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Article
Publication date: 20 June 2022

Lokesh Singh, Rekh Ram Janghel and Satya Prakash Sahu

Automated skin lesion analysis plays a vital role in early detection. Having relatively small-sized imbalanced skin lesion datasets impedes learning and dominates research in…

Abstract

Purpose

Automated skin lesion analysis plays a vital role in early detection. Having relatively small-sized imbalanced skin lesion datasets impedes learning and dominates research in automated skin lesion analysis. The unavailability of adequate data poses difficulty in developing classification methods due to the skewed class distribution.

Design/methodology/approach

Boosting-based transfer learning (TL) paradigms like Transfer AdaBoost algorithm can compensate for such a lack of samples by taking advantage of auxiliary data. However, in such methods, beneficial source instances representing the target have a fast and stochastic weight convergence, which results in “weight-drift” that negates transfer. In this paper, a framework is designed utilizing the “Rare-Transfer” (RT), a boosting-based TL algorithm, that prevents “weight-drift” and simultaneously addresses absolute-rarity in skin lesion datasets. RT prevents the weights of source samples from quick convergence. It addresses absolute-rarity using an instance transfer approach incorporating the best-fit set of auxiliary examples, which improves balanced error minimization. It compensates for class unbalance and scarcity of training samples in absolute-rarity simultaneously for inducing balanced error optimization.

Findings

Promising results are obtained utilizing the RT compared with state-of-the-art techniques on absolute-rare skin lesion datasets with an accuracy of 92.5%. Wilcoxon signed-rank test examines significant differences amid the proposed RT algorithm and conventional algorithms used in the experiment.

Originality/value

Experimentation is performed on absolute-rare four skin lesion datasets, and the effectiveness of RT is assessed based on accuracy, sensitivity, specificity and area under curve. The performance is compared with an existing ensemble and boosting-based TL methods.

Details

Data Technologies and Applications, vol. 57 no. 1
Type: Research Article
ISSN: 2514-9288

Keywords

Article
Publication date: 18 April 2016

Deepak B B V L and Pritpal Singh

In the previous decade, unmanned aerial vehicles (UAVs) have turned into a subject of enthusiasm for some exploration associations. UAVs are discovering applications in different…

1891

Abstract

Purpose

In the previous decade, unmanned aerial vehicles (UAVs) have turned into a subject of enthusiasm for some exploration associations. UAVs are discovering applications in different regions going from military applications to activity reconnaissance. The purpose of this paper is to overview a particular sort of UAV called quadrotor or quadcopter.

Design/methodology/approach

This paper includes the dynamic models of a quadrotor and the distinctive model-reliant and model-autonomous control systems and their correlation.

Findings

In the present time, focus has moved to outlining autonomous quadrotors. Ultimately, the paper examines the potential applications of quadrotors and their part in multi-operators frameworks.

Originality/value

This investigation deals with the review on various quadrotors, their applications and motion control strategies.

Details

International Journal of Intelligent Unmanned Systems, vol. 4 no. 2
Type: Research Article
ISSN: 2049-6427

Keywords

Open Access
Article
Publication date: 18 June 2019

Tolga Umut Kuzubas, Burak Saltoğlu, Ayberk Sert and Ayhan Yüksel

The purpose of this paper is to provide an in-depth performance evaluation of funds offered by the Turkish pension system.

1906

Abstract

Purpose

The purpose of this paper is to provide an in-depth performance evaluation of funds offered by the Turkish pension system.

Design/methodology/approach

This paper compares aggregate fund index returns with the corresponding asset class returns, estimates a factor model to decompose excess returns to factor exposures, i.e., β return and excess return originating from residual α and analyzes persistence of fund returns using migration tables and Fama–MacBeth regressions and tests for market timing ability.

Findings

Majority of pension funds are unable to generate excess returns. Majority of funds are unable to generate a positive α and fund returns are predominantly driven factor exposures. There is evidence for slight persistence in returns, mainly due to factor exposures and funds do not exhibit market timing ability.

Originality/value

In this paper, the authors perform an in-depth analysis of pension fund performance for the Turkish pension fund system. The authors identify weaknesses and strengths of the pension fund industry and provide policy recommendations for a better design of pension fund system.

Details

Journal of Capital Markets Studies, vol. 3 no. 1
Type: Research Article
ISSN: 2514-4774

Keywords

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