bluuebunny/crossref_metadata_2025 huggingface dataset:
Feasibility Evaluation of Metamaterial Microwave Sensors for Non-Invasive Blood Glucose Monitoring
Authors: Malena Lukas , Fiser Ondrej , Stauffer Paul R. , Drizdal Tomas , Vrba Jan , Vrba David
Published: October 2021

The use of microwave technology is currently under investigation for non-invasive estimation of glycemia in patients with diabetes. Due to their construction, metamaterial (MTM)-based sensors have the potential to provide higher sensitivity of the phase shift of the S21 parameter (∠S21) to changes in glucose concentration compared to standard microstrip transmission line (MSTL)-based sensors. In this study, a MSTL sensor and three MTM sensors with 5, 7, and 9 MTM unit cells are exposed to liquid phantoms with different dielectric properties mimicking a change in blood glucose concentration from 0 to 14 mmol/L. Numerical models were created for the individual experiments, and the calculated S-parameters show good agreement with experimental results, expressed by the maximum relative error of 8.89% and 0.96% at a frequency of 1.99 GHz for MSTL and MTM sensor with nine unit cells, respectively. MTM sensors with an increasing number of cells show higher sensitivity of 0.62° per mmol/L and unit cell to blood glucose concentration as measured by changes in ∠S21. In accordance with the numerical simulations, the MTM sensor with nine unit cells showed the highest sensitivity of the sensors proposed by us, with an average of 3.66° per mmol/L at a frequency of 1.99 GHz, compared to only 0.48° per mmol/L for the MSTL sensor. The multi-cell MTM sensor has the potential to proceed with evaluation of human blood samples.
Active Suspension Control Strategy of Multi-Axle Emergency Rescue Vehicle Based on Inertial Measurement Unit
Authors: Guo Qinghe , Zhao Dingxuan , Zhao Xiaolong , Li Zhenxing , Shi Xiaobo
Published: October 2021

Active suspension control strategies are a top priority in active suspension system. The current research on active suspension control strategies is mostly focused on two-axle vehicles, and there is less research investigating multi-axle vehicles. Additionally, their effective implementation is dependent on accurate mathematical models, and most of them adopt force feedback control, which is vulnerable to external interference. To solve these problems, this paper proposes an active suspension control strategy based on Inertial Measurement Unit. The multi-axle emergency rescue vehicle is made to be equivalent to a 3-degrees-of-freedom parallel mechanism by using the method of grouping and interconnecting the suspension units of the whole vehicle. The attitude change of the vehicle body was transformed into the servo actuator’s displacement by solving the inverse solution of the parallel mechanism position and the action of the servo actuator was driven in reverse according to the displacement obtained. In this way, the vehicle body attitude can be compensated, and the ride comfort and the handling stability of the vehicle can be improved. To verify the effectiveness of the control strategy proposed, the three-axle six vehicle was taken as the research object, the position inverse solution of its equivalent 3-degrees-of-freedom parallel mechanism was deduced, and a high-pass filter was designed. The three-axle vehicle experiment platform integrating active suspension and hydro-pneumatic suspension was built, and the gravel road and slope road experiments were carried out and the results compared with those obtained with hydro-pneumatic suspension. The experiment results showed that, compared with hydro-pneumatic suspension, the active suspension control strategy based on Inertial Measurement Unit proposed in this paper can not only stabilize the body attitude, but also effectively suppress body vibration, improving the ride comfort and handling stability of the vehicle significantly.
Sensors for Context-Aware Smart Healthcare: A Security Perspective
Authors: Batista Edgar , Moncusi M. Angels , López-Aguilar Pablo , Martínez-Ballesté Antoni , Solanas Agusti
Published: October 2021

The advances in the miniaturisation of electronic devices and the deployment of cheaper and faster data networks have propelled environments augmented with contextual and real-time information, such as smart homes and smart cities. These context-aware environments have opened the door to numerous opportunities for providing added-value, accurate and personalised services to citizens. In particular, smart healthcare, regarded as the natural evolution of electronic health and mobile health, contributes to enhance medical services and people’s welfare, while shortening waiting times and decreasing healthcare expenditure. However, the large number, variety and complexity of devices and systems involved in smart health systems involve a number of challenging considerations to be considered, particularly from security and privacy perspectives. To this aim, this article provides a thorough technical review on the deployment of secure smart health services, ranging from the very collection of sensors data (either related to the medical conditions of individuals or to their immediate context), the transmission of these data through wireless communication networks, to the final storage and analysis of such information in the appropriate health information systems. As a result, we provide practitioners with a comprehensive overview of the existing vulnerabilities and solutions in the technical side of smart healthcare.
Two-Step Approach to Processing Raw Strain Monitoring Data for Damage Detection of Structures under Operational Conditions
Authors: Ren Peng , Zhou Zhi
Published: October 2021

Strain data of structural health monitoring is a prospective to be made full use of, because it reflects the stress peak and fatigue, especially sensitive to local stress redistribution, which is the probably damage in the vicinity of the sensor. For decoupling structural damage and masking effects caused by operational conditions to eliminate the adverse impacts on strain-based damage detection, small time-scale structural events, i.e., the short-term dynamic strain responses, are analyzed in this paper by employing unsupervised modeling. A two-step approach to successively processing the raw strain monitoring data in the sliding time window is presented, consisting of the wavelet-based initial feature extraction step and the decoupling step to draw damage indicators. The principal component analysis and a low-rank property-based subspace projection method are adopted as two alternative decoupling methodologies. The approach’s feasibility and robustness are substantiated by analyzing the strain monitoring data from a customized truss experiment to successfully remove the masking effects of operating loads and identify local damages even concerning accommodating situations of missing data and limited measuring points. This work also sheds light on the merit of a low-rank property to separate structural damages from masking effects by comparing the performances of the two optional decoupling methods of the distinct rationales.
Separation and Disinfection of Contagious Aerosols from the Perspective of SARS-CoV-2
Authors: Brouwers J. J. H.
Published: October 2021

An assessment was performed on methods of separating and disinfecting airborne droplet nuclei containing viruses, such as SARS-CoV-2. The droplet nuclei originate from evaporating aerosols emitted by the coughing, singing, sneezing, etc. of infected humans. Based on empirical data and theoretical analysis, we successively determined: (i) the particle number distribution of nuclei versus the nucleus diameter, (ii) the statistical distribution of the viral content in the droplet nuclei starting from a uniform random distribution of viruses in the mucus, (iii) the particle number distribution of droplet nuclei containing at least one virus particle, and (iv) the effectiveness of methods for removing and disinfecting nuclei containing one or more virus particles from indoor air; viz., ventilation with fresh air, filtering with porous media, such as HEPA, and centrifugal separation and simultaneous disinfection, particularly with a rotational particle separator (RPS). Indoor aerosol removal with RPS supplemented with HEPA to arrest tiny volumes of very small particles was found to be the most effective. It is as good as particle removal through ventilation with clean air over long periods of time. An RPS facilitates direct elimination of viruses in the collected nuclei by flushing with a disinfection liquid. The components of an RPS are recyclable. Combining HEPA with an RPS extends the service time of HEPA by almost two orders of magnitude compared to the relatively short service time of stand-alone HEPA filters.
Comparison between Mid-Infrared (ATR-FTIR) Spectroscopy and Official Analysis Methods for Determination of the Concentrations of Alcohol, SO2, and Total Acids in Wine
Authors: Dini Irene , Di Lorenzo Ritamaria , Senatore Antonello , Coppola Daniele , Laneri Sonia
Published: October 2021

The determination of alcohol, SO2, and total acids in wine through conventional laboratory techniques have some limitations related to the amount of the samples, analytical preparation of laboratory staff, and time to carry out the analysis. In recent years, spectroscopic and chromatographic methods have been proposed to determinate simultaneously multiple analytical parameters. The new methods claim the speed of analysis and easy execution. However, they need a validation process that guarantees the reliability of the results to be used in official determinations. This study aimed to evaluate the usefulness of FT-infrared reflectance (FT-IR) to quantify total acid, alcohol, and SO2 concentration in the wines. For this purpose, 156 DOC Italian wines were tested with IR technology, and results were compared to those obtained by official analysis methods. The comparison was performed using two non-parametric statistical methods: the Bland & Altman test and Passing & Bablok regression. Our results showed that the spectrophotometric methods make errors due to interfering contaminants in the sample that can be corrected by blank determination. Therefore, the spectrophotometric methods that use the infrared region of the electromagnetic spectrum can be used by the wine industry and regulators for the wine routine as an alternative to official methodologies.
Dream It, Do It? Associations between Pornography Use, Risky Sexual Behaviour, Sexual Preoccupation and Sexting Behaviours among Young Australian Adults
Authors: Clancy Elizabeth Mary , Howard Dominika , Chong Shaoyuan , Klettke Bianca
Published: October 2021

While sexting behaviours have attracted increasing research focus over the last decade as both normative and deviant forms of sexual activity, little attention has been paid to their potential associations with sexual preoccupation and heightened interest in sex. The current study sought to identify whether sexual preoccupation significantly predicts sending, receiving, and disseminating sexts, after controlling for pornography use and risky sexual behaviours. Young Australian adult participants (N = 654, 78.8% women) aged 18 to 34 (M = 19.78, SD = 1.66) completed an anonymous online self-report questionnaire regarding their engagement in sexting behaviours (sending, receiving, and dissemination), pornography use, risky sexual behaviours, and sexual preoccupation. Results showed that individuals with higher sexual preoccupation were more likely to engage in pornography use and risky sexual behaviours. Binary hierarchical logistic regressions revealed that sexual preoccupation predicted higher rates of sending and receiving sexts. However, sexual preoccupation did not significantly contribute to increased rates of sext dissemination. Our study illustrates the need to incorporate pornography viewing and sexting into the promotion of safe sexual behaviours in online and offline contexts, and the potential to utilise modern technology to negotiate safer sex practices.
Scaling Up Smart City Logistics Projects: The Case of the Smooth Project
Authors: Sista Eleonora , De Giovanni Pietro
Published: October 2021

A large number of smart city logistics projects fail to scale up, remaining a local experimental exercise. This lack of scalability is, in fact, commonly recognized as a major problem. This study aims to determine the key success factors related to the scalability of smart city logistics projects. The process of scaling up, which is articulated as expansion, roll-out, and replication, is defined as the ability of a system to improve its scale by aiming to meet the increasing volume demand. Specifically, this study investigates the scalability intended to be used as expansion and roll-out. A qualitative case study was conducted to fulfill the research purpose. The chosen case study is SMOOTh, a pilot project currently underway in the city of Gothenburg, Sweden, involving a diverse group of companies including Volvo Group and DHL. Semi-structured interviews were conducted with seven of the project’s stakeholders. Through a thematic analysis, four categories and the respective success factors were identified. These were represented by a business model, as well as technical, stakeholder and regulatory factors. The paper concludes with observations and recommendations aimed at the pilot initiatives, adding new perspectives to the upscaling debate.
Cheating under the Circumstances in Marital Relationships: The Development and Examination of the Propensity towards Infidelity Scale
Authors: Lișman Carmen Gabriela , Holman Andrei Corneliu
Published: October 2021

Most of the previously developed scales addressing infidelity were developed on young samples in dating relationships and with limited couple experience. The present study proposes an instrument to measure the proneness for infidelity among married people with substantial experience as a couple. Specific contexts described by the items, in which unfaithful behavior might occur, were selected from those revealed by previous research on people’s motives of past infidelity. Across two studies (N = 618) we examined the factorial structure and the psychometric characteristics of the Propensity towards Infidelity Scale (PTIS). Results revealed a one-dimensional structure of the PTIS and supported its reliability, its construct, criterion and incremental validity. PTIS emerged as negatively associated with two measures of adherence to moral standards, and positively related to past unfaithful behavior. Furthermore, the new instrument was found to bring a significant contribution in explaining these behaviors beyond two other scales of infidelity intentions.
Trends in Educational and Skill Mismatch in the United States
Authors: Shin Dong-Hoon , Bills David
Published: October 2021

We examined trends in the incidence and correlates of educational and skill mismatch in the United States. We focused on trends over time in the associations between various types of mismatch and a range of factors including contextual conditions. We explored whether contextual conditions at the transitional period from school to jobs increase or decrease the probability of mismatch and whether such relationships persist throughout the working career. Our central questions were how the incidence of and relationship between educational and skill mismatch in the U.S. changed between 1994, 2003, and 2012 and how this differed by age, gender, immigration status, educational attainment, and occupation. We used three cross-sectional surveys that had not previously been implemented for such an effort. These were the International Adult Literacy Survey (IALS) in 1994, the Adult Literacy and Life-skills (ALL) survey in 2003, and the Program for the International Assessment of Adult Competencies (PIAAC) in 2012. Repeated cross-sectional data provided us with substantial analytic leverage. Our findings point toward the key role of occupational or positional factors rather than individual worker characteristics as being most implicated in trends in mismatch. We describe the importance of our results for labor market theories.
Adolescent Perspectives on How an Adjunctive Mobile App for Social Anxiety Treatment Impacts Treatment Engagement in Telehealth Group Therapy
Authors: Lu Celine , Chu Wendy , Madden Shannon , Parmanto Bambang , Silk Jennifer Susan
Published: October 2021

Adjunctive mobile mental health apps to supplement mental health treatment have been growing in recent years given their ability to address treatment engagement barriers. However, few studies have explicitly examined how these mobile apps impact treatment engagement, and even fewer have investigated this topic through adolescents’ perspectives. To this end, we conducted semi-structured interviews with five adolescents who used an adjunctive mobile mental health app in combination with telehealth cognitive behavioral group therapy for social anxiety. Using a multidimensional framework of treatment engagement, we elicited their perspectives on how the app impacted their engagement in telehealth group therapy and gathered their suggestions for improving the app. Using a consensual qualitative research approach, we learned that adolescents felt the app increased their comfort with others in therapy and their expectations about the effectiveness of mental health apps. They also indicated that the app prepared them for in-session participation and facilitated out-of-session skills practice. Adolescents had valuable suggestions such as adding app features to facilitate social connectedness between group members and adding appointment reminders in the app. This preliminary study highlights implications for future adjunctive mobile mental health app developers and researchers to increase adolescents’ treatment engagement in mental health services.
How Does Voluntary Contact with the Police Produce Distrust? Evidence from the French Case
Authors: Le Franc Victor , Spire Alexis
Published: October 2021

Drawing on quantitative and qualitative data, this article points out the effects that instances of contact with the police can produce on the relationship with this public institution. The quantitative analysis highlights that trust in the police depends on social variables, such as political orientation, level of resources, age, and religion, but also on the frequency of direct contact with this institution. Being summoned to a police station is significantly associated with distrust in the police, and self-initiated contacts also promote distrust toward the police. Our qualitative data, collected through participant observation and interviews, provide a further insight into these results. The interaction between the police and governed people has two dimensions that may explain the production of distrust. On the one hand, the interaction involves a relationship of domination by the police, which is manifested by a demand on the part of the police for docility from the complainants. On the other hand, it involves a relationship of service, which gives rise to an expectation of recognition on the part of governed people, an expectation that is rarely satisfied. These everyday interactions do not necessarily translate into judgments about the fairness of police officers. Such feelings of frustration and dispossession should be taken into consideration in understanding how trust is affected by these voluntary contacts.
Harvest Rates of Rheophilic Fish Vimba vimba, Chondrostoma nasus, and Barbus barbus Have a Strong Relationship with Restocking Rates and Harvest Rates of Their Predator Silurus glanis in Lowland Mesotrophic Rivers in Central Europe
Authors: Lyach Roman
Published: October 2021

The European catfish Silurus glanis (Linnaeus, 1758) is an expanding apex piscivorous predator whose predation may drive fish harvest rates and fish populations. This study aimed to analyze the relationships between intensive catfish stocking/harvesting and harvest rates of putative catfish prey–three rheophilic fish species: vimba bream Vimba vimba, nase Chondrostoma nasus, and barbel Barbus barbus (Linnaeus, 1758). The GAM (generalized additive model) was used to analyze the relationships between the harvest rate and the stocking intensity rate of the catfish and the three rheophilic fish species. The harvest rates and stocking intensity rates were obtained from mandatory angling logbooks collected from 38,000 individual recreational anglers by the Czech Fishing Union on 176 fishing sites over the years 2005–2017 in central Bohemia and Prague (the Czech Republic). Our results show that a higher intensity of catfish stocking and harvesting resulted in a lower harvest rate of rheophilic fishes. Conversely, the stocking rates of rheophilic fishes were not significantly correlated to their harvest rates. In conclusion, a significant negative relationship was found between the harvest rate and the restocking rates of rheophilic fishes and their predator, suggesting that fisheries managers should not perform intensive stocking of both catfish and rheophilic fishes on the same rivers.
Preparing for the Worst? Household Food Stockpiling during the Second Wave of COVID-19 in Serbia
Authors: Ben Hassen Tarek , El Bilali Hamid , Allahyari Mohammad S. , Berjan Sinisa , Karabašević Darjan , Radosavac Adriana , Dašić Goran , Đervida Ružica
Published: October 2021

Stockpiling and panic buying are significant components of crisis- and disaster-related consumption behaviors that have gained significant media coverage during the COVID-19 pandemic. This paper aims to analyze the features of stockpiling behavior during the second wave of COVID-19 in Serbia based on a structured online questionnaire. This study seeks to answer two questions. First, what factors triggered and affected stockpiling during the COVID-19 pandemic in Serbia? Second, how does stockpiling affect other food habits and diets? A total of 851 valid responses were received. The results highlight several features of the stockpiling behavior in Serbia. First, food stockpiling behavior is influenced by some sociodemographic variables such as gender and household composition. Second, stockpiling was fueled by several negative emotions such as fear, sadness, and depression. Third, the results confirm that stockpiling in Serbia was not triggered by supply shortages but rather by consumers’ concerns of obtaining enough food and rising food prices. Finally, food stockpiling was associated with some positive changes such as eating out less (e.g., restaurants/cafeteria), eating more with their family members, and cooking more food. Analyzing and comprehending consumer food stockpiling patterns during the COVID-19 pandemic may offer policymakers imperative information for adjusting supply and response strategies during future crises.
Spatial Distribution of Public Housing and Urban Socio-Spatial Inequalities: An Exploratory Analysis of the Valencia Case
Authors: Gallego-Valadés Alfonso , Ródenas-Rigla Francisco , Garcés-Ferrer Jorge
Published: October 2021

The urban spatial distribution of public housing is not a widely addressed issue in Spain, from a geographical perspective. This paper analyses the spatial distribution of public housing in the city of Valencia (Spain), as well as to identify its relationship with other socio-residential characteristics of the urban environment. Different techniques of spatial point pattern analysis, exploratory spatial data analysis (ESDA) and clustering methods are implemented. We analyse both the univariate spatial patterns of public housing and its relationship with two variables: a low-income population and median monthly rent. Analysis has revealed that public housing follows a pattern of partial agglomeration and mostly peripheral dispersion in its spatial distribution. However, there does not seem to be a univocal and immanent relationship between such distribution patterns and the characteristics of the socio-residential environment. Conversely, it is possible to point to the existence of multiple local forms of association. The lack of a clear pattern may be due to many reasons: the heterogeneity of profiles eligible for public housing, the size of the projects and the spatial dispersion in their location.
Business Intelligence and Business Value in Organisations: A Systematic Literature Review
Authors: Paradza Dignity , Daramola Olawande
Published: October 2021

Organisations must derive adequate business value (BV) from Business Intelligence (BI) adoption to retain their profitability and long-term sustainability. Yet, the nuances that define the realisation of BV from BI are still not understood by many organisations that have adopted BI. This paper aims to foster a deeper understanding of the relationship between Business Intelligence (BI) and business value (BV) by focusing on the theories that have been used, the critical factors of BV derivation, the inhibitors of BV, and the different forms of BV. To do this, a systematic literature review (SLR) methodology was adopted. Articles were retrieved from three scholarly databases, namely Google Scholar, Scopus, and Science Direct, based on relevant search strings. Inclusion and exclusion criteria were applied to select ninety-three (93) papers as the primary studies. We found that the most used theoretical frameworks in studies on BI and BV are the Resource-Based View (RBV), Dynamic Capabilities Theory (DCT), Technology-Organisation-Environment (TOE), and Contingency Theory (CON). The most acknowledged critical factors of BV are skilled human capital, BI Infrastructure, data quality, BI application and usage/data culture, BI alignment with organisational goals, and top management support. The most acclaimed inhibitors of BV are data quality and handling, data security and protection, lack of BI Infrastructure, and lack of skilled human resource capital, while customer intelligence is the most acknowledged form of BV. So far, many theories that are relevant to BI and BV, critical factors, inhibitors, and forms of BV were marginally mentioned in the literature, requiring more investigations. The study reveals opportunities for future research that can be explored to gain a deeper understanding of the issues of BV derivation from BI. It also offers useful insights for adopters of BI, BI researchers, and BI practitioners.
Environmental and Economic Impact of Retrofitting Techniques to Prevent Out-of-Plane Failure Modes of Unreinforced Masonry Buildings
Authors: Giresini Linda , Casapulla Claudia , Croce Pietro
Published: October 2021

This paper presents an innovative methodology to assess the economic and environmental impact of integrated interventions, namely solutions that improve both structural and energy performance of existing masonry buildings, preventing out-of-plane modes and increasing their energy efficiency. The procedure allows the assessment of the environmental and the economic normalized costs of each integrated intervention, considering seismic and energy-saving indicators. In addition, the work introduces in relative or absolute terms two original indicators, associated with seismic displacement and thermal transmittance. The iso-cost curves so derived are thus a powerful tool to compare alternative solutions, aiming to identify the most advantageous one. In fact, iso-cost curves can be used with a twofold objective: to determine the optimal integrated intervention associated with a given economic/environmental impact, or, as an alternative, to derive the pairs of seismic and energy performance indicators associated with a given budget. The analysis of a somehow relevant case study reveals that small energy savings could imply excessive environmental impacts, disproportionally increasing the carbon footprint characterizing each intervention. Iso-cost curves in terms of absolute indicators are more suitable for assessing the effects of varying acceleration demands on a given building, while iso-cost curves in terms of relative indicators are more readable to consider a plurality of cases, located in different sites. The promising results confirm the effectiveness of the proposed method, stimulating further studies.
Assessment of Morphological Traits, Nutritional and Nutraceutical Composition in Fruits of 18 Apricot cv. Sekerpare Clones
Authors: Karatas Neva , Ercisli Sezai , Bozhuyuk Mehmet Ramazan
Published: October 2021

Apricot (Prunus armeniaca L.) is one of the most important members of Prunus and its trees bears delicious and nutritious fruits during summer months in the temperate zones in the world. Apricot cultivars are propagated asexually which consists of clones. Information on inter-clonal variations in apricot cultivars can assist us in the selection of better clones from commercial cultivars. We aimed to determine morphological traits (fruit weight, seed weight, kernel weight, flesh/seed ratio, shape index, fruit firmness, color index), nutritional (sugars and organic acids) and nutraceutical (total phenolic, total flavonoids, total carotenoid and antioxidant activity) composition of 18 clones of Sekerpare apricot cultivar grown together in Kagizman district in eastern Turkey. Results showed significant differences among clones concerning most of the morphological traits, nutritional and nutraceutical compositions. Fruit weight, flesh/seed ratio and fruit firmness of clones were in range of 23.14–27.11 g, 11.21–13.14 and 3.88–5.11 kg/cm2, respectively. Fruit shape index was slightly similar among all clones which was between 0.95 and 1.03. Citric acid and sucrose were found to be the predominant organic acid and sugar among clones which varied from 728 to 915 mg/100 g and 7.11 to 9.94 g/100 g, respectively. The clone ‘KS2’ exhibited the highest level of total phenol (67.1 mg gallic acid equivalent per 100 g) and antioxidant activity (2.16 μmol trolox equivalent per g). The study confirmed the diversity among Sekerpare clones and effectiveness of combining morphological, nutritional and nutraceutical analyses in assessment of Şekerpare clones and its use for future pre-breeding programs.
Effects of Autogenous and Stimulated Self-Healing on Durability and Mechanical Performance of UHPFRC: Validation of Tailored Test Method through Multi-Performance Healing-Induced Recovery Indices
Authors: Cuenca Estefanía , Lo Monte Francesco , Moro Marina , Schiona Andrea , Ferrara Liberato
Published: October 2021

Chloride diffusion and penetration, and consequently chloride-induced corrosion of reinforcement, are among the most common mechanisms of deterioration of concrete structures, and, as such, the most widely and deeply investigated as well. The benefits of using Ultra-High Performance (Fiber-Reinforced) Concrete—UHP(FR)C to extend the service life of concrete structures in “chloride attack” scenarios have been addressed, mainly focusing on higher “intrinsic” durability of the aforementioned category of materials due to their compact microstructure. Scant, if nil, information exists on the chloride diffusion and penetration resistance of UHPC in the cracked state, which would be of the utmost importance, also considering the peculiar (tensile) behavior of the material and its high inborn autogenous healing capacity. On the other hand, studies aimed at quantifying the delay in chloride penetration promoted by self-healing, both autogenous and autonomous, of cracked (ordinary) concrete have started being promoted, further highlighting the need to investigate the multidirectional features of the phenomenon, in the direction both parallel and orthogonal to cracks. In this paper, a tailored experimental methodology is presented and validated to measure, with reference to its multidirectional features, the chloride penetration in cracked UHPC and the effects on it of self-healing, both autogenous and stimulated via crystalline admixtures. The methodology is based on micro-core drilling in different positions and at different depths of UHPC disks cracked in splitting and submitted to different exposure/healing times in a 33 g/L NaCl aqueous solution. Its validation is completed through comparison with visual image analysis of crack sealing on the same specimens as well as with the assessment of crack sealing and of mechanical and permeability healing-induced recovery performed, as previously validated by the authors, on companion specimens.
Does COVID-19 Affect Safety and Security Perception in the Hospitality Industry? A Romanian Case Study
Authors: Szentesi Silviu Gabriel , Cuc Lavinia Denisia , Feher Andrea , Cuc Paul Nichita
Published: October 2021

The objective of the article is to analyze, based on social exchange theory, the different risk and safety perceptions of employees and customers in the hospitality industry regarding the protections against the SARS-CoV-2 pandemic in an emerging market, namely in Romania. To this end, a questionnaire was administered simultaneously to both categories in Romanian hospitality units obtaining a sample of 561 employees and customers in the sector. While the emergence of SARS-CoV-2 virus has generated a lot of diverse research, studies focused on this particular topic, also regarding both customers and employees, were much less exploited. Therefore, eleven working hypotheses were formulated. It was highlighted that there is a positive perception of safety at work for employees, and jobs are protected from disappearance due to the pandemic through active measures taken by the organization. Employees do not show a significant desire to change jobs due to the new working conditions. The magnitude of safety measures taken had a positive impact on the customers, and customers do not pose a significant threat in hospitality industry units regarding the possibility of infection with the SARS-CoV-2 virus. The paper enlarges the understanding of behavioral effects of the SARS-CoV-2 pandemic, while from a managerial perspective the results are particularly useful for hospitality industry owners in order to attract and retain employees and to communicate and develop better relations with customers.
Analizing Teens an Analysis from the Perspective of Gamers in Youtube
Authors: Lozano-Blasco Raquel , Latorre-Martínez Mᵃ Pilar , Cortes-Pascual Alejandra
Published: October 2021

(1) Gamers are a new social phenomenon on YouTube whose success is based on their humour and social identity. The aim of this research is to deepen the understanding of the behaviour of the 100 gamers with the largest numbers of fans worldwide by studying their channels on YouTube; (2) Methods: This is a longitudinal research study from 20/08/2019 to 20/08/2020. The methodology consists of three techniques: social media analysis, opinion mining or sentiment analysis, and qualitative semantic analysis; (3) Results: The results of regression and KPI analysis confirm that the most popular contents have high levels of humour, positive polarity, irony, and subjectivity. In addition, the jargon of the digital community is used, focusing on group identification; (4) Conclusions: We conclude that teenagers use YouTube to search content that is cheerful, fun, and with high doses of humor and irony, in which gamers narrate their own vision of reality. Understanding these characteristics makes it possible to adapt educational channels to the interests of the adolescent community. At the same time, it allows us to understand how group identity is constructed in the virtual community, being able to establish lines of intervention from the educational and family orientation.
Development of Eco-Friendly Mortars Produced with Kaolin Processing Waste: Durability Behavior Viewpoint
Authors: Rodrigues Alisson Mendes , Costa Fabiana Pereira da , Beltrão Suellen Lisboa Dias , Fernandes Jucielle Veras , Menezes Romualdo Rodrigues , Neves Gelmires de Araújo
Published: October 2021

This study presents the development of new eco-friendly mortar compositions containing kaolin residues (KR) and assesses their durability behavior. Firstly, the natural and calcinated kaolin residues (600 °C, 650 °C, 700 °C, 750 °C, and 800 °C) were characterized by X-ray diffraction (XRD), differential thermal analysis (DTA), granulometric analysis, and surface area. The kaolin residue calcinated at 800 °C was chosen to be added to new compositions of mortar because it presented the best pozzolanic performance. The aging tests accomplished in internal (Ei) and external (Ee) environments were applied in mortars with a mass proportion of 1:2:6 (cement + KR: lime: sand), in which the KR, calcinated at 800 °C, replaced the cement in the mass fraction of 0%, 5%, 10%, 15%, 20%, and 30%. The Ei was performed for 30, 60, 90, 180, and 360 days, and the Ee for 90; 210; 360; and 512 days. After the aging tests were completed, the mortar compositions containing KR were evaluated to determine their mineralogical phases (XRD), compressive strength (CS), and thermal behavior (DTA and thermogravimetry). In summary, the KR addition to the mortar compositions decreases the mechanical resistance to compression; however, mortars with a substitution of 10% and 20% presented resistance values within the minimum limit of 2.4 MPa established by ASTM C 270.
Experience Sharing on Virtual COOP Training to Mechanical Engineering Students during the COVID-19 Pandemic
Authors: Mohammed Abdul Samad
Published: October 2021

The COVID-19 pandemic, which started in December 2019, brought about a paradigm shift in the lifestyles of people worldwide due to the imposed constraints and lockdowns aimed at containing the spread of the infection. Each and every aspect of our lifestyle such as eating, travelling, socializing and learning was affected by this pandemic. Even the education sector was not untouched due to this pandemic, which caught the various stakeholders of this industry, such as the students, faculty and the administration, unaware. The education of a complete generation of kids and adults all over the world required some drastic adjustments so that their learning process would continue unaffected. Even though distance learning and online teaching have been around for a long time in the education sector, its importance was felt during this last year because of the role it played in the transfer of knowledge to students during the lockdowns wherein the students did not have access to physical classrooms and schools. Faculty, students and the administration developed new innovative ideas to adjust to this new change in teaching/learning styles and made the transition for all stakeholders a smooth and an enlightening experience. One such change had to be made in the delivery style of the cooperative program (COOP) for Mechanical engineering students at King Fahd University of Petroleum and Minerals (KFUPM). COOP is a 9-credit hour course that a student with a junior standing in the Applied Mechanical Engineering program (AME) has to take and pass. It requires the student to spend about seven months in the industry to learn applications in a practical environment and solve practical problems with the aid of the theoretical knowledge gained by him in the courses. However, due to the sudden lockdown in March 2020, most of the industries downed their shutters, which left these poor students halfway stranded through their COOP course. Hence, in order to cater to these students, the administration came up with the idea of substituting physical training with virtual training without compromising on the quality of the education. Comprehensive procedures on the various modules designed and delivered under this new virtual training program, the mode of instruction used, the assessment methods implemented and the experiences of the students are presented in this paper, which can be of tremendous help to various stakeholders.
Health Implications of Judo Training
Authors: Drid Patrik , Franchini Emerson , Lopes-Silva João Paulo , Fukuda David H. , Wells Adam J. , Lakicevic Nemanja , Bianco Antonino , Paoli Antonio , Milovancev Aleksandra , Roklicer Roberto , Trivic Tatjana
Published: October 2021

Although current physical activity (PA) guidelines regarding aerobic and anaerobic training are helpful for the population at large, many individuals prefer to engage in alternative forms of PA such as combat sports. As both a martial art and sport, judo is a physically demanding form of PA that potentially offers a novel experience, consequently leading to greater PA adherence. This study aimed to thoroughly search the existing literature to determine the health benefits of judo-specific training. PubMed and Web of Science were searched for original research studies. Only peer-reviewed studies that examined the effects of judo training in males and females aged 18–35 were included in the study. Out of 507 potentially relevant studies, 84 studies met our inclusion criteria and were further analyzed. Data showed that judo athletes and recreational judo practitioners show above-average VO2max, improved body composition, increased bone mineral density, and bone mineral content. Judo is associated with a sequence of adaptations in cardiac structure, function, and blood pressure changes. More research is needed to discover if these changes are maladaptive.
Citizens or Consumers? Air Quality Sensor Users and Their Involvement in Sensor.Community. Results from Qualitative Case Study
Authors: Wróblewski Michał , Suchomska Joanna , Tamborska Katarzyna
Published: October 2021

This article presents the results of the qualitative research conducted on Polish users of the Sensor.Community network. Different types of motivation behind the decision to engage in the collection of air quality data are discussed. Users’ motives have been found to result predominantly from the concern for the health and safety of their loved ones, as well as the need to control air quality (and ultimately the quality of life) in their immediate environment (home and neighbourhood). Users do not display civic behaviour such as working for the local community. Three factors have been proposed to explain this status quo. First, the motives related to health and safety, as opposed to motives behind seeking a resolution to an environmental problem at the local level, may contribute to the solidification of individualistic attitudes. Second, Sensor.Community is organised in a way that does not promote a greater involvement from the network organisers in the development of the initiative and retention of users. Instead, the network focuses predominantly on the technical aspects of operation. Third, users have no sense of agency as, in our opinion, they remain largely unaware of the value of the data they collect.
Study on Rural Residents’ Satisfaction with the Clean Energy Heating Program in Northern China—A Case Study of Shandong Province
Authors: Liu Xingmin , Qin Beibei , Wu Yong , Zou Ran , Ye Qing
Published: October 2021

The Chinese government announced the Clean Energy Heating Program in northern China in 2017, promoting clean energy for residents’ winter heating. The key difficulty of implementing this policy initiative lies in rural areas. This research hence focuses on evaluating the implementation of this policy in rural areas. Rural residents who directly benefit from, and are integrally involved in, the implementation process in Shandong Province were surveyed to evaluate their satisfaction with this policy. In order to identify their satisfaction indicators and obstacle factors, a TOPSIS obstacle model adjusted by entropy weight was developed. An evaluation system of the indicators of residents’ satisfaction with the policy was developed and converted into a questionnaire. The designed questionnaire was distributed to 341 rural residents in Jinan, Zibo and Heze in Shandong province. Data analysis suggests that, at the fiscal subsidies level, supporting infrastructure, technical supports and support organizations are four important factors affecting rural residents’ satisfaction. The key obstacle factors identified include technical support, supporting infrastructure, the operation subsidies level, heating cost, period of subsidies and achieved temperature. Corresponding suggestions for further clean energy heating policy design and implementation in rural areas in northern China are provided.
Systematic Review of Informal Urban Economies
Authors: Thulare Mpendulo Harold , Moyo Inocent , Xulu Sifiso
Published: October 2021

Amid globalization and market liberalization, urban informality has continued to grow in leaps and bounds in many parts of the world. Against this backdrop, the purpose of this paper is to provide a systematic review of studies conducted on urban economic informality at various geopolitical contexts to provide an update on the current state of knowledge in the urban informal economy-related research. A total number of 290 studies were sourced from various academic sources; however, a total number of 166 research papers satisfied the requirements of this review paper. The findings of this paper show that research on the urban informal economy has grown from 2000 to 2021, which is a 22-year period in which this review paper was based. The main themes of urban economic informality research depict it as a multifaceted system that is constituted by inputs, processes and outputs that have linkages with the formal economy. Based on these findings, it is recommended that more research should focus on how to integrate research on urban economic informality into the broader agenda of sustainable development.
Mapping 30 Years of Sustainability of Solar Energy Research in Developing Countries: Indonesia Case
Authors: Madsuha Alfian Ferdiansyah , Setiawan Eko Adhi , Wibowo Nurhadi , Habiburrahman Muhammad , Nurcahyo Rahmat , Sumaedi Sik
Published: October 2021

Research into converting solar light energy into electricity using so-called photovoltaic (PV) technology or solar cells (SCs) was started a long time ago. However, most developing countries tend to lag behind. The present work delivers a bibliometric mapping analysis of 30 years of Indonesian solar energy research papers in the Scopus database. A multidisciplinary point of view is used to cover the findings comprehensively, highlighting the emerging gaps, orientation, and promising future research that will benefit many researchers, governments, and industry. Two essential keywords, “photovoltaic” and “solar cell”, were used to harvest the data. A total of 1886 documents were finally investigated. The VOSviewer was utilized as a proper complement for visualizing and analyzing the publication trends based on the keywords and authorships. Many aspects of solar research have been explored, including the basic science of semiconductors, simulation, lab-scale device fabrication, and the application of technologies and policies. The findings show that the two keywords determined the research characteristics. It also reveals that the geographical location had a remarkable impact on publication distribution. The most striking result is that a minimum of 1146 documents are centralized on Java Island. In addition, the policies related to renewable energy show a strong impact: two years after the policies were announced, the publications exhibited a two-fold increase. The results also suggest that future research should focus on the increasingly significant domestic component of silicon-based solar cells, the various multidisciplinary approaches for making PV utilization more affordable, and on shifting towards the use of perovskite solar cells. Solid national and international collaboration should be continued for the sustainability of Indonesian solar energy research.