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Standardization of meibomian gland dysfunction in an Egyptian population sample using a non-contact meibography technique
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作者 Ahmed Mohamed Karara Zeinab El-Sanabary +2 位作者 Mostafa Ali El-Helw Tamer Ahmed Macky Mohamad Amr Salah Eddin Abdelhakim 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第1期61-65,共5页
AIM:To develop normative data for meibomian gland dysfunction(MGD)parameters,using non-contact meibography technique of Sirius Costruzione Strumenti Oftalmici(CSO)machine,in an Egyptian population sample.METHODS:Obser... AIM:To develop normative data for meibomian gland dysfunction(MGD)parameters,using non-contact meibography technique of Sirius Costruzione Strumenti Oftalmici(CSO)machine,in an Egyptian population sample.METHODS:Observational,cross-sectional,analytic study,in which 104 Egyptian volunteers were included.Both upper lids were examined,using“Sirius CSO”machine.Each eyelid was given a degree of meibomian gland loss(MGL),which was calculated by the software of the machine.RESULTS:Mean percentage MGL in right upper lid was of 30.9%±12.6%,and that of left upper lid was 32.6%±11.8%.Thirty-four volunteers(32.7%)had first-degree MGL in their right upper lid,and 67.3%had second-degree loss.One volunteer(1%)had zero-degree MGL in left upper lid,28(26.9%)had first-degree loss,and 75(72.1%)had second-degree loss.Degree of MGL in right upper eyelid was not related to age,but degree of MGL in left upper eyelid increased with age.There was statistically significant difference between both genders for degree of MGL in right eye(P=0.036)and in left eye(P=0.027).CONCLUSION:Noncontact meibography is a useful non-invasive tool for diagnosing MGL.MGL is diagnosed in 100%of apparently normal individuals;26.9%-32.7%of which have first-degree MGL,and 67.3%-72.1%have second-degree MGL. 展开更多
关键词 Egyptian population meibomian gland dysfunction non-contact meibography STANDARDIZATION upper lid
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Non-contact wide-field viewing system-assisted scleral buckling surgery for retinal detachment in silicone oilfilled eyes
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作者 Su-Lan Wu Yi-Qi Chen +7 位作者 Li-Jun Shen Jian-Bo Mao Li Lin Ji-Wei Tao Huan Chen Shi-An Zhang Jia-Feng Yu Chen-Xi Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第4期761-766,共6页
AIM:To evaluate scleral buckling(SB)surgery using a noncontact wide-field viewing system and 23-gauge intraocular illumination for the treatment of rhegmatogenous retinal detachment in silicone oil(SO)-filled eyes.MET... AIM:To evaluate scleral buckling(SB)surgery using a noncontact wide-field viewing system and 23-gauge intraocular illumination for the treatment of rhegmatogenous retinal detachment in silicone oil(SO)-filled eyes.METHODS:Totally 9 patients(9 eyes)with retinal detachment in SO-filled eyes were retrospectively analyzed.All patients underwent non-contact wide-field viewing system-assisted buckling surgery with 23-gauge intraocular illumination.SO was removed at an appropriate time based on recovery.The patients were followed up for at least 3mo after SO removal.Retinal reattachment,complications,visual acuity and intraocular pressure(IOP)before and after surgery were observed.RESULTS:Patients were followed up for a mean of 8.22mo(3-22mo)after SO removal.All patients had retinal reattachment.At the final follow-up,visual acuity showed improvement for 8 patients,and no change for 1 patient.The IOP was high in 3 patients before surgery,but it stabilized after treatment;it was not affected in the other patients.None of the patients had infections,hemorrhage,anterior ischemia,or any other complication.CONCLUSION:This new non-contact wide-field viewing system-assisted SB surgery with 23-gauge intraocular illumination is effective and safe for retinal detachment in SO-filled eyes. 展开更多
关键词 non-contact wide-field viewing system scleral buckling silicone oil-filled retinal detachment
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Image Recognition Model of Fraudulent Websites Based on Image Leader Decision and Inception-V3 Transfer Learning
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作者 Shengli Zhou Cheng Xu +3 位作者 Rui Xu Weijie Ding Chao Chen Xiaoyang Xu 《China Communications》 SCIE CSCD 2024年第1期215-227,共13页
The fraudulent website image is a vital information carrier for telecom fraud.The efficient and precise recognition of fraudulent website images is critical to combating and dealing with fraudulent websites.Current re... The fraudulent website image is a vital information carrier for telecom fraud.The efficient and precise recognition of fraudulent website images is critical to combating and dealing with fraudulent websites.Current research on image recognition of fraudulent websites is mainly carried out at the level of image feature extraction and similarity study,which have such disadvantages as difficulty in obtaining image data,insufficient image analysis,and single identification types.This study develops a model based on the entropy method for image leader decision and Inception-v3 transfer learning to address these disadvantages.The data processing part of the model uses a breadth search crawler to capture the image data.Then,the information in the images is evaluated with the entropy method,image weights are assigned,and the image leader is selected.In model training and prediction,the transfer learning of the Inception-v3 model is introduced into image recognition of fraudulent websites.Using selected image leaders to train the model,multiple types of fraudulent websites are identified with high accuracy.The experiment proves that this model has a superior accuracy in recognizing images on fraudulent websites compared to other current models. 展开更多
关键词 fraudulent website image leaders telecom fraud transfer learning
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NFA:A neural factorization autoencoder based online telephony fraud detection
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作者 Abdul Wahid Mounira Msahli +1 位作者 Albert Bifet Gerard Memmi 《Digital Communications and Networks》 SCIE CSCD 2024年第1期158-167,共10页
The proliferation of internet communication channels has increased telecom fraud,causing billions of euros in losses for customers and the industry each year.Fraudsters constantly find new ways to engage in illegal ac... The proliferation of internet communication channels has increased telecom fraud,causing billions of euros in losses for customers and the industry each year.Fraudsters constantly find new ways to engage in illegal activity on the network.To reduce these losses,a new fraud detection approach is required.Telecom fraud detection involves identifying a small number of fraudulent calls from a vast amount of call traffic.Developing an effective strategy to combat fraud has become challenging.Although much effort has been made to detect fraud,most existing methods are designed for batch processing,not real-time detection.To solve this problem,we propose an online fraud detection model using a Neural Factorization Autoencoder(NFA),which analyzes customer calling patterns to detect fraudulent calls.The model employs Neural Factorization Machines(NFM)and an Autoencoder(AE)to model calling patterns and a memory module to adapt to changing customer behaviour.We evaluate our approach on a large dataset of real-world call detail records and compare it with several state-of-the-art methods.Our results show that our approach outperforms the baselines,with an AUC of 91.06%,a TPR of 91.89%,an FPR of 14.76%,and an F1-score of 95.45%.These results demonstrate the effectiveness of our approach in detecting fraud in real-time and suggest that it can be a valuable tool for preventing fraud in telecommunications networks. 展开更多
关键词 Telecom industry Streaming anomaly detection fraud analysis Factorization machine Real-time system Security
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Credit Card Fraud Detection Using Improved Deep Learning Models
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作者 Sumaya S.Sulaiman Ibraheem Nadher Sarab M.Hameed 《Computers, Materials & Continua》 SCIE EI 2024年第1期1049-1069,共21页
Fraud of credit cards is a major issue for financial organizations and individuals.As fraudulent actions become more complex,a demand for better fraud detection systems is rising.Deep learning approaches have shown pr... Fraud of credit cards is a major issue for financial organizations and individuals.As fraudulent actions become more complex,a demand for better fraud detection systems is rising.Deep learning approaches have shown promise in several fields,including detecting credit card fraud.However,the efficacy of these models is heavily dependent on the careful selection of appropriate hyperparameters.This paper introduces models that integrate deep learning models with hyperparameter tuning techniques to learn the patterns and relationships within credit card transaction data,thereby improving fraud detection.Three deep learning models:AutoEncoder(AE),Convolution Neural Network(CNN),and Long Short-Term Memory(LSTM)are proposed to investigate how hyperparameter adjustment impacts the efficacy of deep learning models used to identify credit card fraud.The experiments conducted on a European credit card fraud dataset using different hyperparameters and three deep learning models demonstrate that the proposed models achieve a tradeoff between detection rate and precision,leading these models to be effective in accurately predicting credit card fraud.The results demonstrate that LSTM significantly outperformed AE and CNN in terms of accuracy(99.2%),detection rate(93.3%),and area under the curve(96.3%).These proposed models have surpassed those of existing studies and are expected to make a significant contribution to the field of credit card fraud detection. 展开更多
关键词 Card fraud detection hyperparameter tuning deep learning autoencoder convolution neural network long short-term memory RESAMPLING
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Video-Based Deception Detection with Non-Contact Heart Rate Monitoring and Multi-Modal Feature Selection
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作者 Yanfeng Li Jincheng Bian +1 位作者 Yiqun Gao Rencheng Song 《Journal of Beijing Institute of Technology》 EI CAS 2024年第3期175-185,共11页
Deception detection plays a crucial role in criminal investigation.Videos contain a wealth of information regarding apparent and physiological changes in individuals,and thus can serve as an effective means of decepti... Deception detection plays a crucial role in criminal investigation.Videos contain a wealth of information regarding apparent and physiological changes in individuals,and thus can serve as an effective means of deception detection.In this paper,we investigate video-based deception detection considering both apparent visual features such as eye gaze,head pose and facial action unit(AU),and non-contact heart rate detected by remote photoplethysmography(rPPG)technique.Multiple wrapper-based feature selection methods combined with the K-nearest neighbor(KNN)and support vector machine(SVM)classifiers are employed to screen the most effective features for deception detection.We evaluate the performance of the proposed method on both a self-collected physiological-assisted visual deception detection(PV3D)dataset and a public bag-oflies(BOL)dataset.Experimental results demonstrate that the SVM classifier with symbiotic organisms search(SOS)feature selection yields the best overall performance,with an area under the curve(AUC)of 83.27%and accuracy(ACC)of 83.33%for PV3D,and an AUC of 71.18%and ACC of 70.33%for BOL.This demonstrates the stability and effectiveness of the proposed method in video-based deception detection tasks. 展开更多
关键词 deception detection apparent visual features remote photoplethysmography non-contact heart rate feature selection
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DC-FIPD: Fraudulent IP Identification Method Based on Homology Detection
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作者 Yuanyuan Ma Ang Chen +3 位作者 Cunzhi Hou Ruixia Jin Jinghui Zhang Ruixiang Li 《Computers, Materials & Continua》 SCIE EI 2024年第11期3301-3323,共23页
Currently,telecom fraud is expanding from the traditional telephone network to the Internet,and identifying fraudulent IPs is of great significance for reducing Internet telecom fraud and protecting consumer rights.Ho... Currently,telecom fraud is expanding from the traditional telephone network to the Internet,and identifying fraudulent IPs is of great significance for reducing Internet telecom fraud and protecting consumer rights.However,existing telecom fraud identification methods based on blacklists,reputation,content and behavioral characteristics have good identification performance in the telephone network,but it is difficult to apply to the Internet where IP(Internet Protocol)addresses change dynamically.To address this issue,we propose a fraudulent IP identification method based on homology detection and DBSCAN(Density-Based Spatial Clustering of Applications with Noise)clustering(DC-FIPD).First,we analyze the aggregation of fraudulent IP geographies and the homology of IP addresses.Next,the collected fraudulent IPs are clustered geographically to obtain the regional distribution of fraudulent IPs.Then,we constructed the fraudulent IP feature set,used the genetic optimization algorithm to determine the weights of the fraudulent IP features,and designed the calculation method of the IP risk value to give the risk value threshold of the fraudulent IP.Finally,the risk value of the target IP is calculated and the IP is identified based on the risk value threshold.Experimental results on a real-world telecom fraud detection dataset show that the DC-FIPD method achieves an average identification accuracy of 86.64%for fraudulent IPs.Additionally,the method records a precision of 86.08%,a recall of 45.24%,and an F1-score of 59.31%,offering a comprehensive evaluation of its performance in fraud detection.These results highlight the DC-FIPD method’s effectiveness in addressing the challenges of fraudulent IP identification. 展开更多
关键词 fraudulent IP identification homology detection CLUSTERING genetic optimization algorithm telecom fraud identification
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The Effects of Competence and Auditor Training on Fraud Detection Within Multinational Companies in Sub-Saharan Africa
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作者 Ivan Djossa Tchokoté Joëlle Tsobze Tiomeguim 《Journal of Modern Accounting and Auditing》 2024年第1期1-13,共13页
The aim of this study is to examine the qualities that auditors engaged in detecting potential fraud within multinational corporations in Sub-Saharan Africa should possess.To achieve this goal,a quantitative approach ... The aim of this study is to examine the qualities that auditors engaged in detecting potential fraud within multinational corporations in Sub-Saharan Africa should possess.To achieve this goal,a quantitative approach was used to develop and test a research model based on three theories:agency theory,attribution theory,and cognitive dissonance theory.Responses from a panel of two hundred and nine(209)auditors who conducted a legal audit mission in a Sub-Saharan multinational were analyzed using SmartPLS 3.3.3 software.The results emphasize the crucial importance of auditors’competence and continuous training in fraud detection.However,professional skepticism and time pressure were found to be non-significant in this context.This conclusion provides essential insights for auditors,highlighting the key qualities needed to effectively address fraud detection within multinational corporations in Sub-Saharan Africa. 展开更多
关键词 fraud legal audit fraud detection MULTINATIONALS Sub-Saharan Africa
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A Self-Adapting and Efficient Dandelion Algorithm and Its Application to Feature Selection for Credit Card Fraud Detection
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作者 Honghao Zhu MengChu Zhou +1 位作者 Yu Xie Aiiad Albeshri 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第2期377-390,共14页
A dandelion algorithm(DA) is a recently developed intelligent optimization algorithm for function optimization problems. Many of its parameters need to be set by experience in DA,which might not be appropriate for all... A dandelion algorithm(DA) is a recently developed intelligent optimization algorithm for function optimization problems. Many of its parameters need to be set by experience in DA,which might not be appropriate for all optimization problems. A self-adapting and efficient dandelion algorithm is proposed in this work to lower the number of DA's parameters and simplify DA's structure. Only the normal sowing operator is retained;while the other operators are discarded. An adaptive seeding radius strategy is designed for the core dandelion. The results show that the proposed algorithm achieves better performance on the standard test functions with less time consumption than its competitive peers. In addition, the proposed algorithm is applied to feature selection for credit card fraud detection(CCFD), and the results indicate that it can obtain higher classification and detection performance than the-state-of-the-art methods. 展开更多
关键词 Credit card fraud detection(CCFD) dandelion algorithm(DA) feature selection normal sowing operator
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An Anti-Fraud Policy:A Theoretical Framework for a Prosperity Tripod of Massive Data,Blockchain,and AI
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作者 Reza G.Hamzaee Maryam Salimi 《Management Studies》 2024年第2期102-123,共22页
The authors’aspiration was to learn-and focus on policy against fraud-leading to the sustainably growing societal illnesses of dishonesty,fraud,pessimism,and divisive issues.The appropriate venue,within the currently... The authors’aspiration was to learn-and focus on policy against fraud-leading to the sustainably growing societal illnesses of dishonesty,fraud,pessimism,and divisive issues.The appropriate venue,within the currently evolving laws and regulations,is proposed to be a three-tier combination of massive data,including data accumulation,transformation,organization,stratification,estimations,data analysis,and blockchain technology,predicted to revolutionize competition and efficiency,which are further suggested to be prerequisites for a more successful creation and implementation of the third element,AI.A currently evolving prosperity tripod is hinging on the three technological legs of the massive data control/management,blockchain tech,and a rapidly growing AI.While briefly incorporating some analysis of the blockchain application,we have analytically focused on the rest-the data and AI-of what we deem to be the prospective prosperity tripod for businesses,markets,and societies,in general,despite the challenges and risks involved in each.Instead of h ypothesizing a predetermined economic model,we are proposing a data-based Vector Autoregression(VAR)methodology for the AI with an application to the fraud and anti-fraud structure and policymaking.Hopefully,the entire attempt would portend some tangible prospective contribution in an achievable positive societal change. 展开更多
关键词 fraud AI data VAR
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Real-Time Fraud Detection Using Machine Learning
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作者 Benjamin Borketey 《Journal of Data Analysis and Information Processing》 2024年第2期189-209,共21页
Credit card fraud remains a significant challenge, with financial losses and consumer protection at stake. This study addresses the need for practical, real-time fraud detection methodologies. Using a Kaggle credit ca... Credit card fraud remains a significant challenge, with financial losses and consumer protection at stake. This study addresses the need for practical, real-time fraud detection methodologies. Using a Kaggle credit card dataset, I tackle class imbalance using the Synthetic Minority Oversampling Technique (SMOTE) to enhance modeling efficiency. I compare several machine learning algorithms, including Logistic Regression, Linear Discriminant Analysis, K-nearest Neighbors, Classification and Regression Tree, Naive Bayes, Support Vector, Random Forest, XGBoost, and Light Gradient-Boosting Machine to classify transactions as fraud or genuine. Rigorous evaluation metrics, such as AUC, PRAUC, F1, KS, Recall, and Precision, identify the Random Forest as the best performer in detecting fraudulent activities. The Random Forest model successfully identifies approximately 92% of transactions scoring 90 and above as fraudulent, equating to a detection rate of over 70% for all fraudulent transactions in the test dataset. Moreover, the model captures more than half of the fraud in each bin of the test dataset. SHAP values provide model explainability, with the SHAP summary plot highlighting the global importance of individual features, such as “V12” and “V14”. SHAP force plots offer local interpretability, revealing the impact of specific features on individual predictions. This study demonstrates the potential of machine learning, particularly the Random Forest model, for real-time credit card fraud detection, offering a promising approach to mitigate financial losses and protect consumers. 展开更多
关键词 Credit Card fraud Detection Machine Learning SHAP Values Random Forest
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Application Technologies and Challenges of Big Data Analytics in Anti-Money Laundering and Financial Fraud Detection
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作者 Haoran Jiang 《Open Journal of Applied Sciences》 2024年第11期3226-3236,共11页
As financial criminal methods become increasingly sophisticated, traditional anti-money laundering and fraud detection approaches face significant challenges. This study focuses on the application technologies and cha... As financial criminal methods become increasingly sophisticated, traditional anti-money laundering and fraud detection approaches face significant challenges. This study focuses on the application technologies and challenges of big data analytics in anti-money laundering and financial fraud detection. The research begins by outlining the evolutionary trends of financial crimes and highlighting the new characteristics of the big data era. Subsequently, it systematically analyzes the application of big data analytics technologies in this field, including machine learning, network analysis, and real-time stream processing. Through case studies, the research demonstrates how these technologies enhance the accuracy and efficiency of anomalous transaction detection. However, the study also identifies challenges faced by big data analytics, such as data quality issues, algorithmic bias, and privacy protection concerns. To address these challenges, the research proposes solutions from both technological and managerial perspectives, including the application of privacy-preserving technologies like federated learning. Finally, the study discusses the development prospects of Regulatory Technology (RegTech), emphasizing the importance of synergy between technological innovation and regulatory policies. This research provides guidance for financial institutions and regulatory bodies in optimizing their anti-money laundering and fraud detection strategies. 展开更多
关键词 Big Data Analytics Anti-Money Laundering Financial fraud Detection Machine Learning Regulatory Technology
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A LASER-SCANNING NON-CONTACT MEASURING METHOD FOR ROUNDNESS ERRORS 被引量:1
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作者 宋甲午 张国玉 +3 位作者 安志勇 李成志 景红薇 高玉军 《兵工学报》 EI CAS CSCD 北大核心 2000年第1期-,共3页
利用激光狭缝扫描原理和光电传感技术,提出了一种用于测量大型回转体类零件圆度误差的激光扫描非接触测量方法和测量系统。本文详细论述了测量系统及其测量原理、工件安装偏心误差的分离技术和计算机实时数据处理系统,实验结果证实了... 利用激光狭缝扫描原理和光电传感技术,提出了一种用于测量大型回转体类零件圆度误差的激光扫描非接触测量方法和测量系统。本文详细论述了测量系统及其测量原理、工件安装偏心误差的分离技术和计算机实时数据处理系统,实验结果证实了这种测量方法的可行性。 展开更多
关键词 圆度误差 激光狭缝扫描 非接触测量 偏心误差 A LASER-SCANNING non-contact MEASURING
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Credit Card Fraud Detection Using Weighted Support Vector Machine 被引量:3
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作者 Dongfang Zhang Basu Bhandari Dennis Black 《Applied Mathematics》 2020年第12期1275-1291,共17页
Credit card fraudulent data is highly imbalanced, and it has presented an overwhelmingly large portion of nonfraudulent transactions and a small portion of fraudulent transactions. The measures used to judge the verac... Credit card fraudulent data is highly imbalanced, and it has presented an overwhelmingly large portion of nonfraudulent transactions and a small portion of fraudulent transactions. The measures used to judge the veracity of the detection algorithms become critical to the deployment of a model that accurately scores fraudulent transactions taking into account case imbalance, and the cost of identifying a case as genuine when, in fact, the case is a fraudulent transaction. In this paper, a new criterion to judge classification algorithms, which considers the cost of misclassification, is proposed, and several undersampling techniques are compared by this new criterion. At the same time, a weighted support vector machine (SVM) algorithm considering the financial cost of misclassification is introduced, proving to be more practical for credit card fraud detection than traditional methodologies. This weighted SVM uses transaction balances as weights for fraudulent transactions, and a uniformed weight for nonfraudulent transactions. The results show this strategy greatly improve performance of credit card fraud detection. 展开更多
关键词 Support Vector Machine Binary Classification Imbalanced Data UNDERSAMPLING Credit Card fraud
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NON-CONTACT MEASUREMENT SYSTEM OF FREEFORM SURFACE AND NURBS RECONSTRUCTION OF MEASUREMENT POINTS 被引量:4
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作者 Li Jian Wang Wen Chen Zichen Institute of Advanced Manufacturing Engineering, Zhejiang University, Hangzhou 310027, China 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2002年第4期366-371,共6页
Based on the development of the non-contact measurement system of free-formsurface, NURBS reconstruction of measurement points of freeform surface is effectively realized bymodifying the objective function and recursi... Based on the development of the non-contact measurement system of free-formsurface, NURBS reconstruction of measurement points of freeform surface is effectively realized bymodifying the objective function and recursive procedure and calculating the optimum number ofcontrol points. The reconstruction precision is evaluated through Ja-cobi's transformation method.The feasibility of the measurement system and effectiveness of the reconstruction algorithm aboveare proved by experiment. 展开更多
关键词 freeform surface non-contact measurement NURBS precision evaluation
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Design of Non-contact On-load Automatic Regulating Voltage Transformer 被引量:5
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作者 Zhao Qi 《Journal of Northeast Agricultural University(English Edition)》 CAS 2015年第3期91-96,共6页
At present, an automatic-mechanic contact tap-changer is widely used in power system, but it can not frequently operate. In addition, arc will occur when the switch changes. In order to solve these two problems, this ... At present, an automatic-mechanic contact tap-changer is widely used in power system, but it can not frequently operate. In addition, arc will occur when the switch changes. In order to solve these two problems, this paper presented an automatic on-load voltage-regulating distributing transformer which employed non-contact solid-state relay as tap-changer, and mainly introduced its structure, basic principal, design method of each key link and experimental results. Laboratory simulation experiments informed that the scheme was feasible. It was a smooth and effective experiment device, which was practical in application. 展开更多
关键词 solid-state relay on-load tap-changer non-contact distributing transformer design
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Non-contact tensile viscoelastic characterization of microscale biological materials 被引量:3
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作者 Yuhui Li Yuan Hong +7 位作者 Guang-Kui Xu Shaobao Liu Qiang Shi Deding Tang Hui Yang Guy M.Genin Tian Jian Lu Feng Xu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2018年第3期589-599,共11页
Many structures and materials in nature and physiology have important "meso-scale" structures at the micron lengthscale whose tensile responses have proven difficult to characterize mechanically. Although techniques... Many structures and materials in nature and physiology have important "meso-scale" structures at the micron lengthscale whose tensile responses have proven difficult to characterize mechanically. Although techniques such as atomic force microscopy and micro- and nano-identation are mature for compression and indentation testing at the nano-scale, and standard uniaxial and shear rheometry techniques exist for the macroscale, few techniques are applicable for tensile-testing at the micrometre-scale, leaving a gap in our understanding of hierarchical biomaterials. Here, we present a novel magnetic mechanical testing (MMT) system that enables viscoelastic tensile testing at this critical length scale. The MMT system applies non-contact loading, avoiding gripping and surface interaction effects. We demonstrate application of the MMT system to the first analyses of the pure tensile responses of several native and engineered tissue systems at the mesoscale, showing the broad potential of the system for exploring micro- and meso-scale analysis of structured and hierarchical biological systems. 展开更多
关键词 Mechanical testing Hierarchical biomaterials non-contact actuation Microscale analysis
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Deep-Hole Inner Diameter Measuring System Based on Non-contact Capacitance Sensor 被引量:3
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作者 于永新 张恒 +1 位作者 王宗超 常以哲 《Transactions of Tianjin University》 EI CAS 2010年第6期447-451,共5页
A precise aperture measuring system of small deep holes with capacitance sensors is presented. Based on the working principle of non-contact capacitance sensors, influence of the edge effect of gauge head is studied, ... A precise aperture measuring system of small deep holes with capacitance sensors is presented. Based on the working principle of non-contact capacitance sensors, influence of the edge effect of gauge head is studied, and one capacitance sensor for measuring the aperture of the small blind holes or through holes is introduced. The system is composed of one positioning device, one aperture measuring capacitance sensor, one measuring circuit, and software. This system employs visual CCD and two-dimensional mic... 展开更多
关键词 deep-hole measurement non-contact CCD stepping motor precise positioning
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A Distributed Approach of Big Data Mining for Financial Fraud Detection in a Supply Chain 被引量:5
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作者 Hangjun Zhou Guang Sun +4 位作者 Sha Fu Xiaoping Fan Wangdong Jiang Shuting Hu Lingjiao Li 《Computers, Materials & Continua》 SCIE EI 2020年第8期1091-1105,共15页
Supply Chain Finance(SCF)is important for improving the effectiveness of supply chain capital operations and reducing the overall management cost of a supply chain.In recent years,with the deep integration of supply c... Supply Chain Finance(SCF)is important for improving the effectiveness of supply chain capital operations and reducing the overall management cost of a supply chain.In recent years,with the deep integration of supply chain and Internet,Big Data,Artificial Intelligence,Internet of Things,Blockchain,etc.,the efficiency of supply chain financial services can be greatly promoted through building more customized risk pricing models and conducting more rigorous investment decision-making processes.However,with the rapid development of new technologies,the SCF data has been massively increased and new financial fraud behaviors or patterns are becoming more covertly scattered among normal ones.The lack of enough capability to handle the big data volumes and mitigate the financial frauds may lead to huge losses in supply chains.In this article,a distributed approach of big data mining is proposed for financial fraud detection in a supply chain,which implements the distributed deep learning model of Convolutional Neural Network(CNN)on big data infrastructure of Apache Spark and Hadoop to speed up the processing of the large dataset in parallel and reduce the processing time significantly.By training and testing on the continually updated SCF dataset,the approach can intelligently and automatically classify the massive data samples and discover the fraudulent financing behaviors,so as to enhance the financial fraud detection with high precision and recall rates,and reduce the losses of frauds in a supply chain. 展开更多
关键词 Big data mining deep learning fraud detection supply chain Internet of Things
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Fraud detections for online businesses:a perspective from blockchain technology 被引量:2
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作者 Yuanfeng Cai Dan Zhu 《Financial Innovation》 2016年第1期256-265,共10页
Background:The reputation system has been designed as an effective mechanism to reduce risks associated with online shopping for customers.However,it is vulnerable to rating fraud.Some raters may inject unfairly high ... Background:The reputation system has been designed as an effective mechanism to reduce risks associated with online shopping for customers.However,it is vulnerable to rating fraud.Some raters may inject unfairly high or low ratings to the system so as to promote their own products or demote their competitors.Method:This study explores the rating fraud by differentiating the subjective fraud from objective fraud.Then it discusses the effectiveness of blockchain technology in objective fraud and its limitation in subjective fraud,especially the rating fraud.Lastly,it systematically analyzes the robustness of blockchain-based reputation systems in each type of rating fraud.Results:The detection of fraudulent raters is not easy since they can behave strategically to camouflage themselves.We explore the potential strengths and limitations of blockchain-based reputation systems under two attack goals:ballot-stuffing and bad-mouthing,and various attack models including constant attack,camouflage attack,whitewashing attack and sybil attack.Blockchain-based reputation systems are more robust against bad-mouthing than ballot-stuffing fraud.Conclusions:Blockchain technology provides new opportunities for redesigning the reputation system.Blockchain systems are very effective in preventing objective information fraud,such as loan application fraud,where fraudulent information is fact-based.However,their effectiveness is limited in subjective information fraud,such as rating fraud,where the ground-truth is not easily validated.Blockchain systems are effective in preventing bad mouthing and whitewashing attack,but they are limited in detecting ballot-stuffing under sybil attack,constant attacks and camouflage attack. 展开更多
关键词 Blockchain fraud detection Rating fraud Reputation systems
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