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For the first time, development of freight forwarding, as an economic activity in Serbia, is analysed in this paper. At the beginning, a brief literature review on the origin and evolution of freight forwarding is given, as well as the research motivation and goal. Currently, there is any study that systematically deals with the historical development of the freight forwarding in Serbia. The development of freight forwarding in the period before the Second World War is almost entirely unknown. The main goal of presented research is to highlight a long tradition of the freight forwarding in Serbia and significance of its exploring. An analysis of archival material available in the archives and libraries of the Republic of Serbia revealed that the first freight forwarding firms, engaged in some of the basic modern freight forwarding operations (custom brokerage, transport organization, storage of customs goods, etc.), were mentioned at the end of the XVIII century. Socio-political, economic, and other historical circumstances directly affected the characteristics of freight forwarding businesses and companies. The paper briefly describes the development of freight forwarding over the time through a description of the basic characteristics of freight forwarding companies (size, types of business, geographical distribution, and others) within the distinct periods from the XVIII to the XXI century.

Freight forwarding is a complex economic activity that requires multidisciplinary and interdisciplinary knowledge. The paper explores teaching freight forwarding as a scientific discipline at higher education institutions in the Republic of Serbia. The aim of this research is to show the connection between the development of freight forwarding courses at higher education institutions with the development of profession, technique, technology, necessary knowledge and skills. The accredited academic bachelor's, master's and PhD programs, as well as applied studies programmes are included in the analysis. The results of the research show that freight forwarding is mainly studied under traffic and transportation engineering programmes. However, certain areas of vital importance for freight forwarding are studied, from different aspects, at several different faculties and under various accredited programs. Two basic conclusions emerge from the obtained results. First, there is a raising need for the knowledge of new techniques and technologies in order to manage the shipment, delivery and transit of goods in a qualitative manner. This is the reason why the contemporary studying of freight forwarding is closely connected with traffic and transportation engineering and, in a narrower sense, logistics. Secondly, multidisciplinarity and complexity are the main characteristics of the necessary knowledge and skills to perform freight forwarding activities. Thus, certain freight forwarding topics and important issues are studied at various faculties and different scientific fields.

Russian made FPM-GMO-1.6 flotation machines were previously installed for primary stage flotation concentration of lead and zinc minerals in Lece flotation plant. For cleaning stage FMR-10 flotation machines were in use. Beside low technological characteristic, hard maintenance and worn out are characteristic of this machines. In order to modernize the production and eliminate the above shortcomings primarily in the process of lead minerals flotation, in 2020, the old flotation cells were replaced with new ones. Currently, 8 new RCS-5 cells for coarse and scavengel flotation of lead minerals and 4 RCS-3 cells for cleaning of coarse lead mineral concentrate are working on the lead flotation line in Lece flotation. These cells were produced by Metso Minerals from Finland. Flotation cells, which are installed, have modern technical - technological characteristics, with all the accompanying equipment for automatic control of pulp levels and air consumption. This paper presents comparative characteristics of old and new flotation cells, their appearance and characteristics and technological results achieved in flotation with old and new cells.

Alumina (Al2O3) nano fibers are prepared from an aqueous solution of aluminum hydroxy chloride/poly (vinyl alcohol) (PVA)/water using the electrospinning technique. The weight ratio of aluminum hydroxy chloride/PVA was 5: 1. After calcification of fibers at 1100 ° C, continuous aluminum oxide fibers were obtained from 200 to 800 nm. The fiber morphology is characterized by a scanning electron microscope (SEM). Image analysis software (Image Pro Plus) was used to measure the diameter of the obtained aluminum oxide (Al2O3) fibers. The aim of this paper is to examine the mechanical properties of the hybrid composite, consisting of a polymer matrix (ethylene and vinyl acetate copolymer (EVA)), ultrahigh molecular weight polyethylene fibers (UHMWPE) and Al2O3 fibers obtained by electrospinning. Al2O3 fibers were added in an amount of 1 wt. % as shown by the improvement of the mechanical properties of the matrix and the hybrid composite.

The paper presents a general model for the strategic management of postal infrastructure and resources, focused on development of warehousing service. The model was developed according to the characteristics of the public enterprise 'Pošte Srbije'. A set of indicators is developed for the purpose of analysis of external and internal environment of PE 'Post Serbia'. For positioning the focal postal enterprise among other, selected European posts, the benchmarking method is used, whereby indicators are determined by using eigenvalues and eigenvectors. Analysis of internal environment additionally includes survey and Delphi method to obtain the values of coefficients in the model. With small modifications, the model could be applicable to all postal operators and logistics companies which consider to develop warehouse service in logistics market.

A possibility of using inorganic fullerene-like tungsten disulfide, IF-WS2, nanoparticles as a filler in poly (vinyl butyral), PVB, for improving its thermal and rheological properties is examined. PVB is a thermoplastic polymer with excellent properties, widely used: in ballistic protection, for protection of safety glass, in metal primers and coatings, temporary binders. Two different molecular weights of PVB were previously examined in this research: Mowital B60H and B75H. Both grades of PVB were dissolved in different solvents: ethanol and 2-propanol. Thin films were prepared by solvent casting technique. The glass transition temperature (Tg) of the tested samples was determined using differential scanning calorimetry (DSC), at three different heating rates (5°C/min, 10°C/min and 20°C/min). After choosing a solvent and PVB grade, IF-WS2 nanoparticles were added to PVB solutions and dispersed by ultrasonic irradiation. Compatibility, i.e. interaction of IF-WS2 with the dissolved PVB was examined by microcalorimetry method. The nanoparticles dispersion and deagglomeration in matrix of PVB was analyzed by scanning electron microscope (SEM). The effect of IF-WS2 on rheological properties of the chosen samples has been examined using Dynamic Mechanical Thermal Analysis (DMTA), observing storage modulus, loss modulus and the loss factor as functions of temperature for the tested composites.

In this paper, the impact of wood fiber surface modification on mechanical properties of poly-(methyl methacrylate)(PMMA)-wood composite was examined. FTIR analysis has shown that the wood fiber surface modification was accomplished and that the matrix-fiber bond was established. The SEM image of the breakage surface has affirmed the improved adhesion between the fibers and the polymer in the specimen with modified wood fibers. The bond improvement between the wood fibers and the matrix results in increased hardness and a better distribution of strain within the composite. High speed impact testing results have shown that the specimen with the bonding agent can increase the absorbed energy six times when compared to the pure PMMA specimen.

The physical and mechanical properties of the six samples of polyurethane/p-aramid multiaxial fabric forms (Kolon fabrics) were analyzed by high speed impact tester. The samples were impregnated with 10 wt.% poly (vinyl butyral) (PVB)/ethanol solution and modified with γ-aminopropyltriethoxysilane (AMEO silane)/ethanol solution. Unmodified silica (SiO2) nanoparticles, tungsten disulfide (WS2) nanoparticles and multiwalled carbon nanotubes (MWCNT) were used as reinforcement for multiaxial Kolon fabrics. The SiO2/PVB mass fraction was 10 wt.%, while the WS2/PVB and MWCNT/PVB mass fractions were the same - 1 wt.%. The results revealed the increase of the maximal impact force and the total energy absorbed for all the samples compared to the unmodified Kolon fabric sample and the application possibilities of these materials for the antiballistic protection.

The electronic structures of CdS quantum dot (QD) with dielectric mismatch are calculated. Poisson equation is solved analitically in case of point charge placed inside semiconductor sphere embeded in dielectric matrix in case of different values of the dielectric permittivity of QD and matrix. The validity of the effective mass approximation for the conduction band is assumed. Schrödinger equation for one electron is solved analitically. On the basis of the Poisson equation solution self potential is examined and used as perturbation to calculate the self-polarization effect.

Optical and structural properties of materials can be characterized by spectroscopic ellipsometry which represents an experimental technique that measures polarized light reflected from a material surface. Since the most complicated part of this method is data analysis and modeling, we present the calculation of the ellipsometric parameters for bi-isotropic materials. We consider the ellipsometric model for these materials which require not just permittivity like in conventional model, but also magnetic permeability and magneto electric coupling.

In this paper the process of electrospinning of PMMA nanofibers was investigated. The influence of process parameters (type of solvent, solution concentration, flow rate, distance of needle and collector) on the nanofibers diameter uniformity and porosity was investigated. Characterization of obtained samples was performed by FTIR, DSC, SEM and Image-pro picture analisys. The optimal process parameters were defined.

This paper investigates the role of performative models within the context of architectural design. Understanding the performances of the built environment can be postulated in rather different manners. It is commonly expected that the built environment complies with the diverse and changing requirements of its users. It is equally required that buildings are economically constructed, easily maintained, energy efficient, safe and aesthetically pleasing. Yet, such expectations are complex and consist of a great number of intertwined effects that are not easy to synchronize during architectural design process. Although they can be precisely evaluated and quantitatively expressed, the values specifying the performances, such as temperature, humidity and intensity of light or sound, in traditionally established course of architectural design are usually only considered throughout the post-rationalization or correction of the architectural design. The research presented in this paper explores design mechanisms, for direct and formative incorporation of feedback information into the very conception of architectural form.