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Multirotors have proven their significance in fields like aerial imaging, surveying, and inspection. However, their effectiveness is hindered by limited flight autonomy due to the low energy density of standard lithium polymer batteries and high power demand. This necessitates frequent recharging, limiting prolonged operational capabilities. In response, our study introduces a methodology to assess the feasibility of a hybrid internal combustion engine and electric generator set as an alternative power source for multirotors. We investigate three theoretical multirotor designs tailored for mid-to-heavy load capacities (15 – 35 kg max take-off mass) and evaluate both pure battery and hybrid power as vehicle energy sources. Our findings indicate that hybrid power significantly enhances endurance, enabling extended flight times and wider range coverage. This extended aerial presence achieved with the hybrid system's superior endurance over traditional batteries significantly enhances multirotor capabilities, enabling innovative applications and expanded use cases.

Fragile X syndrome (FXS) is a global neurodevelopmental disorder caused by the expansion of CGG trinucleotide repeats (≥200) in the Fragile X Messenger Ribonucleoprotein 1 (FMR1) gene. FXS is the hallmark of Fragile X-associated disorders (FXD) and the most common monogenic cause of inherited intellectual disability and autism spectrum disorder. There are several animal models used to study FXS. In the FXS model of Drosophila, the only ortholog of FMR1, dfmr1, is mutated so that its protein is missing. This model has several relevant phenotypes, including defects in the circadian output pathway, sleep problems, memory deficits in the conditioned courtship and olfactory conditioning paradigms, deficits in social interaction, and deficits in neuronal development. In addition to FXS, a model of another FXD, Fragile X-associated tremor/ataxia syndrome (FXTAS), has also been established in Drosophila. This review summarizes many years of research on FXD in Drosophila models.

Species of the genus Alternaria are significant wheat contaminants during production, transport and storage, requiring biocontrol measures which typically rely on the bacteria from the Bacillus genera. As these are among the most beneficial and exploited biocontrol agents, in this study, the inhibitory activity of indigenous Bacillus spp. was as­sessed against the Alternaria alternata isolate originating from the wheat seed. Two of the fifteen Bacillus s pp. i ncluded i n t he s tudy s howed t he i nhibitory effect. Specifically, 25.0−55.0% inhibition of A. alternata growth was achieved when the isolate coded as NB11 was applied in 106−109 cells mL-1 concentrations. On the other hand, when applied in 107−109 cells mL-1 concentrations, the isolate coded as NB16 inhibited A. alternata growth by 35.2−51.1%, but was ineffective at lower concentrations. Thus, these in vitro assays indicate that both Bacillus spp. (NB11 and NB16) isolated from the wheat rhizosphere can be applied in practice in the control of A. alternata.

This research investigates the impact of various fertilization methods on the bioactive compound content and antioxidant activity of celery (Apium graveolens L.) root and leaf. Mineral fertilizer, poultry manure, cattle manure, sheep manure, supercompost, and molasses were applied. Total dry weight, phenolic and flavonoid compounds, and antioxidant activity were assessed, along with fiber, protein, fat, sugar, and starch in celery root. Principal component analysis (PCA) and cluster analysis were used to correlate production conditions with the parameters. The highest fiber and protein contents were found in mineral-fertilized roots, while total fat and sugar were highest in cattle-manure-fertilized roots, and starch was highest in supercompost-fertilized roots. Fertilization with supercompost yielded the highest total phenolic and flavonoid contents in leaves, while mineral fertilizer resulted in the highest antioxidant activity in roots. Notably, the highest dry weight in leaves and the highest total phenolic and flavonoid contents in roots were also observed with supercompost. PCA and cluster analysis demonstrated significant correlations between plant parts, i.e., the celery root and leaf samples, cultivation conditions, and the observed parameters, emphasizing the importance of selecting suitable cultivation methods to optimize celery’s nutritional properties. Also, these findings suggest that supercompost, a byproduct of breweries, could potentially replace animal-based organic fertilizers, addressing the problem of reduced availability due to declining livestock numbers.

Achieving sustainable economic growth is one of the main goals of economic policy in modern countries. As previous research has shown, the development of financial system has a significant influence on economic growth. The importance of the innovative banking sector in developing countries becomes particularly important due to the insufficient evolvent of other parts of the financial system. The subject of this paper is the analysis of the impact of the banking sector of Bosnia and Herzegovina on economic growth in the period from 2000 to 2021. The aim of the study is to quantify this relationship. In this study we apllied ARDL model to determine long-term and short-term relationship between observed variables. The results show that the increase in total loans granted by the banking sector to companies from the non-financial sector has a positive impact on the development of GDP. Namely, a 1% increase in total bank credit to non-financial private sector firms leads to an increase in GDP of about 0.08% in long run and about 0.20% in short run.

This paper presents a method for the estimation of key parameters of limit cycle oscillations (amplitude and frequency) during a relay experiment used for automatic tuning of proportional-integral (PI) and proportional-integral-derivative (PID) feedback controllers. The limit cycle parameter estimator is based on the first-order extended Kalman filter (EKF) for resonance frequency estimation, to which a second-order generalized integrator (SOGI) is cascaded for the purpose of limit cycle amplitude estimation. Based on thus-obtained parameters of the limit cycle oscillations, the ultimate gain and the ultimate period of the limit cycle oscillations are estimated. These are subsequently used for the tuning of PI and PID controller according to Takahashi modifications of Ziegler-Nichols tuning rules. The proposed PI and PID controller auto-tuning method is verified by means of simulations and experimentally on the heat and air-flow experimental setup for the case of air temperature feedback control. The results have shown that the proposed auto-tuning system based on relay control experiment for the heat and air-flow process PI/PID temperature control can capture the ultimate gain and period parameters fairly quickly in simulations and in experiments. Subsequent controller tuning according to Takahashi modifications of Ziegler-Nichols rules using thus-obtained ultimate point parameters can provide favourable closed-loop load disturbance rejection, particularly in the case of PID controller.

This paper deals with the control of the direct-current to direct-current (DC/DC) energy conversion between high voltage and low voltage systems within a hybrid electric power-train structure intended to be used in articulated forestry tractor, also known as skidder. Electrical part of the hybrid power-train is modeled for the case of utilization of a parallel array of step-down (buck) DC/DC power converters as a bridge between the high and low voltage DC buses. Thus obtained models are used to derive the control laws for the primary-level (power converter voltage/current) control systems, and the secondary level (power allocation) control strategy, which are simulated within the MATLAB/SimulinkTMsoftware environment, and subsequently verified by means of laboratory experiments. Final results are also used to gain insights about the efficiency of the DC/DC conversion process and to formulate practical rules for parallelized DC/DC converter operation aimed at maximization of overall DC-to-DC power conversion efficiency.

Poezija.

This article presents a review of cutting-edge technologies poised to shape the future of railway transportation systems, focusing on enhancing their intelligence, safety, and environmental sustainability. It illustrates key aspects of the energy-transport-information/communication system nexus as a framework for future railway systems development. Initially, we provide a review of the existing challenges within the realm of railway transportation. Subsequently, we delve into the realm of emerging propulsion technologies, which are pivotal for ensuring the sustainability of transportation. These include innovative solutions such as alternative fuel-based systems, hydrogen fuel cells, and energy storage technologies geared towards harnessing kinetic energy and facilitating power transfer. In the following section, we turn our attention to emerging information and telecommunication systems, including Long-Term Evolution (LTE) and fifth generation New Radio (5G NR) networks tailored for railway applications. Additionally, we delve into the integral role played by the Industrial Internet of Things (Industrial IoT) in this evolving landscape. Concluding our analysis, we examine the integration of information and communication technologies and remote sensor networks within the context of Industry 4.0. This leveraging of information pertaining to transportation infrastructure promises to bolster energy efficiency, safety, and resilience in the transportation ecosystem. Furthermore, we examine the significance of the smart grid in the realm of railway transport, along with the indispensable resources required to bring forth the vision of energy-smart railways.

By relying on Michel Foucault’s theory of social discourse and power/ knowledge where culture, customs and other elements of society are seen as the source of shared knowledge imposed on the individuals, this paper explores the theme of violence in William Faulkner’s novel Light in August (1932) to prove Joe Christmas’ violence as the result of his exposure to the social discourse of the time he lives in, namely the South during the Jim Crow era. The paper proves violence in the novel as mostly connected to the character of Joe Christmas and explores why Joe Christmas, even though the main enactor of violence, is not regarded as a villain but as an anti-hero. The period in which Christmas lives is the Jim Crow South where blackness was regarded as inferior, negative and evil which affects Joe’s self-perception and his actions. Joe, the captive of society, exhibits violence because the only thing he has been thought is to respond with violence. The paper will analyze several parts of the novel connected to Joe Christmas and violence to prove how violence in Faulkner’s novel does not exist per se but serves to prove how damaging the effect of society and social discourse can be.

Background/Aim. Coronavirus disease 2019 (COVID-19) is a predominantly respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The aim of this study was to determine whether there were parameters that could predict the development of a severe clinical picture and fatal outcomes in COVID-19 patients. Methods. The study involved 632 patients treated at the Clinic for Infectious Diseases, University Clinical Center Kragujevac, from June 2020 to February 2021. All patients were divided into two groups according to the need for oxygen therapy (Sat 02 < 94 %). Results. Our results showed that high body mass i ndex (BMI) was singled out as a risk factor for the development of a severe clinical picture (BMI, ORadjusted = 1.263; 95% CI = 1.117 – 1.427; p < 0.001). Prothrombin time (ORadjusted = 1.170; 95% CI = 1.004 - 1.364; p = 0.045), as well as low albumin values (ORadjusted = 0.878; 95% CI = 0.804 - 0.958; p = 0.003), had a predictive signifi-cance for the development of a severe clinical picture. Fac-tors that were of predictive importance in patients with fatal outcomes were C-reactive protein (CRP) (ORadjusted = 1.010; 95% CI = 1.001 – 1.019; p = 0.031), lactate dehydrogenase (LDH) (ORadjusted = 1.004; 95% CI = 1.001 – 1.006; p = 0.002), and X-ray of the lungs (ORadjusted = 1.394; 95% CI = 1.170 – 1.661; p < 0.001). Conclusion. The study showed that routine, clinical laboratory parameters can be important in the early detection of patients with a potentially severe clinical picture and fatal outcomes. In patients with a mild clinical picture, CRP, LDH, ferritin, and serum albumin levels may timely indicate disease progression. Monitoring these parameters is of essential importance for the timely clinical assessment of patients with COVID-19 and, thus, the prompt application of adequate therapeutic protocols in the treatment of these patients.

Social entrepreneurs create value. Global problems such as poverty have been heightened by the economic crisis lately and continue to affect the lives of many people all over the world and bring a great deal of interest to the social economy. Social entrepreneurship is an important determinant of the social economy and describes a set of exceptional behaviors. This paper analyzes the notion, perception, and degree of social-economic development with an emphasis on social entrepreneurship in the selected countries of the European Union and Croatia. The analysis encompasses the concept and development of selected older members of the European Union and relies on post-socialist countries at the same time as the newest members of the European Union. By analyzing the facts it is trying to prove that the social economy and social entrepreneurship are more developed and more fragmented in the older and more developed countries of the European Union. Further evidence of this fact is the level of employment in the social economy in the European Union, where the post-socialist countries lag behind the more developed countries of the European Union.

The increase in interest rate is related to the efforts of monetary authorities to neutralize inflationary pressures; while the rate reduction can be interpreted as an invitation to business sector to access more favorable lending conditions. The effectiveness of these changes largely depends on the development level of financial system, the role of the central bank as a creditor and current economic situation. In this research an econometric regression double-logarithmic model was applied, with the main goal of examining the relationship between discount rate and its influence on interest rates and money supply on the example of the National Bank of Serbia. The results show the correlation between the NBS discount rate and interest rates of commercial banks and the amount of money in circulation, indicating their influence on market stability.

The paper presents research results of efficiency of tourism sector in certain European countries and regions obtained by applying DEA method. The primary goal of the paper is to determine to what extent tourism sector in certain European countries and regions is efficient in relation to set parameters, while the secondary goal is aimed at providing recommendations for its improvement. In relation to this, the methodology of the DEA analysis is based on the input and output parameters which were used to determine the efficiency. The input parameters included: number of hotels and similar accommodation capacities, number of rooms and number of bed places, whereas the output parameters included: number of inbound tourists, number of bed-nights and tourism expenditure during their stay abroad. One of the conclusions of the paper is that the total efficiency was shown in Croatia, Belgium, and Denmark, while the technical efficiency was also present in North Macedonia, France, Malta, the Netherlands, Portugal, and Spain.

During the foundation period of Zagreb’s Gradec and Opatovina, a specific architectural type of wooden single-storey residential house emerged, the so-called purgerska hiža, based on the traditional wooden architecture of the wider Zagreb area, which has been defined, for the first time in this paper, as the Zagreb traditional wooden house. Features of this house type can be recognised in brick residential houses from the 18th century onwards, both in Opatovina and Gradec, and they became a staple piece of architecture commissioned by the economically less powerful and less educated. This paper describes the prominent features of this architectural type, as well as the specificities of a more elaborate type of two-storey house that developed therefrom. Here it is shown that this type continued in the brick form long into the 19th century, and that certain features occasionally cropped up even in the 20th century. All Upper Town and Opatovina houses that can be subsumed under this type have been identified in this paper, as well as houses derived from that type, which can be considered its modifications, and they have been analysed in order to determine where the influences on this type of architecture had come from, adopting a new thesis on Zagreb as a border zone that was influenced by two ethnographic regions: Turopolje and Hrvatsko Zagorje.

This paper presents the novel design of a constant-current/constant-voltage charging control strategy for a battery cell. The proposed control system represents an extension of the conventional constant-current/constant-voltage charging based on the so-called cascade control system arrangement with the adaptation of the battery charging current based on the open-circuit voltage parameter estimation. The proposed control strategy features two feedback controllers of the proportional-integral type responsible for: (i) controlling the battery open-circuit voltage towards its fully charged state, and (ii) simultaneously limiting the battery terminal voltage to avoid the battery terminal voltage constraint violation. The open-circuit voltage on-line estimation is implemented by using the system reference adaptive model approach to estimate the linear time-invariant battery equivalent circuit model parameters, whose asymptotic convergence is guaranteed according to Lyapunov stability theory. The proposed concept of the battery charging control is verified by means of simulations using the experimentally obtained model of a lithium iron phosphate battery cell, and it is also compared to other charging methods with respect to charging speed-up potential compared to conventional charging. The proposed method, which can be easily extended to conventional chargers, results in 23.9% faster charging compared to conventional charging, thus representing an inexpensive and straightforward upgrade to conventional battery charging systems.

This paper presents the use of track condition data from the virtual remote wireless sensor network within a simulation model of a battery-hybrid diesel-electric locomotive-driven freight train for a realistic mountain railway route simulation scenario. Simulation model includes the point-mass model of freight train longitudinal motion dynamics subject to wheel-to-track adhesion and head wind variations, the model of hybrid diesel-electric locomotive energy efficiency, and the model of real-time information provide to the virtual train driver about railway track conditions based on a narrow-band wireless remote sensor network. Simulation results are used to assess the possible benefits remote wireless sensor data for freight train energy-optimal control and to increase the transportation safety, including prediction of possible delays due to changed weather conditions en route.

The analysis of monetary variables and their impact on the economic growth rate has always been in the focus of economic research. In the broadest sense, economic theory distinguishes two basic views defined by the views of monetarists and Keynesians. Although the basic difference is reflected in the determination of price rigidity and money neutrality, specifics of modern economic systems shift the focus towards the positive influence of monetary on real variables. The aim of our research is to identify and quantify the impact of monetary variables on economic growth in Bosnia and Herzegovina. The research was conducted using data from the period 2000-2020. The paper starts with the hypothesis that money supply and inflation ultimately have a positive impact on the real economic growth in BiH. The money supply M2 and the annual inflation rate are taken as explanatory (monetary) variables in the research, while real growth is a dependent variable. The long-term relationship between monetary variables and real growth rates was tested, taking into account the specificity of the BiH monetary arrangement established in the form of a currency board. In order to prove the hypothesis, we applied econometric techniques such as VEC model, cointegration analysis, innovation analysis based on the impulse-responsive function, decomposition variance as well as a causality test. The research results showed the connection between the money supply and the inflation rate with the economic growth in BiH, the relation being positive and statistically significant in the long run. With this, we confirmed the initial hypothesis of the work.

Hybrid electric propulsion, using batteries for energy storage, is making significant inroads into railway transportation because of its potential for notable fuel savings and the related reductions in greenhouse gases emissions of hybrid railway traction over non-electrified railway lines. Due to the inherent complexity of hybridized powertrains, combining different power conversions and energy storage capabilities, the corresponding operation of their energy management needs to be precisely optimized in order to achieve the minimum possible fuel consumption. Having this in mind, this paper proposes a real-time energy management control strategy for a diesel–electric hybrid locomotive based on the optimization results obtained by means of a dynamic programming optimization algorithm aimed at fuel consumption minimization while honoring the battery state-of-charge constraints and powertrain physical constraints. The final optimization result, expressed in terms of the optimal battery state-of-charge reference (target), is used as an additional input into the state-of-charge controller within the real-time energy management system. The subsequent simulation analysis shows clear fuel economy improvement with 22.9% of fuel savings obtained for the locomotive featuring a hybrid powertrain equipped with batteries over the conventional one.

Social media represents a global phenomenon that has a great influence on society, primarily in terms of opportunities for new ways of communication that found wide application in modern business. In that sense, the paper analyzes the complex situation between social media communication and tourism. Main goal of the paper is identifying and defining the role that social media have in contemporary tourism. Methodology in the paper, related to contemporary tourism business includes: defining and analyzing social media with special emphasis on their advantages and disadvantages, then analysis and determining the importance of strategic online communication and finally identifying and analyzing the characteristics of individual social media that are of the greatest importance in this strategic process. One of the research conclusions is that the strategic approach of social media and online communication represents one of the key activities in modern tourism business. The set research goal was fulfilled through research analysis, i.e. the role of social media and strategic online communication in modern tourism business was determined, as well as characteristics of social media that have the greatest impact on it.

Corporate social responsibility, as a business philosophy and managerial concept, is increasingly represented in contemporary business operations and marketing, as well as in the scientific literature in this field. The importance that consumers attach to different aspects of social responsibility when evaluating companies and products and making purchasing decisions, is determined by economic, sociological, institutional and technological development of the environment, differing in developed countries and emerging markets. The aim of this paper is to investigate how consumers perceive the responsibility of companies operating in the market of the Republic of Serbia and which aspects of social responsibility they perceive as crucial or more important. In order to examine how consumers perceive the social and environmental dimensions of corporate social responsibility, an empirical study was conducted, using the survey method. For the purposes of the research, the questionnaire was adapted from the similar studies in foreign countries, which enables a comparison of the importance of different dimensions of corporate responsibility with consumers from different markets. In addition to standard demographic questions, the questionnaire also contains questions related to different perception, beliefs and attitudes, as well as expectations of respondents' in relation to the social and environmental dimension of company responsibility. The results of the research showed that there is a significant correlation between the perception of environmental and social aspects of corporate social responsibility and consumer preferences, expressed in company's evaluation and intention to buy its products or services. One of the conclusions of the survey is that demographic characteristics of respondents determine this connection.

The fulfillment of belonging needs underlies a variety of behaviors. In order to understand how social needs unmet during maturation shape everyday life, we examined social motivation and cognition in peripubertal rats, as a rodent model of adolescence, subjected to social isolation (SI) during early and early-to-mid adolescence. The behavioral correlates of social orientation (social space preference), sociability (preference for social over non-social novelty), and social novelty preference (SNP) were examined in group-housed (GH) and single-housed (SH) rats in a 3-chamber test. The response to social odors was examined to gain insights into the developmental role of social odors in motivated social behavior. Differentiation between appetitive (number of visits/approaches) and consummatory (exploratory time) aspects of motivated social behavior was done to determine which facet of social motivation characterizes maturation when social needs are met and which aspect dominates when social needs are unsatisfied. The SI-sensitive parvalbumin-expressing interneurons (PVI) in the hippocampus were examined using immunohistochemistry. The main findings are the following: (1) in GH rats, the preference for social space is not evident regardless of animals’ age, while sociability becomes apparent in mid-adolescence strictly through consummatory behavior, along with complete SNP (appetitive, consummatory); (2) SH promotes staying in a social chamber/space regardless of animals’ age and produces an appetitive preference for it only in early-adolescent animals; (3) SH promotes sociability (appetitive, consummatory) regardless of the animals’ age and prevents the SNP; (4) the preference for a social odor is displayed in all the groups through consummatory behavior, while appetitive behavior is evident only in SH rats; (5) the response to social odors does not commensurate directly to the response to conspecifics; (6) SH does not influence PVI in the hippocampus, except in the case of early-adolescence when a transient decrease in the dentate gyrus is observed. These results accentuate the developmental complexity of social motivation and cognition, and the power of SI in adolescence to infringe social maturation at different functional levels, promoting appetitive behavior toward peers overall but harming the interest for social novelty. The findings emphasize the importance of the fulfillment of basic social needs in the navigation through the social world.

Background: Cryptocurrencies represent a specific technological innovation in financial markets that keeps getting more and more popular among investors around the world. Given the specific characteristics of the cryptocurrencies, this paper examines the possibility of their use as a diversification instrument.

The aging of European societies is reshaping their population pyramids. The increase in life expectancy and the decrease in the fertility rate lead to an increasing share of the elderly population. This leads to rising age-related expenditures, especially public pension expenditures to GDP. Consequently, economies are reforming their pension systems to make them more sustainable. Next to the aging-related challenges, the new EU members, eleven post-socialist economies: Bulgaria, Croatia, the Czech Republic, Estonia, Hungary, Latvia, Lithuania, Poland, Romania, Slovakia, and Slovenia share a similar history of restructuring of their pension systems and establishment of a multi-pillar system. The objective of this article is to examine the similarities and differences between the pension systems of the selected post-transition economies of the European Union to establish the basis for further research, simulations, and assumptions on the impact of future pension reforms. For that purpose, we apply Ward’s clustering methodology on three variable groups in three selected years: 1996, 2006, and 2016. The idea of clustering economies in three years with a 10-year gap is relevant since it reveals how the cluster structure is changing over time. Additionally, three periods represent three different phases in the pension systems’ development. Three groups of variables were used for cluster analysis. First, pension systems’ characteristics include average effective retirement age, pension expenditure, and replacement rate. Second, demographics encompass fertility rate, life expectancy at the age of 65, net migration rate, and old-age dependency ratio. Third, the macroeconomics and labour market variables refer to the GDP growth rate, real labour productivity, labour force participation rate, and the unemployment rate. Results of cluster analysis show that the composition of the countries in the extracted clusters changes significantly, both throughout the observed period and when looking at different variable groups. Our results revealed that the pension systems of economies with later retirement proved to be more sustainable, during the three observed periods, due to lower pension expenditures that are in turn positively reflected in the favourable economic conditions and their labour market.

Until now, morphological trait variation has been investigated in several millipede species using geometric morphometrics. The present study is the first attempt to explore sexual shape and size dimorphism (SShD and SSD) of morphological structures in Polydesmida. We here analyse antennal, head, and leg SShD and SSD in Brachydesmus troglobius Daday, 1889. Our results show that SSD exists in all of the analysed structures, while SShD is present only in the legs. In comparison with females, males possess longer and wider legs, as well as longer antennae and a shorter head. Contrary to previous findings in some Julida, in B. troglobius SSD of the antennae and legs varies more than SShD in these morphological structures.

This paper presents a control system design methodology for the drill-string rotary drive and draw-works hoist system aimed at mature drilling rig retrofitting. The rotary drive is equipped with an active damping speed control system featuring a proportional-integral speed controller readily available within modern controlled electrical drives, extended with drill-string back-spinning prevention scheme for the case of stuck tool. The draw-works hoist system features a tool normal force (Weight-on-Bit) controller with tool longitudinal speed (Rate-of-Penetration) limiting functionality. The design of proposed control systems has been based on suitable control-oriented process models and damping optimum criterion which guarantees a desired level of closed-loop system damping. The proposed drilling control systems have been verified on a downscaled laboratory experimental setup, which represents a necessary pre-requirement before these systems are tested in the field.

Hybrid powertrain presents a viable solution for reducing fuel consumption through powertrain electrification while simultaneously being independent from the electric grid or a charging station. Due to the fact that articulated forestry tractors (skidders) belong to the class of forestry machinery which is intended for field use, this operating independence is of high importance. A simple backward-looking model of a series hybrid powertrain skidder is developed and presented in this paper. The model is then optimized over a number of previously-defined operating missions which include realistic track slopes and variable loads. The results are compared with the results of conventional and parallel hybrid powertrains proposed in previous works. Optimization results show that total fuel consumption obtainable with the proposed series configuration over the parallel one is slightly higher (the total efficiency of series structure is slightly lower) when compared to the parallel structure. Therefore parallel configuration can be considered as optimal soulution.

The implementation of renewable energy sources and heat pumps with natural refrigerants in the existing 3rd-generation district heating (DH) systems is a promising technology for the conversion to a 4th-generation DH system. This paper aims to investigate this transition through a case study for the existing DH system in Croatia. The district of Rijeka, which is considered in the case study, has an existing 3rd-generation DH system with a capacity of 9.2 MW, which was originally designed for a temperature regime of 130/70 °C and produces thermal energy from natural gas. In order to use heat pumps efficiently in such a system, the temperature of the distribution system and the energy consumption should be reduced. Trnsys software was used to perform complete dynamic simulations of the DH system. Used baseline models were validated according to the actual energy consumption reported by the heat supplier. The application of heat pumps with natural refrigerants in combination with on-site electricity production (PV system) can almost eliminate system CO2 emissions, reduce primary energy consumption and lower operation costs. Simulations were performed for 18 different scenarios that included 2 different building envelope variants. The results were compared, then discussed and conclusions were drawn.

Solar heating and cooling (SHC) systems are currently attracting attention, especially in times of increasing energy prices and supply crises. In times of lower energy prices, absorption SHC systems were not competitive to compression cooling supported by photovoltaic (PV) modules due to the high investment costs and total energy efficiency. This paper aims to discuss the current changes in energy supply and energy prices in terms of the feasibility of the application of a small absorption SHC system in a mild Mediterranean climate. The existing hospital complex restaurant SHC system with evacuated tube solar collectors and a small single-stage absorption chiller was used as a reference system for extended analysis. Dynamic simulation models based on solar thermal collectors, PV modules, absorption chillers and air-to-water heat pumps were developed for reliable research and system comparison. The results showed that primary energy consumption in SHC systems designed to cover base energy load strongly depends on the additional energy source, e.g., boiler or heat pump. Absorption SHC systems can be price competitive to air-to-water heat pump (AWHP) systems with PV collectors only in the case of reduced investment costs and increased electricity price. To reach acceptable economic viability of the absorption SHC system, investment price should be at least equal to or lower than a comparable AWHP system.

The pretension of this paper is to process Camp in all its aspects and possible areas of application. The process begins with the analysis and interpretation of Lexicographic definitions of Camp and, close concepts to it by meaning (kitsch and Trash), followed by the interpretation and revaluation of still the most important text on Camp – Notes on Camp by Susan Sontag. Following that, the paper seeks to provide a general definition of Camp that seeks to determine, describe and indicate the boundaries of its scope. The paper revises the postulate of certain theories on Camp: firstly, only those on its gay character and its power for political subversiveness. Camp taste/sensibility/style also strives to be contextualized within the framework of fine arts on examples of certain stylistic formations and author poetics of some of the exemplary artists that belong to them, in order to provide a paradigm for the interpretation of their opus applicable to other artistic opus.

A potential relationship between unrestricted sucrose intake (USI), overweight, and emotional/behavioral control has not been well documented. We examined the influence of USI and having less sweetness than expected on body weight (BW), motor/exploratory, anxiety-like, and social dominant behavior in adult C57BL/6J male mice. Animals had free access to water (group 1) or 32% sucrose and water (sucrose groups 2–5) for 10 days. Then, group 2 remained with 32% sucrose while groups 3–5 were subjected to the downshift (24 h access to 4%, 8%, or 16% sucrose). All experimental groups were weighed and tested in the novel-open arena (NA), elevated plus maze (EPM), and tube tests to assess BW, motor/exploratory, anxiety-like, and social dominance behavior, respectively. USI did not influence animals’ BW but produced hyperactivity and anxiolytic-like behavior, which was evident in EPM but not in NA; the outcomes of the downshift were comparable. USI did not influence successes/wins in the tube test but altered emotions that drive the winning, favoring a less anxious behavioral phenotype; this was not evident in the downshifted groups. Observed findings suggest that USI promotes sensation-seeking and motivates dominance, without changing BW, while blunted emotional base of social dominance might be an early mark of the downshift.

High worldwide prevalence of steel in the construction of buildings and infrastructure is associated with high costs that are due to the sensitivity of steel to corrosion. To reduce the steel structure corrosion protection costs, great efforts are currently made to develop new technologies that would reduce working time and extend service life of corrosion protection systems. Due to an increasing use of the “direct to metal” (DTM) system for corrosion protection of steel structures, this system was tested in the scope of this study and compared with the systems involving the use of primer coating. The tests were carried out on three types of corrosion protection systems.

A novel approach to hybrid hydraulic vehicles drive component sizing methodology based on the Willans Line method is proposed in this paper. The proposed method is used to develop a scalable mathematical model of hydraulic unit efficiency maps, thus helping the designer regarding an appropriate hydraulic unit choice when target unit data is difficult to obtain. The hydraulic unit efficiency model is also verified against catalogue data for different unit sizes, and the method is validated by means of detailed approximation error analysis. The proposed method can be particularly useful in optimal component sizing and parameterization studies of hydraulic drives in general, with possible applications to hybrid hydraulic vehicle power-trains.

Rocket motor propellant grain, cast or bonded into the motor chamber or solid coating, is exposed to various loads during its service life. Rocket propellant is a viscoelastic material, whose mechanical properties strongly depend on temperature and strain rate. Application of cyclic loads, primarily thermal, onto a rocket motor on the field stock, may cause an undesirable mechanical damage of the grain. Over time, after long storage, it may grow up and lead to the grain failure. One of the ways for evaluation of this phenomenon is to determine a cumulative damage law. In this example, this law has been evaluated for hydroxy terminated polybutadiene (HTPB) composite rocket propellant by exposing a number of specimens to different long term stress levels. Using this law, it is possible to calculate a probability of failure and time distribution of the structural reliability of the grain in order to determine the useful life. Besides, the analysis has shown that there is a possible correlation between tensile strength of the propellant and the cumulative damage law. This fact can be used instead of carrying a longterm experiment for the exact determination of the law.

Zagrebački Muzej za umjetnost i obrt pretprošle je 2017. godine u svoj zbirni fond prihvatio veliku donaciju baletnoga umjetnika Jelka Yureshe. Ovaj rad obrađuje najznačajniji dio (po vrsti artefakata) heterogene donacije – baletne kostime. Riječ je o u potpunosti stručno i znanstveno neobrađenoj građi te se ti kostimi sada prvi put dovode u svezu s baletima za koje su kreirani i opusima kostimografa koji su ih osmislili. Važan dio rada čini i (re)valorizacija značaja i muzealizacije čitave donacije, a uvodna poglavlja o životu donatora i o specifičnostima baletno-plesnih kostima čine pretekst interpretaciji i valorizaciji kostimā.

In 2006, the EU encouraged, facilitated and supervised the secession referendum of Montenegro. In 2014, the EU officials refused to facilitate a similar referendum in its member state Spain, and have so far denied any claims that Catalonia, when independent, would retain its membership of the EU. The paper argues that the EU policy towards secession referenda significantly affected the outcome of secessionist mobilization in these two cases. In spite of these sharp differences in the EU response, secessionist programs in both countries were ‘Europeanised’ in a similar way: in Montenegro, secession was aiming to facilitate the EU accession, and in Catalonia, to increase the benefits of retained EU membership. This paper explores the political and demographic context of the Europeanisation of secessionist programs. The majority of citizens in Catalonia and Montenegro do not identify as Catalan or Montenegrin only. The paper argues that the Europeanization of secessionist programs was, in part, an attempt to widen the appeal of secession to those who are not only Catalan or only Montenegrin.

This paper investigates potential uses of a novel direct driven electro-hydraulic systems for articulated forestry tractors (skidders), due to these systems having notably higher energy efficiencies compared to classical electro-hydraulic systems that are currently being used in skidders for steering, lifting the front and the rear plate, as well as for operating the double-drum winch. A detailed analysis of the skidder rear plate mechanism is carried out, and static force profiles of hydraulic cylinders are obtained for the rear plate based on mechanism dynamics and measurement data from the literature. Thus, obtained results have been used to emulate the real-life force profiles in laboratory experiments featuring both the classical and the proposed direct driven hydraulic systems for the purpose of comparative analysis of their energy and fuel efficiency. These results are subsequently used to estimate the skidder fuel consumption and possible fuel savings over the entire vehicle life span for the realistic vehicle utilisation scenario. The main result is that fuel consumption can be reduced up to five times in the case of direct driven hydraulic system, thus effectively resulting in return of investment period of about four years in the case of skidder being retrofitted with direct driven hydraulic system.

In order to meet the increasingly stricter emissions’ regulations, road vehicles require additional technologies aimed at the reduction of emissions from the internal combustion engine (ICE). A favorable solution from the standpoint of costs and simplicity of integration is a 48-V electrical architecture utilizing a low-voltage/high-power induction machine, which operates as the so-called engine belt starter generator (BSG) coupled via a timing belt with the ICE crankshaft within a P0 mild hybrid power train and used for starting up and boosting of the ICE power output, as well as for recuperating kinetic energy during vehicle deceleration. The aim of this work was to design a vibration damping system for the belt transmission within the so-called front end accessory drive (FEAD), which couples the BSG with the ICE crankshaft and to test the control system by means of simulations for realistic operating regimes of the P0 mild hybrid power train in order to show the functionality of the proposed approach in terms of mild hybrid vehicle performance improvement. Simulation results have pointed out effective attenuation of belt compliance-related vibrations using the proposed active damping control, with vibration magnitude reduced between three and five times compared to the default case during engine start-up phase. They have indicated the realistic belt slippage effects during engine start-up phase and have illustrated the effectiveness of the FEAD torque boosting capability with 30% gain in acceleration during vehicle launch.

This paper aims to determine cost optimality between heating, ventilation and air conditioning (HVAC) systems operating with air to water heat pumps (AWHP) and water to water heat pumps (WWHP). The analysis is performed for a certain number of heat pump units with fixed and variable capacity made by four manufacturers available on European market. Simulations are performed in Trnsys software. The results show that heat pump partial load efficiency should not be neglected in analysis of application while the difference in energy consumption and costs can be up to 17%. The requirement for performing analysis on a wider range of units is indicated, especially when heat pump systems with different sources are considered. HVAC system with AWHP units with capacity control is a cost optimal solution for case study nursery building operating on the Croatian coast. The application of the photovoltaic (PV) array sized to cover nonrenewable part of electricity consumed in HVAC system has a return period of 12 years. It is determined that seasonal efficiency indicators from relevant European database do not support unit operation.

Dan kada sam čula da, onaj da o kojemu sam tako malena i jadna bila toliko sanjala, konačno je stigao jedne subote. Mjesecima, odnosno svaki put kada bi me moj otac odveo u park Bijela voda, molila bih ga da mi kupi balon. Međutim, on bi me svakoga puta odbio s istim, meni nerazumljivim riječima: „Premala si!” Nisam inzistirala poput ostale djece, koja su plakala, lamatala nogama i vrištala prisiljavajući tako roditelje da im ispune želje ili da ih ušutkaju snažnim pritiskom svojih dlanova. Ja bih se samo rastužila, a nastojala sam se oraspoložiti šećernom vatom koju bi mi otac kupio. Čak i kada bih se zabavljala na toboganu, na vrtuljku ili na klackalici, osjećala sam se kao koncem vezana za taj san o balonu u budućnosti. A onda, jedne subote, dok smo ulazili u park, ja odjevena u bijelu suknju i već spremna čuti još jedno ne, vidjela sam svojega oca kako se približava prodavaču balona i govori: „Narasla si, kćeri, smiješ izabrati jedan!” To je bio toliko velik trenutak da sam se cijela prestrašila, da mi se raširio osmijeh preko lica i da mi je bila oduzeta moć govora te sam samo prstom pokazala na jedan balon. Hodala sam parkom, ponosna, sa svojim ocem, koji me držao za ruku; u drugoj sam nosila, poput kakve princeze, najvrednije blago svojega kraljevstva. Vjetar je njihao balon naprijed-nazad, nježno ga je pomicao s jedne strane na drugu, a ja sam poput njega bila, gotovo do razine pucanja, napuhnuta od tolike sreće. Malo sam se poigrala u pješčaniku, na brzinu sam pojela kokice, samo sam htjela defilirati s tim snom jednom niti privezanim za moj prst. Međutim, kada smo izlazili, omeo me psić koji mi je prišao kako bi me polizao po nogama te sam, zbog nepažnje, mazeći ga, slučajno ispustila balon, a on se sporo uspeo prema nebu. Stajala sam i gledala ga nepomična, u bijeloj suknji i razočaranju, venući sa svakim metrom kojim se zauvijek udaljavao od mene. Tada sam shvatila zašto mi je otac toliko puta odbio kupiti balon: da se ne bih prerano suočila sa svojim prvim gubitkom. Jer poslije ne bi bilo drugoga izlaza – i nema ga! – osim prihvaćanja svih ostalih gubitaka, koji će nemilosrdno pristizati u slijedu, jedan za drugim. Dan kada sam čula da bio je i dan kada sam čula najveći ne u svojemu životu.

The formation of an educated and a successful personality depends on a number of pedagogical, sociological and social factors. In the process of socialization and education, both contemporary school system and family share responsibility and make an important role in the success, not only of individuals, but of society as a whole. The influence of the family environment on achievement can be seen from different aspects. The aim of the research was to examine the connection between achievement of deaf and hard-of-hearing students and factors of the family environment seen through their socioeconomic status. The survey sample comprised 59 parents of deaf and hard-of-hearing children attending the school for deaf and hard-of-hearing students in the territory of the Republic of Serbia. In the process of relevant literature research and determining the theoretical facts relevant for the research problem, the method of theoretical analysis and synthesis was used. In relation to research techniques, survey and content analysis were used. Family questionnaire was used to analyze the link between the socioeconomic status of families and achievement of deaf and hard-of-hearing students. The results have shown that there was no correlation between the socioeconomic status of the families and the school achievements of deaf and hard-of-hearing students.

Identification of a dynamical model and its parameters is one of the fundamental problems in the field of robotics and system dynamics modelling. For the general situation of an object motion with six degrees of freedom (6-DOF), such as in the case of the Unmanned Aerial Vehicle (UAV), the key physical parameters are vehicle mass and moment of inertia. Even though UAV mass and its geometry/topology are easily obtainable, it is difficult to identify the inertia tensor considering that it is not measurable by static tests. This article presents a simple and effective method for on-line estimation of a rigid-body inertia based on a two-wire pendulum and an on-board integrated sensor system. Herein, the test subject (i.e. UAV) is suspended by two thin parallel wires in such a way to form a bifilar torsional pendulum about the vertical axis. Using on-board sensors from the UAV flight controller (FC) unit, the pendulum oscillations are recorded and processed in order to obtain trend-free and noise-free signals used in the final inertia estimation phase. The proposed identification algorithm is verified experimentally for two typical cases of a suspended objects related to the UAV control box and a full UAV configuration.

Existing design support tools and methods struggle to deal with numerous data management situations that arise in medium and large-scale design projects. Authors analyse and compare the suitability and efficiency of several methods for managing and visualization of relationships between engineering objects and propose guidelines for building a framework/interface for consolidated usage of those methods in industrial practice. The proposed matrix-based consolidation methodology builds on findings gathered from two monitored design projects as well as previous research in areas of traceability and visualization. For engineering objects (data sets) that belong to one or two domains which are not hierarchically structured it is argued that a simple matrix interface is sufficient to record the relations. Furthermore, if the engineering objects are hierarchically structured the browser interface is suggested. In the most complex situation, where objects belong to multiple different domains the use of diagrams and digital white boards is suggested.

Defining and properly measuring financial literacy of students is a prerequisite for proposing education policy solutions. The main objective of this paper is to present a procedure of financial literacy assessment. The measure is based on the results of the survey conducted on a suitable sample of students at the University of Zagreb. It is developed using confirmatory factor analysis, which involves testing the validity of a measurement model. This model consists of four manifest variables: Knowledge, Attitudes, Behavior and Practical Knowledge, which are used to estimate a composite measure of financial literacy. The results of factor analysis were later used for obtaining the corresponding weights of indicators of financial literacy. The estimated measure indicates great heterogeneity in the level of financial literacy among students from different constituent units of the University of Zagreb.

This paper presents the results of research into the role which dimensions of national culture have in shaping tourist behaviour and preferences with the aim to establish quality tourist service and the desired reputation, especially concerning foreign tourists who are characterized by their own cultural features and values. The purpose of this paper is to discover the particularities of the interrelatedness of the dimensions and determine a recommended way of creating a quality tourist service through analysing each particular dimension of national culture and its role in the context of tourist behaviour and preferences. The methods applied in the paper include identification and definition of national culture, defining and determining particularities of national culture dimensions as well as observation of the role of national culture dimensions in shaping tourist behaviour and preferences, which may have relevant implications on creation and management of proper reputation of a tourism product. One of the conclusions of the paper is that dimensions of national culture have an important role in shaping tourist expectations, behaviour and preferences.