Detection with VGG Feature Extraction and Artificial Rabbits Optimized Random Forest Model
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作者 Brij B.Gupta Akshat Gaurav +3 位作者 Wadee Alhalabi Varsha Arya Shavi Bansal Ching-Hsien Hsu 《Computers, Materials & Continua》 2025年第9期4755-4772,共18页
Detecting cyber attacks in networks connected to the Internet of Things(IoT)is of utmost importance because of the growing vulnerabilities in the smart environment.Conventional models,such as Naive Bayes and support v... Detecting cyber attacks in networks connected to the Internet of Things(IoT)is of utmost importance because of the growing vulnerabilities in the smart environment.Conventional models,such as Naive Bayes and support vector machine(SVM),as well as ensemble methods,such as Gradient Boosting and eXtreme gradient boosting(XGBoost),are often plagued by high computational costs,which makes it challenging for them to perform real-time detection.In this regard,we suggested an attack detection approach that integrates Visual Geometry Group 16(VGG16),Artificial Rabbits Optimizer(ARO),and Random Forest Model to increase detection accuracy and operational efficiency in Internet of Things(IoT)networks.In the suggested model,the extraction of features from malware pictures was accomplished with the help of VGG16.The prediction process is carried out by the random forest model using the extracted features from the VGG16.Additionally,ARO is used to improve the hyper-parameters of the random forest model of the random forest.With an accuracy of 96.36%,the suggested model outperforms the standard models in terms of accuracy,F1-score,precision,and recall.The comparative research highlights our strategy’s success,which improves performance while maintaining a lower computational cost.This method is ideal for real-time applications,but it is effective. 展开更多
关键词 Malware detection VGG feature extraction artificial rabbits OPTIMIZATION random forest model
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Vector Extraction from Design Drawings for Intelligent 3D Modeling of Transmission Towers
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作者 Ziqiang Tang Chao Han +5 位作者 Hongwu Li Zhou Fan Ke Sun Yuntian Huang Yuhang Chen Chenxing Wang 《Computers, Materials & Continua》 2025年第2期2813-2829,共17页
Accurate vector extraction from design drawings is required first to automatically create 3D models from pixel-level engineering design drawings. However, this task faces the challenges of complicated design shapes as... Accurate vector extraction from design drawings is required first to automatically create 3D models from pixel-level engineering design drawings. However, this task faces the challenges of complicated design shapes as well as cumbersome and cluttered annotations on drawings, which interfere with the vector extraction heavily. In this article, the transmission tower containing the most complex structure is taken as the research object, and a semantic segmentation network is constructed to first segment the shape masks from the pixel-level drawings. Preprocessing and postprocessing are also proposed to ensure the stability and accuracy of the shape mask segmentation. Then, based on the obtained shape masks, a vector extraction network guided by heatmaps is designed to extract structural vectors by fusing the features from node heatmap and skeleton heatmap, respectively. Compared with the state-of-the-art methods, experiment results illustrate that the proposed semantic segmentation method can effectively eliminate the interference of many elements on drawings to segment the shape masks effectively, meanwhile, the model trained by the proposed vector extraction network can accurately extract the vectors such as nodes and line connections, avoiding redundant vector detection. The proposed method lays a solid foundation for automatic 3D model reconstruction and contributes to technological advancements in relevant fields. 展开更多
关键词 Design drawings semantic segmentation deep learning vector extraction DIGITIZATION 3D modeling
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Enhancing medical procurement information extraction with large language models: a prompt engineering approach
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作者 Zhi-Fei Tan Elaine Yen Nee Oon +1 位作者 Khin Wee Lai Xiang Wu 《Medical Data Mining》 2025年第2期31-47,共17页
Background:Acquiring relevant information about procurement targets is fundamental to procuring medical devices.Although traditional Natural Language Processing(NLP)and Machine Learning(ML)methods have improved inform... Background:Acquiring relevant information about procurement targets is fundamental to procuring medical devices.Although traditional Natural Language Processing(NLP)and Machine Learning(ML)methods have improved information retrieval efficiency to a certain extent,they exhibit significant limitations in adaptability and accuracy when dealing with procurement documents characterized by diverse formats and a high degree of unstructured content.The emergence of Large Language Models(LLMs)offers new possibilities for efficient procurement information processing and extraction.Methods:This study collected procurement transaction documents from public procurement websites,and proposed a procurement Information Extraction(IE)method based on LLMs.Unlike traditional approaches,this study systematically explores the applicability of LLMs in both structured and unstructured entities in procurement documents,addressing the challenges posed by format variability and content complexity.Furthermore,an optimized prompt framework tailored for procurement document extraction tasks is developed to enhance the accuracy and robustness of IE.The aim is to process and extract key information from medical device procurement quickly and accurately,meeting stakeholders'demands for precision and timeliness in information retrieval.Results:Experimental results demonstrate that,compared to traditional methods,the proposed approach achieves an F1 Score of 0.9698,representing a 4.85%improvement over the best baseline model.Moreover,both recall and precision rates are close to 97%,significantly outperforming other models and exhibiting exceptional overall recognition capabilities.Notably,further analysis reveals that the proposed method consistently maintains high performance across both structured and unstructured entities in procurement documents while balancing recall and precision effectively,demonstrating its adaptability in handling varying document formats.The results of ablation experiments validate the effectiveness of the proposed prompting strategy.Conclusion:Additionally,this study explores the challenges and potential improvements of the proposed method in IE tasks and provides insights into its feasibility for real-world deployment and application directions,further clarifying its adaptability and value.This method not only exhibits significant advantages in medical device procurement but also holds promise for providing new approaches to information processing and decision support in various domains. 展开更多
关键词 medical device procurement information extraction large language model
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Modified method for extraction of watershed boundary with digital elevation modeling 被引量:6
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作者 王殿中 郝占庆 熊在平 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第4期283-286,共4页
Boundary extraction of watershed is an important step in forest landscape research. The boundary of the upriver wa-tershed of the Hunhe River in the sub-alpine Qingyuan County of eastern Liaoning Province, China was e... Boundary extraction of watershed is an important step in forest landscape research. The boundary of the upriver wa-tershed of the Hunhe River in the sub-alpine Qingyuan County of eastern Liaoning Province, China was extracted by digital elevation modeling (DEM) data in ArcInfo8.1. Remote sensing image of the corresponding region was applied to help modify its copy according to Enhanced Thematic Mapper (ETM) image抯 profuse geomorphological structure information. Both the DEM-dependent boundary and modified copy were overlapped with county map and drainage network map to visually check the effects of result. Overlap of county map suggested a nice extraction of the boundary line since the two layers matched precisely, which indicated the DEM-dependent boundary by program was effective and precise. Further upload of drainage network showed discrepancies between the boundary and the drainage network. Altogether, there were three sections of the extraction result that needed to correct. Compared with this extraction boundary, the modified boundary had a better match to the drainage network as well as to the county map. Comprehensive analysis demonstrated that the program extraction has generally fine precision in position and excels the digitized result by hand. The errors of the DEM-dependant extraction are due to the fact that it is difficult for program to recognize sections of complex landform especially altered by human activities, but these errors are discernable and adjustable because the spatial resolution of ETM image is less than that of DEM. This study result proved that application of remote sensing information could help obtain better result when DEM method is used in extraction of watershed boundary. 展开更多
关键词 Forested watershed Boundary extraction Digital elevation modeling (DEM) Enhanced thematic mapper (ETM)
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Parameter Extraction for 2-π Equivalent Circuit Model of RF CMOS Spiral Inductors 被引量:1
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作者 高巍 余志平 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第4期667-673,共7页
A novel parameter extraction method with rational functions is presented for the 2-πequivalent circuit model of RF CMOS spiral inductors. The final S-parameters simulated by the circuit model closely match experiment... A novel parameter extraction method with rational functions is presented for the 2-πequivalent circuit model of RF CMOS spiral inductors. The final S-parameters simulated by the circuit model closely match experimental data. The extraction strategy is straightforward and can be easily implemented as a CAD tool to model spiral inductors. The resulting circuit models will be very useful for RF circuit designers. 展开更多
关键词 2-π compact model parameters extraction RF CMOS spiral inductors
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Auditory-model-based Feature Extraction Method for Mechanical Faults Diagnosis 被引量:12
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作者 LI Yungong ZHANG Jinping +2 位作者 DAI Li ZHANG Zhanyi LIU Jie 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第3期391-397,共7页
It is well known that the human auditory system possesses remarkable capabilities to analyze and identify signals. Therefore, it would be significant to build an auditory model based on the mechanism of human auditory... It is well known that the human auditory system possesses remarkable capabilities to analyze and identify signals. Therefore, it would be significant to build an auditory model based on the mechanism of human auditory systems, which may improve the effects of mechanical signal analysis and enrich the methods of mechanical faults features extraction. However the existing methods are all based on explicit senses of mathematics or physics, and have some shortages on distinguishing different faults, stability, and suppressing the disturbance noise, etc. For the purpose of improving the performances of the work of feature extraction, an auditory model, early auditory(EA) model, is introduced for the first time. This auditory model transforms time domain signal into auditory spectrum via bandpass filtering, nonlinear compressing, and lateral inhibiting by simulating the principle of the human auditory system. The EA model is developed with the Gammatone filterbank as the basilar membrane. According to the characteristics of vibration signals, a method is proposed for determining the parameter of inner hair cells model of EA model. The performance of EA model is evaluated through experiments on four rotor faults, including misalignment, rotor-to-stator rubbing, oil film whirl, and pedestal looseness. The results show that the auditory spectrum, output of EA model, can effectively distinguish different faults with satisfactory stability and has the ability to suppress the disturbance noise. Then, it is feasible to apply auditory model, as a new method, to the feature extraction for mechanical faults diagnosis with effect. 展开更多
关键词 faults diagnosis feature extraction auditory model early auditory model
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Small-signal modeling and parameter extraction method for a multigate GaAs pHEMT switch 被引量:4
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作者 Lin Luo Jun Liu +1 位作者 Guofang Wang Yuxing Wu 《Journal of Semiconductors》 EI CAS CSCD 2020年第3期7-12,共6页
This paper presents an accurate small-signal model for multi-gate GaAs pHEMTs in switching-mode.The extraction method for the proposed model is developed.A 2-gate switch structure is fabricated on a commercial 0.5μm ... This paper presents an accurate small-signal model for multi-gate GaAs pHEMTs in switching-mode.The extraction method for the proposed model is developed.A 2-gate switch structure is fabricated on a commercial 0.5μm AlGaAs/GaAs pHEMT technology to verify the proposed model.Excellent agreement has been obtained between the measured and simulated results over a wide frequency range. 展开更多
关键词 GaAs pHEMTs SWITCH small-signal model parameter extraction
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Ultrasonically Assisted Extraction of Isoflavones from Stem of Pueraria lobata (Willd.) Ohwi and Its Mathematical Model 被引量:16
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作者 徐化能 张颖心 何潮洪 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第6期861-867,共7页
Ultrasonically assisted extraction of isoflavones from the stem of Pueraria lobata (Willd.) Ohwi has been carried out with an ultrasonic extracting apparatus (20kHz, electrical power input to the transducer in 0-6... Ultrasonically assisted extraction of isoflavones from the stem of Pueraria lobata (Willd.) Ohwi has been carried out with an ultrasonic extracting apparatus (20kHz, electrical power input to the transducer in 0-650W). The influence of the electrical power input and extraction time on the'extraction yield is investigated in water, n-butanol, and 95% (by volume) and 50% (by volume) ethanol aqueous solution. The experimental results indicate that the yields of total isoflavones are higher in ultrasonically assisted extraction than those obtained from con-ventional extraction.Moreover,a mathematical model is proposed,by introducing the electrical power input to index the ultrsound intensity,to describe the behavior of ultrasonically assisted extraction.It is found that the model calcuations are in good agreement with the experimental data. 展开更多
关键词 ULTRASOUND mathematical model extraction Pueraria lobata (Willd.) Ohwi
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Extraction and Analysis of Gully Head of Loess Plateau in China Based on Digital Elevation Model 被引量:19
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作者 ZHU Hongchun TANG Guoan +1 位作者 QIAN Kejian LIU Haiying 《Chinese Geographical Science》 SCIE CSCD 2014年第3期328-338,共11页
In China′s Loess Plateau area, gully head is the most active zone of a drainage system in gully areas. The differentiation of loess gully head follows geospatial patterns and reflects the process of the loess landfor... In China′s Loess Plateau area, gully head is the most active zone of a drainage system in gully areas. The differentiation of loess gully head follows geospatial patterns and reflects the process of the loess landform development and evolution of its drainage system to some extent. In this study, the geomorphic meaning, basic characteristics, morphological structure and the basic types of loess gully heads were systematically analysed. Then, the loess gully head′s conceptual model was established, and an extraction method based on Digital Elevation Model(DEM) for loess gully head features and elements was proposed. Through analysing the achieved statistics of loess gully head features, loess gully heads have apparently similar and different characteristics depending on the different loess landforms where they are found. The loess head characteristics reflect their growth period and evolution tendency to a certain degree, and they indirectly represent evolutionary mechanisms. In addition, the loess gully developmental stages and the evolutionary processes can be deduced by using loess gully head characteristics. This study is of great significance for development and improvement of the theoretical system for describing loess gully landforms. 展开更多
关键词 Loess Plateau loess gully head Digital Elevation model (DEM) loess landform evolution feature extraction STATISTICALANALYSIS
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Experimental optimization and mathematical modeling of supercritical carbon dioxide extraction of essential oil from Pogostemon cablin 被引量:3
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作者 Kangning Xiong Yun Chen Shuai Shen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第10期2407-2417,共11页
The supercritical carbon dioxide extraction was applied to obtain essential oil from Pogostemon cablin in this work.Effect of extraction parameters including temperature,pressure,extraction time and particle size on e... The supercritical carbon dioxide extraction was applied to obtain essential oil from Pogostemon cablin in this work.Effect of extraction parameters including temperature,pressure,extraction time and particle size on extraction yield was investigated,and the response surface methodology with a Box–Behnken Design was used to achieve the optimized extraction conditions.The maximum yield of essential oil was 2.4356%under the conditions of extraction temperature 47°C,pressure 24.5 MPa and extraction time 119 min.Moreover,based on the Brunauer–Emmett–Teller theory of adsorption,a mathematical modeling was performed to correlate the measured data.The model shows a function relationship between extraction yield and time by a simple equation with three significantly adjustable parameters.These model parameters have been optimized through simulated annealing algorithm.The predicted data from the mathematical model show a good agreement with the experimental data of the different extraction parameters. 展开更多
关键词 SUPERCRITICAL carbon dioxide extraction Pogostemon cablin Response surface METHODOLOGY MATHEMATICAL modeling SIMULATED ANNEALING algorithm
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Modeling and Parameter Extraction of VDMOSFET
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作者 赖柯吉 张莉 田立林 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第3期251-256,共6页
A sub circuit model for VDMOS is built according to its physical structure.Parameters and formulas describing the device are also derived from this model.Comparing to former results,this model avoids too many technic... A sub circuit model for VDMOS is built according to its physical structure.Parameters and formulas describing the device are also derived from this model.Comparing to former results,this model avoids too many technical parameters and simplify the sub circuit efficiently.As a result of numeric computation,this simple model with clear physical conception demonstrates excellent agreements between measured and modeled response (DC error within 5%,AC error within 10%).Such a model is now available for circuit simulation and parameter extraction. 展开更多
关键词 vertical double diffused MOSFET parameter extraction sub circuit model JFET effect
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Component Content Soft-Sensor Based on Hybrid Models in Countercurrent Rare Earth Extraction Process 被引量:3
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作者 杨辉 王欣 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第S1期86-91,共6页
In consideration of the online measurement of the component content in rare earth countercurrent extraction separation process, the soft sensor method based on hybrid modeling was proposed to measure the rare earth co... In consideration of the online measurement of the component content in rare earth countercurrent extraction separation process, the soft sensor method based on hybrid modeling was proposed to measure the rare earth component content. The hybrid models were composed of the extraction equilibrium calculation model and the Radial Basis Function (RBF) Neural Network (NN) error compensation model; the parameters of compensation model were optimized by the hierarchical genetic algorithms (HGA). In addition, application experiment research of this proposed method was carried out in the rare earth separation production process of a corporation. The result shows that this method is effective and can realize online measurement for the component content of rare earth in the countercurrent extraction. 展开更多
关键词 countercurrent extraction soft-sensor equilibrium calculation model RBF neural networks hierarchical genetic algorithms rare earths
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Ontology-Based BERT Model for Automated Information Extraction from Geological Hazard Reports 被引量:5
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作者 Kai Ma Miao Tian +3 位作者 Yongjian Tan Qinjun Qiu Zhong Xie Rong Huang 《Journal of Earth Science》 SCIE CAS CSCD 2023年第5期1390-1405,共16页
Geological knowledge can provide support for knowledge discovery, knowledge inference and mineralization predictions of geological big data. Entity identification and relationship extraction from geological data descr... Geological knowledge can provide support for knowledge discovery, knowledge inference and mineralization predictions of geological big data. Entity identification and relationship extraction from geological data description text are the key links for constructing knowledge graphs. Given the lack of publicly annotated datasets in the geology domain, this paper illustrates the construction process of geological entity datasets, defines the types of entities and interconceptual relationships by using the geological entity concept system, and completes the construction of the geological corpus. To address the shortcomings of existing language models(such as Word2vec and Glove) that cannot solve polysemous words and have a poor ability to fuse contexts, we propose a geological named entity recognition and relationship extraction model jointly with Bidirectional Encoder Representation from Transformers(BERT) pretrained language model. To effectively represent the text features, we construct a BERT-bidirectional gated recurrent unit network(BiGRU)-conditional random field(CRF)-based architecture to extract the named entities and the BERT-BiGRU-Attention-based architecture to extract the entity relations. The results show that the F1-score of the BERT-BiGRU-CRF named entity recognition model is 0.91 and the F1-score of the BERT-BiGRU-Attention relationship extraction model is 0.84, which are significant performance improvements when compared to classic language models(e.g., word2vec and Embedding from Language Models(ELMo)). 展开更多
关键词 ONTOLOGY BERT model name entity recognition relation extraction knowledge graph
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STUDY ON GREY FORECASTING MODEL OF COPPER EXTRACTION RATE WITH BIOLEACHING OF PRIMARY SULFIDE ORE 被引量:2
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作者 A.X. Wu Y. Xi +2 位作者 B.H. Yang X.S. Chen H.C. Jiang 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2007年第2期117-128,共12页
A model GM (grey model) (1,1) for forecasting the rate of copper extraction during the bioleaching of primary sulphide ore was established on the basis of the mathematical theory and the modeling process of grey s... A model GM (grey model) (1,1) for forecasting the rate of copper extraction during the bioleaching of primary sulphide ore was established on the basis of the mathematical theory and the modeling process of grey system theory. It was used for forecasting the rate of copper extraction from the primary sulfide ore during a laboratory microbial column leaching experiment. The precision of the forecasted results were examined and modified via "posterior variance examination". The results show that the forecasted values coincide with the experimental values. GM (1,1) model has high forecast accuracy; and it is suitable for simulation control and prediction analysis of the original data series of the processes that have grey characteristics, such as mining, metallurgical and mineral processing, etc. The leaching rate of such copper sulphide ore is low. The grey forecasting result indicates that the rate of copper extraction is approximately 20% even after leaching for six months. 展开更多
关键词 primary copper sulfide ore BIOLEACHING extraction rate grey theory forecasting model
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Development of a predictive model for increasing sperm retrieval sucpess by microdissection testicular sperm extraction in patients with nonobstructive azoospermia 被引量:5
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作者 Chen-Yao Deng De-Feng Liu +8 位作者 Lian-Ming Zhao Hao-Cheng Lin Jia-Ming Mao Zhe Zhang Yu-Zhuo Yang Hai-Tao Zhang Kai Hong Hui-Yu Xu Hui Jiang 《Asian Journal of Andrology》 SCIE CAS CSCD 2023年第5期598-603,共6页
Microdissection testicular sperm extraction(micro-TESE)is widely used to treat nonobstructive azoospermia.However,a good prediction model is required to anticipate a successful sperm retrieval rate before performing m... Microdissection testicular sperm extraction(micro-TESE)is widely used to treat nonobstructive azoospermia.However,a good prediction model is required to anticipate a successful sperm retrieval rate before performing micro-TESE.This retrospective study analyzed the clinical records of 200 nonobstructive azoospermia patients between January 2021 and December 2021.The backward method was used to perform binary logistic regression analysis and identify factors that predicted a successful micro-TESE sperm retrieval.The prediction model was constructed using acquired regression coefficients,and its predictive performance was assessed using the receiver operating characteristic curve.In all,67 patients(sperm retrieval rate:33.5%)underwent successful micro-TESE.Follicle-stimulating hormone,anti-Miillerian hormone,and inhibin B levels varied significantly between patients who underwent successful and unsuccessful micro-TESE.Binary logistic regression analysis yielded the following six predictors:anti-Mullerian hormone(odds ratio[OR]=0.902,95%confidence interval[Cl]:0.821-0.990),inhibin B(OR=1.012,95%Cl:1.001-1.024),Klinefelter’s syndrome(OR=0.022,95%Cl:0.002-0.243),Y chromosome microdeletion(OR=0.050,95%Cl:0.005-0.504),cryptorchidism with orchiopexy(OR=0.085,95%Cl:0.008-0.929),and idiopathic nonobstructive azoospermia(OR=0.031,95%Cl:0.003-0.277).The prediction model had an area under the curve of 0.720(95%Cl:0.645-0.794),sensitivity of 65.7%,specificity of 72.2%,Youden index of 0.379,and cut-off value of 0.305 overall,indicating good predictive value and accuracy.This model can assist clinicians and nonobstructive azoospermia patients in decision-making and avoiding negative micro-TESE results. 展开更多
关键词 anti-Mullerian hormone inhibin B microdissection testicular sperm extraction predictive model sperm retrieval
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Adaptive WNN aerodynamic modeling based on subset KPCA feature extraction 被引量:5
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作者 孟月波 邹建华 +1 位作者 甘旭升 刘光辉 《Journal of Central South University》 SCIE EI CAS 2013年第4期931-941,共11页
In order to accurately describe the dynamic characteristics of flight vehicles through aerodynamic modeling, an adaptive wavelet neural network (AWNN) aerodynamic modeling method is proposed, based on subset kernel pr... In order to accurately describe the dynamic characteristics of flight vehicles through aerodynamic modeling, an adaptive wavelet neural network (AWNN) aerodynamic modeling method is proposed, based on subset kernel principal components analysis (SKPCA) feature extraction. Firstly, by fuzzy C-means clustering, some samples are selected from the training sample set to constitute a sample subset. Then, the obtained samples subset is used to execute SKPCA for extracting basic features of the training samples. Finally, using the extracted basic features, the AWNN aerodynamic model is established. The experimental results show that, in 50 times repetitive modeling, the modeling ability of the method proposed is better than that of other six methods. It only needs about half the modeling time of KPCA-AWNN under a close prediction accuracy, and can easily determine the model parameters. This enables it to be effective and feasible to construct the aerodynamic modeling for flight vehicles. 展开更多
关键词 WAVELET neural network fuzzy C-means clustering kernel principal components analysis feature extraction aerodynamic modeling
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Comparison of the Reynolds-averaged Turbulence Models on Single Phase Flow Simulation in Agitated Extraction Columns 被引量:4
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作者 尤学一 H.J.Bart 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第3期362-366,共5页
The flow field of liquid phase (water) of agitated extraction columns is simulated with the help of computational fluid dynamics (CFD). Four kinds of Reynolds-averaged turbulence models, i.e. the standard k-ε model, ... The flow field of liquid phase (water) of agitated extraction columns is simulated with the help of computational fluid dynamics (CFD). Four kinds of Reynolds-averaged turbulence models, i.e. the standard k-ε model, the RNG (renormalization group) k-s model, the realizable k-ε model and the Reynolds stress model, are compared in detail in order to judge which is the best model in terms of the accuracy, less CPU time and memory required. The performance of the realizable k-s model is obviously improved by reducing the model constant from C2 = 1.90 to C2 = 1.61. It is concluded that the improved realizable k-e model is the optimal model. 展开更多
关键词 agitated extraction column turbulence models computational fluid dynamics
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