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This paper aims to address the challenges in hydroacoustic signal detection, signal distortion and target localization caused by baseline drift. The authors propose a combined algorithm that integrates short-time Fourier transform (STFT) detection, smoothness priors approach (SPA), attitude calibration and direction of arrival (DOA) estimation for micro-electro-mechanical system vector hydrophones.

Initially, STFT method screens target signals with baseline drift in low signal-to-noise ratio environments, facilitating easier subsequent processing. Next, SPA is applied to the screened target signal, effectively removing the baseline drift, and combined with filtering to improve the signal-to-noise ratio. Then, vector channel amplitudes are corrected using attitude correction with 2D compass data. Finally, the absolute target azimuth is estimated using the minimum variance distortion-free response beamformer.

Simulation and experimental results demonstrate that the SPA outperforms high-pass filtering in removing baseline drift and is comparable to the effectiveness of variational mode decomposition, with significantly shorter processing times, making it more suitable for real-time applications. The detection performance of the STFT method is superior to instantaneous correlation detection and sample entropy methods. The final DOA estimation achieves an accuracy within 2°, enabling precise target azimuth estimation.

To the best of the authors’ knowledge, this study is the first to apply SPA to baseline drift removal in hydroacoustic signals, significantly enhancing the efficiency and accuracy of signal processing. It demonstrates the method’s outstanding performance in the field of underwater signal processing. In addition, it confirms the reliability and feasibility of STFT for signal detection in the presence of baseline drift.

This chapter outlines the philosophic underpinnings of the self-management paradigm developed over the past three decades by China’s Haier Group, a global leader in white goods. The successful transformation of Haier from a small resource-poor firm to a dominant global giant is often attributed to the self-management culture established in the company by its legendary leader Zhang Ruimin. This management paradigm is a function of the humbleness displayed by Mr. Zhang Ruimin and rooted in his strong belief in the traditional Chinese philosophy of I-Ching and Daoism. We show how the hexagram of Qian (“qian”: humbleness, modesty) from I-Ching is linked to Mr. Zhang’s humble approach and analyze how the six parts of the hexagram of Qian are related to the six development stages of the Haier Group. These insights are used to give some thoughts to the leadership challenge associated with the creation of a dynamic and responsive global organization.

The purpose of this paper is to investigate the tribological properties of the WC/TiC-Co substrate under different loading conditions under three impact abrasive wear conditions.

The three body collisional wear behavior of Co alloy with WC and TiC at three impact energy was studied from 1 to 3 J. Meanwhile, the microstructure, hardness, phase transformation and wear behavior of these specimens were investigated by scanning electron microscopy, Rockwell hardness (HRV), EDS and impact wear tester. The resulting wear rate was quantified by electronic balance measurements under different pressures.

The specific wear rate increases with the increase of the nonlinearity of the impact energy and the increase in the content of WC or TiC. The effect of TiC on wear rate is greater than that of WC, but the hardness is smaller. The wear characteristics of the samples are mainly characterized by three kinds of behavior, such as cutting wear, abrasive wear and strain fatigue wear. The WC-Co with fewer TiC samples suffered heavier abrasive wear than the more TiC samples under both low and high impact energy and underwent fewer strain fatigue wears under high impact energy.

The experimental results show that the wear resistance of the Co alloy is improved effectively and the excellent impact wear performance is achieved. The results can be used in cutting tools such as coal mine cutting machines or other fields.

The purpose of this paper is to propose a deformable two-wheel-like mobile mechanism based on overconstrained mechanism, with the abilities of fast rolling and obstacle surmounting. The drive torque of the multi-mode motions is generated by self-deformation. Moreover, the analyses of feasibility and locomotivity of two mobile modes are presented.

The main body of the two-wheel-like mobile mechanism is a kind of centrally driven 4 R linkages. The mobile mechanism can achieve the capabilities of fast rolling and obstacle surmounting through integrating two mobile modes (spherical-like rolling mode and polyhedral-like obstacle-surmounting mode) and can switch to the corresponding mode to move or surmount obstacles. The mobility and kinematics of the mobile modes are analyzed.

Based on the results of kinematics analysis and dynamics analysis of the wheel-like mechanism, the spherical-like rolling mode has the capability of fast rolling, and the polyhedral-like obstacle-surmounting mode has the capability of surmounting different obstacle heights by two submodes (quasi-static obstacle-surmounting submode and dynamic obstacle-surmounting submode). The proposed concept is verified by experiments on a physical prototype.

The work presented in this paper is a novel exploration to apply bar linkages in the field of scout. The two-wheel-like mobile mechanism improves the torque imbalance of bar linkages by centrally driven method, removes the rear support structures of the traditional two-wheeled mechanisms by self-deformation and increases the height of obstacle surmounting by mode switching angle.

The purpose of this study to shed light on the importance of social media hosted content related to socially-motivated discussions. Moving from the field of communication for development, the research leverages social media as a powerful tool for collecting and analyse peer-to-peer communication towards the conceptualization of eVoices of Unheard. The deep understanding of these conversation can generate recommendations for organizations and governments designing and providing interventions fostering local socio-economic development.

The study presents a large-scale analysis of social media interactions on the topic “#favela” to generate insights into a social network structure, narrative contents and meaning generated.

Structurally, the analysed networks are comparable with those presented in current academic literature; automatic text analysis confirmed the promise of the inner value of communication for development opening the floor to conceptualization of the “eVoices of unheard”, which is the collective and conscious use of social media to mediate community discussions about tangible and intangible issues related to socio-economic development.

Framed within the rise of interactive communication for development this research show that social media an support the notion of voice proposed by Couldry (2010) moving from process (i.e. the recording of the voice) towards value (i.e. the possibility of giving an account of one’s life and its conditions to have an impact on human life and resources) thereby understanding intangible issues related with socio-economic development.

The aim of this paper is to provide evidence of the relationship between the governance structure of universities and the universities' knowledge transfer (KT) performance outcomes measured in terms of university spin-off firms university spin-offs (USOs).

The universities' board of directors has been analyzed under three profiles: the incidence of internal directors belonging to the STEM (Science, Technology, Engineering and Mathematics) faculties, the incidence of women directors and the incidence of external directors.

The findings provide evidence of a significant and positive association, for southern Italian state universities, of the presence of university STEM directors and the establishment of university spin-offs (USOs).

The article is original as, to the best of the authors’ knowledge, no study, except for the paper by Meoli et al. (2019), examined the governance of universities in relation to the establishment of academic spin-offs.