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The text outlines and analyses the relations between India and Serbia from the formal establishment of diplomatic relations in 1948 till the present. The author gives special attention to the political and economic relations between the two countries. In the context of political relations, the author discusses the meetings that took place at the highest level as well as the significance of the Non-Aligned movement. With regard to economic relations, the paper points to the importance of bilateral cooperation that has developed since the establishment of diplomatic relations and has intensified in the past few years, with concrete results being achieved.

The assessment of the suitability of the granulometric composition of the crushed stone aggregates (CSA) for an unbound base and subbase layers of pavement, in the Republic of Serbia is done based on the defined gradation bands, uniformity degree (Cu), coefficient of curvature (Cz), percentage of fines and percentage of particles passing a 0.02 mm sieve. On the other hand, standards which define the quality requirements of aggregates and unbound mixtures for road construction SRPS EN 13242 and SRPS EN 13285 introduce a significantly different approach to the assessment of the granulometric composition suitability. Categories are defined. Each category includes a particular boundary band, tolerances on sieves, differences in values passing each sieve. The categories are defined depending on the field of the application. For seven CSA 0/31.5 mm used for the construction of Corridor XI, a comparative analysis of the granulometric composition suitability was performed according to the requirements of the existing Technical Specifications (TS) of PE "Roads of Serbia" (PERS) and the specified SRPS EN standards. The analysed curves satisfy those technical requirements, but vary in categories from the most severe mixtures of the normal granulometric composition of the GA category, to the open mixtures of the GP category. It was concluded that the principle based on the defining allowed tolerances on the sieves and between the sieves, is more suitable for field control of of the granulometric composition and the good granularity of the aggregates. Technical Specifications should be modified to this approach.

A steam turbine trip is followed by a prompt closure of stop valves in front of the turbine and consequently to a pressure rise in the main steam pipeline. This steam hammer transient leads to the generation of intensive fluid dynamic forces that act along the pipeline axis and induce additional dynamic loads on the main steam pipeline. It is a common practice to assume a simultaneous closure of all stop valves in the safety analysis of the main steam pipeline. In the present paper computer simulations and analyses of the fluid dynamic forces are performed for several scenarios that take into account the possibility of delayed closure of the stop valve in front of the turbine. The influence of the failure of the steam by-pass line opening is considered too. The results show that the delay of the stop valve closure increases the maximum intensity of fluid dynamic force in the pipeline segment in front of the stop valve and decreases the intensity of fluid dynamic forces in segments along the pipeline. The failure of the by-pass line to open leads to prolonged steam pressure and fluid dynamic forces oscillation in pipeline segments. The simulations were performed with the in-house computer code based on the method of characteristics for the solving of the hyperbolic system of PDE that represent the mass, momentum and energy balance equations of the 1-D, compressible and transient fluid-flow. The obtained results are a support to safety analyses of thermal power plants under transient conditions. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR-34028]

Traffic congestion is defined as mutual obstruction of traffic by vehicles due to the existing relation between the speed of vehicles and the flow in conditions of exceeding the capacity of the infrastructure. The paper presents an analysis of local experts survey on the role of non-motorized and motorized ways of travel to reduce congestion, as well as a comparison with the assessments given by foreign experts. The performance and the impact of different modes of transport (motorized and non-motorized) on congestion in urban conditions were assessed. The impact of the mode of transport on congestion was assessed using measures that are usually implemented in cities. Possibilities for improving multimodal mobility with an emphasis on walking and cycling have also been identified, as the most perspective ways due to the relatively low costs of implementation and the potential to affect the modal distribution.

The “corrected accelerated service life test for hydrogen evolution reaction” (CASLT-HER), designed for application of certain electrode materials as cathodes in the cell for alkaline water electrolysis in 30 % KOH at 80 °C, was performed at electrodeposited NiSn alloy and Ni 40 mesh electrodes. The Ni 40 mesh was slightly etched, while the NiSn alloy coating was electrodeposited from the bath containing pyrophosphate, glycine, SnCl2 and NiCl2 onto Ni 40 mesh to the thickness of approximately 40 μm. It is shown that the NiSn cathode possess from maximum 0.77 V to minimum 0.30 V better overpotential than the Ni 40 mesh electrode during the 5 years of their exploitation at the conditions of industrial alkaline water electrolysis. It is also shown that both electrodes should be held at j = –0.3 A cm-2 for at least 5 h in order to establish stable overpotential response. The limiting overpotential values for applying cyclic voltammetry (CVs, to mimic “polarity inversion”) should be determined in a separate experiment before the CASLT-HER and should be adjusted during the application of CVs. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 172054]

This paper reviews the current status of boiling heat transfer modelling, discusses the need for its improvement due to unresolved intriguing experimental findings and emergence of novel technical applications and outlines the directions for an advanced modelling approach. The state-of-the-art of computational boiling heat transfer studies is given for: macro-scale boiling models applied in two-fluid liquid-vapour interpenetrating media approach, micro-, meso-scale boiling computations by interface capturing methods, and nano-scale boiling simulations by molecular dynamics tools. Advantages, limitations and shortcomings of each approach, which originate from its grounding formulations, are discussed and illustrated on results obtained by the boiling model developed in our research group. Based on these issues, we stress the importance of adaptation of a multi-scale approach for development of an advanced boiling predictive methodology. A general road-map is outlined for achieving this challenging goal, which should include: improvement of existing methods for computation of boiling on different scales and development of conceptually new algorithms for linking of individual scale methods. As dramatically different time steps of integration for different boiling scales hinder the application of full multi-scale methodology on boiling problems of practical significance, we emphasise the importance of development of another algorithm for the determination of sub-domains within a macro-scale boiling region, which are relevant for conductance of small-scale simulations.

In this work, the dissolution behavior of a polyphosphate glass, with the composition 45P2O5·3SiO2·25K2O·15CaO·10MgO·ZnO·MnO (mol %), in simulated body fluid (SBF) at a temperature of 37 °C for different times was studied. Two powder sizes of the glass (granulation: 0.1–0.3 and 0.3–0.65 mm) and the bulk glass were investigated. The dissolution experiments were conducted under stationary conditions. Changes in the normalized mass release, normalized concentration of ions, pH values, and surface morphology were determined as a function of the dissolution time. The initial rates of glass powder dissolution and leaching of ions, as well as the diffusion coefficient of cations and the releasing rate of ions, during the hydrolysis process of glass were determined. It was shown that the investigated phosphate glass dissolves in SBF incongruently, with neither precipitation nor the formation of newly potentially toxic compounds, in a dissolution period 720 h. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 34001 and Grant no. 172004]

The content of some biometals (Fe, K, Mg, Zn, and Mn), and two heavy metals (Pb and Cd) in nettle (Urtica dioica L.) and in the respective soils were determined by ICP-oES. The samples were collected from two locations in the vicinity of Nis and one from w estern Serbia. The amount of vitamin C in the samples was determined by iodometric titration. The aim of the study was to determine the percentage of ful- filling the daily needs for tested biometals and vitamin C by consuming nettle as tea or as vegetable, as well as to determine the amount of biometals that plants absorb from the soil. The obtained amount of Fe, K, Mg, Zn, Mn and vitamin C suggested that nettle can be used as an additional remedy in the treatment of anemia, and to alleviate the effects due to the lack of biometals. Some biometals were absorbed to certain saturation and some for as long as they were present in the soil.

In this work we select most probable reactions of alkali metal ion Na+ with dimethoxyethane (DXE) molecule. Appropriate gas phase enthalpies of formation for the products were used to calculate scattering cross section as a function of kinetic energy with Denpoh-Nanbu theory. Calculated cross sections were compared with existing experimental results obtained by guided ion beam tandem mass spectrometry. Three body association reactions of ions with DXE is studied and compared to experimental results. Calculated cross sections were used to obtain transport parameters for alkali metal ion in DXE gas. [Projekat Ministarstva nauke Republike Srbije, br. ON 171037 i br. III 410011]

This paper presents the investigations of possibility of calcite hydrophobisation. Two samples of calcite of different size classes from the site 'Dobar kamen', Arandjelovac, Serbia, were used in the experimental work. Modifying the surface of calcite was carried out by stearic acid with 'dry' method. Concentrations of stearic acid in the modifying method were as follows: 0.3, 0.5, 0.8, 0.9, 1, 2, 2.5, 3 and 4%. The results showed that a complete hydrophobicity (I0=99.9%) of calcite sample with the medium diameter (d50) 10.87 μm was achieved at concentration of stearic acid of 0.8%, while for the sample with the mean grain diameter (d50) of 29.14 μm, it was achieved at concentration of stearic acid of 3%. These results were confirmed by the microscopic analysis.

Solving traffic problems, rather than in a conventional manner, i.e. through the construction of infrastructure and customization requirements, began to be implemented in a different way, by applying measures to motivate users to -use passenger car less, and that more of their daily activities are reached by nonmotorized modes of movement. Sustainable urban transport plans (SUP) were introduced in legislation of the EU, strategic documents that help create a better quality of life in cities. For the purposes of this study, a review of the literature related to existing plans of some major European cities was carried out, as well as small, focusing on cities of the surroundings. On this basis, the similarities and differences were ephasized in proposed measures to reach the goals of sustainable development of transportation systems. In conclusion recommendations are given on the possibility of use of experiences and applications in all the individual local communities.

Plasma etching represents one of the critical steps in manufacturing of integrated circuits. Further optimization of plasma equipment is needed since new generations in technology require different plasma chemistry. In this paper, we will study the influence of radicals on the plasma characteristics, since it was often neglected in plasma models. The radicals dominate attachment of electrons as the basic etching mixture is weakly electronegative and they also affect the drift velocity through modified momentum balance. We have used numerical solutions to the Boltzmann equation and Monte Carlo simulations (MCS) to determine the transport coefficients of electrons.

Acridine ring can be found in molecules used in many different spheres, including industry and medicine. Nowadays, even acridines with antibacterial activity are of research interest due to increasing bacterial resistance. Some acridine derivatives showed antimalarial or antiviral activity. Acridine derivatives were also investigated for antitumor activity due to the interaction with topoisomerase II and DNA base pairs. Considering these possible uses of acridine derivatives, this work was made as overview of all significant structure characteristics for specific action of these compounds.

In this paper are presented the results of testing the possibilities of improving the technological process evaluation lithothamnium limestone deposits 'Dobrilovići' - Loznica in order to obtain a new range of products including: flue gas desulphurization (ODG), as feed additive and for liming acid soils. The results showed that the limestone from this deposit may be used for ODG as it meets the requirements of the required quality for use in these purposes. In fact, the raw materials meet the requirements for obtaining a powder (bulk) gypsum. Comparing the characteristics of the resulting range to be used as a feed additive ('fodder chalk') and the requirements to be met by this product, we can say: selective excavation and selecting a particular size class can get this range of products. The results of laboratory tests of briquettes obtained from lithothamnium limestone have shown that it is possible to obtain briquettes of a satisfactory quality. Values of parameters of the mechanical properties of briquettes increases with the share of bentonite as a binder in the samples. This increase in samples with mass proportion of binder to 5% is a linear growth, while for the samples containing more than 5% of binder that trend is minimal. Therefore, there is no need to produce briquettes with more than 5% of bentonite. Based on the results of laboratory tests, authors have proposed technological scheme by which is possible complete evaluation of the limestone deposit 'Dobrilovići'. With adaptation of existing technology line in the firm Department for Agriculture 'Loznica' Ltd. (which owns the mine limestone 'Dobrilovići') can be obtained three new product range.

Over time, the transportation planing process became more sophisticated and comprehensive considering the wider range of indicatores that could affect balance between transportation supply and transportation demand. Considering urbanization and motorized traffic increase, the necessary capacity provision became a particular challenge. Therefore, it became especially important to take into account all the potential impacts that could lead to the capacity reduction. Actualization of climate change phenomenon intensified the research of weather impact in all segments of society development, including transport. Climate changes contributed to the variability of weather conditions characteristics. When it comes to the urban street network, despite the fact that even without specific research can be concluded that adverse weather conditions reduce the transport system efficiency, significant progress in reducing or eliminating consequences of that impact is not made. In this paper, the focus will be on the results of significant studies that analysed adverse weather impact on infrastructural aspect of transportation system supply, i.e. street capacity.

Climate change and changes in weather conditions have the impact on the transport system. Changes in weather conditions cause changes in the transport supply, as well as in transport demand. The first researches about weather impact on transport demand in the cities were carried out at the end of the nineties and have been intensified in the last ten years. Most of the researches about weather impact on trip generation were carried out in the countries of Northern Europe. In recent years, researches are also conducted in European countries that have climate conditions and population habits significantly different from northern European countries. This paper presents an overview of the areas in which weather impact on the trip generation was investigated. The most important conclusions of the conducted research are presented and the weather components that have the greatest influence on the trip generation are indicated. Understanding the weather impact on the transport demand is necessary for the implementation of transportation planning procedures in the upcoming climate change conditions.

This paper focuses on elements of transport policies affecting energy efficiency of road haulage. The purpose is to present a tool developed to support decision making during the policy making process, at the stage of formulating the elements of transport policies. The paper describes a model developed to assess the impact of policy instruments on fleet energy efficiency by multi-criteria ranking applying the Analytical Network Process. The paper describes the possibilities to employ the defined model giving the example of international road haulage in the Republic of Serbia. The application led to a proposal for policy instruments which could have the highest impact on the increase of energy efficiency in this sector and which will be considered further in detail during the policy formulation process. [Projekat Ministarstva nauke Republike Srbije: Development of the Model for Managing the Vehicle Technical Condition in order to Increase its Energy Efficiency and Reduce Exhaust Emissions]

The results of preparation and structural characterization of glass-ceramics from the system Li2O-Al2O3-GeO2-P2O5 are shown in this paper. The crystallization behaviour of the selected glass was examined under non-isothermal and isothermal crystallization conditions. DTA, XRD and SEM methods were employed for analyses. It was confirmed that this glass crystallizes by the volume crystallization mechanism. The results also showed that the glass crystallize by primary crystallization. As a primary phase the LiGe2(PO4)3 is formed and the traces of GeO2 as a secondary one is present. The crystallization process occurred at a high homogeneous nucleation rate and the spherical morphology of crystal growth. By applying the Kissinger relation the activation energy of crystal growth Ea = 462 kJ/mol was determined.

This paper deals with the crystallization of glass 30Li2O?15Nb2O5?50SiO2?5TiO2 (mol%). The crystallization behavior was studied under isothermal and non-isothermal conditions. XRD and SEM methods were employed for determination of phase composition and microstructure of crystallized glass. It was detected that this glass crystallizes by the surface crystallization mechanism. SEM micrographs of the crystallized samples revealed that the crystals grow in the form of dendrites. The glass-ceramics with complex phase composition was obtained. Three crystalline phases were detected where LiNbO3 has grown as primary phase and a secondary ones Li2Si2O5 and SiO2 appeared. The calculated average crystallite sizes are: 27 nm for LiNbO3 , 115 nm for Li2Si2O5 and 45 nm for SiO2 . From the experimental data an activation energy of crystals growth, calculated using the Kissinger relation, is Ea = 275 ?10 KJ / mol.

We are facing the anticipation of substantial changes in the society which offer it other valences and a new configuration. The society we know surrenders its spot to the knowledge society based on creativity and innovation, processes that assure not only a knowledge explosion but also new directions of sustainable development. This paper, by firstly clarifying the creativity and innovation concepts, intends to detect these action directions in the context of the general objectives that exist on a European Union level.

The beginning of the IIIrd millennium faces a more and more concrete threatening: exhaustion of Earth resources and the entrance in a state of collapse as long as the states of the world will not find,as soon as possible, some alternative resources that they can use in the most important fields of activities.Aeolian energy represents a solution in what concerns the exhaustion of resources of fossil fuels, but not only. Aeolian energy also represents an alternative in what concerns the protection of the surrounding environment, its noxious effects being incomparable smaller than the ones produces by conventional energy.

The kinetics and mechanism of isothermal crystal growth of K2TiGe3O9 from a glass of the same stoichiometric composition were studied. The crystal growth rate, U, in the range 1x10-11-1.27x10-10 m s-1 was experimentally determined in the temperature interval 540-600°C. In the range of high under-cooling, Δt, 435-375°C, spherical crystals growing at (374±19) kJ mol-1 was observed. Pod izotermskim uslovima proučavana je kinetika i mehanizam rasta K2TiGe3O9 kristala iz stakla istog stehiometrijskog sastava. U intervalu temperature 540-600°C eksperimentalno su određene brzine rasta kristala, U, 1x10-11-1.27x10-10 m s-1. Pokazano je da se u oblasti visokih pothlađenja, Δt, 435-375°C, rast sfernih kristala ove faze odvija po mehanizmu zavojne dislokacije. Dobijena je energija aktivacije rasta kristala GD=(374±19) kJ mol-1.

The importance of transportation modeling, especially personal car flow modeling, is well recognized in transportation planning. Modern software tools give the possibility of generating many development scenarios of transport system, which can be tested quickly. Transportation models represent a good (and necessary) basis in the procedure of environmental traffic impacts and energy emission estimation. Research in this paper deals with the possibility of using transportation modeling as a tool for estimation of some air pollution and global warming indicators on street network, produced by personal cars with internal combustion engines. These indicators could be the basis for defining planning and management solutions for transport system with respect to their environmental impacts. All the analyses are based on several years of research experience in Belgrade. According to the emissions of gases from the model, the values of other green house gases can be estimated using the known relations between the pollutants. There is a possibility that all these data can be used to calculate the transportation systems impact on temperature increase in urban areas.

All poultry is sensitive to mycotoxins. This partly depends on the type, age and production categories of poultry, their living conditions and nutritive status and partly on the type, quantity and duration of mycotoxin ingestion. The presence of mycotoxins results in significant health disorders and a decrease in production performances. This leads to considerable economic loss for the poultry industry - either direct losses, i.e. death of the poultry or the indirect ones, i.e. the decrease in body mass, number and quality of eggs, greater food conversion, and immunosuppression. Immunosuppression results in increased sensitivity to infective agents and a bad vaccinal response. Morevover, mycotoxin residues in poultry meat, eggs and products derived from them pose a threat to human health. In order to prevent and reduce the negative implications of mycotoxins in the poultry production, it is necessary to create both global and national strategies for combatting mycotoxins, advance diagnostic techniques and procedures, intensify the control of food quality, introduce new limits on the maximum amount of mycotoxins allowed in food and poultry feed used for certain species and categories of animals, and synchronise it with the European standards. Sva živina je osetljiva na mikotoksine u zavisnosti od vrste, starosne i proizvodne kategorije, uslova ambijenta i nutritivnog statusa, sa jedne strane, i vrste, količine i dužine unošenja mikotoksina, sa druge strane. Prisustvo mikotoksina rezultira značajnim poremećajem zdravlja i padom proizvodnih performansi, a samim tim i značajnim ekonomskim gubicima u živinarskoj industriji, kako direktnim, koji se očituju uginućem živine, tako i indirektnim, u vidu pada telesne mase, broja i kvaliteta jaja, veće konverzije hrane i imunosupresijom. Imunosupresija rezultira povećanom osetljivošću na infektivne agense i lošim vakcinalnim odgovorom. Opasnost po ljudsko zdravlje predstavljaju rezidue mikotoksina u živinskom mesu, jajima i proizvodima dobijenim od njih. Da bi se predupredile i smanjile negativne implikacije mikotoksina u živinarskoj proizvodnji potrebno je formirati kako globalne tako i nacionalne strategije za borbu protiv mikotoksina, unaprediti dijagnostičke tehnike i procedure, pooštriti kontrolu kvaliteta hrane, uvesti nove limite za maksimalne količine mikotoksina u hrani i hranivima za pojedine životinjske vrste i kategorije i uskladiti ih sa evropskim standardima.

A 21-day-long experiment was performed on 160 one-day-old 'Ross' broiler chicks. This research was done with the aim of investigating pathomorphological changes in broilers exposed to a relatively small amount of T-2 toxin (2 ppm) and the possibility of prevention and/or alleviating adverse effects of T-2 toxin using various feed additives. Pathohistological examination showed negative consequences of T-2 toxin in all examined organs as degenerative changes developed in small intestine mucosa, enterocites and hepatocites necroses, as well as lymphocites depletion in bursa of Fabricius. Disparately from inorganic (Minazel-plus, Mz) and organic (Mycosorb, Ms) adsorbents, which did not provoke protective effects, in liver, small intestine and bursa of Fabricius of broilers who were given feed with T-2 toxin and mixed adsorbent (Mycofix-plus, Mf), mostly preserved structure of these organs could be noted. Eksperiment je izveden na 160 jednodnevnih brojlerskih pilića provenijencije 'Ross', u trajanju od 21 dan. Istraživanja su bila usmerena na omogućavanje detaljnijeg uvida u patomorfološke promene kod brojlera izloženih dejstvu relativno niskih doza T-2 toksina (2 ppm), kao i mogućnosti prevencije ili ublažavanja štetnih efekata korišćenjem različitih adsorbenata. Patohistološkom analizom isečaka tankog creva, jetre i Fabricijeve burze, uočeni su efekti T-2 toksina u svim ispitivanim organima, u vidu degenerativnih promena na sluznici tankog creva, nekroze enterocita i hepatocita, kao i deplecije limfocita u Fabricijevoj burzi. Za razliku od neorganskog (Minazel-plus, Mz) i organskog (Mycosorb, Ms) adsorbenta čijom primenom nije došlo do zaštitnog efekta, u tkivnim isečcima jetre, creva i Fabricijeve burze kod brojlera koji su putem hrane dobijali T-2 toksin i mešoviti adsorbent (Mycofix, Mf), zapaža se uglavnom očuvana struktura ispitivanih organa.

The processes of underpotential (UPD) and overpotential (OPD) deposition of Al onto Cu(111), from the room temperature molten salt AlCl3-EtMeImCl of different compositions, has been investigated by the cyclic volatmmetry (CV) and potentiostatic pulse techniques. It was shown that the CVs of the UPD are characterized by two sharp peaks, while the potentiostatic cathodic and anodic j-t-transients of this process are characterized by two waves indicating that the UPD of Al results in the formation of two structures. The first, less dense one, most probably the (?3x?3)R30? ordered structure of Al is formed at a more positive potential of about 200 mV vs. Al, while the second one, a complete momolayer of Al, is formed at about 20mV vs. Al, just before the reversible potential of Al in these melts (-20mV vs. Al). The OPD of Al was detected at potentials more negative than -30mV vs. Al, occurring through the progressive 3D nucleation and growth mechanism. Slow surface alloying of Al with Cu was found to occur at a potential close to the reversible potential of Al.

The SnCl 4 catalyzed glycosylation reaction of peracetylated p-D-galactopyranose derivatives with terminally unsaturated C 3 -C 1 1 alkenols was used for the synthesis of some C 3 -C 1 1 alkenyl p-D-galactopyranosides, as precursors forunsaturated neutral bolaforms.

In the present paper, the preparation of 3?-hydroxy-17?-dimethyl-tert-butylsilyloxy- 5-azaandrostane (15) in fourteen steps is described. B-nor-17-oxoandrost- 5-en-3?-yl acetate (1)1,2 was used as the starting material, which was transformed to the key intermediate of the synthesis, B-nor-17?-dimethyl-tert-butylsilyloxyandrost- 4-en-3?-yl acetate (7).

In this paper the effect of the addition of Li2O on the crystallization behavior of PbO-B2O3-ZnO glass was investigated by the differential thermal analysis (DTA) and X-ray powder diffraction (XRPD) methods. The crystallization ability, as well as the crystalline phases which develop during devitrification of the glass were examined. The results of DTA and XRPD analysis showed that the addition of Li2O varies the sequence of the crystallization as well as the phase composition of the crystalline phase. The glasses with Li2O crystallize at a lower temperature (360 ºC) with 4Li2O-4ZnO-3B2O3 as the major crystalline phase. The base PbO-B2O3-ZnO glass crystallizes at 480 ºC with PbO-2ZnO-B2O3 as the major crystalline phase. . U ovom radu metodom diferencijalno-termijske analize i rendgenske difraktometrije praha ispitivan je uticaj dodatka Li2O na kristalizaciju PbO-B2O3-ZnO stakla. Rezultati ispitivanja su pokazali da uvođenje malih količina Li2O u osnovno PbO-B2O3-ZnO staklo menja tok kristalizacije i fazni sastav kristalne faze. Stakla koja sadrže Li2O kristališu na nižoj temperaturi (360 ºC) uz izdvajanje 4Li2O-4ZnO-3B2O3 kao osnovne faze. Osnovno PbO-B2O3-ZnO staklo kristališe na višoj temperature (480 ºC) uz izdvajanje PbO-2ZnO-B2O3 kao kristalne faze. .

This article presents the methodology to reconstruct images of ship hulls in turbid waters from an information gathered to a system composed of video camera, laser line-point and sonar scanning, which were incorporated into an underwater vehicle that has a navigation control. The acquired data is processed by diffuse algorithms that have demonstrated low computational complexity and high efficiency in image reconstruction. We present the results of image reconstruction of ship hulls in low visibility conditions.

In this study mechanical properties of PVC mixtures (PVC, stabilizer, lubricant, filler) such as tensile strength, tensile elongation, breaking strength, and breaking elongation were investigated. Unmodified calcite, as well as calcite modified by stearic acid, were used as fillers in wet and dry processes. The PVC mixtures containing the calcite modified by wet procedure have better mechanical properties compared to those with the calcite modified by the dry process. Tensile and breaking strength of the PVC mixture containing the calcite modified with 1.5% stearic acid using wet process, are higher for 2.8% and 5.2%, respectively, compared to the PVC mixture containing the calcite modified with the same amount of acid used in the dry process. The tensile strength difference between the mixtures increases with the increase of the concentration of used stearic acid up to 3%. The strength of PVC mixture with the calcite modified by wet process is 3.1% higher compared to the mixture containing calcite modified by dry process. The results showed that the bonding strength between calcite and the adsorbed organic component affected tensile strength, tensile elongation and breaking strength of the PVC mixtures. The best filler was obtained by wet modification using 1.5% stearic acid solution that provided the formation of a stearate monolayer chemisorbed on calcite. The PVC mixtures containing the calcite modified by wet process using 1.5% stearic acid solution exhibited the best mechanical properties. This calcite was completely hydrophobic with dominant chemically adsorbed surfactant, which means that stearate chemisorbed on calcite provided stronger interaction in the calcite-stearic acid-PVC system.

Loše reakcije na krize koje su izazvane ljudskim ili sistemskim greškama mogu značajno uticati na zaustavljanje ili prekid radnih procesa u okviru organizacije. Ove greške moguće je minimalizovati korišćenjem metoda koje su zasnovane na primeni agentnog modelovanja, odnosno agentne tehnologije. Osnovu agentnog modelovanja čini softverska i/ili hardverska realizacija sistema koji je sačinjen od nezavisnih, ali ne i izolovanih komponenti – agenata, koji imaju mogućnost samostalnog odlučivanja i komunikacije sa okruženjem, zbog realizacije zadatog cilja. Princip agentnog modelovanja primenjen je na proces edukacije, odnosno uspostavljanja, održavanja i nadogradnje sistema zasnovanog na informacionim tehnologijama (IT sistemi), i na obučavanje personala s ciljem smanjenja uticaja grešaka koje nastaju tokom krize. U radu je prikazan originalni model agenta edukacije koji je namenjen prevenciji, suzbijanju i smanjenju uticaja kriza koje nastaju kao posledica spore reakcije na incidente, neadekvatnog odlučivanja ili loše komunikacije. Agent edukacije sadrži agent indikatora stanja koji reaguje na incidente i agent menadžmenta koji je namenjen smanjenju vremena trajanja i intenziteta krize. Kroz primer fiktivne vojne organizacije VORG predočene su funkcije agenata edukacije za konkretan slučaj., Introduction Crises caused by human or system errors vary in intensity and duration, and may cause adverse changes in the functioning of an organization. The prevention as well as a good response to incidents and fast reaction to the crisis when it escalates are essential. Therefore, all decisions during the crisis must be precise and concise, and the reaction of the information and communication systems as well as that of personnel must be adequate. The agent technology described in this paper is used to model the education agent for establishing, maintaining and upgrading IT systems, as well as for the staff training. The education agent consists of an indicator of changes in the environment (status indication agent) and a management system (management agent) for the reaction to crises. Through an illustrative example of the VORG organization, the functions of these agents are described. Causes of IT Crises IT crises are generally caused by human or system errors. The intensity and duration of the crisis vary and cannot be predicted. Still, problems that may arise as a result of the crisis may be far-reaching for an organization. However, well educated staff and a high-quality IT infrastructure can minimize errors and reduce the consequences for the organization. Agent-Based Modeling An agent is a software or hardware memory-based component that can be implemented in an information system. It can independently make decisions and communicate with the environment. It also receives, processes and transmits information in accordance with existing protocols, and its validity is determined by the ability to adapt to changes. In carrying out the activities it is characterized by a certain form of intelligence, which enables the agent’s response to be directed towards the realization of objectives. Agent-Based Modeling of Education With proper education, there is a possibility for employees to avoid some mistakes that lead to crises. However, crises can occur due to unforeseen events. If the crisis management and incident indication are the parts of a business plan, then a proper training increases resistance to human and system errors. Therefore, the management agent and the status indication agent, i.e. the education agent, are used to train personnel, make information concise and decisionmaking faster when a crisis hits. Moreover, the education agent also monitors, controls and upgrades IT-based systems. The status indication agent is realized as a software module for a rapid response to the occurrence of incidents. High speed indicates a need for the selection of one of the options defined in advance in the initial phase of the education agent. The indication is based on symbolic logic. If the agent does not recognize one of possible options, it reacts by alarming the person in charge. The management agent is a synonym for the crisis management processes. When setting the initial conditions for the management agent, it is necessary to define how and when to use the information needed in a given situation, which is performed by forming the matrix of responses to the if-then kind of questions. In that way, it is possible to reduce the duration and intensity of the crisis. Education agent: Education includes the establishment, maintenance, upgrading IT systems and staff training. The initial settings of an organizational structure also mean that the basic parameters of an education agent and its functions are also initalized in order to provide a proper reaction to the incident and, consequently, the crisis. As a part of the education agent, the status indication agent is used to notify and recognize incidents, while a proper reaction to the crisis is a function of the management agent. After the crisis ends, the education agent is used to return the operational capabilities and make changes in the organizational structure. Example of an Error Impact Reduction for the Vorg Military Organization THE VORG, An imaginary military organization, is a three-level structure consisting of managers, executives and employees. The VORG’s functions include implementing new IT systems and maintaining the existing ones, co-operating with other organizations and scientific research. In that way, the sources of crises in the VORG can be inadequate response to incidents, poor communication and education following the inadequate decision-making. The crisis caused by an inadequate response to the occurrence of incidents: The reaction to the occurrence of incidents is important for each function in the organization. A reaction to the crisis depends on the quality of IT systems, and the way the employees cope with crises. In this case, the education agent functions are primairly a periodic check up (announced or unannounced) on the employees and the incident-response systems as well. The crisis caused by an inadequate communication and education: In organizations with an inflexible hierarchy, the employees have to recognize a crisis, but they are also required to respect the rules when addressing the superiors. An organization has to be prepared for the events that could cause a crisis. This is enabled by the initial state activities. In this example, the education agent is used to forward only important information to the collegium. The crisis caused by an inadequate decision making: Decision making is mostly related to the supervisors and the executive staff. During the crisis it is necessary that the supervisors let the emergency teams make decisions. It is also essential that the decision-making staff is tested and that their work is revised by accredited experts. One way of checking the competence is to introduce certain deadlines and demands for the personnel that should be a part of the top management. Conclusion Many different errors can cause crises that vary in intensity, duration and consequences. Educating staff, checking their skills and a qualitative structure of an organization represent the basis of a quick and accurate response to a crisis. Nevertheless, human errors as well as system failures may happen. These errors can be prevented by the functions of the education agent which consists of a status indication agent and a management agent. The education agent is realized as a software or hardware-based module which functions at a basis for the IT system activities before, during and after the crisis. The causes of crises are inadequate responses to the occurrence of incidents, inadequate communication and education as well as inadequate decision making, which is explained in details in the illustrative example of the VORG organization.

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For a quasilinear operator on the semiaxis a reduction theorem is proved on the cones of monotone functions in Lp - Lq setting for 0 < q < ∞, 1

Tehnike prenosa signala u proširenom spektru sa direktnom sekvencom predstavlja efikasan metod zaštite upravljačkog signala bespilotne letelice (BL). Zaštita signala se ostvaruje primenom pseudoslučajnih (PS) sekvenci u predajniku, koje su poznate prijemniku, ali ne i neovlašćenom korisniku. Da bi se ostvario pouzdan prenos signala, PS sekvence treba da imaju dobre autokorelacione osobine. Ukoliko je prenos signala realizovan primenom nekoliko PS sekvenci, tada su od velike važnosti i njihove međukorelacione karakteristike. U radu su analizirane autokorelacione i međukorelacione osobine PS sekvenci dužine 255. Razmatrane su tri najčešće korišćene klase PS sekvenci: linearne sekvence maksimalne dužine, Goldove sekvence i Kasamijeve sekvence. Predložen je optimalan skup PS sekvenci za zaštitu upravljačkog signala BL., The Direct Sequence Spread Spectrum technique represents an effective method for unmanned aerial vehicle (UAV) control signal protection. Signal protection is obtained by applying pseudorandom (PR) sequences within a transmitter, known by a receiver, but unknown to an unauthorised user. In order to achieve reliable signal transmission, PR sequences ought to have good autocorrelation properties. If the signal transmission is realized by using several PR sequences, their crosscorrelation properties are of high importance as well. In this paper autocorrelation and crosscorrelation properties of PR sequences of length 255 are analyzed. Three most frequently used classes of PR sequences: linear maximum length, Gold and Kasami sequences are considered. An optimal set of PR sequences for UAV control signal protection is recommended.

In the trial, in vitro HPTLC - High Performance Thin Layer Chomatography was used to determine the amount of 'free', i.e. unbound or non-decomposed T-2 toxin. Mean adsorption or degradation levels of T-2 toxin in examined feed aditives, in in vitro conditions, ranged from 26.06 to 34.84% and did not significantly differ among used adsorbents: inorganic (Minazel plus - Mz), organic (Mycosorb - Ms) and mixed (Micofyx - Mf). All these additives showed better adsorption ability in the acidic environment (pH3). In vitro ispitivanjem određivana je količina 'slobodnog' tj. nevezanog ili nerazgrađenog T-2 toksina tehnikom tankoslojne hromatografije (HPTLC - High Performance Thin Layer Chromatography). Prosečne vrednosti adsorpcije ili degradacije T-2 toksina ispitivanim adsorbentima u uslovima in vitro nisu se značajnije razlikovale u zavisnosti da li je bio umešan neorganski (Minazel plus, Mz), organski (Mycosorb, Ms) ili mešoviti adsorbent (Micofyx, Mf) i iznosile su od 26,06 do 34,84%. Svi ispitivani adsorbenti su pokazali veću sposobnost adsorpcije ovog toksina u kiseloj sredini (pH 3).