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ISTRAŽIVANJE GEOTERMALNOGA SUSTAVA KORIŠTENJEM NAPREDNE OBRADE I INVERZIJE GRAVITACIJSKIH PODATAKA U NEVULKANSKOME GEOTERMALNOM POLJU LAINEA, INDONEZIJA
No full textIndonesia is a country that has abundant geothermal resources. The purpose of this research is to investigate the geothermal system in the Lainea non-volcanic geothermal field, Southeast Sulawesi Province, Indonesia. This includes (i) estimating the geothermal reservoir basins, cap rocks, and basements; (ii) estimating the heat source; and (iii) evaluating the subsurface faults. The first two objectives were achieved by using the improved structural gravity inversion. The third objective was achieved by using advanced processing techniques, namely 3-D Euler deconvolution, tilt angle of horizontal gradient (TAHG), and fast sigmoid edge detection (FSED). Inversion of gravity data exhibits the reservoir basins that are located at depths from 600 m to 900 m with a density range of 2865 ≤ ρ < 2942 kg/m³. Several rock blocks with densities ranging from 2608 to 2865 kg/m³ function as caprock. The caprock is located at depths ranging from several tens of meters to 1000 m. The basement underlying the reservoir rock is the integration of rock layers with densities of 2948 ≤ ρ < 3045 kg/m³ and 3046 ≤ ρ ≤ 3122 kg/m³. The upper boundary of the basement is located at a depth of several ten meters to 1500 m below sea level. Intrusive plutonic rocks with maximum density of 3174 kg/m³ are located at depths ranging from 1500 m to more than 3000 m. The TAHG and FSED demonstrate the presence of subsurface faults with northwest-southeast and southwest-northeast trends. Euler deconvolution results support the fault model of the TAHG and FSED.Indonezija je zemlja koja ima obilne geotermalne resurse. Svrha je ovoga istraživanja ispitati geotermalni sustav u nevulkanskome geotermalnom polju Lainea, pokrajina Jugoistočni Sulawesi, Indonezija. To uključuje (i) procjenu geotermalnih bazena rezervoara, krovnih i temeljnih stijena, (ii) procjenu izvora topline i (iii) procjenu podzemnih rasjeda. Prva dva cilja postignuta su korištenjem poboljšane strukturne gravitacijske inverzije. Treći cilj postignut je korištenjem naprednih tehnika obrade, i to 3D Eulerove dekonvolucije, kuta nagiba horizontalnoga gradijenta (TAHG) i brze detekcije rubova sigmoidom (FSED). Inverzija gravitacijskih podataka pokazuje bazene rezervoara koji se nalaze na dubinama od 600 m do 900 m s rasponom gustoće od 2865 ≤ ρ < 2942 kg/m³. Nekoliko blokova stijena s gustoćama u rasponu od 2608 do 2865 kg/m³ funkcionira kao krovna stijena. Krovna stijena nalazi se na dubinama u rasponu od nekoliko desetaka metara do 1000 m. Temeljna stijena ispod stijene rezervoara jest integracija slojeva stijena s gustoćama od 2948 ≤ ρ < 3045 kg/m³ i 3046 ≤ ρ ≤ 3122 kg/m³. Gornja granica bazne stijene nalazi se na dubini od nekoliko desetaka metara do 1500 m ispod razine mora. Intruzivne plutonske stijene s maksimalnom gustoćom od 3174 kg/m³ nalaze se na dubinama u rasponu od 1500 m do više od 3000 m. TAHG i FSED pokazuju prisutnost podzemnih rasjeda sa smjerovima pružanja sjeverozapad-jugoistok i jugozapad-sjeveroistok. Rezultati Eulerove dekonvolucije podržavaju model rasjeda TAHG i FSED
A Systematic Review of Timber Tracking and Tracing in Forest and Timber Industry Supply Chain: An Analysis of Subject Areas, Objectives, and Characteristics
Full text linkIn the past decades, a considerable body of literature has emerged on timber tracking and tracing in the forest and timber industry supply chain. Therefore, a systematic literature review was conducted using an established method (»PRISMA«). To help define the relevance of timber tracking and tracing, this review addresses the subject areas, objectives and characteristics from scientific studies conducted over the past 25 years. In total 213 papers were included in the qualitative synthesis of the subject areas and objectives, with a 160 of those included in the characteristics synthesis to analyse comparable publication contents.
This study demonstrates the rationale behind the research efforts in the field of timber tracking and tracing. The results showed that the main key objectives were to combat illegal logging and trade, provide sustainable forest management, enable tracking and tracing, enhance efficiency, ensure legal compliance, determine the origin of timber and to identify species. The characteristics of the analysis methods used showed that genetic methods, physical chemistry methods, image methods, geomatics, certification, Radio-Frequency Identification (RFID) and smart technologies and software applications were most common. Most research activities were conducted in Asia and Europe. The majority of tracking and tracing methods were found to be highly practical. The application along supply chain dominated because of the high number of publications in genetic methods where a comprehensive application is possible. Furthermore, the forest, harvesting, and manufacturing were identified as core application areas. Most studies lacked an economic evaluation of the developed solutions, which is a crucial aspect to consider for future successful implementation. The number of tree/wood species involved was notably extensive with a considerable diversity observed across continents. It will be essential that future research incorporates new technologies such as artificial intelligence (AI) that is currently emerging in the field of timber traceability. This can help achieve the identified objectives and address existing and future challenges through the self-learning property of AI
Can student attitudes toward immigration be changed? Evidence from a survey experiment in Croatia
Full text linkExtreme right-wing parties are increasing in polls around Europe, largely fueled by an anti-migrant rhetoric. Political economy literature points to, on average, net positive effects that migrants bring to the economy, but the balance on the political market is more worrisome. For a small open economy, overly dependent on tourism, whose population reduced by more than 1 million in the last 30 years, the question of successful integration of migrants represents a first order condition of public policy. Thus the research question set in this paper is how to change attitudes on immigration among students in the Croatian society. Our approach is based on an experiment within a survey and it is tested on a sample of 1,450 students from five university cities in Croatia (Osijek, Pula, Rijeka, Split and Zagreb). Results indicate that there is a sizeable and statistically significant effect for the treated groups vis-a-vis their attitudes on the effect that migrants have on the labour market, social security system, overall safety and the economic development of Croatia
Claudins proteins in brain tumors: expression patterns and therapeutic target
No full textTight junctions (TJs) are essential for preserving cell polarity and controlling permeability. It has been disclosed that TJ proteins, especially specific claudins (CLDNs), are linked to inflammation and contribute to the emergence of diverse cancers, including brain malignancies. Aggressive gliomas, including glioblastoma multiforme (GBM), remain among the most common and deadly central nervous system (CNS) tumors worldwide, despite considerable advances in diagnostic and therapeutic approaches. These types of tumors are characterized by high rates of recurrence and metastasis, resulting in poor outcomes and prognosis. The pathophysiology of brain cancer is closely linked to CLDNs, as these specific proteins play critical roles in tumor cell proliferation, invasion, and disruption of the blood-brain barrier (BBB). Some studies reported the potential role of CLDNs in glioma progression and other neurological disorders. The purpose of this review is to highlight the significance of CLDNs in CNS tumors, especially their participation in the formation of malignant gliomas. Additionally, the diagnostic and prognostic importance of selected CLDNs has been assessed. Selected CLDNs, such as CLDN3 and CLDN4 promote GBM growth, proliferation and migration. Moreover, overexpression of CLDN3 support progression and metastasis of these malignancies, while reduced expression of CLDN1 and CLDN5 is observed in advanced gliomas. Presented results suggest that CLDNs may serve as biomarkers for diagnosis and prognosis as well as therapeutic targets in CNS tumors. Further investigation is essential to clarify their clinical relevance and therapeutic potential
Sentivolve: Utilizing FastText, CRF, HAN, and Random Forests for Enhanced Sentiment Analysis
No full textThe objective of this study is to enhance sentiment analysis through an integrative approach termed Sentivolve, which combines FastText embeddings, Conditional Random Fields (CRF), Hierarchical Attention Networks (HAN), and Random Forests (RF). The system aims to improve sentiment classification by leveraging advanced feature extraction, sequence modeling, attention mechanisms, and ensemble learning. FastText captures subword information for better text representation; CRF models sequential dependencies; HAN highlights key textual elements using a hierarchical attention structure; and Random Forests aggregate predictions to ensure consistent sentiment classification. Experimental results demonstrate that Sentivolve outperforms traditional models in both accuracy and generalizability. This integrated approach provides an effective solution for sentiment analysis, especially in handling diverse and complex text data
Effect of Crosswind on Drag and Lift Variations during Mixed-Vehicle Overtaking Manoeuvres: A CFD Approach
No full textA CFD-based analysis is carried out in this study to examine time-dependent aerodynamic effects during highway overtaking manoeuvres, with a primary focus on truck-truck interactions under crosswind conditions. Using ANSYS Fluent and unsteady Reynolds-Averaged Navier-Stokes (RANS) simulations, the time-resolved aerodynamic behaviour of a truck being overtaken by an identical vehicle is investigated in detail. A secondary case involving a passenger car overtaking the truck is also examined for comparative purposes. The analysis concentrates on the evolution of the drag and lift coefficients of the overtaken truck throughout the overtaking process. Results indicate that truck-truck interactions produce stronger aerodynamic disturbances, with greater fluctuations in drag and lift compared to the car-truck scenario. These effects are strongly dependent on vehicle spacing and relative positioning. The findings highlight the critical role of transient aerodynamic loading in the design and operation of heavy-duty vehicles, particularly in mixed traffic environments and crosswind-prone areas. This research advances the understanding of real-world aerodynamic interactions, with implications for fuel efficiency, dynamic stability, and highway safety
In-depth Analysis of the Control Unit for Multiple Voltage Rails to Drive a Variety of ICs
No full textGenerating a negative output voltage rail from a positive input voltage is possible by reconfiguring an ordinary buck regulator into an inverting buck-boost (IBB) topology. Rather than operating considerations such as voltage and current stresses, the main challenge associated with this transformation arises from differences in the small-signal closed-loop characteristics. The most critical distinction is the presence of a right-half-plane (RHP) zero in the control-to-output transfer function of the IBB, which introduces non-minimum-phase behaviour, reduces the achievable phase margin, and may lead to instability and poor load transient response. For conventional PI controllers, the buck and IBB converters resulted in settling times of 5.0 ms and 6.8 ms, with overshoots of 13.65% and 8.46%, respectively, thus demonstrating the performance limitations of fixed-gain designs. As a solution, an auto-tuned PI controller with adaptive features has been proposed, which operates effectively in both the buck and IBB topologies. The proposed scheme achieves a significantly faster settling time of 2.27 ms with overshoot and undershoot below 2%, thereby ensuring superior robustness and dynamic performance compared to conventional approaches
Teachers' Attitudes Towards the Quality and Prospects of Architectural Education in the Republic of Serbia
No full textThis study explores teachers' attitudes toward the quality and future prospects of architectural education in the Republic of Serbia. Based on a survey conducted among 82 educators from nine higher education institutions, the research examines the influence of five key predictors: student motivation, frequency of communication with students, perceived student appreciation, typical student behaviour, and interfaculty collaboration. Descriptive statistics and multiple regression analyses were applied to determine the most significant predictors of teachers' perceptions. The results show that student motivation and teachers' sense of being valued significantly contribute to positive perceptions of teaching quality. In contrast, typical student behaviour and interfaculty collaboration did not have a statistically significant impact. Regarding future perspectives, student motivation again emerged as the strongest predictor, while more frequent communication with students and observed student insecurity negatively affected outlooks on educational development. The findings highlight the complexity of teaching architectural design and underline the importance of fostering student engagement, strengthening mentorship, and adapting instructional strategies. This research contributes to a deeper understanding of the dynamics shaping architectural education and offers recommendations for enhancing teaching practices both in local and global contexts
HFDDLap: High-Low Frequency Differentiation Dynamic Laplacian Pyramid Network for Image Super-Resolution
No full textExisting single image super-resolution (SR) algorithms based on convolution neural networks (CNNs) have achieved usable visual results. However, they often encounter artifacts and blurring, particularly at large scaling factors (e.g., 4×, 8×), due to significant loss of high-frequency information. To address these challenges, we propose a novel high-low frequency differentiation dynamic Laplacian pyramid network (HFDDLap). Our approach introduces a learnable high-low frequency differentiation convolution (HLC) within high-low frequency differentiation residual channel attention blocks (HL-RCAB) to effectively capture and differentiate high- and low-frequency components, enhancing detail preservation. Additionally, we employ a dynamic deconvolution (DDC) that adaptively generates upsampling kernels based on input features, improving reconstruction accuracy by reducing feature distortion. Extensive experiments on 4× and 8× SR demonstrate that our proposed method effectively reconstructs edge details, produces satisfactory SR results and outperforms some state-of-the-art (SOTA) methods in terms of evaluation metrics
The Role of Forests in Hydrological Processes
No full textRad obrađuje interdisciplinarnu prirodu hidrologije, naglašavajući njezinu ključnu ulogu u razumijevanju i rješavanju problema povezanih s vodom. Voda se ističe kao osnovni preduvjet života, razvoja društava i ekosustava, ali i kao izvor potencijalnih prijetnji u obliku poplava i suša. Klimatske promjene dodatno pojačavaju te rizike, zbog čega je nužno bolje upravljati vodnim resursima. Iznesene su različite podjele hidrologije (prema komponentama hidrološkog ciklusa, metodama istraživanja, primjeni i prostornoj skali) te je istaknuta pojava novih područja poput ekohidrologije i socio-hidrologije. One integriraju prirodne i društvene procese, istražujući kako interakcija vode, ekosustava i ljudi oblikuje okoliš i društveni razvoj. Poseban naglasak stavljen je na hidrologiju šuma. Šume svojim procesima intercepcije, infiltracije, transpiracije i smanjenja površinskog otjecanja značajno utječu na vodnu bilancu, regulaciju hidroloških ekstrema, ublažavanje erozije, zaštitu od poplava i očuvanje kvalitete pitke vode. Istraživanja pokazuju da šume smanjuju varijabilnost padalina, stabiliziraju klimu i djeluju kao prirodni rezervoari i filteri vode. Istovremeno, deforestacija povećava otjecanje i eroziju, dok pošumljavanje može privremeno smanjiti raspoloživu vodu zbog visoke evapotranspiracije mladih šuma. Optimalni učinci ovise o klimi, tipu šume i prostornoj skali. Naglašava se potreba za integriranim pristupom gospodarenju šumama i vodama budući da utjecaji šuma na vodne resurse nisu univerzalno pozitivni ili negativni, već ovise o lokalnim uvjetima. Budući razvoj hidrologije šuma zahtijeva interdisciplinarnost, dugoročne podatke i povezivanje znanstvenih istraživanja s praktičnim upravljanjem ekosustavima u uvjetima klimatskih promjena.The paper discusses the interdisciplinary nature of hydrology, emphasizing its key role in understanding and solving water-related problems. Water stands out as a basic prerequisite for life, the development of societies and ecosystems, but also as a source of potential threats in the form of floods and droughts. Climate change further intensifies these risks, which is why better water resource management is necessary. Different divisions of hydrology are presented (according to components of the hydrological cycle, research methods, applications and spatial scale) and the emergence of new fields such as ecohydrology and socio-hydrology is highlighted. They integrate natural and social processes into hydrology, exploring how the interaction of water, ecosystems and people shapes the environment and social development. Special emphasis is placed on forest hydrology. Forests, through their processes of interception, infiltration, transpiration and reduction of surface runoff, significantly affect the water balance, the regulation of hydrological extremes, erosion mitigation, flood protection and preservation of drinking water quality. Research shows that forests reduce rainfall variability, stabilize the climate and act as natural reservoirs and filters for water. At the same time, deforestation increases runoff and erosion, while afforestation can temporarily reduce water availability due to high evapotranspiration of young forests. Optimal effects depend on climate, forest type and spatial scale. The need for an integrated approach to forest and water management is emphasized, since the impacts of forests on water resources are not universally positive or negative, but depend on local conditions. Future development of forest hydrology requires interdisciplinarity, long-term data and linking scientific research with practical ecosystem management in the context of climate change