ABSTRACT In the bauxite-bearing area of Jajce (Bosnia & Herzegovina), exploitation of karst bauxite has occurred for more than 40 years, during which time extensive geological and mining research was also conducted. Here, the geological map of the Jajce bauxite bearing-area (Bosnia & Herzegovina) at a scale of 1:25.000 is presented, accompanied by a geological column and regional geological cross-sections. The map shows the main stratigraphic and tectonic features and positions of the bauxite deposits of the area. This research area covers 343 km2, divided into two structural units with four bauxite districts, Liskovica, Bešpelj, Crvene Stijene and Poljane. The Liskovica-Bešpelj structural unit is tectonically very complex, characterized by W-E trending structures in subvertical, vertical and overturned positions. The Crvene Stijene-Poljane structural unit is characterized by gentle folds and normal faults. The geological map summarizes all the available data and represents the necessary basis for further geological and mining research of the area.
A significant challenge in the rational design of organic thermoelectric materials is to realize simultaneously high electrical conductivity and high induced-voltage in response to a thermal gradient, which is represented by the Seebeck coefficient. Conventional wisdom posits that the polymer alone dictates thermoelectric efficiency. Herein, we show that doping — in particular, clustering of dopants within conjugated polymer films — has a profound and predictable influence on their thermoelectric properties. We correlate Seebeck coefficient and electrical conductivity of iodine-doped poly(3-hexylthiophene) and poly[2,5-bis(2-octyldodecyl)pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione-3,6-diyl)-alt-(2,2′;5′,2′′;5′′,2′′′-quaterthiophen-5,5′′′-diyl)] films with Kelvin probe force microscopy to highlight the role of the spatial distribution of dopants in determining overall charge transport. We fit the experimental data to a phonon-assisted hopping model and found that the distribution of dopants alters the distribution of the density of states and the Kang–Snyder transport parameter. These results highlight the importance of controlling dopant distribution within conjugated polymer films for thermoelectric and other electronic applications. Designing organic thermoelectric materials with high electrical conductivity and Seebeck coefficient is challenging due to the direct relationship between these two properties. Here, the authors explore the role of dopant spatial distribution on thermoelectric performance in conjugated polymers.
This paper presents an off-body channel model for polarized communications with dynamic users. The model is based on Geometrical Optics and Uniform Theory of Diffraction and accounts for free space propagation, reflections, and diffractions. It allows for arbitrary antennas’ polarizations and gain patterns and supports a number of on-body antenna placements. In order to take the influence of users’ motion into account, a mobility model for wearable antennas on dynamic users is used. Signal depolarization mechanisms are identified, and simulations are performed to analyze the influence of user dynamics on the channel. The results show that significant polarization mismatch losses occur due to wearable antenna rotations, resulting in received power variations up to 37.5 dB for the line-of-sight component and 41.4 dB for the scattered one. The importance of taking signal polarization into account is demonstrated by comparing the simulation results between polarized and nonpolarized channel models in a free space propagation scenario, where a difference up to 53 dB in between the two is observed.
This paper describes a rational approach to improve the existing guidelines for road design in the regions of Slovenia, Croatia, Bosnia and Herzegovina, and Serbia in order to determine the carriageway crossfall in curves. In these guidelines there are certain shortcomings in determination of crosfall in comparison to some other European countries guidelines. During the last decades, worldwide and in Europe specifically, significant studies have been conducted on the issue of the operating speed and its implementation into the design process. Most European countries have been implementing this concept. The new German guidelines went a step further and introduced a new concept of a self-explaining class road. Using the results of research carried out in Croatia, this work focuses only on a determination of the carriageway crossfall based on operating speed, separately observing new and existing roads. Whereas the new road segments require implementing the principle of a consistent route, an existing road network can be safely improved only by introducing the criteria of the determination of crossfall in curves based on the operating speed.
Ensuring access to reliable and sustainable power supply is becoming more and more challenging due to a combination of factors such as more frequent power grid outages caused by extreme weather events, the large-scale introduction of renewable energy resources that increases the complexity of the power system, but also aging infrastructure, supply and demand imbalance and power theft in some areas. Combined, all these factors can cause outages and together they can make electricity supply unreliable. The implications of this are many, ranging from minor inconveniences to major failures of critical infrastructures. A potential solution to ensure power supply during outages is to use local generation in the form of renewable resources to supply energy. This paper proposes a community-based mechanism that demonstrates that when community members can determine for themselves how excess energy generation is distributed, the power supply of specific members can be ensured. Self-determination is achieved by prioritizing and differentiating between community members as well as automatically and continuously redistributing energy, thereby adapting to sudden changes in supply and demand. Simulation results show that the proposed mechanism can be used to empower local communities to decide for themselves how local resources are distributed during events such as outages, ensuring prolonged power supply for differentiated members of affected communities. Harnessing the potential of renewable resources and smart technologies for intelligent coordination through empowerment of consumers to become pro-active participants is a promising solution for the future power systems.
This paper analyses information literacy competencies of students at the Department of Comparative Literature and Library Science, Faculty of Philosophy, University of Sarajevo that offers bachelor's degree and master's degree in library science. Survey on information literacy competencies of library science students at the Department was realized by the online questionnaire for self-assessment that was developed on the basis of Permutation Model Components with the purpose to obtain insight in student’s perception of their information literacy competencies, to detect to what degree students improve their information literacy competencies and confidence during studies and what possible difficulties they face in this process. This is particularly important considering that there is no separate information literacy course adopted in Departments curricula but the information literacy related content is offered and taught in different courses. Analysis expectedly reveals that in general students feel confident in their information literacy competencies, that their information literacy competencies progressively improve during their studies, but also that students consider that the introduction of a stand-alone information literacy course would greatly contribute to the simpler and faster improvement of their information literacy competencies.
This paper presents a numerical analysis of a reinforced concrete beam in which the concrete and reinforcement are above the yield strength of the material. Further, the procedure for determining the relationship between the cross-sectional forces and the deformations of the layered cross-section of a rod is described. For a short rod with reduced stiffness of the EI and EA cross-sections, a stiffness matrix with variable members is formed. The applicability of the proposed analysis method for the material nonlinearity in a beam calculation is demonstrated through a numerical example. The aim of the present paper is to show the flow of plastification and the load deformation of the system nodes. Finally, the results of the manual deformation calculation system are compared with the results from SCIA software.
Radno mjesto je okruženje unutar kojeg čovjek provede najveći dio aktivnog dijela svojega života. Događanja unutar radnog okruženja, tretman radnika na radnom mjestu, kao i atmosfera koja se stvara unutar radne organizacije umnogome utječu, ne samo na raspoloženje, produktivnost i učinkovitost radnika, već vrlo često i na njegovo zdravlje. Diskriminacija na radnom mjestu je jedan od negativnih, ponižavajućih i degradirajućih oblika tretmana radnika koji, zbog intenziteta posljedica koje proizvodi za pojedinca i njegovo, prije svega, psihičko zdravlje, njegovu obitelj, radnu organizaciju i društvo u cjelini, zaslužuje posebnu pozornost u razmatranju uzroka i posljedica ove negativne pojave. Pri tome je posebno značajno punu pozornost posvetiti iznalaženju adekvatnih načina prevencije diskriminacije kako do njezinih negativnih posljedica uopće ne bi niti došlo ili kako bi se one smanjile na najmanju moguću mjeru. U primjeni različitih modela prevencije diskriminacije, posebno djelotvornima su se pokazali modeli koji uvažavaju postojanje različitosti među ljudima, te ih ne smatraju preprekama, već upravo korisnim resursima za razvoj radne organizacije, kao i u stvaranju ugodne radne atmosfere i povećanju kvalitete i produktivnosti rada. Stoga je ovaj rad posvećen modelu stvaranja kulture tolerancije, primjeni tzv. pozitivnih mjera, te diversity managementu, kao mogućnostima koje stoje na raspolaganju kao modeli prevladavanja problema različitosti među ljudima u radnim odnosima, te ulozi antidiskriminacijskog zakonodavstva na tom polju.
Resistive pressure sensors has become popular and used in different applications. The usage of the pressure sensors in designing wearable solutions requests flexible and light materials. However, these materials are exhibiting challenging behavior in respect to precision, sensitivity and repeatability of measurement. In this paper we present a set of experiments demonstrating typical problems, and also we discuss the causes and possible remedies. The experiments were conducted with pressure sensors implemented using the VelostatTM material and Arduino platform for acquisition of the measurements.
Over the past decade technological development has lead to systems being connected to public networks in many critical domains. In such systems bringing safety and security work has become even more important, as a connected safety-critical system is not safe if it is not secure. Given this, the main goal of this study is to investigate the current status of safety and security co-analysis in system engineering by conducting a Systematic Literature Review. In this work we have focused on the early system development stages and identified 33 relevant publications categorised as: combined safety and security approaches that consider the mutual influence of safety and security; safety informed security approaches that consider influence of safety on security; and, security informed safety approaches that consider influence of security on safety. The results showed that a number of identified approaches are driven by needs in fast developing application areas, e.g., automotive, while works focusing on combined analysis are mostly application area independent. Overall, the study shows that safety and security co-analysis is still a developing domain, which requires solutions that rely on two separate disciplines, namely safety and security engineering.
Latest technological trends lead toward systems connected to public networks even in critical domains. Bringing together safety and security work is becoming imperative, as a connected safety-critical system is not safe if it is not secure. The main objective of this study is to investigate the current status of safety and security co-analysis in system engineering by conducting a systematic literature review. The steps of the review are the following: the research questions identification; agreement upon a search string; applying the search string to chosen databases; a selection criterion formulation for the relevant publications filtering; selected papers categorization and analysis. We focused on the early system development stages and identified 33 relevant publications categorized as follows: combined safety and security approaches that consider the mutual influence of safety and security; safety-informed security approaches that consider influence of safety on security; and security-informed safety approaches that consider influence of security on safety. The results showed that a number of identified approaches are driven by needs in fast developing application areas, e.g., automotive, while works focusing on combined analysis are mostly application area independent. Overall, the study shows that safety and security co-analysis is still a developing domain.
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