Automatic control for autonomous sailing boats

Avtonomne jadrnice so robotska plovila, ki brez potrebe po človekovih posegih uporabljajo veter za pogon in upravljajo z jadri in krmilom. Namen razvoja teh plovil je izdelava jadrnice brez posadke, ki omogoča popolno samostojno jadranje, varno plovbo in izvajanje dolgoročnih nalog na morju. Najpomembnejši sistemi avtonomnih jadrnic so: sistem za dolgoročno načrtovanje plovne poti v odvisnosti od vremenskih razmer, sistem za kratkoročno preusmerjanje jadrnice v odvisnosti od trenutnih podatkov iz senzorjev, sistem za izogibanje trkom in sistem za upravljanja s plovilom. Uporaba mehke (neizrazite) logike pri programiranju nadzornega sistema za upravljanje aktuatorjev se je izkazala za zelo primerno orodje za prenos ekspertnega znanja izkušenih jadralcev v računalniške programe v obliki preprostih pravil vrste ČE-POTEM. Cilj raziskav, predstavljenih v tem delu, je predlog novih nastavitev jader in aktuatorjev ter predlog sistema upravljanja, ki temelji na mehki logiki. Predlagamo razvoj avtonomne jadrnice s tremi različnimi sprednjimi jedri in možnostjo spreminjanja velikosti glavnega jadra. Možnost uporabe več jader v odvisnosti od vetrovnih pogojev in valov na morju podaljšuje obdobje najbolj učinkovitega delovanja (največje hitrosti) jadranja. Zaradi tega jadrnica z omenjeno postavitvijo jader prikazuje bolj realen model, ki se danes uporablja predvsem za oceanskega potovanja. Simulacije jadrnice s tremi različnimi sprednjimi jedri in možnostjo spreminjanja velikosti glavnega jadra so pokazale, da je uporaba mehke logike v nadzornem sistemu, ki upravlja z aktuatorji, smiselna in odpira možnost za razvoj hitrejšega, bolj stabilnega in energetsko učinkovitega plovila.Autonomous sailing boats are robotic vessels that use the wind to drive and can operate the sails and rudder without the need for human intervention. The purpose of the development of these vessels is constructing boats without crew, enabling full independent sailing, safe navigation and implementation of long-term tasks at sea. The most important systems of autonomous sailing boats are: long-term planning waterways, depending on weather conditions, short course routing depending on the current data from sensors, collision avoidance and control system for manoeuver execution. Using fuzzy logic for programming the control system for the management of the actuators, has proven to be a very suitable tool for the transfer of expert knowledge of experienced sailors in computer programs in the form of simple IF-THEN rules. The aim of the research, presented in this work, is to propose a new sails and actuators setting, and a management system based on fuzzy logic. We propose the development of an autonomous sailing boat with three different front sails and the possibility of changing the size of the main sail. The possibility of using different sail settings depending on wind and waves conditions at sea, extends the period of high performance (maximum speed) sailing. An autonomous sailing boat with this sail settings, represents a more realistic model of standard sailing boat used for ocean travel. Simulations of a sailing boat with three different front sails and the possibility of changing the size of the main sail, has shown that the use of fuzzy logic in the control system, that operates the actuators, is meaningful and opens the possibility for the development of faster, more stable and energy-efficient vessels

Enantioseparation of (±)-trans-β-lactam Ureas by Supercritical Fluid Chromatography

In this study the enantioseparation of (±)-trans-β-lactam ureas 1a–g by supercritical fluid chromatography (SFC) was examined using different polysaccharide based chiral stationary phases (CSPs), and CO2/alcohol (70:30, V/V) as the mobile phase. The influence of CSP type (coated or immobilized), modifiers (alcohols), additive (isopropylamine), temperature and backpressure on enantioseparation were examined. From five tested columns, only the column filled with tris-(4-methylphenylcarbamoyl) cellulose selector proved superior in terms of broad range substrate acceptability and selectivity. This work is licensed under a Creative Commons Attribution 4.0 International License

Comparative Study of 1,5-Dinitrogen Schiff Bases as Potential Ligands in Palladium-Catalyzed Allylic Alkylation

1-(2\u27-Pyrido and 2\u27-quinolino)-(1R)-arylethylamino)-ethylidenes (7–12) were prepared as potential ligands in PdII catalytic complexes for enantioselective allylic alkylation of 1,3-diphenyl-1-acetoxy-propene-2 (15). Alkylation with palladium complexes of 7–12 yielded 1,3-diphenyl-1-dimethylmalonyl-propene-2 (14) with enantioselectivity up to 55 % e.e. Enantioselectivity is discussed in view of the results recently reported for structurally related 1,5-bidentate dinitrogen ligands of C1 symmetry. Reversal of enantioselectivity observed for the ligands 10 and 11 is attributed to the inversion of steric requirements in the second coordination sphere of their catalytic complexes

Recent Achievements in Simulated Moving Bed (SMB) Technology. Part I.

Tehnologija simuliranog pokretnog ležaja poznata je više od pola stoljeća na području kontinuirane kromatografske separacije binarnih smjesa. Otkrivena i razvijena u petrokemijskoj i industriji šećera, ova tehnologija je prepoznata od strane organskih kemičara u farmaceutskoj industriji kao moćno oruđe za separaciju racemičnih smjesa. Niz godina razvijana je kao standardna laboratorijska metoda, zatim kao postupak za pilotna postrojenja, i konačno kao industrijska metoda za dobivanje kiralnih spojeva u optički čistom obliku. Konačni produkti ove tehnologije su enantiomerno čisti lijekovi te drugi biološki aktivni spojevi i njihovi intermedijari. U prvom dijelu ovog pregleda prikazani su osnovni principi i odabrani primjeri nedavne primjene tehnologije SMB.Simulated moving bed (SMB) technology is over half a century known in continuous chromatographic separation of binary mixtures. Invented and developed in the petrochemical and sugar industries, it was recognized by organic chemists in the pharmaceutical industry as a powerful tool in separation of racemic mixtures. Over the years, it was developed into a standard laboratory, then pilot-plant and finally large-scale method for production of chiral compounds in the optically pure form. Final products of this technology are enantiopure drugs, other biologically active compounds and their intermediates. In Part I of this review, the basic principles and selected examples of recent SMB technology applications are presented

Chemical profile of the organic residue from ancient amphora found in the Adriatic Sea determined by direct GC and GC-MS analysis

An ancient organic residue was collected from the bottom of a Greco-Italian amphora found in the Adriatic Sea and investigated by direct GC and GC- MS analysis. The headspace composition was determined by HS-SPME using: (1) DVB/CAR/PDMS and (2) PDMS/DVB fibres. Higher percentages of benzene derivatives, monoterpenes and other low- molecular aliphatic compounds were obtained by method (1) in contrast to higher percentage of naphthalene and phenanthrene derivatives found by method (2). In comparison with the composition of pine resin, it is more likely that the found low- molecular aliphatic alcohols, acids, esters and carbonyls with 2-phenylethanol were trapped and preserved within the organic residue from stored wine – the amphora’s originally content. Semi- volatile diterpenes methyl dehydroabietate (33.6%) and retene (24.1%) were dominant in the residue CH2Cl2 solution. Other abundant compounds were 1, 4-dimethoxyphenanthrene (6.8%) as well as other naphthalene and/or phenanthrene derivatives [7-(1- methylethyl)-1, 4a-dimethyl-1, 2, 3, 4, 4a, 9, 10, 10a- octahydronaphthalene, 7-(1-methylethyl)-1, 4a- dimethyl-2, 3, 4, 4a, 9, 10-hexahydrophenanthrene, 7- (1-methylethyl)-1, 4a-dimethyl-1, 2, 3, 4, 4a, 9, 10, 10a- octahydro-phenanthrene, 3, 6-dimethylphenanthrene and 2, 3, 5-trimethylphenanthrene]. Possible sources and formation pathways of the major compounds in the residue were discussed

Application of Green Chiral Chromatography in Enantioseparation of Newly Synthesized Racemic Marinoepoxides

Enantioseparation of the newly synthesized series of novel quinoline- 2(1H)-one epoxide structures rac-6a–c and rac-8a–c, named marinoepoxides, is described. Marinoepoxide rac-6a, the key intermediate in the total synthesis of natural products marinoaziridines A and B, as well as their structural analogues, was synthesized by addition of the achiral ylide generated in situ from the sulfonium salt 5 or 7, to the carbon-oxygen double bond of the corresponding quinoline-2(1H)-one-4-carbaldehyde 4a–c in good yield. Separation of enantiomers of (±)-2, 3, 3-trisubstituted marinoepoxides rac-6a–c and (±)-trans-2, 3-disubstituted marinoepoxides rac-8a–c was studied using two immobilized polysaccharide type chiral stationary phases (CSPs) ; tris-(3, 5- dichlorophenylcarbamoyl)cellulose stationary phase (CHIRAL ART Cellulose-SC) and tris-(3, 5-dimethylphenylcarbamoyl)amylose stationary phase (CHIRAL ART Amylose-SA). Enantioseparation conditions were explored by high-performance liquid chromatography (HPLC) using dimethyl carbonate/alcohol mixtures and n-hexane/ethanol (80/20, v/v) as mobile phase, and by supercritical fluid chromatography (SFC) using CO2/alcohol mixtures as mobile phase. In all examined racemates, enantioseparation was successfully achieved, but its efficiency largely depended on the structure of chiral selector and type/composition of the mobile phase

Enantioseparation of syn- and anti-3,5-Disubstituted Hydantoins by HPLC and SFC on Immobilized Polysaccharides-Based Chiral Stationary Phases

The enantioseparation of syn- and anti-3, 5-disubstituted hydantoins 5a–i was investigated on three immobilized polysaccharide-based columns (CHIRAL ART Amylose-SA, CHIRAL ART Cellulose-SB, CHIRAL ART Cellulose-SC) by high performance liquid chromatography (HPLC) using n-hexane/2-PrOH (90/10, v/v) or 100% dimethyl carbonate (DMC) as mobile phases, respectively, and by supercritical fluid chromatography (SFC) using CO2/alcohol (MeOH, EtOH, 2-PrOH ; 80/20, v/v) as a mobile phase. The chromatographic parameters, such as separation and resolution factors, have indicated that Amylose-SA is more suitable for enantioseparation of the most analyzed syn- and anti- 3, 5-disubstituted hydantoins than Celullose- SB and Cellulose-SC in both HPLC and SFC modalities. All three tested columns showed better enantiorecognition ability toward anti- hydantoins compared to syn-hydantoins, both in HPLC and SFC modes. We have demonstrated that environmentally friendly solvent DMC can be efficiently used as the mobile phase in HPLC mode for enantioseparation of hydantoins on the immobilized polysaccharide- based chiral stationary phases

Procjena nutritivnog potencijala i sadržaj specijaliziranih metabolita nekih vrsta agruma

The aim of this study was to assess the nutritional composition of fruits of some citrus species (sweet orange, grapefruit, clementine and kumquat) and to determine their basic physicochemical parameters, bioactive compounds content, and antioxidant capacity. According to the analyzed data, kumquat fruits had the highest dry matter content (18.71%) and total acid content (3.08%), while the highest values of total soluble solids (13.41%), pH value (3.92), vitamin C (53.69 mg/100 g FW), total phenols (162 mg GAE/100 g FW), β-carotene (1053.17 µg/100 g FW), and antioxidant capacity (1.70 mmol TE/kg) were determined in clementine fruits. Considering the nutritional composition of citrus fruits, it can be concluded that they are a rich source of various bioactive compounds, especially vitamin C, carotenoids, and polyphenols, and are characterized by their high antioxidant capacity, which is important for health. Moreover, the cultivation of citrus fruits is an important factor in the Croatian economy, which should be promoted in the future, and the potential of the southern part of Croatia for the cultivation of these citrus fruits should be exploited to the maximum.Cilj ovog istraživanja bio je valorizirati nutritivni sastav plodova određenih vrsta citrusa: slatke naranče, grejpa, klementine i kumkvata, analizirajući njihova osnovna fizikalno-kemijska svojstva, sadržaj bioaktivnih spojeva i antioksidacijski kapacitet. Prema analiziranim podacima, plodovi kumkvata imali su najviše vrijednosti ukupne suhe tvari (18,71%), ukupnih kiselina (3,08%), dok su istodobno u plodovima klementine utvrđene najviše vrijednosti topljive suhe tvari (13,41%), pH vrijednosti (3,92), vitamina C (53,69 mg/100 g FW), ukupnih fenola (162 mg GAE/100 g FW), β-karotena (1053,17 µg/100 g FW) i antioksidacijskog kapaciteta (1,70 mmol TE/L.) Temeljem analiziranih parametara nutritivnog sastava plodova različitih vrsta citrusa može se zaključiti kako su agrumi bogat izvor različitih bioaktivnih spojeva, posebice vitamina C, karotenoida i polifenola, pa ih stoga karakterizira i visok antioksidacijski kapacitet, a što je od iznimne važnosti i za zdravlje ljudi. Štoviše, uzgoj agruma važan je čimbenik u hrvatskom gospodarstvu, koji bi trebalo dodatno promovirati, dok potencijal južnog dijela Hrvatske za uzgojem ovih agruma treba maksimalno iskoristiti

Outcome of Pregnancy and Maternal Weight in Women Living in Coastal and Continental Croatia

Pregnancy outcomes are under the influence of maternal characteristics and environmental factors, diet being the most important. The benefits of the Mediterranean diet on all health indicators, including pregnancy, are well documented, placing at the top of the world’s healthiest diets. The aim was to investigate whether pregnant women living in the Mediterranean part of Croatia have better pregnancy outcomes in comparison to women living in the continental region. Observational longitudinal study was conducted in two Croatia’s regions: continental (city of Osijek and surrounding area) and coastal (city of Split and surrounding area). Even though women for the coastal region gained more weight during pregnancy (p=0.048) and prolonged gestation (p<0.001), maternal nutritional status has a higher influence on offspring’s nutritional status at delivery among women from the continental region. The incidence of pregnancy disorders (p<0.001) is higher among women from the continental region. Maternal weight prior to delivery was associated with caesarean section in both regions. Despite an unfavorable maternal nutritional status, both prior and during gestation and prolonged gestation, offspring’s nutritional status is better in the Mediterranean part of Croatia

Preterm births at the Department of gynecology and obstetrics, University hospital Split

Cilj: Prikazati odlike prijevremenih porođaja i nedonoščadi iz jednoplodovih trudnoća. Metode: Podaci za dvogodišnje razdoblje (2008. – 2009.) prikupljeni su popisnom metodom iz pisanih rađaoničkih protokola Klinike za ženske bolesti i porode KBC-a Split. Uključene su sve rodilje s prijevremeno rođenom novorođenčadi u ispitivanom razdoblju. Iz istraživanja su isključene višeplodove trudnoće, mrtvorođena i malformirana novorođenčad. Rezultati: Od ukupno 9 042 rođena novorođenčeta u Klinici za ženske bolesti i porode KBC-a Split tijekom dvogodišnjeg razdoblja kao nedonoščad je rođeno 436 (4,8 %). Carskim rezom rođena su 144 (33 %) nedonoščeta. Udio hipotrofične (11,6 % vs. 9,2 %; P = 0,113) i hipertrofične (7,3 % vs. 8,4 %; P = 0,438) novorođenčadi nije se razlikovao između nedonoščadi i terminske novorođenčadi. Ponderalni indeks nedonoščadi bio je manji u odnosu na terminsku novorođenčad (2,45 g/cm3 vs. 2,68 g/cm3; P < 0,001). Niska APGAR ocjena je trinaest puta češća (27,5 % vs. 2,1 %) u skupini nedonoščadi (P < 0,001). Zaključak: Učestalost rađanja nedonoščadi u Klinici ulazi u prosjek razvijenih zemalja svijeta, porođaji nedonoščadi povezani su s većom učestalosti carskog reza te nema razlike u učestalosti hipotrofije i hipertrofije nedonoščadi u odnosu na terminsku novorođenčad. Kod nedonoščadi je ponderalni indeks u prosjeku niži.Aim: This paper presents characteristics of preterm births and preterm infants from singleton pregnancies. Methods: The data refer to a 2-year period (2008-2009) and were collected from the birth protocol of the Department of Gynecology and Obstetrics, University Hospital Split. The study included all mothers with prematurely born infants. Multiple pregnancies, stillborn and malformed newborns were excluded from the study. Results: During the research period, 436 (4.8 %) of all infants (n = 9042) were born as preterm newborns. The caesarean section was performed on 144 (33 %) premature infants. The rate of hypothrophic (11.6 % vs. 9.2 %; P = 0.113) and hypertrophic (7,3 % vs. 8.4 %; P = 0.438) infants did not differ in preterm and term neonates. Ponderal index of preterm infants was lower (2.45 g/cm3 vs. 2.68 g/cm3; P < 0.001). Low APGAR score is thirteen times more frequent in the study group (27.5 % vs. 2.1 %; P < 0.001). Conclusion: The frequency of preterm birth in the Department is within the statistical average of developed countries. Preterm births are associated with higher rate of caesarean section with no difference in the frequency of occurrence of fetal hypotrophy and hypertrophy. In premature infants, ponderal index is significantly lower