The paper presents results of detailed geological research of quartzite in the wider area of Smrčevice, southeastern of Gornji Vakuf-Uskoplje. Based on the defined boundaries of surface distribution and research results, geological reserves of about 12 million tons have been determined in the wider area of Smrcevica. The quartzite reserves that have been so far determined in this area are at a low level of geological research. The paper contains an overview of the geological characteristics of the area, qualitative and quantitative characteristics of quartzite, and the mineral raw material potential of quartzite in the Smrčevice area according to the PERC standard. The results of the conducted research indicate that the general geological and technical-exploitation factors are relatively favorable and indicate a possible profitable exploitation of the deposit. Taking into account the significant raw material potential, and the possibility of expanding the existing raw material base, this area has special importance for the perspective development of quartzite exploitation and its use in the production of ferrosilicon and silico-metals.

This paper discusses the design and analysis of a modified test bench for high-voltage direct-current (HVDC) circuit breakers which consists of a power converter based on multiple cascaded H-bridge cells, a small-sized inductor, and an auxiliary capacitor bank. It is capable of producing output voltages up to several hundred kilovolts depending on the auxiliary capacitor bank while allowing for high current controllability via the power converter which is driven by phase-shifted pulse-width-modulated (PSPWM) signals. Consequently, the test bench can generate a wide range of controllable current waveforms and high current gradients, within hardware limitations, to simulate a wide range of fault conditions. The flexibility of the proposed design is complemented by higher reliability and longer lifetime. The concept of the test bench was verified by experiments using a down-scaled model based on nine cascaded H-bridge cells with an equivalent switching frequency of 92.5 kHz.

The focus of this text is twofold. The first task is to reconsider the mode of interpretation of various small (4 to 10 cm) objects (axes, chisels, finger-rings, pendants), made of green minerals – jadeite and/or nephrite. These objects are registered on 15 sites in the territory of present-day Serbia, dated into the Neolithic period (6200/6000–4600/4500 cal BC). The second task is to lay out a short history of the green colour. As stated by Michel Pastoureau (Pasturo 2015), the production of a green pigment was almost impossible in the past, especially in praehistory. The first recorded attempts are linked to Ancient Egypt, and the oldest successful production of the green pigment is dated to Ancient Rome. Therefore, the text examines the symbolic role of these small green objects during the Neolithic. The beds of green minerals jadeite and nephrite are not recorded in the territory of Serbia. Jadeite may be found south of Skopje (Mt. Solunska glava), in the Cyclades in Greece, as well as in the Piedmont Alps. Nephrite is registered in the mountain Ogražden (SW Bulgaria), in Poland, Sweden, and Italy. The absence of mineral layers in the region surely suggests the existence of long-distance exchange. This raises the issue of the role and symbolic function of these objects – what was their appeal for the past communities and what was the role of their colour in their manufacture? In archaeology, the studies in symbolics of various colours are rare. Authors have mainly focused upon the origin of the colour and the dating of the objects, but the role of the colour itself as the criterion in choosing various raw materials has largely been neglected. Notable is the exception of the thematic collection “Colouring the Past: The Significance of Colour in Archaeological Research” (2002), where attempts have been made to explain the symbolic importance of various colours in the past. However, the colour green is not mentioned. This paper does not aim to offer final solutions, but to investigate the usage and importance of the colour green on the grounds of the usage of the objects themselves.

Dimenhydrinate (DMH) is used for the prevention and treatment of nausea, vomiting, dizziness and vertigo associated with motion sickness in a dose of 50 mg 1. It’s made of two drugs in a form of salt, diphenhydramine and 8-chlorotheophylline which synergically decrease motion caused neural excitation 2. DMH is classified as a slightly soluble drug and it belongs to class II of BCS classification as a drug with low solubility and high permeability 3. Cyclodextrins (CDs) are cyclic oligosaccharides formed by α-1,4-linked glucose units with a hydrophilic outer surface and a lipophilic central cavity. Formation of inclusion complex by incorporating a drug in the central CD cavity provides improvement of physicochemical properties without molecular modifications. Solubility and dissolution rate of poorly water-soluble drugs can be increased 4. Aqueous solubility of natural CDs is limited due to their tendency to form H-bonded associations. However, due to multiple reactive hydroxyl groups, their functionality can be greatly increased by chemical modification 5. CDs’ substituted derivates can overcome poor solubility issues and enhance bioavailability. Hydroxypropylβ-CD (HP-β-CD) has good inclusion ability, high water solubility and it’s safe for intravenous and oral administration 6. Stability constant (Ks) and complexation efficacy (CE) are important for assessing the binding characteristics of the drug and CD. They can be determined by the phase solubility studies where the change of the drug solubility is corresponding to the concentration of CD 7. Linear (AL) type of the curve implies that one molecule of the drug forms inclusion complex with one molecule of the CD. Apparent stability constant K1:1 can be calculated from the following equation:

The development process of the knowledge-based engineering (KBE) system for the structural size optimization of external fixation device is presented in this paper. The system is based on algorithms for generative modeling, finite element model (FEM) analysis, and size optimization. All these algorithms are integrated into the CAD/CAM/CAE system CATIA. The initial CAD/FEM model of external fixation device is verified using experimental verification on the real design. Experimental testing is done for axial pressure. Axial stress and displacements are measured using tensometric analysis equipment. The proximal bone segment displacements were monitored by a displacement transducer, while the loading was controlled by a force transducer. Iterative hybrid optimization algorithm is developed by integration of global algorithm, based on the simulated annealing (SA) method and a local algorithm based on the conjugate gradient (CG) method. The cost function of size optimization is the minimization of the design volume. Constrains are given in a form of clinical interfragmentary displacement constrains, at the point of fracture and maximum allowed stresses for the material of the external fixation device. Optimization variables are chosen as design parameters of the external fixation device. The optimized model of external fixation device has smaller mass, better stress distribution, and smaller interfragmentary displacement, in correlation with the initial model.