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Prediction Algorithm for Aerospace Product Quality Classification
No full textProductive activities in aerospace industry are characterized by their use of multiple species, small batches, discrete types etc. Therefore, the quality classification of aerospace products is a typical small-sample classification problem. The existing general algorithms are inadequate for an effective classification as well as prediction of aerospace production quality. To fill the gap, the research presents a specialized algorithm to the classification prediction of aerospace production quality by integrating isometric feature mapping (ISOMAP) with support vector machine (SVM). The accuracy of each main kernel function is compared, followed by a determination of the algorithm model using a radial basis function (RBF). Experiments show that the proposed algorithm significantly improves classification and prediction accuracy for aerospace product quality, thereby enabling the timely identification of potential quality issues and the subsequent reduction of quality issues in aerospace products
Remaining Life Assessment of a Power Plant Steam Pipeline Containing Cavities Using the Replica Method
No full textAssessing the condition of welded steam pipes is a key activity for the safe operation of the power plant and preventing future failures. This paper presents a method of estimating the remaining service life of a steam pipeline made of high-alloy steel, which has been in operation for a long time. The tested steam pipeline, operating for a long period of time under high pressure and high temperature conditions, experiences a series of microstructural transformations in both the base material and the weld, including cavitation due to creep. This study shows how, based on the examined microstructure, to estimate the remaining service life of a steam pipe under creep conditions, using the method of non-destructive replication metallography. Based on the classification of damage due to creep according to Wedel and Neubauer, an assessment of the remaining service life of the steam pipeline was made. The test results indicate that after long-term operation, noticeable microstructural damage occurs due to creep, and the estimated remaining service life indicates that the tested steam pipeline meets the conditions for further use. The purpose of this paper is to show the microstructural changes of a steam pipe made of high-alloy steel X10CrMoVNb9-1 after long-term operation in creep conditions. The presented data provide technical support for the safe operation of the high-temperature steam pipeline in the power plant, helping to formulate a maintenance strategy and eventual replacement of the steam pipeline, in order to ensure the safe and efficient operation of the power plant
Metaheuristic Optimization for Deep Learning in Plant Disease Detection: A Hybrid Approach
No full textThis study investigates metaheuristic hyperparameter optimization for deep learning–based plant disease detection across two datasets: Dataset A (1,530 images; three classes: Healthy, Powdery, Rust) and a large multi-crop corpus evaluated in a binary Healthy/Diseased setting with an 80/20 training–validation split. A hybrid optimizer is proposed that interleaves Dragonfly Algorithm (DA) for population-wide exploration with Firefly Algorithm (FA) for elite intensification (DA–FLA), and is applied to five pretrained CNN backbones (DenseNet, VGG19, InceptionV3, MobileNet, Xception). All models are trained under an identical 50-epoch protocol. On Dataset A, DenseNet provides the strongest baseline (accuracy/macro-F1 = 0.9733/0.9735), which rises to 0.9800/0.9800 with DA–FLA tuning. On the large-scale binary corpus, Xception and DenseNet perform competitively (≈0.9846 macro-F1 and 0.9838 macro-F1, respectively), while the optimized Xception attains 0.9924 accuracy and 0.9913 macro-F1. A one-way ANOVA with Tukey HSD confirms significant performance differences (p < 0.001), with optimized Xception outperforming all comparators. The hybrid search introduces modest training overhead but leaves inference cost essentially unchanged. Results demonstrate that balancing global exploration with local exploitation yields reproducible, statistically supported gains, advancing accurate and efficient plant disease diagnostics suitable for mobile/edge deployment and supporting early intervention and sustainable farming practices
Source rocks of the External Dinarides, Croatia
No full textThe External Dinarides, with an abundance of both autochthonous and allochthonous organic matter, have been the subject of sustained petroleum exploration by INA – Industrija nafte, d.d.(INA), Croatia’s national oil company, since the 1960s. To evaluate the residual hydrocar-bon potential, a comprehensive suite of geochemical analyses, encompassing over 5,000 samples from drill cores, cuttings, outcrops, and formation fluids, have been performed. These investigations have delineated potential source rocks within various stratigraphic horizons and established critical genetic linkages between these source rocks and generated hydrocar-bons, thereby refining the understanding of the region’s petroleum systems. This article syn-thesizes INA’s key findings derived from the extensive source rock data analysis, offering valuable insights into the remaining hydrocarbon prospectivity of the External Dinarides
Metode pronalaska i instrumentacija sekundarnog meziobukalnog kanala u prvom gornjem kutnjaku
No full textPronalazak i instrumentacija sekundarnog mezibukalnog kanala (MB2) prvog gornjeg molara vrlo su izazovni zbog njegove specifične, promjenjive anatomije. Brojna istraživanja pokazala su da se pojavljuje u visokom postotku te da upravo njegovo izostavljanje dovodi do ponovnih infekcija, nakupljanja mikroorganizama te posljedično neuspjeha terapije. Kako bi lakše locirali MB2, od velike su nam pomoći suvremene metode vizualizacije, mikroskop i lupe. Njegova učestalost varira i ovisi o mnogim faktorima, samoj populaciji i korištenoj dijagnostičkoj metodi. Neki od problema na koje nailazimo pri pokušaju lokalizacije su dentinsko rame, mezijalna zakrivljenost te moguće kalcifikacije. Iz tog nam je razloga ključna pravilna priprema pristupnog kaviteta te korištenje suvremenih pomagala poput ultrazvučnih instrumenata, natrijevog hipoklorita, fluoresceina te CBCT-a prema potrebi. Instrumentacija MB2 kanala vrlo je zahtjevna i postoji velik rizik za lom instrumenta zbog tankih stijenki kanala te njegove izrazite zavijenosti. Upravo je zato vrlo važno korištenje pravilnog pristupa i tehnike kao balanced force ili crown-down pristup. Suvremeni sustavi (NiTi sustavi) omogućuju veću fleksibilnost te praćenje morfologije kanala kao i očuvanje integriteta njegovih stijenki. Ključ za uspješnu terapiju i očuvanje zuba čini kombinacija pravilne vizualizacije i pažljive instrumentacije MB2 kanala
Protetski vođena ortodoncija
No full textProtetski vođena ortodoncija predstavlja interdisciplinarni pristup koji kombinira ortodontsku i protetsku terapiju s ciljem postizanja optimalne funkcije, estetike i očuvanja tvrdih zubnih tkiva. Terapija se planira prema krajnjim protetskim ciljevima, čime se omogućuje minimalno invazivna preparacija i bolje pozicioniranje zubi za buduće nadomjestke. Protetski vođena ortodoncija uključuje pomoćnu ili sveobuhvatnu ortodontsku terapiju te postortodontsku protetsku terapiju. Pomoćna terapija usmjerena je na lokalizirane pomake poput uspravljanja zuba, forsiranog nicanja, poravnanja prednjih zuba i očuvanja prostora. Sveobuhvatna terapija obuhvaća složenije pomake potrebne kod gubitka više zubi, izraženog nedostatka tvrdog zubnog tkiva i rekonstrukcije vertikalne dimenzije zagriza. Ključna uloga digitalnih tehnologija, kao što su 3D skeniranje i softveri poput Invisalign Smile ArchitectTM, omogućuje precizno planiranje i predvidivost terapije. Estetski prihvatljive ortodontske naprave, osobito kod odraslih, uključuju prozirne alignere, keramičke bravice i lingvalnu ortodonciju. Nakon ortodontske faze slijedi protetska rehabilitacija koja uključuje digitalno ili analogno uzimanje otisaka, brušenje zuba te izradu trajnih nadomjestaka uz osiguranje retencije. Protetski vođena ortodoncija omogućuje bolju raspodjelu okluzijskih sila, višu biološku kompatibilnost i dugoročno stabilne rezultate u usporedbi s konzervativnom protetskom terapijom. Uspješnost terapije ovisi o kvalitetnoj dijagnostici, suradnji stručnog tima i motivaciji pacijenta, a koncept sve više postaje standard u rehabilitaciji odraslih pacijenata s kompleksnim dentalnim potrebama
METHODOLOGICAL AND THEORETICAL CHALLENGES IN TAX EXPENDITURE ANALYSES
No full textRad se usredotočuje na razne metodološke i teorijske izazove u analizi poreznih rashoda. Opsežna analiza poreznih rashoda vrlo je složen zadatak koji zahtijeva znatna sredstva i vrijeme, a dodatno je otežana nedostatkom prikladnih podataka. Osim toga, nepostojanje jedinstvene definicije poreznih rashoda otežava njihovu identifikaciju, analizu i usporedbe među zemljama. Najčešće se definiraju kao odstupanja od osnovnog ili referentnog poreznog sustava, a rezultat je njihova uvođenja smanjenje poreznih prihoda. Obično se javljaju u obliku poreznih olakšica, oslobođenja, izuzeća, odbitaka, odgoda, umanjenja osnovice ili samog poreza. Rad također razmatra pozitivne i negativne strane uvođenja te metodološke izazove prilikom analiza i evaluacija poreznih rashoda. Naglasak je na analizi troškova i troškovnoj efikasnosti, a osobito na različitim metodama izračuna poreznih rashoda i povezanih gubitaka poreznih prihoda, kao i na analizi izravnih i neizravnih učinaka poreznih rashoda. Zaključak ističe neke preporuke za reformu poreznih rashoda, radi unaprjeđenja njihove učinkovitosti, troškovne efikasnosti, odgovornije primjene i transparentnosti.The paper explores various methodological and theoretical challenges in tax expenditure analyses. A comprehensive analysis of tax expenditures is a complex task that requires significant resources and time, and is further complicated by the lack of appropriate data. In addition, the lack of a single definition of tax expenditures makes their identification, analysis, and cross-country comparison difficult. Tax expenditures are commonly defined as deviations from a benchmark tax system, and their introduction results in tax revenue losses. They usually take the form of tax relief, exemptions, exclusions, deductions, deferrals, reductions in the tax base, or reductions in the tax liability. This paper also examines advantages and disadvantages of tax expenditures, as well as the methodological challenges involved in the analysis and evaluation of tax expenditures. The focus is on the analysis of costs and cost-effectiveness, particularly on the different methods of calculating tax expenditures and the associated losses in tax revenue, as well as on the analysis of the direct and indirect effects of tax expenditures. The conclusion highlights several recommendations for the reform of tax expenditures, aimed at improving their effectiveness, cost-efficiency, more responsible implementation, and transparency
Corporate sustainability reporting in the context of regulatory adjustments and transitional exemptions
No full textRad analizira razvoj i prilagodbe regulatornog okvira korporativnog izvještavanja o održivosti u Europskoj uniji i Hrvatskoj, s posebnim naglaskom na odgode primjene obveza i prijelazna izuzeća uvedena nakon donošenja Direktive o korporativnom izvještavanju o održivosti (CSRD). Cilj rada jest ispitati u kojoj mjeri regulatorne izmjene pridonose usklađivanju ciljeva održive tranzicije s potrebom očuvanja konkurentnosti i smanjenja administrativnog opterećenja poduzetnika. U istraživanju se primjenjuju normativna i analitička metoda, uz pregled europskog i nacionalnog zakonodavstva te interpretaciju aktualnih zakonodavnih prijedloga. Rezultati ukazuju na postupno usklađivanje CSRD-a, Europskih standarda za izvještavanje o održivosti i Direktive o dužnoj pažnji za održivo poslovanje, uz jačanje proporcionalnosti i redefiniranje kruga obveznika. Empirijski pokazatelji, uključujući rezultate ESG ratinga za 2025. godinu i ESG akademije u razdoblju od 2022. do 2025. potvrđuju rastuću institucionalizaciju održivosti u poslovnoj praksi. Može se zaključiti kako se izvještavanje o održivosti transformira iz primarno regulatorne obveze u strateški instrument upravljanja rizicima i dugoročnom konkurentnošću.The paper analyzes the development and adaptation of the regulatory framework for corporate sustainability reporting in the European Union and Croatia, with particular emphasis on the postponement of the application of obligations and transitional exemptions introduced following the adoption of the Corporate Sustainability Reporting Directive (CSRD).The aim of the paper is to examine the extent to which regulatory amendments contribute to aligning the objectives of the sustainable transition with the need to preserve competitiveness and reduce the administrative burden on businesses. The research applies normative and analytical methods, including a review of European and national legislation as well as an interpretation of current legislative proposals. The results indicate a gradual alignment of the CSRD, the European Sustainability Reporting Standards, and the Corporate Sustainability Due Diligence Directive, alongside strengthened proportionality and a redefinition of the scope of obligated entities. Empirical indicators, including ESG rating results for 2025 and ESG Academy outcomes in the period from 2022 to 2025, confirm the growing institutionalization of sustainability in business practice. It is concluded that sustainability reporting is transforming from a primarily regulatory obligation into a strategic instrument for risk management and long-term competitiveness
SPATIAL VARIABILITY IN GROWTH AND CONDITION OF NILE TILAPIA Oreochromis niloticus LINKED TO POLLUTION GRADIENTS IN THE NILE RIVER, EGYPT
No full textU ovom istraživanju ispitivane su prostorne varijacije u rastu, faktoru kondicije, dobi i dugovječnosti populacija Oreochromis niloticus u različitim stupnjevima zagađenja u rijeci Nil, Asuan, Egipat. Usporedili smo referentnu lokaciju (Ferial, Lokacija I) s dvjema onečišćenim lokacijama: El-Sail Drain (Lokacija II) i Kom Ombo (Lokacija III). Uzorci vode i riba prikupljani su mjesečno od siječnja do prosinca 2021. godine radi analize fizikalno-kemijskih parametara, teških metala, dobne strukture, rasta i faktora kondicije. Rezultati su pokazali značajne prostorne razlike. Ribe s Lokacije I imale su najveći potencijal rasta, s asimptotskom duljinom (L∞) od 27,22 cm, koeficijentom rasta (K) od 0,17 godina⁻¹ i maksimalnom dobi od 13,5 godina. Za razliku od toga, populacije s Lokacije II i Lokacije III imale su smanjen rast (L∞ = 25,46, odnosno 24,52 cm), više K vrijednosti (0,19, odnosno 0,24 godina⁻¹) i kraći životni vijek (11,9, odnosno 9,2 godine). Iako je indeks rasta (Ø) bio sličan među lokacijama, godišnji prirasti duljine i faktori kondicije bili su značajno niži na onečišćenim lokacijama. Ovi nalazi pokazuju da degradacija okoliša, prvenstveno zbog industrijskih i kućanskih otpadnih voda, negativno utječe na rast i fiziološko stanje O. niloticus, što naglašava hitnu potrebu za poboljšanom kontrolom i strategijama upravljanja onečišćenjem u rijeci Nil.This study investigated spatial variations in growth, condition factor, age, and longevity of Oreochromis niloticus populations along a pollution gradient in the Nile River, Aswan, Egypt. We compared a reference site (Ferial, Site I) with two polluted sites: El-Sail Drain (Site II) and Kom Ombo (Site III). Water and fish samples were collected monthly from January to December 2021 to analyze physicochemical parameters, heavy metals, age structure, growth, and condition factor. The results revealed significant spatial disparities. Fish from Site I exhibited the highest growth potential, with an asymptotic length (L∞) of 27.22 cm, a growth coefficient (K) of 0.17 year⁻¹, and a maximum age of 13.5 years. In contrast, populations from Site II and Site III showed reduced growth (L∞ = 25.46 and 24.52 cm, respectively), higher K values (0.19 and 0.24 year-1, respectively), and shorter lifespans (11.9 and 9.2 years, respectively). Although the growth performance index (Ø) was similar among sites, annual length increments and condition factors were significantly lower at the polluted sites. These findings demonstrate that environmental degradation, primarily from industrial and domestic wastewater, adversely affects the somatic growth and physiological conditions of O. niloticus, highlighting the urgent need for enhanced pollution control and management strategies in the Nile River