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In typical model-based calibration, linearization errors are derived inevitably, and non-negligible negative impact will be induced on the identification results if the rotational kinematic errors are not small enough or the lengths of links are too long, which is common in the industrial cases. Thus, an accurate two-step kinematic calibration method minimizing the linearization errors is presented for a six-DoF serial robot to improve the calibration accuracy.

The negative impact of linearization on identification accuracy is minimized by removing the responsible linearized kinematic errors from the complete kinematic error model. Accordingly, the identification results of the dimension-reduced new model are accurate but not complete, so the complete kinematic error model, which achieves high identification accuracy of the rest of the error parameters, is combined with this new model to create a two-step calibration procedure capable of highly accurate identification of all the kinematic errors.

The proportions of linearization errors in measured pose errors are quantified and found to be non-negligible with the increase of rotational kinematic errors. Thus, negative impacts of linearization errors are analyzed quantitatively in different cases, providing the basis for allowed kinematic errors in the new model. Much more accurate results were obtained by using the new two-step calibration method, according to a comparison with the typical methods.

This new method achieves high accuracy with no compromise on completeness, is easy to operate and is consistent with the typical method because the second step with the new model is conveniently combined without changing the sensors or measurement instrument setup.

Accompany with the development of economy, the environment becomes deteriorating, especially in developing countries. Many studies found that foreign direct investment (FDI) with the effect of technology spillover would be one of the best ways to solve the environmental problem. By using the model of trade theory distinguishing between environmental and productive technology and separately analyzing the technology spillover effect of these two technologies on reducing environmental pollution in host countries, we find that the pollution problem could be worse if more intensive pollution industrial structure is induced by the environmental technology development. Naturally, this did not mean restraining the development of technology, but rather emphasizing the importance of the regulation and the industrial structure.

This study aims at establishing a linkage between IFRS adoption and environmental pollution in Africa. More so, the role of institution was emphasized as a possible ameliorator of environmental pollution in the face of IFRS adoption.

The empirical model builds on the traditional EKC hypothesis, by including IFRS adoption variable and an interaction term (which captures the multiplicative between IFRS adoption and institutions). Data was gathered for 47 African countries for the period 2001–2013. The SGMM technique was used in the estimation process.

The robust estimation reveals that a positive and significant linkage exist between IFRS adoption and environmental pollution. The interactive variable also shows that the effect of IFRS on the environment will reduce when institutions quality (in the form of bureaucratic corruption) is addressed.

The linkage between IFRS and the environment has not received empirical attention. This is partly due to the fact that accounting phenomenon is rarely linked to macroeconomic outcomes. However, there is a rising interest in the role of accounting institutions on economic outcomes and this study contributes sufficiently to this budding body of knowledge.

The purpose of this paper is to construct a proportion-integral-type (PI-type) memristor, which is different from that of the previous memristor emulator, but the constructing memristive chaotic circuit possesses line equilibrium, leading to the emergence of the initial conditions-related dynamical behaviors.

This paper presents a PI-type memristor emulator-based canonical Chua’s chaotic circuit. With the established mathematical model, the stability region for the line equilibrium is derived, which mainly consists of stable and unstable regions, leading to the emergence of bi-stability because of the appearance of a memristor. Initial conditions-related dynamical behaviors are investigated by some numerically simulated methods, such as phase plane orbit, bifurcation diagram, Lyapunov exponent spectrum, basin of the attraction and 0-1 test. Additionally, PSIM circuit simulations are executed and the seized results validate complex dynamical behaviors in the proposed memristive circuit.

The system exhibits the bi-stability phenomenon and demonstrates complex initial conditions-related bifurcation behaviors with the variation of system parameters, which leads to the occurrence of the hyperchaos, chaos, quasi-periodic and period behaviors in the proposed circuit.

These memristor emulators are simple and easy to physically fabricate, which have been increasingly used for experimentally demonstrating some interesting and striking dynamical behaviors in the memristor-based circuits and systems.

This paper aims to classify the inductorless Chua’s circuits into two types from the topological structures and construct a chaotic circuit under this new classification framework.

In this paper, two types of inductorless Chua’s circuit models are presented from topological structure, among which the first type of inductorless Chua’s circuit (FTICC) model is much closer to the original Chua’s circuit. Under this classification framework, a new inductorless Chua’s circuit that belongs to the FTICC model is built by replacing LC parallel resonance of the original Chua’s circuit with a second order Sallen–Key band pass filter.

Compared with a paradigm of a reported inductorless Chua’s circuit that belongs to the second type of inductorless Chua’s circuit (STICC) model, the newly proposed circuit can present the attractors which are much more closely to the original Chua’s attractors. The dynamical behaviors of coexisting period-doubling bifurcation patterns and boundary crisis are discovered in the newly proposed circuit from both numerical simulations and experimental measurements. Moreover, a crisis scenario is observed that unmixed pairs of symmetric coexisting limit cycles with period-3 traverse through the entire parameter interval between coexisting single-scroll chaotic attractors and double-scroll chaotic attractor.

The newly constructed circuit enriches the family of inductorless Chua’s circuits, and its simple topology with small printed circuit board size facilitates the various types of engineering applications based on chaos.

Luxury and communism are perceived to be ideologically incompatible values. Prior to the end of the Cold War, luxury tourism and socialist economies had an accommodating relationship and were rationalised at the national level for foreign exchange revenues, showcasing national development in some instances and finally promoting leisure and political education. However, contemporary scholarship on political ideology and luxury tourism is limited given changes in the political and tourism domain over the last two decades. The start of luxury travel and increasing private promotion in Vietnam comes at a time where the communist regime is hurriedly developing the economy at a breakneck speed. Key cities like Hanoi and Ho Chi Minh City have become the forefront of luxury travel for Vietnam. Luxury malls, fine dining and five-star hotel resorts have sprung over the years in tandem with Doi Moi (economic restructuring). Tourism literature has seldom ventured into regime politics and luxury tourism. Using a historical approach, the chapter traces the preamble of luxury tourism in the age of Vietnam's modernity. A critical assessment of contemporary luxury tourism in Vietnam reveals a favourable relationship with socialist principles.

This study investigates the impact of universities' social marketing initiatives on students’ development of personal (altruistic, biospheric and egoistic) and social values, leading to their pro-environmental behaviors.

This study applies quantitative deductive research. This study examined the value-belief-norms (VBN) theory, adding social values to the framework. This study took place in Egypt from January 2023 to March 2023. The population of focus was college students (whether at public or private universities). Students were requested to fill out the questionnaire by scanning a quick-response (QR) code, which linked to a Google Form. After data collection, 410 questionnaires were analyzed using statistical package for social science.

This study developed empirical evidence that clarifies that social marketing initiatives done by universities have the power to develop students’ personal and social values. Values trigger behavior change. Social values lead to students’ pro-environmental behaviors; personal egoistic values lead to students’ pro-environmental behaviors; personal biospheric values lead to students’ pro-environmental behaviors and personal altruistic values does not lead to students’ pro-environmental behaviors.

This study offers firsthand insight in understanding how social marketing is an effective tool to develop students’ values that are needed to inspire the right behaviors to preserve and protect the environment. This study builds upon the VBN theory, explaining the significant underlying environmental values that should be developed through universities’ non-academic initiatives (such as marketing activities) to inform behaviors needed to better the community, such as pro-environmental behaviors.

The ammeter can measure the direct current and low-frequency alternating current through the wires, but it is difficult to measure complex waveforms. The oscilloscope can measure complex waveforms, but it is easy to measure the voltage waveform and difficult to measure the current waveform. Thus, how to measure complex current waveforms with oscilloscope is an important and crucial issue that needs to be solved in practical engineering applications. To solve the above problems, an active short circuit line method is proposed to measure the volt-ampere characteristic curve of chaotic circuits.

In this paper, an active short circuit line method is proposed to measure the volt-ampere characteristic curve of various chaotic circuits especially for memristive systems. A memristor-based chaotic system is introduced, and the corresponding memristor-based circuit is constructed and implemented by using electronic components.

The chaotic attractors and volt-ampere characteristic curve of the memristor-based chaotic circuit are successfully analyzed and verified by oscilloscope measurement with the proposed active short circuit line method. Accordingly, the hardware circuit experiments are carried out to validate the effectiveness and feasibility of the active short circuit line method for these chaotic circuits. A good agreement is shown between the numerical simulations and the experimental results.

The primary contributions of this paper are as follows: an active short circuit line method for measuring the volt-ampere characteristic curve of chaotic circuits is proposed for the first time. A memristor-based chaotic system is also constructed by using memristor as nonlinear term. Then, the active short circuit line method is applied to measure the volt-ampere characteristic curve of the corresponding memristor-based chaotic circuit.

This study aims to examine how higher education can mold pro-environmental actions among students with educational social-marketing leads; it probes into the direct influence of four value orientations toward pro-environmental beliefs, norms and behaviors.

This quantitative research sought deductive reasoning. Data gathering took place in January 2023, following a cross-sectional framework. The researcher visited various private universities in Egypt, which used effort to change the practices among students toward sustainable developments, distributing digitally administrated questionnaires to students on campus. Through convenience nonprobability sampling, 581 questionnaires were collected and statistically analyzed, using SPSS.

This study shows that altruistic and biospheric value impact students’ personal beliefs toward pro-environmental behaviors; students’ personal beliefs significantly impact the norms that are present on campus; the norms found on campus impact significantly students to behave as green passengers, recyclers and utility-savers.

Higher education institutions play a significant role in promoting the manifestations of rationality and objectivity among students about environmental challenges and sustainable development. Eco-friendly behaviors are rooted in values; thus, understanding the initial values among students is critical in developing coping strategies and social marketing initiatives that inspire the needed conservational behaviors.

By aligning the value-belief-norm theory with two disciplines (higher education on sustainability and social marketing), this study builds upon the theory, identifying the underlying value-structures that inspire students’ necessary environmental and sustainable behaviors to improve societies for future generation rightness. This study provides more nuanced insights into a better educational intervention for shaping students’ manners toward environmentalism to improve communities worldwide.

The purpose of this study is to examine how the childhood trauma experiences of CEOs influence firms’ internationalization.

The research used a difference-in-difference method with constructing a treatment group whose chief executive officer (CEO) experienced the great famine in China between the ages of 7 and 11, and a control group whose CEO was born within three years after 1961.

The study reveals a significant inverse correlation between CEOs’ childhood trauma experiences and firm internationalization. However, this correlation is weaker in the case of state-owned enterprises and firms led by CEOs with overseas work experience.

To the best of the authors’ knowledge, this study is the first to extend the theoretical framework to elucidate firms’ internationalization by introducing childhood trauma theory into the field of international business literature. Second, the authors link the literature on the effect of CEO explicit traits and psychological traits on firm internationalization by exploring how CEOs’ childhood trauma experience shapes their risk aversion, which, in turn, influences firm internationalization. Third, the authors address the call for examining the interplay of CEO life experiences by scrutinizing the moderating effect of CEO overseas work experience on the association between CEOs’ childhood trauma exposure and firm internationalization.