The Conjugated-Circuit Model Revisited

Two formulae for computing resonance energies of benzenoid hydrocarbons within the conjugated-circuit model are considered. The first is Randić\u27s original formula developed in 1976 and the second is the result of the analysis of the foundations of the conjugated-circuit model in term s of the Simpson-Herndon model Hamiltonians. Both formulae produce very similar resonance energies. This analysis thus justifies Randić\u27s ini ti al choi ce of circuits and their parameters

Clar Structures in Fractal Benzenoids

The aromaticity of fractal benzenoids was studied by the VB approach of Herndon and Hosoya based on the Clar structures. The results are compared with the logarithmic model and the conjugated-circuit model. It appears that the simplest model, i.e. the logarithmic model, is the most convenient one for use in this class of benzenoids

GTI-space : the space of generalized topological indices

A new extension of the generalized topological indices (GTI) approach is carried out torepresent 'simple' and 'composite' topological indices (TIs) in an unified way. Thisapproach defines a GTI-space from which both simple and composite TIs represent particular subspaces. Accordingly, simple TIs such as Wiener, Balaban, Zagreb, Harary and Randićconnectivity indices are expressed by means of the same GTI representation introduced for composite TIs such as hyper-Wiener, molecular topological index (MTI), Gutman index andreverse MTI. Using GTI-space approach we easily identify mathematical relations between some composite and simple indices, such as the relationship between hyper-Wiener and Wiener index and the relation between MTI and first Zagreb index. The relation of the GTI space with the sub-structural cluster expansion of property/activity is also analysed and some routes for the applications of this approach to QSPR/QSAR are also given

Influence od storage duration on primary root and germ lenght of sunflower hybrid seed

Dorađeno sjeme (nezaprašeno) hibrida suncokreta Fakir, Orion i Apolon skladišteno je 36 mjeseci u dvoslojnim papir vrećama, u podnom betonskom skladištu s termoizolacijom (relativna vlaga zraka 55-60% i temperatura 10-12°C). Analiza istraživanih svojstava (dužina primarnog korijena i klice) bila je na početku skladištenja i nakon svakih 12 mjeseci skladištenja tijekom tri godine istraživanja. Rezultati istraživanja su pokazali da sjeme hibrida Fakir ima duži primarni korijen i klicu (0.3-0.6 cm i 0.3-0.7 cm) od Oriona i Apolona na početku i na kraju skladištenja. Hibrid Apolon ima najkraći primarni korijen i klicu (5.4 cm i 2.2 cm) na početku, kao i na kraju skladištenja (4.3 cm i 1.6 cm). Kod svih hibrida najveće smanjenje dužine primarnog korijena i klice bilo je poslije 36 mjeseca skladištenja. Dobivene razlike su statistički vrlo značajne za sva istraživana svojstva (hibrid, dužina skladištenja, interakcija hibrid x dužina skladištenja).After seed processing, sunflower seed Fakir, Orion and Apolon has been storage for 36 months. Seed samples were packed in two film paper bag and storage in two different storage. Concrete floor and storage with termoizolation (relative air humidity 55-60 % and air temperature 10 °C – 12 °C). In the time of storage, every 12 months, seed samples was getting and seed properties has been analyzed. After 36 months, primary root and germ length were measured. Results of this investigations approved, that Fakir hybrid seed has higher on primary root and germ length in accordance with Orion and Apolon. It was conclude that decreasing of primary root and germ length depend on hybrid and storage duration. Apolon hybrid had the largest decreasing of primary root (1.1cm) and germ length (0.6cm). Fakir hybrid had the smallest decreasing. Each hybrids in this investigations had the largest decreasing of primary root and germ length after 24 months of storage. Hybrid and storage duration, statistically very significant influence on seed quality decreasing

Influence od storage duration on primary root and germ lenght of sunflower hybrid seed

Dorađeno sjeme (nezaprašeno) hibrida suncokreta Fakir, Orion i Apolon skladišteno je 36 mjeseci u dvoslojnim papir vrećama, u podnom betonskom skladištu s termoizolacijom (relativna vlaga zraka 55-60% i temperatura 10-12°C). Analiza istraživanih svojstava (dužina primarnog korijena i klice) bila je na početku skladištenja i nakon svakih 12 mjeseci skladištenja tijekom tri godine istraživanja. Rezultati istraživanja su pokazali da sjeme hibrida Fakir ima duži primarni korijen i klicu (0.3-0.6 cm i 0.3-0.7 cm) od Oriona i Apolona na početku i na kraju skladištenja. Hibrid Apolon ima najkraći primarni korijen i klicu (5.4 cm i 2.2 cm) na početku, kao i na kraju skladištenja (4.3 cm i 1.6 cm). Kod svih hibrida najveće smanjenje dužine primarnog korijena i klice bilo je poslije 36 mjeseca skladištenja. Dobivene razlike su statistički vrlo značajne za sva istraživana svojstva (hibrid, dužina skladištenja, interakcija hibrid x dužina skladištenja).After seed processing, sunflower seed Fakir, Orion and Apolon has been storage for 36 months. Seed samples were packed in two film paper bag and storage in two different storage. Concrete floor and storage with termoizolation (relative air humidity 55-60 % and air temperature 10 °C – 12 °C). In the time of storage, every 12 months, seed samples was getting and seed properties has been analyzed. After 36 months, primary root and germ length were measured. Results of this investigations approved, that Fakir hybrid seed has higher on primary root and germ length in accordance with Orion and Apolon. It was conclude that decreasing of primary root and germ length depend on hybrid and storage duration. Apolon hybrid had the largest decreasing of primary root (1.1cm) and germ length (0.6cm). Fakir hybrid had the smallest decreasing. Each hybrids in this investigations had the largest decreasing of primary root and germ length after 24 months of storage. Hybrid and storage duration, statistically very significant influence on seed quality decreasing

An Evaluation of Image Velocimetry Techniques under Low Flow Conditions and High Seeding Densities Using Unmanned Aerial Systems

Image velocimetry has proven to be a promising technique for monitoring river flows using remotely operated platforms such as Unmanned Aerial Systems (UAS). However, the application of various image velocimetry algorithms has not been extensively assessed. Therefore, a sensitivity analysis has been conducted on five different image velocimetry algorithms including Large Scale Particle Image Velocimetry (LSPIV), Large-Scale Particle Tracking Velocimetry (LSPTV), Kanade−Lucas Tomasi Image Velocimetry (KLT-IV or KLT), Optical Tracking Velocimetry (OTV) and Surface Structure Image Velocimetry (SSIV), during low river flow conditions (average surface velocities of 0.12−0.14 m s - 1 , Q60) on the River Kolubara, Central Serbia. A DJI Phantom 4 Pro UAS was used to collect two 30-second videos of the surface flow. Artificial seeding material was distributed homogeneously across the rivers surface, to enhance the conditions for image velocimetry techniques. The sensitivity analysis was performed on comparable parameters between the different algorithms, including the particle identification area parameters (such as Interrogation Area (LSPIV, LSPTV and SSIV), Block Size (KLT-IV) and Trajectory Length (OTV)) and the feature extraction rate. Results highlighted that KLT and SSIV were sensitive to changing the feature extraction rate; however, changing the particle identification area did not affect the surface velocity results significantly. OTV and LSPTV, on the other hand, highlighted that changing the particle identification area presented higher variability in the results, while changing the feature extraction rate did not affect the surface velocity outputs. LSPIV proved to be sensitive to changing both the feature extraction rate and the particle identification area. This analysis has led to the conclusions that for surface velocities of approximately 0.12 m s - 1 image velocimetry techniques can provide results comparable to traditional techniques such as ADCPs. However, LSPIV, LSPTV and OTV require additional effort for calibration and selecting the appropriate parameters when compared to KLT-IV and SSIV. Despite the varying levels of sensitivity of each algorithm to changing parameters, all configuration image velocimetry algorithms provided results that were within 0.05 m s - 1 of the ADCP measurements, on average

Amoeba Techniques for Shape and Texture Analysis

Morphological amoebas are image-adaptive structuring elements for morphological and other local image filters introduced by Lerallut et al. Their construction is based on combining spatial distance with contrast information into an image-dependent metric. Amoeba filters show interesting parallels to image filtering methods based on partial differential equations (PDEs), which can be confirmed by asymptotic equivalence results. In computing amoebas, graph structures are generated that hold information about local image texture. This paper reviews and summarises the work of the author and his coauthors on morphological amoebas, particularly their relations to PDE filters and texture analysis. It presents some extensions and points out directions for future investigation on the subject.Comment: 38 pages, 19 figures v2: minor corrections and rephrasing, Section 5 (pre-smoothing) extende