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Compact and High-Performance QCA-Based Adder Design Using an Optimized XOR Logic Structure
No full textQuantum-dot Cellular Automata (QCA) has emerged as a viable nanotechnology for implementing ultra-dense, low-power digital logic circuits, offering significant advantages over traditional CMOS technology in terms of power consumption and device scalability. This paper presents an efficient design approach for constructing QCA-based half adder and full adder circuits using a novel, highly compact XOR gate configuration. The proposed XOR gate requires only 8 quantum dots, which significantly reduces the overall complexity and area of the arithmetic circuits. The design methodology utilizes the concept of half-cell distance optimization and effective cell-to-cell interaction to achieve reduced latency and minimal crossover usage. The QCADesigner simulation tool is employed to validate the correctness and performance of the proposed circuits. Comparative analysis is carried out against previously reported QCA-based adder designs, considering key performance metrics such as cell count, number of wire-crossings, and propagation delay. The simulation results reveal that the proposed half adder and full adder designs outperform existing counterparts in terms of compactness and operational efficiency. Furthermore, the proposed layouts are fully planar and do not require multilayer crossovers, thereby simplifying fabrication and enhancing practical applicability. The findings demonstrate that the compact XOR gate-based approach provides a scalable and power-efficient solution for implementing fundamental arithmetic operations in future nanoelectronic systems. This work highlights the potential of QCA as a next-generation design paradigm for low-power computing architectures
Research on Key Technology of Web Topic Detection Based on Tuple Semantic Description Analysis for Big Data
No full textIn the context of the numerical intelligence age, how to further promote research on Web topic detection with heterogeneous big data as an important research object has attracted widespread attention from scholars. This paper takes network heterogeneous big data as the main research object and proposes a Web topic detection idea based on tuple semantic description analysis. Firstly, the main implementation methods are explained, including time item analysis, named entity item analysis, event item analysis, and semantic formal analysis. Secondly, the Web topic detection algorithm based on tuple semantic description analysis is elaborated. Through experiments, firstly, the impact of the quantity of Web news on the quality of time item description and five tuple semantic description is analysed, the influence of the adjustment parameters in the algorithm on the quality of the described Web news named entity items is also analysed to obtain the optimal adjustment range for these parameters, the impact of the long and short time selection range in the algorithm on the calculation results of the popularity weight of Web news named entity items is also analysed to obtain its optimal adjustment range, the impact of the adjustment parameter in the algorithm on the quality of the described Web news event items is also analysed to obtain the optimal adjustment range of the parameter. Secondly, the quality of topic detection under different semantic descriptions in Web news, the time consumed in the topic detection process under different methods, and the quality of topic detection under different datasets are analyzed. The experimental analysis process shows that the Web topic detection idea proposed in this paper is feasible, verifiable, and superior, and can play an important role in reconfiguring the Web topic corpus, inferring the Web hierarchical big data propagation path, and providing the numerical intelligence warehouses based on network information detection
A Novel Fuzzy Cluster Head Selection and Adaptive Hawk Optimisation Routing Framework for Energy Efficient Wireless Sensor Networks
No full textWireless Sensor Networks (WSNs) have revolutionized various industries by enabling remote monitoring and data collection from inaccessible locations. However, they face significant challenges in data routing and cluster head selection due to limitations such as energy constraints, bandwidth, and dynamic environments. These challenges arise as nodes may fail due to energy depletion, causing changes in network topology. Efficient communication between cluster heads and the base station is essential, as long-distance data transmission consumes substantial energy, leading to rapid node depletion and reduced network lifetime. To address these issues, this paper proposes a novel Fuzzy-based Cluster Head Selection (FCHS) algorithm that dynamically elects cluster heads based on multiple criteria, including residual energy, distance to the base station, and node density. The FCHS algorithm ensures that cluster heads are selected in a manner that optimizes energy utilization, considering the diverse conditions in a WSN. In addition, an Adaptive Hawk Optimization (AHO) algorithm is employed to optimize data routing between cluster heads and the base station. The AHO algorithm dynamically adapts to changes in network topology, selecting the most energy-efficient paths for data transmission, thereby reducing overall energy consumption. The proposed FCHS-AHO approach is evaluated against existing cluster head selection and routing methods. Simulation results demonstrate that the FCHS-AHO method outperforms traditional techniques in terms of energy efficiency, network lifetime, and data delivery reliability. By optimizing both cluster head selection and routing, this framework significantly enhances the overall performance of WSNs, particularly in dynamic and resource-constrained environments. The proposed method provides a robust solution for improving the sustainability and reliability of WSNs in real-world applications
Ultrastructural features of cypselae in selected Senecio L. (Asteraceae) species
Get PDFIn this study, the cypsela features of eight Senecio species in Türkiye (Senecio olympicus Boiss., S. paludosus L., S. tauricolus VA. Matthews, S. salsuginea H. Duman & Vural, S. castagneanus DC., S. fluviatilis Wallr., S. pseudo-orientalis Schischk., and S. racemosus (M. Bieb.) DC.) were investigated in detail using light microscopy (LM) and transmission electron microscopy (TEM). A very thick and darkly stained cuticle layer was observed on the epidermal cells of all the species examined. Papillae were observed only in epidermal cells of S. olympicus Boiss, and sclerenchyma cells were less developed in the cypsela. In the other seven species, well-developed sclerenchyma tissue was found along the pericarp wall in the form of a semicircle, in bundles, or around the secretory ducts. Although secretion ducts were observed along the cypsela wall in the mid-layer cells of S. olympicus, S. tauricolus, S. castagneanus, and S. fluviatilis, no secretion ducts were observed in the other four species. Although prismatic calcium oxalate crystals were observed in the intermediate (mid) layer of S. tauricolus, S. castagneanus, and S. pseudo-orientalis, no crystals were found in the other five species. Phytomelanin accumulation was found in the schizogenic spaces between the outer and intermediate layers of S. olympicus, S. paludosus, S. tauricolus, S. castagneanus, S. pseudo-orientalis, and S. racemosus, but not in S. salsuginea and S. fluviatilis
Novosti: Dr. sc. Anamarija Pulitika dobitnica je nagrade Hrvatskih voda zanajboljudoktorskudisertaciju u 2025. godini
Get PDFAutomatic Detection of Surface Damage on Forest Roads Using Mobile LiDAR and GIS Processing Tools
Get PDFIn this study, a method of automatically detecting carriageway edges and damaged areas on the surface of forest road wearing courses was tested based on high-density LiDAR data acquired using a handheld mobile laser scanning device. The results were compared with those of current tacheometric methods. Whereas most previous studies have focused on detecting road segments or objects and road centrelines using object-oriented classifications or support vector machine (SVM) algorithms, our research was directed to detect forest carriageway edges and road surface deterioration. Forest roads are designed with a 20-year lifespan before structural failures affect up to 25% of the surface area. We developed an automatic method for detecting damaged areas in the wearing course using GIS tools in ArcGIS Pro. According to the carriageway edges, an overestimation was found between the areas detected automatically and those surveyed tacheometrically, with the automatically detected area being 28% larger. However, it was also found that most of the damage detected was within the tacheometrically surveyed carriageway edges (89%). Agreement between the damage boundary overlaps was relatively low; at 57%, the total damage area detected automatically was 19% larger than that surveyed tacheometrically. The results show that the new automatic process can provide more precise, objective data, as tacheometrical methods can be influenced by the individual approach of a surveyor. Simple and quick detection of damaged areas allows assessing the condition of forest road surfaces and determining repair priorities
The first attempts of plant reintroductions on the Drava River in Croatia: experiences with dwarf cattail (Typha minima Funck ex Hoppe)
No full textReintroduction of key plant species to habitats where they became locally extinct contributes to the restoration of biodiversity and ecological functions of the natural ecosystem. The dwarf cattail (Typha minima Funck ex Hoppe) is a pioneer plant, adapted to newly formed gravel- and sand bars of free-flowing rivers, and it is an indicator species of rivers with natural hydro-morphological sediment dynamics and a changing riverbed. In the last decades, it has disappeared from known sites on the banks of the Drava River near Varaždin, Donja Dubrava and Legrad, and therefore its reintroduction was planned and carried out within the framework of the DRAVA LIFE project. Pieces of rooted rhizomes of the dwarf cattail originating from the upper sections of the Drava River in Austria were planted on three occasions (2018, 2019 and 2024) at selected locations near the Drava-Mura confluence. Monitoring revealed that most plants (83% from the total of 1285), did not survive long-term floods; they were buried by sediments or carried away by strong currents. From the 17% of plants that survived the floods, 9% were dug up by wild boars. Only about 8% of the plants survived until the end of the year in which they were planted. Despite the lower rate of success, the reintroduction of this species should be continued by planting rhizomes or seedlings in micro-locations with potentially more favourable conditions, such as newly restored Drava side arms, where the river dynamics is more moderate, and the newly created bare surfaces are potentially suitable habitats
SECURITY ASPECTS OF KNOWLEDGE MANAGEMENT
No full textUpravljanje znanjem postaje ključni čimbenik uspjeha suvremenih organizacija koje se suočavaju s brzim tehnološkim promjenama i rastućom količinom podataka. Međutim, dok učinkovito upravljanje znanjem može povećati inovativnost i konkurentnost, istovremeno otvara niz sigurnosnih izazova.
Ovaj rad istražuje sigurnosne aspekte upravljanja znanjem, s posebnim naglaskom na zaštitu povjerljivih informacija, intelektualnog vlasništva te sigurnost digitalnih sustava za pohranu i dijeljenje znanja. Analiziraju se prijetnje poput neovlaštenog pristupa, curenja podataka te rizika povezanih s ljudskim faktorom. Kroz pregled literature i primjere iz prakse, rad ističe važnost integracije sigurnosnih mjera u sve faze ciklusa upravljanja znanjem – od prikupljanja i pohrane do distribucije i primjene.
Zaključno, sigurnost upravljanja znanjem ne smije se promatrati kao tehničko pitanje već kao sastavni dio organizacijske strategije koja osigurava dugoročnu održivost i zaštitu konkurentskih prednosti.Knowledge management is becoming a key success factor for modern organizations facing rapid technological change and growing amounts of data. However, while effective knowledge management can increase innovation and competitiveness, it also opens up a number of security challenges.
This paper explores the security aspects of knowledge management, with a particular focus on the protection of confidential information, intellectual property, and the security of digital systems for storing and sharing knowledge. Threats such as unauthorized access, data leakage, and risks related to the human factor are analyzed. Through a literature review and practical examples, the paper emphasizes the importance of integrating security measures into all phases of the knowledge management cycle – from collection and storage to distribution and application.
In conclusion, knowledge management security should not be viewed as a technical issue but as an integral part of an organizational strategy that ensures long-term sustainability and protection of competitive advantages
Influence of the Rail Vehicle Layout on Efficiency and Railway Operation
No full textRailway efficiency is increasingly significant given the competition with road and air transport, where usability of travel time, passenger comfort and operational reliability play key roles. This study investigates the influence of passenger rail vehicle layout on efficiency, focusing on aspects such as passenger changeover time, luggage storage, seating usability and overall comfort. Since 2001, empirical research at TU Wien has combined extensive passenger observations, surveys of more than 60,000 travellers, detailed luggage measurements and video analyses of over 20,000 boarding and alighting processes, complemented by controlled changeover tests in multiple vehicle layouts. These data informed the development of a calculation model and the TrainOptimizer software to evaluate and optimise layouts. Findings show that maximising seating capacity often reduces efficiency by limiting luggage storage, blocking seats and extending changeover times, whereas layouts with fewer but better-positioned seats and distributed luggage racks increase usable capacity and passenger satisfaction. Results also indicate that interior design directly affects time use, stress and well-being during travel. The study concludes that vehicle design has a significant impact on operational performance, energy use and the competitive position of railways, with well-balanced layouts offering both higher efficiency and an enhanced passenger experience
DRUŠTVENE PREDRASUDE I NJIHOV UTJECAJ NA OGRANIČAVANJE PROFESIONALNOG RAZVOJA ŽENA – EMPIRIJSKI PRISTUP
No full textThe considerations contained in this article relate to the broad issue of discrimination against women in the labour market. In this respect, the aim of the study is to verify the areas in which women feel discriminated against in the labour market and which impact on the inhibition of their professional development. In the first part, a review of the literature is carried out, where the terms stereotype, prejudice and discrimination are defined. In this respect, the types of discrimination occurring in the labour market are also indicated. The empirical part presents the results of own research. Following on from the above, a preliminary survey was conducted with 310 respondents from Poland at the beginning of 2024. It concerned an assessment of society's views on the role of women in various dimensions of the socio-economic environment. Based on the respondents' answers, a verification of the employment areas in which women feel discriminated against was carried out. Furthermore, using the econometric package GRETL, an Ordinary Least Squares method (OLS) was used to assess the relationship between these areas. The final section presents detailed conclusions and identifies limitations and recommendations for further research.Razmatranja sadržana u ovom članku odnose se na široko pitanje diskriminacije žena na tržištu rada. S tim u vezi, cilj je istraživanja provjeriti područja u kojima se žene osjećaju diskriminiranima na tržištu rada i koja utječu na inhibiciju njihova profesionalnog razvoja. U prvom dijelu donosi se pregled literature, gdje se definiraju pojmovi stereotipa, predrasuda i diskriminacije. U tom smislu također su naznačene vrste diskriminacije koje se javljaju na tržištu rada. Empirijski dio predstavlja rezultate vlastitog istraživanja. Nastavno na navedeno, početkom 2024. godine provedeno je preliminarno istraživanje s 310 ispitanika iz Poljske. Odnosilo se na procjenu stavova društva o ulozi žena u različitim dimenzijama socioekonomskog okruženja. Na temelju odgovora ispitanica provedena je provjera područja zapošljavanja u kojima se žene osjećaju diskriminiranima. Nadalje, primjenom ekonometrijskog paketa GRETL, metoda običnih najmanjih kvadrata (OLS) korištena je za procjenu odnosa između ovih područja. Posljednji dio predstavlja detaljne zaključke i identificira ograničenja i preporuke za daljnja istraživanja