Description of a Dynamical Framework to Analyse the Helicopter Tail Rotor

In this work, a tail rotor is modelled with the aid of a multibody software to provide an alternative tool in the field of helicopter research. This advanced application captures the complex behaviour of tail rotor dynamics. The model has been built by using VehicleSim software (Version 1.0, Mechanical Simulation Corporation, Ann Arbor, MI, USA) specialized in modelling mechanical systems composed of rigid bodies. The dynamic behaviour and the control action are embedded in the code. Thereby, VehicleSim does not need an external link to another software package. The rotors are articulated, the tail rotor considers flap and feather degrees of freedom for each of the equispaced blades and their dynamic couplings. Details on the model’s implementation are derived, emphasising the modelling aspects that contribute to the coupled dynamics. The obtained results are contrasted with theoretical approaches and these have displayed to agree with the expected behaviour. This rotorcraft model helps to study the performance of a tail rotor under certain dynamic conditions.

Curating Quality? How Twitter’s Timeline Algorithm Treats Different Types of News

This article explores how Twitter’s algorithmic timeline influences exposure to different types of external media. We use an agent-based testing method to compare chronological timelines and algorithmic timelines for a group of Twitter agents that emulated real-world archetypal users. We first find that algorithmic timelines exposed agents to external links at roughly half the rate of chronological timelines. Despite the reduced exposure, the proportional makeup of external links remained fairly stable in terms of source categories (major news brands, local news, new media, etc.). Notably, however, algorithmic timelines slightly increased the proportion of “junk news” websites in the external link exposures. While our descriptive evidence does not fully exonerate Twitter’s algorithm, it does characterize the algorithm as playing a fairly minor, supporting role in shifting media exposure for end users, especially considering upstream factors that create the algorithm’s input—factors such as human behavior, platform incentives, and content moderation. We conclude by contextualizing the algorithm within a complex system consisting of many factors that deserve future research attention.

AN EXTENSION OF CITYJSON TO SUPPORT POINT CLOUDS

The combination between dense point clouds and 3D vector objects permits new cartographic representation of urban information. This paper proposes an extension for the CityJSON encoding to support point clouds. Following the 3.0 CityGML specifications, attributes and features are added to the core module of v1.0.1 CityJSON. Two solutions are proposed: inline complex geometries and external link to a remote file. The extended schema can be illustrated in four scenarios: detailed features visualization, fall-back solution in features reconstruction processes, simulating urban climate represented as vector fields, and true-to-life representation solution for complex elements such as solitary vegetation objects. It permits 3D city modelers to handle points clouds in a native way reducing files size and avoiding redundancy. All developments and documentation are available open-source.

Webometric Analysis of Institutional Repositories of Malaysian Public Universities

An institutional repository (IR) is one of the resources available in most university libraries that have attracted external publishers, search engines and social media to link, share and index IR content. The traditional citation-based indicators of a publication may not reflect the IR quality and have led to the creation of new indicators such as webometrics or web metrics. This study aims to analyse and explore Malaysia’s public university IR visibility, the numbers of an external link, page count, PDF count and URL web mention. We utilised backlinks web crawler and web search engine to collect raw data. A visualisation was created using the force-directed graphing method to interpret the IR network in the webspace. This study revealed that two research universities, Universiti Malaya (UM) and Universiti Putra Malaysia (UPM), dominate web visibility based on webometrics indicators. All non-research universities are at the bottom of the rankings. This study shows institutional repositories from research universities are more visible in academic social networks and digital library sites. In contrast, non-research universities need to improve their visibility by mapping the universities’ IRs websites through hyperlink exchange and collaboration activities between each university and promoting the university publication to the academic social network sites.

Impact of Mental Health Screening on Promoting Immediate Online Help-Seeking: Randomized Trial Comparing Normative Versus Humor-Driven Feedback

Background Given the widespread availability of mental health screening apps, providing personalized feedback may encourage people at high risk to seek help to manage their symptoms. While apps typically provide personal score feedback only, feedback types that are user-friendly and increase personal relevance may encourage further help-seeking. Objective The aim of this study was to compare the effects of providing normative and humor-driven feedback on immediate online help-seeking, defined as clicking on a link to an external resource, and to explore demographic predictors that encourage help-seeking. Methods An online sample of 549 adults were recruited using social media advertisements. Participants downloaded a smartphone app known as “Mindgauge” which allowed them to screen their mental wellbeing by completing standardized measures on Symptoms (Kessler 6-item Scale), Wellbeing (World Health Organization [Five] Wellbeing Index), and Resilience (Brief Resilience Scale). Participants were randomized to receive normative feedback that compared their scores to a reference group or humor-driven feedback that presented their scores in a relaxed manner. Those who scored in the moderate or poor ranges in any measure were encouraged to seek help by clicking on a link to an external online resource. Results A total of 318 participants scored poorly on one or more measures and were provided with an external link after being randomized to receive normative or humor-driven feedback. There was no significant difference of feedback type on clicking on the external link across all measures. A larger proportion of participants from the Wellbeing measure (170/274, 62.0%) clicked on the links than the Resilience (47/179, 26.3%) or Symptoms (26/75, 34.7%) measures (χ2=60.35, P<.001). There were no significant demographic factors associated with help-seeking for the Resilience or Wellbeing measures. Participants with a previous episode of poor mental health were less likely than those without such history to click on the external link in the Symptoms measure (P=.003, odds ratio [OR] 0.83, 95% CI 0.02-0.44), and younger adults were less likely to click on the link compared to older adults across all measures (P=.005, OR 0.44, 95% CI 0.25-0.78). Conclusions This pilot study found that there was no difference between normative and humor-driven feedback on promoting immediate clicks to an external resource, suggesting no impact on online help-seeking. Limitations included: lack of personal score control group, limited measures of predictors and potential confounders, and the fact that other forms of professional help-seeking were not assessed. Further investigation into other predictors and factors that impact on help-seeking is needed. Trial Registration Australian New Zealand Clinical Trials Registry ACTRN12616000707460; https://www.anzctr.org.au/ Trial/Registration/TrialReview.aspx?id=370187 (Archived by WebCite at http://www.webcitation.org/6y8m8sVxr)

Impact of Mental Health Screening on Promoting Immediate Online Help-Seeking: Randomized Trial Comparing Normative Versus Humor-Driven Feedback (Preprint)

BACKGROUND Given the widespread availability of mental health screening apps, providing personalized feedback may encourage people at high risk to seek help to manage their symptoms. While apps typically provide personal score feedback only, feedback types that are user-friendly and increase personal relevance may encourage further help-seeking. OBJECTIVE The aim of this study was to compare the effects of providing normative and humor-driven feedback on immediate online help-seeking, defined as clicking on a link to an external resource, and to explore demographic predictors that encourage help-seeking. METHODS An online sample of 549 adults were recruited using social media advertisements. Participants downloaded a smartphone app known as “Mindgauge” which allowed them to screen their mental wellbeing by completing standardized measures on Symptoms (Kessler 6-item Scale), Wellbeing (World Health Organization [Five] Wellbeing Index), and Resilience (Brief Resilience Scale). Participants were randomized to receive normative feedback that compared their scores to a reference group or humor-driven feedback that presented their scores in a relaxed manner. Those who scored in the moderate or poor ranges in any measure were encouraged to seek help by clicking on a link to an external online resource. RESULTS A total of 318 participants scored poorly on one or more measures and were provided with an external link after being randomized to receive normative or humor-driven feedback. There was no significant difference of feedback type on clicking on the external link across all measures. A larger proportion of participants from the Wellbeing measure (170/274, 62.0%) clicked on the links than the Resilience (47/179, 26.3%) or Symptoms (26/75, 34.7%) measures (χ2=60.35, P<.001). There were no significant demographic factors associated with help-seeking for the Resilience or Wellbeing measures. Participants with a previous episode of poor mental health were less likely than those without such history to click on the external link in the Symptoms measure (P=.003, odds ratio [OR] 0.83, 95% CI 0.02-0.44), and younger adults were less likely to click on the link compared to older adults across all measures (P=.005, OR 0.44, 95% CI 0.25-0.78). CONCLUSIONS This pilot study found that there was no difference between normative and humor-driven feedback on promoting immediate clicks to an external resource, suggesting no impact on online help-seeking. Limitations included: lack of personal score control group, limited measures of predictors and potential confounders, and the fact that other forms of professional help-seeking were not assessed. Further investigation into other predictors and factors that impact on help-seeking is needed. CLINICALTRIAL Australian New Zealand Clinical Trials Registry ACTRN12616000707460; https://www.anzctr.org.au/ Trial/Registration/TrialReview.aspx?id=370187 (Archived by WebCite at http://www.webcitation.org/6y8m8sVxr)

Drawing From Available Means: Assessing the Rhetorical Dimensions of Facebook Practice

A company’s presence on Facebook plays an important role in engaging its customer base. However, little empirical work has fully examined the nature and impact of corporate Facebook posts on engagement. In this study, we analyzed 680 Facebook posts collected from a sample of six companies over a period of 12 months. We examined variables including post frequency, content type, illocutionary act, linking style, and media. We found that entertainment posts were more engaging than operational news and innovation posts. Educational posts were also more engaging than innovation posts. With regard to illocutionary acts, expressives, or posts that express the writer’s emotion, were more engaging than all other illocutionary acts. Additionally, representative posts were more engaging than directive posts. For linking style, we discovered that posts containing no link were actually more engaging than posts with an external link. We also found a significant interaction between content type and linking practice, which indicates that linking style influences the effectiveness of some content types in engaging audiences. Finally, we found that companies overwhelmingly relied on the use of text and images in their posts over video and image galleries. We speculate that content that removes a user from the Facebook “universe” (e.g., a link or a video) actually may demotivate a user to engage with the original content of the post. We discuss these results from a rhetorical perspective and provide insight for corporate Facebook practices.