Search Results (883)

Freemium, a popular business model in the digital economy, offers a basic product for free while charging for advanced features or value-added services. This pricing strategy enables platforms to attract a broad user base and then monetize through premium offerings. Customer characteristics and service price are important factors affecting customer choice behavior in such a model. Based on consumption stickiness, we consider a monopoly that provides value-added services by incorporating a multinomial logit model into a two-stage dynamic pricing model. First, we analyze the optimal pricing of value-added services under a normal sales scenario. We then consider optimal pricing during the marketing period under two strategies—level improvement for value-added services and quality reduction for a basic product—and analyze the applicability of each. The results show that increasing the value-added service level has a positive effect on the optimal price of value-added services, whereas reducing the basic product quality has no effect on the optimal price. Furthermore, the numerical simulation shows that when the depth of consumer stickiness is low, the optimal marketing strategy reduces the quality of the basic product, the price of value-added services should be higher than that in the normal sales period but lower than the price under the level-improvement strategy for value-added services; otherwise, improving the level of the value-added services becomes the optimal approach. This study provides a theoretical basis and decision support for product quality design and service pricing that applies to freemium platforms. Full article

The demand for functional beverages is increasing as consumers seek options that offer health benefits, and plant-based beverages are gaining popularity for their associated advantages. The objective of this study was to optimize the formulation of a chickpea and hibiscus beverage to maximize flavor sensory acceptance, antioxidant capacity, and anthocyanin content using a mixture design and characterize the optimal formulation. An extreme vertices mixture design was employed, with fixed proportions of chickpea beverage (66.5%) and inulin (2%), while varying the proportions of hibiscus decoction, monk fruit, and cinnamon powder. Additionally, the Kano model was used to classify the beverage’s attributes. The optimized formulation consisted of 31.41% hibiscus decoction, 0.48% monk fruit, and 0.61% cinnamon powder, achieving 329.2 µmol TE/100 mL (antioxidant capacity), 3.567 mg C3GE/100 mL (anthocyanin content), and a flavor rating of 6.2. The Kano model classified good taste, functional properties, monk fruit sweetening, and chickpeas as attractive attributes, with functional properties obtaining the highest satisfaction index (0.88). These results demonstrate that employing a mixture design is an effective tool to enhance health-related aspects and consumer acceptance. Additionally, the incorporation of the Kano model provides a broader perspective on the development of functional beverages by identifying key attributes that influence product acceptance and market success. Full article

Semantic communication has attracted considerable interest due to its potential to support emerging human-centric services, such as holographic communications, extended reality (XR), and human-machine interactions. Different from traditional communication systems that focus on minimizing the symbol-level distortion (e.g., bit error rate, signal-to-noise ratio, etc.), semantic communication targets at delivering the intended meaning at the destination user which is often quantified by various statistical divergences, often referred to as the semantic distances. Currently, there still lacks a unified framework to quantify the rate-distortion tradeoff for semantic communication with different task-specific semantic distance measures. To tackle this problem, we propose the task-specific rate-distortion theory for semantic communication where different task-specific statistic divergence metrics can be considered. To investigate the impact of different semantic distance measures on the achievable rate, we consider two popular tasks, classification and signal generation. We present the closed-form expressions of the semantic rate-distortion functions for these two different tasks and compare their performance under various scenarios. Extensive experimental results are presented to verify our theoretical results. Full article

The integration of urban bus and subway services is critical for attracting passengers and for the sustainable development of public transit, as it helps to boost ridership with an extensive service that combines the attractions of buses and subways. To identify barriers in transferring from bus to subway or vice versa at different periods of the day, this research develops the popular evaluation indices found in the literature and revises them to reflect the most critical attributes of transfer quality. Thus, the deficiencies of transferring from subway to bus or vice versa are independently examined. Motivated by the changes in the indices at different periods, the day is divided into multiple periods. Then, dynamic transfer-volume-based TOPSIS is developed, instead of assigning index weights based on period sequence. The index weight is revised to emphasize the peak periods. Taking a case study in Suzhou, the barriers to inter-modal transfer are identified between subways and buses. It is found that subway-to-bus transfer quality is only one-third of that of bus-to-subway transfers due to the great changes in bus runs (19–45 vs. 14–26), lower bus coverage rates (0.42–0.47 vs. 0.50–0.55), and larger deviation of connected POIs (9.0–9.4 vs. 1.1–1.8), as well as the lower reliability of connected bus lines (0.3–0.47 beyond peaks vs. 0.58 and 0.96). Multi-faceted implementations are recommended for inter-modal subway-to-bus transfers and bus-to-subway transfers, respectively. The research provides insights on enhancing bus–subway transfer quality with finer detail into different periods, to encourage the loyalty of transit passengers with more stable and reliable bus as well as transit service. Full article

Tomatoes are one of the most popular vegetables. The high level of production in the world is often offset by numerous losses that occur during production in the field or in the post-production stages. Preservation in its fresh form is a challenge, particularly due to pest attacks on stored food. A promising natural and inexpensive solution to protect against pests is the use of chitosan (CH), which can be associated with essential oils (EOs) with repellent effects. In previous studies, some protective effects have been demonstrated using chitosan films coated with EOs. In this study, we tested CH-EOs associations on tomato fruits to evaluate their efficacy against attacks by the pest Spodoptera littoralis (Boisduval, 1833), taking into account parameters such as age and body mass of the larvae and the effect over time (10 days) of the treatments. Our study highlights the potential of the combination of CH and cinnamon EO as an environmentally friendly solution to protect tomatoes from S. littoralis attack. Here we found a repellent effect of cinnamon EO combined with CH on S. littoralis larvae, with no effect on larval attractiveness or repellence for CH alone and the four other EOs tested. The main compound in cinnamon EO, (E)-cinnamaldehyde, had no overall repellent effect on larvae, but had specific effects when larval age, body mass, and post-treatment time were taken into account. Full article

In recent times, fiber reinforced polymer composite materials have become more popular due to their remarkable features such as high specific strength, high stiffness and durability. Particularly, Carbon Fiber Reinforced Polymer (CFRP) composites are one of the most prominent materials used in the field of transportation and building engineering, replacing conventional materials due to their attractive properties as mentioned. In this work, a CFRP laminate is fabricated with carbon fiber mats and epoxy by a hand layup technique. Alumina (Al₂O₃) micro particles are used as a filler material, mixed with epoxy at different weight fractions of 0% to 4% during the fabrication of CFRP laminates. The important objective of the study is to investigate the influence of alumina micro particles on the mechanical performance of the laminates through characterization for various physical and mechanical properties. It is revealed from the results of study that the mass density of the laminates steadily increased with the quantity of alumina micro particles added and subsequently, the porosity of the laminates is reduced significantly. The SEM micrograph confirmed the constituents of the laminate and uniform distribution of Al₂O₃ micro particles with no significant agglomeration. The hardness of the CFRP laminates increased significantly for about 60% with an increase in weight % of Al₂O₃ from 0% to 4%, whereas the water gain % gradually drops from 0 to 2%, after which a substantial rise is observed for 3 to 4%. The improved interlocking due to the addition of filler material reduced the voids in the interfaces and thereby resist the absorption of water and in turn reduced the plasticity of the resin too. Tensile, flexural and inter-laminar shear strengths of the CFRP laminate were improved appreciably with the addition of alumina particles through extended grain boundary and enhanced interfacial bonding between the fibers, epoxy and alumina particles, except at 1 and 3 wt.% of Al₂O₃, which may be due to the pooling of alumina particles within the matrix. Inclusion of hard alumina particles resulted in a significant drop in impact strength due to appreciable reduction in softness of the core region of the laminates. Full article

Tourism learning resources refer to tourism attractions that carry learning content or stimulate learning behaviors for tourists, thereby determining the quality and effectiveness of tourists’ learning experiences. Actively developing tourism learning resources and manifesting tourism learning functions serves as an innovative practical path for cultivating new quality productivity in tourism and bears the contemporary mission of constructing a national lifelong learning system in the context of Chinese-style modernization. However, at the present stage, Chinese tourists, tourism enterprises, and government functional departments still lack a clear and systematic understanding of the connotations and characteristics of tourism learning resources. This knowledge gap restricts the depth and breadth of resource development. To address the identified gaps, this study begins by exploring the relationship between tourism and learning. Through a systematic literature review, it aims to develop a conceptual framework for tourism learning resources to promote lifelong learning and support sustainable tourism development. Taking this framework as a tool, this paper first explains the connotation and characteristics of tourism learning resources; secondly, classifies them into knowledge popularization, natural observation, skill experience, inspirational development, and cultural recreation types; thirdly, identifies their functional manifestations as acquiring experience, knowledge, skills, and wisdom; and finally, proposes development strategies for tourism learning resources. The most critical strategies identified are (1) enhancing tourism learning literacy, (2) optimizing learning-oriented products, and (3) constructing regionally integrated learning destinations. Full article

Coenzyme Q₁₀ (CoQ₁₀) has attracted widespread attention in recent years due to its momentous physiological functions. Microbial fermentation is the major method in CoQ₁₀ industrial production, and Rhodobacter sphaeroides is the main strain for the production of CoQ₁₀ by fermentation. Optimization of the culture medium is a popular solution to improve the metabolite production. Culture medium is the material basis for microbial growth and product synthesis, of which inorganic salts are a key ingredient. Uniform design (UD), artificial neural network (ANN), and genetic algorithm (GA) are the main research methods. Through uniform design (UD) and artificial neural network/genetic algorithm (ANN-GA) progressive optimization, an optimal formulation of the inorganic salts in fermentation medium was obtained (g·L⁻¹): MgSO₄ 12, NaCl 2.5, FeSO₄ 1.6, KH₂PO₄ 0.8, MnSO₄ 0.1, CaCl₂ 0.1. Ultimately, the fermentation yield of CoQ₁₀ could reach 255.36 mg·L⁻¹. ANN-GA exhibited a superior prediction capability compared to UD. Compared to UD, the optimization results of ANN-GA had a smaller relative error (ANN-GA 1.23%; UD 3.01%) and a higher increase rate in the fermentation level of CoQ₁₀ (ANN-GA 4.1%; UD 2.04%). R. sphaeroides had a high demand for Mg²⁺. Full article

This study investigates participation patterns in publicly accessible educational events organized by a college policy and research center. These programs, which addressed topics related to energy and sustainability, were conducted both online and in person and featured expert speakers from government, business, and nonprofit sectors. By analyzing registration data from over 1400 participants across multiple events, the study identifies key trends in attendance, including sector affiliation, repeat attendance, and the impact of regional relevance on program popularity. The findings indicate that most participants were private citizens or affiliated with the business sector, with lower attendance rates from academia, government, and nonprofit sectors. Furthermore, the study underscores the popularity of regionally pertinent topics and the challenges in attracting participants to more specialized topics. The research highlights the importance of providing low-barrier, accessible adult environmental education (AEE) opportunities. It suggests that colleges and universities, with organizational capabilities and access to expert speakers, are uniquely positioned to offer these programs. This study contributes to the limited quantitative research on AEE, addressing a gap in understanding participation patterns and engagement within the field. Full article

Current tourism route recommendation systems often overemphasize popular destinations, thereby overlooking geographical accessibility between attractions and the experiential coherence of the journey. Leveraging multidimensional attribute perceptions derived from tourist reviews, this study proposes a Spatial–Semantic Integrated Model for Tourist Attraction Representation (SSIM-TAR), which holistically encodes the composite attributes and multifaceted evaluations of attractions. Integrating these multidimensional features with inter-attraction relationships, three relational metrics are defined and fused: spatial proximity, resonance correlation, and thematic-sentiment similarity, forming a Tourist Attraction Multidimensional Association Network (MAN-SRT). This network enables precise characterization of complex inter-attraction dependencies. Building upon MAN-SRT, the Tourism Sentiment Chain (TSC) model is proposed that incorporates geographical accessibility, associative resonance, and thematic-sentiment synergy to optimize the selection and sequential arrangement of attractions in personalized route planning. Results demonstrate that SSIM-TAR effectively captures the integrated attributes and experiential quality of tourist attractions, while MAN-SRT reveals distinct multidimensional association patterns. Compared with popular platforms such as “Qunar” and “Mafengwo”, the TSC approach yields routes with enhanced spatial efficiency and thematic-sentiment coherence. This study advances tourism route modeling by jointly analyzing multidimensional experiential quality through spatial–semantic feature fusion and by achieving an integrated optimization of geographical accessibility and experiential coherence in route design. Full article

Gaming is a popular leisure activity with an increasing number of participants worldwide. It has positive aspects as well as a problematic side—Internet Gaming Disorder (IGD). This behavior attracts concern among mental health and education professionals because of possible negative psycho-emotional factors. This study aimed to assess IGD among Japanese and Israeli university students and other young adults. We explored the association of culture and IGD based on gender, burnout, and loneliness. It was hypothesized that IGD would differentiate based on the respondent country (i.e., Japan or Israel) and gender, with males reporting higher levels. Furthermore, IGD would be associated with higher levels of loneliness and burnout, regardless of country. Qualtrics and Excel platforms were used to collect responses to the Internet Gaming Disorder Scale–Short Form, De Jong Gierveld Loneliness Scale, and Short Burnout Measure (SBM). Data was gathered from a cross-cultural sample of 1318 male and female university students and other young adults in Japan and Israel, between 2022 and 2023. Japanese gamers showed less IGD (p < 0.05); and males evidenced higher levels regardless of their country (p < 0.001). IGD was significantly associated with loneliness (p < 0.001) and burnout (p < 0.001). However, multiple regression analysis showed that IGD is predicted only by burnout and gender (p < 0.001), Adjusted R² = 0.234. This study provides information for policy, prevention, and intervention purposes targeting burnout particularly among males who are a high-risk group. Additionally, this study contributes to possible joint online program development to reduce IGD among Japanese and Israeli gamers. Further research should examine the association between IGD and loneliness, controlling gender and other factors such as substance use, religiosity, eating behavior, depression, game genre, and motivation to play. Full article

The present study explores residents’ perceptions of Stintino (Sardinia, Italy) as a tourist destination. The municipality is predominantly known for La Pelosa beach, widely regarded as one of the most attractive coastal sites in Europe. However, its popularity has raised critical issues related to carrying capacity and seasonal overcrowding, contributing to a tourism model centered almost exclusively on beach-related activities. This study aims to investigate how locals conceptualize their place beyond the dominant seaside narrative, particularly considering Stintino’s identity as a former fishing village with a strong maritime tradition. As part of Italy’s designated inner areas, Stintino also embodies a deep-rooted connection to cultural heritage, further reinforcing the need for its preservation. Adopting a photovoice-based participatory visual methodology, this study engaged 15 local stakeholders from key sectors (hospitality, fishing tourism, retail, gastronomy, and cultural institutions) who produced and discussed photographic representations of their lived experience of the territory. The visual material was thematically analyzed using a conceptual framework informed by theories of place perception and social representations. The findings suggested a multifaceted territorial storytelling rooted in local heritage, symbolic spaces, and everyday practices. Tourism governance strategies could incorporate community-based approaches, such as participatory mapping and inclusive narrative development, to foster more sustainable and place-sensitive promotion models. Full article

In the period between 2021 and 2022 immediately following the COVID-19 lockdowns, there were 37 professional or academic productions of The Tempest in the United States. The play was by far the most produced of Shakespeare’s works in this timespan, and those 37 productions represent a 280% increase compared to 2019, in which there were 13 such productions. Considering The Tempest’s hyper-popularity within the context of the Black Lives Matter Movement and the birth of We See You White American Theatre’s calls for reform in 2020, this paper seeks to understand anew the way in which Shakespeare constructs blackness in the play. Indeed for all of its beauty and magic, The Tempest stages a violent anti-blackness in its treatment of Caliban. In particular, I argue an unexplored connection between The Tempest and Ben Jonson’s 1605 court masque, The Masque of Blackness, itself an exploration of the construction of race for a particular early modern audience. My exploration here began as a partial answer to a question posed by Robin Alfriend Kello: “how do you balance [an] attraction to the richness of Shakespearian verse against these layered histories of racial violence and exclusion?” A deeper understanding of Shakespeare’s version of blackness may grant insights into areas of intervention for those theaters reaching for The Tempest amidst national calls for anti-racist theatrical work. Full article

Smart home devices and home automation systems, which control features such as lights, blinds, heaters, door locks, cameras, and speakers, have become increasingly popular and can be found in homes worldwide. Central to these systems are smart home hubs, which serve as the primary control units, allowing users to manage connected devices from anywhere in the world. While this feature is convenient, it also makes smart home hubs attractive targets for cyberattacks. Unfortunately, the average user lacks substantial cybersecurity knowledge, making the security of these systems crucial. This is particularly important as smart home systems are expected to safeguard users’ privacy and security within their homes. This paper synthesizes eight prevalent cybersecurity challenges associated with smart home hubs through a systematic literature review. The review process involved identifying relevant keywords, searching, and screening 713 papers in multiple rounds to arrive at a final selection of 16 papers, which were then summarized and synthesized. This process included research from Scopus published between January 2019 and November 2024 and excluded papers on prototypes or individual features. The study is limited by scarce academic sources on open-source smart home hubs, strict selection criteria, rapid technological changes, and some subjectivity in study inclusion. The security of extensible smart home hubs is a complex and evolving issue. This review provides a foundation for understanding the key challenges and potential solutions, which is useful for future research and development to secure this increasingly important part of our everyday homes. Full article

In recent years, several emerging transport modes have appeared in cities all over the world and have been widely adopted by commuters and travelers. This leads to strong growth and popularity of multi-modal transport and Mobility as a Service (MaaS) in cities. These emerging transport modes have not only received much attention from service providers and practitioners but have also attracted researchers in related communities. These are reflected in the growing number of published papers related to research issues of multi-modal mobility transport in cities. The factors that have been driving the strong growth of the number of published papers related to the emerging multi-modal transport in cities are the deficiencies of effective solution methods to accommodate the needs of users in cities with multi-modal transport modes. Although the existing literature is still deficient in offering seamless end-to-end multi-modal mobility transport services, it provides valuable sources and clues for finding the potential future research subjects/issues/directions. In this study, we attempt to identify potential research directions based on a review of the existing literature on multi-modal mobility transport. By searching the WOS database, we analyze the profile and trends of research directions related to multi-modal mobility. The results of this study pave the way for the assessment of research subjects/issues/directions under the umbrella term of multi-modal mobility transport. This review paper significantly reduces the time required for readers to identify prospective research subjects, issues, or directions without delving into the literature. Full article