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Proceedings of the 2020 9th International Conference on Bioinformatics and Biomedical Science

作者： Imran Javaid Shuai Zhang Abd El Kader Isselmou Souha Kamhi Ummay Kulsum Isah Salim Ahmad Department of Biomedical Engineer Hebei University of Technology 8 Dingzigu 1st Rd Hongqiao China 300131 China

ISBN: (纸本)9781450388658

Brain tumor detection from MRI images is a time consuming and precarious task due to irregular characteristics of tumor tissue image segmentation. In MR images permit convincing evidence and play a decisive part in diagnosing the different kinds of tumors. The segmentation recognition and extraction of tumor area from (MRI) magnetic resonance image are an initial interest. The clinical or radiologist specialists performed a time-consuming and tedious task but their precision relies on their experience. Therefore, the usage of computer-aided expertise becomes mandatory to overcome that limitation. A sophisticated fully automated tumor recognition system is proposed to have the maximum accuracy, specificity and sensitivity with a minimum error rate, computational time and competently extract tumor from MRI images. The current study emphases on tumor and edema segmentation that is built on kernel-based fuzzy C-means and skull stripping method. The clustering method amended by merging multiple kernels established on spatial information. Furthermore, once the acquired image is de-noised the automated brain tumor recognition algorithm stripped the outer boundaries of the irrelevant tissue and then the segmentation algorithm is applied to extract the tumor area precisely. For analysis and recording of the experimental result, hundred MRI images are used. The algorithm in the current study is compared and after the experimental result, the algorithms certify having the detection of brain tumor with accuracy i.e. 98.7%, specificity 90.0%, sensitivity 92.8% with minimum error rate 0.002% given by the improved algorithm KFCM while the minimum computation time i.e. 1.64 seconds achieved by Fuzzy K-means (FKM).

关键词： Automated brain tumor detection Specificity computation time Error rate FKM KFCM Sensitivity Accuracy Skull stripping

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A Fast Rotating Partition Satellite Selection Algorithm Based on Equal Distribution of Sky

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JOURNAL OF NAVIGATION 2019年第4期72卷 1053-1069页

作者： Li, Fangchao Li, Zengke Gao, Jingxiang Yao, Yifei China Univ Min & Technol NASG Key Lab Land Environm & Disaster Monitoring Xuzhou Jiangsu Peoples R China Northwest A&F Univ Coll Water Resources & Architectural Engn Yangling Shaanxi Peoples R China

To achieve fast satellite selection for a multi-Global Navigation Satellite System (GNSS), thereby reducing the burden on a receiver's processing element and the cost of hardware, and improving the utilisation ratio of receiver signal channels, the relationship between the number of satellites and Geometric Dilution Of Precision (GDOP), the number of satellites selected and the computation time is analysed. A fast rotating partition algorithm for satellite selection based on equal distribution of the sky is proposed. The algorithm divides the satellite selection process into two parts: rough selection and detailed selection. Unhealthy satellites, according to a health identifier, and low elevation angle satellites with a large troposphere delay are eliminated during the rough selection process. During the detailed satellite selection process, the satellite sky is divided and rotated to match satellites based on the average angle distance between the satellite and central partition line. Static data from the International GNSS Service (IGS) station and dynamic data collected at China University of Mining and Technology were used to verify the algorithm, and the results demonstrated that an inverse matrix could be avoided to reduce computation complexity. Additionally, the new satellite selection algorithm has the merit that there is little effect on the computation when the selected satellites and number of satellites in the field increased. A single system of the Global Positioning System (GPS) and double system of GPS/Globalnaya Navigazionnaya Sputnikovaya Sistema (GLONASS) both passed the hypothesis test for each epoch. By including BeiDou Navigation Satellite System (BDS) data, data utilisation increased to more than 95% using the rotating partition algorithm. Also, the GDOP and positioning performance of a rotating partition algorithm and an optimal Dilution Of Precision (DOP) algorithm are compared in this paper, and the analysis result shows that both of the a

关键词： Rotating Partition Algorithm GDOP Angle Distance computation time Hypothesis testing Positioning Accuracy

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The value of simplified models for spin up of complex models with an application to subsurface hydrology

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COMPUTERS & GEOSCIENCES 2019年 126卷 62-72页

作者： Erdal, Daniel Baroni, Gabriele Sanchez-Leon, Emilio Cirpka, Olaf A. Univ Tubingen Ctr Appl Geosci Holderlinstr 12 D-72074 Tubingen Germany Univ Potsdam Inst Earth & Environm Sci Karl Liebknecht Str 24-25 D-14476 Potsdam Germany UFZ Helmholtz Ctr Environm Res Dept Computat Hydrosyst Permoserstr 15 D-04318 Leipzig Germany

Spinning up large-scale coupled surface-subsurface numerical models can be a time and resource consuming task. If an uninformed initial condition is chosen, the spin-up can easily require 20 years of repeated simulations on high-performance computing machines. In this paper we compare the classical approach of starting from a fixed shallow depth to groundwater (here 3 m) with three more informed approaches for the definition of initial conditions in the spin up. In the first of these three approaches, we start from a known-steady state groundwater table, calculated with a 2-D groundwater model and the yearly net recharge, and combine it with an unsaturated zone that assumes hydrostatic conditions. In the second approach, we start from the same groundwater table combined with vertical profiles in the unsaturated zone with uniform vertical flow identical to the groundwater recharge. In the third approach we calculate a dynamic steady state from a simplified subsurface model combining a transient 2-D groundwater model with a limited number of 1-D transient unsaturated zone columns on top. Results for spinning-up a 3-D Parflow-CLM model using the different initial conditions show that large gains can be made by considering states in groundwater and the vadose zone that are consistent, i.e. where groundwater recharge and the vertical flux in the vadose zone agree. By this, the spin-up time was reduced from about 10 years to about 3 years of simulated time. In the light of seasonal fluctuations of net recharge, using the transient approach showed more stable results.

关键词： Model spin-up Groundwater-model Unsaturated zone 2.5-D model computation time

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time decomposition strategy for security-constrained economic dispatch

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IET GENERATION TRANSMISSION & DISTRIBUTION 2019年第22期13卷 5129-5138页

作者： Safdarian, Farnaz Kargarian, Amin Louisiana State Univ Dept Elect & Comp Engn Baton Rouge LA 70803 USA

A horizontal time decomposition strategy to reduce the computation time of security-constrained economic dispatch (SCED) is presented in this study. The proposed decomposition strategy is fundamentally novel and is developed in this paper for the first time. The considered scheduling horizon is decomposed into multiple smaller sub-horizons. The concept of overlapping time intervals is introduced to model ramp constraints for the transition from one sub-horizon to another sub-horizon. A sub-horizon includes several internal intervals and one or two overlapping time intervals that interconnect consecutive sub-horizons. A local SCED is formulated for each sub-horizon with respect to internal and overlapping intervals' variables/constraints. The overlapping intervals allow modelling intertemporal constraints between the consecutive sub-horizons in a distributed fashion. To coordinate the subproblems and find the optimal solution for the whole operation horizon distributedly, accelerated auxiliary problem principle is developed. Furthermore, the authors present an initialisation strategy to enhance the convergence performance of the coordination strategy. The proposed algorithm is applied to three large systems, and promising results are obtained.

关键词： power generation scheduling power generation economics scheduling power generation dispatch optimisation power system security overlapping time intervals interconnect consecutive sub-horizons overlapping intervals operation horizon initialisation strategy coordination strategy horizontal time decomposition strategy security-constrained economic dispatch computation time considered scheduling horizon multiple smaller sub-horizons sub-horizon internal intervals

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Real-time approach for oscillatory stability assessment in large-scale power systems based on MRMR classifier

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IET GENERATION TRANSMISSION & DISTRIBUTION 2019年第19期13卷 4431-4442页

作者： Li, Xin Zheng, Zhiyi Ma, Zhicheng Guo, Panfeng Shao, Kaixuan Quan, Siping China Three Gorges Univ Coll Elect Engn & New Energy Yichang Peoples R China China Three Gorges Univ Hubei Prov Key Lab Operat & Control Cascaded Hydr Yichang Peoples R China State Grid State Grid Taizhou Power Supply Co Taizhou Peoples R China

An integrated approach for real-time oscillatory stability assessment (OSA) based on mutual information theory is proposed in this study. An advanced maximum-relevance minimum-redundancy (MRMR) ensemble scheme is designed to explore the internal relations between operation variables and the oscillatory stability margin (OSM). Multiple MRMR procedures are generated in parallel to select multiple different feature subsets, in which each feature presents a relevant and complementary description of OSM. The functional expression of the relationships is obtained by curve fitting. The 21-bus system and 1648-bus system are implemented to test the performance of the proposed approach. A compared investigation is made with some other data mining methods. The impacts of the number of feature sets, size of feature sets, size of training set, invalid data and computation time are studied. Experimental results reveal that the proposed approach provides faster and more accurate assessment results and is a real-time adaptive approach for OSA.

关键词： feature extraction filtering theory information theory pattern classification data mining power system stability time approach large-scale power systems MRMR classifier integrated approach real-time oscillatory stability assessment OSA mutual information theory advanced maximum-relevance minimum-redundancy ensemble scheme internal relations operation variables oscillatory stability margin OSM multiple MRMR procedures multiple different feature subsets relevant description complementary description functional expression 21-bus system 1648-bus system data mining methods feature sets computation time accurate assessment results real-time adaptive approach

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Mapping strategy for virtual networks in one stage

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IET COMMUNICATIONS 2019年第14期13卷 2207-2215页

作者： Cao, Haotong Wu, Shengchen Guo, Yongan Zhu, Hongbo Yang, Longxiang Nanjing Univ Posts & Telecommun Minist Educ Key Lab Broadband Wireless Commun & Sensor Networ Nanjing 210003 Jiangsu Peoples R China Nanjing Univ Posts & Telecommun Jiangsu Key Lab Wireless Commun Nanjing 210003 Jiangsu Peoples R China

In the area of network virtualisation, virtual network embedding (VNE) refers to the resource allocation problem. In the literature, researchers have proposed multiple VNE algorithms. These algorithms have the goal of accommodating as many requested virtual networks (VNs) as possible. However, most of prior embedding algorithms belong to the two-stage (separated node and link embeddings) mapping algorithm category. Certain embedding algorithms embed each VN in one mapping stage by using mixed integer linear programming approach or graph theory, having very high computation time. There is a lack of heuristic algorithms, enabling to embed nodes and links per VN in one mapping stage. In addition, each requested VN embedding needs to be completed in polynomial time so as to be promoted to future dynamic VN service application and real-time VNs embedding. Based on these backgrounds, the authors propose a novel real-time and one-stage heuristic mapping algorithm (VNE-RTOS). Numerical evaluations are conducted to strengthen that VNE-RTOS earns more embedding revenues by 8% over typical two-stage heuristic embedding algorithms (e.g. VNE-TAGRD) while achieving the same substrate resource utilisation.

关键词： computer networks virtualisation embedded systems resource allocation mapping stage network virtualisation resource allocation problem link embeddings mixed integer linear programming approach heuristic algorithms one-stage heuristic mapping algorithm VNE-RTOS embedding revenues two-stage heuristic embedding algorithms VNE algorithms embedding algorithms computation time dynamic VN service application network resources virtual network embedding

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KDFC-ART: a KD-tree approach to enhancing Fixed-size-Candidate-set Adaptive Random Testing

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IEEE TRANSACTIONS ON RELIABILITY 2019年第4期68卷 1444-1469页

作者： Mao, Chengying Zhan, Xuzheng Tse, T. H. Chen, Tsong Yueh Jiangxi Univ Finance & Econ Sch Software & Commun Engn Nanchang 330013 Jiangxi Peoples R China Univ Hong Kong Dept Comp Sci Pokfulam Hong Kong Peoples R China Swinburne Univ Technol Dept Comp Sci & Software Engn Melbourne Vic 3122 Australia

Adaptive random testing (ART) was developed as an enhanced version of random testing to increase the effectiveness of detecting failures in programs by spreading the test cases evenly over the input space. However, heavy computation may be incurred. In this paper, three enhanced algorithms for fixed-size-candidate-set ART (FSCS-ART) are proposed based on the $k$-dimensional tree (KD-tree) structure. The first algorithm Naive-KDFC constructs a KD-tree by splitting the input space with respect to every dimension successively in a round-robin fashion. The second algorithm SemiBal-KDFC improves the balance of the KD-tree by prioritizing the splitting according to the spread in each dimension. In order to control the number of traversed nodes in backtracking, the third algorithm LimBal-KDFC introduces an upper bound for the nodes involved. Simulation and empirical studies have been conducted to investigate the efficiency and effectiveness of the three algorithms. The experimental results show that these algorithms significantly reduce the computation time of the original FSCS-ART for low dimensions and for the case of high dimensions with low failure rates. The efficiency of SemiBal-KDFC is better than that of Naive-KDFC when the dimension is no more than 8, but LimBal-KDFC is the most efficient of all three. Although the limited backtracking leads only to an approximate nearest neighbor in LimBal-KDFC, its failure-detection effectiveness is, in fact, better than FSCS-ART in high-dimensional input spaces and has no significant deterioration in low-dimensional spaces.

关键词： Power capacitors Testing Subspace constraints Software Strips Data structures Aerospace electronics Adaptive random testing (ART) computation time effectiveness efficiency KD-tree software testing test case generation

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Model predictive current control based on a generalised adjacent voltage vectors approach for multilevel inverters

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IET POWER ELECTRONICS 2019年第13期12卷 3590-3599页

作者： Ipoum-Ngome, Paul Gistain Mon-Nzongo, Daniel Legrand Flesch, Rodolfo C. C. Song-Manguelle, Joseph Wang, Mengqi Jin, Tao Fuzhou Univ Elect Engn & Automat Fuzhou 350116 Fujian Peoples R China Pearl Elect Co Ltd Guangzhou 511400 Guangdong Peoples R China Univ Fed Santa Catarina Dept Automat & Syst BR-88040900 Florianopolis SC Brazil Univ Quebec Trois Rivieres Trois Rivieres PQ Canada Univ Michigan Dept Elect & Comp Engn Dearborn MI 48128 USA

Model predictive current control (MPCC) uses the discrete-time model of a system to predict the future behaviour of the current for all voltage vectors (VVs) generated by a power converter. In multilevel inverters, the large number of VVs imposes a long computation time for the prediction and selection of the optimal state to be applied to the converter, which increases the sampling time and decreases the closed-loop performance. An MPCC is proposed based on the idea of generalised adjacent voltage vectors (GAVVs) for multilevel cascaded H-bridge inverters with a DC-link voltage fed by photovoltaic (PV) cells. This method deals with the voltage drop and often small inter-bridge voltage imbalance and irradiance issues that occur in PV power plants. The proposed GAVV method is analytically formulated to provide three types of subsets for a given number of inverter levels. The use of the newly added subsets of four and five VVs contributes to boosting the converter output voltage and achieving acceptably balanced current and line-to-line voltage under low irradiance compared with the classical approach. Simulation and experimental results show good current response and reduced switching frequency even under a high current reference with DC-link voltage drop.

关键词： closed loop systems invertors electric current control power convertors photovoltaic power systems predictive control voltage control current control multilevel inverters MPCC discrete-time model future behaviour sampling time closed-loop performance multilevel cascaded H-bridge inverters photovoltaic cells irradiance issues PV power plants GAVV method inverter levels converter output voltage line-to-line voltage DC-link voltage drop computation time current response current reference interbridge voltage imbalance generalised adjacent voltage vector approach

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A Flux Constrained Predictive Control for a Six-Phase PMSM Motor With Lower Complexity

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IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS 2019年第7期66卷 5081-5093页

作者： Luo, Yixiao Liu, Chunhua City Univ Hong Kong Sch Energy & Environm Hong Kong Peoples R China City Univ Hong Kong Shenzhen Res Inst Shenzhen 518057 Peoples R China

This paper proposes a low-complexity model predictive flux control (MPFC) with current harmonics and torque ripple reduced for a six-phase permanent magnet synchronous machine (PMSM) motor. First, the virtual vectors in two different magnitudes are adopted for the sake of harmonic currents and torque ripple reduction, as well as simplifying the predictive model by eliminating the z(1)-z(2) variables fromthe cost function. Then, a look-up table is developed to exclude the useless voltage vectors in advance. In this way, the number of prediction vectors is reduced and heavy computation burden is alleviated. Moreover, to avoid the tedious tuning work of the weighting factor in the cost function, the torque and flux amplitude are transformed into an equivalent reference flux vector. Thus, the complexity of the cost function is significantly reduced. Meanwhile, the current and torque performance are highly improved using the proposed method. Also, the fast dynamic response of predictive control is retained. Finally, simulation and experimental results are offered to verify the effectiveness of the proposed MPFC method.

关键词： computation time current harmonics model predictive control (MPC) multiphase machine PM machine torque ripple virtual vector weighting factor

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Gabor-based anisotropic diffusion with lattice Boltzmann method for medical ultrasound despeckling

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MATHEMATICAL BIOSCIENCES AND ENGINEERING 2019年第6期16卷 7546-7561页

作者： Xu, Haohao Gong, Yuchen Xia, Xinyi Li, Dong Yan, Zhuangzhi Shi, Jun Zhang, Qi Shanghai Univ Shanghai Inst Adv Commun & Data Sci SMART Smart Med & AI Based Radiol Technol Lab Shanghai 200444 Peoples R China Shanghai Univ Inst Biomed Engn Shanghai 200444 Peoples R China Shanghai Univ Sch Commun & Informat Engn Shanghai 200444 Peoples R China

Medical ultrasound images are corrupted by speckle noise, and despeckling methods are required to effectively and efficiently reduce speckle noise while simultaneously preserving details of tissues. This paper proposes a despeckling approach named the Gabor-based anisotropic diffusion coupled with the lattice Boltzmann method (GAD-LBM), which uses the lattice Boltzmann method (LBM) to fast solve the partial differential equation of an anisotropic diffusion model embedded with the Gabor edge detector. We evaluated the GAD-LBM on both synthetic and clinical ultrasound images, and the experimental results suggested that the GAD-LBM was superior to other nine methods in speckle suppression and detail preservation. For synthetic and clinical images, the computation time of the GAD-LBM was about 1/90 to 1/20 of the GAD solved with the finite difference, indicating the advantage of the GAD-LBM in efficiency. The GAD-LBM not only has excellent ability of noise reduction and detail preservation for ultrasound images, but also has advantages in computational efficiency.

关键词： despeckling Gabor-based anisotropic diffusion lattice Boltzmann method computation time ultrasound

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