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Research on deep learning-based network intrusion detection methods for smart ships
Get PDFAs the development of intelligent ships rapidly progresses, the importance of maritime network security escalates. Intrusion Detection Systems (IDS) serve as a pivotal defense mechanism against cyberattacks targeting these vessels. To augment the efficacy of IDS in detecting anomalous network traffic, this paper introduces a novel intrusion detection method utilizing both Transformer and Kolmogorov-Arnold Networks (KAN), designated as Transformer-KAN. This approach effectively mitigates the limitations of traditional intrusion detection algorithms, which include inadequate feature extraction capabilities and the excessive parameterization required to delineate complex patterns. The proposed method employs a Transformer encoder to discern long-range dependencies within input sequences, while KAN layers enhance the model’s ability to approximate complex patterns through non-linear transformations. This integrative strategy ensures elevated accuracy for the intrusion detection algorithm and proves particularly beneficial in intelligent ship environments, where training data may be sparse or computational resources limited. Experimental results confirm that the Transformer-KAN model attains exceptionally high accuracy in both binary and five-class classification tasks, outperforming the capabilities of standalone Transformer and KAN models. Comparative analyses with conventional algorithms—such as Convolutional Neural Networks (CNN), Gated Recurrent Units (GRU), Deep Belief Networks (DBN), and Support Vector Machines (SVM)-further substantiate the superior effectiveness of the proposed method. This research establishes a new theoretical framework and provides a direction for the practical implementation of network security measures in contemporary intelligent ships
Productivity, Costs and Residual Stand Damage of Timber Harvesting Methods in Scots Pine Stands with Extended Distance Between Skid Trails
Get PDFIn forest operations, economic advantages can be obtained by increasing the distance between the skid trails. This protects soil by reducing the compacted area, while at the same time increasing the productive timber ground area. These advantages are offset by disadvantages, as fully mechanized timber harvesting is not possible and motor-manual felling is required for the areas that cannot be reached by the harvester. This in turn reduces work safety and increases the workload and personnel requirements, possibly leading to higher timber harvesting costs.
To analyze the consequences of an extended skid trail distance, a timber harvest under real conditions was carried out in north-eastern Germany in the fall of 2023. In a 72-year-old Scots pine (Pinus sylvestris, L.) stand with an area of 23.2 ha, 692 m³ of wood was harvested in a thinning operation. Three different timber harvesting methods with extended skid trail distances of approx. 40 m (ES) were investigated and compared to a fully mechanized system with conventional skid trail distances of approx. 20 m (CS) in a time study with a total of 150 recorded hours. Following the harvest, the residual stand damage was also recorded.
The timber harvesting methods with ES had higher timber harvesting costs than the method with CS, although there are major differences between the three semi-mechanized timber harvesting systems: The productivity of the harvester increases as the number of passes by the harvester decreases (from 13.87 to 14.09 to 15.99 m³/PMH15). Looking at the forwarder productivity, it is higher in ES than in CS. Finally, the costs of the harvesting systems ranged between 29.18 €/m³ for CS to 30.40, 32.41, 34.56 €/m³, respectively, for ES. There is no significant difference in the residual stand damage across the methods. The productivity of semi-mechanized timber harvesting methods can be improved if the motor-manual felling is carried out before the harvester is used and if the trees are not winched with a cable tractor
INTEGRIRANA ANALIZA NEOGENSKE DO KVARTARNE BIOSTRATIGRAFIJE NANOFOSILA I BRZINE SEDIMENTACIJE U SEKVENCIJI CIKARANG, BAZEN SJEVEROZAPADNE JAVE, INDONEZIJA
No full textNannofossil assemblages were found throughout the Neogene to Quaternary rock sequence at Cikarang in the Northwest Java Basin, Indonesia. This study determines the biostratigraphic age, reconstructs depositional phases and calculates the sedimentary rate of the rock sequence based on lithology and nannofossil assemblages. Within this sequence, 59 nannofossil species can be identified and 14 are index fossils with easily recognizable first occurrence (FO) or last occurrence (LO). Based on these boundaries, the sequence is divided into 17 biostratigraphic zones categorized into range and interval zones. Lithology successions in Cikarang are generally composed of fine-grained clastic rocks (sandstone and claystone), clastic limestone and fossil reefs, which are deposited in various depositional environments such as deep marine, shallow marine and littoral. Sedimentation rates vary between 4.18 m/Myr to 217.87 m/Myr, reflecting the influence of tectonic activity, sea level changes and sediment supply. Unconformities are identified at the intra Miocene, as well as Mio-Pliocene and Plio-Pleistocene boundaries.Zajednice nanofosila pronađene su u cijelome neogenskom do kvartarnom slijedu stijena u Cikarangu u bazenu Sjeverozapadne Jave u Indoneziji. U okviru ovoga istraživanja određena je biostratigrafska starost, rekonstruirane su faze taloženja te je izračunana brzina sedimentacije slijeda stijena na temelju litologije i zajednica nanofosila. Unutar ovoga slijeda identificirano je 59 vrsta nanofosila, a 14 su indeksni fosili s lako prepoznatljivim prvim (FO) ili posljednjim pojavljivanjem (LO). Na temelju tih granica slijed je podijeljen u 17 biostratigrafskih zona kategoriziranih u rasponske i intervalne zone. Litološke sukcesije u Cikarangu općenito su sastavljene od sitnozrnatih klastičnih stijena (pješčenjaka i gline), klastičnih vapnenaca i fosilnih grebena, koji su taloženi u različitim taložnim okruženjima kao što su dubokomorski, plitkomorski i litoralni. Brzine sedimentacije variraju između 4,18 m/Myr do 217,87 m/Myr, što odražava utjecaj tektonske aktivnosti, promjene razine mora i donosa sedimenta. Nepodudarnosti su identificirane unutar miocena, kao i na granicama miocena i pliocena te pliocena i pleistocena
PREGLED RECENTNIH ISTRAŽIVANJA NA PODRUČJU MODELIRANJA SPREGNUTOGA PRIJENOSA TOPLINE U TRANSFORMATORIMA
No full textThe exact position and the value of the hot-spot temperature in a transformer could be estimated by calculation using computational fluid dynamics. However, this approach requires the usage of significant computational resources. In this paper, a review on some recent investigations on this topic is made, focusing thereby primarily on the investigation in which the field distribution of the dependent variables is taken into consideration in a conjugate heat transfer problem. Still, the determination of the hot-spot temperature in the transformer is an open problem. Furthermore, a review on some fundamental aspects related to the heat transfer in the transformer was made, and some new approaches for the calculation of heat transfer in the transformer were proposed: smoothed-particle hydrodynamics, two-fluid model and the application of T-Flows computational software. Thus, the smoothed-particle hydrodynamics is found as a convenient approach, since it is traditionally related to laminar flow, that is present in the transformer; the two-fluid model significantly saves the computational resources, while the application of the computational software T-Flows is free and extremely powerful for computation of conjugate heat transfer and parallel computation. The conducted research defined the guidelines for the future work in numerical modelling of heat transfer in transformers.Točan položaj i iznos najviše temperature materijala izolacije unutar transformatora proračunski se može utvrditi korištenjem računalne dinamike fluida. Međutim, ovaj pristup zahtijeva korištenje znatnih računalnih resursa. U ovome radu napravljen je pregled nekih nedavnih istraživanja na ovu temu fokusirajući se pritom ponajprije na istraživanja u kojima je u obzir uzeta prostorna distribucija zavisnih varijabli u problemu spregnutoga prijenosa topline. Određivanje najviše temperature izolacije unutar transformatora još uvijek je otvoreno pitanje. Nadalje, napravljen je osvrt na fundamentalne aspekte vezane uz prijenos topline unutar transformatora te su predloženi neki novi pristupi za proračun prijenosa topline transformatora: uglađena hidrodinamika čestica, dvofluidni model i primjena računalnoga programa TFlows. Tako se uglađena hidrodinamika čestica pokazala prikladnim pristupom jer je tradicionalno vezana uz laminarno strujenje kakvo se pojavljuje unutar transformatora; dvofluidni model znatno štedi računalne resurse, dok je primjena računalnoga programa T-Flows besplatna, a izrazito snažna za proračun spregnutoga prijenosa topline i paralelno računanje. Provedenim se istraživanjem definiraju smjernice za daljnji rad na području numeričkoga modeliranja prijenosa topline unutar transformatora
Doubly effective one round election model: Improving efficiency and fiscal savings
No full textElectoral processes are usual in most countries around the world. The most dominant electoral system is the standard Two-Round System (TRS). Despite the variety of models for electing public representatives, all result in public expenditure. In democratic societies, we cannot avoid such an expense, but we can minimize it. Minimizing expenses in line with simplicity and justice of the electoral processes is the primary goal of this paper. We propose an entirely new one-round election model that can replace and successfully simulate the existing two-round model. Our proposed solution is unique, and we have named it the Doubly Effective One Round election model (DEOR election model). The literature contains many similar approaches, such as Ranked Choice Voting (RCV)/Instant-Runoff Voting (IRV), Single Transferable Vote (STV), Approval Voting, or Majority Judgment, but this proposed model is entirely new. As the new model is based on a ranking method, it offers additional advantages and possibilities, which are explained and illustrated through several examples in the paper. In addition to its efficiency, the application of this model can bring significant fiscal savings
ANALYSIS OF SECURITY THREATS AND PROTECTION MEASURES IN REMOTE ELECTRICITY METER READING SYSTEMS
No full textU ovom radu analiziraju se metode očitanja električne energije s posebnim naglaskom na sigurnosne aspekte i ekonomsku isplativost sustava daljinskog očitanja brojila. Rad obuhvaća usporedbu tradicionalnih metoda očitanja, samoočitanja korisnika i daljinskog očitanja kroz kriterije troškova, točnosti, učinkovitosti i sigurnosti podataka. Posebna pažnja posvećena je sigurnosnim rizicima daljinskog očitanja te mjerama zaštite od kibernetičkih napada i njihovoj ulozi u očuvanju povjerljivosti i integriteta podataka. Metodologija rada temelji se na pregledu relevantne literature i komparativnoj analizi isplativosti pojedinih metoda. Rezultati analize pokazuju da daljinsko očitanje, uz primjenu standardiziranih sigurnosnih mehanizama poput enkripcije i kontrole pristupa, pruža višu razinu sigurnosti i operativne učinkovitosti te predstavlja dugoročno održivo i pouzdano rješenje, unatoč većim početnim troškovima implementacije.This paper analyses different methods of electricity consumption reading with a particular focus on security aspects and the economic feasibility of remote electricity meter reading systems. The study compares traditional manual reading, customer self-reading and remote reading based on criteria such as costs, accuracy, efficiency and data security. Special attention is given to security risks associated with remote meter reading, as well as to protection measures against cyber-attacks and their role in preserving data confidentiality and integrity. The methodology is based on a review of relevant literature and a comparative analysis of the economic feasibility of individual reading methods. The results of the analysis indicate that remote meter reading, when supported by standardised security mechanisms such as encryption and access control, provides a higher level of security and operational efficiency and represents a reliable and long-term sustainable solution, despite higher initial implementation costs
Contemporary Readers’ Memory of Marko Marulić and Older Croatian Literature
No full textOsim obilježavanja obljetnica, postoje različiti drugi načini kojima se može procijeniti važnost života i djela nekoga pisca u danoj kulturi i književnosti. Ovaj će rad na uzorku Marka Marulića pokušati predstaviti novi način da se procijeni koliko je dani pisac tekstualno prisutan u kvantitativno najzastupljenijem dijelu suvremene hrvatske književnosti, a to su neprofesionalni čitatelji. Procjena će se sastojati od analize podataka iz empirijskog istraživanja velikoga broja (1005) hrvatskih neprofesionalnih čitatelja, koji su u višegodišnjem istraživanju upitani o tome koje književne tekstove najbolje pamte, uz određena potpitanja. U prvome će se dijelu rada stoga ukratko predstaviti metodologija i cilj istraživanja, da bi se u drugome prešlo na rezultate i kontekstualizaciju odabranoga korpusa te u trećemu na zaključke koji iz toga proizlaze.The paper utilizes an empirical research project about everyday readers of literature in order to ascertain the presence of Marko Marulić as a writer in the cultural memory of contemporary Croatian readers. It outlines the relevant results of the project before situating Marulić as one of the few (less than 3% of the total 1374) remembered authors who wrote prior to the 19th century. Snippets from the single interview in which a respondent focused on one of Marulić’s works (Judita) are presented, followed by three other groups of interview snippets in which Marulić is associated primarily with the contexts of public presence (six readers), intertextual association (five readers), and required reading (nine readers). These results and interview snippets are then analyzed, showing that “Marulić” is remembered as a cultural signifier among contemporary Croatians, although usually as part of a broader author agglutination that refers to a number of older literary authors and genres, which incidentally makes such associations prone to errors. In conclusion, his presence as an author in cultural memory is affirmed on a scale ranging from being a positive symbol to signifying bibliotrauma, while at the same time his literary texts are found to be all but forgotten among contemporary readers
Application of Sustainable Infrastructure Criteria in Railway Projects with the Input–Process–Output–Outcome Approach
No full textPresent-day societies face unprecedented dependence on built infrastructure amid escalating sustainability challenges including climate change and social inequality. Railway infrastructure, positioned as the most environmentally sustainable transport mode, presents a critical paradox: while essential for sustainable mobility, much of the existing network was built when environmental awareness, accessibility and innovation-driven technologies were not design priorities. This creates a significant research gap in how railway infrastructure can be systematically aligned with current sustainability frameworks such as the UN Sustainable Development Goals (SDGs), Paris Agreement and regional policy initiatives. This study addresses this gap by developing a comprehensive decision-making model that integrates railway-specific sustainability criteria defined in the previous study within an input-process-output-outcome (IPOO) framework. The approach enables infrastructure management organisations to evaluate investment projects beyond immediate operational efficiency, incorporating medium- and long-term impacts that strengthen system resilience. The framework was validated through application to Latvian railway infrastructure investment scenario. Results demonstrate that the IPOO methodology enables infrastructure managers to trace causality from resource allocation decisions through transformation processes to both immediate outputs and long-term societal impacts. Expert panel validation confirmed practical applicability while identifying critical enhancement requirements across all IPOO components. These findings contribute to sustainable infrastructure assessment theory by providing 64 railway sector-specific indicators aligned with broader SDG frameworks. Practically, the model enables railway infrastructure management companies to systematically assess investment projects for medium- and long-term transformative potential, while offering policymakers a structured approach for developing targeted resilience strategies. This research advances the integration of sustainability science with infrastructure decision-making
Aerodynamics of Freight Trains – Addressing the Complexity of Train Geometry through an Open Database
No full textThe study of the aerodynamics of freight trains is important for safety, efficiency and reducing damage during the operation of freight trains. It is also very important for the accurate estimation of drag resistance and, correspondingly, of the required traction effort. Computational fluid dynamics (CFD) is often used to investigate air flows around a freight train and their effects on vehicle dynamics, especially on drag, slipstream and pressure pulses in tunnels. Most of these studies, however, considered container wagons, while a much wider variety of wagon types are currently used. Therefore, there is a need for further research investigating the aerodynamics of more freight train geometries. This involves intensive work investigating realistic wagon geometries and generating representative generic versions. Subsequently, a complex freight train can be generated from these generic building blocks. To address the need for efficient production of these consists, a database of representative wagon and locomotive geometries was created. In this work, the geometry database is presented and is used to generate realistic freight train geometries suitable for CFD analyses. Then, selected results of CFD simulations performed using the geometries generated from the database are presented, demonstrating the use of the tool
Green Corridors as a Tool for Spatial Connectivity and Sustainable Development
No full textZeleni koridori predstavljaju važan element zelene infrastrukture koji omogućuje funkcionalno, ekološko i društveno povezivanje urbanih, ruralnih i prirodnih prostora. U Sisačko-moslavačkoj županiji, obilježenoj raznolikim krajobrazima, depopulacijskim trendovima i velikim udjelom šumskih i poljoprivrednih površina, njihova planska uspostava ima poseban značaj za održivi prostorni razvoj. Cilj ovog rada je analizirati mogućnosti primjene parkovnih tehnika u oblikovanju mreže zelenih koridora te ukazati na ulogu šumarske struke u integraciji postojeće prometne i šumske infrastrukture u sustav pješačko-biciklističkog povezivanja prostora. Metodološki pristup temelji se na kombinaciji terenske i uredske analize, prostorne interpretacije te tipološke razrade profila staza i parkovnih elemenata. Analizirano je ukupno 16 zelenih koridora koji povezuju ključna naselja, prirodne i kulturne vrijednosti županije. Za svaki koridor identificirane su dominantne kategorije prometnica, primijenjeni profili staza te planirane parkovne tehnike i prostorne funkcije. Rezultati su objedinjeni u sumarnoj Tablici 1 koja omogućuje preglednu usporedbu i evaluaciju rješenja. Dobiveni rezultati ukazuju na značajan potencijal postojećih šumskih prometnica i nerazvrstanih cesta za nenametljivo uključivanje u mrežu zelenih koridora, uz minimalne prostorne intervencije. Parkovne tehnike, poput odmorišta, interpretacijskih točaka i jednostavnih prijelaza, imaju ključnu ulogu u povećanju sigurnosti, čitljivosti i korištenja prostora. Posebno se ističe doprinos šumarske struke u planiranju, gospodarenju i razvoju ovakvih sustava, s naglaskom na očuvanje krajobraznih vrijednosti i multifunkcionalnu uporabu prostora. Rad daje stručni okvir i praktične smjernice za daljnji razvoj zelenih koridora kao alata održive mobilnosti, rekreacije i prostorne kohezije u ruralnim i rubnim područjima.Green corridors are increasingly recognized as a key component of green infrastructure in spatial and landscape planning, particularly in the context of sustainable development, active mobility, and the functional integration of urban, rural, and natural areas. They are commonly defined as linear spatial elements that ensure the continuity of ecological, recreational, and social functions while simultaneously connecting settlements, natural habitats, and cultural landscapes. Within contemporary European planning frameworks, green corridors are promoted as multifunctional spatial tools that contribute to biodiversity conservation, climate adaptation, and improved quality of life for local communities.This paper presents a methodological and applied framework for planning a network of green corridors, based on the integration of existing transport and forest infrastructure and the application of selected park design techniques. The research was conducted in a spatially heterogeneous region characterized by extensive forest complexes, river valleys, agricultural land, and dispersed settlements. Such spatial conditions create favorable prerequisites for the development of green corridors, but also pose challenges related to depopulation, limited mobility options, and fragmented planning approaches.The main objective of the study was to analyze the possibilities of establishing a functional network of green corridors by using the existing infrastructure with minimal spatial intervention. Special emphasis was placed on the role of forestry expertise in spatial connectivity, landscape interpretation, and sustainable use of forest road networks. The specific objectives were to (i) identify and analyze the spatial characteristics of fifteen proposed green corridors, (ii) determine suitable trail profiles and park techniques in relation to different spatial contexts, (iii) present a synthetic overview of planning solutions through a comparative table, and (iv) discuss the contribution of forestry professionals to interdisciplinary green infrastructure planning.The research methodology combined desk-based spatial analysis, field observations, and the synthesis of professional planning criteria. The existing road networks, including local, unclassified, and forest roads, were analyzed and classified according to their potential for pedestrian and cycling use. Forest infrastructure was interpreted not only as a production-oriented system but also as a valuable spatial resource for recreational and connective functions. Based on spatial context and functional requirements, four basic trail profile types (S-TIP 1–4) were defined (Figures 1–4) and applied across the analyzed corridors.The results are presented through a comprehensive table (Table 1) that summarizes the key characteristics of all sixteen green corridors, including corridor designation, start and end points, categories of transport infrastructure, applied trail profiles, planned park techniques, dominant functions, and spatial contribution. The analysis demonstrates that most corridors rely on a combination of existing local roads and primary or secondary forest roads, confirming that functional green corridors can be established without extensive new infrastructure development (Figure 5). Trail profiles are clearly differentiated according to spatial context: urban and peri-urban areas predominantly require separated or traffic-calmed profiles, while rural and forested areas allow for more flexible and low-impact solutions.Planned park techniques are intentionally modest and context-sensitive, focusing on rest areas, interpretative panels, viewpoints, and simple park elements. This approach emphasizes spatial connectivity and legibility over intensive park equipment, reinforcing the multifunctional nature of green corridors. The study also highlights the importance of forestry professionals in planning processes, particularly in integrating forest roads into green infrastructure networks in a way that preserves ecological, production, and social forest functions.The discussion places the results within a broader interdisciplinary context, linking forestry, spatial planning, landscape architecture, and sustainable mobility. Green corridors are interpreted not merely as recreational trails, but as spatial structures that support active mobility, cultural and natural heritage interpretation, and balanced regional development. The proposed methodological framework demonstrates transferability and can be applied in other regions with similar spatial characteristics.In conclusion, the paper confirms that green corridor planning based on the existing infrastructure and forestry expertise represents an effective and sustainable approach to spatial connectivity. The presented methodology and results provide a practical planning tool and a professional basis for further development of green infrastructure networks, while also supporting a stronger role of forestry professionals in interdisciplinary spatial planning and landscape management