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The Polish economy has undergone major challenges and changes over the past few decades. The country's trade flows, in particular, have become more firmly tied to the country’s Western neighbors as they have grown in volume. This study examines Poland's trade balances in ten Standard International Trade Classification (SITC) sectors versus the United States of America, first testing for and isolating structural breaks in each time series. These breaks are then included in a set of the cointegration models to examine their macroeconomic determinants.

Linear and nonlinear and nonlinear autoregressive distributed lag models, both with and without dummies corresponding to structural breaks, are estimated.

One key finding is that incorporating these breaks reduces the significance of the real exchange rate in the model, supporting the hypothesis that this variable already incorporates important information. It also results in weaker evidence for cointegration of all variables in certain sectors.

This study looks only at one pair of countries, without any third-country effects.

An important country pair's trade relations is examined; in addition, the real exchange rate is shown to incorporate economic information that results in structural changes in the economy. The paper extends the existing literature by conducting an analysis of Poland's trade balances with the USA, which have not been studied in such a context so far. A strong point is a broad methodology that lets compare the results the authors obtained with different kinds of models, both linear and nonlinear ones, with and without structural breaks.

Sarcasm is a linguistic expression that usually carries the opposite meaning of what is being said by words, thus making it difficult for machines to discover the actual meaning. It is mainly distinguished by the inflection with which it is spoken, with an undercurrent of irony, and is largely dependent on context, which makes it a difficult task for computational analysis. Moreover, sarcasm expresses negative sentiments using positive words, allowing it to easily confuse sentiment analysis models. This paper aims to demonstrate the task of sarcasm detection using the approach of machine and deep learning.

For the purpose of sarcasm detection, machine and deep learning models were used on a data set consisting of 1.3 million social media comments, including both sarcastic and non-sarcastic comments. The data set was pre-processed using natural language processing methods, and additional features were extracted and analysed. Several machine learning models, including logistic regression, ridge regression, linear support vector and support vector machines, along with two deep learning models based on bidirectional long short-term memory and one bidirectional encoder representations from transformers (BERT)-based model, were implemented, evaluated and compared.

The performance of machine and deep learning models was compared in the task of sarcasm detection, and possible ways of improvement were discussed. Deep learning models showed more promise, performance-wise, for this type of task. Specifically, a state-of-the-art model in natural language processing, namely, BERT-based model, outperformed other machine and deep learning models.

This study compared the performance of the various machine and deep learning models in the task of sarcasm detection using the data set of 1.3 million comments from social media.

In this study, the authors propose a novel digital twinning approach specifically designed for controlling transient thermal systems. The purpose of this study is to harness the combined power of deep learning (DL) and physics-based methods (PBM) to create an active virtual replica of the physical system.

To achieve this goal, we introduce a deep neural network (DNN) as the digital twin and a Finite Element (FE) model as the physical system. This integrated approach is used to address the challenges of controlling an unsteady heat transfer problem with an integrated feedback loop.

The results of our study demonstrate the effectiveness of the proposed digital twinning approach in regulating the maximum temperature within the system under varying and unsteady heat flux conditions. The DNN, trained on stationary data, plays a crucial role in determining the heat transfer coefficients necessary to maintain temperatures below a defined threshold value, such as the material’s melting point. The system is successfully controlled in 1D, 2D and 3D case studies. However, careful evaluations should be conducted if such a training approach, based on steady-state data, is applied to completely different transient heat transfer problems.

The present work represents one of the first examples of a comprehensive digital twinning approach to transient thermal systems, driven by data. One of the noteworthy features of this approach is its robustness. Adopting a training based on dimensionless data, the approach can seamlessly accommodate changes in thermal capacity and thermal conductivity without the need for retraining.

Performing accurate numerical simulations of electrical drives, the precise knowledge of the local magnetic material properties is of utmost importance. Due to the various manufacturing steps, e.g. heat treatment or cutting techniques, the magnetic material properties can strongly vary locally, and the assumption of homogenized global material parameters is no longer feasible. This paper aims to present the general methodology and two different solution strategies for determining the local magnetic material properties using reference and simulation data.

The general methodology combines methods based on measurement, numerical simulation and solving an inverse problem. Therefore, a sensor-actuator system is used to characterize electrical steel sheets locally. Based on the measurement data and results from the finite element simulation, the inverse problem is solved with two different solution strategies. The first one is a quasi Newton method (QNM) using Broyden's update formula to approximate the Jacobian and the second is an adjoint method. For comparison of both methods regarding convergence and efficiency, an artificial example with a linear material model is considered.

The QNM and the adjoint method show similar convergence behavior for two different cutting-edge effects. Furthermore, considering a priori information improved the convergence rate. However, no impact on the stability and the remaining error is observed.

The presented methodology enables a fast and simple determination of the local magnetic material properties of electrical steel sheets without the need for a large number of samples or special preparation procedures.

This paper aims to design an active shock absorber scheme for use in conjunction with a passive shock absorber to suppress the horizontal vibration of elevator cars in a smaller range and shorter time. The developed active shock absorber will also improve the safety and comfort of passengers driving in ultra-high-speed elevators.

A six-degree of freedom dynamic model is established according to the position and condition of the car. Then the active shock absorber and disturbance compensation-based adaptive control scheme are designed and simulated in MATLAB/Simulink. The results are analysed and compared with the traditional shock absorber.

The results show that, compared with traditional spring-based passive damping systems, the designed active shock absorber can reduce vibration displacement by 60%, peak acceleration by 50% and oscillation time by 2/3 and is more robust to different spring stiffness, damping coefficient and load.

The developed active shock absorber and its control algorithm can significantly reduce vibration amplitude and converged time. It can also adjust the damping strength according to the actual load of the elevator car, which is more suitable for high-speed elevators.

Computer-Assisted Learning in Pediatrics Program (CLIPP) and National Board of Medical Examiners Pediatric Subject Examination (NBMEPSE) are used to assess students’ performance during pediatric clerkship. International Foundations of Medicine (IFOM) assessment is organized by NBME and taken before graduation. This study explores the ability of CLIPP assessment to predict students’ performance in their NBMEPSE and IFOM examinations.

This cross-sectional study assessed correlation of students’ CLIPP, NBMEPSE and IFOM scores. Students’ perceptions regarding NBMEPSE and CLIPP were collected in a self-administered survey.

Out of the 381 students enrolled, scores of CLIPP, NBME and IFOM examinations did not show any significant difference between genders. Correlation between CLIPP and NBMEPSE scores was positive in both junior (r = 0.72) and senior (r = 0.46) clerkships, with a statistically significant relationship between them in a univariate model. Similarly, there was a statistically significant relationship between CLIPP and IFOM scores. In an adjusted multiple linear regression model that included gender, CLIPP scores were significantly associated with NBME and IFOM scores. Male gender was a significant predictor in this model. Results of survey reflected students’ satisfaction with both NBMEPSE and CLIPP examinations.

Although students did not perceive a positive relationship between their performances in CLIPP and NBMEPSE examinations, this study demonstrates predictive value of formative CLIPP examination scores for their future performance in both summative NBMEPSE and IFOM. Therefore, students with poor performance in CLIPP are likely to benefit from feedback and remediation in preparation for summative assessments.

The study aims to understand how cultural route heritage is conceptualized and managed in China by systematically reviewing the research literature on Chinese cultural route heritage (CRH). The study intends to inspire further discussion on the theoretical and practical development of cultural routes since the development is still at a liminal stage in China.

A total of 253 research articles related to Chinese cultural rote heritage from major Chinese and English research databases China National Knowledge Infrastructure (CNKI), Web of Science (WOS) and Scopus have been comprehensively identified and reviewed for the purpose of the study.

Four major themes of research on Chinese CRH have been identified: conceptual evaluation, list of the routes and characteristics of the routes, conservation and utilization. The results revealed that China has very rich resources in CRH, many of which were formed a long time ago, which exist across vast geographic regions and have assumed multiple functions and undergone dynamic reciprocal exchanges among diverse cultures and ethnicities.

The paper summarizes some major obstacles faced by CRH in China and proposes a strategic model to address the need for a more sustainable development of CRH in the Chinese context.

The paper offers a comprehensive overview of CRH in China and discusses practical issues in management and development of heritage great in size, number and complexity.

This paper aims to present a comprehensive theoretical framework that seeks to explore the impact of cultural, legal and social factors within the external environment on the relationship between women on corporate boards and firm performance. By investigating these boundary conditions, the paper aims to shed light on how these pressures influence the aforementioned relationship.

To build the sample of companies, the authors selected companies listed on the stock exchanges of countries that represent a diverse range of institutional contexts. These contexts encompass countries with individualistic cultures, collectivist cultures, environments with mandatory gender quotas, environments without gender quotas, contexts with substantial progress toward gender equality and contexts with limited progress in achieving gender equality. To test the hypotheses, the authors used linear regression analysis as a primary analytical approach. Furthermore, they used the propensity score matching technique to address potential issues of reverse causality and unobserved heterogeneity.

The findings indicate that the positive influence of a critical mass of women on corporate boards on firm performance is contingent upon the institutional context. Specifically, the authors observed that this relationship is strengthened in institutional contexts characterized by an individualistic culture, whereas it is not as pronounced in collectivist cultural contexts. Furthermore, this research provides compelling evidence that the presence of a critical mass of women on boards leads to enhanced firm performance in institutional settings where gender quotas are not binding, as opposed to settings where such quotas are enforced. Lastly, the results demonstrate that the presence of a critical mass of women on boards is associated with improved firm performance in institutional settings characterized by low progress in achieving gender equality. However, the authors did not observe the same effect in institutional contexts that have made significant strides toward gender equality.

This research offers a unique perspective by investigating the relationship between women’s presence on corporate boards and firm performance across different institutional contexts. In this investigation, the authors recognize that gender diversity on corporate boards is not a one-size-fits-all solution and that its effects can be shaped by the unique institutional contexts in which companies operate.

Municipalities have the potential to become models of the circular economy (CE). This paper aims to examine the impact of the municipal council’s characteristics on municipal CE disclosure and promotion.

This paper is based on the resource dependence and upper echelons theories. For a sample of the 100 largest cities in Canada, a mixed methodology is used to code and analyze data and test the hypotheses.

Municipal councillors’ education and experience related to the environment or sustainability are both likely to affect CE disclosure, and their sector membership (public or private) moderates the relationship between CE disclosure and councillors’ experience. This experience may be reinforced by membership in the private sector, which has applied CE principles more extensively than the public sector has. Municipal councils with a greater number of councillors from the private sector appear to perform better in matters of transparency and to disclose more CE information on their public websites.

Municipalities could use the findings to foster their transition to CE by implementing a CE-related training plan for their councillors. A CE-dedicated section on their websites could improve transparency and inform and educate residents about CE.

The public sector could learn from the private sector’s best practices regarding CE.

This paper contributes to the literature by providing empirical evidence of the transparency and engagement of municipalities toward CE. The authors extend the resource dependence and upper echelons theories to a new context, that of public organizations.

This article aims to investigate how institutional characteristics affect the level of financial development of economies collectively and compare between developed and undeveloped economies.

A dynamic panel with 131 countries, including developed and developing ones, was utilized; the estimators of the generalized method of moments system (GMM system) model were selected because they have econometric characteristics more suitable for analysis, providing superior statistical precision compared to traditional linear estimation methods.

The results from the full panel suggest that concrete and well-defined institutions are important for financial development, confirming previous research, with a more limited scope than the present work.

Limitations of this research include the availability of data for all countries worldwide, which would make the research broader and more complete.

A panel of countries was used, divided into developed and developing countries, to analyze the impact of institutional variables on the financial development of these countries, which is one of the differentiators of this work. Another differentiator of this research is the presentation of estimates in six different configurations, with emphasis on the GMM system model in one and two steps, allowing for comparison between results.