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An Improved Attention-Enhanced LSTM Model for Early Detection of Distributed Denial of Service Attacks
No full texthttps://doi.org/10.1007/978-3-031-89518-0_
Buyer Platform Experience (PLX) in Online Marketplaces: Scale Development, Validation, and the Salience of Variety, Competitive Pricing, Service Excellence, and Promotion
No full textThis study aims to develop and validate a Buyer Platform Experience (PLX) scale focused on the cognitive and relational dimensions of buyer experience in online marketplaces. Adopting a five-stage sequential scale-development methodology, the research combines qualitative interviews with quantitative analyses using SPSS and AMOS. A four-dimensional scale—variety, service excellence, competitive pricing, and promotional effectiveness—was validated through exploratory and confirmatory factor analyses. Structural equation modeling confirmed that variety, service excellence, and competitive pricing significantly predict customer loyalty. The findings isolate cognitive and relational aspects often overlooked in existing customer-experience frameworks and offer practical guidance for platform managers seeking to enhance buyer retention through service quality, price competitiveness, and variety management.https://doi.org/10.1177/21582440251394446https://doi.org/10.2139/ssrn.5771323http://hdl.handle.net/20.500.12566/237
Comparative Assessment of Neural Radiance Fields and 3D Gaussian Splatting for Point Cloud Generation from UAV Imagery
No full textPoint clouds continue to be the main data source in 3D modeling studies with unmanned aerial vehicle (UAV) images. Structure-from-Motion (SfM) and MultiView Stereo (MVS) have high time costs for point cloud generation, especially in large data sets. For this reason, state-of-the-art methods such as Neural Radiance Fields (NeRF) and 3D Gaussian Splatting (3DGS) have emerged as powerful alternatives for point cloud generation. This paper explores the performance of NeRF and 3DGS methods in generating point clouds from UAV images. For this purpose, the Nerfacto, Instant-NGP, and Splatfacto methods developed in the Nerfstudio framework were used. The obtained point clouds were evaluated by taking the point cloud produced with the photogrammetric method as reference. In this study, the effects of image size and iteration number on the performance of the algorithms were investigated in two different study areas. According to the results, Splatfacto demonstrates promising capabilities in addressing challenges related to scene complexity, rendering efficiency, and accuracy in UAV imagery.https://doi.org/10.3390/s25102995http://dx.doi.org/10.3390/s25102995https://doaj.org/article/cec5d81391bf40e9bd5111b3a12553f
A Strategic Roadmap to Circularization of the Turkish Textile and Ready‐To‐Wear Industry Within the Context of the European Green Deal
No full textABSTRACT The European Green Deal (EGD), introduced in 2019, aims to achieve net‐zero greenhouse gas emissions by 2050. The mandate to transition to a circular economy (CE) across the supply chain constitutes a major pillar of EGD. This shift impacts both EU member states and countries exporting to the EU. The textile and ready‐to‐wear sector, known for its significant environmental footprint, has been identified as a priority industry requiring urgent reforms. Against this background, this paper assesses the key barriers to CE transition for Türkiye's textile industry and proposes a structured and validated roadmap. Key barriers to circularization, identified through a Fuzzy Cognitive Maps (FCM) method, include lack of awareness, short‐term priorities, limited management support, inadequate culture, low demand for circular products, and ineffective legislation. In‐depth expert interviews validated and provided additional insights on the barriers and their interlinkages from the FCM analysis, as well as the action items for the roadmap corresponding to barriers and their time horizons. The study underscores the need to plan collaborative actions of stakeholders in line with the 9 political patterns in the EU Circular Economy Action Plan, to align the Turkish textile and ready‐to‐wear industry with the EGD objectives, while protecting its competitiveness in global markets.https://doi.org/10.1002/bsd2.7015
Quantitative measurement of vapor concentration distribution for two-phase water flow in microchannels
No full textCavitation in the microchannel can affect the flow characteristics and cause corrosion damage to the microchannel. Quantitative vapor concentration characteristics inside the microchannel are a prerequisite for understanding the cavitation characteristics in microfluidics and cavitation simulation prediction. In this paper, high-speed visible-light imaging at the nanosecond timescale and micrometer spatial scale was used to study the vapor concentration in microchannels. The steady-state image was discretized from sub-millisecond scale (200 μs) to nanosecond scale images (20 ns) based on the equivalent same exposure time. The occurrence probabilities of the vapor and liquid phases at each pixel position can be calculated by means of proper segmentation of the vapor and liquid phases in the nanosecond cavitation images. The quantitative measurement of vapor-phase concentration in steady-state flow in a microfluidic channel was successfully realized with the accumulation of vapor-phase probability of nanosecond images. Vapor-phase concentrations of 0–100% can be effectively distinguished by this method, and the mixed flow characteristics of two cavitations can be quantified. In addition, the cavitation concentration mapped from the steady-state grayscale image was compared with the results of quantitative concentration measurements.https://doi.org/10.1063/5.027544
Evaluation on fire incident of electric vehicle spaces onboard ferries with using fire dynamics simulations
No full textThis study brings a unique perspective of electric vehicles (EVs) transportation via maritime with using performance-based design of fire safety management. In the recent years, due to the increase of production and transportation of EVs, this study is highlighted the fire safety management. The integration of electric vehicles (EVs) into maritime transport, particularly via ships and ferries, brings about unique challenges, notably concerning fire safety management. Given the increasing prevalence of EVs and their potential fire hazards, it’s crucial to address these risks comprehensively. The fire safety management of electric vehicles in ferry transport is dealt with, as this form of maritime transport is becoming increasingly important due to the increased production of this type of vehicle, which develops a complex chemical reaction mechanism and dangerous properties such as initial exothermal temperature, self-heating speed, pressure increase speed, etc. Therefore, relevant rules and regulations should be considered to ensure a safe journey. This study brings novelty to the fire safety analysis of EVs transportation onboard ships with using performance-based design and fire dynamics simulation tools to predict temperature level of the case incident. The Fire Dynamic Simulator was used for the simulations for the prediction of temperature distributions during an electric vehicle fire inside a ferry. The presented case study demonstrates how fire simulations could predict conditions for performance-based design of ferries that transport electric vehicles. Depending on simulations, temperature at initial times approximately 40s of fire incidents caused by EVs is around 1200°C and this cause severe results in terms of life and asset safety. In conclusion, this paper presents a brief insight to find an effective method for simulating and mitigating EV fires on ships to ensure crew safety and minimize fire damage.https://doi.org/10.14744/thermal.0000925https://dergipark.org.tr/tr/pub/thermal/issue/91063/166733
Probing Gluon Fluctuations in Nuclei with the First Energy-Dependent Measurement of Incoherent J/ψ Photoproduction in Ultraperipheral PbPb Collisions
No full textIncoherent <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi>J</a:mi><a:mo>/</a:mo><a:mi>ψ</a:mi></a:math> photoproduction in heavy ion ultraperipheral collisions (UPCs) provides a sensitive probe of localized, fluctuating gluonic structures within heavy nuclei. This Letter reports the first measurement of the photon-nucleon center-of-mass energy (<c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:msub><c:mi>W</c:mi><c:mrow><c:mi>γ</c:mi><c:mi mathvariant="normal">N</c:mi></c:mrow></c:msub></c:math>) dependence of this process in PbPb UPCs at a nucleon-nucleon center-of-mass energy of 5.02 TeV, using <f:math xmlns:f="http://www.w3.org/1998/Math/MathML" display="inline"><f:mrow><f:mn>1.52</f:mn><f:mtext> </f:mtext><f:mtext> </f:mtext><f:msup><f:mrow><f:mi>nb</f:mi></f:mrow><f:mrow><f:mo>−</f:mo><f:mn>1</f:mn></f:mrow></f:msup></f:mrow></f:math> of data recorded by the CMS experiment. The measurement covers a wide <h:math xmlns:h="http://www.w3.org/1998/Math/MathML" display="inline"><h:msub><h:mi>W</h:mi><h:mrow><h:mi>γ</h:mi><h:mi mathvariant="normal">N</h:mi></h:mrow></h:msub></h:math> range of <k:math xmlns:k="http://www.w3.org/1998/Math/MathML" display="inline"><k:mrow><k:mo>≈</k:mo><k:mn>40</k:mn><k:mi>–</k:mi><k:mn>400</k:mn><k:mtext> </k:mtext><k:mtext> </k:mtext><k:mi>GeV</k:mi></k:mrow></k:math>, probing gluons carrying a fraction <m:math xmlns:m="http://www.w3.org/1998/Math/MathML" display="inline"><m:mi>x</m:mi></m:math> of nucleon momentum down to an unexplored regime of <o:math xmlns:o="http://www.w3.org/1998/Math/MathML" display="inline"><o:mn>6.5</o:mn><o:mo>×</o:mo><o:msup><o:mn>10</o:mn><o:mrow><o:mo>−</o:mo><o:mn>5</o:mn></o:mrow></o:msup></o:math>. Compared to baseline predictions neglecting nuclear effects, the measured cross sections exhibit significantly greater suppression at lower <q:math xmlns:q="http://www.w3.org/1998/Math/MathML" display="inline"><q:mi>x</q:mi></q:math>. Additionally, the ratio of incoherent to coherent photoproduction is found to be constant across the probed <s:math xmlns:s="http://www.w3.org/1998/Math/MathML" display="inline"><s:msub><s:mi>W</s:mi><s:mrow><s:mi>γ</s:mi><s:mi mathvariant="normal">N</s:mi></s:mrow></s:msub></s:math> and <v:math xmlns:v="http://www.w3.org/1998/Math/MathML" display="inline"><v:mi>x</v:mi></v:math> range, disfavoring the establishment of the black disk limit. This Letter provides critical insights into the <x:math xmlns:x="http://www.w3.org/1998/Math/MathML" display="inline"><x:mi>x</x:mi></x:math>-dependent evolution of fluctuating gluonic structures within nuclei and calls for further advancements in theoretical models incorporating nuclear shadowing and gluon saturation.https://doi.org/10.1103/w9kp-f8x
Incorporating Seismic Zonation into Earthquake Catalog Declustering
No full text<title>Abstract</title> <p>Seismic hazard assessment relies upon a complete earthquake catalog, necessitating a declustering procedure to filter out dependent aftershocks or foreshocks from the earthquake catalog. Traditional declustering approaches, such as the Gardner-Knopoff approach, utilize magnitude-dependent temporal and spatial windows to distinguish dependent aftershocks/foreshocks from independent mainshocks. However, these approaches may overlook regional seismic characteristics, which leads to missing out primary independent events occurring within the time and space window following a strong earthquake, particularly when the background rate is elevated. This study proposes a modified declustering approach that employs seismic zonation as an additional parameter in the declustering procedure. The proposed methodology investigates adjustments to the magnitude term within the filtering window criteria based on the correlation of the seismic zone of a designated event with other events. A comparative analysis with the classical Gardner-Knopoff approach is conducted to evaluate the effectiveness of the proposed approach. The findings show that using seismic zonation in declustering improves the depiction of the distribution of seismic activity and reduces the likelihood of filtering out primary independent mainshocks.</p>https://doi.org/10.21203/rs.3.rs-6865502/v
Voltammmetric Assessment and Examination of the Interactions between Levetiracetam and DNA: Experimental Research, Molecular Docking, and Modeling Studies
No full textLevetiracetam (LEV) is an innovative antiepileptic medication utilized for the management of diverse seizure types associated with epilepsy. The present study aims to elucidate the molecular interaction mechanisms between LEV and fish sperm DNA (dsDNA) through a combination of spectroscopic techniques, viscosity measurements, and molecular docking analyses. Spectroscopic investigations, including UV absorption and fluorescence, confirm the formation of a complex between LEV and dsDNA. The groove binding process is indicated by the measured binding constant. Viscosity, dye‐displacement test, and DNA thermal denaturing investigations are used to confirm these results. Docking studies further verify the results, which show that LEV is linked to the minor groove of dsDNA. Furthermore, an LEV–dsDNA biosensor for low‐concentration LEV detection using the differential pulse voltammetry technique is created. A sensitive determination of LEV in pH 4.80 acetate buffer is made possible by the voltammetric examination of the peak current drop in the deoxyguanosine (dGuo) oxidation signals that resulted from the interaction between LEV and dsDNA. The oxidation signals of dGuo demonstrate a linear correlation within the concentration range of 2.5–20 μM LEV. The limit of detection and limit of determination are found to be 0.70 and 2.31 μM, respectively.https://doi.org/10.1002/open.202500191https://pubmed.ncbi.nlm.nih.gov/40605646/https://pmc.ncbi.nlm.nih.gov/articles/PMC12598790/https://avesis.kocaeli.edu.tr/publication/details/e07cf703-13ea-4af9-a17c-38be807cd69a/oa
Comparative Study of Surface Roughness in Upskin and Downskin Regions of Conformal Cooling Channel Sections Fabricated with AlSi10Mg, Ti64, 316L in AM-LPBF
No full textConformal cooling channel (CCC), used in many industries such as aviation, molding, biomedical, and robotics, refers to functional fluid channels that provide mass or energy transfer. CCC, which can be produced in limited forms where liquid flow cannot be fully achieved in traditional production technologies, is among the areas where additive manufacturing (AM) offers design freedom. However, in design-integrated CCC productions, sagging and deformation in the pipe section caused by the AM production process and design parameters can cause a decrease in the performance expected from the CCC and cause unpredictable flow problems. The producible CCC section from research constitutes the scope of this study. In this study, the production of cylindrical test specimens with eleven channel cross-sections between 0,4 mm and 9 mm using laser powder bed fusion (LPBF) technology using AlSi10Mg, 316L, and Ti64 materials and the roughness measurements of the upskin and downskin regions and the scanning electron microscope (SEM) examination are comparatively discussed. Inconsistent results were obtained in the surface roughness measurements of the 0,4 mm and 0,5 mm diameter holes considered within the scope of the research due to the diameter being below the production limits. This research shows that surface roughness in the upskin parameter region is more acceptable in all material types. In the laboratory measurements obtained, it is seen that the downskin region surface roughness value in the holes produced with AlSi10Mg is higher than other materials, and it is lower in the holes produced with Ti64 than other materials.https://doi.org/10.28979/jarnas.1652484https://dergipark.org.tr/tr/pub/jarnas/issue/93182/165248