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A Novel SAR Image Ship Small Targets Detection Method 认领
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作者 Yu Song Min Li +3 位作者 Xiaohua Qiu Weidong Du Yujie He Xiaoxiang Qi 《电脑和通信(英文)》 2021年第2期57-71,共15页
To satisfy practical requirements of high real-time accuracy and low computational complexity of synthetic aperture radar (SAR) image ship small target detection, this paper proposes a small ship target detection meth... To satisfy practical requirements of high real-time accuracy and low computational complexity of synthetic aperture radar (SAR) image ship small target detection, this paper proposes a small ship target detection method based on the improved You Only Look Once Version 3 (YOLOv3). The main contributions of this study are threefold. First, the feature extraction network of the original YOLOV3 algorithm is replaced with the VGG16 network convolution layer. Second, general convolution is transformed into depthwise separable convolution, thereby reducing the computational cost of the algorithm. Third, a residual network structure is introduced into the feature extraction network to reuse the shallow target feature information, which enhances the detailed features of the target and ensures the improvement in accuracy of small target detection performance. To evaluate the performance of the proposed method, many experiments are conducted on public SAR image datasets. For ship targets with complex backgrounds and small ship targets in the SAR image, the effectiveness of the proposed algorithm is verified. Results show that the accuracy and recall rate improved by 5.31% and 2.77%, respectively, compared with the original YOLOV3. Furthermore, the proposed model not only significantly reduces the computational effort, but also improves the detection accuracy of ship small target. 展开更多
关键词 The SAR Images The Neural Network Ship Small Target Target Detection
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Research on Adaptive Threshold of Received Signal in Communication System 认领
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作者 Xizheng Ke Xukuan Ji 《光学与光子学期刊(英文)》 2021年第1期1-11,共11页
When the light beam propagates in the atmosphere, the signal will be absorbed and scattered by the gas molecules and water mist in the atmosphere, which will cause the loss of power rate. The complex atmospheric envir... When the light beam propagates in the atmosphere, the signal will be absorbed and scattered by the gas molecules and water mist in the atmosphere, which will cause the loss of power rate. The complex atmospheric environment will produce a variety of adverse effects on the signal. The interference produced by these effects overlaps with each other, which will seriously affect the strength of the received signal. Therefore, how to effectively suppress the atmospheric turbulence effect in the random atmospheric turbulence channel, ensure the normal transmission of the signal in the atmospheric channel, and reduce the bit error rate of the communication system, is very necessary to improve the communication system. When processing the received signal, it is an important step to detect the transmitted signal by comparing the received signal with the threshold. In this paper, based on the atmospheric turbulence distribution model, the adaptive signal decision threshold is obtained through the estimation of high-order cumulant. Monte Carlo method is used to verify the performance of adaptive threshold detection. The simulation results show that the high-order cumulant estimation of atmospheric turbulence parameters can realize the adaptive change of the decision threshold with the channel condition. It is shown that the adaptive threshold detection can effectively restrain atmospheric turbulence, improve the performance of free space optical and improve the communication quality. 展开更多
关键词 Free Space Optical Adaptive Threshold Detection Higller-Order Cumulants
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Development and Evaluation of an Optical Sensing System for Detection of Herbicide Spray Droplets 认领
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作者 Yanbo Huang Wei Ma Daniel Fisher 《物联网(英文)》 2021年第1期1-9,共9页
Real time monitoring of herbicide spray droplet drift is important for crop production management and environmental protection. Existing spray droplet drift detection methods, such as water-sensitive paper and tracers... Real time monitoring of herbicide spray droplet drift is important for crop production management and environmental protection. Existing spray droplet drift detection methods, such as water-sensitive paper and tracers of fluorescence and Rubidium chloride, are time-consuming and laborious, and the accuracies are not high in general. Also, the tracer methods indirectly quantify the spray deposition from the concentration of the tracer and may change the drift characteristics of the sprayed herbicides. In this study, a new optical sensor system was developed to directly detect the spray droplets without the need to add any tracer in the spray liquid. The system was prototyped using a single broadband programmable LED light source and a near infrared sensor containing 6 broadband spectral detectors at 610, 680, 730, 760, 810, and 860 nm to build a detection system for monitoring and analysis of herbicide spray droplet drift. A rotatory structure driven by a stepper motor in the system was created to shift the droplet capture line going under the optical sensor to measure and collect the spectral signals that reflect spray drift droplets along the line. The system prototype was tested for detection of small (Very Fine and Fine), medium (Medium), and large (Coarse) droplets within the droplet classifications of the American Society of Agricultural and Biological Engineers. Laboratory testing results indicated that the system could detect the droplets of different sizes and determine the droplet positions on the droplet capture line with 100% accuracy at the wavelength of 610 nm selected from the 6 bands to detect the droplets. 展开更多
关键词 Near Infrared (NIR) Sensor Spray Drift Droplet Detection Plant Protection
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A Hybrid Intrusion Detection System for Smart Home Security Based on Machine Learning and User Behavior 认领
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作者 Faisal Alghayadh Debatosh Debnath 《物联网(英文)》 2021年第1期10-25,共16页
With technology constantly becoming present in people’s lives, smart homes are increasing in popularity. A smart home system controls lighting, temperature, security camera systems, and appliances. These devices and ... With technology constantly becoming present in people’s lives, smart homes are increasing in popularity. A smart home system controls lighting, temperature, security camera systems, and appliances. These devices and sensors are connected to the internet, and these devices can easily become the target of attacks. To mitigate the risk of using smart home devices, the security and privacy thereof must be artificially smart so they can adapt based on user behavior and environments. The security and privacy systems must accurately analyze all actions and predict future actions to protect the smart home system. We propose a Hybrid Intrusion Detection (HID) system using machine learning algorithms, including random forest, X gboost, decision tree, K -nearest neighbors, and misuse detection technique. 展开更多
关键词 Anomaly Detection Smart Home Systems Behavioral Patterns SECURITY Threats
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Review of Anomaly Detection Systems in Industrial Control Systems Using Deep Feature Learning Approach 认领
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作者 Raogo Kabore Adlès Kouassi +3 位作者 Rodrigue N’goran Olivier Asseu Yvon Kermarrec Philippe Lenca 《工程(英文)(1947-3931)》 2021年第1期30-44,共15页
Industrial Control Systems (ICS) or SCADA networks are increasingly targeted by cyber-attacks as their architectures shifted from proprietary hardware, software and protocols to standard and open sources ones. Further... Industrial Control Systems (ICS) or SCADA networks are increasingly targeted by cyber-attacks as their architectures shifted from proprietary hardware, software and protocols to standard and open sources ones. Furthermore, these systems which used to be isolated are now interconnected to corporate networks and to the Internet. Among the countermeasures to mitigate the threats, anomaly detection systems play an important role as they can help detect even unknown attacks. Deep learning which has gained a great attention in the last few years due to excellent results in image, video and natural language processing is being used for anomaly detection in information security, particularly in SCADA networks. The salient features of the data from SCADA networks are learnt as hierarchical representation using deep architectures, and those learnt features are used to classify the data into normal or anomalous ones. This article is a review of various architectures such as Convolutional Neural Network (CNN), Recurrent Neural Network (RNN), Stacked Autoencoder (SAE), Long Short Term Memory (LSTM), or a combination of those architectures, for anomaly detection purpose in SCADA networks. 展开更多
关键词 ICS SCADA Unsupervised Feature Learning Deep Learning Anomaly Detection
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Magnetic Applications to Subsurface and Groundwater Investigations: A Case Study from Wadi El Assiuti, Egypt 认领
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作者 Ahmed Mohamed Elsayed M. Abu El Ella 《地球科学国际期刊(英文)》 2021年第2期77-101,共25页
Wadi El Assiuti represents a promising area for agricultural development and building new communities far from the overpopulated areas in the Nile Val-ley. An integrated approach of satellite-based data and geophysica... Wadi El Assiuti represents a promising area for agricultural development and building new communities far from the overpopulated areas in the Nile Val-ley. An integrated approach of satellite-based data and geophysical data with borehole data was used for defining the area of interest, the sediment thick-ness, delineating the subsurface structures, and mapping the depth to the basement rocks, and defining the groundwater aquifers. Findings are: 1) Dramatic changes are detected in the anthropogenic activities at the entrance area of the wadi, making stress and heavy exploitation of the groundwater resources. However, the central and northeastern regions show no development;2) Several structural trends in the directions of NNW, NW, NE, and E-W are cutting the basement rocks and sedimentary cover;3) The depth to the basement rocks is increasing eastward from ~2.24 km to ~4.84 km;4) Three groundwater-bearing reservoirs are represented by the shallow Qua-ternary, the fractured limestone, and the deep Nubian sandstone aquifers;5) The deep-seated faults are affecting the area and rising groundwater from the deeper Nubian aquifer along its sub-vertical trend;and 6) The results are in-formative and used to define the suitable sites for water well drilling. 展开更多
关键词 Wadi El Assiuti Aeromagnetic Data Change Detection Structural Trends Sediment Thickness Groundwater Aquifers
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Prognosis and Survival of Nasopharyngeal Cancer in Cameroon 认领
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作者 Jean Paul Engbang Amadou Njifou +4 位作者 Therè se Daphné e Tjomb Maurice Mpessa Louis Richard Njock 《耳鼻喉(英文)》 2021年第1期6-19,共14页
<strong>Background:</strong> Nasopharyngeal carcinoma (NPC) is an entity belonging to up-per aerodigestive tract Cancers. NPC is more widespread in Southern China and South East Asia. In our country, it is... <strong>Background:</strong> Nasopharyngeal carcinoma (NPC) is an entity belonging to up-per aerodigestive tract Cancers. NPC is more widespread in Southern China and South East Asia. In our country, it is the leading cause of head and neck cancers. Its prognosis remains bleak because of the late stage at diagnostic. <strong>Objectives:</strong> The objectives of this study were to determine the prognostic fac-tors and survival rate of patients with nasopharyngeal cancer in six reference hospitals in Cameroon. <strong>Material and Methods:</strong> It was a retrospective analytic study, conducted from January 2009 to December 2018. It was conducted in oncology, surgery and Ear Nose and Throat (ENT) units of six reference hos-pitals. Data from 114 files meeting the inclusion were collected. We have drawn survival curves and determined the different survival probabilities with the help of Kaplan-Meier Method. The different survival curves were compared using the Log-Rank Test (P < 0.05), variables that were statistically associated with the 5% cut off were introduced into the Cox regression model for multivariate analysis, thus allowing us to bring out the prognostic factors significantly associated with survival. <strong>Results:</strong> The mean age at the time of diagnosis of the 114 patients recruited was 45.30 ± 17.14 years. The predominant histological type was the UCNT (Undifferentiated Carcinoma of the NasoPharynx) representing 84.2%. According to the WHO classification, 2 patients were classified as stage I (1.8%), 33 as stage II (28.9%), 42 as stage III (36.8%), 25 as stage IV A (21.9%) and 12 as stage IV B (10.5%). At the end of the survival assessment period, 34 patients were dead and 73 patients (64%) were still alive. The median overall survival was 44 months. The overall survival rates at one, two, three, and four years were 80%;74%;68%;44%, respectively. The prognostic factors associated with poor survival were: late consultation time of more than 12 months, N3 lymph node involvement, 3 and 4 adva 展开更多
关键词 Nasopharyngeal Cancer SURVIVAL Prognostic Factors DETECTION Cameroon
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基于核酸适配体调控噻菁染料聚集体构建铅离子检测方法 认领
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作者 赵晗 于丽佳 +3 位作者 吴志生 张颖琳 张华伟 师晓栋 《食品与机械》 北大核心 2021年第1期73-78,共6页
基于调控噻菁染料(Dye2)的超分子自组装性质及其与核酸适配体(T30695)特异性结合的能力,构建了Pb2+的特异性识别模块。结果表明,当体系中加入Pb2+时,T30695单链形成G-四链体,并将二聚体形式存在的噻菁染料诱导解聚为单体,引起422,445nm... 基于调控噻菁染料(Dye2)的超分子自组装性质及其与核酸适配体(T30695)特异性结合的能力,构建了Pb2+的特异性识别模块。结果表明,当体系中加入Pb2+时,T30695单链形成G-四链体,并将二聚体形式存在的噻菁染料诱导解聚为单体,引起422,445nm处紫外吸收峰变化,仅需通过UV-vis光谱仪便可实现对Pb2+的高选择性、高灵敏度识别。该体系在Pb2+浓度为0.25~10.00μmol/L时具有线性关系(R2=0.992 7),其检出限为0.115μmol/L。 展开更多
关键词 核酸适配体 噻菁染料 铅离子(Ⅱ) G-四链体 检测
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掺粉煤灰水利水电建筑混凝土强度检测方法研究 认领
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作者 刘瑞春 《粉煤灰综合利用》 CAS 2021年第1期108-112,共5页
传统混凝土强度检测方法对声波信号频率的计算存在误差,导致检测结果不准确,为此提出掺粉煤灰水利水电建筑混凝土强度检测方法。采用敲击的方式,使混凝土内部产生声波信号,用传感器记录冲击回波频率,计算冲击回波频率传播速度,并在振幅... 传统混凝土强度检测方法对声波信号频率的计算存在误差,导致检测结果不准确,为此提出掺粉煤灰水利水电建筑混凝土强度检测方法。采用敲击的方式,使混凝土内部产生声波信号,用传感器记录冲击回波频率,计算冲击回波频率传播速度,并在振幅谱频谱中分析出声波频率峰值。测定冲击持续时间,计算冲击回波反射面深度以确定混凝土碳化程度,得出掺粉煤灰水利水电建筑混凝土强度值。试验结果显示:该方法得到的声波信号频率、混凝土强度值与实测最为接近,检测精度高。 展开更多
关键词 掺粉煤灰 水利水电建筑 混凝土强度 检测 声波信号 频率
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基于Grubbs准则和区间搜索的双频GPS周跳探测 认领
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作者 黄德武 王建英 《大地测量与地球动力学》 北大核心 2021年第3期268-273,共6页
GPS周跳是影响监测成果精度的重要因素之一,其多值性及如何判断各自频率上的周跳尤为重要。本文针对双频周跳探测,以ΔΦ=ΔN 1-(λ2/λ1)ΔN 2为主方程,提出一种通过Grubbs准则探测ΔN 1、ΔN 2异常值的方法来约束双频周跳ΔN 1、ΔN ... GPS周跳是影响监测成果精度的重要因素之一,其多值性及如何判断各自频率上的周跳尤为重要。本文针对双频周跳探测,以ΔΦ=ΔN 1-(λ2/λ1)ΔN 2为主方程,提出一种通过Grubbs准则探测ΔN 1、ΔN 2异常值的方法来约束双频周跳ΔN 1、ΔN 2的搜索范围,通过计算满足主方程整数解的方式探测周跳。通过采样率为1 s、5 s和15 s的GPS数据进行验证,结果表明,采用本文方法不仅可以解决普通周跳和特殊周跳的多值问题,而且能准确探测各频率上的周跳,计算准确率达100%。 展开更多
关键词 监测 周跳 多值 探测
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Semiautomated Class Attendance Monitoring Using Smartphone Technology 认领
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作者 Louise Cronjé Ian Sanders 《人工智能技术学报(英文)》 2021年第1期9-20,共12页
Class attendance is important.Class attendance recording is often done using“roll-call”or signing attendance registers.These are time consuming,easy to cheat,and it is difficult to draw any information from them.The... Class attendance is important.Class attendance recording is often done using“roll-call”or signing attendance registers.These are time consuming,easy to cheat,and it is difficult to draw any information from them.There are other,expensive alternatives to automate attendance recording with varying accuracy.This study experimented with a smartphone camera and different combinations of face detection and recognition algorithms to determine if it can be used to record attendance successfully,while keeping the solution cost-effective.The effect of different class sizes was also investigated.The research was done within a pragmatism philosophy,using a prototype in a field experiment.The algorithms that were used are Viola–Jones(Haar features),deep neural network and histogram of oriented gradients for detection,and eigenfaces,fisherfaces,and local binary pattern histogram for recognition.The best combination was Viola–Jones combined with fisherfaces,with a mean accuracy of 54%for a class of 10 students and 34.5%for a class of 22 students.The best all over performance on a single class photo was 70%(class size 10).As is,this prototype is not accurate enough to use,but with a few adjustments,it may become a cheap,easy-to-implement solution to the attendance recording problem. 展开更多
关键词 class attendance face detection face recognition SMARTPHONE
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Defect detection in freight railcar tapered-roller bearings using vibration techniques 认领
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作者 Constantine Tarawneh Joseph Montalvo Brent Wilson 《铁道工程科学:英文版》 2021年第1期42-58,共17页
Currently,there are two types of defect detection systems used to monitor the health of freight railcar bearings in service:wayside hot-box detection systems and trackside acoustic detection systems.These systems have... Currently,there are two types of defect detection systems used to monitor the health of freight railcar bearings in service:wayside hot-box detection systems and trackside acoustic detection systems.These systems have proven to be inefficient in accurately determining bearing health,especially in the early stages of defect development.To that end,a prototype onboard bearing condition monitoring system has been developed and validated through extensive laboratory testing and a designated field test in 2015 at the Transportation Technology Center,Inc.in Pueblo,CO.The devised system can accurately and reliably characterize the health of bearings based on developed vibration thresholds and can identify defective taperedroller bearing components with defect areas smaller than 12.9 cm2 while in service. 展开更多
关键词 Railcar health monitoring Onboard condition monitoring systems Bearing defect detection Bearing vibration signatures Bearing spectral analysis
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可视化SRCA技术检测转基因大豆及其制品的研究 认领
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作者 徐俐俐 杨倩 +4 位作者 赵峥山 卢鑫 郭威 苑宁 张伟 《食品科技》 CAS 北大核心 2021年第2期287-293,共7页
为保障转基因大豆的可追溯性以及消费者的知情权和选择权,开发快速、灵敏、准确的转基因大豆检测方法显得尤为重要。文章建立了一种用于检测转基因大豆及其制品的可视化跨越式滚环等温扩增(Saltatory rolling circle amplification,SRCA... 为保障转基因大豆的可追溯性以及消费者的知情权和选择权,开发快速、灵敏、准确的转基因大豆检测方法显得尤为重要。文章建立了一种用于检测转基因大豆及其制品的可视化跨越式滚环等温扩增(Saltatory rolling circle amplification,SRCA)技术。根据抗除草剂草甘膦CP4-EPSPS基因设计引物,进行特异性验证,并对该方法的灵敏度和检出限进行研究。通过检测68份实际样品,对该方法的相对敏感度、相对特异性和相对符合率进行评价。结果表明:可视化SRCA方法具有良好的特异性,其检测转基因大豆的灵敏度为8.8×10^(0)fg/μL,是SRCA凝胶电泳法的10倍,是PCR方法的1000倍。在人工加标样品中,可视化SRCA方法的检出限为0.01%(w/w),均显著低于SRCA凝胶电泳法和PCR方法。与行业检测标准(SN/T 1204—2016)相比,可视化SRCA方法的相对敏感性、相对特异性和相对符合率分别为100.00%、98.41%、98.52%。可视化SRCA方法具有操作简便、灵敏度高、特异性强、检出限低等优点,可以灵敏、高效地检测转基因成分,有利于在检测机构的推广应用。 展开更多
关键词 跨越式滚环等温扩增(SRCA) 转基因大豆 CP4-EPSPS基因 可视化 检测
Individual Identification of Electronic Equipment Based on Electromagnetic Fingerprint Characteristics 认领
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作者 Han Xu Hongxin Zhang +3 位作者 Jun Xu Guangyuan Wang Yun Nie Hua Zhang 《中国通信:英文版》 SCIE 2021年第1期169-180,共12页
With the rapid development of communication and computer,the individual identification technology of communication equipment has been brought to many application scenarios.The identification of the same type of electr... With the rapid development of communication and computer,the individual identification technology of communication equipment has been brought to many application scenarios.The identification of the same type of electronic equipment is of considerable significance,whether it is the identification of friend or foe in military applications,identity determination,radio spectrum management in civil applications,equipment fault diagnosis,and so on.Because of the limited-expression ability of the traditional electromagnetic signal representation methods in the face of complex signals,a new method of individual identification of the same equipment of communication equipment based on deep learning is proposed.The contents of this paper include the following aspects:(1)Considering the shortcomings of deep learning in processing small sample data,this paper provides a universal and robust feature template for signal data.This paper constructs a relatively complete signal template library from multiple perspectives,such as time domain and transform domain features,combined with high-order statistical analysis.Based on the inspiration of the image texture feature,characteristics of amplitude histogram of signal and the signal amplitude co-occurrence matrix(SACM)are proposed in this paper.These signal features can be used as a signal fingerprint template for individual identification.(2)Considering the limitation of the recognition rate of a single classifier,using the integrated classifier has achieved better generalization ability.The final average accuracy of 5 NRF24LE1 modules is up to 98%and solved the problem of individual identification of the same equipment of communication equipment under the condition of the small sample,low signal-to-noise ratio. 展开更多
关键词 signal fingerprints histogram-based signal feature starting point detection signal level cooccurrence matrix ensemble Learningn
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全氟化合物的环境污染及检测方法 认领
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作者 吴晓妍 廖佳 《化学世界》 CAS 2021年第1期8-13,共6页
全氟化合物是环境中一种新型的持久性有机污染物。近年来,随着全氟化合物的广泛使用,其环境污染问题日益受到人们关注。因此,有必要对其环境行为和检测方法进行研究。综述了全氟化合物在水体、沉积物、大气中的污染现状,总结了关于全氟... 全氟化合物是环境中一种新型的持久性有机污染物。近年来,随着全氟化合物的广泛使用,其环境污染问题日益受到人们关注。因此,有必要对其环境行为和检测方法进行研究。综述了全氟化合物在水体、沉积物、大气中的污染现状,总结了关于全氟化合物的采集技术、前处理技术以及检测方法的研究进展。 展开更多
关键词 全氟化合物 污染现状 分析检测
严重急性呼吸综合征冠状病毒2检测方法的研究进展 认领
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作者 韩一芳(综述) 张锦海 +1 位作者 汪春晖 朱进(审校) 《医学研究生学报》 CAS 北大核心 2021年第2期205-210,共6页
2019年底,严重急性呼吸综合征冠状病毒2感染疫情引起全球关注,已影响180多个国家和地区,2020年3月11日,世界卫生组织(WHO)宣布将新型冠状病毒肺炎列为全球性大流行病。早诊断、早隔离、早治疗可降低病毒传播的风险,因此快速准确的实验... 2019年底,严重急性呼吸综合征冠状病毒2感染疫情引起全球关注,已影响180多个国家和地区,2020年3月11日,世界卫生组织(WHO)宣布将新型冠状病毒肺炎列为全球性大流行病。早诊断、早隔离、早治疗可降低病毒传播的风险,因此快速准确的实验室诊断尤为重要。文章就严重急性呼吸综合征冠状病毒2的核酸检测和免疫学检测方法进行综述。 展开更多
关键词 严重急性呼吸综合征冠状病毒2 新型冠状病毒感染的肺炎 检测
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A data analytics-based tool for the detection and diagnosis of anomalous daily energy patterns in buildings 认领
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作者 Marco Savino Piscitelli Silvio Brandi +1 位作者 Alfonso Capozzoli Fu Xiao 《建筑模拟(英文)》 SCIE EI 2021年第1期131-147,共17页
In this paper,a tool for the detection and diagnosis of anomalous electrical daily energy patterns relative to a transformer substation of a university campus was developed and tested.Through an innovative pattern rec... In this paper,a tool for the detection and diagnosis of anomalous electrical daily energy patterns relative to a transformer substation of a university campus was developed and tested.Through an innovative pattern recognition analysis consisting in a multi-step clustering process,six clusters of anomalous daily load profiles were identified and isolated in two-year historical data of total electrical energy consumption.The infrequent electrical load profiles were found to be strongly affected,in terms of both shape and magnitude,by the energy consumption behaviour related to the heating/cooling mechanical room.Then,a fault-free predictive model,which uses artificial neural network(ANN)in combination with a Regression Tree,was developed to detect anomalous trends of the electrical energy consumption.The model was able to detect the 93.7%of the anomalous profiles and only the 5%of fault-free days were wrongly predicted as anomalous.Eventually,a diagnosis phase was conceived and validated with a testing data set.A number of daily abnormal load profiles were detected and compared with the centroids of the anomalous clusters identified in the pattern-recognition stage.The work led to the development of a flexible intelligent tool useful for operating a continuous commissioning of the campus facilities. 展开更多
关键词 anomaly detection data analytics energy management pattern recognition prediction models
高性能标准CMOS传感器应用于3D视觉、感测和度量 认领
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作者 Ha Lan DO THU 易博(译) 《传感器世界》 2021年第1期29-34,共6页
工厂和物流仓库进入自动化年代,带动了高效无人操作工业系统的需求,特别是用于导向机器人和机器(用于物件辨识、导向、高速和精准度)的3D视觉技术。市场上存在多种3D技术,每种各有优缺点和配合技术,大部分取决于应用需求。所有的这些技... 工厂和物流仓库进入自动化年代,带动了高效无人操作工业系统的需求,特别是用于导向机器人和机器(用于物件辨识、导向、高速和精准度)的3D视觉技术。市场上存在多种3D技术,每种各有优缺点和配合技术,大部分取决于应用需求。所有的这些技术都需要具有精密功能的高效传感器。Teledyne e2v包括3D视觉的解决方案系列,以服务诸如工厂自动化、物流和测量。其高性能CMOS影像传感器的技术结合超过10年在飞行时间系统方面的经验,可应对3D视觉方面的种种挑战。 展开更多
关键词 3D视觉 CMOS传感器 飞行时间 感测 度量 检测 机器人 激光三角测量
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针对非洲猪瘟病毒MGF360-13L基因的TaqMan荧光定量PCR的建立 认领
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《中国农业科学》 CAS 北大核心 2021年第5期1073-1080,共8页
【目的】建立一种以MGF360-13L基因为靶标的实时荧光定量PCR检测非洲猪瘟病毒(African swine fever virus,ASFV)的方法,为非洲猪瘟(African swine fever,ASF)的诊断、MGF360-13L基因缺失毒株鉴别、病毒分离鉴定、基因功能研究提供技术... 【目的】建立一种以MGF360-13L基因为靶标的实时荧光定量PCR检测非洲猪瘟病毒(African swine fever virus,ASFV)的方法,为非洲猪瘟(African swine fever,ASF)的诊断、MGF360-13L基因缺失毒株鉴别、病毒分离鉴定、基因功能研究提供技术支持。【方法】首先,以ASFV中国流行毒株(GenBank:MK333180.1)的MGF360-13L基因序列为靶标设计并筛选了1对特异性引物和探针,建立其荧光定量PCR检测方法。设计引物13L-F/13L-R,扩增MGF360-13L,并将其克隆至pOK12载体,挑取阳性克隆并测序验证,构建重组质粒标准品。将重组质粒标准品连续10倍梯度稀释,以稀释后的各梯度质粒标准品为模板,配制反应体系和设置反应条件后进行荧光定量PCR检测,建立标准曲线,并对其敏感性和重复性进行评价;其次,以连续10倍梯度稀释的重组质粒标准品为模板,利用引物13L-F/13L-R进行常规PCR检测,以比较荧光定量PCR的敏感性。最后,运用本检测方法和本研究组已建立的针对ASFV p72的荧光定量PCR检测方法同时对黑龙江某猪场发生ASF时采集的30份临床样品进行检测,以比较两种检测方法的符合率。另外,应用该方法对感染原代巨噬细胞的ASFV野毒株和MGF基因缺失毒株进行鉴别检测。【结果】利用引物13L-F/13L-R可扩增出一条800 bp左右的特异性目的条带,而阴性对照无条带,成功构建出标准品。本研究建立的实时荧光定量PCR检测方法在质粒标准品为1.56×10^(1)-1.56×10^(8)拷贝/μL时,呈现出良好的线性关系,线性回归方程为:y=-3.295 lg(x)+45.995,线性相关系数R2为0.997,对ASFV核酸最低检测限为15.6拷贝/μL。在特异性检验中,除ASFV核酸外,猪瘟病毒、伪狂犬病病毒、猪繁殖与呼吸综合征病毒、猪传染性胃肠炎病毒、猪圆环病毒1型、猪圆环病毒2型等病毒核酸均未出现扩增曲线,表明该方法的特异性良好。与最低检测限为1.56×10^(4)拷贝/μL病毒核酸的常规PC 展开更多
关键词 非洲猪瘟病毒 MGF360-13L 荧光定量PCR 鉴别诊断
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猪α冠状病毒免疫机制及检测技术研究进展 认领
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作者 王烁程 张林波 《动物医学进展》 北大核心 2021年第3期106-110,共5页
猪α冠状病毒可引起猪流行性腹泻,在规模化养猪场中极易传播,以侵害仔猪为主,病死率较高,对养猪产业具有极大危害。研究发现,真核翻译起始因子4-α和25-羟胆固醇(25HC)可能在病毒复制过程中发挥重要作用,猪α冠状病毒编码的核酸核糖内切... 猪α冠状病毒可引起猪流行性腹泻,在规模化养猪场中极易传播,以侵害仔猪为主,病死率较高,对养猪产业具有极大危害。研究发现,真核翻译起始因子4-α和25-羟胆固醇(25HC)可能在病毒复制过程中发挥重要作用,猪α冠状病毒编码的核酸核糖内切酶(EndoU)在病毒逃避宿主先天性免疫防御中起关键作用。近年来,猪α冠状病毒的检测方法在不断更新,如蛋白质芯片技术、高通量实时动态细胞成像及功能分析技术,对于该病的防控具有积极意义。论文对猪α冠状病毒免疫机制及检测方法的研究进展进行综述,以期为猪α冠状病毒研究及相关疾病防控提供参考。 展开更多
关键词 猪冠状病毒 免疫机制 受体 检测
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