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The existing dimensionality reduction algorithms suffer serious performance degradation under low signal-to-noise ratio (SNR) owing to the presence of noise. To address these problems, an enhanced spatial smoothing scheme is proposed that exploits the subarray time-space correlation matrices to reconstruct the data matrix to overcome this weakness. This method uses the strong correlation of signal and the weak correlation of noise in time and space domains, which improves the noise suppression ability.

In this paper, an enhanced spatial smoothing method is proposed. By using the strong correlation of signal and the weak correlation of noise, the time-space smoothed array covariance matrix based on the subarray time-space correlation matrices is constructed to improve the noise suppression ability. Compared with the existing Toeplitz matrix reconstruction and spatial smoothing methods, the proposed method improves the DOA estimation performance at low SNR.

Theoretical analysis and simulation results show that compared with the existing dimensionality reduction processing algorithms, the proposed method improves the DOA estimation performance in cases with a low SNR. Furthermore, in cases where the DOAs between the coherent sources are closely spaced and the snapshot number is low, our proposed method significantly improves the performance of the DOA estimation performance.

The proposed method improves the DOA estimation performance at low SNR. In particular, for the cases with a low SNR, the proposed method provides a better RMSE. The convergence of the proposed method is also faster than other methods for the low number of snapshots. Our analysis also confirms that in cases where the DOAs between the coherent sources are closely spaced, the proposed method achieves a much higher angular resolution than that of the other methods.

The purpose of this paper is to exploit the multiple-Toeplitz matrices reconstruction method combined with quadratic spatial smoothing processing to improve the direction-of-arrival (DOA) estimation performance of coherent signals at low signal-to-noise ratio (SNRs).

An improved multiple-Toeplitz matrices reconstruction method is proposed via quadratic spatial smoothing processing. Our proposed method takes advantage of the available information contained in the auto-covariance matrices of individual Toeplitz matrices and the cross-covariance matrices of different Toeplitz matrices, which results in a higher noise suppression ability.

Theoretical analysis and simulation results show that, compared with the existing Toeplitz matrix processing methods, the proposed method improves the DOA estimation performance in cases with a low SNR. Especially for the cases with a low SNR and small snapshot number as well as with closely spaced sources, the proposed method can achieve much better performance on estimation accuracy and resolution probability.

The study investigates the possibility of reusing pre-existing designs for the DOA estimation of the coherent signals. The proposed technique enables achieve good estimation performance at low SNRs.

The paper includes implications for the DOA problem at low SNRs in communication systems.

The proposed method proved to be useful for the DOA estimation at low SNR.

The purpose of this paper is to provide a holistic and systematic conceptualization of the impact of strategic human resource management (SHRM) on the psychological contract. Specifically, this paper aims to explore how the alignment of HR-systems and organizational communication influences the congruence and breach of the psychological contract.

The paper applies the signaling theory as a lens to develop a typology of four “ideal types” of SHRM configurations, each characterized by differences in the alignment of the HR-system and communication quality. Based on this typology, the influence of these different SHRM configurations on the congruence and breach of the psychological contract is being proposed.

The typology shows that the alignment of HR-systems and communication quality impact differently on the formation and breach of the psychological contract. It highlights that employees require both, highly aligned HR-systems and a high-quality communication to form congruent contract perceptions.

The configurational arguments embedded in the typology allow the conceptualization of the interrelationships between the alignment of HR-systems, organizational communication and the congruence and breach of the psychological contract. The propositions derived from the typology can guide research on SHRM as an antecedent of the psychological contract and shed light on the role of the psychological contract as a linking mechanism between SHRM and the employees’ reactions.

Research was conducted in order to identify behaviours that improve a system viability in a complex, chaotic and volatile world. The purpose of this paper is to explain why complex cybernetic systems must be authentic over time in order to maximise their viability in a complex, chaotic and volatile world.

In total, eight faculty staff from the Thunderbird School of Global Management were interviewed around the subject of “being a successful 21st century leader”. These interviews were analysed using Ricoeur's hermeneutic methodology which resulted in three behaviours being identified: be authentic, open and transparent; these behaviours were then deep interpreted according to Ricoeur's methodology using cybernetic principles. This is an innovative piece of research that brings together phenomenology, cybernetics and leadership studies but it is also limited by being a new approach.

Complex cybernetic systems must be authentic because authentic behaviour nurtures the system's identity and ensures that it is able to consistently generate a clear goal signal. It is also proposed that authenticity is important for coping with the “law of variety” by acting as an amplification mechanism.

The research implication is that it is possible to identify behaviours to improve the viability of all complex cybernetic systems.

The work is highly original because it provides a cybernetic explanation for why authentic behaviour is necessary. As far as the author is aware, no work has yet combined cybernetics with leadership behaviours and provided a cogent explanation for why authenticity is so important for system viability. The value of this work is that it clearly shows the value of authentic behaviour by showing how and why authentic behaviour improves system viability and how inauthentic behaviour harms system viability.

This paper aims to provide a multidisciplinary framework that allows an integrated understanding of reasons of success or failure in equity crowdfunding (ECF), a Fintech digital innovation of the traditional entrepreneurial finance, defining a future research agenda.

A systematic literature review (SLR) has been conducted on 127 documents extracted from two multidisciplinary repositories (Elsevier’s Scopus and Clarivate Analytics Web of Science) for the period between 2015 and early 2022. After a systematized series of inclusion and exclusion criteria, in line with the objectives and conceptual boundaries, a final list of 32 peer-reviewed articles written in English was analyzed by the authors through a meta-synthesis and thematic analysis to identify the key themes and dominant concepts.

Results show that the body of literature is recent and fast growing. The proposed integrative framework of existing research indicates that the outcome of an ECF campaign is related to signals conveyed by entrepreneurs in the form of hard information (firm characteristics, financial information, business characteristics and project description) and soft information (intellectual capital, human capital, social capital and social media network), catalyzed by digital media that facilitate also personal interactions between entrepreneurs and investors. Similarly, external factors (investors and campaign characteristics, with the fundamental role of ECF platform managers in building trust between entrepreneurs and investors) allow for the alleviation of information asymmetries. The present study sheds light on which signal mechanisms are decisive in improving the outcome, taking into consideration various disciplines which follow different but complementary perspectives.

Entrepreneurs should adapt to the transition toward the digital era, exploiting alternative financial instruments and learning effective signaling strategies, within a large variety of skills requested. Platform managers can obtain more focused information on selected entrepreneurial projects more efficiently.

Although it is fast-growing, the field of research is very recent, still fragmented and limited to the perspective/discipline followed. This SLR is, to the best of the authors’ knowledge, the first multidisciplinary and integrative analysis of reasons that motivates success, or failure, of an equity-based crowdfunding campaign. The digital nature of ECF encourages future research to move toward more pioneering and unconventional theories and research methods. Hence, the authors add to the existing literature by proposing future patterns of research based on an integration of highly technological skills and behavioral/psychological approaches.

Massive shifts in the recruitment landscape, the continually changing nature of work and workers, and extraordinary technological progress have combined to enable unparalleled advances in how current and prospective employees receive and process information about organizations. Once the domain of internal organizational public relations and human resources (HR) teams, most employment branding has moved beyond organizations’ control. This chapter provides a conceptual framework pertaining to third party employment branding, defined as communications, claims, or status-based classifications generated by parties outside of direct company control that shape, enhance, and differentiate organizations’ images as favorable or unfavorable employers. Specifically, the authors first theorize about the underlying mechanisms by which third party employment branding might signal prospective and current employees. Second, the authors develop a framework whereby we comprehensively review third party employment branding sources, thus identifying the different ways that third party employment branding might manifest. Third, using prototypical examples, the authors link the various signaling mechanisms to the various third party employment branding sources identified. Finally, the authors propose an ambitious future research agenda that considers not only the positive aspects of third party employment branding but also potential “dark sides.” Thus, the authors view this chapter as contributing to the broader employment branding literature, which should enhance scholarly endeavors to study it and practitioner efforts to leverage it.

The purpose of this study is to examine the impact of carbon performance on carbon disclosure among nonfinancial French-listed firms, while also considering the corporate board’s characteristics as a secondary objective.

This study uses a sample of Société des Bourses Françaises 120 Index (SBF-120) French-listed firms to investigate the effect of multiple carbon performance proxies on carbon disclosure based on random effects models for the period 2010–2021. Generalized method of moments regressions are used to encounter endogeneity problems.

Drawing on stakeholder theory, this paper finds that greater carbon performance leads to greater carbon disclosure. Given the growing societal awareness about climate-change issues, carbon-responsible firms are likely to disseminate relevant carbon-related information through disclosures to respond to the information demands of a varied stakeholder group. Coherent with signaling theory, large firms that undertake carbon-reduction initiatives tend to disclose more information about their enhanced carbon performance to equity participants to distinguish themselves and highlight their decarbonization efforts.

This study offers significant insights given that SBF-120 firms are involved in climate-change activities as a response to the growing institutional and societal pressure to perform better and disclose reliable environmental information in their sustainability reports.

The purpose of this paper is to design and construct an amplitude shift keying (ASK) modulator, which, using the digital binary modulating signal, controls a floating memristor emulator (MR) internally without the need for additional control circuits to achieve the ASK modulated wave.

A binary digital unipolar signal to be modulated is converted by a pre-processor circuit into a suitable bipolar modulating direct current (DC) signal for the control of the MR state, using current conveyors the carrier signal’s amplitude is varied with the change in the memristance of the floating MR. A high pass filter is then used to remove the DC control signal (modulating signal) leaving only the modulated carrier signal.

The results from the experiment and simulation are in agreement showed that the MR can be switched between two states and that a change in the carrier signals amplitude can be achieved by using an MR. Thus, showing that the circuit behavior is in line with the proposed theory and validating the said theory.

In this paper, the binary signal to be modulated is modified into a suitable control signal for the MR, thus the MR relies on the internal operation of the modulator circuit for the control of its memristance. An ASK modulation can then be achieved using a floating memristor without the need for additional circuits or signals to control its memristance.

The purpose of this paper is to outline an integrative, high-level, neurocomputational theory of brain function based on temporal codes, neural timing nets, and active regeneration of temporal patterns of spikes within recurrent neural circuits that provides a time-domain alternative to connectionist approaches.

This conceptual-theoretical paper draws from cybernetics, theoretical biology, neurophysiology, integrative and computational neuroscience, psychology, and consciousness studies.

The high-level functional organization of the brain involves adaptive cybernetic, goal-seeking, switching, and steering mechanisms embedded in percept-action-environment loops. The cerebral cortex is conceived as a network of reciprocally connected, re-entrant loops within which circulate neuronal signals that build up, decay, and/or actively regenerate. The basic signals themselves are temporal patterns of spikes (temporal codes), held in the spike correlation mass-statistics of both local and global neuronal ensembles. Complex temporal codes afford multidimensional vectorial representations, multiplexing of multiple signals in spike trains, broadcast strategies of neural coordination, and mutually reinforcing, autopoiesis-like dynamics. Our working hypothesis is that complex temporal codes form multidimensional vectorial representations that interact with each other such that a few basic processes and operations may account for the vast majority of both low- and high-level neural informational functions. These operational primitives include mutual amplification/inhibition of temporal pattern vectors, extraction of common signal dimensions, formation of neural assemblies that generate new temporal pattern primitive “tags” from meaningful, recurring combinations of features (perceptual symbols), active regeneration of temporal patterns, content-addressable temporal pattern memory, and long-term storage and retrieval of temporal patterns via a common synaptic and/or molecular mechanism. The result is a relatively simplified, signal-centric view of the brain that utilizes universal coding schemes and pattern-resonance processing operations. In neurophenomenal terms, waking consciousness requires regeneration and build up of temporal pattern signals in global loops, whose form determines the contents of conscious experience at any moment.

Understanding how brains work as informational engines has manifold long-reaching practical implications for design of autonomous, adaptive robotic systems. By proposing how new concepts might arise in brains, the theory bears potential implications for constructivist theories of mind, i.e. how observer-actors interacting with one another can self-organize and complexify.

The theory is highly original and heterodox in its neural coding and neurocomputational assumptions. By providing a possible alternative to standard connectionist theory of brain function, it expands the scope of thinking about how brains might work as informational systems.

Direction-of-arrival (DOA) estimation for wideband sources has attracted a growing interest in the recent decade because wideband sources are incorporated in many real-world applications such as communication systems, radar, sonar and acoustics. One way to estimate the DOAs of wideband signals is to decompose it into narrowband signals using discrete Fourier transform (DFT) and then apply well-established narrowband algorithms to each signal. Afterwards, results are averaged to yield the final DOAs. These techniques require scanning the full band of wideband sources, ultimately degrading the resolution and increasing complexity. This paper aims to propose a new DOA estimation methodology to solve these problems.

The new DOA estimation methodology is based on incoherent signal subspace method (ISSM). The proposed approach presents a criterion to select a single sub-band of the selected narrowband signals instead of scanning the whole signal spectrum. Then, the DOAs of wideband signals are estimated using the selected sub-band. Therefore, it is named as single sub-band (SSB)-ISSM.

The computational complexity of the proposed method is much lower than that of traditional DFT-based methods. The effectiveness and advantages of the proposed methodology are theoretically investigated, and computational complexity is also addressed.

To verify the theoretical analysis, computer simulations are implemented, and comparisons with other algorithms are made. The simulation results show that the proposed method achieves better performance and accurately estimates the DOAs of wideband sources.