84 results on '"Yang Gu"'
Search Results
2. Research on Remote Meterage and Monitoring Method for AC Charging Pile of Electric Vehicle
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Ya-Jun, Wang, primary, Yang, GU, additional, Lei, Zhang, additional, and Yan, Huang, additional
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- 2022
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3. Intermittent dynamic event-triggered control for linear system with quantized input
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Yang Gu and Mouquan Shen
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- 2022
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4. Optimized Computation Combining Classification and Detection Networks with Distillation
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Meng Xu, Stefan Poslad, Yang Gu, and Shiqing Xue
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Artificial neural network ,Computer science ,Object (computer science) ,computer.software_genre ,Convolutional neural network ,Object detection ,law.invention ,Reduction (complexity) ,Resource (project management) ,law ,Network performance ,Data mining ,Distillation ,computer - Abstract
A Convolutional neural network (CNN) has emerged as a widely used approach to computer vision tasks, including object classification and detection tasks. The high requirement for the model to be more computationally efficient on lower information and communication technology (ICT) resource, e.g., mobile terminals can benefit from model distillation. However, most existing distillation methods suffer from a significant accuracy reduction, which requires a large number of pre-training models or doesn't make good use of the more of the network information, e.g., in the middle layers, during the distillation. In this paper, we study how knowledge about traffic signs recognition could be transferred to smaller models by distillation while cutting channels. We present an optimized object detection network, which uses a Region Proposal Network (RPN) weighted loss and hard-soft distribution-wise distillation loss for structural differences between teacher and student networks. We validate the network on multiple real-world datasets, the experiments demonstrate that the classification accuracy can be improved by 9 % with about 16 times parameter reduction while the detection network performance could be increased by 10.6% using an optimized object detection network.
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- 2021
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5. Control of unknown mismatched uncertainties by event-triggered schemes
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Yang Gu and Mouquan Shen
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Scheme (programming language) ,Computer science ,010401 analytical chemistry ,Linear system ,Control (management) ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Control theory ,Bounded function ,0210 nano-technology ,computer ,Event triggered ,computer.programming_language - Abstract
This paper is concerned with the event-triggered control problem of unknown mismatched time-varying uncertainties. Three event-triggered schemes, namely, the absolute scheme, the relative scheme, and the switching scheme, are proposed to reduce the unnecessary signal transmission. A backstepping-like design approach is employed to cope with the mismatched time-varying uncertainties. Consequently, the proposed controllers could compensate for the mismatched time-varying uncertainties and ensure the closed-loop system globally bounded. The validity of the proposed schemes is shown by an illustrative example.
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- 2020
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6. Highly Fluent Sign Language Synthesis Based on Variable Motion Frame Interpolation
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Xing Yunbing, Yang Gu, Yiqiang Chen, Dongdong Liu, and Ni Zeng
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Computer science ,business.industry ,Mean opinion score ,Frame (networking) ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Optical flow ,020207 software engineering ,02 engineering and technology ,Sign language ,Chinese Sign Language ,Convolutional neural network ,language.human_language ,0202 electrical engineering, electronic engineering, information engineering ,language ,020201 artificial intelligence & image processing ,Computer vision ,Artificial intelligence ,Motion interpolation ,business - Abstract
Sign Language Synthesis (SLS) is a domain-specific problem where multiple sign language words are stitched to generate a whole sentence in video, which serves to facilitate communications between the hearing-impaired people and healthy population. This paper presents a Variable Motion Frame Interpolation (VMFI) method for highly fluent SLS in scattered videos. Existing approaches for SLS mainly focus on mechanical virtual human technology, lacking high flexibility and natural effect. Also, the representative solutions to interpolate frames usually assume that the motion object moves at a constant speed which is not suitable for predicting the complex hand motion in frames of scattered sign language videos. To address the above issues, the proposed VMFI adopts acceleration to predict more accurate interpolated frames based on an end-to-end convolutional neural network. The framework of VMFI consists of variable optical flow estimation network and high-quality frame synthesis network that can approximate and fuse the intermediate optical flow to generate interpolated frames for synthesis. Experimental results on our realistic collected Chinese sign language dataset demonstrate that the proposed VMFI model achieves efficiency by performing better in PSNR (Peak Signal to Noise Ratio), SSIM (Structural Similarity) and MA (Motion Activity) and gets higher score in MOS (Mean Opinion Score) than other two representative methods.
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- 2020
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7. Consistent Assessment of Microwave Scattering and Vertical Dynamic Characteristics in the Precipitation Environment Over Oceans
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Yuxuan Feng, Jieying He, Gang Ma, Jing Huang, Jingyang Li, Yang Guo, Guiqing Liu, Peng Zhang, and Jiandong Gong
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Consistency assessment ,dynamic analysis ,FY-3E MWTS-III ,microwave precipitation detection ,microwave scattering ,Ocean engineering ,TC1501-1800 ,Geophysics. Cosmic physics ,QC801-809 - Abstract
To improve the assimilation accuracy of satellite microwave observations, it is necessary to conduct precipitation detection before assimilation and exclude the data contaminated by the scattering of hydromorphic particles. The induction of microwave scattering is closely related to the effective radius of hydromorphic particles, and the motion state of hydromorphic particles at different scales can directly affect the internal dynamic structure of clouds, which will lead to precipitation. To further analyze and validate the impact of microwave scattering in a precipitation environment on the assimilation of satellite microwave soundings within the temperature-sensitive band, this article utilized the on-orbit observations of Microwave Temperature Sounder-III (MWTS-III) and Medium Resolution Spectral Imager onboard the Fengyun-3E (FY-3E) satellite to achieve multispectral fusion observation and precipitation detection over oceans, combined with the vertical dynamic characteristics of global numerical forecast in the cloud environment of China Meteorological Administration (CMA) Global Forecast System (CMA-GFS). By conducting the dynamic analysis of the hydrometeors in the cloud, the maximum possible effective particle radius of hydromorphic particles under the no-phase-transition condition and internal vertical motion is obtained. The consistency of the cloud liquid water path (CLWP) retrieved by MWTS-III and multispectral fusion precipitation detection is evaluated subsequently. The results show that the distribution of hydrometeors in the CMA-GFS forecast is broadly in line with the CLWP distribution obtained from the MWTS-III retrieval, regardless of Mie scattering or Rayleigh scattering. However, compared with Mie scattering, the weak convection of CMA-GFS shows better adaptability in the Rayleigh environment.
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- 2024
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8. Research on Encounter Probability Between a Supercavitating Vehicle and a Target Based on Path Planning
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Yang Guang, Lu Faxing, Xu Junfei, Wu Ling, and Li Yiyuan
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Supercavitating vehicle ,encounter probability ,path planning ,Monte Carlo method ,law of error propagation ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
Supercavitating vehicles have received significant attention in military applications due to their high underwater speed. This paper aims to establish analytic models of the encounter probability between a supercavitating vehicle and its target in two modes: straight-running mode (SRM) and turning-straight-running mode (TSRM). Mathematical models for the supercavitating vehicle to encounter the target in SRM and TSRM are proposed. An improved particle swarm optimization (PSO) algorithm based on local best topology with a penalty function is introduced to plan the TSRM path of the supercavitating vehicle. The particle swarm position is updated by using Cauchy and Gaussian distributions. The judgement indexes of the encounter probability analytic models in SRM and TSRM are determined through statistical analysis. Based on the law of error propagation, the analytic models of judgement index variances in the two modes are derived by using the implicit function differential method, and the integral intervals of their probability density functions are obtained according to the relative motion between the supercavitating vehicle and the target. Monte Carlo simulations and hypothesis testing are utilized to verify the accuracy and feasibility of the encounter probability analytic models in SRM and TSRM.
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- 2024
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9. CoFINLo: Coarse to Fine Indoor Navigation and Localization System
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Tong Wu, Yiqiang Chen, Yunlong Xiao, Yang Gu, Jiwei Wang, and Xinlong Jiang
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050101 languages & linguistics ,Computer science ,05 social sciences ,Feature extraction ,Real-time computing ,02 engineering and technology ,Interaction design ,Coarse to fine ,Wireless signal ,0202 electrical engineering, electronic engineering, information engineering ,Key (cryptography) ,Trajectory ,020201 artificial intelligence & image processing ,0501 psychology and cognitive sciences ,Incremental build model ,Localization system - Abstract
Services based on indoor navigation and localization play crucial roles in people's daily life, and they are even more important for individuals with visual impairments. In this paper, an indoor navigation and localization system CoFINLo with three key techniques: 1) dynamic feature extraction, 2) incremental model update, and 3) fine-grained trajectory generation, is proposed to implement robust indoor localization with friendly interaction design especially for visual impairment groups. Compared with other indoor localization systems, the proposed CoFINLo can overcome the obstacles caused by the diverse sensing devices, complex indoor environments, and fluctuated wireless signal. The proposed system is verified in an indoor office environment and implemented in a large-scale and comprehensive train station. The average 1.39m localization error suggests that CoFINLo can open a new opportunity to implement robust and user-friendly indoor navigation and localization in large and complex indoor environments, which can be a solid foundation for other location-based services.
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- 2019
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10. Indoor Trajectory Restoration Method Based on PoI Relation Constraints
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Yang Gu, Yiqiang Chen, Junfa Liu, Xinlong Jiang, and Xing Yunbing
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050101 languages & linguistics ,Relation (database) ,Computer science ,Location model ,05 social sciences ,Nonlinear dimensionality reduction ,02 engineering and technology ,Semi-supervised learning ,computer.software_genre ,Constraint (information theory) ,Robustness (computer science) ,0202 electrical engineering, electronic engineering, information engineering ,Trajectory ,020201 artificial intelligence & image processing ,0501 psychology and cognitive sciences ,Data mining ,Multidimensional scaling ,computer - Abstract
User's position and trajectory are very important personal informations, based on which, the user's personalized description can be realized, and the user's intentions, preferences and behavior patterns can also be found. For most of traditional approaches, the trajectory learning problems assume the availability of a vast amount of labeled training data, which requires a great deal of manual effort. In this paper we propose a indoor trajectory restoration method based on the spatial constraints on the position of points of interests (PoI). This method discovers PoI position by detecting the status changing of furniture and facilities and constructs spatial relationship of PoI positions with multidimensional scaling (MDS). Then, it synthetically optimizes the location model constructing of fitting error to labeled points, the manifold regularization of high-dimensional signal strength vectors and the MDS constraint of the spatial relationship of PoI positions, to achieve the optimizing trajectory by iteration. The experimental results show that our proposed method can effectively improve the robustness of the trajectory learning ability in different practical scenarios, benefiting from the constraint of PoI position.
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- 2019
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11. A Collaborative Multi-modality Selection Method Based on Data Utility Assessment
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Yunlong Xiao, Tong Wu, Jiwei Wang, and Yang Gu
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050101 languages & linguistics ,Modalities ,SIMPLE (military communications protocol) ,business.industry ,Computer science ,media_common.quotation_subject ,Noise reduction ,05 social sciences ,02 engineering and technology ,Machine learning ,computer.software_genre ,Field (computer science) ,Modal ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,0501 psychology and cognitive sciences ,Quality (business) ,Artificial intelligence ,business ,computer ,Selection (genetic algorithm) ,Data selection ,media_common - Abstract
Multimodal fusion is more and more widely used in the field of machine learning, but it faces a prominent problem in practical application: data utility is not stable. The data of different modalities may be missing and noisy randomly, which will interfere the machine learning model of multi-modal fusion. Most of the existing multi-modal fusion methods neglect data utility problems or only adopt simple data denoising methods to improve data utility. To solve the problem of unstable data utility, we propose a data selection method based on the evaluation of data utility. By training a special machine learning model, the optimal modal combination is predicted according to the quality evaluation of multi-modal data samples to accomplish the dynamic selection of data modalities. The experimental results show that the proposed method can effectively improve the accuracy of multi-modal recognition under low data utility.
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- 2019
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12. Coherent Detection of Terahertz Waves with a Gas Plasma
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Xin-Yang Gu, Jinsong Liu, and Kejia Wang
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Materials science ,Optics ,Field (physics) ,Terahertz radiation ,business.industry ,Gas plasma ,Physics::Optics ,High voltage ,Plasma ,business ,Beam (structure) - Abstract
We demonstrate an alternative coherent detection technique via terahertz induced second-harmonic (TISH) in a laser-induced plasma for terahertz waves. In this method, the probe beam requires neither high voltage bias nor optically field bias.
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- 2018
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13. SensoryGANs: An Effective Generative Adversarial Framework for Sensor-based Human Activity Recognition
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Haonan Pan, Yunlong Xiao, Yiqiang Chen, Yang Gu, and Jiwei Wang
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Ubiquitous computing ,Process (engineering) ,Computer science ,business.industry ,Wearable computer ,02 engineering and technology ,010501 environmental sciences ,Machine learning ,computer.software_genre ,01 natural sciences ,Field (computer science) ,Data modeling ,Activity recognition ,Software deployment ,020204 information systems ,0202 electrical engineering, electronic engineering, information engineering ,Artificial intelligence ,business ,computer ,Generative grammar ,0105 earth and related environmental sciences - Abstract
This study focuses on improving the performance of human activity recognition when a small number of sensor data are available under some special practical scenarios and resource-limited environments, such as some high-risk projects, anomaly monitoring and actual tactical scenarios. The Human Activity Recognition (HAR) based on wearable sensors is an attractive research topic in machine learning and ubiquitous computing over the last few decades, and has extremely practicality in health surveillance, medical assistance, personalized services, etc. However, with the limitation of sensor sampling rate, sustainability, deployment, and other restricted conditions, it is difficult to collect enough and resultful sensor data anywhere, anytime. Therefore, the HAR based on wearable sensors always faces the challenges of the low-data regime under some practical scenarios, which leads to a low accuracy of activity recognition and needs to be solved urgently. Currently, the Generative Adversarial Networks (GANs) provide a powerful method for training resultful generative models that could generate very convincing verisimilar images. The framework of GANs and its variants shed many lights on improving the performance of HAR. In this paper, we propose a new generative adversarial networks framework called SensoryGANs that can effectively generate available sensor data used for HAR. To the best of our knowledge, SensoryGANs is the first unbroken generative adversarial networks applied in generating sensor data in the HAR research field. Firstly, we tried exploring and devising three activity-special GANs models for three human daily activities. Secondly, these specific models are trained with the guidance of unbroken vanilla GANs. Thirdly, the trained generators from adversarial optimization process are used to generate synthetic sensor data. Finally, the synthetic sensor data from SensoryGANs are used to enrich the original authentic sensor datasets, which can improve the performance of target activity recognition model. Meanwhile, we propose three visual evaluation methods for assessing synthetic sensor data produced by the trained generators in SensoryGANs models. Experimental results show that SensoryGANs models have the capability of capturing the implicit distribution of real sensor data of human activity, and then the synthetic sensor data generated by SensoryGANs models Have a potential for improving human activity recognition.
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- 2018
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14. An On-Site Metering Device for Electric Vehicle DC Charging Point
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Yan Liu, Hejun Yao, Yang Gu, Yan Huang, and Tingting Kang
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business.product_category ,Comparator ,business.industry ,Computer science ,Electric potential energy ,020208 electrical & electronic engineering ,Electrical engineering ,020302 automobile design & engineering ,02 engineering and technology ,Signal ,0203 mechanical engineering ,Interference (communication) ,Power module ,Electric vehicle ,0202 electrical engineering, electronic engineering, information engineering ,Measurement uncertainty ,Metering mode ,business - Abstract
This paper describes an on-site metering device for electric vehicle DC charging point. The device realizes the measurement of high DC current by using DC comparator. Every part in power module is isolated with each other for reducing interference. Meanwhile, GNSS signal reception module is added for time metering. The device is portable for metering on-site, and the measurement range of DCV is 3V~900V, while DCI is 0.5A ~300A. The measurement results show that the DC electrical energy error of this device is below 0.05%, and the stability is better than 0.007%/min.
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- 2018
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15. An interacting multiple model filtering method aided by radial velocity information
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RunZhi Jiao, Yang Gu, Jian Wang, and Song Qian
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Radar tracker ,Computer science ,Mathematical analysis ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Filter (signal processing) ,Tracking (particle physics) ,law.invention ,Radial velocity ,Hardware_GENERAL ,law ,Position (vector) ,Cartesian coordinate system ,Astrophysics::Earth and Planetary Astrophysics ,Polar coordinate system ,Radar ,ComputingMethodologies_COMPUTERGRAPHICS - Abstract
In this paper, we propose an interacting multiple model filtering algorithm aided by radar radial velocity information (RVIMM). This algorithm introduces the concept of “take-credit factor”, which is adopted to solve the problem that the radial velocity of the maneuvering target in polar coordinates cannot be linearly represented by the target states in Cartesian coordinates. By using the “take-credit factor”, a weighted sum of the estimated radial velocity and other states of the target can improve the prediction process of the radial velocity. Finally, the radial velocity of the tracking filter is unified into a single framework. The simulation results show that the proposed algorithm is well-performed on radial velocity estimation, and the estimation for other target states including model probability, position and velocity are more accurate with radial velocity.
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- 2018
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16. Trajectory initialization foot-mounted IMU and calibration using a and UWB anchors
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Zhimin Zhou, Yang Gu, Qian Song, and Ming Ma
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Inertial frame of reference ,Computer science ,business.industry ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Initialization ,ComputerApplications_COMPUTERSINOTHERSYSTEMS ,Pedestrian ,Computer Science::Multiagent Systems ,Inertial measurement unit ,Robustness (computer science) ,Dead reckoning ,Computer vision ,Artificial intelligence ,Particle filter ,business ,Search and rescue - Abstract
Inertial based pedestrian positioning is very useful in emergency response situations, such as search and rescue (SAR) missions as it is independent of external infrastructures and signals. Two practical problems emerge in inertial based pedestrian positioning: trajectory initialization and trajectory calibration. The former one denotes how to determine the initial position and heading of the pedestrian, and the latter denotes how to reduce the dead reckoning (DR) errors due to inertial drifts. This paper provides a solution to these two problems adopting a few ultra-wide band (UWB) anchors, which can provide range measurements between the anchors and the pedestrian. The foundation of the method is graph based simultaneously localization and mapping (SLAM). The nodes in the graph are the poses of the pedestrian and the edges are the range measurements between the UWB anchors and the tags mounted on the pedestrian. Both simulations and real scenario experiments are carried out to validate the proposed method. The proposed approach outperformed the particle filtering based approach in terms of robustness and processing time.
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- 2018
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17. Wide-Angle Scanning Phased Array Antenna
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Ji, Bowen, primary and Yang, Gu, additional
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- 2019
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18. Game theory based distributed energy trading for microgrids parks
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Fook Hoong Choo, Tianyang Zhao, Peng Wang, Longqi Zhang, and Yang Gu
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Mathematical optimization ,business.industry ,Computer science ,Market clearing ,Supply and demand ,symbols.namesake ,Distributed algorithm ,Nash equilibrium ,Best response ,Distributed generation ,symbols ,Uniqueness ,business ,Game theory - Abstract
To realize the energy sharing among multiple microgrids (MGs) within MG parks, a non-cooperative game based distributed trading is proposed. A linear supply and demand market clearing mechanism is proposed for energy prosumers. A day-ahead energy trading problem is proposed for each MG, correlated with other MGs' trading plans in the utility function. A non-cooperative game is formulated for the energy trading competition among MGs. The existence and uniqueness of Nash equilibrium (NE) corresponding to the proposed game is verified from the perspective of potential games. Based on best response functions, a globally converged distributed algorithm is adopted to compute the NE. The simulation is carried out on the MG park with three MGs. Results have verified the proposed method can obtain an efficient NE where MGs act as prosumers.
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- 2017
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19. WiFi based trajectory alignment, calibration and crowdsourced site survey using smart phones and foot-mounted IMUs
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Caifa Zhou, Andreas Wieser, Zhimin Zhou, and Yang Gu
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Matching (graph theory) ,business.industry ,Computer science ,RSS ,010401 analytical chemistry ,Coordinate system ,020206 networking & telecommunications ,02 engineering and technology ,computer.file_format ,Simultaneous localization and mapping ,01 natural sciences ,0104 chemical sciences ,Error function ,Units of measurement ,0202 electrical engineering, electronic engineering, information engineering ,Trajectory ,Graph (abstract data type) ,Computer vision ,Artificial intelligence ,business ,computer - Abstract
Foot-mounted inertial positioning (FMIP) can face problems of inertial drifts and unknown initial states in real applications, which renders the estimated trajectories inaccurate and not obtained in a well defined coordinate system for matching trajectories of different users. In this paper, an approach adopting received signal strength (RSS) measurements for Wifi access points (APs) are proposed to align and calibrate the trajectories estimated from foot mounted inertial measurement units (IMUs). A crowdsourced radio map (RM) can be built subsequently and can be used for fingerprinting based Wifi indoor positioning (FWIP). The foundation of the proposed approach is graph-based simultaneously localization and mapping (SLAM). The nodes in the graph denote users' poses and the edges denote the pairwise constrains between the nodes. The constrains are derived from: (1) inertial estimated trajectories; (2) vicinity in the RSS space. With these constrains, an error functions is defined. By minimizing the error function, the graph is optimized and the aligned/calibrated trajectories along with the RM are acquired. The experimental results have corroborated the effectiveness of the approach for trajectory alignment, calibration as well as RM construction.
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- 2017
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20. Pedestrian positioning using WiFi fingerprints and a foot-mounted inertial sensor
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Yang Gu, Caifa Zhou, Zhimin Zhou, and Andreas Wieser
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FOS: Computer and information sciences ,Inertial frame of reference ,Computer science ,business.industry ,Fingerprint recognition ,Statistics - Applications ,Signal ,Term (time) ,Consistency (database systems) ,symbols.namesake ,symbols ,Trajectory ,Applications (stat.AP) ,Computer vision ,Artificial intelligence ,business ,Particle filter ,Gaussian process ,Simulation - Abstract
Foot-mounted inertial positioning (FMIP) and fingerprinting based WiFi indoor positioning (FWIP) are two promising solutions for indoor positioning. However, FMIP suffers from accumulative positioning errors in the long term while FWIP involves a very labor-intensive offline training phase. A new approach combining the two solutions is proposed in this paper, which can limit the error growth in FMIP and is free of any offline site survey phase. This approach is realized in the framework of a particle filter, where each particle denotes a potential trajectory of the user and is weighted according to its consistency in signal strength space. Compared with the traditional Gaussian process based approaches, the proposed one has less computational cost and is free from any prior information in the position domain, such as the positions of access points, received signal strengths at certain positions and so on. An experiment is carried out to demonstrate the performance of the proposed approach compared to the traditional Gaussian process based approach., Comment: 12 figures. Accepted by European Navigation Conference 2017, Lausanne
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- 2017
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21. Monolithic Yb-Doped Femtosecond Fiber Laser With >300 W Average Power
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Chenyang Gao, Yang Gui, Yandang Wang, Xianming Zhang, Gengji Zhou, Meng Pang, Jianwu Ding, and Yuxin Leng
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Fiber optics systems ,pulse compression ,ultrafast lasers ,Applied optics. Photonics ,TA1501-1820 ,Optics. Light ,QC350-467 - Abstract
In this submission, we report a maximum 638-W fiberized chirped-pulse-amplification (CPA) laser system with a bulk reflection grating compressor. The system is able to emit 338-W compressed pulses of 624 fs centered at 1 µm, corresponding to a pulse energy of 1.3 µJ at a pulse repetition rate of 258 MHz. The output beam quality factor M2 is measured to be
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- 2023
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22. An anchor based framework for trajectory calibration in inertial pedestrian positioning systems
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Yang Gu, Qian Song, Ming Ma, Yanghuan Li, and Zhimin Zhou
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Engineering ,Inertial frame of reference ,business.industry ,010401 analytical chemistry ,Constraint (computer-aided design) ,020206 networking & telecommunications ,Control engineering ,Ranging ,02 engineering and technology ,Pedestrian ,01 natural sciences ,0104 chemical sciences ,Control theory ,ComputerApplications_MISCELLANEOUS ,0202 electrical engineering, electronic engineering, information engineering ,Trajectory ,Calibration ,Particle filter ,business ,Expansive - Abstract
To tackle the error accumulation problems of the foot-mounted inertial positioning systems, aiding measurements are often adopted to calibrate the inertial-generated raw trajectories. Currently, the calibration methods, although effective, still lack interior connection and unity. In this paper, a unified anchor based trajectory calibration framework is proposed. The concept of anchors is defined as different types of aiding information and is considered as different constraint conditions to the inertial-generated trajectory. The foundation of the framework is a particle filter, and different anchor information correspond to different particle weight updating strategy. The proposed framework is expansive to incorporated different types of anchors. We choose three representative anchors to elaborate the proposed framework and they are: Ultra-WideBand (UWB) ranging anchors, iBeacons and the building structure based virtual anchors. The results in simulations and real scenario tests have validated the effectiveness of the proposed anchor based framework in calibrating the inertial-generated raw trajectories.
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- 2016
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23. A heading error estimation approach based on improved Quasi-static magnetic Field detection
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Yang Gu, Qian Song, Ming Ma, Zhimin Zhou, and Yanghuan Li
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Inertial frame of reference ,Positioning system ,Magnetometer ,Computer science ,020208 electrical & electronic engineering ,010401 analytical chemistry ,Perturbation (astronomy) ,02 engineering and technology ,01 natural sciences ,0104 chemical sciences ,law.invention ,Magnetic field ,Extended Kalman filter ,Control theory ,law ,0202 electrical engineering, electronic engineering, information engineering ,False alarm ,Inertial navigation system - Abstract
The Zero-velocity Update (ZUPT)-aided Extended Kalman Filter(EKF) algorithm is commonly used to suppress the error growth of the inertial based pedestrian navigation systems, but it still suffers from long-term heading drift. The magnetic field was suggested to mitigate the heading errors of for positioning and navigation, but it undergoes severe perturbation in indoor scenarios. The Quasi-Static magnetic Field (QSF) method was developed to estimate heading errors using magnetic field in perturbed environments. However, this method may bring extra errors to system because of the high false alarm probability of detecting the quasi-static field. In this paper, we propose a heading error estimation approach based on the improved QSF approach for foot-mounted Inertial Navigation Systems (INS). For the approach, a magnetometer calibration method is developed to eliminate the deviation caused by the positioning system platform and shoes firstly. Then an improved QSF detection approach is proposed and then used for generating the desired magnetic measurements which are fed into the EKF to estimate the heading errors. The experiments indicate that the proposed method is effective in suppressing the heading errors.
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- 2016
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24. Near Real Time Heading Drift Correction for indoor pedestrian tracking based on sequence detection
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Yang-huan Li, Qian Song, Ming Ma, and Yang Gu
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Engineering ,Heading (navigation) ,Sequence ,Inertial frame of reference ,Orientation (computer vision) ,business.industry ,Heuristic ,010401 analytical chemistry ,Gyroscope ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Tracking (particle physics) ,01 natural sciences ,0104 chemical sciences ,law.invention ,Set (abstract data type) ,law ,Computer vision ,Artificial intelligence ,0210 nano-technology ,business - Abstract
Foot-mounted inertial sensor is a practical and efficient approach for indoor personnel positioning, because it requires neither pre-deployed infrastructure nor on-line “fingerprint” database. To suppress the heading drift of gyroscopes, magnetic field is often used as a stable orientation reference. But the magnetic field inside buildings changes rapidly while space and time changes, and it is also sensitive to some metal objects or electrical equipments. Thanks to the regular structures of most buildings, Heuristic Drift Elimination (HDE) techniques can be applied to suppress slowing-changed small-scale drifts between two steps, under the assumption that most of the paths in the buildings consist of straight lines and fixed angles. Inspired by the heuristic method, a Near Real-Time Heading Drift Correction (NRHDC) approach is proposed in this paper, which determines the current walking behavior based on the steps foregoing and following. Different step status are set to classify each step and different templates are trained for walking behavior discrimination. This approach is supposed to exploit more information and give more precise result. The experimental results in a building also demonstrate the effectiveness of the proposed approach, with superior accuracy to other methods.
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- 2016
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25. Novel hybrid modulation based isolated high-frequency bidirectional inverter for microgrid application
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Akshay Kumar Rathore, Yang Gu, Xuewei Pan, and Peng Wang
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Electrolytic capacitor ,Engineering ,business.industry ,020208 electrical & electronic engineering ,02 engineering and technology ,Low frequency ,Energy storage ,DC-BUS ,Line (electrical engineering) ,Modulation ,0202 electrical engineering, electronic engineering, information engineering ,Electronic engineering ,Inverter ,Microgrid ,business - Abstract
This paper presents a novel hybrid modulation method based isolated high frequency (HF) bidirectional inverter for AC microgrid application. Bidirectional current-fed converter has been employed to interface the energy storage and intermediate fluctuating dc bus. A new hybrid modulation techniques consisting of fluctuating-dc-modulation (FDM) at low frequency (LF) scale and secondary modulation (SM) at HF scale has been proposed for the current-fed converter. The zero current soft switching (ZCS) of primary side devices and zero voltage soft switching (ZVS) of secondary side devices of front-end current-fed full-bridge converter is realized. The back-end full bridge inverter has been utilized to interface the fluctuating dc bus and AC microgrid. A rotating partial hybrid pulsewidth modulation (RP-HPWM) has been introduced. One leg of inverter is commutated at low switching frequency while the other leg is operated at high switching frequency for partial period of line frequency cycle. Besides the high switching frequency operated switches are only commutated at low value of current flowing through them. Thus, switching losses of the back-end inverter can be considerably reduced. Rotating mechanism is used to equalize the switching losses of four switches of the inverter. The low frequency (LF) fluctuating dc bus allows the reduction of dc-link electrolytic capacitor. This paper presents operation and analysis of the complete inverter topology implementing the proposed hybrid modulation scheme. Simulation results using PSIM9.0.4 and experimental results from a lab prototype clearly validate effectiveness of the proposed modulation scheme.
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- 2016
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26. Using iBeacons for trajectory initialization and calibration in foot-mounted inertial pedestrian positioning systems
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Zhimin Zhou, Qian Song, Ming Ma, Yanghuan Li, and Yang Gu
- Subjects
Computer science ,business.industry ,Calibration (statistics) ,010401 analytical chemistry ,Initialization ,020206 networking & telecommunications ,02 engineering and technology ,01 natural sciences ,0104 chemical sciences ,iBeacon ,Noise ,symbols.namesake ,0202 electrical engineering, electronic engineering, information engineering ,Trajectory ,symbols ,Range (statistics) ,Computer vision ,Artificial intelligence ,Particle filter ,business ,Gaussian process - Abstract
In foot-mounted positioning systems, it is hard to align multi-agent trajectories. In addition, the positioning accuracy is hard to maintain due to inertial drifts. An approach for trajectory initialization and calibration using iBeacons is proposed in this paper. This approach is under the framework of a particle filter. In the observation model of the particle filter, a nonparametric Gaussian Process (GP) regression model is adopted to describe the relationship between the estimated range and the observed RSS. Then the weights of the particles are updated according to the trained GP. GP is adopted here because it not only considers the sensor noise, but also the uncertainty in the model, which denotes the multi-path effects, human sheltering effects and so on in receiving the iBeacon signals. At last, a large-scale real-scenario experiment is carried out with a total walking length of about 5.4 kilometers. The results have demonstrated the effectiveness of the proposed approach for trajectory initialization and calibration, with the final positioning error reduced from 85.4 meters to only less than 1meter.
- Published
- 2016
- Full Text
- View/download PDF
27. Novel hybrid modulation based isolated high-frequency three-phase bidirectional inverter for fuel cell vehicles
- Author
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Xuewei Pan, Peng Wang, Akshay Kumar Rathore, and Yang Gu
- Subjects
Engineering ,business.industry ,020208 electrical & electronic engineering ,Electrical engineering ,High voltage ,02 engineering and technology ,DC-BUS ,law.invention ,Capacitor ,Three-phase ,law ,Modulation ,Power electronics ,0202 electrical engineering, electronic engineering, information engineering ,Electronic engineering ,Inverter ,business ,Pulse-width modulation - Abstract
This paper presents a six-pulse low frequency (LF) fluctuating high voltage dc bus based power system architecture for the fuel cell vehicles (FCVs) application. A novel hybrid modulation techniques consisting of six-pulse modulation (SPM) at LF scale and secondary modulation and 33% sine pulse width modulation (33% SPWM) at high frequency (HF) scale. Three-phase ac waveforms are produced for the propulsion system in FCVs. It significant reduces the switching losses of the bidirectional dual-stage inverter: 1) the zero current soft switching (ZCS) of primary side devices and zero voltage soft switching (ZVS) of secondary side devices of front-end current-fed full-bridge converter is realized. 2) at any moment, only one leg of back-end 3-phase inverter is switched at HF while the other two legs are kept in on or off state. This tremendously reduces the bidirectional inverter's switching losses and improves the system efficiency. Besides, switching loss can be further reduced since all the inverter switches are switched at the low current range. The LF fluctuating high voltage dc bus allows the elimination of large electrolytic dc-link capacitor. This paper presents the operation, analysis, and design of a bidirectional inverter implementing the proposed hybrid modulation technique. Simulation results obtained from power electronics simulation software PSIM and experimental results from the lab prototype clearly validate the effectiveness of the proposed modulation technique.
- Published
- 2016
- Full Text
- View/download PDF
28. Heterogeneous Data Driven Manifold Regularization Model for Fingerprint Calibration Reduction
- Author
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Zhiqi Shen, Xinlong Jiang, Yang Gu, Yiqiang Chen, Junfa Liu, and Lisha Hu
- Subjects
Computer science ,Calibration (statistics) ,Node (networking) ,02 engineering and technology ,Semi-supervised learning ,computer.software_genre ,Data-driven ,Data modeling ,Reduction (complexity) ,020204 information systems ,Location-based service ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,Data mining ,Wireless sensor network ,computer - Abstract
Accurate indoor localization is very important for various kinds of Location Based Services (LBS). For most of traditional approaches, the location estimation problems assume the availability of a vast amount of labeled calibrated data, which requires a great deal of manual effort. Previous researches cannot deal with this problem in both calibration reduction, location accuracy. In this paper, we propose a heterogeneous data driven manifold regularization model known as HeterMan to calibration-effort reduction for tracking a mobile node in a wireless sensor network. With the constraint of user heading orientation, we build a mapping function between signal space, physical space with extremely less labeled data, a large amount of unlabeled data. Experimental results show that we can achieve high accuracy with extremely less calibration effort comparing with previous methods. Furthermore, our method can reduce computation complexity, time consumption by parallel processing while maintaining high accuracy.
- Published
- 2016
- Full Text
- View/download PDF
29. Second-order sliding-mode control of synchronous buck converter based on sub-optimal algorithm
- Author
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Songbin, Liu, primary, Zhiyuan, Feng, additional, Yang, Gu, additional, Hai, Koh Leong, additional, and Peng, Wang, additional
- Published
- 2017
- Full Text
- View/download PDF
30. A new method to measure millivolt ac voltage at frequencies up to 200 kHz
- Author
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Deshi Zhang, Yang Gu, Wenfang Liu, Hongtao Huang, Xianlin Pan, and Jiangtao Zhang
- Subjects
Materials science ,business.industry ,Voltage divider ,Electrical engineering ,Measure (physics) ,Electronic engineering ,Volt ,Voltage regulator ,business ,Current divider ,AC/AC converter ,Voltage - Published
- 2014
- Full Text
- View/download PDF
31. A new method to compare two thermal current converters at common ground at frequency up to 200 kHz
- Author
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Wenfang Liu, Xianlin Pan, Jiangtao Zhang, Yang Gu, Hongtao Huang, and Deshi Zhang
- Subjects
Engineering ,business.industry ,Thermal ,Electrical engineering ,Electronic engineering ,Common ground ,Current (fluid) ,Converters ,business - Published
- 2014
- Full Text
- View/download PDF
32. Robinia-BLAST: An Extensible Parallel BLAST Based on Data-Intensive Distributed Computing
- Author
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Zhenchun Huang and Yang Gu
- Subjects
Speedup ,Sequence database ,business.industry ,Computer science ,Computation ,Suite ,Distributed computing ,ComputerApplications_COMPUTERSINOTHERSYSTEMS ,ComputingMethodologies_PATTERNRECOGNITION ,Hotspot (Wi-Fi) ,Parallel processing (DSP implementation) ,Scalability ,The Internet ,business - Abstract
BLAST[1] (Basic Local Alignment Search Tool) is a suite of programs used to identify similarity between genetic sequences. It is one of the most widely used tools in Bioinformatics. In recent years, with the size of gene and protein sequence database increasing exponentially, BLAST has become both a data-intensive and a computation-intensive application. How to run BLAST rapidly with low cost has always been the hotspot to researchers. Parallelization is one of the most important ways to resolve this problem. In this paper, a new approach for parallelizing BLAST based on a parallel processing framework called Robinia is presented. Compared with parallel version of BLAST presented before, Robinia-based BLAST has easy public accessibility and good scalability. Most importantly, it can support operation on WAN, this make it possible to integrate computation and storage resources on Internet to service for super-large scale BLAST projects. We implemented the Robinia-based BLAST and experimented on it using two different datasets. The results show that parallel BLAST based on Robinia can achieve linear speedup based on number of used nodes with good scalability and low cost.
- Published
- 2014
- Full Text
- View/download PDF
33. Constraint Online Sequential Extreme Learning Machine for lifelong indoor localization system
- Author
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Junfa Liu, Yiqiang Chen, Xinlong Jiang, and Yang Gu
- Subjects
Constraint (information theory) ,Online sequential ,Computer science ,Real-time computing ,SIGNAL (programming language) ,Location-based service ,Contrast (statistics) ,Localization system ,Simulation ,Field (computer science) ,Extreme learning machine - Abstract
As an important technology in LBS (Location Based Services) field, Wi-Fi based indoor localization suffers signal fluctuation problem which prevents lifelong and high performance running. With the fluctuation of wireless signal over time, fingerprints collected at the same location become different; therefore existing model cannot fit the new collected data well, which decreases the localization accuracy. In this paper, a novel indoor localization method COSELM (Constraint Online Sequential Extreme Learning Machine) is proposed, utilizing incremental data to update the old model and overcome the fluctuation problem. The performance of COSELM is validated in real Wi-Fi indoor environment. Compared with OSELM, it can improve more than 5% localization accuracy on average; and in contrast to batch learning, COSELM can save more than 50% time consumption.
- Published
- 2014
- Full Text
- View/download PDF
34. Accurate height estimation based on apriori knowledge of buildings
- Author
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Yang Gu, Ming Ma, Yang-huan Li, and Qian Song
- Subjects
Extended Kalman filter ,Stairs ,Computer science ,law ,Control theory ,Heuristic (computer science) ,A priori and a posteriori ,Gyroscope ,Hidden Markov model ,Accelerometer ,Barometer ,law.invention - Abstract
For Search and Rescue (SAR) applications in large buildings, vertical accuracy may seem to be more important than horizontal accuracy, because correctness of floor estimation is mission critical. In this paper, an approachfor height error suppression based on apriori knowledge is proposed, which focuses on long-term height drift suppression along with proper floor determination. An Extended Kalman Filter (EKF) algorithm is firstly reviewed, which integrates barometer data to correct height drift brought by gyroscopes and accelerometers. However, height drift caused by barometer is still unacceptable in a long-term duration. So a new method is proposed under the assumption that a person's height only changes on stairs in the building. Based on this assumption, the whole course of walking in a building is partitioned into floor phase and stair phase, according to a built HMM model. Height estimation can be corrected by considering apriori knowledge of buildings, and will be performed following different rules in the two phases. For the floor phase, the height remains consistent on the same floor, and minor drifts are suppressed inspired by Heuristic Drift Elimination (HDE). For the stair phase, after sufficient stair-related information is acquired, a Maximum Likelihood Estimation (MLE) method is used to estimate the height of each stair step, and drift-free height difference between two floors can be estimated using the estimated stair step height. The experimental results of the proposed approach demonstrate the effectiveness of the approach for height error suppression in SAR use with forced ventilation and sudden change in air pressure.
- Published
- 2013
- Full Text
- View/download PDF
35. Coordinating large-scale wind integration and transmission planning
- Author
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James D. McCalley, Yang Gu, and Ming Ni
- Subjects
Investment decisions ,Wind power ,Operations research ,Transmission (telecommunications) ,Scale (ratio) ,Renewable Energy, Sustainability and the Environment ,business.industry ,Computer science ,Computation ,Transmission system ,business ,Investment (macroeconomics) ,Energy (signal processing) - Abstract
In this paper, a generation expansion planning model and a transmission expansion planning model are proposed to inform investment decisions from the perspectives of generation companies and ISOs, respectively. Interactions between large-scale wind integration and transmission system planning are analyzed, and a new computational procedure of system expansion planning that coordinates generation and transmission investment is presented. The cooptimization of energy and ancillary services markets is considered to capture the impacts of wind power on the operation of the electric system. Benders decomposition is employed to reduce the overall computation time.
- Published
- 2013
- Full Text
- View/download PDF
36. Quantifying the benefits of energy and ancillary services market
- Author
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Zheng Zhou, Rui Bo, Lynn Hecker, Jie Yan, James Okullo, and Yang Gu
- Subjects
Power system simulation ,Production cost ,Value proposition ,Value (economics) ,Economic dispatch ,Energy market ,Business ,Environmental economics ,Energy (signal processing) ,Scheduling (computing) - Abstract
This paper presents a methodology to quantify the economic benefits of having centralized energy market and ancillary services market. A long-term production cost simulation model, which performs security-constrained unit commitment (SCUC) and security-constrained economic dispatch (SCED), is employed to simulate the operating conditions of the system with and without the energy and ancillary services market. The proposed methodology is used in the Midwest Independent Transmission System Operator, Inc. (MISO)'s Value Proposition study, which looks into the value provided by MISO to its market participants and their customers.
- Published
- 2013
- Full Text
- View/download PDF
37. A novel market simulation methodology on hydro storage
- Author
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Yang Gu, Zheng Zhou, Dale Osborn, and Jordan Bakke
- Subjects
Power system simulation ,business.industry ,Computer data storage ,Eastern Interconnection ,Economic dispatch ,Energy market ,Bidding ,Market simulation ,Environmental economics ,business ,Economic benefits - Abstract
This paper presents a simulation methodology that evaluates the economic performance of hydro storage system in the day-ahead (DA) and real-time (RT) markets. A detailed hydro storage system model is proposed to capture the unique characteristics of hydro storage units. A long-term production cost simulation model is employed which performs chronological hourly Security-Constrained Unit Commitment (SCUC) and Security-Constrained Economic Dispatch (SCED) and cooptimizes both the energy market and the ancillary services market. Three MH RT bidding strategies are proposed to represent how MH bids to the RT market. A unique RT market bidding method named Tiered Bidding is proposed to represent hydro storage units' RT market offer curves. The proposed methodology is applied to the Eastern Interconnection system to evaluate the economic benefits of Manitoba Hydro's active market participation in MISO's RT energy and ancillary services market.
- Published
- 2013
- Full Text
- View/download PDF
38. A new congested flowgate ranking strategy in MISO Market Efficiency Planning Study
- Author
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Liangying Hecker, Ming Ni, Jordan Bakke, Yang Gu, James Okullo, and Rui Bo
- Subjects
Cost allocation ,Index (economics) ,Operations research ,Ranking ,Computer science ,Planning study ,Market efficiency ,Task (project management) - Abstract
In MISO Market Efficiency Planning Study, a critical task is to pick from congested flowgates the ones that have the most potential economic benefits. A new ranking strategy, Estimated Potential Benefit (EPB), is proposed. To compare the performance of the new proposed ranking strategy with commonly used ones, ranking correctness index is introduced as a quantitative measure. EPB not only has the most comparable physical meaning to the actual potential benefit, but also has been verified to outperform other ranking strategies, especially when only the very top ranked flowgates are to be picked.
- Published
- 2013
- Full Text
- View/download PDF
39. Control method of rotation angular position zero point transition of stabilization platform framework
- Author
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Jie Xu and Yang Gu
- Subjects
Intelligent sensor ,Control theory ,Robustness (computer science) ,Angular displacement ,Computer science ,Zero-point energy ,Digital control ,Angular velocity ,Particle detector ,Control methods - Abstract
For the zero point transition issues affecting the of the stabilization platform framework when running a wide rotating range, the principle of the rotation angular position measuring is introduced and the reasons leading to zero point transition phenomenon are analyzed. Based on distinguishing the relationship between the zero point and the zero site, the zero point transition counter method is proposed for intelligent measurement and controller designing to help completing the platform framework running a wide rotating range with high precision. This method employs only angular position measuring values instead of angular velocity values to solve the problem of zero point transition, and also avoids the sampling data inconsistencies of the multi-loop digital control system. The experimental results show that after the method processing, the high-precision stabilization platform can complete the rotation by commands with a strong robustness and anti-interference ability in the complex work environment applications.
- Published
- 2012
- Full Text
- View/download PDF
40. Determination of the equivalent inductance of current shunts
- Author
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Jiangtao Zhang, Yan Huang, Yang Gu, Deshi Zhang, and Xianlin Pan
- Subjects
Physics ,business.industry ,Equivalent series inductance ,Mathematical analysis ,Time constant ,Electrical engineering ,Substitution method ,law.invention ,Inductance ,law ,Standard uncertainty ,Current (fluid) ,Resistor ,business - Abstract
This paper describes the determination of the equivalent inductance of current shunts from 1 A to 10 A at the frequency from 50 kHz to 200 kHz. The equivalent inductances were measured against a set of four-terminal resistor whose time constants were precisely known. The standard uncertainty was evaluated to be within 0.03 nH.
- Published
- 2012
- Full Text
- View/download PDF
41. Transmission expansion planning considering economic and reliability criteria
- Author
-
Rui Bo, Ming Ni, and Yang Gu
- Subjects
Electric power transmission ,Investment decisions ,Transmission (telecommunications) ,Operations research ,Computer science ,Investment (macroeconomics) ,Economic benefits ,Reliability (statistics) - Abstract
This paper presents a transmission expansion planning model which combines the advantages of both the traditional reliability-based transmission planning model and economic (also known as value-based, economics-based, or market-based) transmission planning model. Reliability-based transmission planning tries to install new lines at minimal cost while fulfilling system reliability criteria. Economic transmission planning, on the other hand, seeks investment opportunities so that network expansions can generate more economic benefits than the costs. Benders decomposition technique is employed to separate the planning problem into one master problem, which makes investment decisions, and two sets of sub-problems, which evaluate the reliability and economic performance of the electric system, respectively. The proposed model is illustrated on a 5-bus system.
- Published
- 2012
- Full Text
- View/download PDF
42. Congested flowgates ranking analysis and a potential new approach
- Author
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Rui Bo, Ming Ni, and Yang Gu
- Subjects
Mathematical optimization ,Engineering ,Correctness ,Ranking ,business.industry ,Shadow price ,Rank (computer programming) ,Process (computing) ,Production (economics) ,Sample (statistics) ,business ,Reliability engineering ,Rank correlation - Abstract
Congested flowgate ranking is a process to rank flowgates by the potential benefits associated with each flowgate when it is relieved. The rank can be used to help identify top congested flowgates for full evaluation and planning. Ideally, congested flowgates should be ranked by their potential benefits when congestion is relieved individually. This approach however requires one change case simulation for each flowgate and creates significant computation burden. It is desirable to develop metrics solely based on information from base case simulation and use the metrics to get approximate rank. Two metrics, annual shadow price and annual congestion cost, are used in the industry to rank the congested flowgates. No analysis has yet been done to compare these two metrics. This paper compares these two metrics by using different measures. Measures such as data correlation, rank correlation, rank correctness count and percentage are proposed to evaluate the goodness-of-fit of the ranks produced by the two metrics with respect to the actual rank. Sample data from MISO Top Congested Flowgates Study are used in this analysis. As neither of the metrics has been justified in producing a good rank, a new approach is explored. The feasibility is exemplified through a 5-bus test system study. The new approach is potentially capable of estimating actual benefit in a more accurate and computational efficient manner.
- Published
- 2012
- Full Text
- View/download PDF
43. Analysis and simulation of inverter employing SiC Schottky diode
- Author
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Hongliang Lu, Yang Gu, Yimen Zhang, Renxu Jia, and Yuming Zhang
- Subjects
Materials science ,business.industry ,PIN diode ,Schottky diode ,Backward diode ,Flyback diode ,law.invention ,law ,Optoelectronics ,Inverter ,business ,Varicap ,Diode ,Step recovery diode - Abstract
The effect of the diode reverse recovery on the performance of inverters is analyzed. The PSpice simulation of the SPWM full bridge inverter has been performed with the Si p-i-n ultra fast diode and the SiC Schottky diode respectively used as the free wheeling diode under the same condition. With their comparison, the results show that the SiC Schottky diode can greatly reduce the power loss of inverters. Further more, the effects of diode parameter CJO on reverse recovery characteristics have been discussed.
- Published
- 2011
- Full Text
- View/download PDF
44. Compressed air energy storage: State space modeling and performance analysis
- Author
-
James D. McCalley, Venkat Krishnan, Trishna Das, and Yang Gu
- Subjects
Engineering ,Compressed air energy storage ,State-space representation ,GeneralLiterature_INTRODUCTORYANDSURVEY ,business.industry ,Atmospheric model ,Automotive engineering ,Wind variability ,Work (electrical) ,State space ,Electricity ,business ,Simulation based ,Simulation - Abstract
Compressed Air Energy Storage (CAES) has been touted as the next generation bulk storage technology that is capable of effectively addressing the wind variability issue, and provide flexible and economic generation. This work develops a state space model for CAES that enables to monitor the dynamic status of the CAES storage module. The developed state space model is used to design a simulation based tool that assesses various CAES configurations' operational and economic performance for a specific geography.
- Published
- 2011
- Full Text
- View/download PDF
45. Market-based transmission expansion planning
- Author
-
Yang Gu and James D. McCalley
- Subjects
Market based ,Microeconomics ,Electric power system ,Operations research ,Transmission (telecommunications) ,media_common.quotation_subject ,Scalability ,Market efficiency ,Economics ,Benders' decomposition ,Payment ,Reliability (statistics) ,media_common - Abstract
This paper presents a market-based transmission expansion planning model and compares it with a traditional reliability-based transmission planning model. Reliability-based transmission planning tries to install new lines at minimal cost while fulfilling system reliability criteria. Market-based transmission planning, on the other hand, seeks investment opportunities so that network expansions can generate more economic benefits than the costs. Benders decomposition technique is employed in both methods, and their master problems and slave problems are compared, respectively. The two models are applied on a five-bus system and a thirty-bus system. The results show that the market-based transmission planning method is better in terms of relieving system congestions, enhancing market efficiency and reducing load payments. The scalability of the market-based transmission planning algorithm is also discussed in this paper.
- Published
- 2011
- Full Text
- View/download PDF
46. Market-based transmission expansion planning under uncertainty
- Author
-
James D. McCalley and Yang Gu
- Subjects
Investment decisions ,Wind power ,Operations research ,Transmission (telecommunications) ,Computer science ,business.industry ,Monte Carlo method ,Electricity market ,Common value auction ,Robustness testing ,Decomposition method (constraint satisfaction) ,business ,Simulation - Abstract
This paper presents a market-based transmission expansion planning model, which seeks to find investment opportunities that will bring more economic benefits than the costs. Benders decomposition method is used to decompose the whole planning problem into a master problem, which makes investment decisions, and a slave problem, which simulates the operation of the electric market. Uncertainties appearing in the planning process are analyzed systematically and classified into random and non-random uncertainties. Monte Carlo simulation method is applied to simulate random uncertainties, while robustness testing method is employed to incorporate nonrandom uncertainties. The case study illustrates the application of the proposed model in a competitive electricity market with double-sided auctions.
- Published
- 2010
- Full Text
- View/download PDF
47. National long-term investment planning for energy and transportation systems
- Author
-
Arun K. Somani, Robert C. Brown, James D. McCalley, Konstantina Gkritza, Dionysios C. Aliprantis, Yang Gu, Lizhi Wang, and Eduardo Ibanez
- Subjects
Transportation planning ,Engineering ,business.industry ,media_common.quotation_subject ,Evolutionary algorithm ,Energy planning ,Flow network ,Transport engineering ,Interdependence ,Work (electrical) ,Risk analysis (engineering) ,Sustainability ,Software design ,business ,media_common - Abstract
The most significant energy consuming infrastructures and the greatest contributors to greenhouse gases in the US today are electric and freight/passenger transportation systems. Technological alternatives for producing, transporting, and converting energy for electric and transportation systems are numerous. Selecting from among them requires long-term assessment since these capital-intensive infrastructures take years to build with lifetimes approaching a century. The advent of electrified transportation creates interdependencies between the two infrastructures that may be both problematic and beneficial. We are developing modeling capability to perform long-term electric/transportation infrastructure design at a national level, accounting for their interdependencies. The approach combines network flow/DC-flow modeling with a multiobjective solution method. We motivate the need for this work by summarizing attributes and issues related to the investment planning problem so as to find minimum-cost, low-emission, resilient infrastructure portfolios for the future. State-of-the-art energy planning models are summarized, and we describe our software design which includes a multiobjective evolutionary algorithm with a network linear programming cost minimization fitness evaluation, together with metrics for evaluating resiliency and sustainability.
- Published
- 2010
- Full Text
- View/download PDF
48. Learning tactic-based motion models with fast particle smoothing
- Author
-
Manuela Veloso and Yang Gu
- Subjects
Robot kinematics ,State variable ,Engineering ,business.industry ,Mobile robot ,Autonomous robot ,Computer Science::Robotics ,Control theory ,Video tracking ,Robot ,Computer vision ,Artificial intelligence ,business ,Particle filter ,Smoothing - Abstract
Learning parameters of a motion model is an important challenge for autonomous robots. We address the particular instance of parameter learning when tracking motions with a switching state-space model. We present a general algorithm for dealing simultaneously with both unknown fixed model parameters and state variables. Using an Expectation-Maximization approach, we apply a tactic-based multi-model particle filter to estimate the state variables in the E-step, and use particle smoothing to update the parameters in the M-step. We test our algorithm both in simulation and in a team robot soccer environment, as a substrate for applying the learned models to object tracking in a team. One of the soccer robots learns the actuation model of its teammate. The experimental results show that the particle smoothing efficiency is substantially increased and the tracking performance is significantly improved using the learned teammate actuation model.
- Published
- 2008
- Full Text
- View/download PDF
49. Learning Tactic-Based Motion Models of a Moving Object with Particle Filtering
- Author
-
Manuela Veloso and Yang Gu
- Subjects
Robot kinematics ,business.industry ,Computer science ,Mobile robot ,Object (computer science) ,Tracking (particle physics) ,Computer Science::Robotics ,Video tracking ,Robot ,Computer vision ,Artificial intelligence ,business ,Particle filter ,Dynamic Bayesian network - Abstract
Learning motion models of a moving object is a challenge for autonomous robots. We address the particular instance of parameter learning when tracking object motions in a switching multi-model system. We present a general algorithm of joint parameter-state estimation based on multi-model particle filter. We apply the approach to a specific ball-tracking problem and extend the algorithm to learn model parameters in a dynamic Bayesian network (DBN). We show empirical results in simulation and in a team robot soccer environment, as a substrate for applying the learned models to object tracking in a team. The learning capability allow the tracker to much more effectively track mobile objects.
- Published
- 2007
- Full Text
- View/download PDF
50. Team-Driven Multi-Model Motion Tracking with Communication
- Author
-
Yang Gu and Manuela Veloso
- Subjects
Personal robot ,Engineering ,Social robot ,business.industry ,Mobile robot ,Robotics ,Robot learning ,Robot control ,Match moving ,Human–computer interaction ,Robot ,Computer vision ,Artificial intelligence ,business - Abstract
Interactions are frequently seen between the robot and the targets being tracked within the robotics community. Modeling the interactions using knowledge of robot cognition improves the performance of the tracker. Communication improves the performance of a multi-agent system. The focus of this paper is to present our solution to integrate the communication information into our team-driven multi-model motion tracking. We present the probabilistic tracking algorithm in detail and present empirical results both in simulation and in a Segway soccer team. The information from team communication allows the robot to much more effectively track mobile targets.
- Published
- 2006
- Full Text
- View/download PDF
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