Browsing University of Hertfordshire by Author "Helian, Na"

Now showing items 1-20 of 28

    • Anovel HEOMGA Approach for Class Imbalance Problem in the Application of Customer Churn Prediction 

      AlShourbaji, Ibrahim; Helian, Na; Sun, Yi; Alhameed, Mohammed (2021-09-17)
      Making class balance is essential when learning from highly skewed datasets; otherwise, a learner may classify all instances to a negative class, resulting in a high false-negative rate. As a result, a precise balancing ...

    • Bacterial colony counting could be rapid, adaptive and automated 

      Zheng, Minghua; Helian, Na; Lane, Peter; Sun, Yi; Donald, Allen (2022-12-04)
      Although many attempts have been made to automate bacterial colony counting, little has tackled the counting of clustered colonies and adaptations to handle different bacteria species. In this work, we explore the counting ...

    • Boosting Ant Colony Optimization with Reptile Search Algorithm for Churn Prediction 

      Al-Shourbaji, Ibrahim; Helian, Na; Sun, Yi; Alshathri, Samah; Abd Elaziz, Mohamed (2022-03-23)
      The telecommunications industry is greatly concerned about customer churn due to dissatisfaction with service. This industry has started investing in the development of machine learning (ML) models for churn prediction to ...

    • Burnt-in Text Recognition from Medical Imaging Modalities: Existing Machine Learning Practices 

      Osagie, Efosa; Ji, Wei; Helian, Na (2024-01-20)
      In recent times, medical imaging has become a significant component of clinical diagnosis and examinations to detect and evaluate various medical conditions. The interpretation of these medical examinations and the patient's ...

    • Complexity Reduction: Local Activity Ranking By Resource Entropy For QoS-aware Cloud Scheduling 

      Chen, Huikai; Wang, Frank Zhigang; Migliavacca, Matteo; Chua, Leon O.; Helian, Na (Institute of Electrical and Electronics Engineers (IEEE), 2016-09-01)
      The principle of local activity originated from electronic circuits, but can easily translate into other non-electrical homogeneous/heterogeneous media. Cloud resource is an example of a locally-active device, which is the ...

    • The Correlation between EEG Signals as Measured in Different Positions on Scalp Varying with Distance 

      Bhavsar, Ronakben; Sun, Yi; Helian, Na; Davey, Neil; Mayor, David; Steffert, Tony (2018-02-03)
      Biomedical signals such as electroencephalogram (EEG) are the time varying signal, and different position of electrodes give different time varying signals. There might be a correlation between these signals. It is likely ...

    • Customer Churn Prediction in Telecom Sector: A Survey and way a head 

      AlShourbaji, Ibrahim; Helian, Na; Sun, Yi; Alhameed, Mohammed (2021-01-01)
      The telecommunication (telecom)industry is a highly technological domain has rapidly developed over the previous decades as a result of the commercial success in mobile communication and the internet. Due to the strong ...

    • Delayed switching applied to memristor neural networks 

      Wang, Frank Z.; Helian, Na; Wu, Sining; Yang, Xiao; Guo, Yike; Lim, Guan; Rashid, Md Mamunur (2012)
      Magnetic flux and electric charge are linked in a memristor. We reported recently that a memristor has a peculiar effect in which the switching takes place with a time delay because a memristor possesses a certain inertia. ...

    • Dynamic and scalable storage management architecture for Grid Oriented Storage devices 

      Deng, Yuhui; Wang, Frank; Helian, Na; Wu, Sining; Liao, Chenhan (2008)
      Most of currently deployed Grid systems employ hierarchical or centralized approaches to simplify system management. However, the approaches cannot satisfy the requirements of complex Grid applications which involve hundreds ...

    • Dynamic Hierarchical Structure Optimisation for Cloud Computing Job Scheduling 

      Lane, Peter; Helian, Na; Bodla, Muhammad Haad; Zheng, Minghua; Moggridge, Paul (Springer Nature, 2022-04-15)
      The performance of cloud computing depends in part on job-scheduling algorithms, but also on the connection structure. Previous work on this structure has mostly looked at fixed and static connections. However, we argue ...

    • EED: Energy Efficient Disk drive architecture 

      Deng, Y.H.; Wang, F.; Helian, Na (2008)
      Energy efficiency has become one of the most important challenges in designing future computing systems, and the storage system is one of the largest energy consumers within them. This paper proposes an Energy Efficient ...

    • An efficient churn prediction model using gradient boosting machine and metaheuristic optimization 

      AlShourbaji, Ibrahim; Helian, Na; Sun, Yi (2023-09-02)
      Customer churn remains a critical challenge in telecommunications, necessitating effective churn prediction (CP) methodologies. This paper introduces the Enhanced Gradient Boosting Model (EGBM), which uses a Support Vector ...

    • Efficient Methods for Calculating Sample Entropy in Time Series Data Analysis 

      Bhavsar, Ronakben; Davey, Neil; Helian, Na; Sun, Yi; Steffert, Tony; Mayor, David (2018-12-11)
      Recently, different algorithms have been suggested to improve Sample Entropy (SE) performance. Although new methods for calculating SE have been proposed, so far improving the efficiency (computational time) of SE calculation ...

    • Ensemble Learning for Medical Image Character Recognition based on Enhanced Lenet-5 

      Osagie, Efosa; Ji, Wei; Helian, Na (Institute of Electrical and Electronics Engineers (IEEE), 2023-10-02)
      Generally, Medical Imaging Modalities (MIM)have a distinctive nature of low contrast, complex background, and low resolution, containing burned-in textual data of patients. The conventional OCRs hardly recognise these ...

    • Entropy4Cloud: Using Entropy-Based Complexity To Optimize Cloud Service Resource Management Computational Intelligence for Cloud Computing 

      Chen, Huikai; Wang, Frank; Helian, Na (2018-01-23)
      In cloud service resource management system, complexity limits the system’s ability to better satisfy the application’s QoS requirements, e.g. cost budget, average response time and reliability. Numerousness, diversity, ...

    • Feature weighting in DBSCAN using reverse nearest neighbours 

      Chowdhury, Stiphen; Helian, Na; Cordeiro de Amorim, Renato (2023-05-01)
      DBSCAN is arguably the most popular density-based clustering algorithm, and it is capable of recovering non-spherical clusters. One of its main weaknesses is that it treats all features equally. In this paper, we propose ...

    • Fractional memristor 

      Wang, Frank Zhigang; Shi, Luping; Wu, Huaqiang; Helian, Na; Chua, Leon O (2017-12-11)
      Based on the differential conformal transformation in the fractional order, we defined the fractional memristor in contrast to the traditional (integer-order) memristor. As an example, a typical spin-transfer torque (STT) ...

    • Grid-optimized web 3D applications on wide area network 

      Wang, Frank; Helian, Na; Meng, Lingkui; Wu, Sining; Zhang, Wen; Guo, Yike; Parker, Michael Andrew (SPIE, 2008)
      Geographical information system has come into the Web Service times now. In this paper, Web3D applications have been developed based on our developed Gridjet platform, which provides a more effective solution for massive ...

    • Improving the MXFT Scheduling Algorithm for a Cloud Computing Context 

      Moggridge, Paul; Helian, Na; Sun, Yi; Lilley, Mariana; Veneziano, Vito; Eaves, Martin (2019-08-09)
      In this paper, the Max-Min Fast Track (MXFT) scheduling algorithm is improved and compared against a selection of popular algorithms. The improved versions of MXFT are called Min-Min Max-Min Fast Track (MMMXFT) and Clustering ...

    • Instance Weighted Clustering: Local Outlier Factor and K-Means 

      Moggridge, Paul; Helian, Na; Sun, Yi; Lilley, Mariana; Veneziano, Vito (Springer Nature, 2020-05-28)
      Clustering is an established unsupervised learning method. Substantial research has been carried out in the area of feature weighting, as well instance selection for clustering. Some work has paid attention to instance ...