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A Novel Cascaded TID-FOI Controller Tuned with Walrus Optimization Algorithm for Frequency Regulation of Deregulated Power System
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作者 Geetanjali Dei Deepak Kumar Gupta +3 位作者 Binod Kumar Sahu Amitkumar V.Jha Bhargav Appasani Nicu Bizon 《Energy Engineering》 2025年第8期3399-3431,共33页
This paper presents an innovative and effective control strategy tailored for a deregulated,diversified energy system involving multiple interconnected area.Each area integrates a unique mix of power generation techno... This paper presents an innovative and effective control strategy tailored for a deregulated,diversified energy system involving multiple interconnected area.Each area integrates a unique mix of power generation technologies:Area 1 combines thermal,hydro,and distributed generation;Area 2 utilizes a blend of thermal units,distributed solar technologies(DST),and hydro power;andThird control area hosts geothermal power station alongside thermal power generation unit and hydropower units.The suggested control system employs a multi-layered approach,featuring a blended methodology utilizing the Tilted Integral Derivative controller(TID)and the Fractional-Order Integral method to enhance performance and stability.The parameters of this hybrid TID-FOI controller are finely tuned using an advanced optimization method known as the Walrus Optimization Algorithm(WaOA).Performance analysis reveals that the combined TID-FOI controller significantly outperforms the TID and PID controllers when comparing their dynamic response across various system configurations.The study also incorporates investigation of redox flow batteries within the broader scope of energy storage applications to assess their impact on system performance.In addition,the research explores the controller’s effectiveness under different power exchange scenarios in a deregulated market,accounting for restrictions on generation ramp rates and governor hysteresis effects in dynamic control.To ensure the reliability and resilience of the presented methodology,the system transitions and develops across a broad range of varying parameters and stochastic load fluctuation.To wrap up,the study offers a pioneering control approach-a hybrid TID-FOI controller optimized via the Walrus Optimization Algorithm(WaOA)-designed for enhanced stability and performance in a complex,three-region hybrid energy system functioning within a deregulated framework. 展开更多
关键词 Integral time multiplied by absolute error(ITAE) load frequency control(LFC) particle swarm optimization(PSO) tilted integral derivative controller(TID) independent system operator(ISO) walrus optimization algorithm(WaOA) proportional integral derivative controller(PID)
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Deep Learning-Based Classification of Rotten Fruits and Identification of Shelf Life
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作者 S.Sofana Reka Ankita Bagelikar +2 位作者 Prakash Venugopal V.Ravi Harimurugan Devarajan 《Computers, Materials & Continua》 SCIE EI 2024年第1期781-794,共14页
The freshness of fruits is considered to be one of the essential characteristics for consumers in determining their quality,flavor and nutritional value.The primary need for identifying rotten fruits is to ensure that... The freshness of fruits is considered to be one of the essential characteristics for consumers in determining their quality,flavor and nutritional value.The primary need for identifying rotten fruits is to ensure that only fresh and high-quality fruits are sold to consumers.The impact of rotten fruits can foster harmful bacteria,molds and other microorganisms that can cause food poisoning and other illnesses to the consumers.The overall purpose of the study is to classify rotten fruits,which can affect the taste,texture,and appearance of other fresh fruits,thereby reducing their shelf life.The agriculture and food industries are increasingly adopting computer vision technology to detect rotten fruits and forecast their shelf life.Hence,this research work mainly focuses on the Convolutional Neural Network’s(CNN)deep learning model,which helps in the classification of rotten fruits.The proposed methodology involves real-time analysis of a dataset of various types of fruits,including apples,bananas,oranges,papayas and guavas.Similarly,machine learningmodels such as GaussianNaïve Bayes(GNB)and random forest are used to predict the fruit’s shelf life.The results obtained from the various pre-trained models for rotten fruit detection are analysed based on an accuracy score to determine the best model.In comparison to other pre-trained models,the visual geometry group16(VGG16)obtained a higher accuracy score of 95%.Likewise,the random forest model delivers a better accuracy score of 88% when compared with GNB in forecasting the fruit’s shelf life.By developing an accurate classification model,only fresh and safe fruits reach consumers,reducing the risks associated with contaminated produce.Thereby,the proposed approach will have a significant impact on the food industry for efficient fruit distribution and also benefit customers to purchase fresh fruits. 展开更多
关键词 Rotten fruit detection shelf life deep learning convolutional neural network machine learning gaussian naïve bayes random forest visual geometry group16
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Prediction of Bandwidth of Metamaterial Antenna Using Pearson Kernel-Based Techniques
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作者 Sherly Alphonse S.Abinaya Sourabh Paul 《Computers, Materials & Continua》 SCIE EI 2024年第3期3449-3467,共19页
The use of metamaterial enhances the performance of a specific class of antennas known as metamaterial antennas.The radiation cost and quality factor of the antenna are influenced by the size of the antenna.Metamateri... The use of metamaterial enhances the performance of a specific class of antennas known as metamaterial antennas.The radiation cost and quality factor of the antenna are influenced by the size of the antenna.Metamaterial antennas allow for the circumvention of the bandwidth restriction for small antennas.Antenna parameters have recently been predicted using machine learning algorithms in existing literature.Machine learning can take the place of the manual process of experimenting to find the ideal simulated antenna parameters.The accuracy of the prediction will be primarily dependent on the model that is used.In this paper,a novel method for forecasting the bandwidth of the metamaterial antenna is proposed,based on using the Pearson Kernel as a standard kernel.Along with these new approaches,this paper suggests a unique hypersphere-based normalization to normalize the values of the dataset attributes and a dimensionality reduction method based on the Pearson kernel to reduce the dimension.A novel algorithm for optimizing the parameters of Convolutional Neural Network(CNN)based on improved Bat Algorithm-based Optimization with Pearson Mutation(BAO-PM)is also presented in this work.The prediction results of the proposed work are better when compared to the existing models in the literature. 展开更多
关键词 ANTENNA pearson optimization BANDWIDTH METAMATERIAL
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Stable switching behavior of low-temperature ZrO_(2)RRAM devices realized by combustion synthesis-assisted photopatterning
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作者 Bongho Jang Junil Kim +2 位作者 Jieun Lee Jaewon Jang Hyuk-Jun Kwon 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第22期68-76,共9页
We have realized efficient photopatterning and high-quality ZrO_(2)films through combustion synthesis and manufactured resistive random access memory(RRAM)devices with excellent switching stability at low temperatures... We have realized efficient photopatterning and high-quality ZrO_(2)films through combustion synthesis and manufactured resistive random access memory(RRAM)devices with excellent switching stability at low temperatures(250℃)using these approaches.Combustion synthesis reduces the energy required for oxide conversion,thus accelerating the decomposition of organic ligands in the UV-exposed area,and promoting the formation of metal-oxygen networks,contributing to patterning.Thermal analysis confirmed a reduction in the conversion temperature of combustion precursors,and the prepared combustion ZrO_(2)films exhibited a high proportion of metal-oxygen bonding that constitutes the oxide lattice,along with an amorphous phase.Furthermore,the synergistic effect of combustion synthesis and UV/O_(3)-assisted photochemical activation resulted in patterned ZrO_(2)films forming even more complete metal-oxygen networks.RRAM devices fabricated with patterned ZrO_(2)films using combustion synthesis exhibited excellent switching characteristics,including a narrow resistance distribution,endurance of 103 cycles,and retention for 105 s at 85℃,despite low-temperature annealing.Combustion synthesis not only enables the formation of high-quality metal oxide films with low external energy but also facilitates improved photopatterning. 展开更多
关键词 ZrO_(2) Combustion SOL-GEL RRAM PATTERNING
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Optimizing Optical Fiber Faults Detection:A Comparative Analysis of Advanced Machine Learning Approaches
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作者 Kamlesh Kumar Soothar Yuanxiang Chen +2 位作者 Arif Hussain Magsi Cong Hu Hussain Shah 《Computers, Materials & Continua》 SCIE EI 2024年第5期2697-2721,共25页
Efficient optical network management poses significant importance in backhaul and access network communicationfor preventing service disruptions and ensuring Quality of Service(QoS)satisfaction.The emerging faultsin o... Efficient optical network management poses significant importance in backhaul and access network communicationfor preventing service disruptions and ensuring Quality of Service(QoS)satisfaction.The emerging faultsin optical networks introduce challenges that can jeopardize the network with a variety of faults.The existingliterature witnessed various partial or inadequate solutions.On the other hand,Machine Learning(ML)hasrevolutionized as a promising technique for fault detection and prevention.Unlike traditional fault managementsystems,this research has three-fold contributions.First,this research leverages the ML and Deep Learning(DL)multi-classification system and evaluates their accuracy in detecting six distinct fault types,including fiber cut,fibereavesdropping,splicing,bad connector,bending,and PC connector.Secondly,this paper assesses the classificationdelay of each classification algorithm.Finally,this work proposes a fiber optics fault prevention algorithm thatdetermines to mitigate the faults accordingly.This work utilized a publicly available fiber optics dataset namedOTDR_Data and applied different ML classifiers,such as Gaussian Naive Bayes(GNB),Logistic Regression(LR),Support Vector Machine(SVM),K-Nearest Neighbor(KNN),Random Forest(RF),and Decision Tree(DT).Moreover,Ensemble Learning(EL)techniques are applied to evaluate the accuracy of various classifiers.In addition,this work evaluated the performance of DL-based Convolutional Neural Network and Long-Short Term Memory(CNN-LSTM)hybrid classifier.The findings reveal that the CNN-LSTM hybrid technique achieved the highestaccuracy of 99%with a delay of 360 s.On the other hand,EL techniques improved the accuracy in detecting fiberoptic faults.Thus,this research comprehensively assesses accuracy and delay metrics for various classifiers andproposes the most efficient attack detection system in fiber optics. 展开更多
关键词 Fiber optics fault detection multiclassification machine learning ensemble learning
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Deep Transfer Learning Techniques in Intrusion Detection System-Internet of Vehicles: A State-of-the-Art Review
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作者 Wufei Wu Javad Hassannataj Joloudari +8 位作者 Senthil Kumar Jagatheesaperumal Kandala N.V.P.SRajesh Silvia Gaftandzhieva Sadiq Hussain Rahimullah Rabih Najibullah Haqjoo Mobeen Nazar Hamed Vahdat-Nejad Rositsa Doneva 《Computers, Materials & Continua》 SCIE EI 2024年第8期2785-2813,共29页
The high performance of IoT technology in transportation networks has led to the increasing adoption of Internet of Vehicles(IoV)technology.The functional advantages of IoV include online communication services,accide... The high performance of IoT technology in transportation networks has led to the increasing adoption of Internet of Vehicles(IoV)technology.The functional advantages of IoV include online communication services,accident prevention,cost reduction,and enhanced traffic regularity.Despite these benefits,IoV technology is susceptible to cyber-attacks,which can exploit vulnerabilities in the vehicle network,leading to perturbations,disturbances,non-recognition of traffic signs,accidents,and vehicle immobilization.This paper reviews the state-of-the-art achievements and developments in applying Deep Transfer Learning(DTL)models for Intrusion Detection Systems in the Internet of Vehicles(IDS-IoV)based on anomaly detection.IDS-IoV leverages anomaly detection through machine learning and DTL techniques to mitigate the risks posed by cyber-attacks.These systems can autonomously create specific models based on network data to differentiate between regular traffic and cyber-attacks.Among these techniques,transfer learning models are particularly promising due to their efficacy with tagged data,reduced training time,lower memory usage,and decreased computational complexity.We evaluate DTL models against criteria including the ability to transfer knowledge,detection rate,accurate analysis of complex data,and stability.This review highlights the significant progress made in the field,showcasing how DTL models enhance the performance and reliability of IDS-IoV systems.By examining recent advancements,we provide insights into how DTL can effectively address cyber-attack challenges in IoV environments,ensuring safer and more efficient transportation networks. 展开更多
关键词 Cyber-attacks internet of things internet of vehicles intrusion detection system
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A Review of the Life Cycle Analysis for Plastic Waste Pyrolysis
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作者 Dounmene Tadida Lhami Arielle Wafula Gerald Nalume Youwene Gilbert 《Open Journal of Polymer Chemistry》 2024年第3期113-145,共33页
Pyrolysis is a rapidly expanding chemical-based recyclable method that complements physical recycling. It avoids improper disposal of post-consumer polymers and mitigates the ecological problems linked to the producti... Pyrolysis is a rapidly expanding chemical-based recyclable method that complements physical recycling. It avoids improper disposal of post-consumer polymers and mitigates the ecological problems linked to the production of new plastic. Nevertheless, while there is a consensus that pyrolysis might be a crucial technology in the years to come, more discussions are needed to address the challenges related to scaling up, the long-term sustainability of the process, and additional variables essential to the advancement of the green economy. Herein, it emphasizes knowledge gaps and methodological issues in current Life Cycle Assessment (LCA), underlining the need for standardized techniques and updated data to support robust decision-making for adopting pyrolysis technologies in waste management strategies. For this purpose, this study reviews the LCAs of pyrolytic processes, encompassing the complete life cycle, from feedstock collection to end-product distribution, including elements such as energy consumption, greenhouse gas emissions, and waste creation. Hence, we evaluate diverse pyrolysis processes, including slow, rapid, and catalytic pyrolysis, emphasizing their distinct efficiency and environmental footprints. Furthermore, we evaluate the impact of feedstock composition, process parameters, and scale of operation on the overall sustainability of pyrolysis-based plastic waste treatment by integrating results from current literature and identifying essential research needs. Therefore, this paper argues that existing LCA studies need more coherence and accuracy. It follows a thorough evaluation of previous research and suggests new insights into methodologies and restrictions. 展开更多
关键词 PLASTICS Thermal Recycling Carbon Dioxide Emissions Life Cycle Evaluation PYROLYSIS
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An Efficient and Accurate Solution for the PnPL Problem
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作者 Ridma Basnayaka Qida Yu 《Instrumentation》 2025年第3期63-75,共13页
Camera Pose Estimating from point and line correspondences is critical in various applications,including robotics,augmented reality,3D reconstruction,and autonomous navigation.Existing methods,such as the Perspective-... Camera Pose Estimating from point and line correspondences is critical in various applications,including robotics,augmented reality,3D reconstruction,and autonomous navigation.Existing methods,such as the Perspective-n-Point(PnP)and Perspective-n-Line(PnL)approaches,offer limited accuracy and robustness in environments with occlusions,noise,or sparse feature data.This paper presents a unified solution,Efficient and Accurate Pose Estimation from Point and Line Correspondences(EAPnPL),combining point-based and linebased constraints to improve pose estimation accuracy and computational efficiency,particularly in low-altitude UAV navigation and obstacle avoidance.The proposed method utilizes quaternion parameterization of the rotation matrix to overcome singularity issues and address challenges in traditional rotation matrix-based formulations.A hybrid optimization framework is developed to integrate both point and line constraints,providing a more robust and stable solution in complex scenarios.The method is evaluated using synthetic and realworld datasets,demonstrating significant improvements in performance over existing techniques.The results indicate that the EAPnPL method enhances accuracy and reduces computational complexity,making it suitable for real-time applications in autonomous UAV systems.This approach offers a promising solution to the limitations of existing camera pose estimation methods,with potential applications in low-altitude navigation,autonomous robotics,and 3D scene reconstruction. 展开更多
关键词 camera pose estimation efficient and accurate pose estimation(eapnpl) UAV navigation obstacle avoidance point-and-line correspondences
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Two-wheeler Helment Wearing Detection Alogrithm Based on Improved YOLOv5
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作者 Xiao Han Xianchun Zhou 《Instrumentation》 2025年第1期11-29,共19页
In many non-motor vehicle traffic accidents in China,the main cause of injury or death for drivers is not wearing a helmet.Therefore,the detection and punishment of such riders hold great significance in protecting pe... In many non-motor vehicle traffic accidents in China,the main cause of injury or death for drivers is not wearing a helmet.Therefore,the detection and punishment of such riders hold great significance in protecting people's lives and property safety.This paper delves into a deep learning-based method for detecting helmet-wearing on electric vehicles.The approach involves studying and designing an improved YOLOv5 model to identify the violation behavior of not wearing a helmet,including inserting the SE module in the network of the visual attention mechanism into the enhanced backbone network;bidirectional feature fusion is significantly enhanced by substituting the concat module with the Bidirectional Feature Pyramid Network(BiFPN)module,and adding receptive field attention Convolution(RFAConv)to the detection head.The improved YOLOv5 model demonstrates a higher mean Average Precision(mAP)while achieving a relatively smaller model size.This method provides technical support for the real-time and accurate detection of non-vehicle helmet targets;its efficacy has been confirmed through analysis of experimental results.These findings suggest that this method can assist traffic management departments in supervising non-motor vehicles,carrying significant practical value and importance. 展开更多
关键词 YOLOv5 Object detection Convolutional neural network RFAConv
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IoT Based Transmission Line Fault Classification Using Regularized RBF-ELM and Virtual PMU in a Smart Grid
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作者 Kunjabihari Swain Murthy Cherukuri +3 位作者 Indu Sekhar Samanta Bhargav Appasani Nicu Bizon Mihai Oproescu 《Computer Modeling in Engineering & Sciences》 2025年第11期1993-2015,共23页
Transmission line faults pose a significant threat to power system resilience,underscoring the need for accurate and rapid fault identification to facilitate proper resource monitoring,economic loss prevention,and bla... Transmission line faults pose a significant threat to power system resilience,underscoring the need for accurate and rapid fault identification to facilitate proper resource monitoring,economic loss prevention,and blackout avoidance.Extreme learning machine(ELM)offers a compelling solution for rapid classification,achieving network training in a single epoch.Leveraging the Internet of Things(IoT)and the virtual instrumentation capabilities of LabVIEW,ELM can enable the swift and precise identification of transmission line faults.This paper presents a regularized radial basis function(RBF)ELM-based fault detection and classification system for transmission lines,utilizing a LabVIEW based virtual phasor measurement unit(PMU)and IoT sensors.The transmission line fault is identified using the phaselet algorithm applied to the phase current acquired from the virtual PMU.Classification is then performed using the ELM algorithm.The proposed methodology is validated in real-time on a practical transmission line,achieving an accuracy of 99.46%.This has the potential to significantly influence future fault detection strategies incorporating virtual PMUs and machine learning. 展开更多
关键词 Phasor measurement units power system protection situational awarenes phaselet fault classification extreme learning machine
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Ethical Principles and Governance Technology Development of AI in China 被引量:12
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作者 Wenjun Wu Tiejun Huang Ke Gong 《Engineering》 SCIE EI 2020年第3期302-309,共8页
Ethics and governance are vital to the healthy and sustainable development of artificial intelligence(AI).With the long-term goal of keeping AI beneficial to human society,governments,research organizations,and compan... Ethics and governance are vital to the healthy and sustainable development of artificial intelligence(AI).With the long-term goal of keeping AI beneficial to human society,governments,research organizations,and companies in China have published ethical guidelines and principles for AI,and have launched projects to develop AI governance technologies.This paper presents a survey of these efforts and highlights the preliminary outcomes in China.It also describes the major research challenges in AI governance research and discusses future research directions. 展开更多
关键词 AI ethical principles AI governance technology Machine learning PRIVACY Safety FAIRNESS
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Application of Electron-Shelving Detection via 423 nm Transition in Calcium-Beam Optical Frequency Standard 被引量:5
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作者 黄凯凯 张建伟 +3 位作者 于得水 陈振辉 庄伟 陈景标 《Chinese Physics Letters》 SCIE CAS CSCD 2006年第12期3198-3201,共4页
A new scheme of small compact optical frequency standard based on thermal calcium beam with application of 423 nm shelving detection and sharp-angle velocity selection detection is proposed. Combining these presented ... A new scheme of small compact optical frequency standard based on thermal calcium beam with application of 423 nm shelving detection and sharp-angle velocity selection detection is proposed. Combining these presented techniques, we conclude that a small compact optical frequency standard based on thermal calcium beam will outperform the commercial caesium-beam microwave dock, like the 5071 Cs clock (from Hp to Agilent, now Symmetricom company), both in accuracy and stability. 展开更多
关键词 SHARP ANGLE INCIDENCE PROBING LASER-BEAM SPECTROSCOPY ATOMS CLOCK
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New Method to Improve Dynamic Stiffness of Electro-hydraulic Servo Systems 被引量:9
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作者 BAI Yanhong QUAN Long 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第5期997-1005,共9页
Most current researches working on improving stiffness focus on the application of control theories.But controller in closed-loop hydraulic control system takes effect only after the controlled position is deviated,so... Most current researches working on improving stiffness focus on the application of control theories.But controller in closed-loop hydraulic control system takes effect only after the controlled position is deviated,so the control action is lagged.Thus dynamic performance against force disturbance and dynamic load stiffness can’t be improved evidently by advanced control algorithms.In this paper,the elementary principle of maintaining piston position unchanged under sudden external force load change by charging additional oil is analyzed.On this basis,the conception of raising dynamic stiffness of electro hydraulic position servo system by flow feedforward compensation is put forward.And a scheme using double servo valves to realize flow feedforward compensation is presented,in which another fast response servo valve is added to the regular electro hydraulic servo system and specially utilized to compensate the compressed oil volume caused by load impact in time.The two valves are arranged in parallel to control the cylinder jointly.Furthermore,the model of flow compensation is derived,by which the product of the amplitude and width of the valve’s pulse command signal can be calculated.And determination rules of the amplitude and width of pulse signal are concluded by analysis and simulations.Using the proposed scheme,simulations and experiments at different positions with different force changes are conducted.The simulation and experimental results show that the system dynamic performance against load force impact is largely improved with decreased maximal dynamic position deviation and shortened settling time.That is,system dynamic load stiffness is evidently raised.This paper proposes a new method which can effectively improve the dynamic stiffness of electro-hydraulic servo systems. 展开更多
关键词 electro-hydraulic servo system flow feedforward compensation dynamic load stiffness double-valve actuation
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Review of chip-scale atomic clocks based on coherent population trapping 被引量:11
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作者 汪中 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第3期47-58,共12页
Research on chip-scale atomic clocks (CSACs) based on coherent population trapping (CPT) is reviewed. The back- ground and the inspiration for the research are described, including the important schemes proposed t... Research on chip-scale atomic clocks (CSACs) based on coherent population trapping (CPT) is reviewed. The back- ground and the inspiration for the research are described, including the important schemes proposed to improve the CPT signal quality, the selection of atoms and buffer gases, and the development of micro-cell fabrication. With regard to the re- liability, stability, and service life of the CSACs, the research regarding the sensitivity of the CPT resonance to temperature and laser power changes is also reviewed, as well as the CPT resonance's collision and light of frequency shifts. The first generation CSACs have already been developed but its characters are still far from our expectations. Our conclusion is that miniaturization and power reduction are the most important aspects calling for further research. 展开更多
关键词 chip-scale atomic clock coherent population trapping
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Thin Film Chip Resistors with High Resistance and Low Temperature Coefficient of Resistance 被引量:5
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作者 王秀宇 张之圣 +1 位作者 白天 刘仲娥 《Transactions of Tianjin University》 EI CAS 2010年第5期348-353,共6页
High resistance thin film chip resistors(0603 type) were studied,and the specifications are as follows:1 k? with tolerance about ±0.1% after laser trimming and temperature coefficient of resistance(TCR) less than... High resistance thin film chip resistors(0603 type) were studied,and the specifications are as follows:1 k? with tolerance about ±0.1% after laser trimming and temperature coefficient of resistance(TCR) less than ±15×10-6/℃.Cr-Si-Ta-Al films were prepared with Ar flow rate and sputtering power fixed at 20 standard-state cubic centimeter per minute(sccm) and 100 W,respectively.The experiment shows that the electrical properties of Cr-SiTa-Al deposition films can meet the specification requirements of 0603 ty... 展开更多
关键词 thin film chip resistor high resistance low temperature coefficient of resistance alloy target magnetic sputtering Cr-Si-Ta-Al film
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Automatic Classification of Cardiac Arrhythmias Based on Hybrid Features and Decision Tree Algorithm 被引量:5
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作者 Santanu Sahoo Asit Subudhi +1 位作者 Manasa Dash Sukanta Sabut 《International Journal of Automation and computing》 EI CSCD 2020年第4期551-561,共11页
Accurate classification of cardiac arrhythmias is a crucial task because of the non-stationary nature of electrocardiogram(ECG)signals.In a life-threatening situation,an automated system is necessary for early detecti... Accurate classification of cardiac arrhythmias is a crucial task because of the non-stationary nature of electrocardiogram(ECG)signals.In a life-threatening situation,an automated system is necessary for early detection of beat abnormalities in order to reduce the mortality rate.In this paper,we propose an automatic classification system of ECG beats based on the multi-domain features derived from the ECG signals.The experimental study was evaluated on ECG signals obtained from the MIT-BIH Arrhythmia Database.The feature set comprises eight empirical mode decomposition(EMD)based features,three features from variational mode decomposition(VMD)and four features from RR intervals.In total,15 features are ranked according to a ranker search approach and then used as input to the support vector machine(SVM)and C4.5 decision tree classifiers for classifying six types of arrhythmia beats.The proposed method achieved best result in C4.5 decision tree classifier with an accuracy of 98.89%compared to cubic-SVM classifier which achieved an accuracy of 95.35%only.Besides accuracy measures,all other parameters such as sensitivity(Se),specificity(Sp)and precision rates of 95.68%,99.28%and 95.8%was achieved better in C4.5 classifier.Also the computational time of 0.65 s with an error rate of 0.11 was achieved which is very less compared to SVM.The multi-domain based features with decision tree classifier obtained the best results in classifying cardiac arrhythmias hence the system could be used efficiently in clinical practices. 展开更多
关键词 Electrocardiogram(ECG) cardiac arrhythmias empirical mode decomposition(EMD) variational mode decomposition(VMD) hybrid features decision tree classifier
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Assessment of cortical bone microdamage following insertion of microimplants using optical coherence tomography: a preliminary study 被引量:4
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作者 Hemanth Tumkur LAKSHMIKANTHA Naresh Kumar RAVICHANDRAN +2 位作者 Mansik JEON Jeehyun KIM Hyo-sang PARK 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2018年第11期818-828,共11页
Objectives: The study was done to evaluate the efficacy of optical coherence tomography (OCT), to detect and analyze the microdamage occurring around the microimplant immediately following its placement, and to com... Objectives: The study was done to evaluate the efficacy of optical coherence tomography (OCT), to detect and analyze the microdamage occurring around the microimplant immediately following its placement, and to compare the findings with micro-computed tomography (IJCT) images of the samples to validate the result of the present study. Methods: Microimplants were inserted into bovine bone samples. Images of the samples were obtained using OCT and μCT. Visual comparisons of the images were made to evaluate whether anatomical details and microdamage induced by microimplant insertion were accurately revealed by OCT. Results: The surface of the cortical bone with its anatomical variations is visualized on the OCT images. Microdamage occurring on the surface of the cortical bone around the microimplant can be appreciated in OCT images. The resulting OCT images were compared with the μCT images. A high correlation regarding the visualization of individual microcracks was observed. The depth penetration of OCT is limited when compared to μCT. Conclusions: OCT in the present study was able to generate high-resolution images of the microdamage occurring around the microimplant. Image quality at the surface of the cortical bone is above par when compared with μCT imaging, because of the inherent high contrast and high-resolution quality of OCT systems. Improvements in the imaging depth and development of intraoral sensors are vital for developing a real-time imaging system and integrating the system into orthodontic practice. 展开更多
关键词 Optical coherence tomography Microimplant Cortical bone Micro-computed tomography
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Construction of LDPC Codes for the Layered Decoding Algorithm 被引量:4
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作者 Wang Da Dong Mingke +2 位作者 Chen Chen Jin Ye Xiang Haige 《China Communications》 SCIE CSCD 2012年第7期99-107,共9页
Abstract: The layered decoding algorithm has been widely used in the implementation of Low Density Parity Check (LDPC) decoders, due to its high convergence speed. However, the pipeline operation of the layered dec... Abstract: The layered decoding algorithm has been widely used in the implementation of Low Density Parity Check (LDPC) decoders, due to its high convergence speed. However, the pipeline operation of the layered decoder may introduce memory access conflicts, which heavily deteriorates the decoder throughput. To essentially deal with the issue of memory access conflicts, 展开更多
关键词 LDPC codes construction algorithm PEG algorithm layered decoding algorithm memory access conflicts
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Effect of concentration of cadmium sulfate solution on structural,optical and electric properties of Cd_(1-x)Zn_(x)S thin films 被引量:4
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作者 Yuming Xue Shipeng Zhang +4 位作者 Dianyou Song Liming Zhang Xinyu Wang Lang Wang Hang Sun 《Journal of Semiconductors》 EI CAS CSCD 2021年第11期26-31,共6页
Cd_(1-x)Zn_(x)S thin films were deposited by chemical bath deposition(CBD)on the glass substrate to study the influence of cadmium sulfate concentration on the structural characteristics of the thin film.The SEM resul... Cd_(1-x)Zn_(x)S thin films were deposited by chemical bath deposition(CBD)on the glass substrate to study the influence of cadmium sulfate concentration on the structural characteristics of the thin film.The SEM results show that the thin film surfaces under the cadmium sulfate concentration of 0.005 M exhibit better compactness and uniformity.The distribution diagrams of thin film elements illustrate the film growth rate changes on the trend of the increase,decrease,and increase with the increase of cadmium sulfate concentration.XRD studies exhibit the crystal structure of the film is the hexagonal phase,and there are obvious diffraction peaks and better crystallinity when the concentration is 0.005 M.Spectrophotometer test results demonstrate that the relationship between zinc content x and optical band gap value E_(g) can be expressed by the equation E_(g)(x)=0.59x^(2)+0.69x+2.43.Increasing the zinc content can increase the optical band gap,and the absorbance of the thin film can be improved by decreasing the cadmium sulfate concentration,however,all of them have good transmittance.At a concentration of 0.005 M,the thin film has good absorbance in the 300-800 nm range,80%transmittance,and band gap value of 3.24 eV,which is suitable for use as a buffer layer for solar cells. 展开更多
关键词 CIGS thin film solar cell CBD(chemical bath deposition) buffer layer Cd_(1-x)Zn_(x)S thin films cadmium sulfate
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Automated Segmentation of Left Ventricle Using Local and Global Intensity Based Active Contour and Dynamic Programming 被引量:3
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作者 G.Dharanibai Anupama Chandrasekharan Zachariah C.Alex 《International Journal of Automation and computing》 EI CSCD 2018年第6期673-688,共16页
The aim of this work is to develop an improved region based active contour and dynamic programming based method for accurate segmentation of left ventricle (LV) from multi-slice cine short axis cardiac magnetic reso... The aim of this work is to develop an improved region based active contour and dynamic programming based method for accurate segmentation of left ventricle (LV) from multi-slice cine short axis cardiac magnetic resonance (MR) images. Intensity inhomogeneity and weak object boundaries present in MR images hinder the segmentation accuracy. The proposed active contour model driven by a local Gaussian distribution fitting (LGDF) energy and an auxiliary global intensity fitting energy improves the accuracy of endocardial boundary detection. The weightage of the global energy fitting term is dynamically adjusted using a spatially varying weight function. Dynamic programming scheme proposed for the segmentation of epicardium considers the myocardium probability map and a distance weighted edge map in the cost matrix. Radial distance weighted technique and conical geometry are employed for segmenting the basal slices with left ventricle outflow tract (LVOT) and most apical slices. The proposed method is validated on a public dataset comprising 45 subjects from medical image computing and computer assisted interventions (MICCAI) 2009 segmentation challenge. The average percentage of good endocardial and epicardial contours detected is about 99%, average perpendicular distance of the detected good contours from the manual reference contours is 1.95 mm, and the dice similarity coefficient between the detected contours and the reference contours is 0.91. Correlation coefficient and the coefficient of determination between the ejection fraction measurements from manual segmentation and the automated method are respectively 0.9781 and 0.9567, for LV mass these values are 0.9249 and 0.8554. Statistical analysis of the results reveals a good agreement between the clinical parameters determined manually and those estimated using the automated method. 展开更多
关键词 Cardiovascular magnetic resonance left ventricle ENDOCARDIUM EPICARDIUM MYOCARDIUM segmentation active contour dynamic programming.
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