Graphs for which the least eigenvalue is minimal, II

We continue our investigation of graphs G for which the least eigenvalue ?(G) is minimal among the connected graphs of prescribed order and size. We provide structural details of the bipartite graphs that arise, and study the behaviour of ?(G) as the size increases while the order remains constant. The non-bipartite graphs that arise were investigated in a previous paper [F.K. Bell, D. Cvetkovic', P. Rowlinson, S.K. Simic', Graphs for which the least eigenvalue is minimal, I, Linear Algebra Appl. (2008), doi: 10.1016/j.laa.2008.02.032]; here we distinguish the cases of bipartite and non-bipartite graphs in terms of size. Erratum is published in: Richard A Brualdi, 'From the Editor-in-Chief', Linear Algebra Applications, 432(1) pp.1-6, 01/2010 &nbsp

DETECTION OF TEXTURE-LESS OBJECTS BY LINE-BASED APPROACH

This paper proposes a method for tackling the problem of scalable object instance detection in the presence of clutter and occlusions. It gathers together advantages in respect of the state-of-the-art object detection approaches, being at the same time able to scale favorably with the number of models, computationally efficient and suited to texture-less objects as well. The proposed method has the following advantages: a) generality – it works for both texture-less and textured objects, b) scalability – it scales sub-linearly with the number of objects stored in the object database, and c) computational efficiency – it runs in near real-time. In contrast to the traditional affine-invariant detectors/descriptors which are local and not discriminative for texture-less objects, our method is based on line segments around which it computes semi-global descriptor by encoding gradient information in scale and rotation invariant manner. It relies on both texture and shape information and is, therefore, suited for both textured and texture-less objects. The descriptor is integrated into efficient object detection procedure which exploits the fact that the line segment determines scale, orientation and position of an object, by its two endpoints. This is used to construct several effective techniques for object hypotheses generation, scoring and multiple object reasoning; which are integrated in the proposed object detection procedure. Thanks to its ability to detect objects even if only one correct line match is found, our method allows detection of the objects under heavy clutter and occlusions. Extensive evaluation on several public benchmark datasets for texture-less and textured object detection, demonstrates its scalability and high effectiveness

Comparative analyse of foodstuff geographical indications in the Western Balkans

The aim of this paper is to determine the current situation in the field of geographical indications schemes (GI), obstacles for futures development and to provide recommendations for GIs development in Serbia, Bosnia and Herzegovina and Montenegro. GIs quality schemes provide confirmation to consumers that foodstuff is a traditional product produced in a certain area and with certain attributes. Although the Western Balkan countries are reach in well-known traditional products and have excellent ago-ecological conditions for GIs production, this quality schemes are not developed. In this paper are applied comparative methodology, literature review and field research. Results are showing that path to improvement GIs is in the further legal framework harmonization with EU legal framework, providing flexibility for registration of the GIs foodstuff processing capacities, support to the producer's organization, shifting of the national GIs recognition to the EU, systematic support to the GIs etc

Consideration of Energy Flows in the Life Cycle of Energy Production from Biogas

The aim of this paper is to present the energy flows in the life cycle of the biogas cogeneration system, as well as their mutual relations, starting from providing of feedstock materials(corn silage and cow manure), anaerobic digestion, cogeneration up to the digestate as fertilizer on agricultural land. The cogeneration process has been considered according to the performance of the biogas plant located on the Mirotin dairy farm in Vrbas (Serbia). For evaluation of energy flows in this work were used four energy indicators. According to the Life Cycle Energy Assessment approach, results obtained in this study have shown that the biogas cogeneration process has positive energy balances and this process is energy sustainable. The applied approach in this research can be adjusted to any biogas power plant since it complies with the main material and energy balances.Cilj ovog rada je da prikaže tokove energije u životnom ciklusu biogas kogeneracionog sistema, kao i njihove međusobne odnose, počev od obezbeđivanja sirovine (kukuruzna silaža i kravlji stajnjak), anaerobne digestije, kogeneracije, pa do digestata. kao đubrivo na poljoprivrednom zemljištu. Proces kogeneracije je razmatran prema performansama biogas postrojenja koje se nalazi na farmi mleka Mirotin u Vrbasu (Srbija). Za evaluaciju energetskih tokova u ovom radu korišćena su četiri energetska indikatora. Prema LCEA pristupu, rezultati dobijeni u ovoj studiji su pokazali da proces kogeneracije biogasa ima pozitivan energetski bilans i da je ovaj proces energetski održiv. Primenjeni pristup u ovom istraživanju može se prilagoditi bilo kojoj elektrani na biogas jer je u skladu sa osnovnim materijalnim i energetskim bilansima

Assessment of Emissions into the Atmosphere from Biogas Cogeneration Plant in Serbia

Biogas je gasna smeša koja nastaje tretmanom otpadnih tokova u procesu anaerobne digestije. Proizvodnja električne energije iz kogeneracionih postrojenja koja koriste biogas je u porastu u Republici Srbiji. U ovom radu je izvršena kvantifikacija emisija (ugljen-dioksida, sumpor-dioksida, oksida azota, metana i čestica) u atmosferu iz tipičnog biogasnog postrojenja u Republici Srbiji, instalisanog kapaciteta od 1 MW. Dobijeni rezultati su pokazali da proizvodnja električne energije iz kogeneracije biogasa predstavlja dobro rešenje u cilju smanjenja emisije gasova sa efektom staklene bašte i racionalne upotrebe prirodnih resursa

Energetska valorizacija otpadnih voda iz industrije prerade mleka u Srbiji

Otpadne vode industrije prerade mleka predstavljaju veliko optrećenje po životnu sredinu. U ovom radu istraživan je potecijal za energetsku valorizaciju anaerobnog tretmana otpadnih voda iz indsitrije prerade mleka u Republici Srbiji. Dobijeni rezultati su pokazali da se otpadne vode iz indus-trije prerade mleka mogu uspešno koristiti kao resurs za proizvodnju toplotne i električne energije, kao i u supstituciji prirodnog gasa u Republici Srbiji

New insights into sesquiterpene lactones composition of Western Balkan’s genus Amphoricarpos revealed by rapid resolution liquid chromatography coupled with quadrupole time-of-flight mass spectrometry

This study revealed results from reinvestigation of sesquiterpene lactones composition in the crude and leaf surface extracts of Amphoricarpos plants by rapid resolution liquid chromatography (RRLC) coupled with quadrupole time-of-flight mass spectrometry (QToF MS) and the tentative identification of undescribed sesquiterpene lactones is presented.11th Conference on Medicinal and Aromatic Plants of Southeast European Countries, (11th CMAPSEEC), Ohrid, North Macedonia, 6–10 October 202

Popliteal artery injury following traumatic knee joint dislocation in a 14-year-old boy: A case report and review of the literature

Introduction. Posterior knee joint dislocation associated with injury of the popliteal artery in children is an extremely rare condition. Rapid diagnosis and treatment are essential for limb salvage and function. Case report. We reported a 14-year-old boy who suffered traumatic displacement of the right knee and contusion of the popliteal artery during motorcycle accident. The diagnosis was confirmed using Doppler and duplex ultrasonography and digital substraction transfemoral arteriography. The urgent surgical procedure was performed using posterior approach to the popliteal artery. During the surgical exploration, rupture of the posterior cruciate ligament associated with thrombosed popliteal artery have been found. The damaged popliteal artery was resected and replaced with autologous saphenous vein graft. The last stage of the procedure was a transosseous femoral fixation of posterior circuate ligament. A 3-year-follow-up after the surgery demonstrated intact arterial perfusion and very good function of the knee with a minimal difference as compared with the contralateral knee. Conclusion. Combined orthopedic and vascular injuries are very rare in children. They require combined treatment. [Projekat Ministarstva nauke Republike Srbije, br. 175008

Biogas tehnologija u funkciji proizvodnje energije

Potreba za smanjenjem upotrebe fosilnih goriva, zbog štetnog uticaja na životnu sredinu i sve veća potražnja za energijom, doveli su do proizvodnje energije iz obnovljivih izvora. Pristup čistoj i obnovljivoj energiji postao je imperativ za društveni napredak. Poboljšanje postojećih resursa biomase u efikasne nosioce energije kao što je biogas iz anaerobne digestije ima potencijal da obezbedi čistu i pouzdanu energiju, uz zaštitu životne sredine, racionalno korišćenje prirodnih resursa i stvaranje novih radnih mesta. Uz smanjenje emisije gasova staklene bašte, biogas poboljšava energetsku sigurnost i, kao obnovljivi izvor energije, omogućava eksploataciju otpadnih tokova. Biogas proizveden u sistemu anaerobne digestije se obično sagoreva u kogeneracionoj jedinici da bi se proizvela toplota, električna energija i energija za hlađenje. Konačno, biogas se može prečistiti u biometan, koristiti kao gorivo u vozilima ili ubrizgati u nacionalne mreže prirodnog gasa. Digestat kao nusproizvod anaerobne digestije je pouzdan materijal za upotrebu kao đubrivo u poljoprivredi. U ovom radu sumirano je korišćenje biogasa za proizvodnju toplotne, električne energije, rashladne energije, kao i goriva sa pregledom postojećih tehnologija za njegovu upotrebu. Takođe, ovaj rad pruža priliku da se razmotri uloga biogasa u budućim energetskim sistemima.The need to reduce the use of fossil fuels, due to the harmful impact on the environment and the growing energy demand, have led to the production of energy from renewable sources. Access to clean and renewable energy has become imperative for social progress. Improving existing biomass resources into efficient energy carriers such as biogas from anaerobic digestion has the potential to provide clean and reliable energy, with environmental protection, rationally using natural resources and generation of new jobs. Along with reducing greenhouse gas emissions, biogas improves energy security and, as a renewable energy source, enables the exploitation of waste streams. Biogas produced in an anaerobic digestion system is usually burned in a cogeneration unit to produce heat, electricity, and cooling energy. Finally, biogas can be purified into biomethane, used as a fuel for vehicles, or injected into national natural gas networks. Digestate as a by-product of anaerobic digestion is a reliable material for use as a fertilizer in agriculture. This paper summarizes the use of biogas for the production of heat, electricity, cooling energy, as well as fuel with an overview of existing technologies for its use. Also, this paper provides an opportunity to consider the role of biogas in future energy systems

Supplementary material for the article: Cvetković, M.; Damjanović, A.; Stanojković, T. P.; Đorđević, I.; Tešević, V.; Milosavljević, S.; Gođevac, D. Integration of Dry-Column Flash Chromatography with NMR and FTIR Metabolomics to Reveal Cytotoxic Metabolites from Amphoricarpos Autariatus. Talanta 2020, 206. https://doi.org/10.1016/j.talanta.2019.120248

Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/3348]Supplementary material for: [https://www.sciencedirect.com/science/article/pii/S0039914019308811?via%3Dihub