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Skill formation and the trouble with child noncognitive skill measures
No full textThis paper develops a framework to address issues of contamination in parent-reported measures of child noncognitive skills. We estimate a dynamic model in which child and parental skills evolve jointly and leverage information provided by teachers and interviewers to deal with contamination of parent-reported measures. The model also allows us to examine the relative importance of mothers and fathers in the evolution of child skills. Our findings reveal that ignoring contamination significantly underestimates the role of maternal non-cognitive skills in the evolution of child noncognitive skills. Additionally, we find evidence of stronger feedback effects from child skills to mothers than fathers. Simulation exercises demonstrate how contamination can distort evaluations of early childhood policies, underscoring the importance of robust measurement approaches
Hearing attitudes: tone of voice and its effects on listeners’ wellbeing and disclosure
Get PDFThis thesis investigates how speakers’ vocal expressions shape listeners’ affective and behavioural responses across interpersonal, workplace, and cross-cultural contexts. Specifically, it addresses three key research questions. First, how might a speaker’s interested-sounding voice elicit listeners’ disclosure and wellbeing differently than an uninterested-sounding voice, and how do these outcomes vary across cultures? (Chapter 2). Second, do differing voice patterns influence work commitment, state of wellbeing, and flourishing among listeners? (Chapter 3). Third, what psychological impacts, disclosure responses, and affective states arise when listeners are exposed to varying voice patterns across real-life contexts? (Chapter 4). The overarching aim of this thesis is to examine how the nuances of vocal tone (beyond the semantic language) affect relational dynamics, emotional states, and behavioural outcomes. Employing both experimental and cross-cultural methodologies, the studies provide empirical evidence that vocal tone not only communicates affect but also carries the power to shape disclosure, wellbeing, and commitment in diverse settings
An Improved Aggregation-Based Signcryption for Secure Drone to Ground Station Communication System
Get PDFSecure and efficient communication in drone-assisted networks is critical for maintaining the integrity
of cyber-physical systems. This paper presents a rigorous cryptographic analysis of an existing
aggregation-based signcryption scheme, revealing key vulnerabilities, including susceptibility to
forgery, impersonation attacks, and inconsistencies in key generation and verification processes. To
overcome these limitations, we propose a novel aggregation-based signcryption framework built upon
hyperelliptic curve cryptography (HECC), offering enhanced security and lightweight computation.
The proposed scheme is formally proven to satisfy fundamental cryptographic properties, including
confidentiality, authentication, integrity, unforgeability, and impersonation resistance under the
hardness assumption of the hyperelliptic curve discrete logarithm problem (HECDLP). Performance
evaluation demonstrates that our approach achieves up to 36% reduction in computational cost and
12% lower communication overhead compared to the schemes of Verma et al. [1], Aithekar et al. [2],
and Ali et al. [3]. These results confirm the practical applicability of our design for secure and efficient
drone-to-ground station communication in resource-constrained environments
Four-Year Longitudinal Associations Between Effort in Physical Education Classes and Fitness Outcomes in UK Adolescents
Get PDFBackground: Student engagement and effort in physical education (PE) can influence long-term physical fitness development. This study examined whether self-reported effort in PE (ePE) predicts changes in physical fitness among English secondary school students. Methods: A 4-year longitudinal study involved 1422 adolescents from 9 public schools in the East of England. Assessments took place at years 7, 9, and 11 (year 7 = 12 [0.5] y), measuring aerobic fitness, muscular strength, and muscular power. ePE was self-reported using the Physical Activity Questionnaire for Adolescents. Latent growth curve models examined changes in fitness over time, and whether these associations were modified by sex, body mass index (BMI), or socioeconomic status (via Index of Multiple Deprivation). Results: Girls had lower baseline fitness and smaller gains over the 4-year period than boys across aerobic fitness, muscular power, and muscular strength. Higher baseline BMI and living in a disadvantaged area were associated with lower initial fitness, and changes in BMI influenced longitudinal changes in fitness. Baseline ePE positively predicted all baseline fitness measures, with aerobic fitness showing the strongest association. Change in ePE over time was the strongest predictor of improvements across all fitness components. Conclusion: Effort in PE classes supports long-term fitness development. Interventions that encourage students to be active and engaged in PE may benefit all adolescents, especially girls and those with higher BMI or from disadvantaged areas. These findings highlight the value of promoting effortful participation in PE to enhance adolescent health and physical fitness
OTFS-based Integrated Positioning and Communication Systems with Low-Resolution ADCs
Get PDFThis paper proposes a two-phase orthogonal time–frequency space (OTFS)-based integrated positioning and communication (IPAC) framework under realistic low-resolution analog-to-digital converters (ADCs). In the uplink phase, the positioning signal is used to estimate channel parameters, which are subsequently used to determine the user’s position. The spatial smoothing-multiple signal classification algorithm is introduced to estimate the angle-of-arrival, whereas an iterative interference cancellation scheme is conceived for the remaining parameters’ estimation. The corresponding Cramer–Rao lower bounds of channel parameters and user position are also derived. During the downlink communication phase, the estimated parameters are exploited to improve beamforming at the base station. Simulation results evaluate the impact of ADC quantizer resolutions. Specifically, it is shown that enhanced downlink bit error rate performance can be achieved with improved uplink positioning, while the use of low-resolution ADCs induces noticeable performance degradation in the OTFS-IPAC system
Increased benthic biodiversity and food web recovery after decommissioning of oil and gas infrastructure
Get PDFThere is a global increase in the decommissioning of offshore oil and gas (O&G) infrastructure at the end of its operating lifetime. However, there is strikingly limited empirical evidence for the environmental and ecological impacts of decommissioning. Here, we employed a meta-analytical approach on an industry benthic monitoring database to investigate the benthic biodiversity and food web properties of structures sampled in the short term ( 5 yr; scenario 3) after decommissioning. We found reduced species richness and simplified food webs in scenario 1, followed by the first signs of recovery in scenario 2, with a slightly higher proportion of intermediate species and density of food web connections. Food webs recovered further in scenario 3, with a much greater density of interactions, but also more links and longer food chains, while a reduction in generalism and connectance indicated an increased prevalence of specialist species. Our findings demonstrate disturbance risks associated with the decommissioning process in the short term, but a positive recovery trajectory over longer timescales. We highlight the importance of industry collecting more extensive and long-term data at multiple time points and covering different decommissioning types, establishing a standardized data workflow for integrating with available monitoring efforts, and improving stakeholder participation and data accessibility to support an environmentally sound decommissioning process
Universal Costas Matrices: Towards a General Framework for Costas Array Construction
Get PDFCostas arrays are a special type of permutation matrices with ideal autocorrelation and low cross-correlation properties, making them valuable for radar, wireless communication, and integrated sensing and communication applications. This paper presents a novel unified framework for analyzing and discovering new Costas arrays. We introduce Universal Costas Matrices (UCMs) and Universal Costas Frequency Matrices (UCFMs) and investigate their structural characteristics. A framework integrating UCMs and UCFMs is proposed to pave the way for future artificial intelligence-assisted Costas array discovery. Leveraging the structural properties of UCMs and UCFMs, a reconstruction-based search method is developed to generate UCMs from UCFMs. Numerical results demonstrate that the proposed approach significantly accelerates the search process and enhances structural insight into Costas array generation
The Dollar's Double Life: Not All Dollar Appreciations Are Born Equal for the Cross-Currency Basis
Get PDFThis paper revisits the relationship between the US dollar and cross-currency basis (XCB) swap spreads. We show that the strength and direction of this relationship depend on the prevailing regime of the broad dollar. The evidence suggests that the well-documented “dollar appreciates, basis widens” result holds primarily when the dollar is in a low or intermediate regime. However, once the dollar transitions into a high regime, this association either weakens or reverses: a stronger dollar no longer widens the basis and may tighten it. Our findings reveal that not all dollar appreciations are created equal. For the same magnitude of dollar appreciation, basis spreads tend to widen significantly more in low- or intermediate-dollar regimes than in high-dollar regimes. We explain these results through a theoretical framework grounded in hedging demand and supply imbalances and validate them empirically using the term structure of XCB swap spreads of G10 currencies
New Constructions of Asymptotically Optimal Zero/Low Ambiguity Zone Sequence Sets
Get PDFSequences exhibiting zero/low ambiguity zone (ZAZ/LAZ) properties play an important role in contemporary communication and radar systems, particularly in Integrated Sensing and Communication (ISAC), which is an emerging wireless technology by sharing the hardware and bandwidth to perform these two tasks simultaneously. By incorporating nonlinear mapping and parity adaptive factor to design novel exponential functions, this letter proposes three methods for constructing ZAZ/LAZ sequence sets with new parameters. The resulting sequences are cyclically distinct and asymptotically optimal with respect to theoretical bounds
Chilling Effect and Fake News Laws: Lessons from East and Southeast Asia
No full textSo-called “fake news laws” refer to legislation that criminalises or restricts the dissemination of false or misleading information likely to cause public harm, particularly online. While often justified as necessary to combat disinformation, such laws risk enabling governments to dominate public discourse and suppress dissent. Although widely criticised for their chilling effect on freedom of expression, there is no consistent framework for assessing this impact across legal systems, especially beyond the Western context.
This study introduces the Chilling Effect Ranking (CER), a structured analytical tool grounded in legal scholarship and international human rights standards. Applying CER to seven East and Southeast Asian jurisdictions — China, Hong Kong, Taiwan, Singapore, Malaysia, Japan and South Korea — the paper identifies significant variation in the severity of chilling effects, ranging from high (e.g. Singapore, China) to moderate (e.g. Taiwan, Japan). The findings suggest that these effects stem not from the mere existence of such laws, but from flaws in their legal design. The CER offers practical guidance for policymakers aiming to regulate harmful content without eroding fundamental rights