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Bulk shipping mostly facilitates the smooth flow of raw materials around the globe. Regardless, forecasting a bulk shipbuilding orderbook is a seldom researched domain in the academic arena. This study aims to pioneer an econophysics approach coupled with an autoregressive data analysis technique for bulk shipbuilding order forecasting.

By offering an innovative forecasting method, this study provides a comprehensive but straightforward econophysics approach to forecast new shipbuilding order of bulk carrier. The model has been evaluated through autoregressive integrated moving average analysis, and the outcome indicates a relatively stable good fit.

The outcomes of the econophysics model indicate a relatively stable good fit. Although relevant maritime data and its quality need to be improved, the flexibility in refining the predictive variables ensure the robustness of this econophysics-based forecasting model.

By offering an innovative forecasting method, this study provides a comprehensive but straightforward econophysics approach to forecast new shipbuilding order of bulk carrier. The research result helps shipping investors make decision in a capital-intensive and uncertainty-prone environment.

Presents the scientific methodology from the enlarged cybernetical perspective that recognizes the anisotropy of time, the probabilistic character of natural laws, and the entry that the incomplete determinism in Nature opens to the occurrence of innovation, growth, organization, teleology communication, control, contest and freedom. The new tier to the methodological edifice that cybernetics provides stands on the earlier tiers, which go back to the Ionians (c. 500 BC). However, the new insights reveal flaws in the earlier tiers, and their removal strengthens the entire edifice. The new concepts of teleological activity and contest allow the clear demarcation of the military sciences as those whose subject matter is teleological activity involving contest. The paramount question “what ought to be done”, outside the empirical realm, is embraced by the scientific methodology. It also embraces the cognitive sciences that ask how the human mind is able to discover, and how the sequence of discoveries might converge to a true description of reality.

There are two conflicting views about electromagnetic phenomena. The first is based on the action between stationary and moving particles of electric charge and the second on energy distributions in electric and magnetic fields. The difference between these approaches is seen most clearly in the roles assigned to the potentials. According to the particle view the potentials convey the force from one particle to another, whereas in the field approach the potentials are system parameters related to the field energy. The article compares the two views and concludes that the particle view faces impossible difficulties because it ascribes local significance to quantities which are unobservable and conflicts with the quantum‐mechanical understanding of charge as a statistical distribution.

Considers the questions asked by F. Engels (1888): “Which is primary, spirit or nature?” and by Max Delbruch (1986): “How can we construct a theory of a universe without life, and therefore without mind, and then expect life and mind to evolve, somehow, from this lifeless and mindless beginning?” Views these questions historically and interprets them with further questions and analysis. Discusses the Logos doctrine and the development of scientific methodology. Asks a further question: “Can mindless objects obey mathematical laws?”. Examines the limitations of Leibniz as a scientist and the importance of his monadology. Finally, discusses Haldane’s views on the mind of a material system. Includes an extensive appendix which elaborates on the “curious vocabulary” used by the pioneers who founded wave mechanics.

Collaborative recommender systems play a crucial role in providing personalized services to online consumers. Most online shopping sites and many other applications now use the collaborative recommender systems. The measurement of the similarity plays a fundamental role in collaborative recommender systems. Some of the most well-known similarity measures are: Pearson’s correlation coefficient, cosine similarity and mean squared differences. However, due to data sparsity, accuracy of the above similarity measures decreases, which makes the formation of inaccurate neighborhood, thereby resulting in poor recommendations. The purpose of this paper is to propose a novel similarity measure based on potential field.

The proposed approach constructs a dense matrix: user-user potential matrix, and uses this matrix to compute potential similarities between users. Then the potential similarities are modified based on users’ preliminary neighborhoods, and k users with the highest modified similarity values are selected as the active user’s nearest neighbors. Compared to the rating matrix, the potential matrix is much denser. Thus, the sparsity problem can be efficiently alleviated. The similarity modification scheme considers the number of common neighbors of two users, which can further improve the accuracy of similarity computation.

Experimental results show that the proposed approach is superior to the traditional similarity measures.

The research highlights of this paper are as follows: the authors construct a dense matrix: user-user potential matrix, and use this matrix to compute potential similarities between users; the potential similarities are modified based on users’ preliminary neighborhoods, and k users with the highest modified similarity values are selected as the active user’s nearest neighbors; and the proposed approach performs better than the traditional similarity measures. The manuscript will be of particular interests to the scientists interested in recommender systems research as well as to readers interested in solution of related complex practical engineering problems.

In this paper new forms of computer simulation of non‐linear phenomena in Newtonian mechanics are developed. Energy conservation of the discrete formulations is established and applications are made to the studies of non‐linear oscillation, planetary orbits, non‐degenerate three‐body problems, and non‐linear string vibrations.

Given the nature of corona chaos, tech startups confront strategic disorientation; therefore, this study aims to constructively engage with the theory development process in the area of management decision, adopt causal complexity with a configurational approach of McKinsey's 5R paradigm and the Newtonian gravitational field.

This study provides a novel conceptualization of systematic research of explanatory mechanisms for navigating the turbulence and consequences of the COVID-19 crisis. This configurational study shows how European tech startups adopt strategies in addressing COVID-19 challenges successfully.

The analysis reveals configurations that lead to the outcome of the conceptual model, namely, reimagining the equifinal paths to the next normal. The findings suggest that, in navigating the crisis, tech startups are able to seize market opportunities, capture technological opportunities and consolidate their future positions.

The principal limitation consists of limited empirical evidence regarding tech startups’ ability to navigate Covid-19 crisis and choose the appropriate path to the next normal.

This study enhances European tech startups’ capability to adopt reflexivity and openness while navigating the Covid-19 chaotic context. Furthermore, the study provides a managerial toolkit to guide strategic decisions via deepening their understanding of the new created realities.

This study provides a novel conceptualization of systematic research on explanatory mechanisms for navigating the turbulence and consequences of the COVID-19 crisis context. This configurational study shows how European tech startups adopt strategies that address COVID-19 challenges successfully.

Our physical universe is 1.5×10¹⁰ years old. It began with the Big Bang. There is some debate about what happened in the first tenth of a second! The first 3×10⁵ years were radiation dominated. Since then it has been matter dominated. (This in accordance with the first law of thermodynamics which states that total mass-energy is conserved.) The universe has continuously expanded in space and in the future either this may continue, or expansion may stabilise at a fixed size or the universe may contract in the Big Crunch (depending on the spatial curvature). At a certain scale the universe is spatially isotropic and homogeneous. Its trajectory exhibits increasing entropy in accordance with the second law of thermodynamics. These statements are in accordance with certain models and empirical data: distant galaxies are receding from us at a velocity proportional to their distance; there is greater spatial uniformity at greater distances from us; there is uniform presence in space of radiation with a temperature of 2.7K; etc.

No scholar or researcher is able to provide robust evidence that counters the scant reflection on metatheory – mostly ontology and epistemology – underlying management studies in general, and industrial marketing and purchasing research in particular. This paper is a contribution to the indispensable discussion of metatheoretical alternatives in research, and most importantly, the strengths and shortcomings thereof, and respective implications on research questions, objectives, and findings.

This paper aims to investigate the feasibility of using the combination of Lorentz force and aerodynamic force as a propellantless control method for spacecraft formation.

It is assumed that each spacecraft is equipped with several large flat plates, which can rotate to produce aerodynamic force. Lorentz force can be achieved by modulating spacecraft’s electrostatic charge. An adaptive output feedback controller is designed based on a sliding mode observer to account for unknown uncertainties and the absence of relative velocity measurements. Aiming at distributing the control input, an optimal control allocation method is proposed to calculate the electrostatic charge of the Lorentz spacecraft and control commands for the atmospheric-based actuators.

Numerical examples are provided to demonstrate the effectiveness of the proposed control strategy in the presence of J₂ perturbations. Simulation results show that relative motion in a formation can be precisely controlled by the proposed propellantless control method under uncertainties and unavailability of velocity measurements.

The controllability of the system is not theoretically investigated in the current work.

The proposed control method introduced in this paper can be applied for small satellites formation in low Earth orbit.

The main contribution of the paper is the proposal of the propellantless control approach for satellite formation using the combination of Lorentz force and aerodynamic force, which can eliminate the requirement of the propulsion system.