City Of Osijek Research Articles

The influence of oral hygiene in the preservation of oral health in the city of Osijek

The influence of oral hygiene in the preservation of oral health in the city of Osijek

A Comparative Analysis of the Spatial Configuration of Apartments Built in Osijek, Croatia, between 1930 and 2015

The main objective of this research is to identify spatial configurations that were dominant in apartment design from 1930 to 2015 in the city of Osijek, Croatia. Development of apartment design will be shown in the framework of various time periods following the social and economic changes that have taken place in Osijek in the last decades.For this research, a total of 590 apartment building plans were collected. The final sample contains 358 spatial configuration diagrams of medium-sized apartments.Results identified five different spatial configurations that were innovative for the period in which they appeared. The conclusion of the research is that the spatial layout of the apartment changes according to social and economic periods. Differences among types were identified in apartment functions organized by zones versus those organized by rooms; direct versus indirect inter-room communication; the appearance of specific room functions versus the integration of room functions; and growth versus decline of the net area of specific rooms. Results can be applied in further studies on improving and adapting the existing housing stock to contemporary housing requirements.

Evaluation of tramway overhead line system in city of Osijek

Overhead line system is a vital element of any electrified railway infrastructure. Its performance reflects to all vital parameters such as traction, reliability, availability and safety of railway infrastructure. Operator GPP Osijek runs a 27.5 km long tramway network which plays a key role in transit system of the city of Osijek, Croatia. In 2016 GPP Osijek applied to a tender for acquisition of new rolling stock with 85% EU investment. Mayor requirement prior to rolling stock acquisition was to document, analyse and upgrade current infrastructure (including track structure, electric substations and catenary) to an optimal level. Task of measurement and evaluation of tram track structure and catenary has been appointed to University of Zagreb Faculty of Civil Engineering. Overhead line analysis comprised from several measuring procedures, including supporting columns evaluation, catenary stagger, height, shocks and wear. Such extensive analysis included GPS positioning and on-site evaluation of 1214 supporting columns of overhead line, as well as overhead line measurements using an instrumented tram vehicle on 18 km of track. For conducting overhead catenary wire measurements, a tram pantograph has been fitted with equipment for measuring catenary height, accelerometers for shock measurement, camera, ruler and GPS for stagger measurement. Catenary wire wear was checked manually from catenary inspection vehicle. To conduct measurements, power had to be switched off on all electric substation along the route and tram vehicle had to be towed by a catenary inspection vehicle. All the data has been analysed and presented to end user in a user-friendly and intuitive GIS environment capable of further updates and detailed analyses. Evaluation of overhead line based on direct measurement results pointed out all the defects and weak spots on the system. It resulted in a series of recommendations for reconstruction and upgrade of the catenary system to fit the need of existing state and further development of tramway network.

Phytophilous Fauna of a Small and Artificial Urban Lake

Abstract Phytophilous community on Myriophyllum spicatum was studied in a small artificial urban lake in the city of Osijek (eastern Croatia), during the spring and summer season in 2010. In the eutrophic conditions, macrophyte stands were well developed and in the formed periphyton representatives of the following invertebrate taxa were found: Hydrozoa, Nematoda, Gastropoda, Cladocera, Copepoda, Insecta larvae - including families Chironomidae and Coleoptera. They displayed differences in temporal abundance patterns. Two separate phases in macrophyte colonization with differences in invertebrate composition and abundance were recorded. Insect larvae, particularly Chironomidae, were most abundant in the first phase, through the spring period, and Hydra oligactis (brown hydra) was most abundant in the second phase, i.e. summer period. Concurrently, microcrustacean abundance declined towards the end of the summer. Results of the analyses indicated that water temperature and perihyton biomass were the variables exerting the main influence on the invertebrate assemblage, while interestingly, macrophyte size and biomass were negatively correlated with most of the fauna abundance. On the other hand, brown hydra was negatively correlated with all other invertebrate taxa, except gastropods. Larger surface of submersed macrophytes is the main parameter supporting the increase of invertebrate abundance due to providing protection from predators and growth for periphyton, an important food source for these phytophilous organisms. Macrophyte length was positively correlated with Hydra abundance, while Chironomids were more influenced by periphyton biomass. These organisms can indicate water quality conditions and a potential increase in primary and secondary production.

Route Reliability Based Simulation Model for HMA Delivery in Urban Areas

Planning the delivery of hot mixture of asphalt (HMA) is challenging task, especially when the delivery routes pass through urban areas. Trend in development of recent planning and optimization models are simulation based. In this paper authors present a simulation model which is focused on routes’ reliabilities. As an optimization problem the model is structured as a combination of the well-known optimization problems (i.e. transportation and vehicle routing problem). The model was tested on a small scale case study problem of HMA delivery in city of Osijek. The results have proved that the model has the potential to become a useful planning and optimization tool for solving such problems.

Analysis of the Drava and Danube rivers floods in Osijek (Croatia) and possibility of their coincidence

The city of Osijek is situated on the right bank of the Drava River about 20 km away from its confluence with the Danube River. This good position was a prerequisite for its development, but throughout history, many floods caused by the Drava and Danube rivers have endangered Osijek and its citizens. Significant shortening of the river length by cutting meanders, river regulation structures together with the reduction in the natural floodplain were done during the nineteenth century. In the period between 1921 and 2013, there were 31 maximum annual water levels so high that flood warning systems were declared. The results of proposed hydrological analysis prove the presences of dominant Danube River backwater influences on flood occurrence in Osijek, especially in the last 40 years due to the decreasing trend of Drava River water levels and discharges and increasing trend of the Danube River water levels and discharges. The flood probability analysis shows (using a copula function) a very small probability of coincidence of maximum water levels in the Drava and the Danube, which is very important information for future flood risk management.

Comparison of different methods for ground thermal properties determination in a clastic sedimentary environment

Energy Strategy of the Republic of Croatia by 2020 relies on renewable energy resources as one of the main priorities. The use of geothermal energy sources is specifically encouraged. Within the research project “Research and the Promotion of the Use of Shallow Geothermal Potential in Croatia”, an improved method, the so called distributed thermal response test (DTRT) has been applied on a 100m deep borehole heat exchanger (double U pipe) within a borehole of 152mm outer diameter. The fundamental difference from the thermal response test (TRT) is the measurement of the carrier fluid temperature along the borehole heat exchanger (BHE) using an optic fiber cable placed inside the BHE pipes. Hence, in DTRT vertical distribution of the ground thermal conductivity and borehole thermal resistance are determined along the borehole heat exchanger. The undisturbed ground temperature profile along the BHE was also determined using this method. The work presented in this paper shows measurements from the borehole heat exchanger installation located in the city of Osijek, and determination of the ground thermal conductivity for specific geological settings using three different approaches: DTRT, TRT and direct measurement of sediment thermal properties. In a fluvial sedimentary sequence found in Osijek the discrepancy of DTRT and TRT results are 3.65% for thermal conductivity and 2.25% for borehole thermal resistance, while comparison of weighted averaged ground thermal conductivity results of DTRT and the direct thermal measurement yielded difference of 8.74%.

EXAMPLES OF TRAFFIC NOISE ABATEMENT IN THE CITY OF OSIJEK

Noise pollution is a major environmental problem in urban spaces worldwide. The first step toward noise abatement is determining and evaluating noise levels in order to best prioritize and implement protective measures. The city of Osijek, as is obligated by law and the European Directive, has done this by creating a noise map. In this paper, we present measures for noise abatement, showing some of the measures implemented in Osijek based on their noise map, and review possible methods for abating noise in the most vulnerable areas.

ASSESSING SEISMIC RISK IN RETFALA NOVA, OSIJEK

The Croatian territory, as part of the Mediterranean-trans-Asiatic belt, experiences pronounced earthquake activity. Seismic risk is the expected damage caused by earthquakes to buildings, measured both in social and economic losses, which can be described through seismic hazard, seismic vulnerability, and exposure. The city of Osijek is located in the eastern part of Croatia, and Retfala Nova is a residential settlement in the western part of the city. An important step in assessing earthquake loss is defining the exposure, so we created a form used to collect information on buildings and make a building database. In this paper, we estimated seismic vulnerability based on the capacity spectrum method, which involves constructing fragility curves and converting them to damage probability matrices, as well as constructing capacity curves.

EVALUATING THE AIRTIGHTNESS OF RESIDENTIAL BUILDINGS BY USING PREDICTIVE MODELS

A building’s energy consumption can be greatly reduced by improving its airtightness. Thus, when designing new and retrofitting existing buildings, it is important to accurately calculate energy losses caused by uncontrolled air leakage. A building’s airtightness can be measured by a pressurization test but only at the final stage of construction, and for large buildings this procedure can be very expensive and often produces results of questionable quality. Another way to evaluate airtightness is by using predictive models. In this study, we compare three predictive models for determining airtightness, using an airtightness database from buildings in the city of Osijek and in a suburban area. Using these models, we calculated airtightness values for 20 buildings and compared these predictions with measured results.

Spatial pattern of structural ageing in eastern Croatia: evolution and explanations

This article aims to examine the ageing situation and social policy issues in the Osijek-Baranja County of eastern Croatia. Using historical evidence from census data, research suggests that the evolution of the ageing pattern has been mainly determined by such factors as development of the transport system, changes in political-territorial organisation, supply of jobs in the cities, deagrarianisation and a domestic war in the 1990s. The increased importance of urban centres, through planned industrialisation and administrative centralisation, has accelerated and intensified rural-tourban migration. Consequently, the spatial pattern of structural ageing has been substantially affected. A significant variation was found in urban and rural areas and also within sub-regional units. The findings suggest that the evolution of spatial disparities in the ageing pattern is because of unplanned migration; spatial differences in the level of socio-economic development; the influence of tradition, such as higher fertility rates historically in some areas; and suburbanisation, notably around the city of Osijek. The article concludes that ageing is affecting the country’s economic growth and the formal and informal social support systems, including the provision of resources for older citizens in the endangered areas.

Demand side management in the distribution system with photovoltaic generation

In the last years, there was a great effort on inclusion electricity generation from the renewable energy sources in power system. Random renewable generation creates the imbalance between electricity production and consumption, which requires power plants with fast response and also storage systems. Generally accepted solution for load balancing is concept of smart grids and one of the elements of smart grid efficiency is the ability of real-time demand-supply balancing. In this paper, the model of the part of power distribution network of the city of Osijek has been created based on results of the power measurements of total electricity consumption in a family house in Osijek, air conditioning system consumption and PV power plant production. Also, algorithm for real-time load management is proposed. It assumes coordinated control of air conditioning system units depending on the production of PV power plants and electricity consumption of distribution network, in order to reduce peak demand in the distribution network.

COMPARISON OF CROATIAN AND EUROPEAN STANDARDS FOR DETERMINING THE FROST SUSCEPTIBILITY OF HYDRAULICALLY BOUND MIXTURES

The base layer of a multi-layered pavement structure is often a cement-bound material, which combines an aggregate with cement binder. This load-bearing layer is quite rigid, which improves pavement properties, including frost resistance, and extends the life cycle of the pavement. In geographic areas with low temperatures and significant ground water, the bearing capacity of pavement structures can be reduced by volume deformations from freezing and thawing. Cold winters and frost-susceptible soil are present in eastern Croatia and in the city of Osijek. Thus, in this paper we examine the frost susceptibility of cement-bound aggregates, made with materials commonly used in Croatia, in accordance with the current Croatian standard HRN U.B1.050 and a new European standard EN 13286-54. The test mixtures did not meet the conditions for frost-resistant materials. To meet these conditions, one must use a higher cement ratio or a cement with a higher strength class.

Comparison of Delays at Signal-controlled Intersection and Roundabout

Delays belong to standard parameters used for the evaluation of any type of intersection and they are taken in the evaluation of the level of service of an intersection. Intersections with shorter delays bring about economical benefits both for the users and the community, and enable greater efficiency of a traffic system, which is becoming a significant criterion with the increasing motorization. The case studies carried out in Europe and worldwide reveal that roundabouts bring delay savings if compared with other intersections of the same operational level and nearly the same traffic volume. The paper shows the results of the comparison analysis of the roundabout and the signal-controlled intersection in the city of Osijek, Croatia. The statistical indicators have given the basis for the evaluation of delays at the observed intersections, offering at the same time the possibility to compare the analysis conclusions on the local level with the conclusions of the case studies carried out throughout Europe and worldwide. KEYWORDS: delays, roundabout, signal-controlled intersection

The electrocoagulation/advanced oxidation treatment of the groundwater used for human consumption

The purpose of this work was development and application of the purification system suitable for the treatment of groundwater used for human consumption, satisfying following criteria: (a) no need for external addition of the chemicals; (b) simultaneous removal of wide range of contaminants present in the treated water; (c) low sensitivity to the changes in the composition of the treated water; (d) high quality of treated water with regards to all measured parameters. Therefore the well water from the 60 m deep water layer situated near the city of Osijek (Eastern Croatia) with elevated values of heavy metals, color, turbidity, suspended solids, ammonia and organic contaminants was processed. Due to the complex composition of the treated water, the purification system required the combination of electroreduction/electrocoagulation, using iron and aluminum electrode plates followed by the simultaneous ozonation/UV treatment. The electroreduction/electrocoagulation approach was used for the removal of heavy metals, suspended solids, color and turbidity, while the organic contaminants and ammonia were removed by the ozonation/UV treatment. All measured parameters in the purified water were significantly lower compared to the regulated values. Under the optimum treatment conditions, the removal efficiencies for color, turbidity, nickel and arsenic were 100%. The removal efficiencies of V, Cr, Mn, Fe, Cu, Zn, Pb, ammonia, fluorides, sulfates and COD were 94.5%, 96.0%, 98.3%, 99.6%, 99.7%, 97.8%, 96.7%, 96,7%, 93.4%, 51.4%, 72.2% and 93.8%, respectively, increasing with the increased initial concentrations.

Physiology and biochemistry of leaf bleaching in prematurely aging maple (Acer saccharinum L.) trees: I. Hydrogen peroxide level, antioxidative responses and photosynthetic pigments

Physiology and biochemistry of leaf bleaching in prematurely aging maple (Acer saccharinumL.) trees: I. Hydrogen peroxide level, antioxidative responses and photosynthetic pigmentsEssential signaling processes such as changes in calcium mobilization, protein phosphorylation and gene expression are known to be modulated by hydrogen peroxide (H2O2). A lot of silver maple trees in the city of Osijek (Croatia) were noticed to have bleached leaves by early summer as well as during the whole vegetation season. In this study we aimed to investigate the processes that regulate H2O2levels in healthy (green) and prematurely aged (bleached) leaves. For that purpose, photosynthetic performance and antioxidative response of green and bleached silver maple leaves were studied. Bleached leaves had higher hydrogen peroxide level, a three-fold level of total soluble proteins as well as a lower level of ascorbic acid. Concentrations of chlorophylla, chlorophyllb, total chlorophylls and total carotenoids as well as maximum quantum yield of photosystem II were lower in bleached leaves. This indicated their impaired photosynthetic performance. Further more, bleached leaves were characterized by lower specific activities of the main antioxidative enzymes, which influenced their reactive oxygen species scavenging capability. The higher level of H2O2content in bleached leaves as the consequence of reduced antioxidative enzyme specific activities as well as ascorbic acid level could be the reason for the down-regulation of photosynthetic performance and premature aging of those leaves.

KRUŽNA RASKRIŽJA – SUVREMENI NAČIN RJEŠAVANJA PROMETA U GRADOVIMA

Construction of roundabouts is intensified over the past 20 years in all European countries. Accordingly, those kinds of intersection are becoming more important in Croatia. The reasons for this are numerous advantages of a roundabout over the conventional intersections. Basic characteristics of roundabouts are traffic channelization, the possibility of connecting 4 or more junction roads and reduction of conflict points. This results in improved security and higher intersection capacity as their greatest advantage. There are five roundabouts built in the city of Osijek. As the existing roundabout proved to be useful and practical solutions, their number will increase in the near future. In this paper the basic characteristics of roundabouts and the specifics of roundabouts built in the city of Osijek are presented.

Effect of Surgical Training Course on Performance of Minor Surgical Procedures in Family Medicine Physicians’ Offices: an Observational Study

To examine the influence of a practical surgical course on the number of minor surgical procedures performed by family physicians. We compared the number of minor surgical procedures performed by family physicians in 59 offices in the city of Osijek and surrounding rural area during 12 months before and after the 40-hour practical surgical course held in September 2006 by surgeons and family medicine specialists. Minor surgical procedures taught in the course included management of ingrown toenails, abscesses/comedones, and minor wounds, anesthesia application, disinfection, use and sterilization of surgical instruments, and antibiotic treatment. The number of minor surgical procedures performed in family medicine offices almost doubled (503 vs 906 after the course, P<0.001, Wilcoxon test). The median number of abscesses/comedones treatments per physician increased from 1 to 6 (P<0.001, Wilcoxon test), the number of managed wounds increased from 111 to 217 (P<0.001, Wilcoxon test). The increase in ingrown toenail resections was also significant (from 120 to 186, P=0.004, Wilcoxon test). Fifty percent of physicians did not treat patients surgically, irrespective of the training. We found no association between the number of performed procedures and age, length of employment, or location of the physician's office (urban vs rural). However, we found that male physicians performed more surgical treatments both before and after the course (abscesses/comedones: P<0.001 and P=0.108 respectively; ingrown toenail resections: P=0.008 and P=0.008 respectively; minor wounds: P=0.030 and P<0.001; respectively). Practical courses can encourage practitioners to treat the patients surgically in their offices and, thus, increase the number of services offered in primary care. Female physicians should be more encouraged to perform minor surgical procedures in their offices.

Money on the Territory of the City of Osijek

There are several reasons, why money has been taken as the subject of study in this paper. Money is undoubtedly the most important part of monetary economy, but also of numismatics and notaphily. Money's cultural and artistic, as well as its economic dimension and some of the historic monetary solutions additionally emphasize its importance. The importance of money is also supported by the relative diversity, numerousness and specific gualities of particular monetary forms in a small geographic area, such as the territoiy of city, over a long period of time. The incorporation of some postulations of classical numismatics and notaphily into the science of money allows a more complete and a more comprehensive understanding of the phenomenon of money. Every possible initiative in terms of research, elaboration and presentation of unknown parts of monetary history of Osijek can present a challenge, but also an invaluable contribution to the study of monetary transactions of this city, as well as of Croatia.

SPATIOTEMPORAL MONITORING OF FLOODWATER MOSQUITO DISPERSAL IN OSIJEK, CROATIA

This paper demonstrates the possibility of using geostatistics to monitor the dispersal of mosquitoes for mosquito control programs at the municipal level. The case study objective was to quantify the dispersal of floodwater mosquitoes from the natural marshland Kopacki rit into the city of Osijek, Croatia, and to analyze the main factors controlling it. Fifty thousand adult Aedes vexans, Ochlerotatus sticticus, and Ochlerotatus caspius mosquitoes were marked with a powdered fluorescent pigment and released from the southern part of Kopacki rit on April 28, 2004. Forty CO2-baited Centers for Disease Control and Prevention traps were set in the area of the municipality of Osijek (171 km2) and were monitored for 10 days. A total of 582,471 mosquitoes were captured and examined in the laboratory. The mosquito counts from different sites were then interpolated using ordinary kriging and visualized dynamically to detect the dominant migrational directions. Mosquito dispersal and frequency were greatly influenced by wind speed (r = 0.82). The marked mosquitoes were found at 12 sites located from 1 km to 11.7 km away from the release point. The recapture rate was 0.044% (54% Oc. sticticus, 32% Ae. vexans, and 14% Oc. caspius). Based on the Lincoln index, the estimated total population size for floodwater mosquitoes in the study area ranged from 875 million to 2.0 billion mosquitoes. Limitations of the approach, recommendations for the improvement of the monitoring network, and spatial predictions are further discussed.