bluuebunny/crossref_metadata_2025 huggingface dataset:
Fractional Derivative to Symmetrically Extend the Memory of Fuzzy C-Means
Authors: Safouan Safaa , El Moutaouakil Karim , Patriciu Alina-Mihaela
Published: October 2024

The fuzzy C-means (FCM) clustering algorithm is a widely used unsupervised learning method known for its ability to identify natural groupings within datasets. While effective in many cases, FCM faces challenges such as sensitivity to initial cluster assignments, slow convergence, and difficulty in handling non-linear and overlapping clusters. Aimed at these limitations, this paper introduces a novel fractional fuzzy C-means (Frac-FCM) algorithm, which incorporates fractional derivatives into the FCM framework. By capturing non-local dependencies and long memory effects, fractional derivatives offer a more flexible and precise representation of data relationships, making the method more suitable for complex datasets. Additionally, a genetic algorithm (GA) is employed to optimize a new least-squares objective function that emphasizes the geometric properties of clusters, particularly focusing on the Fukuyama–Sugeno and Xie–Beni indices, thereby enhancing the balance between cluster compactness and separation. Furthermore, the Frac-FCM algorithm is evaluated on several benchmark datasets, including Iris, Seed, and Statlog, and compared against traditional methods like K-means, SOM, GMM, and FCM. The results indicate that Frac-FCM consistently outperforms these methods in terms of the Silhouette and Dunn indices. For instance, Frac-FCM achieves higher Silhouette scores of most cases, indicating more distinct and well-separated clusters. Dunn’s index further shows that Frac-FCM generates clusters that are better separated, surpassing the performance of traditional methods. These findings highlight the robustness and superior clustering performance of Frac-FCM. The Friedman test was employed to enhance and validate the effectiveness of Frac-FCM.
Some Results for a Class of Pantograph Integro-Fractional Stochastic Differential Equations
Authors: Abusalim Sahar Mohammad , Fakhfakh Raouf , Alshahrani Fatimah , Ben Makhlouf Abdellatif
Published: October 2024

Symmetrical fractional differential equations have been explored through a variety of methods in recent years. In this paper, we analyze the existence and uniqueness of a class of pantograph integro-fractional stochastic differential equations (PIFSDEs) using the Banach fixed-point theorem (BFPT). Also, Gronwall inequality is used to demonstrate the Ulam–Hyers stability (UHS) of PIFSDEs. The results are illustrated by two examples.
Enhancing Adversarial Robustness through Stable Adversarial Training
Authors: Yan Kun , Yang Luyi , Yang Zhanpeng , Ren Wenjuan
Published: October 2024

Deep neural network models are vulnerable to attacks from adversarial methods, such as gradient attacks. Evening small perturbations can cause significant differences in their predictions. Adversarial training (AT) aims to improve the model’s adversarial robustness against gradient attacks by generating adversarial samples and optimizing the adversarial training objective function of the model. Existing methods mainly focus on improving robust accuracy, balancing natural and robust accuracy and suppressing robust overfitting. They rarely consider the AT problem from the characteristics of deep neural networks themselves, such as the stability properties under certain conditions. From a mathematical perspective, deep neural networks with stable training processes may have a better ability to suppress overfitting, as their training process is smoother and avoids sudden drops in performance. We provide a proof of the existence of Ulam stability for deep neural networks. Ulam stability not only determines the existence of the solution for an operator inequality, but it also provides an error bound between the exact and approximate solutions. The feature subspace of a deep neural network with Ulam stability can be accurately characterized and constrained by a function with special properties and a controlled error boundary constant. This restricted feature subspace leads to a more stable training process. Based on these properties, we propose an adversarial training framework called Ulam stability adversarial training (US-AT). This framework can incorporate different Ulam stability conditions and benchmark AT models, optimize the construction of the optimal feature subspace, and consistently improve the model’s robustness and training stability. US-AT is simple and easy to use, and it can be easily integrated with existing multi-class AT models, such as GradAlign and TRADES. Experimental results show that US-AT methods can consistently improve the robust accuracy and training stability of benchmark models.
Reliability Analysis for Degradation-Shock Processes with State-Varying Degradation Patterns Using Approximate Bayesian Computation (ABC) for Parameter Estimation
Authors: Muhammad Isyaku , Muhammad Mustapha , Wang Baohua , Chen Wang , Abba Badamasi , Usman Mustapha Mukhtar
Published: October 2024

The degradation of products is an integral part of their life-cycle, often following predictable trajectories. However, sudden, unexpected events, termed ’shocks’, can substantially alter these degradation paths. Shocks can significantly influence the pace of degradation, leading to accelerated system failure. Moreover, they may initiate changes in degradation patterns, transitioning from linear to non-linear or random trajectories. To address this challenge, we present a novel multi-state reliability model for competing failure processes that account for degradation-shock dependencies by considering the state-varying degradation pattern. The degradation process is divided into s-states, with each state treated according to its pattern based on the time-transform Wiener process. The reliability function is derived based on soft failure caused by continuous degradation involving the s-states, the sudden increase in degradation caused by random shocks, and hard failure due to some shock processes. Additionally, we performed a sensitivity analysis to determine which parameters have the most significant impact on product reliability. Due to the complexity of the likelihood function, we adopted the ABC method to estimate the model parameters. A simulation study and a practical application with micro-electro-mechanical systems (MEMS) degradation results are used to demonstrate the efficiency and effectiveness of the proposed approach.
Some Limiting Measures Related to Free and Boolean Convolutions
Authors: Alanzi Ayed. R. A. , Alshqaq Shokrya S. , Fakhfakh Raouf
Published: October 2024

Several authors are interested in the study of limiting distributions for large symmetrical random matrices. Our approach of studying limiting distributions is different and is related to the new concept of variance functions of Cauchy–Stieltjes Kernel (CSK) families of probabilities. By means of the variance functions machinery, some novel limiting probability measures are provided involving the free multiplicative law of large numbers, using both free and Boolean (additive and multiplicative) convolutions. Several examples of these limiting probability measures are given in the context of free probability.
Quaternion and Biquaternion Representations of Proper and Improper Transformations in Non-Cartesian Reference Systems
Authors: Katrusiak Andrzej , Le Hien Quy
Published: October 2024

Quaternion and biquaternion symmetry transformations have been applied to non-Cartesian reference systems of direct and reciprocal crystal lattices. The transformations performed directly in the sets of crystal reference axes simplify the calculations, eliminate the need for orthogonalization, permit the use of crystallographic vectors for defining the directions of rotations and perform the computations directly in the crystal coordinates. The applications of the general quaternion transformations are envisioned for physical, chemical, crystallographic and engineering applications. The general quaternion multiplication rules for any symmetry-unrestricted lattices have been derived for the triclinic crystallographic system and have been applied to the biquaternion representations of all point-group symmetry elements, including the crystallographic hexagonal system. Cayley multiplication matrices for point-groups, based on the biquaternion symbols of proper and improper symmetry elements, have been exemplified.
Language Styles, Recovery Strategies and Users’ Willingness to Forgive in Generative Artificial Intelligence Service Recovery: A Mixed Study
Authors: Lv Dong , Sun Rui , Zhu Qiuhua , Cheng Yue , Wang Rongrong , Qin Shukun
Published: October 2024

As the prevalence of generative artificial intelligence (GenAI) in the service sector continues to grow, the impact of the language style and recovery strategies utilized during service failures remains insufficiently explored. This study, grounded in the theory of social presence and dual-process theory, employed a mixed-method approach combining questionnaire surveys and event-related potential (ERP) experiments to investigate the effect of different language styles (rational vs. humorous) and recovery strategies (gratitude vs. apology) on users’ willingness to forgive during the GenAI service recovery process. It further delves into the chained mediating role of perceived sincerity and social presence in this process. The findings revealed that a humorous language style was more effective in enhancing users’ willingness to forgive compared to a rational style, primarily through the enhancement of users’ perceived sincerity and sense of social presence; recovery strategies played a moderating role in this process, with the positive impact of perceived sincerity on social presence being significantly amplified when the GenAI service adopted an apology strategy. ERP results indicated that a rational language style significantly induced a larger N2 component (cognitive conflict) in apology scenarios, while a humorous style exhibited higher amplitude in the LPP component (positive emotional evaluation). This research unveils the intricate relationships between language style, recovery strategies, and users’ willingness to forgive in the GenAI service recovery process, providing important theoretical foundations and practical guidance for designing more effective GenAI service recovery strategies, and offering new insights into developing more efficacious GenAI service recovery tactics.
Epidemiology and Ecology of Usutu Virus Infection and Its Global Risk Distribution
Authors: Chen Jiahao , Zhang Yuanyuan , Zhang Xiaoai , Zhang Meiqi , Yin Xiaohong , Zhang Lei , Peng Cong , Fu Bokang , Fang Liqun , Liu Wei
Published: October 2024

Usutu virus (USUV) is an emerging mosquito-transmitted flavivirus with increasing incidence of human infection and geographic expansion, thus posing a potential threat to public health. In this study, we established a comprehensive spatiotemporal database encompassing USUV infections in vectors, animals, and humans worldwide by an extensive literature search. Based on this database, we characterized the geographic distribution and epidemiological features of USUV infections. By employing boosted regression tree (BRT) models, we projected the distributions of three main vectors (Culex pipiens, Aedes albopictus, and Culiseta longiareolata) and three main hosts (Turdus merula, Passer domesticus, and Ardea cinerea) to obtain the mosquito index and bird index. These indices were further incorporated as predictors into the USUV infection models. Through an ensemble learning model, we achieved a decent model performance, with an area under the curve (AUC) of 0.992. The mosquito index contributed significantly, with relative contributions estimated at 25.51%. Our estimations revealed a potential exposure area for USUV spanning 1.80 million km2 globally with approximately 1.04 billion people at risk. This can guide future surveillance efforts for USUV infections, especially for countries located within high-risk areas and those that have not yet conducted surveillance activities.
Efficacy of Integrase Strand Transfer Inhibitors and the Capsid Inhibitor Lenacapavir against HIV-2, and Exploring the Effect of Raltegravir on the Activity of SARS-CoV-2
Authors: Kiarie Irene Wanjiru , Hoffka Gyula , Laporte Manon , Leyssen Pieter , Neyts Johan , Tőzsér József , Mahdi Mohamed
Published: October 2024

Retroviruses perpetuate their survival by incorporating a copy of their genome into the host cell, a critical step catalyzed by the virally encoded integrase. The viral capsid plays an important role during the viral life cycle, including nuclear importation in the case of lentiviruses and integration targeting events; hence, targeting the integrase and the viral capsid is a favorable therapeutic strategy. While integrase strand transfer inhibitors (INSTIs) are recommended as first-line regimens given their high efficacy and tolerability, lenacapavir is the first capsid inhibitor and the newest addition to the HIV treatment arsenal. These inhibitors are however designed for treatment of HIV-1 infection, and their efficacy against HIV-2 remains widely understudied and inconclusive, supported only by a few limited phenotypic susceptibility studies. We therefore carried out inhibition profiling of a panel of second-generation INSTIs and lenacapavir against HIV-2 in cell culture, utilizing pseudovirion inhibition profiling assays. Our results show that the tested INSTIs and lenacapavir exerted excellent efficacy against ROD-based HIV-2 integrase. We further evaluated the efficacy of raltegravir and other INSTIs against different variants of SARS-CoV-2; however, contrary to previous in silico findings, the inhibitors did not demonstrate significant antiviral activity.
Changes in Water Quality and Soil Property in the Rice–Freshwater Animal Co-Culturing System
Authors: Kaewpuangdee Phaiboon , Saowakoon Samnao , Kasamawut Krittima , Kruapukdee Ajcharawadee , Jutagate Achara , Jutagate Tuantong
Published: October 2024

This study investigated the effects of integrating various fish species in a rice field co-culture system on water quality and soil properties. The species included common carp (Cyprinus carpio), Nile tilapia (Oreochromis niloticus), silver barb (Barbonymus gonionotus), snakeskin gourami (Trichopodus pectoralis), and giant freshwater prawn (Macrobrachium rosenbergii). The key water quality parameters measured included water temperature, dissolved oxygen, pH, transparency, ammonia, and nitrite. Soil properties were evaluated through pH, electrical conductivity, organic matter, nitrogen, phosphorus, and potassium. All the selected aquatic animals showed high adaptability in co-culture systems, with survival rates exceeding 80%. Additionally, rice yields increased by approximately 16%, with the highest yield observed in plots stocked with prawns. The results indicated that the presence of aquatic animals enhanced nutrient cycling, leading to significant improvements in both water quality and soil fertility. Differences in water quality and soil properties throughout the culture period were specific to the species present. These findings suggest that rice-fish co-culture systems serve as an effective nature-based solution for enhancing productivity, sustainability, and food security.
Revealing Public Perceptions of Biodiverse vs. Turf Swales: Balancing Enhanced Ecosystem Services with Heightened Concerns
Authors: Wu Hong , Hoffman Margaret C. , Wang Rui , Kelley Kathleen M. , Adib Mahsa
Published: October 2024

Green stormwater infrastructure (GSI) is increasingly implemented worldwide to address stormwater issues while providing co-benefits such as habitat provision. However, research on public perceptions of GSI’s ecosystem benefits is limited, and barriers such as perception and maintenance hinder biodiversity promotion in GSI. Through an online survey (n = 781), we explored how residents in four Northeast US urban areas—Prince George’s County and Montgomery County, MD, New York City, and Philadelphia, PA—perceived the benefits and concerns regarding two types of bioswales (biodiverse and turf). Biodiverse swales feature various plants to promote biodiversity, whereas turf swales are primarily grass-covered. Our analyses included paired-samples t-tests, independent t-tests, one-way repeated measures ANOVA tests, and one-way ANOVA tests to compare perceptions across bioswale types, aspects of benefit/concern, and locations. Both bioswale types were recognized for enhancing green spaces and neighborhood aesthetics. Residents perceived greater environmental and social benefits from biodiverse swales than turf swales, particularly for habitat provision. While overall concerns for both bioswale types were low, potential issues like pest cultivation and the unappealing appearance of biodiverse swales remain significant barriers. Notably, implementing biodiverse swales alleviated initial concerns, especially about pests, suggesting familiarity can enhance acceptance. Location-specific differences in perception were observed, with New York City showing higher perceived benefits and concerns and Montgomery County exhibiting the lowest concerns. This variance is likely due to distinct urban environments, levels of environmental awareness, and demographic profiles.
Influence of Rainfall Patterns on Rainfall–Runoff Processes: Indices for the Quantification of Temporal Distribution of Rainfall
Authors: Oh Byunghwa , Kim JongChun , Hwang Seokhwan
Published: October 2024

To understand the influence of rainfall patterns on rainfall–runoff processes, we propose two indices: skewnessPEAK (skewp), representing the relative timing of peak rainfall, and the normalized root-mean-square error peak (NRMSEp), which quantifies the concentration of rainfall near the peak. By analyzing approximately 25,000 rainfall scenarios, we examined the relationship between these indices and peak flood discharge in the rainfall–runoff process. The analysis revealed that peak flood discharge positively correlates with the NRMSEp, indicating that concentrated rainfall near the peak substantially increases discharge. Conversely, a negative correlation with skewp suggests that earlier peak rainfall reduces discharge. These insights were synthesized into a three-dimensional solution space providing a comprehensive framework for predicting how variations in rainfall distribution affect flood discharge. The findings underscore the importance of incorporating these indices into real-time flood forecasting models and urban flood risk management strategies.
Pervasive Microplastic Ingestion by Commercial Fish Species from a Natural Lagoon Environment
Authors: Athukorala Ashini , Amarathunga A. A. D. , De Silva D. S. M. , Bakir A. , McGoran A. R. , Sivyer D. B. , Dias B. C. G. , Kanishka W. S. , Reeve C.
Published: October 2024

Microplastics have emerged as a significant global environmental concern in the recent decade. The aim of this study was to elucidate microplastic contamination of commercial fish species in a natural lagoon environment. Microplastic contamination was examined in the gastrointestinal tracts and gills of 157 commercial fish from 18 species with varying feeding habits in a vital and sensitive lagoon ecosystem, which connects to the Indian ocean. Microplastics were extracted using digestion, followed by stereomicroscopic inspection using Nile Red stain, and identified via μ-FTIR analysis. Over half of studied fishes ingested microplastics (54.14%). Filaments (50%) and blue items (43%) were the most commonly ingested. Of all the fish species, Eubleekeria splendens had the highest average concentration of microplastics in GIT (1.41 ± 2.52 items/g w.w. tissues), although no statistically significant difference in amount of ingested microplastics (items/g w.w. tissues) was observed among species. The highest concentrations of inhaled microplastics were recorded in Sillago vincenti (1.38 ± 1.30 items/g w.w. tissues). The majority of the extracted microplastics (33%) belonged in the size class 500–1500 μm with rayon, polyethylene terephthalate, and polypropylene as the primary polymers. This study found no correlation between microplastic ingestion and fish species and feeding habits, but a positive correlation with fish size was observed. These findings reveal widespread microplastic contamination in edible fish, posing potential risks to commercially important species due to increasing pollution in lagoon ecosystems.
Short-Term Effects of Abrupt Salinity Changes on Aquaculture Biofilter Performance and Microbial Communities
Authors: Costigan Eliza M. , Bouchard Deborah A. , Ishaq Suzanne L. , MacRae Jean D.
Published: October 2024

In recirculating aquaculture systems (RASs), ammonia excreted by fish must be converted to the less toxic nitrate before recirculation. Nitrifying microorganisms in biofilters used for this transformation can be sensitive to changes in salinity, which can present issues for systems that raise anadromous fish such as Atlantic salmon. Freshwater biofilters maintained at a low level of salinity (such as biofilters operated in coastal areas) may be better equipped to handle more drastic salinity shifts; therefore, experiments were performed on freshwater and low-salinity (3 ppt) biofilters to assess their ability to recover nitrification activity after an abrupt change in salinity (3, 20, and 33 ppt). Two-week tests showed full nitrification recovery in freshwater biofilters after a shift to 3 ppt but no ammonia oxidation in 20 or 33 ppt. Low-salinity-adapted filters (transitioned from 0 to 3 ppt) showed a small recovery (about 11%) after a shift to 20 ppt, and no activity when shifted to 33 ppt. Illumina sequencing revealed that, while nitrification was slowed or stopped with shifting salinities, the nitrifiers survived the salinity increases; conversely, the heterotrophic communities were more greatly affected and were reduced in proportion with increasing salinity. This work indicates that biofilters operated at low salinity may recover more quickly after large salinity changes, though this slight benefit may not outweigh the cost of low-level salinity maintenance. Further research into halotolerant heterotrophs in biofilms may increase the effectiveness of nitrifying biofilters under variable salinities.
Wetland Landscape Dynamics and Multi-Functional Assessment of Wuhan City, China
Authors: Yan Yuelin , Gan Xintao , Zhao Yajin , Liao Qipeng , Huang Chunbo
Published: October 2024

Under the dual pressures of rapid urbanization and intensifying global climate change, China has proposed governance policies aimed at promoting ecological urban construction. Wetland landscapes play a key role in sustaining human and social well-being. As a significant city in the middle reaches of the Yangtze River, Wuhan’s wetland resources play an irreplaceable role in maintaining the regional ecological balance and promoting sustainable economic and social development. However, urbanization poses a severe challenge to the ecological service functions of wetlands. Consequently, in this study, we analyzed the spatial–temporal evolution patterns of the sub-functional systems of carbon sequestration, biodiversity conservation, water yield, and water purification in five wetland types in Wuhan City from 2000 to 2020 by using the CASA model and InVEST model. Then, a wetland multi-functional assessment framework was constructed to quantify the comprehensive multi-function score. It is imperative to unravel the underlying mechanisms driving the changes in wetland functions and to explore the equilibrium point between wetland conservation and urban sustainable development. Our results show that the wetland area of Wuhan City decreased from 5077.33 km2 in 2000 to 4696.60 km2 in 2020, and the wetland multi-functions exhibited significant spatial heterogeneity from 2000 to 2020. Wetland carbon sequestration increased from 0.94 Tg in 2000 to 1.11 Tg in 2020. The wetland habitat quality declined from 0.13 in 2000 to 0.11 in 2020. The water production of the wetlands increased from 5.43 × 109 t in 2000 to 22.59 × 109 t in 2020. The wetland N loss decreased from 55,850.58 t in 2000 to 49,209.93 t in 2020. The highest multi-function score was in paddy fields, which increased from 0.41 ± 0.12 to 0.51 ± 0.12, followed by tidal flats, which increased from 0.39 ± 0.14 to 0.50 ± 0.16, and the lowest was rivers, which also increased from 0.33 ± 0.12 to 0.41 ± 0.14. The multi-function score was closely related to the wetland type and urban development direction over the past two decades, and it was negatively correlated with production and living density, providing new ideas for wetland ecological protection and construction in Wuhan City.
Chironomid Pupal Exuviae Technique in Ecological Research of Man-Made Water Bodies
Authors: Ergović Viktorija , Čerba Dubravka , Vučković Natalija , Mihaljević Zlatko
Published: October 2024

Reservoirs serve functional purposes such as irrigation and power generation. However, concerns are raised due to the alterations of the connected riverine ecosystems. Chironomidae (Diptera), a diverse aquatic macroinvertebrate group, are vital to the functioning of ecosystems and serve as water quality indicators. Their holometabolous development includes the pupal stage after four larval stages. The chironomid pupal skin (exuvia) is used in environmental assessments, where the Chironomid Pupal Exuvial Technique (CPET) is a recognized standard. The CPET method is adaptable to different freshwater environments and here was applied in the study of 28 man-made lakes in the Pannonian Lowlands and Dinaric Western Balkan Ecoregion in Croatia to obtain information on chironomid diversity and analyze the potential influence of environmental factors on the chironomid community. The lake surface was skimmed with an exuvial hand net (mesh size of 300 µm) along the lake edge with a transect length of 10 m in the area of accumulated debris of organic and inorganic matter. Individual exuviae were mounted in a Berlese mounting medium and identified by morphological characteristics to the lowest taxonomic level. During the study, 5698 chironomid pupal skins were collected, and 141 taxa (including 97 species) belonging to five subfamilies were identified. The tribe Tanytarsini comprised 40% of the identified taxa, with Paratanytarsus spp. being the most abundant. In the Dinaric ecoregion, Paratanytarsus bituberculatus dominated, while Microchironomus tener and the genus Cricotopus were the dominant taxa in the Pannonian ecoregion. Community structure in the Pannonian ecoregion was influenced by total organic carbon (TOC) and orthophosphates (PO43−), indicating higher anthropogenic pressure compared to the Dinaric ecoregion, where water conductivity influenced Chironomidae assemblages. The research has provided valuable and useful information on the chironomid diversity in man-made and highly altered water bodies, as some of the most vulnerable aquatic habitats to anthropogenic influence. The CPET method could be a useful tool for the ecological studies and bioassessment of water quality in Croatia.
Analysis of the Response of Shallow Groundwater Levels to Precipitation Based on Different Wavelet Scales—A Case Study of the Datong Basin, Shanxi
Authors: Zhang Hongyue , Rui Xiaoping , Zhou Ye , Sun Wen , Xie Weiyi , Gao Chaojie , Ren Yingchao
Published: October 2024

The rise in shallow groundwater levels is typically triggered by precipitation recharge, exhibiting a certain lag relative to precipitation changes. Therefore, identifying the response mechanism of shallow groundwater levels to precipitation is crucial for clarifying the interaction between precipitation and groundwater. However, the response mechanism of groundwater levels to precipitation is complex and variable, influenced by various hydrogeological and geographical conditions, and often exhibits significant nonlinear characteristics. To address this issue, this study employs methods such as continuous wavelet transform, cross wavelet transform, and wavelet coherence to analyze the response patterns of groundwater levels to precipitation at different wavelet scales in the Datong Basin from 2013 to 2022: (i) At short wavelet scales (10.33~61.96 d), the groundwater level dynamics respond almost instantaneously to extreme rainfall; (ii) At medium wavelet scales(61.96~247.83 d), the precipitation-groundwater recharge process shows characteristics of either rapid recovery or significant delay; (iii) At long wavelet scales (247.83~495.67 d), three potential groundwater processes were identified in the Datong Basin, exhibiting long-term lag responses throughout this study period, with lag times of 11.18 days, 148.75 days, and 151.49 days, respectively. Furthermore, the results indicate that the lag response time of shallow groundwater levels to precipitation is not only related to the wavelet scale but also to the identified depth conditions of different groundwater regions, groundwater extraction intensity, precipitation intensity, and aquifer lithology. This study distinguishes the temporal and spatial response mechanisms of shallow groundwater to precipitation at different wavelet scales, and this information may further aid in understanding the interaction between precipitation and groundwater levels.
Исследование воспламеняющей способности фрикционных искр
Authors: Трояк Е.Ю. , Пожаркова И.Н. , Богданов А.А.
Published: October 2024

В статье рассмотрены основные теоретические положения в области воспламеняющей способности фрикционных искр, выявлена и обобщена информация по результатам исследований, ученных в вышеуказанной области. Рассмотрена конструкция лабораторной установки для исследования воспламеняющей способности фрикционных искр, дана характеристика ее основных узлов. Описана методика проведения натурного эксперимента по определению воспламеняющей способности искр, а также указаны основные свойства горючих материалов, использующихся в эксперименте. Приведены результаты экспериментов по исследованию воспламеняющей способности фрикционных искр. Проведены расчеты конечной температуры и количества тепла, отдаваемой искрой. Выявлена зависимость времени зажигания горючих веществ и материалов от расстояния до источника образования фрикционных искр. Доказано, что, исходя из полученных данных, зависимость времени воспламенения исследуемых веществ и материалов от расстояния до источника образования фрикционных искр (в условиях эксперимента) носит линейный характер. Определено, что большее влияние на результаты воспламенения легковоспламеняющихся жидкостей оказывает не температура вспышки, а температура кипения жидкости, что приводит к более интенсивному его испарению и образованию концентрации паров над поверхностью, превышающей нижний концентрационный предел распространения пламени.

The article discusses the main theoretical principles in the field of the igniting ability of friction sparks, identifies and summarizes information based on the results of research by scientists in the above area. The design of a laboratory installation for studying the flammable ability of friction sparks is considered, and the characteristics of its main components are given. The technique of conducting a full-scale experiment to determine the flammable ability of sparks is described, and the main properties of combustible materials used in the experiment are indicated. The results of experiments on the study of the flammable ability of friction sparks are presented. Calculations of the final temperature and the amount of heat given off by the spark are carried out. The dependence of the ignition time of combustible substances and materials on the distance to the source of the formation of friction sparks has been revealed. It is proved that, based on the data obtained, the dependence of the ignition time of the studied substances and materials on the distance to the source of the formation of friction sparks (under experimental conditions) is linear. It is determined that the greater influence on the results of ignition of flammable liquids is exerted not by the flash point, but by the boiling point of the liquid, which leads to its more intense evaporation and the formation of a vapor concentration above the surface exceeding the lower concentration limit of flame propagation.
Оценка эффективности тушения горючих жидкостей пеной совместно с хладоном
Authors: Гапеев А.А. , Гудков М.А. , Комраков П.В. , Мещеряков А.В. , Коваль Ю.Н.
Published: October 2024

В статье рассмотрены способы повышения эффективности огнетушащих пен, путем инжектирования в раствор пенообразователя хладонов, на примере хладона 318Ц и пенообразователя «Эльфор Джой». В модельном очаге пожара проведено экспериментальное сравнение подслойного и поверхностного способов тушения такими пенами. Определены численные значения критических и оптимальных параметров тушения для поверхностного и подслойного способов тушения. Дана оценка эффективности использования таких пен с помощью параметра эффективности тушения.

The article discusses ways to increase the efficiency of fire extinguishing foams by injecting freons into the solution of a foaming agent, using the example of freon 318C and the Elfor Joy foaming agent. In a model fire, an experimental comparison of sublayer and surface extinguishing methods with such foams was carried out. Numerical values of critical and optimal extinguishing parameters for surface and sublayer extinguishing methods have been determined. The effectiveness of using such foams is assessed using the extinguishing efficiency parameter.
Научные основы поиска технических решений дальних водяных струй
Authors: Амельчугов С.П. , Батуро А.Н. , Мартинович Н.В. , Коваль Ю.Н.
Published: October 2024

В статье рассмотрена проблема подачи воды на пожарах компактными струями. Дальность подачи воды пожарным стволом является ключевым фактором при тушении крупных пожаров, а также пожаров с высокой интенсивностью теплового излучения и возможными взрывами. В таких условиях важно обеспечить максимальную эффективность и дальность подачи воды и тем самым безопасность работы пожарных. Предложен новый способ расчета технических характеристик насадка пожарного ствола, позволяющий улучшить параметры подачи воды. Приведены результаты экспериментов, которые подтверждают эффективность предложенного метода. Для повышения дальности полета струи из насадка пожарного ствола его необходимо проектировать с таким условием, чтобы число Рейнольдса по длине насадка изменялось равномерно. Экспериментально установлена оптимальная длинна конической части насадка для обеспечения максимальной дальности струи. Установлено, что для стволов с большим расходом, необходимо многослойное внутреннее тело. Предложено решение в виде насадка представляющего из себя конфузор с внутренними конфузорами расчетного профиля по сечению.

The article addresses the issue of water delivery during firefighting operations using compact jets. The range of water delivery from a fire hose is a key factor in extinguishing large fires, as well as in situations involving high thermal radiation intensity and potential explosions. Under such conditions, it is crucial to ensure maximum efficiency in water delivery, thereby enhancing the safety of firefighting personnel. A novel method for calculating the technical characteristics of fire hose nozzles is proposed, which allows for the improvement of water delivery parameters. Experimental results confirming the effectiveness of the proposed method are presented. To increase the range of the jet from the fire hose nozzle, it is necessary to design the nozzle such that the Reynolds number changes uniformly along its length. The optimal length of the conical section of the nozzle for achieving maximum jet range has been experimentally established. It has been determined that for nozzles with a high flow rate, a multi-layered internal body is required. A solution is proposed in the form of a nozzle that consists of a diffuser with internal diffusers designed with a calculated cross-sectional profile.
Прогнозирование пожароопасных свойств сжиженного природного газа с использованием симплекс–решетчатых планов Шеффе
Authors: Гудков М.А. , Гапеев А.А. , Тетерин А.А. , Коваль Ю.Н. , Герасименко Е.С.
Published: October 2024

Настоящая работа посвящена проблеме обеспечения пожарной безопасности на объектах хранения, транспортировки и потребления сжиженного природного газа (СПГ). Так как основной характеристикой природного газа в качестве топлива является его энергетическая ценность, то оценка пожаровзрывоопасных свойств должна выполняться с учетом энергетического показателя. В качестве пожароопасных свойств рассмотрены избыточное давление взрыва и концентрационные пределы распространения пламени, а в качестве энергетического – число Воббе. Данные характеристики зависят от состава СПГ, который может меняться в пределах основных горючих компонентов: метан, этан, пропан, бутан. В этой связи, практический интерес представляет собой получение зависимостей, которые позволяют находить наиболее оптимальные свойства в зависимости от состава. Для решения поставленной задачи использовался метод оптимизации эксперимента симплекс-решетчатый план Шеффе третьего порядка с центральной точкой. Для его использования был упрощен состав, что обоснованно процентным содержанием основных горючих компонентов и их вкладом в исследуемые показатели. В результате получена система уравнений, позволяющая прогнозировать энергетические и пожароопасные свойства СПГ в зависимости от состава. Показан пример расчета.

This work is devoted to the problem of ensuring fire safety at facilities for storing, transporting and consuming liquefied natural gas (LNG). Since the main characteristic of natural gas as a fuel is its energy value, the assessment of fire and explosion hazard properties must be carried out taking into account the energy indicator. Excessive explosion pressure and concentration limits of flame propagation are considered as fire hazardous properties, and the Wobbe number is considered as energy properties. These characteristics depend on the composition of LNG, which can vary within the main combustible components: methane, ethane, propane, butane. In this regard, it is of practical interest to obtain dependencies that allow one to find the most optimal properties depending on the composition. To solve the problem, the experiment optimization method was a simplex-lattice Scheffé design of the third order with a central point. For its use, the composition was simplified, which is justified by the percentage content of the main combustible components and their contribution to the studied indicators. As a result, a system of equations was obtained that allows one to predict the properties of LNG depending on the composition. An example calculation is shown.
Разработка критериев и алгоритма проведения оценки управления планирования занятий по разбору пожаров
Authors: Михайлин П.О.
Published: October 2024

подготовка профессиональных пожарных является неотъемлемой частью деятельности пожарной охраны. В данной статье проведен анализ сведений, представленных территориальными органами МЧС России по субъектам Российской Федерации в части, касающейся произошедших пожаров на разных категориях объектов. Выдвинута гипотеза, что количество исследуемых пожаров лицами, принимающими решение на пожаре, оказывает влияние на параметрические показатели пожара ( ). По мимо гипотезы предложены критерии оценки оптимального количества проведенных занятий по разбору пожара и исследуемых пожаров в подразделениях пожарной охраны, а также предложен алгоритм определения количества исследуемых пожаров из большого массива данных, основанный на одной из математических теорий, позволяющий определить достаточность управленческого воздействия на процесс планирования занятий по профессиональной подготовке должностных подразделений пожарной охраны в пожарно-спасательном гарнизоне.

training of professional firefighters is an integral part of the activities of the fire department. This article analyzes the information provided by the territorial bodies of the Ministry of Emergency Situations of Russia for the constituent entities of the Russian Federation in terms of fires that occurred at different categories of objects. It is hypothesized that the number of fires studied by fire decision makers influences the fire parametric indicators (S_fire). In addition to the hypothesis, criteria for assessing the optimal number of fire analysis classes and fires under study in fire departments are proposed, and an algorithm is proposed for determining the number of fires under study from a large array of data, based on one of the mathematical theories, allowing to determine the sufficiency of management influence on the lesson planning process on professional training of fire departments in the fire and rescue garrison.
PRESENÇA DE PARASITOS DA ORDEM STRONGYLIDA EM BOVINOS LEITEIROS CRIADOS A PASTO E EM SISTEMA COMPOST BARN NA MICRORREGIÃO DE FREDERICO WESTPHALEN
Authors: Heineck Isabel Cristina , Migliorini Kelly , Tiaraju Goral de Paula Miguel , Manfro Magalhães Gabriela , Grando Thirssa Helena , Bandeira Junior Guerino
Published: October 2024

A presença constante de endoparasitos em rebanhos leiteiros tem afetado a produtividade e o bem estar dos animais. Com isso, a utilização do exame de fezes tem se tornado crucial para médicos veterinários e donos de propriedades, uma vez que os resultados obtidos permitem a adoção de medidas de controle e prevenção cabíveis. Há uma escassez de trabalhos que relacionam os sistemas de criação com o nível de parasitismo em bovinos. Neste trabalho, foram visitadas 12 propriedades na microrregião de Frederico Westphalen - RS, sendo 6 delas em sistema extensivo a pasto e as outras 6 propriedades em sistema intensivo (compost barn). Por meio da análise de fezes nessas propriedades, constatou-se o que já era esperado, que em sistemas a pasto, os animais estão mais suscetíveis a helmintoses. Tanto sistemas intensivos quanto extensivos da pecuária leiteira apresentaram endoparasitoses, mostrando que mesmo bovinos criados em manejo intensivos estão expostos aos parasitos gastrointestinais. Conclui-se que no sistema intensivo, como o compost barn, o produtor detém um controle maior de parasitos que possam eventualmente acometer o rebanho, porém não anula a possibilidade de ocorrerem infecções nos animais.
DOMA RACIONAL DE CAVALOS
Authors: Do Rego Vasconcelos Luís Eduardo , Da Silva Barbosa Cristiane , De França Oliveira da Silva Mariana , Borba Leite Ana Greice
Published: October 2024

A relação humanos e cavalos iniciou a milhares de anos na condição de predador e presa. Na domesticação, nem sempre houve a preocupação com o bem-estar dos animais, ao contrário da doma racional, que utiliza comunicação e linguagem corporal. Esse estudo foi realizado no centro de treinamento de cavalos em Limoeiro, PE. A pesquisa foi realizada com o domador do centro, que relatou a metodologia empregada na doma racional dos animais, destacando as técnicas de reforçamento negativo e aproximação sucessiva. A doma dos potros é iniciada após o nascimento, realizando a dessensibilização e implementação do cabresto. A partir do sétimo dia, os animais começam a responder aos comandos de voz e cabresto, dando início os flexionamentos. Quando os potros assimilam o que é proposto, por volta do 15º dia, eles são induzidos a recuar. Com o cavalo adulto, a primeira atividade é no redondel e realizar a conjunção. Desse modo, ganha-se a confiança do animal e o domador consegue estabelecer uma relação de liderança. Depois é iniciado o processo de dessensibilização com cordas e/ou bandeiras, com o intuito de diminuir o extinto de fuga e mostrar sempre que é perto dos humanos o lugar mais seguro. Para doma racional é preciso observar o comportamento do cavalo, se conectar ao animal é o melhor caminho para fazê-lo se sentir seguro, confortável e dê o seu melhor.
التحليل المكاني للغطاء الأرضي واستعمالات الأراضي في لواء الشوبك1/محافظة معان، خلال الفترة 1990-2021 باستخدام الاستشعار عن بعد ونظم المعلومات الجغرافية
Authors: Zregat Dalal
Published: October 2024

تهدف هذه الدراسة إلى تحديد الأنواع الرئيسة للغطاء الأرضي واستعمالات الأراضي في لواء الشوبك/ محافظة معان، وتحليل معدل التغيّر المكانيّ والزمنيّ لتوزيع الغطاء الأرضي واستعمالات الأراضي، بالاعتماد على نظم المعلومات الجغرافيّة (GIS)، وتقنيات الاستشعار عن بعد (RS)، وقد تم اشتقاق الخصائص الطبوغرافيّة المختلفة من خلال نموذج الارتفاعات الرقمية Digital Elevation Model (DEM)، المشتق من الخرائط الطبوغرافيّة للواء الشوبك، مقياس 1:25000، كما تم استخدام الصور الفضائية Landsat للأعوام 1990 و2005 و2021م. توصلت الدراسة إلى أنّ هناك أربعة أنواع رئيسة للغطاء الأرضي واستعمالات الأراضي في لواء الشوبك وهي: الأراضي المبنيّة، والأراضي الزراعية، والأراضي الجرداء، والأراضي غير المستغلة. وقد توصلت الدّراسة أيضًا إلى أنّ هناك تغيّرًا في الغطاء الأرضي واستعمالات الأراضي خلال الفترة 1990-2021؛ إذ بلغ معدل التغيّر في الأراضي المبنيّة 200%، والأراضي الزراعية -84.14%، والأراضي غير المستغلة 10.3%، والأراضي الجرداء 0.21%، كما بينّت الدراسة التّحوّل لكلّ نوع من أنواع الغطاء الأرضي واستعمالات الأراضي.
Criminal Thinking Patterns of Inmates in Light of Some Personal Variables: A Field Study on a Sample of Inmates of the Swaqa Correctional and Rehabilitation Center
Authors: Aljbour Rami Abed AL-Hameed , AL-Wraikat Ayed Awad
Published: October 2024

The study aims to identify the nature of criminal thinking patterns among inmates in light of certain personal variables by conducting a field study on a sample of inmates at the Swaqa Rehabilitation and Correctional Center. To achieve the study's objectives, the descriptive-analytical method was used, employing a questionnaire as the study tool. The study sample consisted of 223 inmates selected through a non-probability convenience sampling method. The results showed that the criminal thinking pattern of "blaming others" had a high degree, with a mean score of 3.69. In contrast, the criminal thinking patterns of "non-interaction with others" (antisocial) and "closed mindedness" (rigidity in opinion) were moderate, with mean scores of 3.08 and 3.29, respectively. The results also revealed statistically significant differences in criminal thinking patterns based on variables such as age, family monthly income, life satisfaction, and the number of crimes committed. Based on these findings, the study recommended reconsidering and developing rehabilitation programs to help modify criminal thinking patterns among inmates.
La movilidad de estudiantes de grado del Mercosur en el contexto de la internacionalización de la educación superior pública
Authors:   , Ferrari Hugo Domingo
Published: October 2024

Esta tesis tiene como objetivo examinar las características de los programas de movilidad de estudiantes de grado de universidades públicas en el marco del Sector Educativo del MERCOSUR (SEM). En esta investigación se llevó a cabo un proceso mixto o multimodal. A través de este se recolectaron, vincularon y analizaron datos cuantitativos y cualitativos. La población estuvo constituida por estudiantes de la carrera de Abogacía de la Universidad Nacional del Noroeste de la Provincia de Buenos Aires (UNNOBA) y de la Universidad Nacional de La Plata (UNLP), como también por dos especialistas en educación superior. Los instrumentos empleados fueron cuestionarios aplicados a los educandos, entrevistas a los profesionales en la materia y documentación alusiva. Con los resultados obtenidos quedaría establecido en esta tesis que tales políticas universitarias no existirían aún en cantidad y calidad suficientes para favorecer la convergencia de la educación universitaria pública e impulsar el proceso de integración subregional.