Algorithms for task assignment in wireless networks of microcontroller sensor nodes and autonomous robots

U bežičnoj mreži senzora i robota, senzorski moduli vrše nadzor fizičkih veličina od značaja, a roboti imaju ulogu izvršilaca zadataka koji im se dodeljuju primenom odgovarajućeg algoritma. Nakon detekcije događaja od strane statičkih senzorskih čvorova i prosleđivanja informacija o događajima robotima, potrebno je dodeliti zadatke robotima na efikasan način. Dodela zadataka vrši se u skladu sa prirodom različitih scenarija koji se mogu javiti u praksi. U okviru disertacije razmatran je slučaj kada se konkurentno javlja više događaja kojima je potrebno dodeliti izvršioce. U pogledu energetske efikasnosti, u ovakvim sistemima kao ključni problemi javljaju se minimizacija ukupne dužine kretanja robota i optimizacija komunikacije u mreži. Od komunikacinih protokola za otkrivanje izvršilaca, u ovoj disertaciji predstavljena su poboljšanja postojećeg iMesh protokola i uveden je novi vCell protokol zasnovan na lokalizovanom formiranju ćelija Voronoi dijagrama. Takođe, upoređene su performanse novog protokola sa postojećim (pravougaoni kvorum i iMesh) u gustim mrežama, retkim mrežama i mrežama sa rupama u topologiji. Uz to, uvedeni su algoritmi za ažuriranje lokacije kojima mreža reaguje na kretanje robota. Rezultati simulacija pokazuju da vCell postiže efikasnost blizu 100% u nalaženju najbližeg robota u gustim mrežama. U retkim mrežama, efikasnost mu je do 40% bolja u odnosu na ostala rešenja. Kao glavni rezultat u disertaciji prikazani su novi algoritmi za dodelu robota kao izvršilaca zadataka događajima, čime su prevaziđni nedostaci više do sada poznatih rešenja ovog problema. Za zadati skup događaja i skup robota, svakom događaju dodeljen je po jedan robot koji je zadužen za obilazak lokacije događaja. Tokom pojedinačnih rundi, robotima je dozvoljen obilazak jednog događaja kada se vrši uparivanje, ili više događaja, kada se vrši sekvencijalna dodela. U distribuiranom slučaju, statički senzorski uređaji detektuju događaje i prijavljuju ih obližnjim robotima. Algoritam PDM koji se odnosi na unapređeno uparivanje sa mogućnošću razmene partnera, eliminiše dugačke ivice koje se mogu javiti prilikom uparivanja. Algoritam SQD za sekvencijalnu dodelu događaja robotima iterativno pronalazi par robot-događaj sa najmanjim međusobnim rastojanjem, uvrštava izabrani događaj u listu za oblazak izabranog robota i ažurira poziciju robota. Takođe su predložene generalizacije koje omogućavaju da događaji budu posećeni od strane više robota i koje uzimaju u obzir vremenska ograničenja. Distribuirani algoritam MAD, koji je zasnovan na iMesh informacionoj strukturi i lokalnim aukcijama u robotskoj mreži, vrši dodelu robota događajima na lokalizovan i energetski efikasan način. Rezultati simulacija potvrđuju prednosti predloženih algoritama u odnosu na postojeća rešenja, kako u pogledu skraćivanja dužina putanja robota, tako i u produženju životnog vremena sistema.In a typical wireless sensor and robot network, sensor nodes monitor physical values of interest, while robots perform some automated tasks. The tasks are assigned to robots by means of an appropriate algorithm. Upon the occurrence of events which are detected by sensor nodes, the information about the events needs to be delivered to robots. Afterwards, it is necessary to assign tasks to robots in an efficient way. Task assignment is performed according to the nature of different scenarios which might occur in practice. This thesis is focused on the case when multiple events, all of which require to be visited by robots, happen simultaneously. Regarding energy efficiency, the key issues which arise in such systems are minimization of robot travel paths, and optimization of the network traffic. In this thesis, the following service discovery protocols are presented: improvements of the existing iMesh protocol, and the novel vCell protocol, which is based on localized formation of an information structure which resembles Voronoi diagram. Furthermore, the performaces of new vCell protocol is compared with the existing protocols (Quorum and iMesh) in dense networks, sparse networks, and networks with holes in topology. Also, location update algorithms are introduced, which deal with robot mobility. The simulations show that vCell achieves nearly 100% success rate in finding the nearest robot in dense networks. In sparse networks, it outperforms the other existing solutions by up to 40%. As a key contributtion, the novel dispatch lgorithms have been introduced. Given a set of events and a set of robots, the dispatch problem is to allocate one robot for each event to visit it. In a single round, each robot may be allowed to visit only one event (matching dispatch), or several events in a sequence (sequence dispatch). In a distributed setting, each event is discovered by a sensor and reported to a robot. In this thesis, novel algorithms are presented, whichh are aimed at overcoming the shortcomings of several existing solutions. Pairwise distance based matching algorithm (PDM) eliminates long edges by pairwise exchanges between matching pairs. Sequence dispatch algorithm (SQD) iteratively finds the closest event-robot pair, includes the event in dispatch schedule of the selected robot and updates its position accordingly. When event-robot distances are multiplied by robot resistance (inverse of the remaining energy), the corresponding energybalanced variants are obtained. Also, generalizations are introduced which handle multiple visits and timing constraints. Distributed algorithm MAD is based on information mesh infrastructure and local auctions within the robot network for obtaining the optimal dispatch schedule for each robot. The simulations conducted confirm the advantages of our algorithms over other existing solutions in terms of average robot-event distance and lifetime

The influence of polleniser on biological properties and quality of apple (Malus domestica Borkh.) fruits

Istraživanjima u okviru ove doktorske disertacije ispitan je uticaj oprašivača na biološke osobine novointrodukovanih sorti jabuke: ‘Gala Must’, ‘Red Elstar’, ‘Rajka’ i ‘Topaz’ u agroekološkim uslovima Čačka. Proučavane su fiziološke osobine (fenofaza cvetanja, fenofaza oprašivanja i oplođenja, i fenofaza zrenja plodova), pomološke osobine (morfometrijske, hemijske i organoleptičke) i produktivne osobine (prinos po stablu i prinos po jedinici površine) navedenih sorti jabuke u kombinacijama međusobnih oprašivanja, kao i u varijanti slobodnog oprašivanja. Fenofaza cvetanja i zrenja ploda je utvrđena standardnim metodama za ovu vrstu istraživanja. Ispitana je klijavost polena in vitro proučavanih sorti jabuke, kvantitativna efikasnost rasta polenovih cevčica (broj polenovih cevčica i njihov rast u pojedinim delovima stubića) metodom fluorescentne mikropskopije, kao i inicijalno i finalno zametanje plodova u zavisnosti od oprašivača. Morfometrijski parametri ploda (masa, visina, širina, indeks oblika, dužina peteljke i broj semenki u plodu), kao i hemijske osobine ploda (sadržaj ukupnih i rastvorljivih suvih materija, sadržaj ukupnih, invertnih šećera i saharoze, sadržaj ukupnih kiselina, pH vrednost soka ploda i sadržaj ukupnih mineralnih materija) utvrđeni su standardnim laboratorijskim metodama. Organoleptička ocena ploda (intenzitet dopunske boje pokožice, atraktivnost, ukus, aroma i konzistencija ploda) utvrđena je poentiranjem u skladu sa UPOV metodologijom navedenom u uputstvima za priznavanje i zaštitu sorti jabuke. Prinos ispitivanih sorti jabuke u zavisnosti od oprašivača utvrđen je računskim putem. Sorta ‘Rajka’ pripada grupi srednjeranocvetnih, dok ostale sorte pripadaju grupi srednjepoznocvetnih sorti jabuke. Po vremenu zrenja sorte ‘Gala Must’ i ‘Red Elstar’ su jesenje, dok su sorte ‘Rajka’ i ‘Topaz’ zimske sorte jabuke. Kvantitativni parametri rasta polenovih cevčica u stubiću tučka ispitivanih sorti jabuke ukazuju na postojanje uticaja genotipa oprašivača, ali i njegovog zahteva u pogledu temperaturnih uslova. Kod svih kompatibilnih kombinacija ukrštanja šest dana nakon oprašivanja konstatovan je prodor polenovih cevčica u bazu stubića, izuzev kod varijante slobodnog oprašivanja sorte ‘Gala Must’, kao i u kombinaciji ‘Rajka’ ‘Gala Must’ u drugoj godini ispitivanja. Kod svih kombinacija oprašivanja utvrđen je visok procenat inicijalnog i finalnog zametanja plodova, uslovljen sortom oprašivačem i godinom ispitivanja...The influence of pollenisers on biological properties of the newly introduced apple cultivars ‘Gala Must’, ‘Red Elstar’, ‘Rajka’ and ‘Topaz’ grown in the region of Čačak were investigated within the scope of this doctoral dissertation. Among the crosspollination, as well as in an open pollination variants within the cultivars abovementioned, the following parameters were studied: physiological properties (flowering phenophase, pollination and fertilisation phenophase, and fruit ripening phenophase), pomological properties (morphometric, chemical and organoleptic) and production properties (yield per tree and yield per unit land area). Flowering and fruit ripening phenophases were determined by using standard method. In vitro pollen germination rate of the studied apple cultivars, as well as quantitative efficacy of pollen tubes growth (number of pollen tubes and characteristics of their growth in particular regions of the style) monitored by fluorescent microscopy and the initial and final fruit set depending on polleniser, were analysed. Morphometric parameters of the fruit (weight, length, width, shape index, stalk length and seed number) along with chemical properties of the fruit (total and soluble solids content, total, inverted sugars and sucrose content, total acids, fruit juice pH value and total minerals content) were determined by standard methods. Organoleptic assessment of the fruit (over colour intensity, attractiveness, flavour, aroma and fruit consistency) involved grading based on UPOV instructions stated in cultivar release and apple cultivars protection procedures. Yield of the studied apple cultivars as influenced by polleniser was calculated manually. ‘Rajka’ belongs to the group of mid-early flowering cultivars, whereas the other assessed cultivars are classified as mid-late flowering. As regards harvest maturity, ‘Gala Must’ and ‘Red Elstar’ belong to the group of autumn cultivars, while ‘Rajka’ and ‘Topaz’ are winter cultivars. Quantitative parameters of pollen tubes growth in the style suggest not only the influence of polleniser genotype, but also point to temperature dependence of this influence. Six days after pollination pollen tubes were observed to penetrate the style base in all compatible pollination variants, except the cross ‘Rajka’ ‘Gala Must’ and open pollinated ‘Gala Must’ in the second year of the study. High initial and final fruit set were recorded in all pollination variants, and depended on polleniser and year of study..

Wood nematode species spectrum in the Mediterranean pine forests of Croatia

Background and purpose: This work presents the first research on wood nematodes in Croatia and it was done in order to address the question of the impact of dendropathogenic nematodes in pine stands in the coastal region of Croatia. To reveal this impact, the first step is the isolation and proper identification of the species spectrum of the existing wood nematodes. The aim of this study was to identify wood nematode species isolated from different pine tree species (Pinus halepensis, P. nigra, P. maritima) throughout the coastal region of Croatia and to identify their status as either pathogens or saprofits, which should build the basis for further research and understanding of the negative influence of this organisms on the decline of Mediterranian pine stands. Materials and methods: The research was carried out in 2013 and 2014 and it was done along the entire coastal region of Croatia. The experiments were carried out at two levels: by sampling wood nematodes and by monitoring pine longhorn beetles. Wood samples of dry or partly dry trees of P. nigra, P. halepensis and P. pinaster were collected throughout the year in the form of rings, branches, sawdust or wood chips without bark on different heights on the trees. Two techniques were used for the extraction of nematodes: Baermann funnel technique and Cobb`s method. In samples with an increased number of nematodes, some nematodes were separated and preserved in DESS solution for further morphological and molecular analysis. In the spring of 2014, the monitoring of pine longhorn beetle Monochamus galloprovincialis was done at 6 locations along the coastal region of Croatia were traps with pheromones were installed. The traps were placed in the treetops at a height of about 7 m in P. halepensis stands. The collected pine longhorn beetles were inspected for nematodes in the laboratory. Results: Saprophytic nematodes from the families Rhabditidae, Diplogasteridae and Cephalobidae dominated in the samples. In 9 wood samples pathogenic nematodes which belong to the genus Bursaphelenchus: B. mucronatus, B. sexdentati and B. minutes were detected . The pine wood nematode B. xylophilus was not found in the collected samples. A total of 109 pine longhorn beetles have been caught in traps with pheromones and their analysis showed that neither B. xylophilus nor native wood nematodes were present on them.. Conclusions: This is the first record of wood nematodes in the coastal region of Croatia. The results of this research confirm the presence of nematodes and their possible influence on the process of pine decline of the Mediterranean pine species in Croatia. The presence of M. galloprovincialis, the vector of highly damaging B. Xylophilus, has been confirmed during this research

Application of molecular markers in apple breeding

Apple is economically the most important species of genus Malus Miller. In respect of production, trade and consumption, it ranks first among deciduous fruit and third on a global scale among all fruit species. Apple breeding is carried out on a large scale in several scientific institutes throughout the world. Due to this activity, apple is a fruit species with the highest number of described monogenic traits; 76 genes, encoding morphological traits, pest and disease resistance, as well as 69 genes encoding enzymes. The development of molecular markers (RFLPs, AFLPs, SCARs and SSRs) has allowed the mapping of the apple genome and the development of several saturated genetic maps, to which genes controlling important traits are assigned. Markers flanking these genes not only play an important role in selecting parental combinations and seedlings with positive traits, but they are also particularly important in detecting recessive traits, such as seedless fruit. In addition they enable pre-selection for polygenic quantitative traits. In recent years, particular attention has been paid to biochemical and physiological processes involved in the pathway of important traits e.g., ripening and the storage capability of apple fruit

Tachinid (Diptera: Tachinidae) parasitoids of spotted ash looper (Abraxas pantaria) in Krka National Park in Croatia

Background and purpose: Spotted ash looper, Abraxas pantaria (Lepidoptera: Geometridae) causes defoliations of narrow-leaved ash (Fraxinus angustifolia) in Croatia, mainly in Krka National Park. Since controlling pests with insecticides is not possible in protected areas, biological pest control might be a valuable option. The first step in the study of its application is the research on hosts and their natural enemies. Not much is known about the parasitoid spectrum of A. pantaria in Croatia, so the aim of this research is to identify the parasitoid species which could influence the population density of this potential forest pest. Materials and methods: Pupae of A. pantaria were studied in 2010 at several locations along the River Krka in Krka National Park. This area was chosen because total defoliation of ash was observed in 2010. Results and conclusions: Five tachinid species were reared from Abraxas pantaria: Phryxe nemea, Bactromyia aurulenta, Senometopia sp., Pales pavida and Eurysthaea scutellaris. All species are generalist parasitoids. Phryxe nemea is the first record for this host

Identification of synthetic cannabinoid methyl 2-{[1-(cyclohexylmethyl)-1H-indol-3-yl] formamido}-3-methylbutanoate using modern mass spectrometry and nuclear magnetic resonance techniques

The samples of plant material suspected to contain new psychoactive substances are very often the subject of chemical-toxicological analyses. Gas chromatography-mass spectrometry (MS), liquid chromatography-quadrupole time-of-flight-MS, and liquid chromatography-tandem MS were applied with the aim to identify synthetic cannabinoid, methyl 2-{[1-(cyclohexylmethyl)-1H-indol-3-yl] formamido}-3-methylbutanoate (MMB-CHMICA) without the analytical standard, which is very often the case when a new drug arrives. The structure of compound was also confirmed by one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy and conformational analysis. After identification, methanolic extract of plant material containing MMB-CHMICA was successfully used for developing a multiple reaction monitoring method on liquid chromatography-tandem MS instrument. The optimization procedure is shown in detail. The complete fragmentation pattern and also the optimization of the extraction procedure of MMB-CHMICA from plant material were shown. The obtained data are useful for forensic, toxicological, and clinical purposes

Separation of rhenium (VIII) from tungsten (VI)

Examined were the conditions for an effective separation of tungsten(VI) and rhenium(VII) on alumina if the solution of 0.20 mol dm-3 NaCl, pH=2-6, is used as the aqueous phase. Under the given experimental conditions alumina was found to be much better adsorbent for tungsten than for rhenium. The breakthrough and saturation capacities of alumina at pH = 2 are 24 and 78 mg W/g Al2O3, respectively. With the increase of pH these values decrease. So, at pH = 6 they are only 4 and 13 mg W/g Al2O3, respectively. The elution volume for rhenium for the given column dimensions and the quantity of the adsorbent, is about 16 ml. These results were confirmed by the experiments of the radiochemical separations. Tungsten-187 remains firmly bound to alumina. The radionuclidic purity of the eluted 186,188 Re at pH = 2 is very high.Physical chemistry 2004 : 7th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 21-23 September 200

The effect of standarddose wintertime vitamin D supplementation on influenza infection in immunized nursing home elderly residents

Aim To investigate whether three-month oral vitamin D supplementation (800 IU in drops) reduces the risk of in - fluenza infection in elderly nursing home residents vacci - nated against influenza. Methods This cross-sectional observational study enrolled 97 participants (73.2% women) who received one dose of seasonal trivalent 2016-2017 influenza vaccine. The patients were randomized into an experimental group, which re - ceived vitamin D supplementation for three months start - ing on the day of vaccination, and a control group, which did not receive vitamin D supplementation. The primary outcome was the number of influenza infections labora - tory-confirmed using a rapid point-of-care test based on nasal swabs collected during vitamin D supplementation. The secondary outcome was serum 25-hydroxyvitamin D level at the end of the study. Results The mean age ±standard deviation was 78.5± 8.8 years. All participants had vitamin D deficiency at baseline. Twenty-three participants who developed signs of respira - tory infections during the study were tested for influenza virus. Although the number of influenza-positive partici - pants was lower in the group receiving vitamin D supple - mentation as compared with the control group (5 vs 12), this difference was not significant. Vitamin D supplemen - tation failed to increase 25(OH)D levels after three months of supplementation. Conclusion Elderly nursing home residents in Zagreb County have a significant vitamin D deficiency. The recom - mended national supplementation of 800 IU daily failed to lead to vitamin D sufficiency and did not reduce the risk of influenza infection among the vaccinated elderly

Uticaj BA i BA+GA4+7 na formiranje prevremenih grančica na jednogodišnjim sadnicama sorti jabuke

This study presents the influence of BA (6-benzyladenine) and BA+GA4+7 (6-benzyladenine + gibberellic acids 4 and 7) on feathering of one-year-old apple trees of two cultivars Jonagold and Čadel. Different concentrations of BA (300, 600, 1,200 and 1,800 mg L-1) and BA+GA4+7 (500, 1,000, 1,500 and 2,000 mg L-1) were applied, and two treatments for both chemicals were performed. The first treatment was applied at 70-cm height of nursery trees and the second 2 weeks later. Comparison was performed in relation to untreated control. An application of BA and BA+GA4+7 did not affect both rootstock and nursery tree diameter at 10 cm above the grafting union. Nursery trees of cultivar Jonagold were not influenced by treatments applied, whereas in cultivar Čadel, the treatment with BA+GA4+7 decreased apical growth of nursery trees. The development of sylleptic shoots in both cultivars tested was influenced by the type of growth regulator and concentration applied. Treatment with BA at 300 mg L-1 concentration in both cultivars tested did not influence total length and number of sylleptic shoots, as well as the number of sylleptic shoots longer than 20 cm. The most positive influence on all studied parameters was observed on nursery trees treated with the concentration of 1,200 mg L-1 BA. The lowest concentration of BA+GA4+7 (500 mg L-1) caused the low feathering of both studied cultivars. The higher concentrations (1,000, 1,500 and 2,000 mg L-1) similarly increased the number and total length of sylleptic shoots of nursery trees.U ovom radu je ispitivan uticaj BA (6-benziladenin) i BA+GA4+7 (6-benziladenin + giberelinska kiselina 4 i 7) na bočno grananje jednogodišnjih sadnica dve sorte jabuke Jonagold i Čadel. Primenjene su različite koncentracije BA (300, 600, 1.200 i 1.800 mg L-1) i BA+GA4+7 (500, 1.000, 1.500 i 2.000 mg L-1) pri čemu su kod oba hemijska jedinjenja tretmani izvedeni dva puta. Prvi tretman je izveden kada su sadnice bile visine 70 cm, a drugi tretman je izveden dve nedelje kasnije. Kontrola je bila bez tretiranja. Primena BA i BA+GA4+7 nije ispoljila uticaj na prečnik podloge i sadnice na visini od 10 cm iznad spojnog mesta. Kod sadnica sorte Jonagold nisu registrovane razlike u vršnom porastu pod uticajem primenjenih tretmana, dok je kod sorte Čadel tretman sa BA+GA4+7 uticao na smanjenje vršnog porasta sadnica. Ustanovljeno je da su tip hemijskog regulatora i primenjena koncentracija uticali na razvoj prevremenih grančica kod obe ispitivane sorte. Tretman sa BA u koncentraciji od 300 mg L-1 nije ispoljio uticaj na ukupnu dužinu i broj prevremenih grančica, kao i na broj prevremenih grančica dužih od 20 cm. Najpozitivniji uticaj na sve ispitivane parametre je zabeležen kod sadnica tretiranih sa BA u koncentraciji od 1.200 mg L-1. Najniža koncentracija BA+GA4+7 (500 mg L-1) je izazvala slabo grananje sadnica kod obe ispitivane sorte. Veće koncentracije (1.000, 1.500 i 2.000 mg L-1) su uslovile slično povećanje broja i ukupne dužine prevremenih grančica na sadnicama

Genotypic and Phenotypic Characterization of Stenotrophomonas maltophilia Strains from a Pediatric Tertiary Care Hospital in Serbia

Background Stenotrophomonas maltophilia is an environmental bacterium and an opportunistic pathogen usually associated with healthcare-associated infections, which has recently been recognized as a globally multi-drug resistant organism. The aim of this study was genotyping and physiological characterization of Stenotrophomonas maltophilia isolated in a large, tertiary care pediatric hospital in Belgrade, Serbia, hosting the national reference cystic fibrosis (CF) center for pediatric and adult patients. Methods We characterized 42 strains of cystic fibrosis (CF) and 46 strains of non-cystic fibrosis (non-CF) origin isolated from 2013 to 2015 in order to investigate their genetic relatedness and phenotypic traits. Genotyping was performed using sequencing of 16S rRNA gene, Pulse Field Gel Electrophoresis (PFGE) and Multi locus sequencing typing (MLST) analysis. Sensitivity to five relevant antimicrobial agents was determined, namely trimethoprim/sulfamethoxazole (TMP/SMX), chloramphenicol, ciprofloxacin, levofloxacin and tetracycline. Surface characteristics, motility, biofilm formation and adhesion to mucin were tested in all strains. Statistical approach was used to determine correlations between obtained results. Results Most of the isolates were not genetically related. Six new sequence types were determined. Strains were uniformly sensitive to all tested antimicrobial agents. The majority of isolates (89.8%) were able to form biofilm with almost equal representation in both CF and non-CF strains. Swimming motility was observed in all strains, while none of them exhibited swarming motility. Among strains able to adhere to mucin, no differences between CF and non-CF isolates were observed. Conclusions High genetic diversity among isolates implies the absence of clonal spread within the hospital. Positive correlation between motility, biofilm formation and adhesion to mucin was demonstrated. Biofilm formation and motility were more pronounced among non-CF than CF isolates