Shaking Table Tests on Seismic Deformation of Composite Breakwaters

A series of shaking table tests were conducted on composite breakwater systems under 30g centrifugal conditions. The emphasis was placed on investigating the mechanisms of seismic settlement of foundation ground, in particular of the contribution from the dispersion of mound rubble into the foundation soil. In-flight visual observation of the deformation process by a high-speed CCD camera showed the significance of cumulative vertical compression of foundation soils under cyclic loading. Pre- and post-shaking comparisons of weight of the rubble mound revealed that dispersion into the soil had occurred and contributed to caisson settlement

Empirical essays on the roles of news media in an urban economy

Economists typically assume perfect information, but households are not always well informed, and face a high degree of uncertainty regarding the quality of goods or value of their assets. As a consequence, information from mass media is a main part of our everyday lives. Coverage in popular media outlets can catch the attention of millions of households and, therefore, news media may influence their decisions in several ways. This thesis investigates the roles of news media in an urban economy and for housing markets. Each of the three empirical essays provides insights into how information from the media can shape the economic decisions of households as either homebuyers, homeowners, or consumers. While the first and the second chapters estimate the causal effects of publicity, in particular positive information, on house prices and non-housing consumption, respectively, the last chapter explores how media coverage may affect the link between house prices and homeowner spending. This thesis places particular emphasis on understanding the mechanisms through which news media may affect economic outcomes by empirically identifying potential channels

Korean Parents' and Adolescents' Reports of Parenting Styles: A Developmental Study

The main purpose of this study was to examine differences and relations among Korean mothers', fathers', and adolescent girls' and boys' reports of parenting styles, distinguishing possible differences in early and mid-adolescence. The following five parenting factors were assessed: warmth/affection, aggression/hostility, neglect/rejection, behavioral control, and psychological control. Differences in individuals' adherence to cultural values as well as the relations among cultural values and parenting styles were examined. Results revealed differences within and across parents' and adolescents' reports of parenting styles. For example, mothers were more warm, aggressive/hostile, behaviorally controlling, and psychologically controlling than fathers. Boys also reported more parental behavioral control and neglect/rejection than girls. Developmental comparisons showed that younger adolescents and their parents reported the use of more parental behavioral control than older adolescents and their parents. Comparisons with regard to the relations among parenting styles showed that behavioral control is not always positively associated with warmth among Koreans. More specifically, maternal behavioral control was associated with maternal warmth for boys, but not for girls. In addition, psychological control was not a consistent negative predictor of warmth among Koreans. For example, adolescents' perceptions of maternal psychological control negatively predicted warmth for older, but not younger adolescents. Assessments also revealed that parents adhered more to Asian cultural values than their adolescent children. Cultural values moderated the relations among parental dimensions of warmth and control. For example, fathers with high adherence to Asian cultural values associated expressions of behavioral control with those of warmth. Fathers with low adherence to Asian cultural values, however, associated expressions of behavioral control with both warmth and aggression/hostility. Overall, differences in reports of parenting styles as well as differences in the relations among cultural values and parenting styles for mothers, fathers, and adolescent boys and girls revealed the complexity in the forms and functions of parenting styles among Koreans. Results also revealed the importance of examining developmental differences in parental expressions and adolescents' perceptions of parenting styles

Disclosure of suicidal drivers on social media: a natural language processing and thematic analysis approach

It is common for people to search for health information on the internet, share their health issues through social media, and ask for advice from people in online communities. Some people reported feeling more comfortable sharing their psychological stress online and anonymously asking for advice from people. As such, people disclose not only their suicide risk but also their suicidal risk-associated drivers (e.g., suicide ideation, relational stress, financial crisis). This study aims to identify suicidal drivers from narratives extracted from social media, synthesize findings and suicide theories, and provide insights into future suicide prevention policies and practices. This research gathered and analyzed 128,587 posts written by 76,547 people worldwide. The posts were written in English from January 2021 to December 2022 on the r/SuicideWatch of Reddit. Natural Language Processing and topic modeling, specifically Latent Dirichlet Allocation (LDA), were used to identify clusters of posts based on similarities and differences between posts. Thematic analysis was used to identify suicidal drivers across clusters of posts. The web crawler developed by Brandwatch was used in data collection, and Python was used for all analyses.  Six theme clusters of posts were identified. The first theme was Disclosure of Repetitive Suicide Ideation (i.e., “I want to die. I want to die, I want to die…(repeated)”), and 36.4% of posts had this theme. The second theme was Disclosure of Relational Stress (i.e., “I don’t have any friends”), and 31.9% of posts had this theme. The third theme was Disclosure of Suicide Attempts and Negative Healthcare Experiences (i.e., “I’ve had a suicide attempt before”, “The nurses ignored me”), and 9.9% of posts had this theme. The fourth theme was Disclosure of Abuse (i.e., “He would beat me black and blue”), and 8.8% of posts had this theme. The fifth theme was Disclosure of Contextual Stress, including finance and legal matters (i.e., “every moment was a living fear of the debt collector knocking on the door”), and 7.2% of posts had this theme. The last theme was Philosophical and Informative Discussions around suicide (i.e., “After death, the physical begins to deteriorate and life/energy is simply moved to another being”), and 5.8% of posts had this theme. Understanding different suicidal drivers is an essential component in designing individualized intervention plans for people at suicide risk. The current research identified the idiosyncrasies in the suicide drivers people talked about when disclosing their suicidality. Furthermore, the findings from this study’s data-inspired and exploratory approach provided additional evidence supporting existing suicide theories and frameworks. This research has the potential to lay the groundwork for designing suicide intervention strategies that target individuals’ self-disclosures of their struggles online

USA educator perspectives regarding the nature and value of social and emotional learning

This paper discusses the US educator perspectives regarding the nature and value of Social Emotional Learning (SEL) skills. This research is part of a larger study being conducted by 33 career development investigators from 15 countries. SEL skills are becoming increasingly critical to helping youth develop the competencies needed to become employable within the emergent 4th Industrial Revolution. Today’s youth must articulate how their competencies align to multiple career opportunities. They need relationship skills and social awareness to interact with different managers and work environments. Youth need self-management skills to advance in the workplace and engage in lifelong learning. For this study, educators were asked to provide written responses to a series of open-ended questions about their understanding of SEL, their perspective on SEL’s relevance to their own effectiveness as educators, and whether and how they perceive SEL as relevant to teaching in classroom settings. This paper will report on the results of how U.S. educators perceive the value and relevance of SEL. Using a modified grounded theory approach, responses from 40 educators were analyzed and 123 SEL themes emerged. The results will be discussed in relation to existing SEL and career readiness frameworks.First author draf

FiFo: Fishbone Forwarding in Massive IoT Networks

Massive Internet of Things (IoT) networks have a wide range of applications, including but not limited to the rapid delivery of emergency and disaster messages. Although various benchmark algorithms have been developed to date for message delivery in such applications, they pose several practical challenges such as insufficient network coverage and/or highly redundant transmissions to expand the coverage area, resulting in considerable energy consumption for each IoT device. To overcome this problem, we first characterize a new performance metric, forwarding efficiency, which is defined as the ratio of the coverage probability to the average number of transmissions per device, to evaluate the data dissemination performance more appropriately. Then, we propose a novel and effective forwarding method, fishbone forwarding (FiFo), which aims to improve the forwarding efficiency with acceptable computational complexity. Our FiFo method completes two tasks: 1) it clusters devices based on the unweighted pair group method with the arithmetic average; and 2) it creates the main axis and sub axes of each cluster using both the expectation-maximization algorithm for the Gaussian mixture model and principal component analysis. We demonstrate the superiority of FiFo by using a real-world dataset. Through intensive and comprehensive simulations, we show that the proposed FiFo method outperforms benchmark algorithms in terms of the forwarding efficiency.Comment: 13 pages, 16 figures, 5 tables; to appear in the IEEE Internet of Things Journal (Please cite our journal version that will appear in an upcoming issue.

Predictors of teacher burnout during the COVID-19 pandemic with machine learning

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