Mobile Context Research Articles

Spatio-temporal clustering of lumbar intervertebral flexion interactions in 127 asymptomatic individuals

The purpose of this study was to categorize asymptomatic participants based on the clustering of spatial and temporal intervertebral kinematic variables during lumbar flexion. Lumbar segmental interactions (L2-S1) were evaluated in 127 asymptomatic participants during flexion using fluoroscopy. First, four variables were identified consisting of: 1. Range of motion (ROMC), 2. Peaking time of the first derivative for separate segmentation (PTFDs), 3. Peaking magnitude of the first derivative (PMFD), and 4. Peaking time of the first derivative for stepwise (grouped) segmentation (PTFDss). These variables were used to cluster and order the lumbar levels. The number of participants required to constitute a cluster was chosen as 7. Participants formed eight (ROMC), four (PTFDs), eight (PMFD), and four (PTFDss) clusters, which included 85%, 80%, 77%, and 60% of them, respectively, according to the above features. For all clustering variables, angle time series of some lumbar levels showed significant differences between clusters. However, in general, all clusters could be categorized based on the segmental mobility contexts into three main groups as incidental macro clusters: the upper (L2-L4 > L4-S1), middle (L2-L3 < L3-L5 > L5-S1) and lower (L2-L4 < L4-S1) domains. There are spatial and temporal segmental interactions and between-subject variability in asymptomatic participants. In addition, the differences in angle time series among the clusters have provided evidence of feedback control strategies, while the stepwise segmentation facilitates consideration of the lumbar spine as a system and provides supplementary information about segmental interactions. Clinically, these facts could be taken into account when considering any intervention, but especially fusion surgery.

Transformation and recognition: Planning just climate havens in New York State

Climate change is altering the context of human mobility due to disasters such as sea-level rise, forest fires, and other extreme events. It is also changing how places plan and adapt to these chaotic events. In this paper we examine how climate destinations, or host communities, are preparing for potential climate related in-migration in their climate adaptation planning. While no place will be left untouched by climate change, a number of cities and communities across Upstate New York consider themselves “climate havens” due to their lower risk to many climate impacts, such as sea level rise, access to freshwater resources, and infrastructure to accommodate growth. Within this context, what does it mean to plan a just climate haven? What types of policy and planning might be needed? How are planners and practitioners framing adaptation approaches? Using Q-methodology, we reveal two dominant perspectives among planners and activists in Upstate New York on how to plan just climate havens. The first is a transformational view that looks to address the social, political, and economic drivers of vulnerability. The second is a recognition view that looks to address legal and legislative shortcomings in how to support climate migrants. Points of consensus on how to build just climate havens between the two groups include co-production and co-design, workforce development, food security, and safe and affordable housing. We suggest that these two perspectives frame justice in two distinct—but overlapping—ways and provide a shared basis on how to consider planning a just climate haven.

Bibliometric analyses and network mapping on the smart library in Web of Science from 2003 to 2021

PurposeThis research conducts bibliometric analyses and network mapping on smart libraries worldwide. It examines publication profiles, identifies the most cited publications and preferred sources and considers the cooperation of the authors, organizations and countries worldwide. The research also highlights keyword trends and clusters and finds new developments and emerging trends from the co-cited references network.Design/methodology/approachA total of 264 records with 1,200 citations were extracted from the Web of Science database from 2003 to 2021. The trends in the smart library were analyzed and visualized using BibExcel, VOSviewer, Biblioshiny and CiteSpace.FindingsThe People’s Republic of China had the most publications (119), the most citations (374), the highest H-index (12) and the highest total link strength (TLS = 25). Wuhan University had the highest H-index (6). Chiu, Dickson K. W. (H-index = 4, TLS = 22) and Lo, Patrick (H-index = 4, TLS = 21) from the University of Hong Kong had the highest H-indices and were the most cooperative authors. Library Hi Tech was the most preferred journal. “Mobile library” was the most frequently used keyword. “Mobile context” was the largest cluster on the research front.Research limitations/implicationsThis study helps librarians, scientists and funders understand smart library trends.Originality/valueThere are several studies and solid background research on smart libraries. However, to the best of the author’s knowledge, this study is the first to conduct bibliometric analyses and network mapping on smart libraries around the globe.

A Quantitative Positive Energy District Definition with Contextual Targets

This paper presents the goals and components of a quantitative energy balance assessment framework to define Positive Energy Districts (PEDs) flexibly in three important contexts: the context of the district’s density and local renewable energy supply (RES) potential, the context of a district’s location and induced mobility, and the context of the district’s future environment and its decarbonized energy demand or supply. It starts by introducing the practical goals of this definition approach: achievable, yet sufficiently ambitious, to be inline with Paris 2050 for most urban and rural Austrian district typologies. It goes on to identify the main design parts of the definition—system boundaries, balancing weights, and balance targets—and argues how they can be linked to the definition goals in detail. In particular, we specify three levels of system boundaries and argue their individual necessity: operation, mobility, and embodied energy and emissions. It argues that all three pillars of PEDs, energy efficiency, onsite renewables, and energy flexibility, can be assessed with the single metric of a primary energy balance when using carefully designed, time-dependent conversion factors. Finally, it is discussed how balance targets can be interpreted as information and requirements from the surrounding energy system, which we identify as a “context factor”. Three examples of such context factors, each corresponding to the balance target of one of the previously defined system boundaries, operation, mobility, and embodied emissions, are presented: density (as a context for operation), sectoral energy balances and location (as a context for mobility), and an outlook on personal emission budgets (as a context for embodied emissions). Finally, the proposed definition framework is applied to seven distinct district typologies in Austria and discussed in terms of its design goals.

Product information failures on websites and their impact on mobile shopping behaviour

PurposeInaccurate product information on retail websites lead to dissatisfied customers and profit losses. Yet, the effects of product information failures (PIFs) remain under-explored, with the mobile commerce channel commonly overlooked. This paper aims (1) to investigate the negative effects of PIFs on shoppers' attitudes and behaviours in a mobile context. The authors further (2) evaluate the impacts of the cause and duration of a PIF, changes of expectations towards the retailer after a PIF occurred and how previous mobile shopping experience in general decreases the effects of PIFs.Design/methodology/approachThe authors conducted a scenario-based experiment with a one-factorial between-subjects design. The six most common PIFs of an international leading online fashion retailer are operationalized and tested against a control group. The final sample consists out of 758 mobile shoppers from the UK.FindingsThe results demonstrate that the perceived severity of PIFs based on showing customers incorrect information is higher when key information is lacking. Further, when the cause of a PIF is attributed to the retailer, it results in higher recovery expectations towards them. The results also reveal that respondents who have shopped mobile before perceive PIFs as less severe than inexperienced ones.Originality/valueThis research expands the online service failure literature by examining PIFs and its effects in the specific context of mobile commerce. The authors also provide recommendations for a better management of PIFs like the incorporation of PIFs information into reporting packs.

A New Objective Function for RPL Based on Combined Metrics in Mobile IoT

To satisfy the quality of service requirements for some applications in the Internet of Things (IoT) network with mobile nodes, routing protocols must be adaptable to make better routing decisions. Routing Protocol for Lowpower and Lossy Networks (RPL) is one of the routing protocols that support metrics and constraints while building a Destination Oriented Directed Acyclic Graphs (DODAG) using a specific Objective Function (OF). However, RPL metrics that use standard OFs do not guarantee the performance criteria for a specific mobile IoT in terms of received and lost packets, overhead, throughput and power consumption. In this paper, we propose a new version of mrhof based on a combination of metrics such as total energy, the number of neighbors, and expected transmission count (ETX) to evaluate RPL performances in a mobile context. Then, we compare the assessment of this function to existing OFs based on various mobility models (Random Waypoint (RWP), Reference Point Group Mobility (RPGM), Nomadic) and node densities. The results show that this new function is more efficient than the standards OF in terms of packets received and packets lost with Random Way Point and RPGM models. Regardless of the number of nodes, it also reduces ETX and traffic overhead for all mobility models, as well as convergence time in the Random Waypoint environment. Furthermore, this new function contributes to the improvement of Rtmetric, the enhancement of throughput at low density only in favor of RWP and RPGM models, and an effective power consumption reduction through all densities and mobility models.

Wind dynamic and energy-efficiency path planning for unmanned aerial vehicles in the lower-level airspace and urban air mobility context

Unmanned aerial vehicles (UAVs) have been extensively used in urban environments for logistics, parcel delivery and surveillance, and the development of air taxi services. Given the dynamic nature of urban air mobility in terms of decision-making time limit, wind dynamics and other external factors, one should consider their safe and efficient operations in an urban context. Therefore, we propose an energy-efficient path-planning model for UAVs under large and complex urban environments and wind dynamics. The proposed method adopted Voronoi Diagram to decompose the complex urban environment into a simplified network model, given the presence of no-fly zones and restricted areas as obstacles. One could obtain the feasible initial path by solving the network model using the Dijkstra shortest path algorithm concerning the distance matrix. Given the nonlinearity of energy consumption along a path. We further model the UAV energy consumption and propose an efficient particle swarm optimisation (PSO) metaheuristic algorithm to achieve better solution quality. Compared to traditional PSO, the proposed algorithm achieved a 5% to 22% improvement under different wind scenarios by simulating real-life situations. In conclusion, the proposed method can achieve safe UAV operations with sufficient separation and less energy consumption.

Habitus and migratory capitals of Haitians in Paraná. Educational trajectory and professional insertion in mobility contexts

Resumo Este artigo analisa a trajetória de pequeno grupo de haitianos que concluíram cursos superiores na Universidade Federal do Paraná (UFPR), entre 2019 e 2021. Em termos concretos, examinamos a relação entre habitus e capitais de cada migrante que frequentou as aulas de português, concluiu os cursos superiores e iniciou sua carreira profissional. A seleção dos entrevistados foi realizada a partir da base de dados de alunos imigrantes e refugiados disponibilizada pela Pró-Reitoria de Assuntos Estudantis da UFPR. Como referencial teórico, utilizamos os conceitos de habitus imigrante e capital migratório, desenvolvidos a partir da Teoria da Prática (Pierre Bourdieu, 1930-2002). Em síntese, percebe-se que aqueles imigrantes providos de habitus adequados e de capitais específicos foram mais exitosos em seus percursos educacionais e inserção no mercado de trabalho.

Adaptation to the Context in M-Learning Application Using Mobile Design Patterns

The fast progress of mobile devices and the popularity of mobile applications in the market requires complex software to be run on mobile devices without issues. Mobile devices are known as handhelds and they have different characteristics such as size, resolution, battery life and processing power. These are limitations to consider when developing an M-learning application, which can make it difficult to design and develop mobile applications for different mobile devices. Design Patterns, a set of tried and tested solutions for common problems were originally designed for desktop computers, so application of these patterns in M-learning applications might not meet its requirements such as adaptation of the content to the context of the device mobile used by learners. However, mobile design patterns that have been adapted or designed for such an environment can be used to overcome the challenges and limitations of M-learning application development. In this paper we try to propose an approach to engineering design patterns allowing the development of M-learning applications to provide an adapted content taking into account the context of device mobile used by learners. We named these patterns: “Mobile design patterns”.

Understanding of the dynamics of mobile reading: An HMM model of user engagement and content consumption

AbstractUnderstanding consumers’ engagement and subsequent content consumption behavior in the mobile context is critical to mobile app providers. In this paper, we develop a Hidden Markov Model (HMM) to capture the dynamics of users’ engagement states and consumption decisions on the number of books/chapters read and the amount of money spent. Our method allows us to simultaneously capture three interdependent usage behaviors using a single integrated model and identify the impact of content loading time and previous reading behavior on users’ engagement dynamics and content consumption. We calibrate the model using a tap stream data set of individual users’ reading activities on a mobile app. Our analysis reveals three distinct engagement states, a low state with inactive users, a medium state with users sampling books, and a high state with users reading intensively. Furthermore, we find that content loading time has higher negative impacts on high‐state users in state transitioning than medium‐state users. In contrast, the days that elapsed since the last visit has a similar negative impact on the users in the high and medium states. The effect of usage frequency on users in state transitioning is always positive. We have also identified the weekend effect and social influence on users’ reading outcomes. Finally, our simulations quantify the shortened content loading time and the days elapsed since the last visit on users’ engagement dynamics and content consumption decisions, which generate important managerial implications for app providers.

Guest editorial: Living in a “bubble”: global working communities and insulation in mobile contexts

Guest editorial: Living in a “bubble”: global working communities and insulation in mobile contexts

Assessment of sound propagation for the urban air mobility

The noise generated by vertical takeoff and landing vehicles (VTOL) operating in urban environnement is a determinant factor for the community acceptance. The ray-tracing method used for predicting road and raylway noise in urban areas can also be applied to the Urban Air Mobility context. In densely populated urban area, the multipath of sound wave occurs due to numerous reflections on the buildings walls. Such a configuration generates both constructive and destructive interferences, given rise to a complex shape of the spectra, that can be difficult to explain. To assess ray codes dedicated to road noise for this kind of configurations, simple test cases such as a corner and a canyon based on image sources are proposed. The prediction is performed in octave bands in the frequency range 63 Hz to 8000 Hz, including acoustical source at high altitudes to account for the VTOL flight. A good agreement is found between the reference solution derived from the image-source and the ray tracing technique. In particular close to the corner a significant increase of about 9 dB can be found. When both the source and the microphone are in the canyon, an inscrease up to 14dB can be found.

Bosnian-Herzegovinian Citizens in the Making – The Citizenship Debate in the Time of Social Mobilizations

AbstractDrawing upon rhetorical approaches to citizenship, this article analyzes how the contested notion of Bosnian-Herzegovinian (BiH) citizenship has been crafted on the discursive level during two series of social mobilizations taking place in 2013 and 2014. It aims to provide a better understanding of how various actors make sense of BiH citizenship. This study investigates what values were associated with citizenship, how boundaries of membership were drawn, and how the ethno-national dimension and linguistic complexities came into play. It analyzes a corpus of 150 media articles covering the protests in four major printed daily newspapers while methodologically relying on the discourse historical approach developed by Reisigl and Wodak. The analysis demonstrates that discursive articulations of citizenship are generated within the immediate context of social mobilization but are also influenced by historical legacies, institutional preconditions, regional aspects or global narratives. It shows that the decentralized institutional set up combined with the multi-layered and multidimensional meaning of citizenship blur the notion of BiH citizenship as an all-encompassing term and pose an obstacle to the formulation of an alternative vision of the BiH polity to the post-Dayton order.

Differentiation in Protest Politics: Participation by Political Insiders and Outsiders

The political participation literature has documented a long-term trend of the normalization of noninstitutional participation that is often equated with the conventionalization of engagement in protest politics. Less is known on the extent to which noninstitutional forms are differentiated by their mobilization context. Population surveys find it difficult to contextualize individual engagement, and on-site surveys point to effects that are hard to generalize. This study fills this gap by emphasizing differentiation and distinguishing participation according to the issue of engagement. It introduces a conceptual distinction between political insiders and outsiders, defined based on the extent to which they are embedded in the organizational landscape of the dominant cleavage dimension. Using an original survey conducted in Germany during the Covid-19 crisis, the analysis demonstrates that general-population surveys are fit to examine issue-specific participation patterns. The results expose an insider and outsider divide, captured by the effect of attitudinal and behavioral indicators, and demonstrates that the two groups are equally likely to participate in noninstitutional forms. However, insiders engage on the established issues of climate and anti-racism, whereas outsiders engage on the new issues of Covid-19 related economic assistance and civil liberties restrictions. In addition, dynamic models reveal that noninstitutional participation is rooted in volatile issue preferences. Overall, the paper argues that participation during the Covid-19 crisis has furthered the trend towards a differentiated protest arena.

Measures of the Slovak Republic to improve military mobility for the needs of military Schengen

Military mobility in Europe (so-called Military Schengen) is a critical issue in collaboration with countries interested in defense. NATO and the EU decided to cooperate closely in this area and jointly proposed measures to improve military mobility. The transportation of military personnel and equipment across borders is a sensitive policy area, and, consequently, today, a range of physical, legal and regulatory barriers impede military mobility in Europe. Slovakia represents a critical transit point for military transfers, and its participation in this area is essential. The article described the strategic importance of military mobility and the context of military mobility in Slovakia. The main goal was to point out the current situation of military mobility in Europe, analyze requirements and provide an evaluation of their fulfilment in Slovakia, which led to the creation of recommendations in four points in the conclusion.

Predicting safety performance on motorways during the pandemic based on geometric design: A case study in Portugal

The mobility restrictions due to the covid-19 pandemic have created an unprecedented situation in the road system. Declared lockdowns have significantly altered the traffic volumes and perhaps also driver behavior. This study conducts research on crashes occurred on motorway A29 in Portugal before and during the disrupted mobility context. Safety performance functions were adjusted with negative binomial distribution. The segmentation was based on horizontal alignments. 5 of the 27 variables initially considered were found to be significant; namely traffic volume, segment length, curvature change rate, presence of deceleration lane and year. The quality of the fitted models was verified using cumulative residuals plots. The results showed that a traditional statistical modelling approach explains accident occurrence in a similar way before and during the pandemic.

Climate mobilities, rights and justice: Complexities and particularities

Climate mobility revolves around issues of justice and human rights, whether this be concerning its causes, expression or handling. This paper examines the justice-rights nexus as it relates to climate mobility, highlighting how the two spheres converge and diverge. It works with four case studies exploring the complexity of rights and justice in the climate mobility context. Our case studies are diverse, in terms of the mobility types concerned and the rights and justice-based issues involved. We show that conceptualizing or achieving just or righteous outcomes is neither certain nor a uniform pursuit when it comes to climate mobility. Rather, there are many divergences–by those who claim rights or justice, and those asked to respond. We present a complex and contested space, highlight the importance of approaching justice and rights matters contextually, and with special attention to particularities when climate mobility is at issue.

Race and Occupational Mobility in the National Football League

The Rooney Rule was implemented in the National Football League (NFL) in 2003 to increase levels of employment for ethnic-minority coaches by requiring teams within the league to interview candidates of color for head coaching and executive level positions. However, only three coaches of color were employed at the beginning of the 2020 season. Framed within the larger context of occupational mobility, the present study aims to identify mobility trends for white coaches and coaches of color and analyzes the root causes for the difficulties that candidates of color experience when seeking higher-level positions within NFL organizations. Results illuminate a variety of institutional issues that exist within the NFL and allow for the development of recommendations that are useful for scholars and practitioners alike.

The meaning of citizenship: Identifying the beliefs of teachers responsible for citizenship education in Chile

ABSTRACT Based on evidence from a 2019 survey of a sample of Chilean secondary education teachers responsible for citizenship education, this article examines their beliefs regarding citizenship and how these beliefs relate to their justifications of both legal and illegal protest actions in a societal context of wide socio-political crisis and mobilization. Using exploratory factor analysis, two types of citizenship are identified as structuring the beliefs of teachers: duty-based citizenship, related to what the literature conceives of as a minimalist or personally responsible-type of citizen, and activism-based citizenship, or the citizen type defined in the literature as justice-oriented. Then, exploring bivariate correlations with teachers’ justification of different protest actions, we found that duty-based citizenship beliefs are related to a pattern in which protest (legal or illegal) is considered less justifiable, whereas activism-based beliefs correlate positively with a greater justification of both legal and illegal (blockades of streets and strikes) protest actions. We examine these findings, distinguishing between teachers’ beliefs and justifications as educators and as citizens, arguing that the context of socio-political crisis and mobilization is a key factor for interpreting the tensions and dilemmas of teaching citizenship in Chile.

Immigration Enforcement Effects and the Role of School Social Workers Supporting Immigrant Students

This mixed-methods study examines school social workers’ perceptions of immigration enforcement on the lives of immigrant students. The article builds upon previous sociological and education research about how the contexts of reception impact immigrant mobility, immigration enforcement, and the role of school-based personnel support for immigrant students. The paper examines the relationship between 517 school social workers’ perception of the effects of immigration enforcement and their actions to improve equity for immigrant students. Relationships are compared using multiple regression analysis with and without state fixed effects. Findings reveal significant differences across some of the key constructs and relationships. Implications are discussed for school social workers in U.S. schools as they continue to promote equity for immigrant students.