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PRELIMINARNO ISTRAŽIVANJE UTJECAJA ALTERACIJE NA SVOJSTVA USITNJAVANJA ANDEZITA IZ KAMENOLOMA TÁLLYA I RECSK (MAĐARSKA)
No full textThis preliminary study investigates the influence of post-magmatic alteration on the breakage behaviour of andesitic rocks during comminution, with particular emphasis on the Chemical Index of Alteration (CIA) and smectite content. Six representative samples from two Hungarian quarries (Recsk and Tállya) exhibiting broadly similar mineralogical and textural properties but varying degrees of alteration were subjected to single particle breakage tests across multiple size fractions. Although the limited dataset does not allow for broad generalisation, the results provide a first indication that increased CIA values and higher smectite contents are associated with greater fragmentation susceptibility, as reflected by elevated A×b parameters. The study demonstrates that alteration indices can provide valuable predictive information on breakage response in andesitic rocks. These findings suggest the importance of integrating alteration metrics alongside traditional mineralogical and textural parameters when evaluating the breakage behaviour of andesitic rocks for aggregates production. While smectite quantification highlights the role of secondary phyllosilicate minerals in reducing the strength of andesitic rocks, CIA offers a more broadly applicable measure of alteration intensity that may be transferable across different volcanic contexts. The results are presented as a case study that highlights the potential of CIA and smectite quantification as predictive tools, while acknowledging the need for further research with larger datasets to confirm these trends.Ova preliminarna studija istražuje utjecaj postmagmatske alteracije na ponašanje andezitnih stijena tijekom usitnjavanja s posebnim naglaskom na kemijski indeks alteracije (CIA) i sadržaj smektita. Šest reprezentativnih uzoraka iz dvaju mađarskih kamenoloma (Recsk i Tállya), koji pokazuju uglavnom slična mineralna i teksturna svojstva, ali različite stupnjeve alteracije, podvrgnuto je ispitivanjima lomljenja pojedinačnih čestica u više granulometrijskih frakcija. Iako ograničen broj podataka ne omogućuje široke generalizacije, rezultati pružaju početne pokazatelje da su viši CIA indeksi i veći sadržaji smektita povezani s povećanom sklonošću fragmentaciji, što se očituje kroz povišene A×b parametre. Studija pokazuje da indeksi alteracije mogu pružiti vrijedne prediktivne informacije o odgovoru andezita na usitnjavanje. Dobiveni rezultati upućuju na važnost uključivanja parametara alteracije uz tradicionalne mineralne i teksturne karakteristike prilikom procjene ponašanja andezitnih stijena u proizvodnji agregata. Kvantifikacija smektita naglašava ulogu sekundarnih filosilikatnih minerala u smanjenju čvrstoće andezitnih stijena, dok CIA predstavlja šire primjenjivu mjeru intenziteta alteracije koja se može primijeniti u različitim vulkanskim kontekstima. Rezultati se predstavljaju kao studija slučaja koja ističe potencijal CIA indeksa i kvantifikacije smektita kao alata za procjenu, uz naglasak na potrebu za dodatnim istraživanjima s većim brojem uzoraka radi potvrde uočenih trendova
Cardiac functional recovery after acute coronary syndrome: a comparison between smokers and non-smokers
No full textDefending Social and Ecological Space: A Critical Analysis of the Documentary Film Dragon for Sale and Premium Tourism on Komodo Island, Indonesia
No full textThis research examines the controversy surrounding premium tourism development in Labuan Bajo. It specifically focuses on the eviction of the Ata Modo community from Komodo Island, as depicted in the documentary Dragon for Sale. The documentary is both a cinematic work and a journalistic report that documents real-life socio-political issues. Using Teun A. van Dijk's Critical Discourse Analysis (CDA), the study examines the tension between government-driven tourism policies and the rights of local communities. It delves into the government's plans for tourism development around Komodo dragons, highlighting the adverse impacts on local communities, including displacement and loss of cultural identity. The findings underscore the conflict and deprivation of community rights, emphasising the exclusion of local voices from decision-making and calling for more inclusive, equitable, and sustainable tourism policies
Privacy Integrity-Aware Blockchain Communication in Federated Edge Learning Platform
No full textThe blockchain architecture offers transparent security mechanisms in a decentralized manner; due to this, it has attained increasing growth in a federated edge-server learning environment. In federated learning, the data model is executed in multiple edge servers in a collaborative manner, increasing users’ privacy and data-integrity breach because of single point failure attack in the main computational server. Blockchain employing a rewarding mechanism in federated edge-learning platform aids the model to overcome single-point aggregation failure. However, the current method failed to identify selfish and baized workers; further, reaching global consensus model to assure privacy-integrity in blockchain-enabled federated edge-server is difficult. This paper presents privacy-integrity-aware blockchain communication (PIABC) in federated edge-server learning platform. The PIABC model is very effective in comparison with existing blockchain-privacy preserving schemes for identifying the correctly aggregated packets and eliminating malicious packets within the federated edge-server learning platform
Dual-Surface Engineering of Fe3O4 Magnetic Nanoparticles: Enhanced Magnetorheological Performance and Tribological Mechanisms
No full textMagnetic fluids are smart materials that fall under the category of magnetic materials and possess the property of fluidity. Nevertheless, conventional modifications using a monolayer surfactant are limited due to poor thermal stability and insufficient nanoparticle-carrier fluid compatibility. The synthesis of Fe3O4 nanoparticles via co-precipitation, is followed by a unique bilayer surface coating of oleic acid and boron-modified high molecular weight succinimide. The nanoparticles' characterization result indicates that as the nanoparticles were modified their diameter decreased from 13.66 nm to 11.39 nm. Their structure remained as cubic spinel structure with saturation magnetization of 61.48 emu/g. Analysis of FT-IR spectra confirmed that OA is anchored to the surface of the particles through the formation of Fe-OOC-R bonds. Hence, BSI will form a stable interfacial layer in this case. Rheological studies have shown a strong magnetoviscous effect in the magnetic field of 200 kA/m at 263 K which was suppressed when the temperature was raised to 313 K. According to tribological tests, the use of 4.5 wt% tungsten dialkyldithiocarbamate (WTDC) reduced friction, as the lowest CoF is indicated to occur at a value of N Load = 35 N at 6 Hz. Consequently, the technique presented herein will be used to create high-performance magnetic fluids for applications such as aerospace sealing and MEMS lubrication
Research on Intelligent Monitoring of E-Government Using LLM, RAG, and Hybrid Retrieval Technologies
No full textLarge language models are one of the core research contents of natural language processing and have been widely applied in many fields including government affairs. The problems that need to be solved in the research of large language models for government affairs are proposed, namely, data multimodality, correctly facing the trend of "model as a service", emphasizing high data security, and clarifying the boundaries of responsibility. In addition, the technical path for the research of large language models for government affairs has also been proposed. Then, the feasibility of the large language model in the process of industrial collaborative emergency preparedness is analyzed. The P-Tuning method is adopted for model fine-tuning. A local knowledge base is constructed based on the question-answering data related to the intelligent monitoring events of e-government. The content generated by the model is standardized, and the LangChain architecture is utilized to build the industrial collaborative emergency question-answering system. Based on the large model knowledge base, a hybrid retrieval dual-tower model was proposed. The model integrates the multi-path recall strategy to ensure the comprehensive retrieval results. The multi-level ranking of the retrieval results was achieved through the adoption of hybrid retrieval. The correlation of the retrieval results has been significantly improved. Further, the optimized information and the original query are input into the large language model to generate accurate answers. Experiments show that this method significantly improves the accuracy of retrieval
Obtaining of Thermal, Vibration, Air Flow Speed and Performance Analysis of Stator Fin Failure of Three Phase Squirrel Cage Induction Motor
No full textUnder normal operating conditions, induction motors reach a higher temperature value than the initial operating temperature. The higher this temperature value is, the more the losses in the motor increase, negatively affecting the performance of the motor. The increased heat needs to be removed from the motor. There are several ways to do this, the most commonly used of which are the use of fans, fins in the stator frame and fins in the rotor end ring. In this study, the cooling fins in the stator frame of an induction motor were spiraled to create a faulty motor frame. The focus of the study is to experimentally obtain the effects of thermal analysis on the faulty motor body. In addition, performance analyses, vibration analyses and air flow analyses of the motor were performed. These four analyses obtained from the faulty motor were compared with the healthy motor. In order to obtain the data, the motor was tested in no-load, short circuit and loaded operation. The data obtained showed that the temperature values in the faulty motor casing were 6.22% higher in short-circuit operation and 7.95% higher in loaded operation compared to the healthy motor, and accordingly, the performance was adversely affected. The absence of stator fins in the faulty motor caused an asymmetrical distribution of airflow and the difference between inlet and outlet airflow speed decreased by 43%. In addition, it was determined that the faulty motor operated with 1.5-2 times more vibration
Research, Development, and Innovation in Croatia (Part Two) – National Innovation System and Smart Specialisation Strategy until 2029
No full textInovacije su jedan od glavnih čimbenika konkurentnosti gospodarstva i napretka društva. Iako Republika Hrvatska ulaže u istraživanje, razvoj i inovacije (IRI) te je u tom području napredovala u posljednjih desetak godina, posebice zahvaljujući sredstvima iz fondova Europske unije (EU), još se uvijek nalazi na začelju inovacijskih ljestvica EU-a, kao i razvijenih zemalja globalno. Stoga je potrebno dugoročno, dobro osmišljeno i ciljano ulagati u IRI da bi se u tom području u Hrvatskoj postigao značajniji rast i napredak.
Ovaj rad, u kontekstu trenutačnog strateškog okvira EU-a u području IRI-ja, donosi prikaz nove Strategije pametne specijalizacije (S3) do 2029., uspoređuje ju s prvom hrvatskom S3 2016.–2020. te procjenjuje implementaciju preporuka Svjetske banke i Europske komisije u tekst S3 do 2029. U fokusu rada su promjene koje bi nova S3 do 2029. trebala unijeti u nacionalni inovacijski sustav (NIS) i njegovo funkcioniranje.
Nakon dugotrajne, no ipak uspješne uspostave, daljnji razvoj NIS-a potencijalno bi trebao uključivati barem sljedeće: smanjenje kompleksnosti i fragmentiranosti sustava; centraliziranije, učinkovitije i djelotvornije upravljanje svim njegovim dijelovima; osiguravanje kontinuiteta funkcioniranja njegovih tijela kao i kontinuiteta podrške procesu poduzetničkog otkrivanja; jačanje institucijskih kapaciteta i suradnje u području IRI-ja među nadležnim državnim institucijama na svim razinama; bolju komunikaciju i kontinuiranu edukaciju svih dionika te daljnje unaprjeđenje suradnje među njima (posebice znanstveno-istraživačke zajednice i poslovnog sektora); eksperimentiranje, fleksibilnost i učenje na pogreškama u provedbi strategija, politika i programa; daljnji razvoj svijesti o važnosti inovacija za gospodarstvo i društvo; kontinuitet podrške inovacijama općenito (uključujući financiranje). Stoga je ključno čim prije ponovno uspostaviti operativno funkcioniranje tijela NIS-a i obnoviti procese poduzetničkog otkrivanja koji ne funkcioniraju već više od tri godine. Naime, ukupni hrvatski rezultati u području IRI-ja i njihov transformacijski učinak na gospodarstvo i društvo ovise, među ostalim, o uspješnosti implementacije S3 do 2029. (trenutačno jedinog strateškog dokumenta u području IRI-ja u Hrvatskoj), o radu Nacionalnog inovacijskog vijeća (tijela za upravljanje politikama IRI-ja, uključujući S3, i krovnog tijela NIS-a) i funkcioniranju cjelokupnog NIS-a, posebice procesa poduzetničkog otkrivanja.The competitiveness of economy and the progress of society greatly depend on innovation. Despite the investments made (largely from EU funds) to enhance research, development and innovation (RDI), and the advancement achieved over the past ten years, the EU and global innovation rankings of Croatia remain low. To move forward long-term, well designed and targeted investments in RDI are required.
This paper aims to provide an overview of the Croatian Smart Specialisation Strategy (S3) until 2029 in light of the current EU RDI strategic framework. A comparison is made with the S3 2016–2020, and the implementation of the World Bank and European Commission recommendations in the text of S3 until 2029 is assessed. The focus is on the changes to the national innovation system (NIS), as envisaged by the S3 until 2029, and on its overall functioning. To advance the NIS, at least the following should be considered: reducing system complexity and fragmentation; establishing a more centralised, effective, and efficient management of its overall structure; ensuring the continuous operation of its bodies and support for the entrepreneurial discovery process (EDP); strengthening institutional capacities and collaboration in the field of RDI among relevant government institutions at all levels; ensuring continuous education and improved communication among all stakeholders, and further enhancing cooperation – especially between business and science; allowing for experimentation, flexibility, and learning from mistakes; raising awareness of the importance of innovation for the country’s economy and society; and providing continuous support for innovation in general, including funding. Therefore, it is crucial to urgently re-establish operation of the NIS bodies and to revitalise the EDP, as they have not been functioning for more than three years. Namely, Croatia’s overall RDI performance and its transformational impact on the economy and society depend, among other factors, on the successful implementation of the S3 until 2029 (currently the only strategic RDI document in Croatia), on the functioning of the National Innovation Council – the body responsible for managing RDI policies, including the S3, and serving as the NIS umbrella body, and on the effective operation of the overall NIS, especially the EDP
Maternal serum steroid hormones in vaginal delivery and caesarean section
No full textIntroduction: The hormonal interplay between the mother and the fetal-placental unit may influence the mode of delivery. This study aimed to investigate the association between maternal peripartal serum concentrations of sex hormone-binding globulin (SHBG) and 10 steroid hormones with delivery outcomes.
Materials and methods: This observational study included 171 healthy pregnant women with spontaneous onset of labor: 117 had vaginal delivery and 54 underwent urgent cesarean section (C-section). Serum concentrations of aldosterone, androstenedione, cortisol, cortisone, corticosterone, dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), 17-hydroxyprogesterone, progesterone, and total testosterone were determined by liquid chromatography–tandem mass spectrometry (LC-MS/MS), while free testosterone was calculated. Sex hormone-binding globulin was measured by chemiluminescent microparticle immunoassay. Group differences were tested with the Mann-Whitney U test, and associations with delivery mode were assessed by logistic regression and receiver operating characteristic (ROC) analysis.
Results: Compared with the vaginal delivery group, women who underwent urgent C-section had significantly lower serum concentrations of SHBG, corticosterone, cortisol, aldosterone, progesterone, 17-hydroxyprogesterone, DHEA, DHEAS, and free testosterone (all P 0.9 nmol/L predicted vaginal delivery with AUC 0.874, sensitivity 88%, and specificity 77%.
Conclusions: Low maternal aldosterone concentrations showed the strongest association with urgent C-section, suggesting that aldosterone may play a protective role in successful vaginal delivery
CAN Bus Joystick Data to Assess Operator Workload: A Forwarder Loading Case Study
Get PDFModern forest harvesting machinery generate an abundance of underutilised data in their control systems. The Controller Area Network (CAN) bus data stream offers the opportunity to investigate the operation of the machinery in detail while in real-world harvesting scenarios. This study uses CAN data to assess a component of operator workload in forwarder operations, by introducing a method to interpret forwarder joystick movements. The data was captured in a clearfell logging operation case study in Canterbury, New Zealand. The joystick data was then analysed to determine the time and number of operator input movements per load cycle (»grab«) totalling 418 grabs. This, combined with video analysis, identified independent variables that describe the grab cycle such as time of day, number of logs per grab, log grade, and the activities of »pencilling« (vertical drop of logs in grab to align large ends) and »dropping« (releasing logs from the grab before loading). Factors that significantly affected the operators' time taken to complete the grab and the number of required joystick movements included number of logs, pencilling and dropping. For example, the average load cycle was 18-seconds for four logs, and this increased by 6.1-seconds and 14.4-seconds per grab when pencilling or dropping, respectively. Average total joystick movements were ~108 per grab. This case study demonstrated that CAN bus data can be used to improve our understanding of the operation of harvesting equipment such as forwarders. An example use of the result is to share and compare this with the harvester operator (who crosscuts and sets out the logs for forwarder-collection) as the need for pencilling and dropping is a consequence of misalignment or debris caught in the piles. The method used also presents an opportunity for human factors research, particularly in operator fatigue management and training through the measurement of joystick movements with a genuine possibility of real-time performance feedback