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The purpose of this paper is to present issues related to the design of a modern lighting system based on LED technology. The developed system provides lighting with a high colour rendering index (up to 98); it also has many innovative functions, which make its implementation bring significant energy savings and increase the comfort of work.

In contrast to typical solutions, the dynamic synthesis of white light from six component colours was used in the presented project. This process is controlled by a microcontroller, and there is a colour temperature sensor in the feedback loop. The communication between smart luminaires and sensor modules is provided by means of a ZigBee wireless network.

The correctness of the proposed methodology has been proved by measurements and laboratory tests.

The process of improving the lighting system is continued and significant changes in the spectrum of used sensors are expected.

The proposed system based on mixing light from six components is an innovative solution that besides undoubted advantages entails a more elaborate electronic circuitry. However, good characteristics of the obtained light, as well as the possibility of compensating for changes in colour temperature of natural light and reducing the impact of aging of LEDs, in the authors’ opinion, make the proposed solution find its place on the market.

The proposed solution is original, both in terms of the light mixing technique and advanced functionality offered by the system.

The COVID-19 pandemic, having emerged early in the year 2020, had a devastating impact on the whole aviation industry. Airlines were particularly hit hard, given unprecedented border closures, the inability to adapt to highly volatile demand, and an embarrassing lack of overall pandemic preparedness. As of summer 2022, the airline industry seems on the track of strong recovery, with many airlines returning to profits and passenger numbers occasionally exceeding those of pre-COVID-19 levels. This study investigates the induced pandemic cycle, from January 2020 to December 2022, through tools from the network science literature. We model airline networks as a collection of nodes, representing airports, and a collection of links, representing direct flights between airports. This analysis has a strong focus on spatiotemporal evolution of airlines worldwide during the COVID-19 pandemic, leading to a comprehensive description of network science effects and counter measures during this excessive health and economic shock. Such an analysis could be helpful for better dealing with future pandemics, which are likely to emerge, if potential lessons learned are not implemented by the aviation industry.

Distribution research was an important field of research in Germany especially in the 1920s and 50s. After that, the major research interests in the area of marketing and internal trade shifted to other topics. Retailing and wholesaling institutions became more powerful and new technologies supporting physical distribution activities began to attract researchers to deal with distribution problems. Distribution as treated in this synopsis covers the areas of retailing, wholesaling, industrial selling and physical distribution.

This study aims to examine whether senior Enron executive emails celebrated, or at least left a space for, corporate irresponsibility. Engaging with prior organizational-focused research, we investigate how corporate emails sent by senior executives help constitute Enron by communicating to employees senior management’s stance about important topics and social characters.

The study analyzes the 527,356 sentences contained in 144,228 emails sent by Enron senior executives and other employees in the three-year period (1999–2001) before the company’s collapse. Sentences are used as the base-level speech unit because we are interested in identifying the tone and emotions expressed about specific topics and stakeholders. Tone is measured using Loughran and McDonald’s (2016) financial dictionary approach, and emotion is measured using Mohammad and Turney’s (2013) NRC word-emotion lexicon. Least Absolute Shrinkage and Selection Operator (LASSO) regressions are used to explore the determinants of senior management tone and emotions.

The analysis illustrates that while both senior executives and other employees utilized email to help accomplish task-related activities, they employed different evaluative tones to talk about key topics and stakeholders. Also important is what is left unsaid, with a “spiral of silence” emanating from senior management that created a space for corporate irresponsibility.

Combining advanced computerized textual analysis with qualitative techniques, we analyze a unique dataset to explore micro details involved in using email to communicate a tone at the top. The findings illustrate how what is said or not said by senior management contributes to the constitution of an organization.

The longitudinal impact of media multitasking on the development of executive function has been understudied, as most of the existing studies are cross-sectional. This longitudinal study addresses this research gap and uses multiple measures, i.e. behavioral and self-reported, to explore the impact of media multitasking on the executive function of Chinese adolescents.

This study followed 99 Chinese adolescents (M_age = 14.41, SD = 1.10; 42 boys and 57 girls) for one year using both behavioral (2-back, Stroop Color and Number-letter tasks) and self-reported (questionnaire) measures. The adolescents were categorized as either heavy/high media multitaskers (HMMs; 19 boys and 29 girls) or light/low media multitaskers (LMMs; 23 boys and 28 girls). They were tested at baseline, 6 months later and 12 months later.

The results indicated that the accuracy scores for all cognitive tasks differed with age, but the switch-cost in the shifting task and the self-reported measures of executive function did not. And there were consistent differences between the HMMs and LMMs in the self-reported measures and 2-back accuracy. However, the interaction effect was found only in shifting ability, indicating a decline in the LMMs' self-reported problematic shifting behavior in daily life.

This study used behavioral and self-reported measures to confirm the longitudinal impact of media multitasking on executive function. The impact of media multitasking on executive function is more apparent in daily-life behavior than in cognitive task performance.