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Detection of Turbulence Anomalies Using a Symbolic Classifier Algorithm in Airborne Quick Access Record(QAR)Data Analysis 被引量:1
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作者 Zibo ZHUANG Kunyun LIN +1 位作者 Hongying ZHANG Pak-Wai CHAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第7期1438-1449,共12页
As the risks associated with air turbulence are intensified by climate change and the growth of the aviation industry,it has become imperative to monitor and mitigate these threats to ensure civil aviation safety.The ... As the risks associated with air turbulence are intensified by climate change and the growth of the aviation industry,it has become imperative to monitor and mitigate these threats to ensure civil aviation safety.The eddy dissipation rate(EDR)has been established as the standard metric for quantifying turbulence in civil aviation.This study aims to explore a universally applicable symbolic classification approach based on genetic programming to detect turbulence anomalies using quick access recorder(QAR)data.The detection of atmospheric turbulence is approached as an anomaly detection problem.Comparative evaluations demonstrate that this approach performs on par with direct EDR calculation methods in identifying turbulence events.Moreover,comparisons with alternative machine learning techniques indicate that the proposed technique is the optimal methodology currently available.In summary,the use of symbolic classification via genetic programming enables accurate turbulence detection from QAR data,comparable to that with established EDR approaches and surpassing that achieved with machine learning algorithms.This finding highlights the potential of integrating symbolic classifiers into turbulence monitoring systems to enhance civil aviation safety amidst rising environmental and operational hazards. 展开更多
关键词 turbulence detection symbolic classifier quick access recorder data
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Data Masking for Chinese Electronic Medical Records with Named Entity Recognition 被引量:1
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作者 Tianyu He Xiaolong Xu +3 位作者 Zhichen Hu Qingzhan Zhao Jianguo Dai Fei Dai 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期3657-3673,共17页
With the rapid development of information technology,the electronifi-cation of medical records has gradually become a trend.In China,the population base is huge and the supporting medical institutions are numerous,so ... With the rapid development of information technology,the electronifi-cation of medical records has gradually become a trend.In China,the population base is huge and the supporting medical institutions are numerous,so this reality drives the conversion of paper medical records to electronic medical records.Electronic medical records are the basis for establishing a smart hospital and an important guarantee for achieving medical intelligence,and the massive amount of electronic medical record data is also an important data set for conducting research in the medical field.However,electronic medical records contain a large amount of private patient information,which must be desensitized before they are used as open resources.Therefore,to solve the above problems,data masking for Chinese electronic medical records with named entity recognition is proposed in this paper.Firstly,the text is vectorized to satisfy the required format of the model input.Secondly,since the input sentences may have a long or short length and the relationship between sentences in context is not negligible.To this end,a neural network model for named entity recognition based on bidirectional long short-term memory(BiLSTM)with conditional random fields(CRF)is constructed.Finally,the data masking operation is performed based on the named entity recog-nition results,mainly using regular expression filtering encryption and principal component analysis(PCA)word vector compression and replacement.In addi-tion,comparison experiments with the hidden markov model(HMM)model,LSTM-CRF model,and BiLSTM model are conducted in this paper.The experi-mental results show that the method used in this paper achieves 92.72%Accuracy,92.30%Recall,and 92.51%F1_score,which has higher accuracy compared with other models. 展开更多
关键词 Named entity recognition Chinese electronic medical records data masking principal component analysis regular expression
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Medi-Block Record Secure Data Sharing in Healthcare System:Issues,Solutions and Challenges
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作者 Zuriati Ahmad Zukarnain Amgad Muneer +1 位作者 Nur Atirah Mohamad Nassir Akram A。Almohammedi 《Computer Systems Science & Engineering》 SCIE EI 2023年第12期2725-2740,共16页
With the advancements in the era of artificial intelligence,blockchain,cloud computing,and big data,there is a need for secure,decentralized medical record storage and retrieval systems.While cloud storage solves stor... With the advancements in the era of artificial intelligence,blockchain,cloud computing,and big data,there is a need for secure,decentralized medical record storage and retrieval systems.While cloud storage solves storage issues,it is challenging to realize secure sharing of records over the network.Medi-block record in the healthcare system has brought a new digitalization method for patients’medical records.This centralized technology provides a symmetrical process between the hospital and doctors when patients urgently need to go to a different or nearby hospital.It enables electronic medical records to be available with the correct authentication and restricts access to medical data retrieval.Medi-block record is the consumer-centered healthcare data system that brings reliable and transparent datasets for the medical record.This study presents an extensive review of proposed solutions aiming to protect the privacy and integrity of medical data by securing data sharing for Medi-block records.It also aims to propose a comprehensive investigation of the recent advances in different methods of securing data sharing,such as using Blockchain technology,Access Control,Privacy-Preserving,Proxy Re-Encryption,and Service-On-Chain approach.Finally,we highlight the open issues and identify the challenges regarding secure data sharing for Medi-block records in the healthcare systems. 展开更多
关键词 Medi-block record healthcare system Blockchain technology secure data sharing
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Data Processing of Fault Recorder in Power System
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作者 Yu Qin Yu Bai Minghao Wen 《Energy and Power Engineering》 2017年第4期46-52,共7页
This article studies the fault recorder in power system and introduces the Comtrade format. Andituses C++ programming to read recorded fault data and adopts Fourier analysis and symmetrical component method to filter ... This article studies the fault recorder in power system and introduces the Comtrade format. Andituses C++ programming to read recorded fault data and adopts Fourier analysis and symmetrical component method to filter and extract fundamental waves. Finally the effectiveness of the data processing method introduced in this paper is verified by CAAP software. 展开更多
关键词 FAULT recorder READ and Process recordED FAULT data RESULT Verification
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Secure approach to sharing digitized medical data in a cloud environment
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作者 Kukatlapalli Pradeep Kumar Boppuru Rudra Prathap +2 位作者 Michael Moses Thiruthuvanathan Hari Murthy Vinay Jha Pillai 《Data Science and Management》 2024年第2期108-118,共11页
Without proper security mechanisms, medical records stored electronically can be accessed more easily than physical files. Patient health information is scattered throughout the hospital environment, including laborat... Without proper security mechanisms, medical records stored electronically can be accessed more easily than physical files. Patient health information is scattered throughout the hospital environment, including laboratories, pharmacies, and daily medical status reports. The electronic format of medical reports ensures that all information is available in a single place. However, it is difficult to store and manage large amounts of data. Dedicated servers and a data center are needed to store and manage patient data. However, self-managed data centers are expensive for hospitals. Storing data in a cloud is a cheaper alternative. The advantage of storing data in a cloud is that it can be retrieved anywhere and anytime using any device connected to the Internet. Therefore, doctors can easily access the medical history of a patient and diagnose diseases according to the context. It also helps prescribe the correct medicine to a patient in an appropriate way. The systematic storage of medical records could help reduce medical errors in hospitals. The challenge is to store medical records on a third-party cloud server while addressing privacy and security concerns. These servers are often semi-trusted. Thus, sensitive medical information must be protected. Open access to records and modifications performed on the information in those records may even cause patient fatalities. Patient-centric health-record security is a major concern. End-to-end file encryption before outsourcing data to a third-party cloud server ensures security. This paper presents a method that is a combination of the advanced encryption standard and the elliptical curve Diffie-Hellman method designed to increase the efficiency of medical record security for users. Comparisons of existing and proposed techniques are presented at the end of the article, with a focus on the analyzing the security approaches between the elliptic curve and secret-sharing methods. This study aims to provide a high level of security for patient health records. 展开更多
关键词 Electronic medical records Cloud computing data privacy Attribute-based encryption AUTHENTICATION
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Algorithms of mining data records from website automatically
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作者 邱勇 兰永杰 《Journal of Southeast University(English Edition)》 EI CAS 2006年第3期423-425,共3页
In order to improve the accuracy and integrality of mining data records from the web, the concepts of isomorphic page and directory page and three algorithms are proposed. An isomorphic web page is a set of web pages ... In order to improve the accuracy and integrality of mining data records from the web, the concepts of isomorphic page and directory page and three algorithms are proposed. An isomorphic web page is a set of web pages that have uniform structure, only differing in main information. A web page which contains many links that link to isomorphic web pages is called a directory page. Algorithm 1 can find directory web pages in a web using adjacent links similar analysis method. It first sorts the link, and then counts the links in each directory. If the count is greater than a given valve then finds the similar sub-page links in the directory and gives the results. A function for an isomorphic web page judgment is also proposed. Algorithm 2 can mine data records from an isomorphic page using a noise information filter. It is based on the fact that the noise information is the same in two isomorphic pages, only the main information is different. Algorithm 3 can mine data records from an entire website using the technology of spider. The experiment shows that the proposed algorithms can mine data records more intactly than the existing algorithms. Mining data records from isomorphic pages is an efficient method. 展开更多
关键词 data mining data record WEBSITE isomorphic page
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Digital Continuity Guarantee Approach of Electronic Record Based on Data Quality Theory 被引量:7
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作者 Yongjun Ren Jian Qi +2 位作者 Yaping Cheng Jin Wang Osama Alfarraj 《Computers, Materials & Continua》 SCIE EI 2020年第6期1471-1483,共13页
Since the British National Archive put forward the concept of the digital continuity in 2007,several developed countries have worked out their digital continuity action plan.However,the technologies of the digital con... Since the British National Archive put forward the concept of the digital continuity in 2007,several developed countries have worked out their digital continuity action plan.However,the technologies of the digital continuity guarantee are still lacked.At first,this paper analyzes the requirements of digital continuity guarantee for electronic record based on data quality theory,then points out the necessity of data quality guarantee for electronic record.Moreover,we convert the digital continuity guarantee of electronic record to ensure the consistency,completeness and timeliness of electronic record,and construct the first technology framework of the digital continuity guarantee for electronic record.Finally,the temporal functional dependencies technology is utilized to build the first integration method to insure the consistency,completeness and timeliness of electronic record. 展开更多
关键词 Electronic record digital continuity data quality
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Constructing Large Scale Cohort for Clinical Study on Heart Failure with Electronic Health Record in Regional Healthcare Platform:Challenges and Strategies in Data Reuse 被引量:2
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作者 Daowen Liu Liqi Lei +1 位作者 Tong Ruan Ping He 《Chinese Medical Sciences Journal》 CAS CSCD 2019年第2期90-102,共13页
Regional healthcare platforms collect clinical data from hospitals in specific areas for the purpose of healthcare management.It is a common requirement to reuse the data for clinical research.However,we have to face ... Regional healthcare platforms collect clinical data from hospitals in specific areas for the purpose of healthcare management.It is a common requirement to reuse the data for clinical research.However,we have to face challenges like the inconsistence of terminology in electronic health records (EHR) and the complexities in data quality and data formats in regional healthcare platform.In this paper,we propose methodology and process on constructing large scale cohorts which forms the basis of causality and comparative effectiveness relationship in epidemiology.We firstly constructed a Chinese terminology knowledge graph to deal with the diversity of vocabularies on regional platform.Secondly,we built special disease case repositories (i.e.,heart failure repository) that utilize the graph to search the related patients and to normalize the data.Based on the requirements of the clinical research which aimed to explore the effectiveness of taking statin on 180-days readmission in patients with heart failure,we built a large-scale retrospective cohort with 29647 cases of heart failure patients from the heart failure repository.After the propensity score matching,the study group (n=6346) and the control group (n=6346) with parallel clinical characteristics were acquired.Logistic regression analysis showed that taking statins had a negative correlation with 180-days readmission in heart failure patients.This paper presents the workflow and application example of big data mining based on regional EHR data. 展开更多
关键词 electronic health recordS CLINICAL terminology knowledge graph CLINICAL special disease case REPOSITORY evaluation of data quality large scale COHORT study
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Maintaining Consistency Based on Timely Updating Records List in Workflow Data
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作者 WU Hongli YIN Baolin ZHAO Xiao XIANG Gang 《Wuhan University Journal of Natural Sciences》 CAS 2008年第4期481-484,共4页
In order to settle the problem of workflow data consis-tency under the distributed environment, an invalidation strategy based-on timely updating record list is put forward. The strategy adopting the method of updatin... In order to settle the problem of workflow data consis-tency under the distributed environment, an invalidation strategy based-on timely updating record list is put forward. The strategy adopting the method of updating the records list and the recovery mechanism of updating message proves the classical invalidation strategy. When the request cycle of duplication is too long, the strategy uses the method of updating the records list to pause for sending updating message; when the long cycle duplication is requested again, it uses the recovery mechanism to resume the updating message. This strategy not only ensures the consistency of the workflow data, but also reduces the unnecessary network traffic. From theoretical comparison with those common strategies, the unnecessary network traffic of this strategy is fewer and more stable. The simulation results validate this conclusion. 展开更多
关键词 distributed environment workflow data records list update cycle threshold consistency maintenance
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Multi Attribute Case Based Privacy-preserving for Healthcare Transactional Data Using Cryptography 被引量:1
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作者 K.Saranya K.Premalatha 《Intelligent Automation & Soft Computing》 SCIE 2023年第2期2029-2042,共14页
Medical data mining has become an essential task in healthcare sector to secure the personal and medical data of patients using privacy policy.In this background,several authentication and accessibility issues emerge ... Medical data mining has become an essential task in healthcare sector to secure the personal and medical data of patients using privacy policy.In this background,several authentication and accessibility issues emerge with an inten-tion to protect the sensitive details of the patients over getting published in open domain.To solve this problem,Multi Attribute Case based Privacy Preservation(MACPP)technique is proposed in this study to enhance the security of privacy-preserving data.Private information can be any attribute information which is categorized as sensitive logs in a patient’s records.The semantic relation between transactional patient records and access rights is estimated based on the mean average value to distinguish sensitive and non-sensitive information.In addition to this,crypto hidden policy is also applied here to encrypt the sensitive data through symmetric standard key log verification that protects the personalized sensitive information.Further,linear integrity verification provides authentication rights to verify the data,improves the performance of privacy preserving techni-que against intruders and assures high security in healthcare setting. 展开更多
关键词 PRIVACY-PRESERVING crypto policy medical data mining integrity and verification personalized records CRYPTOGRAPHY
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Test Calibration of the Paleoclimatic Proxy Data with Chinese Historical Records
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作者 De'er Zhang 《Advances in Climate Change Research》 SCIE 2011年第1期38-42,共5页
The calibration of paleoclimate proxies is one of the key problems in the study of paleoclimate at present. Historical documentary records of climate are suitable for calibration on dating and the climatic implication... The calibration of paleoclimate proxies is one of the key problems in the study of paleoclimate at present. Historical documentary records of climate are suitable for calibration on dating and the climatic implication of the proxy data in a climatological sense. A test calibration on correcting the Delingha tree ring precipitation series using Chinese historical documentary records shows that among the 44 extreme dry cases in 1401 1950 AD, 42 cases (or 95.5%) are believable. Thus the long series of Delingha rings-denoted precipitation is highly reliable. Another test to validate the monsoon intensity proxy data based on the Zhanjiang Huguangyan sediments using historical records indicates that the years of Lake Maar Ti content series-designated winter monsoon intensities are entirely opposite to historical documents- depicted years of harsh winters in 800-900 AD. As a result, serious doubt is raised about the climatic implication of this paleo-monsoon proxy series. 展开更多
关键词 proxy data calibration PALEOCLIMATE historical documentary records of climate
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Design of universal data structure and interface based on dynamic self-incremental record
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作者 Yan Li Peng Ji 《International Journal of Technology Management》 2015年第3期115-116,共2页
In the software of data management system, there are some different lengths of records needed storing in an array, and the number of records often increases in use of the software. A universal data structure is presen... In the software of data management system, there are some different lengths of records needed storing in an array, and the number of records often increases in use of the software. A universal data structure is presented in the design, and it provide an unified interface for dynamic storage records in different length, so that the developers can call the unified interface directly for the data storage to simplify the design of data management system. 展开更多
关键词 data management system length-variable data record dynamic self-incremental array
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Guarantee Mechanism of Data Continuity for Electronic Record Based on Linked Data
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作者 Yuyi Huo Shi Zhou +2 位作者 Ruiguo Hu Yongjun Ren Jinyue Xia 《Journal of Cyber Security》 2020年第3期151-156,共6页
In the field of electronic record management,especially in the current big data environment,data continuity has become a new topic that is as important as security and needs to be studied.This paper decomposes the dat... In the field of electronic record management,especially in the current big data environment,data continuity has become a new topic that is as important as security and needs to be studied.This paper decomposes the data continuity guarantee of electronic record into a set of data protection requirements consisting of data relevance,traceability and comprehensibility,and proposes to use the associated data technology to provide an integrated guarantee mechanism to meet the above three requirements. 展开更多
关键词 Electronic record data continuity guarantee mechanism
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BC-PC-Share:Blockchain-Based Patient-Centric Data Sharing Scheme for PHRs in Cloud Computing
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作者 Caihui Lan Haifeng Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第9期2985-3010,共26页
Sharing of personal health records(PHR)in cloud computing is an essential functionality in the healthcare system.However,how to securely,efficiently and flexibly share PHRs data of the patient in a multi-receiver sett... Sharing of personal health records(PHR)in cloud computing is an essential functionality in the healthcare system.However,how to securely,efficiently and flexibly share PHRs data of the patient in a multi-receiver setting has not been well addressed.For instance,since the trust domain of the cloud server is not identical to the data owner or data user,the semi-trust cloud service provider may intentionally destroy or tamper shared PHRs data of user or only transform partial ciphertext of the shared PHRs or even return wrong computation results to save its storage and computation resource,to pursue maximum economic interest or other malicious purposes.Thus,the PHRs data storing or sharing via the cloud server should be performed with consistency and integrity verification.Fortunately,the emergence of blockchain technology provides new ideas and prospects for ensuring the consistency and integrity of shared PHRs data.To this end,in this work,we leverage the consortiumblockchain technology to enhance the trustworthiness of each participant and propose a blockchain-based patient-centric data sharing scheme for PHRs in cloud computing(BC-PC-Share).Different from the state-of-art schemes,our proposal can achieve the following desired properties:(1)Realizing patient-centric PHRs sharing with a public verification function,i.e.,which can ensure that the returned shared data is consistent with the requested shared data and the integrity of the shared data is not compromised.(2)Supporting scalable and fine-grained access control and sharing of PHRs data with multiple domain users,such as hospitals,medical research institutes,and medical insurance companies.(3)Achieving efficient user decryption by leveraging the transformation key technique and efficient user revocation by introducing time-controlled access.The security analysis and simulation experiment demonstrate that the proposed BC-PC-Share scheme is a feasible and promising solution for PHRs data sharing via consortium blockchain. 展开更多
关键词 Blockchain patient-centric personal health records data sharing attribute-based encryption
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Deletion and Recovery Scheme of Electronic Health Records Based onMedical Certificate Blockchain
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作者 Baowei Wang Neng Wang +2 位作者 Yuxiao Zhang Zenghui Xu Junhao Zhang 《Computers, Materials & Continua》 SCIE EI 2023年第7期849-859,共11页
The trusted sharing of Electronic Health Records(EHRs)can realize the efficient use of medical data resources.Generally speaking,EHRs are widely used in blockchain-based medical data platforms.EHRs are valuable privat... The trusted sharing of Electronic Health Records(EHRs)can realize the efficient use of medical data resources.Generally speaking,EHRs are widely used in blockchain-based medical data platforms.EHRs are valuable private assets of patients,and the ownership belongs to patients.While recent research has shown that patients can freely and effectively delete the EHRs stored in hospitals,it does not address the challenge of record sharing when patients revisit doctors.In order to solve this problem,this paper proposes a deletion and recovery scheme of EHRs based on Medical Certificate Blockchain.This paper uses cross-chain technology to connect the Medical Certificate Blockchain and the Hospital Blockchain to real-ize the recovery of deleted EHRs.At the same time,this paper uses the Medical Certificate Blockchain and the InterPlanetary File System(IPFS)to store Personal Health Records,which are generated by patients visiting different medical institutions.In addition,this paper also combines digital watermarking technology to ensure the authenticity of the restored electronic medical records.Under the combined effect of blockchain technology and digital watermarking,our proposal will not be affected by any other rights throughout the process.System analysis and security analysis illustrate the completeness and feasibility of the scheme. 展开更多
关键词 Electronic health records cross-chain medical certificate blockchain data deletion and recovery
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基于QAR数据的民机高高原进近着陆风险评估方法 被引量:3
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作者 陈农田 满永政 李俊辉 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2024年第1期77-85,共9页
民机高高原进近着陆是高原飞行高风险阶段。为有效实施高高原进近着陆风险识别和等级判据,提出基于熵权可变模糊识别的长短时记忆网络与深度神经网络(LSTM-DNN)相融合的深度学习风险评估方法。基于快速存取记录器(QAR)记录的高高原飞行... 民机高高原进近着陆是高原飞行高风险阶段。为有效实施高高原进近着陆风险识别和等级判据,提出基于熵权可变模糊识别的长短时记忆网络与深度神经网络(LSTM-DNN)相融合的深度学习风险评估方法。基于快速存取记录器(QAR)记录的高高原飞行数据,借鉴民机飞行品质监控(FOQA)咨询通告和行业QAR监控标准,结合指标重要度分析与Delphi专家调查,提取着陆时航向变化大、航迹低、610~305 m进近时下降率大、接地时垂直加速度及153~15 m进近时下降率大5个关键监控项目作为民机高高原进近着陆风险评估指标。为克服评估指标权重主观性偏差,应用熵权法确定评估指标权重,基于可变模糊识别方法构建风险等级隶属函数,建立基于LSTM-DNN的民机高高原进近着陆风险评估模型。以成都—拉萨进近着陆航段为例,提取QAR数据,对该风险评估模型进行训练与测试,并与Logistic多元回归、支持向量机(SVM)等评估方法进行比较,结果表明:所提方法平均准确率达到94.18%,最高可达94.79%,验证了方法的客观有效性。 展开更多
关键词 高高原飞行 快速存取记录器数据 熵权 可变模糊识别 LSTM-DNN深度学习 风险评估
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基于古今医案云平台探究中医治疗失眠的辨证思路及用药规律研究 被引量:1
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作者 李冬华 陈宗舜 左吉恒 《环球中医药》 CAS 2024年第7期1313-1319,共7页
目的运用古今医案云平台整理并分析中医治疗失眠的辨证思路及用药规律。方法收集古今医案云平台(V2.3.8)名医医案库中名老中医及其书籍中的医案数据,以古今医案云平台(V2.3.8)对用药频次、药味药性归经、舌象脉象等进行统计分析、聚类... 目的运用古今医案云平台整理并分析中医治疗失眠的辨证思路及用药规律。方法收集古今医案云平台(V2.3.8)名医医案库中名老中医及其书籍中的医案数据,以古今医案云平台(V2.3.8)对用药频次、药味药性归经、舌象脉象等进行统计分析、聚类分析、复杂网络分析。结果共纳入医案794个,涉及中药477味,主要有柴胡、白芍、甘草、酸枣仁、川芎、远志、赤芍、当归、合欢皮、茯苓、郁金、栀子。中药药性以平为主;药味多属甘、苦、辛;主要归肝经。高频中药系统聚类分析聚为4组,第一组:酸枣仁、茯苓;第二组:远志、合欢皮、郁金;第三组:白芍、栀子;第四组:柴胡、川芎、赤芍。药物关联分析得到:柴胡与白芍、柴胡与赤芍的关联性最强,其次是柴胡与川芎。复杂网络分析得到7组中医证候,从高到底依次为:肝阳上亢证,痰热扰心证,肝火扰心证,气滞血瘀证,心脾两虚证,肝肾阴虚证,肝郁气滞证。结论中医治疗失眠以清热助眠为法,平调阴阳为纲,多使用清热安神之品,值得临床参考运用。 展开更多
关键词 失眠 古今医案云平台 数据挖掘 用药规律 中医 医案
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在线数据记录和扰动观测器相结合的柔性机械臂复合学习控制
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作者 钱伟 徐海钦 +1 位作者 王霞 许斌 《控制理论与应用》 EI CAS CSCD 北大核心 2024年第8期1417-1426,共10页
本文针对多输入多输出的柔性机械臂动力学模型,提出了一种基于神经网络估计和扰动观测器的复合学习控制策略.首先,通过奇异摄动分析将系统解耦为快慢子系统.然后,针对慢变刚性子系统的动力学模型,基于在线数据记录模型构造新型预测误差... 本文针对多输入多输出的柔性机械臂动力学模型,提出了一种基于神经网络估计和扰动观测器的复合学习控制策略.首先,通过奇异摄动分析将系统解耦为快慢子系统.然后,针对慢变刚性子系统的动力学模型,基于在线数据记录模型构造新型预测误差,结合跟踪误差设计自适应控制律;针对快变柔性子系统采用滑模控制抑制弹性振动.在此基础上,构建了扰动观测器实时估计复合扰动信号,并纳入在线数据记录模型作为前馈补偿.最后,基于Lyapunov稳定性分析可证系统误差信号一致终值有界,仿真算例验证了所提策略的有效性和优越性. 展开更多
关键词 柔性机械臂 在线数据记录 扰动观测器 复合学习控制
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基于QAR着陆数据的跑道状况等级评估方法
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作者 谷润平 杨雪雅 +2 位作者 庄南剑 魏志强 卢飞 《安全与环境学报》 CAS CSCD 北大核心 2024年第6期2061-2067,共7页
跑道状况等级是飞机安全着陆的一个关键信息。为了进一步提高跑道状况评估的准确性和及时性,提出一种利用飞行快速存取记录器(Quick Access Recorder, QAR)数据快速评估跑道状况等级的方法。首先,根据飞行数据特征从繁多的数据中提取模... 跑道状况等级是飞机安全着陆的一个关键信息。为了进一步提高跑道状况评估的准确性和及时性,提出一种利用飞行快速存取记录器(Quick Access Recorder, QAR)数据快速评估跑道状况等级的方法。首先,根据飞行数据特征从繁多的数据中提取模型所需输入参数;其次,建立基于QAR数据建立飞机采用自动刹车着陆的动力学模型,并计算不同跑道状况等级对应的理论着陆距离;最后,将实际着陆距离与不同的跑道状况等级对应的理论着陆距离作对比,确定跑道状况等级。利用波音738和空客A320的QAR着陆数据分析某机场的跑道状况等级,并与该机场的雪情通告进行对比,验证了模型的准确性。研究成果可用于未来航班的着陆距离预测,为飞行员选择合适的刹车等级提供参考。 展开更多
关键词 安全工程 道面评估 快速存取记录器(QAR)数据 着陆性能 飞行动力学
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基于PLC+4G的病案库房远程巡查机器人研发
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作者 冯毅 许华忠 +1 位作者 冯钰宁 蓝宇 《科技创新与应用》 2024年第24期23-26,共4页
研发一款远程视频巡查库房中病案霉变痕迹、虫害痕迹及库房渗水痕迹的机器人。机器人采用四轮行走形式,2个后轮由2台步进电机分别驱动。机器人上安装垂直升降丝杆,其滑块上安装水平伸缩丝杆,一台筒形病案检查摄像机安装在水平丝杆滑块... 研发一款远程视频巡查库房中病案霉变痕迹、虫害痕迹及库房渗水痕迹的机器人。机器人采用四轮行走形式,2个后轮由2台步进电机分别驱动。机器人上安装垂直升降丝杆,其滑块上安装水平伸缩丝杆,一台筒形病案检查摄像机安装在水平丝杆滑块上,2根丝杆均由步进电机驱动,另有2台360°球形摄像机保证机器人行走无盲区。设计用户手机端HMI,点击HMI上按钮,通过物联网-4G-4G网关数据链向机器人上的PLC发出指令,控制机器人把病案检查摄像机移动到检查位置。3台摄像机视频通过另一条4G-物联网数据链传到用户电脑屏幕显示。实验验证远程控制系统及信号传输数据链切实可行,可在电脑上远程视频察看库房病案存储状况,确保病案安全。 展开更多
关键词 病案安全 PLC 机器人 物联网 数据链
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