30 research outputs found
NumeriÄko modeliranje zimske cirkulacije u TrÅ”Äanskom zaljevu (sjeverni Jadran)
Numerical simulations of the winter circulation in and around the Gulf of Trieste are presented. The model, based on the architecture of the Princeton Ocean Model, gave reasonable results for circulation in the Gulf during the winter period, when the dominant bora wind is blowing. Three model runs with different initial and surface boundary conditions show that there is an outflow along the shallow northern coastline of the Gulf and over the surface of the major part of the area, and an inflow at depth in the central and southern parts of the Gulf. However, the variability of the temperature and salinity fields when vertical fluxes of heat and salinity are present cause a weak outflow in an area near the southern part of the Gulf, and make the general circulation pattern more complex.Prikazana je numeriÄka simulacija zimske cirkulacije u TrÅ”Äanskom zaljevu i oko njega. ACOAST -1.2 model, baziran na āPrinceton Ocean Modelā i ugnježÄujuÄi se u model Å”ireg podruÄja, daje prihvatljive rezultate za cirkulaciju u zaljevu zimi, kada je bura dominantan vjetar.
Tri numeriÄka eksperimenta s razliÄitim poÄetnim i graniÄnim uvjetima pokazuju izlaženje vode u cijelom stupcu sjevernog plitkog dijela zaljeva i uz povrÅ”inu veÄeg dijela otvorenih granica, te kompenzacijski ulaz u donjem sloju srediÅ”njeg i južnog dijela. Promjene u poljima temperature i slanosti povezane s vertikalnim protocima topline i soli definiraju ovu kompleksnu sliku cirkulacije
Opažanja u obalnom podruÄju u okviru ADRICOSM projekta: TrÅ”Äanski zaljev
In the framework of the ADRICOSM project, from October 2002 to September 2003, a coastal observing system network was set up in the Gulf of Trieste. During this period, 36 CTD cruises were performed over a grid of 19 stations. An accurate data acquisition and quality check protocol was implemented for data decimation and smoothing. However, data analysis showed that conductivity/ salinity spikes were recorded at the depth of the very sharp thermocline observed in summer 2003. The exceptionally high salinity waters and the marked thermocline observed in the Gulf of Trieste in spring and summer 2003 directed us to compare the distributions of the temperature and salinity fields observed during ADRICOSM cruises with the available climatological values of the Gulf of Trieste, in order to assess whether the data collected during this research deviated significantly from the climatology.U okviru projekta ADRICOSM, od listopada 2002. do rujna 2003. godine, provedeno je 36 krstarenja tijekom kojih se uzorkovalo CTD sondom na 19 postaja u TrÅ”Äanskom zaljevu. Posebna pažnja je posveÄena kvaliteti podataka. Tijekom ljeta 2003. godine opaženi su nagli skokovi vrijednosti saliniteta i gustoÄe (tzv. āspikesā) u podruÄju izražene termokline. U proljeÄe i ljeto 2003. godine vrijednosti saliniteta bile su izrazito visoke. Polja temperature i saliniteta odreÄena za to razdoblje usporeÄena su s postojeÄim podacima ne bi li se utvrdilo koliko odstupaju od prosjeka
Smjernice za farmakoloÅ”ko lijeÄenje epilepsije
SAŽETAK
MeÄunarodne smjernice za farmakoloÅ”ko lijeÄenje epilepsija opÄenite su, sveobuhvatne i ne prepoznaju lokalne specifiÄnosti poput ekonomskih i tehniÄkih moguÄnosti u pojedinim državama, dostupnosti pojedinih antiepileptika ili drugih metoda lijeÄenja i sliÄno. Stoga se nameÄe potreba izrade nacionalnih smjernica, Äiji su zapravo temelj meÄunarodne smjernice Internacionalne lige protiv epilepsije. Hrvatske smjernice za farmakoloÅ”ko lijeÄenje epilepsija plod su suradnje svih relevantnih struÄnih druÅ”tava i referentnih centara u RH, na Äelu s Hrvatskom ligom protiv epilepsije te Hrvatskim neuroloÅ”kim druÅ”tvom i Hrvatskim druÅ”tvom za djeÄju neurologiju Hrvatskoga lijeÄniÄkog zbora, a odražavaju aktualne socioekonomske i regulatorne specifiÄnosti u naÅ”oj zemlji, najnovije spoznaje farmakoloÅ”kih profila i uÄinkovitosti pojedinih antiepileptika kao i ekspertna miÅ”ljenja. AntiepileptiÄka terapija se uvodi nakon postavljanja dijagnoze epilepsije, stoga profilaktiÄka primjena nije opravdana. Nakon postavljanja dijagnoze potrebno je bolesnika informirati o prognozi bolesti, moguÄnostima lijeÄenja i samopomoÄi, životnim ograniÄenjima te moguÄim neželjenim dogaÄajima. Ciljevi farmakoterapije epilepsija su potpuna kontrola napada uz izbjegavanje nuspojava te održavanje ili poboljÅ”anje kvalitete života. Zlatni standard lijeÄenja je monoterapija odnosno primjena adekvatnog antiepileptika u adekvatnoj dozi. Izbor i titracija lijeka su individualni, a temelje se na smjernicama za lijeÄenje pojedinih vrsta napada, karakteristikama bolesnika i regulatorno specifiÄnim Äimbenicima. Nakon neuspjeha inicijalne monoterapije, potrebna je reevalucija anamnestiÄkih i dijagnostiÄkih podataka te potom postupna i spora zamjena antiepileptika. Racionalna politerapija podrazumijeva kombinaciju dvaju antiepileptika razliÄitih mehanizama djelovanja, prvog ili eventualno drugog izbora za postavljenju dijagnozu, niskoga interakcijskog potencijala, razliÄitog profila nuspojava i sinergistiÄkog ili aditivnog djelovanja. Zamjena generiÄkih ili originalnog i generiÄkog oblika lijeka nije preporuÄljiva, a poglavito nakon postizanja remisije ili prilikom uzimanja visokih doza lijeka. Ukidanje antiepileptiÄke terapije treba biti postupno i sporo, u sluÄaju politerapije jedan po jedan lijek, a u donoÅ”enju odluke o ukidanju, kao i o uvoÄenju antiepileptika, mora biti ukljuÄen bolesnik i njegova obitelj
Multi-level directed graphs for analysis of spatial data
The dissertation provides a contribution to the field of spatial-temporal data mining, which is a response to the enormous amount of data collected in operational and research databases worldwide. The advantage of spatial-temporal data mining compared to traditional methods is the appropriate treatment of spatial and temporal attributes and consequently the ability to discover hidden information which is contained in databases.
The dissertation is limited to spatial-temporal data mining in the earth sciences, or more precisely, we have developed a methodology that upgrades methods of the Lagrangian particle tracking of moving virtual water parcels in the ocean. By using classic Lagrangian analysis, we examine paths or trajectories of simulated water parcels by visual inspection or by using various statistical methods as well as other approaches (i.e. dynamic system theory, stochastic modeling etc.). In the field of oceanography, which is the primary data source for the dissertation, high-quality numerical modeling is becoming increasingly important. Based on the velocity fields in the results of such a model, we first produce a number of trajectories of virtual particles (typically around 100,000). In the next step, we subdivide the model domain into smaller areas and search for spatial-temporal association rules that enable us to obtain the probability of the transition of virtual particles from individual sea areas to neighboring ones within the specified time interval. We visualize the resulting rules in the form of multi-level directed graphs with different granulation in space and time. We can add any attributes to the edges and vertices in such graphs, which represent aggregated or statistical information, or oceanographic or other material.
The resulting multi-level directed graphs are open to numerous algorithms that are used for graph mining. Our contribution is the algorithms for searching significant structures (paths and cycles) in these graphs. First we uncover simple cycles that occur in short periods of time (one month) within one graph, though more realistic paths and cycles occur over longer periods, that is, several months or even years. In the dissertation, we deal with paths and cycles that extend into periods of several months but less than one year. We deal with simulations which are too short to detect longer term processes and this results in dynamic paths. For the construction of these paths and cycles, we must take into account that the weights of graphs change over time, so the resulting paths and cycles are called dynamic. We perform hierarchical clustering of the resulting dynamic paths and cycles based on the distance between them and obtain dynamic fuzzy paths and cycles and compare them with the structures that are known from oceanographic observations provided by domain experts. The results in the dissertation show the significant similarity of obtained dynamic fuzzy paths and cycles with the observations and prior knowledge of oceanographic experts.
The methodology, described in the dissertation, is a solid basis for the development of applications that upgrade the established methods used by oceanographic experts. In chapter 6 of the dissertation, we present some examples of successful applications of multi-level directed graphs. Thus, we show that the movement of water masses in the Mediterranean Sea has a seasonal nature with a period of 12 months. In addition, by using multi-level directed graphs we present long-term transient phenomena such as the circulation reversal in the Ionian Sea, which occurs approximately every 10 years. By using additional attributes (e.g. wind power) in multi-level directed graphs, we show the correlation of the probability of movements of water masses with these attributes. Finally, multi-level directed graphs are a solid basis for modeling the dispersal of biological species
Comparative Analysis of Methods for Assessing the Effectiveness of Geological and Engineering Operations
The paper presents a comparison of the methods for assessing the baseline oil production level based on the use of nonparametric statistics, integral and differential models, and neural network algorithms
Comparative Analysis of Methods for Assessing the Effectiveness of Geological and Engineering Operations
The paper presents a comparison of the methods for assessing the baseline oil production level based on the use of nonparametric statistics, integral and differential models, and neural network algorithms
Climate circulation in the Gulf of Trieste (northern Adriatic)
The climatic circulation of the Gulf of Trieste, which is a shallow semienclosed basin in the closed northeastern end of the northrn Adriatic, is studied with a numerical model..