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The purpose of this paper is to gain a better understanding on how metasurfaces behave, in terms of currents in each unit cell. A better knowledge of their behavior could lead to an ad-hoc design for specific applications.

The methodology used is both theoretical and numerical; it is based on circuit theory and on an optimization procedure.

The results show that when the knowledge of the current in each unit cell of a metasurface is needed, the most common approximations currently used are often not accurate. Furthermore, a procedure for the termination of a metasurface, with application-driven goals, is given.

This paper investigates the distribution of the currents in a 2D metamaterial realized with magnetically coupled resonant coils. Different models for the analysis of these structures are illustrated, and the effects of the approximations they introduce on the current values are shown and discussed. Furthermore, proper terminations of the resonators on the boundaries have been investigated by implementing a numerical optimization procedure with the purpose of achieving a uniform distribution of the resonator currents. The results show that the behavior of a metasurface (in terms of currents in each single resonator) depends on different properties; as a consequence, their design is not a trivial task and is dependent on the specific applications they are designed for. A design strategy, with lumped impedance termination, is here proposed.

The purpose of this paper is to explore the optimum average current density and pulse width for electrodeposition of gold in citrate electrolyte, and it is verified that the uniformity of film thickness can be effectively improved by periodic pulse reverse electroplating.

Apply forward pulse current, forward group pulse current and periodic pulse reverse current to the electrolyte and compare the film quality. High-frequency group pulses are used in both forward and reverse directions of the periodic pulse reverse current.

It is verified by experiments that periodic pulse reverse plating is superior to forward pulse plating and forward group pulse plating in terms of particle size, compactness, impurity content and thickness uniformity of the film. Add low-frequency vibration to the cathode under the same pulse electrical parameters as a comparative experiment to prove the beneficial effect of vibration on the allowable limiting current density and plating rate.

Gold film is often used as the sealing layer of precision parts. Increasing the thickness uniformity and improving the compactness of gold film will help to reduce the size error, improve the subsequent assembly accuracy and increase the service life of wear-resistant layer. Citrate gold plating electrolyte combines the advantages of cyanide electrolyte and cyanide-free electrolyte. Hence, this research focuses on the characteristics of periodic pulse reverse plating in terms of particle size, compactness, impurity content and thickness uniformity of the film and compare it with forward pulse plating and forward group pulse plating.

The aim of this paper is to advance applied theoretical knowledge on international business (IB) ideation by designing the managing of such ideation as three recursive, multi-competence-enabled systems.

The core principles of Beer’s (1985) Viable System Model are adopted for this system design task. The Viable System Model consists of five interacting sub-systems that can support a viable IB unit.

The contribution of this design of the three recursive, multi-competence-enabled systems will be three novel pieces of the applied theoretical knowledge about recursivity and competences that advance the management of an IB unit as a whole and in particular that of IB ideation.

For future research, I initially propose that the IB ideation (unit) is being managed the more successfully within its focal contexts, the more extensively the IB ideation is designed as a set of three recursive systems enabled by respective multi-competences. Moreover, the 3-system design may serve as the frame of reference for those compatible theorization initiatives vis-à-vis viable IB ideation management that interested competence-based management scholars will conduct in the future.

I put forth the three templates (coupled with Functions 2–3) to facilitate the enhancement of the IB ideation practices among leading, innovative firms and especially by the pioneering management of IB (ideation) units.

Asynchronous current account trends between North and South of the Euro Area were accompanied by significant appreciations of real exchange rate originating in the strong shifts in consumer prices and unit labor costs in the periphery economies relative to the core countries of the Euro Area. The issue is whether the real exchange rate is a significant driver of persisting current account imbalances in the Euro Area considering that, according to some authors, differences in domestic demand are more important than is often realized. In the paper we examine relative importance of real exchange rate and demand shocks according to the current account adjustments in the Euro Area member countries. Our results indicate that while the prices and costs related determinants of external competitiveness affected current account adjustments primarily during the pre-crisis period, demand drivers shaped current account balances mainly during the crisis period.

Contemporary literature reveals that, to date, the poultry livestock sector has not received sufficient research attention. This particular industry suffers from unstructured supply chain practices, lack of awareness of the implications of the sustainability concept and failure to recycle poultry wastes. The current research thus attempts to develop an integrated supply chain model in the context of poultry industry in Bangladesh. The study considers both sustainability and supply chain issues in order to incorporate them in the poultry supply chain. By placing the forward and reverse supply chains in a single framework, existing problems can be resolved to gain economic, social and environmental benefits, which will be more sustainable than the present practices.

The theoretical underpinning of this research is ‘sustainability’ and the ‘supply chain processes’ in order to examine possible improvements in the poultry production process along with waste management. The research adopts the positivist paradigm and ‘design science’ methods with the support of system dynamics (SD) and the case study methods. Initially, a mental model is developed followed by the causal loop diagram based on in-depth interviews, focus group discussions and observation techniques. The causal model helps to understand the linkages between the associated variables for each issue. Finally, the causal loop diagram is transformed into a stock and flow (quantitative) model, which is a prerequisite for SD-based simulation modelling. A decision support system (DSS) is then developed to analyse the complex decision-making process along the supply chains.

The findings reveal that integration of the supply chain can bring economic, social and environmental sustainability along with a structured production process. It is also observed that the poultry industry can apply the model outcomes in the real-life practices with minor adjustments. This present research has both theoretical and practical implications. The proposed model’s unique characteristics in mitigating the existing problems are supported by the sustainability and supply chain theories. As for practical implications, the poultry industry in Bangladesh can follow the proposed supply chain structure (as par the research model) and test various policies via simulation prior to its application. Positive outcomes of the simulation study may provide enough confidence to implement the desired changes within the industry and their supply chain networks.

Deficits in fiscal and current account balances in a large number of countries reveal interesting implications of the causal relationship between internal and external imbalances. Empirical evidence about the occurrence of so-called twin deficits or twin surpluses provides crucial information about the validity of an intertemporal approach. However, most recent dynamic cyclical changes during the crisis period revealed many questions about the direct interconnection between macroeconomic performance and twin imbalances. In the paper we observe substantial features of twin imbalances in European transition economies. Event study (identification of large fiscal and current account changes and their parallel occurrence) and vector auto-regression methods will be employed to examine key aspects of twin imbalances. Our results suggest that current account deteriorations were predominately associated with negative public investment and savings balances (fiscal deficits), while current account improvements were predominately associated with positive private investment and savings balances, confirming empirical evidence about twin deficits in European transition economies.

The purpose of this paper is to study the effect of current-carrying condition on the electrochemical process and atmospheric corrosion behavior of the commercial aluminum alloys.

Potentiodynamic polarization tests were performed to study the electrochemical process of the aluminum alloys. Salt spray tests and weight loss tests were carried out to study the atmospheric corrosion behavior. The corrosion morphology of the alloys was observed, and the products were analyzed.

The corrosion process of four aluminum alloys was accelerated in the current-carrying condition. Moreover, the acceleration effect on A2024 and A7075 was much stronger than that on A1050 and A5052. The main factors would be the differences in microstructure and corrosion resistance between these alloys. As the carried current increased, the corrosion rate and corrosion current density of the aluminum alloys gradually increased, with the protection of the corrosion product film decreasing linearly.

This is a recent study on the corrosion behavior of conductors under current-carrying condition, which truly understands the corrosion status of power grid materials. Relevant results provide support for the corrosion protection and safe service of aluminum alloy in power systems.

Earnings management is a common term in the academic community and is likely understood by managers and professional investors, but how the large community of non-professional investors interprets this term is less clear. We examine non-professional investors’ attitudes toward earnings management and their resulting investing behaviors using a 2 × 2 mixed design. We manipulate investor role (prospective vs current) between participants and the method of earnings management within participants. We believe that different investment goals (prevention vs promotion) between current and prospective investors should lead to different investing behaviors. Consistent with our expectations, we find that current investors are more likely to maintain an equity than prospective investors are to invest in the same opportunity. Further, the consistent link between investors’ attitudes and actual investment behavior is only present for prospective investors. The prevention goal drives the current investors to maintain their investment, while the prospective investors remain more objective and focus on a goal of promotion. Importantly, prior research examining investor attitude toward earnings management has failed to link investors’ attitudes with actual investing decisions; our study attempts to fill this void by examining attitudes toward earnings management as well as subsequent investment behavior.

This paper aims to develop a model that reflects the current transformer (CT) core materials nonlinearity. The model enables simulation and analysis of the CT excitation current that includes the inductive magnetizing current and the resistive excitation current.

A nonlinear CT model is established with the magnetizing current as the solution variable. This model presents the form of a nonlinear differential equation and can be solved discretely using the Runge–Kutta method.

By simulating variations in the excitation current for different primary currents, loads and core materials, the results demonstrate that enhancing the permeability of the B–H curve leads to a more significant improvement in the CT ratio error at low primary currents.

The proposed model has three obvious advantages over the previous models with the secondary current as the solution variable: (1) The differential equation is simpler and easier to solve. Previous models contain the time differential terms of the secondary current and excitation flux or the integral term of the flux, making the iterative solution complicated. The proposed model only contains the time differential of the magnetizing current. (2) The accuracy of the excitation current obtained by the proposed model is higher. Previous models calculate the excitation current by subtracting the secondary current from the converted primary current. Because these two currents are much greater than the excitation current, the error of calculating the small excitation current by subtracting two large numbers is greatly enlarged. (3) The proposed model can calculate the distorted waveform of the excitation current and error for any form of time-domain primary current, while previous models can only obtain the effective value.

Due to the miniaturization of electronic devices, the increased current density through solder joints leads to the occurrence of electromigration failure, thereby reducing the reliability of electronic devices. The purpose of this study is to propose a finite element-artificial neural network method for the prediction of temperature and current density of solder joints, and thus provide reference information for the reliability evaluation of solder joints.

The temperature distribution and current density distribution of the interconnect structure of electronic devices were investigated through finite element simulations. During the experimental process, the actual temperature of the solder joints was measured and was used to optimize the finite element model. A large amount of simulation data was obtained to analyze the neural network by varying the height of solder joints, the diameter of solder pads and the magnitude of current loads. The constructed neural network was trained, tested and optimized using this data.

Based on the finite element simulation results, the current is more concentrated in the corners of the solder joints, generating a significant amount of Joule heating, which leads to localized temperature rise. The constructed neural network is trained, tested and optimized using the simulation results. The ANN 1, used for predicting solder joint temperature, achieves a prediction accuracy of 96.9%, while the ANN 2, used for predicting solder joint current density, achieves a prediction accuracy of 93.4%.

The proposed method can effectively improve the estimation efficiency of temperature and current density in the packaging structure. This method prevails in the field of packaging, and other factors that affect the thermal, mechanical and electrical properties of the packaging structure can be introduced into the model.