75 research outputs found
CLASSIFICATION OF ELECTRICITY CONSUMERS USING ARTIFICIAL NEURAL NETWORKS
This paper explains the process of using neural networks, as one of numerous data mining techniques, for the classification of electricity consumers. The processed data comprised more than a million recordings of electricity consumption for 21,643 consumers over the period of four years and eight months. Using a data subset (70% of the entire dataset), the network was trained for the classification of consumers according to the type of the electric meter they possess (single-rate or dual-rate) and the zone they live in (city or village). The network input data in both cases included: consumer code, reading period from-to, current and previous meter reading for both low and high tariff, dual and single rate tariff consumption for that period and their total amount, as independent variables, whereas the network output comprised dependent variable classes (zone or type of electric meter). The results show that a network created in this way can be trained so well that it achieves high precision when evaluated using the test dataset. Using the available recordings about electricity consumption, the type of the electric meter consumers possess and the zone they live in can be predicted with the accuracy of 77% and 82%, respectively. These findings can provide the basis for further research using other data mining techniques
Selecting the Flexible Last-Mile Delivery Models Using Multicriteria Decision-Making
Postal service providers can reorganise the last-mile delivery process within the scope of universal service and apply some of the flexible models for the organisation of the delivery. In this paper, the question of the selection of Flexible Last-Mile Delivery Models (FLMDMs) is treated using multicriteria decision-making. We have identified four different sustainable last-mile delivery models with an emphasis on the number of delivery workers. One postal service provider from Europe was selected, where the proposed FLMDMs were tested. The proposed last-mile delivery models are ranked using Multiple Criteria Decision Analysis (MCDA) techniques. In this context, MCDA techniques are used to make a comparative assessment of alternatives. The obtained results suggest the AB delivery model as the optimal choice for the last-mile delivery and complete allocation of the number of delivery workers
Water, society and urbanization in the 19th century Belgrade: Lessons for adaptation to the climate change
This paper traces urban history of Belgrade in the 19th century by looking into its waterscape in the context of its
transformation as the capital of the Princedom of Serbia. Aiming to underline the importance of water as a resource, with the
view to contemporary environmental concerns, we explore how citizens historically related to waterscape in everyday life and
created a specific socio-spatial water network through use of public baths on the river banks and public fountains, water
features and devices in the city. The paper outlines the process of establishing the first modern public water supply system on
the foundations of the cityās historical Roman, Austrian and Ottoman waterworks. It also looks at the TopÄider River as the
most telling example of degradation of a culturally and historically significant urban watercourse from its natural, pastoral and
civic past to its current polluted and hazardous state. Could the restitution of the TopÄider River be considered as a legacy of
sustainability for future generations, and are there lessons to be learned from the urban history which can point to methods of
contemporary water management
Znanje o verovanju: teorija sekularizacije u savremenim empirijskim istraživanjima u Evropi i Srbiji u 21. veku
Jedna od najuticajnijih teorija u sociologiji religije je svakako teorija sekularizacije. U radu prvo pokuÅ”avamo da okvirno definiÅ”emo ovaj viÅ”eznaÄan i kompleksan pojam ukazujuÄi na menjanje njegovog sadržaja kroz istoriju. OpÅ”te slaganje o pojmu i procesu sekularizacije viÅ”e zavisi od usvojene definicije religije u konretnim teorijskim pristupima tom fenomenu nego od oÄiglednih empirijskih pokazatelja. Pristalice smo shvatanja da je sekularizacija reverzibilan proces, i da ovu teoriju ne treba odbaciti, veÄ revidirati. Iako je Evropa mesto gde je teorija sekularizacije doživela svoju empirijsku verifikaciju, novija istraživanja pokazuju da ni ovaj prostor nije religijski homogen. U tumaÄenju revitalizacije religije u Srbiji sociolozi koriste dva teorijska okvira. Prvi se odnosi na povratak religije u javni prostor, Å”to nije upitno, dok se drugi bavi āterminalnom veromā i individualnim potrebama vernika za pobožnoÅ”Äu. Bez obzira da li se priklanjamo teoriji sekularizacije i/ili zastupamo concept desekularizacije i post(sekularnog) obrta, samo dobro osmiÅ”ljena empirijska socioloÅ”ka istraživanja (kvantitativna i kvalitativna) mogu pomoÄi u nauÄnom objaÅ”njavanju i razumevanju složene savremene religijske situacije
Genotype x Environment Interaction for Wheat Yield Traits Suitable for Selection in Different Seed Priming Conditions
Different seed priming treatments are widely used in order to improve the nutritional status of wheat, as well as to improve its grain yield and yield- related traits. The present study aimed to evaluate the impact of seed priming with zinc oxide nanoparticles (ZnO NPs) on the yield related traits, such as, field emergence, plant height, spike length and grain yield per plant of four winter wheat genotypes (Triticum aestivum L.) during two vegetation seasons of 2018/2019 and 2019/2020. The seeds of each wheat genotypes were primed with different concentrations of ZnO NPs (0 mg L-1, 10 mg L-1, 100 mg L-1 and 1000 mg L-1) for 48 h in a dark box by continuous aeration and were sown in soil pots with 60-70% moisture content until full maturity. The additive main effects and multiplicative interaction (AMMI) models were used to study the genotype environment effects. The results indicated that the plants response to ZnO nanoparticles significantly increased all of the observed traits of the wheat, while its maximum rates reduced the traits of the wheat. The AMMI analysis revealed the very complex nature of the variation observed in the trial and showed the significant effect of the GxE interaction, in which the first main component was significant for all components
The importance of potassium channels in the mechanism of the relaxing effect of pentoxifylline on isolated rat uteri
Background. Pentoxifylline is a methylxanthine derivative that is used to treat peripheral vascular disease. One of the mechanisms of action of pentoxifylline is the vasodilatation of blood vessels. This study examined the effect of increasing pentoxifylline concentrations on the contractility of isolated rat uteri in the presence of a potassium channel antagonist. Methods. The uteri were isolated from virgin Wistar rats (180-220 g) and suspended in an isolated organ bath chamber containing De Jalon's solution and aerated with 95% O2 and 5% CO2. The temperature was maintained at 37ŃC. Isometric contractions were recorded using an isometric force transducer (Ugo Basile). The preload of the preparation was approximately 1 g. The uteri were allowed to contract spontaneously or in the presence of Ca2+ (0.018 and 0.36 mM) and acetylcholine (ACh) and were treated with pentoxifylline. Results. Pentoxifylline caused concentration-dependent inhibition of spontaneous rhythmic uterine activity and uterine activity caused by calcium Ca2+ (0.018 mM and 0,36 mM). We showed that the inhibitory effects of pentoxifylline depend on the type of muscle contractions activated and that the inhibitory effect is significantly stronger for spontaneous rhythmic activity and forin Ca2 -induced contractions of isolated rat uteri+. The relaxing effect of pentoxifylline depends on the calcium concentration in the medium. Pentoxifylline exerted the weakest relaxant effects on contractions induced by acetylcholine. In contrast to methylene blue, tetraethylammonium, or 4-aminopyridine, glibenclamide did not antagonise the relaxing effect of pentoxifylline on isolated rat uteri. Conclusion. The results obtained suggest that the mechanism of action of pentoxifylline does not lead to the opening of KATP channels. However, the opening of BKCa and voltage-dependent Ca2+ channels had some role, but to varying degrees, in the mechanism of the relaxing effect of pentoxifylline on the spontaneous rhythmic activity and calcium-induced contractions of isolated rat uteri. Our results provide additional confirmation of the dominance of the NO/cGMP signaling pathway in the mechanism of the relaxing effect of pentoxifylline (because the presence of methylene blue significantly antagonised this effect) in relation to the opening of potassium channels, especially KATP channels. These results indicate that pentoxifylline could be a potential tocolytic drug.Cilj. Pentoksifilin, koji se koristi za leÄenje perifernih vaskularnih oboljenja, je derivat metilksantina. Jedan od naÄina delovanja pentoksifilina je prouzrokovanje vazodilatacije krvnih sudova. U ovom radu ispitivali smo efekat rastuÄih koncentracija pentoksifilina na kontraktilnost izolovanog uterusa pacova, u prisustvu blokatora kalijumskih kanala. Metode. Uterusi, koji su izolovani od neparenih ženki pacova Wistar soja (180-220 g), držani su u kupatilu za izolovane organe na temperaturi od 37oC, u De Jalon-ovom rastvoru kroz koji je propuÅ”tana smeÅ”a gasova od 95% kiseonika i 5% ugljendioksida. Izometrijske kontrakcije su registrovane koriÅ”Äenjem izometrijskog transdjusera Ugo Basile, pri optereÄenju preparata od 1 g. Ispitivan je efekat pentoksifilina na kontrakcije za vreme spontane ritmiÄke aktivnosti i u prisustvu kalcijuma, Ca2+ (0.018 and 0.36 mM)) i acetilholina (ACh). Rezultati. Pentoksifilin je prouzrokovao koncentracijski zavisnu inhibiciju spontane ritmiÄke aktivnosti, kao i fazne aktivnosti prouzrokovane kalcijumom. Inhibicijski efekt pentoksifilina zavisio je od tipa aktivacije glatkog miÅ”iÄa uterusa. On je ispoljio znaÄajno jaÄi relaksirajuÄi efekt na spontanu ritmiÄku aktivnost i kontrakcije prouzrokovane sa 0.018 mM kalcijuma. Njegov relaksirajuÄi efekt zavisi i od koncentracije Ca2+ u medijumu..Najslabiji relaksirajuÄi efekat pentoksifilina je zabeležen na acetilholinskom tipu aktivacije. Nasuprot metilenskom plavilu, 4-aminopiridinu i tetraetilamonijumu, glibenklamid ne antagonizuje relaksirajuÄi efekat pentoksifilina na izolovanom uterusu pacova. ZakljuÄak. Dobijeni rezultati sugeriÅ”u da u mehanizmu relaksantnog delovanja pentoksifilina nije zastupljeno otvaranje ATP kalijumskih kanala. MeÄutim, otvaranje BKCa i voltažno zavisnih Ca2+ kalijumskih kanala ima izvestan znaÄaj, ali u razliÄitom stepenu, u mehanizmu relaksirajuÄeg delovanja pentoksifilina na spontanu ritmiÄku aktivnost i kontrakcije prouzrokovane kalcijumom. NaÅ”i rezultati su dodana potvrda o dominaciji NO/cGMP signalinih puteva kojima pentoksifilin prouzrokuje relaksaciju glatkih miÅ”iÄnih Äelija uterusa (jer metilensko plavilo znaÄajno antagonizuje njegov efekt), u odnosu na otvaranje kalijumskih kanala, posebno ATP zavisnih kalijumskih kanala. Rezultati ukazuju da bi pentoksifilin mogao da bude potencijalni tokolitiÄki lek.nul
Multi-axis integrated Hall magnetic sensors
Conventional Hall magnetic sensors respond only to the magnetic field component perpendicular to the surface of the sensor die. Multi-axis sensing capability can be provided in the following two ways: (a) by integrating magnetic flux concentrators on the die, and (b) by using vertical Hall devices. Here we review the most important two-and three-axis integrated Hall magnetic sensors based on these concepts. Their applications include mapping of magnetic fields and sensing angular position
Within-field correlation between satellite-derived vegetation indices and grain yield of wheat
This research aimed to inspect the correlation coefficients, during the crop growth stages, between vegetation indices (VIs) derived from Sentinel-2 imagery and grain winter wheat yield derived from yield monitoring and select the most promising indices for monitoring crop growth and yield estimation. METHOD / DESIGN: The satellite images in 10m resolution were selected based on crop growth stages, from the end of tillering phase (beginning of March 2019) until the full ripening (end of June 2019). For the analysis, the BBCH-scale for cereals was used. Yield observations were performed at harvest on five fields in one season and twelve VIs were calculated across 10 growth stages. To designate their correlation and dependence, a statistical comparison of the VIs and yield was made. The Pearsonās and Spearmanās correlation coefficients were calculated, and their statistical significance was tested using p-value (at p=0.01, p=0.05). RESULTS: According to the crop growth stages, the highest correlation coefficients were detected from the early boot stage (BBCH 41) until the middle of development of the fruiting stage (BBCH 73 ā early milk). In that period the correlation coefficients varied from 0.39 to 0.84 depending on the field. Based on the location, the highest correlation coefficient values for all 12 indices were recorded for the parcel named C-6 (April 15), and the lowest values for the parcel named C-10 (June 29). Most of the indices showed statistically significant dependence (at the p<0.01 and p<0.05 significant levels) on the yield in the first five growth stages except the chlorophyll vegetation index (CVI) for the parcel named C-11 (p=0.21, p=0.39). CONCLUSIONS: To conclude, the last growth stage named ripening showed the lowest values both for correlation coefficient and statistical significance which means that VIs also had low values because the reflectance is weak in this growth stage and wheat is about to be harvested. In the first five stages, VIs showed significantly high spectral reflectance values since in this period the leaf is full of chlorophyll pigments. Analyzing the correlation coefficient in different stages of wheat growth, we look at the current state of crops and have the opportunity to take appropriate measures in time to increase yields or save inputs at specific locations
Effect of inoculation with PGPR on basil antioxidant activity
Basil (Ocimum basilicum L.) is a widely utilized culinary herb. It is used to flavour foods such as vegetables, meats, fish, etc. In traditional medicine is used for treatment of various disorders such as colds, respiratory diseases, cardiovascular diseases, metabolic and gastrointestinal disorders, etc. The effects of climate changes on agriculture can result in lower yield and nutritional quality of plants. The inoculation of plants with plant growth-promoting rhizobacteria (PGPR) such as Azotobacter, Streptomyces, and Bacillus are well known to lead to improvement in germination, growth, and yield. Also, it was found that PGPR enhance defence capacity of the plant. In this study, the basil seed were inoculated with selected PGPR isolates: Bac3, Azb, and Act. Control seeds were immersed into distilled water. After 6 weeks plant material was collected, and methanol extracts were prepared for antioxidant determinations. The changes in total phenol and flavonoid content, as well as antioxidant activity, were monitored. PGPR applied in the experiment have not cause significant changes in total phenol content. However, treatments with Azb and Act isolates have increased flavonoid content in basil plants. The antioxidant activity of basil plant has been measured as the ability of plant extracts to reduce DPPH radicals. Obtained results show that only treatment with Azb isolates significantly increases the antioxidant activity of basil plants. Results obtained in this study suggested that investigated isolates have different effects on the antioxidant characteristics of the basil plant. Further investigation is still needed to explore the possibility of using these PGPRs as potent bio-fertilizer in basil production
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