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Experimental Characterization of Materials for Structural Airframe Elements of a Multirotor UAV
No full textThis work presents a cost-efficient experimental framework for characterizing structural materials used in rotor arms of multirotor UAVs. A set of specimens, in-cluding FDM-printed PLA and PETG with varying wall thicknesses and infill percentages, and CFF-printed Onyx reinforced with fiberglass, was evaluated against a commercially established reference (S500). Static deflection tests revealed that increasing the wall number and infill in PETG specimens reduces deflection at the expense of mass, with the selected PETG design achieving ~30 % lower de-flection and ~20 % lower mass than the commercial airframe. CFF specimens showed superior stiffness but were considerably more expensive and required sig-nificantly longer production times. The study demonstrates that low-cost experimental testing provides useful mechanical data, supporting the design of lighter, structurally efficient rotor arms
Second Home Tourism and Crisis Communication: Communication Preferences and Risk Awareness in Sweden
No full textCrisis is an inherent feature of contemporary societies; hence, risk awareness and crisis preparedness have become important in planning strategies. A crucial component that has emerged is the need for crisis communication and investigations to promote and involve communication by various local groups. One such group is second-home tourists, who are commonly well-integrated socially into local communities in the Nordic countries. However, the knowledge and inclusion of second-home tourists in planning strategies, including risk preparedness, requires improvement in local jurisdictions. Second-home communities are diverse, implying that efficient crisis communication needs to account for the place-specific characteristics of these temporary population groups. This short communication presents results from a survey on crisis-communication preferences and behaviour among second-home owners in Sweden. We explore how second-home owners communicate from their second home, to what extent they are aware of risks, and how they view the role of communication in a potential crisis
Effect sizes for nonparametric tests
No full textEffect size measures are important complements to P values, providing information about the magnitude and practical relevance of research findings. While widely discussed in the context of parametric tests, effect size estimation for nonparametric tests remains less explored. This article reviews standardized effect size measures applicable to four common nonparametric tests: Mann-Whitney, Wilcoxon signed-rank, Kruskal-Wallis, and Friedman. Commonly suggested classifications for these effect sizes are also discussed. This article aims to support researchers in reporting and interpreting effect sizes more effectively in nonparametric contexts
Key incidents identified by the Royal College of Pathologists of Australasia Quality Assurance Programs Key Incident Monitoring and Management EQA program
No full textIntroduction: The Royal College of Pathologists of Australasia Quality Assurance Programs (RCPAQAP) Key Incident Monitoring and Management EQA Program (KIMMS) aims to monitor the laboratory quality system’s pre- and post-analytical phases. The purpose of this paper is to describe the most common incidents from 2024.
Materials and methods: The KIMMS program has four surveys a year, collecting data from the previous three months, with preanalytical and postanalytical incident reporting of 35 incident types. Participants are asked to capture the number of episodes and the number of incidents per quarter of the year.
Results: The four 2024 surveys received an average of 111 responses, with 55,329,998 episodes recorded and 1,496,708 incidents identified. The findings from the 2024 program are that the incident “No specimen received” appears to have the highest 80th percentile across the patient sources. The commonest site of error is the Emergency Department (ED), with an 80th percentile overall.
Conclusions: The KIMMS data provide valuable, regular and reproducible benchmarking data for the pre- and post-analytical phases of the total testing cycle
A Video Summarization Technique using Multi- Feature DWHT and GMM for CBVR System
No full textThe increasing utilization of multimedia data and digital information in present times presents a vast scope for research in content-based retrieval systems. An improved CBVR System is proposed to extract video streams effectively using DWHT Multi- features and GMM. Our CVBR method performs VSBD for identifying Video shots by computing DWHT on video frames for multi- feature extraction, and then key frames are identified. A summarized frame is developed using the VS algorithm based on GMM on the UCF Dataset. Later, a procedure is applied for the input query video stream, and correlation coefficients are calculated between the query and the database multi-feature vectors, giving us similarity measures. Lastly, our experimental results validate the efficiency of our proposed CBVR System, achieving an average precision of 0.821 and a loss of 0.179, outperforming existing CBVR systems using DCT and optimized perceptual VS, which have precision values of 0.6475 and 0.71, respectively, along with losses of 0.3525 and 0.29
MPPSO-Based Collaborative Optimization for Emergency Medical Supplies Loading and Scheduling
No full textPublic emergency occurs frequently, which has a serious impact on people's life safety and social stability. When public emergency occurs, the government needs to respond quickly to reduce casualties and property losses. Emergency medical supplies scheduling is the key work of government response, which is a scheduling problem. To solve the scheduling problem, firstly, we designed a collaborative system of loading and scheduling of emergency medical supplies. Secondly, considering the waiting time and the affected level of the affected point, and the conflict time of loading and unloading, a loading and scheduling collaborative optimization model of emergency medical supplies is constructed, the objective of which is the minimum maximum weighted time of all affected points. Thirdly, based on the Multi-phase Particle Swarm Optimization (MPPSO), an improved Multi-phase Particle Swarm Optimization (IMPPSO) is designed to improve the ability to solve the constructed collaborative optimization model. Finally, by taking the rainstorm event in Fangshan District on July 31, 2023 as an example, the proposed method has obtained an efficient scheduling solution in a reasonable time. The average fitness obtained by IMPPSO is 15,58% and 42,95% better than that of MPPSO and Particle Swarm Optimization (PSO), respectively. It is proved that the proposed method has good feasibility in practical application, which provides emergency medical supplies scheduling decision support for emergency management departments in public emergency
Advanced Decision-Making with Interval-Valued Probabilistic Linguistic Fuzzy Sets
No full textDecision-making under uncertainty is a fundamental challenge in various fields, requiring methods that effectively capture probabilistic uncertainty and decision-maker hesitancy. This study introduces Interval-Valued Probabilistic Uncertain Linguistic q-Rung Orthopair Fuzzy Sets (IVPULq-ROFSs), a novel framework that extends existing fuzzy set models by incorporating interval-valued probabilities and linguistic hesitancy. Based on this model, we develop two advanced Multi-Attribute Group Decision-Making (MAGDM) methods: (1) an aggregation-based approach, and (2) a TODIM-based decision method. To validate the effectiveness of the proposed methods, we apply them to autonomous vehicle sensor configuration selection, demonstrating enhanced decision robustness and reliability. The results indicate that IVPULq-ROFSs outperform conventional fuzzy models in handling complex and uncertain decision scenarios. Future research will explore algorithmic optimization, real-time applications, and integration with deep learning models for enhanced decision intelligence
The Role of the Institutional Support Allocation System in Enhancing Scientific and Artistic Productivity at the University North
No full textThe system for awarding scientific and artistic grants at the University North serves as a key strategic instrument for advancing research and artistic productivity while strengthening the University's institutional recognition. By applying clearly defined criteria, transparent procedures, and comprehensive professional support provided by the Department for Scientific, Artistic Work and International Cooperation, the system ensures the efficient allocation of financial resources to researchers and teams whose projects demonstrate substantial scientific and societal value. An analysis of data from 2020-2024 reveals a consistent increase in the number of papers published in journals indexed in the Web of Science (WoS) and Scopus databases, with technical sciences, biomedicine, and social sciences emerging as the most productive disciplines. The grant system promotes interdisciplinary collaboration, the development of research teams, and the dissemination of findings through international databases, thereby fostering a culture of scientific excellence and open science.These findings confirm that institutional grants represent far more than a financial mechanism, they constitute a long-term investment in knowledge creation, innovation, and international competitiveness. At the same time, they enhance the scientific visibility and reputation of the University North at both national and international levels
A Novel Power Quality Improved Lead Acid Battery Charging System for the Electric Rickshaw
No full textSeveral thousands of electric rickshaws have been deployed in many of the Indian cities and the number of electric rickshaws deployed in various cities is growing day by day. The electric rickshaws invariably use 2 numbers of 12 V lead acid batteries. Most of the electric rickshaws commonly called E Rickshaws use domestic charging arrangements for charging the batteries and a variety of battery chargers is available in the market. This scenario has caused a great concern for the grid side power quality due to the nonlinear nature of the commercially available battery chargers which use rectifiers and filter capacitors. In this work a power factor corrected battery charging rectifier conforming to the charging pattern requirements of the lead acid batteries is presented. The control scheme ensures that the source current is of sinusoidal waveform. The proposed system uses a hysteresis controller and a sliding mode controller combination. The mathematical overheads and memory requirements in digital implementation of controller are minimal. The results of simulations carried out in the MATLAB SIMULINK environment and the results of the experimental prototype confirm and validate the efficacy of the proposed idea