CONDITIONS AND POSSIBILITIES OF GEOTHERMAL ENERGY UTILIZATION FOR ECONOMIC-TOURISTIC DEVELOPMENT

Using thermal mineral water in various economic activities would reduce the need for conventional energy sources and increase complementarity and sustainability of the tourism business. Since the temperature of spring wells of Vranjska banja ranges from 63 °C to 95 °C, this paper deals with the possibilities of their use as a renewable energy source. The paper gives the results of water physical and chemical characteristics testing, the temperature and discharge of ten geothermal springs in Vranjska banja, respectively A-1, A-2, EX-2, EX-3, EX-2, B-1, A-3, B-2, Gornji source and a collecting drain. Test results show that the water contains a high concentration of fluorine (8–8.5 mg/l), the impact of which exhibits in the treatment of cancer, nervous system diseases, and a lot of respiratory diseases, arthritis and musculoskeletal disorders. Based on the results of the temperature and the abundance of the geothermal resources in Vranjska banja, the paper presents data on the heat capacity of the spa springs. The paper reports the results of the possibilities of using water springs of Vranjska banja water temperatures up to 25 °C and 37 °C in agriculture, industry, sports activities, etc. This article has been retracted. Link to the retraction 10.2298/IJGI181008004

Numerička studija udara kapljice u kose površine

Numeričke simulacije udara kapljice u kose površine su do nedavno bile ograničene na slučajeve kod kojih se uz mala odstupanja moglo pretpostaviti osnosimetrično strujanje. Mogučnost simuliranja asimetričnih dvofaznih strujanja korištenjem paralelnih računala i snažnog računalnog alata kao što je OpenFOAM bilo je glavni motiv za izradu ovog rada. Parametri koji opisuju proces udara kapljice u površinu zida su povezani sa vrijednostima određenim eksperimentalnim proučavanjem. Objašnjen je matematički model dvofaznog strujanja sa slobodnom površinom na kojem se temelji numeričko rješenje, opisane su prilagodbe aplikaciji interFoam koja strujanje rješava numerički, kao i aplikacija za obradu rezultata simulacija koja je izrađena u okviru rada u programskom jeziku C++. Usporedba rezultata eksperimenta i simulacija prikazane su u obliku dijagrama

Application of SVM Models for Classification of Welded Joints

Classification algorithm based on the support vector method (SVM) was used in this paper to classify welded joints in two categories, one being good (+1) and the other bad (−1) welded joints. The main aim was to classify welded joints by using recorded sound signals obtained within the MAG welding process, to apply appropriate preprocessing methods (filtering, processing) and then to analyze them by the SVM. This paper proves that machine learning, in this specific case of the support vector methods (SVM) with appropriate input conditions, can be efficiently applied in assessment, i.e. in classification of welded joints, as in this case, in two categories. The basic mathematical structure of the machine learning algorithm is presented by means of the support vector method

Diseases and faults of wine

Bolesti i mane vina izazivaju brojni mikroorganizmi- kvasci, plijesni ili bakterije, koji svojom životnom aktivnošću mijenjaju sastojke vina tako da kvare njihova organoleptička svojstva. Nisu svi mikroorganizmi krivi jer među njima ima i onih koji su neophodni za nastanak i normalan razvoj vina. Nepoželjnima nazivamo uzročnike bolesti i samo njima onemogućavamo prisutnost, aktivnost i opstanak u vinu. Najčešće bolesti vina su vinski cvijet, octikavost, zavrelica, manitno vrenje i sluzavost. Za razliku od bolesti, mane vina mogu biti posebno uzrokovane mikroorganizmima ili su posljedica nepovoljnih vremenskih prilika u doba dozrijevanja i berbe, a nerijetko posljedica nepažnje i neznanja. Najčešće mane vina su miris na sumporovodik, posmeđenje, crni, sivi i bijeli lom, okus po drvetu, bačvi,čepu, plijesni, peteljci ili neki drugi vinu strani okus ili miris. Prvi uvijet kvalitetne prizvodnje je zrelo i zdravo grožđe. Jednako je važna čistoća podruma, suđa i naprava, pravilna vinifikacija, promišljena upotreba sumpornog dioksida, stručna dorada i njega. Nekada bolesti i mane nije moguće liječiti; ponekad izliječena vina više ili manje izgube od svoje kakvoće pa je najbitnije da do pojave bolesti ili mane uopće ni ne dođe.Diseases and faults of wine are caused by many microorganisms – yeasts, molds or bacteria. They change the characteristics of wine by their activity in the way to spoil its organoleptic characteristics. Not all microorganisms are to be blamed for this because some of them are necessary for the production and normal development of wine. The unwanted ones are called so because they cause wine diseases, so we prevent their presence, activity and survival in wine. The most frequent wine diseases are flowers of wine, acetification, malolactic fermentation, mannite and slimy wine disease. As opposed to the diseases, faults of wine can be especially caused by microorganisms or unfavorable weather conditions at the time of maturing and grape harvesting. They also often appear as the consequence of negligence and lack of knowledge. The most frequent faults of wine are hydrogen sulfide smell, oxidative browning, black, grey and white diffraction, taste of wood, barrel, cork, mold, stalk or any other untypical taste or smell. The first condition of production of a good quality is ripe grapes. Clean basement, dishes and devices, proper vinification, cautious usage of sulphur dioxide, professional final processing and attendance are equally important. Diseases and faults sometimes can not be cured; it happens sometimes that cured wines lose somewhat of their quality, so it is most important that diseases or faults don’t happen at all

Five-Year Cumulative Incidence of Physical Inactivity in Adult Croatian Population: the CroHort Study

The aim of this study was to analyze gender and age differences in physical inactivity in Croatia and physical inactivity pattern changes during the five-year period. The study is based on the data obtained from the Croatian Adult Health Cohort Study which was carried out in 2003 and 2008. The prevalence of physical inactivity in 2008 was 37.7%, 36.8% in men and 38.1% in women. In both study waves the prevalence was increasing with age in both men and women. The prevalence is statistically significantly higher in subjects older than 64 years than in younger age groups. The incidence of physical inactivity in the five-year period in total was 29.9%, 27.2% in men and 31.1% in women. The increase in prevalence of physical inactivity despite the number of preventive activities carried out periodically emphasizes the need for systematic and comprehensive approach in increasing the number of regularly physically active individuals

Five-Year Cumulative Incidence of Physical Inactivity in Adult Croatian Population: the CroHort Study

The aim of this study was to analyze gender and age differences in physical inactivity in Croatia and physical inactivity pattern changes during the five-year period. The study is based on the data obtained from the Croatian Adult Health Cohort Study which was carried out in 2003 and 2008. The prevalence of physical inactivity in 2008 was 37.7%, 36.8% in men and 38.1% in women. In both study waves the prevalence was increasing with age in both men and women. The prevalence is statistically significantly higher in subjects older than 64 years than in younger age groups. The incidence of physical inactivity in the five-year period in total was 29.9%, 27.2% in men and 31.1% in women. The increase in prevalence of physical inactivity despite the number of preventive activities carried out periodically emphasizes the need for systematic and comprehensive approach in increasing the number of regularly physically active individuals

ANALYSIS AND EVALUATION OF DIMENSION STONE AND CRUSHED STONE AGGREGATE OF HERZEGOVINA (AND BEYOND)

Ovaj rad je nastavak radova objavljenih prije 10 godina koji su obuhvatili rezultate ispitivanja dobivene kroz razdoblje od 1997. do 2013. godine. Rad prikazuje rezultate ispitivanja dobivene kroz razdoblje od 2013. do 2023. godine. Autori temeljem znanstvene metodologije, korištenja relevantne literature kao i ispitnih laboratorijskih metoda analiziraju i vrjednuju dobivene rezultate ispitivanja prirodnog kamena kao elementarne sirovine za proizvodnju arhitektonsko-građevnog kamena (AGK) i tehničko-građevnog kamena (TGK). Rezultati ispitivanja temelje se na važećim ispitnim metodama. U radu su prikazana nalazišta prirodnog kamena za proizvodnju AGK i TGK, te rezultati ispitivanja njihovih fizikalno-mehaničkih svojstava kao osnovni kriterij za vrjednovanje.This paper is a continuation of papers published 10 years ago, which covered the tests results obtained during the period from 1997 to 2013. The paper presents the test results obtained during the period from 2013 to 2023. Based on scientific methodology, the use of relevant literature as well as laboratory test methods, the authors analyze and evaluate the obtained results of testing natural stone as a basic raw material for the production of dimension stone (DS) and crushed stone aggregate (CSA). Test results are based on applicable test methods. The paper presents natural stone deposits for the production of DS and CSA, as well as the results of testing their physical and mechanical properties as the basic evaluation criteria

A locally signed-distance preserving level set method (SDPLS) for moving interfaces

It is well-known that the standard level set advection equation does not preserve the signed distance property, which is a desirable property for the level set function representing a moving interface. Therefore, reinitialization or redistancing methods are frequently applied to restore the signed distance property while keeping the zero-contour fixed. As an alternative approach to these methods, we introduce a novel level set advection equation that intrinsically preserves the norm of the gradient at the interface, i.e. the local signed distance property. Mathematically, this is achieved by introducing a source term that is proportional to the local rate of interfacial area generation. The introduction of the source term turns the problem into a non-linear one. However, we show that by discretizing the source term explicitly in time, it is sufficient to solve a linear equation in each time step. Notably, without adjustment, the method works naturally in the case of a moving contact line. This is a major advantage since redistancing is known to be an issue when contact lines are involved (see, e.g., Della Rocca and Blanquart, 2014). We provide a first implementation of the method in a simple first-order upwind scheme.Comment: 18 pages, 5 figure