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On-road vehicle emissions measurements show a significant reduction in black carbon and nitrogen oxide emissions in Euro 6c and 6d diesel-powered cars
No full textReal-world vehicle emissions measurement methods were developed to bridge the gap between laboratory tests and actual on-road emissions, including the variability in vehicles, drivers, and environmental conditions. The on-road chasing method is a cost-effective approach capable of capturing emissions from numerous vehicles. While it has been used extensively to measure truck emissions, it has not been applied systematically to diesel- and gasoline-powered cars. This study addresses that gap by comparing data from three on-road chasing campaigns conducted in 2011, 2017, and 2023 to evaluate the impact of emissions control technologies and regulatory policies on diesel- and gasoline-powered vehicles. Results show that diesel particulate filters (DPFs) reduce black carbon (BC) emission factors by 88 % compared to pre-DPF Euro 4 diesel-powered cars, while real driving emissions (RDE) regulations lower nitrogen oxide (NOx) emissions by 86 % relative to pre-RDE Euro 6b diesel-powered cars. This is the first study to apply the chasing method over a decade to a representative sample of European vehicles and to report real-world BC emission factors for cars compliant with Euro 5b–6d. Lorentz curve analysis reveals a growing influence of high-emission vehicles (“super-emitters”) on total fleet emissions, suggesting that targeting super-emitters could yield substantial reductions in traffic-related pollution. Despite methodological variability, the results are consistent across campaigns and align with major regulatory milestones, thus confirming the chasing method\u27s utility as a robust tool for super-emitter identification and fleet-wide emissions monitoring. By providing real-world evidence of regulatory effectiveness, this work supports scientific understanding and confidence in emissions policy
Bora wind studies in south-west Slovenia
No full textBora is a strong and gusty north-eastern wind, common in south-west regions of Slovenia, as well as along the Adriatic coast. The orography of south-west Slovenia gives a rise to the development of Bora, which is strongest in the Vipava valley. Intermittent behavior of Bora, related to variable strength, frequency and duration, has brought out scientific curiosity for decades. In the Vipava Valley, we study Bora by the analysis of experiments, as well as through numerical modeling. We perform high-resolution wind measurements, which are crucial for research of the Bora phenomenon. Events in the troposphere at the time of the Bora wind are also regularly monitored by using lidar, which detects vertical atmospheric structures
Vračanje v kaotičen in neodvisen prostor, ki ga skušam obvladati
No full textIntervju s pisateljico Katarina Gomboc Čeh. Dostopen je tukaj, drugače prosim za zaprt dostop do predstavitvene datoteke, kot v primeru intervjuja za LUD Literatura:
https://airbeletrina.si/primoz-mlacnik-vracanje-v-kaoticen-in-neodvisen-prostor-ki-ga-skusam-obvladati
Comparison of airborne in-situ with ground- and satellite- based LIDAR aerosol light extinction coefficient during JATAC/CAVA-AW 2021/2022 campaigns
No full textThe JATAC campaign in September 2021 and September 2022 on and above Cape Verde Islands was carried out with the main objective to calibrate and validate the ESA satellite Aeolus ALADIN lidar. The campaign also featured secondary scientific objectives related to climate change. Constraining remote sensing measurements with those provided by in-situ instrumentation is crucial for proper characterization and accurate description of the 3-D structure of the atmosphere.We present the results performed with an instrumented light aircraft (Advantic WT-10) set-up for in-situ aerosol measurements. Twenty-seven flights were conducted over the Atlantic Ocean at altitudes up to 3000 m above sea level during intense dust transport events. Simultaneous measurements with PollyXT, and eVe ground-based lidars took place, determining the vertical profiles of aerosol optical properties.The aerosol light extinction coefficient was determined at three different wavelengths as a combination of the absorption coefficients determined at 467, 529 and 653 nm using Continuous Light Absorption Photometers (CLAP) and the scattering coefficients 450, 525 and 635 nm measured with an Ecotech Aurora 4000 nephelometer. The particle size distributions above 0.3 µm diameter were measured with two Grimm 11-D Optical Particle Size Spectrometers (OPSS). Moreover, CO2 concentration, temperature, aircraft GPS position and altitude, air and ground speed were also measured.We compare the in-situ aircraft measurements of the aerosol extinction coefficients with the ALADIN lidar derived extinction coefficients, as well as with the ground-based eVe and PollyXT lidar extinction coefficients when measurements overlapped in space and time. The direct comparison is performed at 532 nm, where the PollyXT lidar wavelength closely matches that of the in-situ measurements. The comparisons at 355 nm are performed by extrapolating the in-situ aerosol extinction coefficients to match the measurement wavelengths of the PollyXT, eVe, and ALADIN lidar systems.In general we find an underestimation of the extinction coefficient obtained by lidars compared to the in-situ extinction coefficient. The slopes of Deming regression lines of ground-based lidars, PollyXT and eVe, against the in-situ measurements are characterised by values ranging from 0.74 to 0.94 and R2 between 0.74 and 0.89 at 355 nm. At the 532 nm, the slope of the regression characterizing the relationship between the PollyXT and in-situ measurements is 0.69, with an R2 value of 0.92 Comparison further suggests better agreement between ALADIN lidar and the in-situ measurements. Relationship described by fitting the Aeolus to in-situ data is characterised by the slope value 0.98 and R2 of 0.53 at 355 nm.The presented results show the importance of the comparison of the remote with in-situ measurements for the support of the research on evolution, dynamics, and predictability of tropical weather systems and provide input into and verification of the climate models
Selective photodetection at specific wavelengths in filterless single-channel field-effect transistors
No full textPhotodetectors are optoelectronic devices that output an electric signal when illuminated, with a wide range of uses in modern technologies from the fields of biomedical imaging to communications. However, further improving the sensitivity and functionality of these devices to achieve even broader applications would require further development of devices with selective detection capability over wide ranges of wavelengths. In this study, we present a novel photodetector capable of multiwavelength visible light detection using a blend of organic semiconductors and inorganic perovskites as active material. In this photofield-effect transistor (photoFET), the photogating effect of CsPbBr3 nanocrystals upon illumination below 520 nm triggers a large shift in threshold voltage while illumination over 600 nm results in an increase in current without threshold voltage shift. As a result, the device exhibits the capability to discriminate red and blue light, while being sensitive to the intensity of incident light within the visible spectrum. This innovative device opens the door to the development of single photodetector devices capable of recognizing multiple wavelengths and shows strong promise for increased photosensitivity due to the lack of power losses from filters. Furthermore, the combination of transistor operation and detection functions has strong promise for the development of reconfigurable and neuromorphic circuits
Carbonate formation during nickel hydroxide precipitation reduces pseudocapacitive performance
No full textNickel hydroxide (Ni(OH)2) is a promising pseudocapacitive material owing to its high theoretical capacitance and reversible Ni2+/Ni3+ redox activity. Here we demonstrate that carbonate incorporation during hydrothermal synthesis is the key structural factor limiting its electrochemical performance. Ni(OH)2 was prepared using hexamethylenetetramine (HMT) and urea at different synthesis temperatures, and carbonate incorporation was quantified by XRD, FTIR, Raman, TGA-MS, and CaCO3 precipitation. HMT-derived samples at a low temperature (80 °C) formed a turbostratic α-phase with interlayer water, delivering the highest specific capacitance (∼870 F g–1 at 1 A g–1) and excellent cycling stability (92–96% retention after 1000 cycles). In contrast, increasing the synthesis temperature promoted carbonate incorporation and crystallization into nickel carbonate hydroxide, reducing the interlayer spacing and surface area and increasing charge-transfer resistance. Urea-derived samples incorporated carbonate at all synthesis temperatures, yielding phases with capacitances an order of magnitude lower than those of HMT analogues. Electrochemical impedance spectroscopy confirmed that carbonate incorporation blocks redox-active sites and hinders ion/electron transport. These results provide a quantitative mechanistic understanding of how carbonate formation governs transition metal layered hydroxide performance, establishing guidelines for optimizing hydrothermal synthesis of pseudocapacitive electrodes
Audio fingerprinting method for Byzantine hymn recognition
No full textIn this work, a method for Byzantine hymn recognition is proposed utilizing an audio fingerprinting technique to generate speed and scale invariant fingerprints. The main steps of the process are the two-dimensional Fourier Transform (2DFT) and the calculation of a distance metric based on similarity matrices. The general concept is that by creating a database of fingerprints, it is possible to identify a query recording by extracting its fingerprints and compare them to the database. The method was tested by using a dataset of 351 different recordings of nine Byzantine hymns. Some key parameters of the process were evaluated in terms of accuracy and high scores, up to 99.44%, were achieved by introducing a statistical polling approach for the correct match selection
The role of logistics companies in promoting sustainable transport and reducing carbon emissions in supply chains
Get PDFThis thesis examines the role of logistics companies in advancing sustainable transport and reducing carbon emissions in supply chains. The motivation for the research is the significant environmental impact caused by logistics operations, coupled with the increasing demand for sustainable supply chain practices. The problem addressed is the lack of a comprehensive review on sustainable logistics practices, as existing literature focuses largely on isolated case studies rather than providing an overarching analysis of strategies across the sector. The aim of this thesis was to fill this gap by conducting a literature review to gain insights into the key challenges and opportunities in sustainable logistics. This topic is highly relevant given the growing pressure on logistics companies to adopt greener practices, yet there is limited comprehensive literature that synthesizes strategies and solutions available to address these environmental challenges. A systematic literature search was employed, classifying sources into different categories based on their focus on emission reduction strategies, transportation modes, and energy efficiency. The main results demonstrate the effectiveness of strategies such as investing in alternative fuel vehicles, optimizing routes through advanced algorithms, adopting cargo consolidation practices, fostering cross-industry collaboration, and implementing energy-efficient technologies in warehousing. The study concludes that although there are still obstacles to overcome, logistics companies possess considerable opportunities to reduce their environmental impact while maintaining efficiency in their operations. These findings offer valuable insights for companies seeking to enhance their environmental performance and contribute to the ongoing efforts toward sustainable supply chain management
Child’s perception of the world in Ivan Cankar’s novel Kuća Marije Pomoćnice The ward of our Lady of Mercy
No full textOvaj rad se zasniva na tumačenju infantilne percepcije sveta u Cankarevom romanu Kuća Marije pomoćnice koja je interpretativno interesantna stoga jer izneverava konvencionalni horizont očekivanja. Suštinska egzistencijalna pitanja poput života, smrti, slobode, te odnosa prema drugome i drugosti propuštena su kroz vizuru deteta, te je znakovito pratiti kako se pojam dečijeg razvija u romanu. S tim u vezi važno je napomenuti I uticaj porodičnog modela na formiranje ličnosti, pri čemu se u romanu može primetiti njegovo narušavanje I niz posledica koje takvo narušavanje izaziva kod dece, aktivirajući izrazito pesimistično poimanje sveta. Tema bolesti takođe će u radu zadobiti važno mesto u cilju rasvetljavanja infantilnog pogleda na svet.Cankar’s novel The Ward of Our Lady of Mercy published in 1904 represents an important step towards modern literature with indepth psychological dimensions of the characters as well as with a developed symbolic layer of a story about marginalized girls. Third person narrator guided by Malči gives the readers insight into the marginalized convent/hospital that functions by its internal logic that overcomes the convencional horizon of expectation. Cold and dark enterier of the hospital is inhabited by children which in a reader activates a string of associations related to the concepts of innocence, vitalism and joyfulness. However, semantic solutions brought by the novel conflict with given concepts. Therefore the reader encounters a whole array of children’s feelings, thoughts and conversations that aren’t inherent to them. That’s why this paper focuses on the naturalism heritage Cankar uses in this novel in order to try to motivate childs suffering and disdain towards life and its positive values related to sins of their parents. On the other hand the religious layer of the novel contributes to the constructing of the victim motif, that fits into expiation narrative and the hope for the better life after death