期刊文献+
共找到45篇文章
< 1 2 3 >
每页显示 20 50 100
Numerical analysis of the resonance mechanism of the lumped parameter system model for acoustic mine detection 被引量:2
1
作者 王驰 周瑜秋 +2 位作者 沈高炜 吴文雯 丁卫 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第12期308-314,共7页
The method of numerical analysis is employed to study the resonance mechanism of the lumped parameter system model for acoustic mine detection. Based on the basic principle of the acoustic resonance technique for mine... The method of numerical analysis is employed to study the resonance mechanism of the lumped parameter system model for acoustic mine detection. Based on the basic principle of the acoustic resonance technique for mine detection and the characteristics of low-frequency acoustics, the “soil-mine” system could be equivalent to a damping “mass-spring” resonance model with a lumped parameter analysis method. The dynamic simulation software, Adams, is adopted to analyze the lumped parameter system model numerically. The simulated resonance frequency and anti-resonance frequency are 151 Hz and 512 Hz respectively, basically in agreement with the published resonance frequency of 155 Hz and anti-resonance frequency of 513 Hz, which were measured in the experiment. Therefore, the technique of numerical simulation is validated to have the potential for analyzing the acoustic mine detection model quantitatively. The influences of the soil and mine parameters on the resonance characteristics of the soil–mine system could be investigated by changing the parameter setup in a flexible manner. 展开更多
关键词 acoustic mine detection acoustic–seismic coupling resonance model
原文传递
Establishment of an optimized CTC detection model consisting of EpCAM,MUC1 and WT1 in epithelial ovarian cancer and its correlation with clinical characteristics 被引量:9
2
作者 Tongxia Wang Yan Gao +9 位作者 Xi Wang Junrui Tian Yuan Li Bo Yu Cuiyu Huang Hui Li Huamao Liang David M.Irwin Huanran Tan Hongyan Guo 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2022年第2期95-108,共14页
Objective:Emerging studies have demonstrated the promising clinical value of circulating tumor cells(CTCs)for diagnosis,disease assessment,treatment monitoring and prognosis in epithelial ovarian cancer.However,the cl... Objective:Emerging studies have demonstrated the promising clinical value of circulating tumor cells(CTCs)for diagnosis,disease assessment,treatment monitoring and prognosis in epithelial ovarian cancer.However,the clinical application of CTC remains restricted due to diverse detection techniques with variable sensitivity and specificity and a lack of common standards.Methods:We enrolled 160 patients with epithelial ovarian cancer as the experimental group,and 90 patients including 50 patients with benign ovarian tumor and 40 healthy females as the control group.We enriched CTCs with immunomagnetic beads targeting two epithelial cell surface antigens(EpCAM and MUC1),and used multiple reverse transcription-polymerase chain reaction(RT-PCR)detecting three markers(EpCAM,MUC1 and WT1)for quantification.And then we used a binary logistic regression analysis and focused on EpCAM,MUC1 and WT1 to establish an optimized CTC detection model.Results:The sensitivity and specificity of the optimized model is 79.4%and 92.2%,respectively.The specificity of the CTC detection model is significantly higher than CA125(92.2%vs.82.2%,P=0.044),and the detection rate of CTCs was higher than the positive rate of CA125(74.5%vs.58.2%,P=0.069)in early-stage patients(stage I and II).The detection rate of CTCs was significantly higher in patients with ascitic volume≥500 mL,suboptimal cytoreductive surgery and elevated serum CA125 level after 2 courses of chemotherapy(P<0.05).The detection rate of CTC;and CTC;was significantly higher in chemo-resistant patients(26.3%vs.11.9%;26.4%vs.13.4%,P<0.05).The median progression-free survival time for CTC;patients trended to be longer than CTC;patients,and overall survival was shorter in CTC;patients(P=0.043).Conclusions:Our study presents an optimized detection model for CTCs,which consists of the expression levels of three markers(EpCAM,MUC1 and WT1).In comparison with CA125,our model has high specificity and demonstrates better diagnostic values,especially for early-stage ovarian cancer.Detection of CTC;and CTC;had predictive value for chemotherapy resistance,and the detection of CTC;suggested poor prognosis. 展开更多
关键词 Circulating tumor cells epithelial ovarian cancer optimized detection model diagnosis and prognosis
暂未订购
A Novel System for Moving Object Detection Using Bionic Compound Eyes 被引量:6
3
作者 Huabo Sun Haimeng Zhao +3 位作者 Peter Mooney Hongying Zhao Daping Liu Lei Yan 《Journal of Bionic Engineering》 SCIE EI CSCD 2011年第3期313-322,共10页
Conventional moving target detection focuses on algorithms to improve detection efficiency. These algorithms pay less attention to the image acquisition means, and usually solve specific problems. This often results i... Conventional moving target detection focuses on algorithms to improve detection efficiency. These algorithms pay less attention to the image acquisition means, and usually solve specific problems. This often results in poor flexibility and reus- ability. Insect compound eyes offer unique advantages for moving target detection and these advantages have attracted the attention of many researchers in recent years. In this paper we proposed a new system for moving target detection. We used the detection mechanism of insect compound eyes for the simulation of the characteristics of structure, control, and function. We discussed the design scheme of the system, the development of the bionic control circuit, and introduced the proposed mathe- matical model of bionic cqmpound eyes for data acquisition and object detection. After this the integrated system was described and discussed. Our paper presents a novel approach for moving target detection. This approach effectively tackles some of the well-known problems in the field of view, resolution, and real-time processing problems in moving target detection. 展开更多
关键词 moving target detection bionic compound eyes mechanical structure control circuit detection model
在线阅读 下载PDF
A Novel Shilling Attack Detection Model Based on Particle Filter and Gravitation 被引量:1
4
作者 Lingtao Qi Haiping Huang +2 位作者 Feng Li Reza Malekian Ruchuan Wang 《China Communications》 SCIE CSCD 2019年第10期112-132,共21页
With the rapid development of e-commerce, the security issues of collaborative filtering recommender systems have been widely investigated. Malicious users can benefit from injecting a great quantities of fake profile... With the rapid development of e-commerce, the security issues of collaborative filtering recommender systems have been widely investigated. Malicious users can benefit from injecting a great quantities of fake profiles into recommender systems to manipulate recommendation results. As one of the most important attack methods in recommender systems, the shilling attack has been paid considerable attention, especially to its model and the way to detect it. Among them, the loose version of Group Shilling Attack Generation Algorithm (GSAGenl) has outstanding performance. It can be immune to some PCC (Pearson Correlation Coefficient)-based detectors due to the nature of anti-Pearson correlation. In order to overcome the vulnerabilities caused by GSAGenl, a gravitation-based detection model (GBDM) is presented, integrated with a sophisticated gravitational detector and a decider. And meanwhile two new basic attributes and a particle filter algorithm are used for tracking prediction. And then, whether an attack occurs can be judged according to the law of universal gravitation in decision-making. The detection performances of GBDM, HHT-SVM, UnRAP, AP-UnRAP Semi-SAD,SVM-TIA and PCA-P are compared and evaluated. And simulation results show the effectiveness and availability of GBDM. 展开更多
关键词 shilling attack detection model collaborative filtering recommender systems gravitation-based detection model particle filter algorithm
在线阅读 下载PDF
Intrusion Detection Model Based on Incomplete Information Ga me in Wireless Mesh Networks 被引量:1
5
作者 Chen Jing Du Ruiying +2 位作者 Yu Fajiang Zheng Minghui Zhang Huanguo 《China Communications》 SCIE CSCD 2012年第10期23-32,共10页
Wireless Mesh Networks (WMNs) have many applications in homes, schools, enterprises, and public places because of their useful characteristics, such as high bandwidth, high speed, and wide coverage. However, the sec... Wireless Mesh Networks (WMNs) have many applications in homes, schools, enterprises, and public places because of their useful characteristics, such as high bandwidth, high speed, and wide coverage. However, the security of wireless mesh networks is a precondition for practical use. Intrusion detection is pivotal for increasing network security. Considering the energy limitations in wireless mesh networks, we adopt two types of nodes: Heavy Intrusion Detection Node (HIDN) and Light Intrusion Detection Node (LIDN). To conserve energy, the LIDN detects abnorrml behavior according to probability, while the HIDN, which has sufficient energy, is always operational. In practice, it is very difficult to acquire accurate information regarding attackers. We propose an intrusion detection model based on the incomplete inforrmtion game (ID-IIG). The ID-IIG utilizes the Harsanyi transformation and Bayesian Nash equilibrium to select the best strategies of defenders, although the exact attack probability is unknown. Thus, it can effectively direct the deployment of defenders. Through experiments, we analyze the perforrmnce of ID-IIG and verify the existence and attainability of the Bayesian Nash equilibrium. 展开更多
关键词 game theory intrusion detection model WMNS
在线阅读 下载PDF
Hybrid Malware Variant Detection Model with Extreme Gradient Boosting and Artificial Neural Network Classifiers 被引量:1
6
作者 Asma A.Alhashmi Abdulbasit A.Darem +5 位作者 Sultan M.Alanazi Abdullah M.Alashjaee Bader Aldughayfiq Fuad A.Ghaleb Shouki A.Ebad Majed A.Alanazi 《Computers, Materials & Continua》 SCIE EI 2023年第9期3483-3498,共16页
In an era marked by escalating cybersecurity threats,our study addresses the challenge of malware variant detection,a significant concern for amultitude of sectors including petroleum and mining organizations.This pap... In an era marked by escalating cybersecurity threats,our study addresses the challenge of malware variant detection,a significant concern for amultitude of sectors including petroleum and mining organizations.This paper presents an innovative Application Programmable Interface(API)-based hybrid model designed to enhance the detection performance of malware variants.This model integrates eXtreme Gradient Boosting(XGBoost)and an Artificial Neural Network(ANN)classifier,offering a potent response to the sophisticated evasion and obfuscation techniques frequently deployed by malware authors.The model’s design capitalizes on the benefits of both static and dynamic analysis to extract API-based features,providing a holistic and comprehensive view of malware behavior.From these features,we construct two XGBoost predictors,each of which contributes a valuable perspective on the malicious activities under scrutiny.The outputs of these predictors,interpreted as malicious scores,are then fed into an ANN-based classifier,which processes this data to derive a final decision.The strength of the proposed model lies in its capacity to leverage behavioral and signature-based features,and most importantly,in its ability to extract and analyze the hidden relations between these two types of features.The efficacy of our proposed APIbased hybrid model is evident in its performance metrics.It outperformed other models in our tests,achieving an impressive accuracy of 95%and an F-measure of 93%.This significantly improved the detection performance of malware variants,underscoring the value and potential of our approach in the challenging field of cybersecurity. 展开更多
关键词 API-based hybrid malware detection model static and dynamic analysis malware detection
在线阅读 下载PDF
Intrusion Detection Model Using Chaotic MAP for Network Coding Enabled Mobile Small Cells 被引量:1
7
作者 Chanumolu Kiran Kumar Nandhakumar Ramachandran 《Computers, Materials & Continua》 SCIE EI 2024年第3期3151-3176,共26页
Wireless Network security management is difficult because of the ever-increasing number of wireless network malfunctions,vulnerabilities,and assaults.Complex security systems,such as Intrusion Detection Systems(IDS),a... Wireless Network security management is difficult because of the ever-increasing number of wireless network malfunctions,vulnerabilities,and assaults.Complex security systems,such as Intrusion Detection Systems(IDS),are essential due to the limitations of simpler security measures,such as cryptography and firewalls.Due to their compact nature and low energy reserves,wireless networks present a significant challenge for security procedures.The features of small cells can cause threats to the network.Network Coding(NC)enabled small cells are vulnerable to various types of attacks.Avoiding attacks and performing secure“peer”to“peer”data transmission is a challenging task in small cells.Due to the low power and memory requirements of the proposed model,it is well suited to use with constrained small cells.An attacker cannot change the contents of data and generate a new Hashed Homomorphic Message Authentication Code(HHMAC)hash between transmissions since the HMAC function is generated using the shared secret.In this research,a chaotic sequence mapping based low overhead 1D Improved Logistic Map is used to secure“peer”to“peer”data transmission model using lightweight H-MAC(1D-LM-P2P-LHHMAC)is proposed with accurate intrusion detection.The proposed model is evaluated with the traditional models by considering various evaluation metrics like Vector Set Generation Accuracy Levels,Key Pair Generation Time Levels,Chaotic Map Accuracy Levels,Intrusion Detection Accuracy Levels,and the results represent that the proposed model performance in chaotic map accuracy level is 98%and intrusion detection is 98.2%.The proposed model is compared with the traditional models and the results represent that the proposed model secure data transmission levels are high. 展开更多
关键词 Network coding small cells data transmission intrusion detection model hashed message authentication code chaotic sequence mapping secure transmission
在线阅读 下载PDF
An efficient approach for shadow detection based on Gaussian mixture model 被引量:2
8
作者 韩延祥 张志胜 +1 位作者 陈芳 陈恺 《Journal of Central South University》 SCIE EI CAS 2014年第4期1385-1395,共11页
An efficient approach was proposed for discriminating shadows from moving objects. In the background subtraction stage, moving objects were extracted. Then, the initial classification for moving shadow pixels and fore... An efficient approach was proposed for discriminating shadows from moving objects. In the background subtraction stage, moving objects were extracted. Then, the initial classification for moving shadow pixels and foreground object pixels was performed by using color invariant features. In the shadow model learning stage, instead of a single Gaussian distribution, it was assumed that the density function computed on the values of chromaticity difference or bright difference, can be modeled as a mixture of Gaussian consisting of two density functions. Meanwhile, the Gaussian parameter estimation was performed by using EM algorithm. The estimates were used to obtain shadow mask according to two constraints. Finally, experiments were carried out. The visual experiment results confirm the effectiveness of proposed method. Quantitative results in terms of the shadow detection rate and the shadow discrimination rate(the maximum values are 85.79% and 97.56%, respectively) show that the proposed approach achieves a satisfying result with post-processing step. 展开更多
关键词 shadow detection Gaussian mixture model EM algorithm
在线阅读 下载PDF
Real-time lane departure warning system based on principal component analysis of grayscale distribution and risk evaluation model 被引量:4
9
作者 张伟伟 宋晓琳 张桂香 《Journal of Central South University》 SCIE EI CAS 2014年第4期1633-1642,共10页
A technology for unintended lane departure warning was proposed. As crucial information, lane boundaries were detected based on principal component analysis of grayscale distribution in search bars of given number and... A technology for unintended lane departure warning was proposed. As crucial information, lane boundaries were detected based on principal component analysis of grayscale distribution in search bars of given number and then each search bar was tracked using Kalman filter between frames. The lane detection performance was evaluated and demonstrated in ways of receiver operating characteristic, dice similarity coefficient and real-time performance. For lane departure detection, a lane departure risk evaluation model based on lasting time and frequency was effectively executed on the ARM-based platform. Experimental results indicate that the algorithm generates satisfactory lane detection results under different traffic and lighting conditions, and the proposed warning mechanism sends effective warning signals, avoiding most false warning. 展开更多
关键词 lane departure warning system lane detection lane tracking principal component analysis risk evaluation model ARM-based real-time system
在线阅读 下载PDF
Multiple Detection Model Fusion Framework for Printed Circuit Board Defect Detection
10
作者 武星 张庆丰 +2 位作者 王健嘉 姚骏峰 郭毅可 《Journal of Shanghai Jiaotong university(Science)》 EI 2023年第6期717-727,共11页
The printed circuit board(PCB)is an indispensable component of electronic products,which deter-mines the quality of these products.With the development and advancement of manufacturing technology,the layout and struct... The printed circuit board(PCB)is an indispensable component of electronic products,which deter-mines the quality of these products.With the development and advancement of manufacturing technology,the layout and structure of PCB are getting complicated.However,there are few effective and accurate PCB defect detection methods.There are high requirements for the accuracy of PCB defect detection in the actual pro-duction environment,so we propose two PCB defect detection frameworks with multiple model fusion including the defect detection by multi-model voting method(DDMV)and the defect detection by multi-model learning method(DDML).With the purpose of reducing wrong and missing detection,the DDMV and DDML integrate multiple defect detection networks with different fusion strategies.The effectiveness and accuracy of the proposed framework are verified with extensive experiments on two open-source PCB datasets.The experimental results demonstrate that the proposed DDMV and DDML are better than any other individual state-of-the-art PCB defect detection model in F1-score,and the area under curve value of DDML is also higher than that of any other individual detection model.Furthermore,compared with DDMV,the DDML with an automatic machine learning method achieves the best performance in PCB defect detection,and the Fl-score on the two datasets can reach 99.7%and 95.6%respectively. 展开更多
关键词 printed circuit board(PCB) defect detection model fusion object detection model
原文传递
A New Probability of Detection Model for Updating Crack Distribution of Offshore Structures
11
作者 李典庆 张圣坤 唐文勇 《海洋工程:英文版》 2003年第3期327-340,共14页
There exists model uncertainty of probability of detection for inspecting ship structures with nondestructive inspection techniques. Based on a comparison of several existing probability of detection (POD) models, a n... There exists model uncertainty of probability of detection for inspecting ship structures with nondestructive inspection techniques. Based on a comparison of several existing probability of detection (POD) models, a new probability of detection model is proposed for the updating of crack size distribution. Furthermore, the theoretical derivation shows that most existing probability of detection models are special cases of the new probability of detection model. The least square method is adopted for determining the values of parameters in the new POD model. This new model is also compared with other existing probability of detection models. The results indicate that the new probability of detection model can fit the inspection data better. This new probability of detection model is then applied to the analysis of the problem of crack size updating for offshore structures. The Bayesian updating method is used to analyze the effect of probability of detection models on the posterior distribution of a crack size. The results show that different probabilities of detection models generate different posterior distributions of a crack size for offshore structures. 展开更多
关键词 nondestructive inspection probability of detection model Bayesian updating offshore structures
在线阅读 下载PDF
Application of NYBC blood detection model
12
《中国输血杂志》 CAS CSCD 2001年第S1期354-,共1页
关键词 Application of NYBC blood detection model
暂未订购
中国丹顶鹤迁徙路线湿地景观格局演化模式及其驱动因素
13
作者 尹梓烨 那晓东 《生态学报》 北大核心 2026年第4期1800-1814,共15页
探究丹顶鹤迁徙路线上的湿地景观格局演化模式及驱动因素,有利于构建促进物种迁徙的生态廊道、科学制定湿地修复策略、维护湿地生态系统稳定。以丹顶鹤迁徙路线上的湿地为对象,获取1990—2020年共七期土地利用/覆被数据,基于改进过后的... 探究丹顶鹤迁徙路线上的湿地景观格局演化模式及驱动因素,有利于构建促进物种迁徙的生态廊道、科学制定湿地修复策略、维护湿地生态系统稳定。以丹顶鹤迁徙路线上的湿地为对象,获取1990—2020年共七期土地利用/覆被数据,基于改进过后的景观格局状态与演化识别模型(SEDM)研究湿地格局演化模式的时空分布特征,并利用地理探测器分析其驱动因素。结果表明:(1)1990—2015年间湿地面积减少了7994km^(2),湿地萎缩严重,大量湿地转化为耕地、人工表面。2015—2020年湿地面积增加,而转入湿地的主要类型为耕地、水域和林地。(2)湿地景观格局的演化具有明显的阶段性特征,1990—2000年间湿地格局演化以破碎类型为主,收缩与减少模式占主导;2000—2015年湿地面积减少趋势放缓,发生演化的格网数量显著减少,湿地格局演化模式由减少模式向新增模式过渡;2015—2020年湿地景观格局演化以扩张类型为主,增加与新增演化模式为主导,湿地得到有效恢复。(3)湿地格局演化频数较高的区域集中在东北松嫩平原、三江平原、黄河三角洲与盐城滨海地区,气温、降水和耕地对湿地格局演化影响最为显著。其中在东北地区的松嫩和三江平原湿地格局演化频繁主要受气候变化、耕地扩张影响,而黄河三角洲和盐城湿地格局演化主要受人类活动的影响。总体来看,气候变化虽然是湿地格局演化的关键因素,但湿地格局演化从破碎转向扩张模式,主要是受人为因素的驱动。 展开更多
关键词 湿地 the state-and-evolution detection models(SEDM)模型 景观格局演化模式 地理探测器 丹顶鹤
在线阅读 下载PDF
Anomaly-based model for detecting HTTP-tunnel traffic using network behavior analysis 被引量:3
14
作者 李世淙 Yun Xiaochun Zhang Yongzheng 《High Technology Letters》 EI CAS 2014年第1期63-69,共7页
Increasing time-spent online has amplified users' exposure to tile tilreat oI miormanon leakage. Although existing security systems (such as firewalls and intrusion detection systems) can satisfy most of the securi... Increasing time-spent online has amplified users' exposure to tile tilreat oI miormanon leakage. Although existing security systems (such as firewalls and intrusion detection systems) can satisfy most of the security requirements of network administrators, they are not suitable for detecting the activities of applying the HTTP-tunnel technique to steal users' private information. This paper focuses on a network behavior-based method to address the limitations of the existing protection systems. At first, it analyzes the normal network behavior pattern over HTI'P traffic and select four features. Then, it pres- ents an anomaly-based detection model that applies a hierarchical clustering technique and a scoring mechanism. It also uses real-world data to validate that the selected features are useful. The experiments have demonstrated that the model could achieve over 93% hit-rate with only about 3% false- positive rate. It is regarded confidently that the approach is a complementary technique to the existing security systems. 展开更多
关键词 network security anomaly detection model hierarchical clustering HTFP-tunnel
在线阅读 下载PDF
Method to Detect Granary Storage Weight Based on the Janssen Model 被引量:3
15
作者 ZHANG Dexian ZHANG Miao +2 位作者 ZHANG Qinghui ZHANG Yuan LYU Lei 《Grain & Oil Science and Technology》 2018年第1期20-27,共8页
This study proposes a new model of granary storage weight detection based on the Janssen model to satisfy the strategic requirements of granary storage quantity detection in China. The model theoretically elucidates t... This study proposes a new model of granary storage weight detection based on the Janssen model to satisfy the strategic requirements of granary storage quantity detection in China. The model theoretically elucidates the relationship between granary storage weight and bottom/side pressure. A new layout of pressure sensors along the inner and outer rings is also proposed to obtain the pressure value. The experimental results indicate that the detection error of the proposed model is significantly lower than 1% with respect to the low-cost detection system, and this effectively satisfies the actual requirement for real-time monitoring of granary storage quantity. 展开更多
关键词 Granary storage quantity detection Janssen model Pressure sensor detection model detection accuracy
在线阅读 下载PDF
An aligned mixture probabilistic principal component analysis for fault detection of multimode chemical processes 被引量:5
16
作者 杨雅伟 马玉鑫 +1 位作者 宋冰 侍洪波 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第8期1357-1363,共7页
A novel approach named aligned mixture probabilistic principal component analysis(AMPPCA) is proposed in this study for fault detection of multimode chemical processes. In order to exploit within-mode correlations,the... A novel approach named aligned mixture probabilistic principal component analysis(AMPPCA) is proposed in this study for fault detection of multimode chemical processes. In order to exploit within-mode correlations,the AMPPCA algorithm first estimates a statistical description for each operating mode by applying mixture probabilistic principal component analysis(MPPCA). As a comparison, the combined MPPCA is employed where monitoring results are softly integrated according to posterior probabilities of the test sample in each local model. For exploiting the cross-mode correlations, which may be useful but are inadvertently neglected due to separately held monitoring approaches, a global monitoring model is constructed by aligning all local models together. In this way, both within-mode and cross-mode correlations are preserved in this integrated space. Finally, the utility and feasibility of AMPPCA are demonstrated through a non-isothermal continuous stirred tank reactor and the TE benchmark process. 展开更多
关键词 Multimode process monitoring Mixture probabilistic principal component analysis model alignment Fault detection
在线阅读 下载PDF
Adaptive learning rate GMM for moving object detection in outdoor surveillance for sudden illumination changes 被引量:1
17
作者 HOCINE Labidi 曹伟 +2 位作者 丁庸 张笈 罗森林 《Journal of Beijing Institute of Technology》 EI CAS 2016年第1期145-151,共7页
A dynamic learning rate Gaussian mixture model(GMM)algorithm is proposed to deal with the problem of slow adaption of GMM in the case of moving object detection in the outdoor surveillance,especially in the presence... A dynamic learning rate Gaussian mixture model(GMM)algorithm is proposed to deal with the problem of slow adaption of GMM in the case of moving object detection in the outdoor surveillance,especially in the presence of sudden illumination changes.The GMM is mostly used for detecting objects in complex scenes for intelligent monitoring systems.To solve this problem,a mixture Gaussian model has been built for each pixel in the video frame,and according to the scene change from the frame difference,the learning rate of GMM can be dynamically adjusted.The experiments show that the proposed method gives good results with an adaptive GMM learning rate when we compare it with GMM method with a fixed learning rate.The method was tested on a certain dataset,and tests in the case of sudden natural light changes show that our method has a better accuracy and lower false alarm rate. 展开更多
关键词 object detection background modeling Gaussian mixture model(GMM) learning rate frame difference
在线阅读 下载PDF
Modeling and Global Conflict Analysis of Firewall Policy 被引量:3
18
作者 LIANG Xiaoyan XIA Chunhe +2 位作者 JIAO Jian HU Junshun LI Xiaojian 《China Communications》 SCIE CSCD 2014年第5期124-135,共12页
The global view of firewall policy conflict is important for administrators to optimize the policy.It has been lack of appropriate firewall policy global conflict analysis,existing methods focus on local conflict dete... The global view of firewall policy conflict is important for administrators to optimize the policy.It has been lack of appropriate firewall policy global conflict analysis,existing methods focus on local conflict detection.We research the global conflict detection algorithm in this paper.We presented a semantic model that captures more complete classifications of the policy using knowledge concept in rough set.Based on this model,we presented the global conflict formal model,and represent it with OBDD(Ordered Binary Decision Diagram).Then we developed GFPCDA(Global Firewall Policy Conflict Detection Algorithm) algorithm to detect global conflict.In experiment,we evaluated the usability of our semantic model by eliminating the false positives and false negatives caused by incomplete policy semantic model,of a classical algorithm.We compared this algorithm with GFPCDA algorithm.The results show that GFPCDA detects conflicts more precisely and independently,and has better performance. 展开更多
关键词 firewall policy semantic model conflict analysis conflict detection
在线阅读 下载PDF
A generalized model of TiOx-based memristive devices and its application for image processing 被引量:1
19
作者 张江伟 汤振森 +4 位作者 许诺 王耀 孙红辉 王之元 方粮 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第9期70-81,共12页
Memristive technology has been widely explored, due to its distinctive properties, such as nonvolatility, high density,versatility, and CMOS compatibility. For memristive devices, a general compact model is highly fav... Memristive technology has been widely explored, due to its distinctive properties, such as nonvolatility, high density,versatility, and CMOS compatibility. For memristive devices, a general compact model is highly favorable for the realization of its circuits and applications. In this paper, we propose a novel memristive model of TiOx-based devices, which considers the negative differential resistance(NDR) behavior. This model is physics-oriented and passes Linn's criteria. It not only exhibits sufficient accuracy(IV characteristics within 1.5% RMS), lower latency(below half the VTEAM model),and preferable generality compared to previous models, but also yields more precise predictions of long-term potentiation/depression(LTP/LTD). Finally, novel methods based on memristive models are proposed for gray sketching and edge detection applications. These methods avoid complex nonlinear functions required by their original counterparts. When the proposed model is utilized in these methods, they achieve increased contrast ratio and accuracy(for gray sketching and edge detection, respectively) compared to the Simmons model. Our results suggest a memristor-based network is a promising candidate to tackle the existing inefficiencies in traditional image processing methods. 展开更多
关键词 memristor modeling memristor-based network gray sketching edge detection
原文传递
Rapid Detection of Cement Raw Meal Composition Based on Near Infrared Spectroscopy
20
作者 HUANG Bing WANG Xiaohong +1 位作者 JIANG Ping QIAO Jia 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2022年第5期900-904,共5页
The composition of cement raw materials was detected by near-infrared spectroscopy.It was found that the BiPLS-SiPLS method selected the NIR spectral band of cement raw materials,and the partial least squares regressi... The composition of cement raw materials was detected by near-infrared spectroscopy.It was found that the BiPLS-SiPLS method selected the NIR spectral band of cement raw materials,and the partial least squares regression algorithm was adopted to establish a quantitative correction model of cement raw materials with good prediction effect.The root-mean-square errors of SiO_(2),Al_(2)O_(3),Fe_(2)O_(3) and CaO calibration were 0.142,0.072,0.034 and 0.188 correspondingly.The results show that the NIR spectroscopy method can detect the composition of cement raw meal rapidly and accurately,which provides a new perspective for the composition detection of cement raw meal. 展开更多
关键词 near infrared spectroscopy cement raw meal band selection detection model
原文传递
上一页 1 2 3 下一页 到第
使用帮助 返回顶部