Vojnotehnicki glasnik / Military Technical Courier

20-45

Authors: Gaćeša Nebojša N., Jovanović Zvezda D.

This article presents a jubilee which the scientific review Military Technical Courier marks in 2012 - the sixtieth anniversary of regular and continuous publication. The retrospective of marking jubilean anniversaries in the past 60 years offers the evidence of persistent and thorough efforts to develop and improve the quality of the Courier's content. The article shows the great dedication of editor's offices and editorial boards as well as the invaluable scientific and professional contribution of numerous authors. The article also deals with today's positions and achievements of the Military Technical Courier which, according to the classification of the Ministry of Education and Science of the Republic of Serbia, belongs to the national category of scientific journals.

59-81

Authors: Perić Sreten R.

The need for more effective maintenance and possibility of continuous exploitation of equipment has developed numerous strategies and methods for machinery maintenance. The maintenance strategy by condition, that requires continuous monitoring and equipment overlook, has initiated the development and use of lubricant analysis. Monitoring the performance of lubricants in practical application has multiple significance for both the consumer and the lubricant manufacturer. The primary significance for the consumer is extended life and timely change of lubricants, which keeps the costs of maintenance down. The lubricant manufacturer gains by creating a partner relationship with the consumer, as well as creating the possibility of gathering information about the performance of his product which will serve as a foundation for the further improvement and development of his product. If we wish to maintain technical systems so that they have as little halts and costs caused by halt removal or system failure as possible, we must monitor data indicating equipment condition throughout the system operation. It is especially difficult to obtain data on equipment condition for parts which cannot be observed due to their position. In such cases, oil analysis enables a continuous equipment condition monitoring and timely response in order to prevent undesirable prolonged halts.

102-116

Authors: Andrejić Marko D., Milenkov Marjan A.

In practice, there are several approaches in discussing the achieved level of development of a scientific discipline. One group of them concentrates on external indicators of the development of a scientific discipline, i.e. its research network, while the other group analyzes the science structure, i.e. its elements. The achieved level of the development of the defense system and its (external and internal) environment, general knowledge on the development and the systematic treatment of science as well as the present situation in the society require an insight into the internal and external indicators of the development of defense logistics as a scientific discipline (Defense Science). General knowledge on the creation, development and interdependence of sciences as well as internal and external indicators of the achieved development level of Defense Logistics show that it should be developed in the network environment as a multidisciplinary science, in close cooperation with other special disciplines of logistics, within defense science. It could thus contribute to the improvement of the defense as an important public function as well as to closer contacts of the scientific disciplines dealing with technical systems and technologies with the so-called. orthodox military disciplines.

133-146

Authors: Indic Dejan R.

The paper presents a draft of a system model for responding in case of chemical accidents in accordance with the current legislation regarding the environment protection, the structure and elements of the existing response system in case of chemical accidents, other works dealing with the issue as well as the prospects planned by those responsible for the environmental protection. The paper discuss the possibilities of different institutions and agencies of the Republic of Serbia to engage in specialized methods of cooperation and protection against chemical hazards in accordance with Article X of the Convention on the Prohibition of Chemical Weapons.

165-178

Authors: Bakrač Saša T., Milanović Miško M., Marić Mirjana J., Marković Srđan S.

This paper proposes an appropriate methodology for ecological risk assessment. The methodology has been applied in the region of Boka Kotorska Bay (Bay), Montenegro. The emphasis of the research is on the analysis of the impact of various stressors on the ecological components of Bay. The consequences of that impact can be seen in an increased level of eutrophication of water environment, mostly through the influence of nitrogen and its compounds. The actual research at/about the region of Boka Kotorska Bay was performed in the period of 2008. The study emphasized the importance of the acquisition, processing and analysis of various ecologically related data for more efficient monitoring and management of the environment. The suggested methodology of the ecological risk assessment is, therefore, a remarkable scientific and expert contribution in the area of environmental protection in our country and in general.

196-210

Authors: Osmokrović Nikola S., Vukašinović Ratko R., Zinaja Dragiša D.

The main aim of introducing information technology into the armed forces is the automation of the management process. The management in movement and transport (M&T) in our armed forces has been included in the process of automation from the beginning. For that reason, today we can speak about the automated processing of data on road traffic safety and on the use of motor vehicles. With regard to the overall development of the information system of the movement and transport service, the paper presents an information system of the M&T service for the processing of data on the use of motor vehicles. The main features, components and functions of the 'Vozila' application, which was specially developed for the automated processing of data on motor vehicle use, are explained in particular.

230-236

Authors: Stopić Srećko R., Milivojević Milovan S., Diković Ljubica Z.

The First Scientific Conference 'Higher Education and effective business management- challenges of sustainable regional development' was held on 20-21 December, 2006, in Užice, Republic of Serbia. More than 90 papers were presented. The number of authors and coauthors was 150. The Second Scientific Conference 'Economy development and effective business management - challenges of sustainable regional development' - was held upon the initiative of the management of the High Business Technical School of Užice on the occasion of its 30th anniversary It was held on 21-22 January 2007, in Užice, Republic of Serbia. Eighty papers were presented at the Conference. The number of authors and coauthors was 140. After that, the management of the High Business Technical School of Užice decided, for the first time, to organize an International Conference. The first International Conference 'Science and Higher Education in Function of Sustainable Development'. SED 2008 was held on 17-18 September, 2008, in Užice, Serbia. Ninety papers were presented on the Conference. The number of authors and coauthors was 150. The second International Conference 'Science and Higher Education in Function of Sustainable Development'. SED 2009 was held on 14-15 September 2009, in Užice, Serbia. More than 80 papers were presented. The number of authors and co-authors exceeded 100.

260-263

Authors: Uredništvo

The article does not contain abstract.

42-70

Authors: Demić Miroslav D., Glišović Jasna D., Miloradović Danijela M.

Calculation and testing methods of drum brake mechanisms are presented in a large number of papers. Intensive development of computer techniques, numerical methods and measurement techniques make a significant contribution in this domain. Based on the conducted analysis, it is obvious that there is no generally accepted method for the evaluation of mechanical characteristics and output parameters of drum brakes. One new approach for defining evaluation criteria of the properties of drum brakes for motor vehicles is presented in this paper. The complex characteristics of various types of brake mechanisms are formed according to the proposed algorithm, the fast assessment of the characteristics of the brake mechanism is performed, which is especially important in the development phase of new products, by using computer techniques for measuring, data acquisition and data processing.

90-108

Authors: Andrejić Marko D., Milenkov Marjan A., Andrejić Ivana M.

Major organizational changes occurring during the last decade in the state and the current social moment require an adequate social determination of the defense as an important state function, having in mind its qualitative level of study, scientific research and logistical sustainability. The role and importance of the logistic support of defense, range and quality of resources that it engages, the practical needs, time requirements and current trends require a treatment of the defense at a higher level of consideration in education, research and operational practice. When considering the development level of any science and the work on its development, we should monitor continuously and analyze objectively the development and influence of the dominant forms of social consciousness - religion, philosophy and particular sciences (natural and social) - and review the basic constituents of the science development. It is also necessary to understand the essence of the relationship between science and philosophy, science and politics, and science and art. A large number of authors (under the influence of methodological essentialism) consider that each science at its lowest level of development (with the exception of philosophical assumptions that are implicit) must have four basic constituents: its subject, theory, language and methodology. Based on the development of the above constituents, these authors assess the level of the scientific development of the particular science, i.e. scientific discipline.

125-142

Authors: Drenovac Aleksandar Ž., Drenovac Bratislav Ž.

This paper proves that the application of the PROMETHEE method, one of better known methods of multicriteria optimization, can be used as a generalized criterion for many different situations when solving diverse problems and at all levels of the military organization. The decision-making process can be simplified, resulting in a higher level of reliability of decisions of the Ministry of Defence and higher levels of command in Serbian Armed Forces while solving important multicriteria problems above all.

168-187

Authors: Petrović Nikola Č., Đedović Branko N., Petrović Dragana N.

With the desintegration of the former Yugoslavia, the needs for military technique had been significantly reduced. The capacities that exceed the scope and the structure of these needs, for which an export-oriented production would be economically sustainable, should be redirected to the production of regular consumption products. Following the practice of developed countries with multinational character projects and cooperative production of complex military assets would increase the opportunities for such a redirection. That orientation would go in favor of the prevention-based defense policy which is the strategic orientation of our country. Moreover, self-reliance in the production is viable only for some weaponry and military equipment where the economy reaches a full production scale and for which there is a possibility of export. The aim of this study is to show the need for analyzing the socialeconomic sustainability of developing and producing complex weapons and military equipment in a joint venture with the countries in the region and beyond, without jeopardizing the security of the country's current and sustainable security. This analysis is a useful tool not only for rating the project's accceptability, but also for selecting the best alternative among several project variants. It is not possible to monetize entirely the effects of benefits for a society correlating with the introduction into service of complex combat systems; therefore, a cost benefit analysis and multicriteria analysis are used for the evaluation of investment profitability. In the context of the object and purpose of the research, the methods of analysis and synthesis are used as well as the investment evaluation method. A graphic illustration and four tables are given in order to clarify the author's views.

207-215

Authors: Stefanović Radiša R.

The paper analyzes the flow of some multimedia services, and points to the possibility of applying some of the services in the broadband environment to improve the logistic needs of the army. The need to convey information in different forms (from text, data, graphics, still pictures to video motion pictures) is increasing continually. Requests for information transfer in high resolution require increasing the flow to several dozens of Mb/s. Broadband represents the platform for a wide range of multimedia services. Each multimedia service requires a certain flow which can be partially decreased with advanced coding techniques.

7-27

Authors: Mijatović Ivan B.

The article sheds light on the origins of the military technical thinking in the military publishing of the Kingdom of Serbia with a view to marking a jubilee - the sixtieth anniversary of the Military Technical Courier. 'Vojin', the first military review, printed in the middle of 19th century as a private venture, covered a wide scope of military issues, among which a special place was given to 'the science of weapons'. No sooner had this review ceased to exist than The Headquarters of the Army of the Kingdom of Serbia started publishing a new military review, 'Ratnik', which, apart from the art of war and war literature, dealt with the science of weapons in order to inform officers about the latest achievements in military technology and to educate them as well. Serbian military thinking, including its technical aspect, did not fall behind modern trends in its European and world counterparts until 1914. The development of weaponry in Europe and the world was regularly covered on the pages of military reviews.

48-70

Authors: Milićević Milić R., Župac Goran Ž.

This paper presents the methods of the subjective approach in determining the criteria weights. The compensatory and noncompensatory methods for determining the criteria weights are briefly summarized. Determining the criteria weight using pairwise comparisons and rankings is elaborated in detail. Possible ways of determining the criteria weight in a group environment are presented in the last part of the paper. A subjective approach includes an impact of the decision maker on the criteria weights, and therefore on the final solution of multicriteria problems. In contrast to the objective approach, some methods of the subjective approach do not require the existence of a decision matrix. The main aim of this paper is a systematic review of possible ways of determining the criteria weights by the decision maker or more participants in the decision process.

84-117

Authors: Mladenović Dragan D., Jovanović Danko M., Drakulić Mirjana S.

Cyber conflicts represent a new kind of warfare that is technologically developing very rapidly. Such development results in more frequent and more intensive cyber attacks undertaken by states against adversary targets, with a wide range of diverse operations, from information operations to physical destruction of targets. Nevertheless, cyber warfare is waged through the application of the same means, techniques and methods as those used in cyber criminal, terrorism and intelligence activities. Moreover, it has a very specific nature that enables states to covertly initiate attacks against their adversaries. The starting point in defining doctrines, procedures and standards in the area of cyber warfare is determining its true nature. In this paper, a contribution to this effort was made through the analysis of the existing state doctrines and international practice in the area of cyber warfare towards the determination of its nationally acceptable definition.

139-155

Authors: Radojević Slobodan M.

This paper presents the conditions for using floating cranes for lifting sunken vessels and other objects on inland waterways. Basic technical data are given together with technical details for the usage of floa ting cranes for lifting sunken objects. The paper points to the importance of lifting sunken objects and their removal from inland waterways in the Republic of Serbia.

182-201

Authors: Mrdak Mihailo R.

The aim of this study was to examine the properties of Ni22Cr10Al1Y layers in order to obtain optimal structural - mechanical properties with the optimization of depositing parameters. Powder was deposited by the atmospheric plasma spray (APS) process with the current intensity of 600, 700 and 800A, with a corresponding plasma gun power supply of 22KW, 34KW and 28KW. The evaluation of the Ni22Cr10Al1Y coating layers was made on the basis of their microhardness, tensile strength and microstructure performance. The best performance was obtained in the layers deposited with 800A and the 34KW plasma gun power supply. The coating with the best characteristics was tested to oxidation in the furnace for heat treatment without a protective atmosphere at 1100°C for one hour. The examination of the morphology of Ni22Cr10Al1Y powder particles was carried out on the SEM (Scanning Electron Microscope) as well as the EDS analysis of the best layers. The microstructure of the deposited coating layers was examined with a light microscope. The microstructure analysis was performed according to the TURBOMECA standard. The mechanical properties of layers were evaluated by the method HV0.3 for microhardness and by tensile testing for bond strength. The research has shown that plasma gun power supply significantly affects the mechanical properties and microstructure of coatings that are of crucial importance for the protection of components exposed to high temperature oxidation and hot corrosion.

216-234

Authors: Borisov Mirko A., Banković Radoje D.

In this study, the Earth's curvature is analyzed from numerous aspects as well as the visibility between two points on the Earth's surface. It also describes the way and the size of the Earth's part which can be approximated in the plane depending on the graphical precision and the scale of topographic maps. It equally considers the possibility of visibility between two points on the Earth's surface depending on the relief shapes and the curvature of the Earth's surface applying both classical methods and sophisticated solutions.

245-257

Authors: Pavić Aleksandar M., Nikolić Veljko Z.

Possibilities to use retrodirective antennas in modern radar systems are presented in this paper. The basics of retrodirective theory, practical realizations of retrodirective arrays using corner reflectors, Van-Atta and heterodyne elements are considered. A model of a retrodirective radar for automatic target tracking is presented as well as the differences between commonly used phase arrays and retrodirective arrays with simpler, cheaper signal processors and faster target detection, as mayor advantages of this technology. Its advantages and disadvantages are explained. In the end, some possibilities for this technology application are discussed as well as further research trends.

275-295

Authors: Inđić Dejan R.

This paper presents one possible way of deploying detachments for neutralizing the effects of chemical attacks in a brigade defense zone. The detachment composition is provisional and depends on the assessment of whether the enemy in the incoming combat will use weapons of mass destruction. A detachment consists of several organizational units: medical care forces, chemical reconnaissance forces, forces for the establishment of combat efficiency and chemical decontamination forces. The capabilities of the mentioned forces depend on their size, equipment, training level, extent of effects and combat conditions. The paper indicates a potential to overcome the gap in the provisions after disbanding the Army Corps.

306-322

Authors: Vasin Ljubislav T.

The paper points out to the contribution of quality standard application in all areas of human life. The detailed explanations of terms quality, product and service are given as well. Considering the fact that a result of the transportation activity is a change of the product location - transportation, the paper gives special attention to the service. A focus is also on the term transportation service, as well as the parameters of quality of transportation for passenger and cargo transportation service. In the closing section, the application of quality standards in the Serbian Army will be briefly discussed.

343-350

Authors: Glavač Boris T.

Previous experience in the correction of flat feet consisted of the use of insoles for shoes and exercises with toys, balls, rollers, inclined planes, etc. A device for strengthening foot muscles is designed for the correction of flat feet in children and, as its name suggests, for strengthening foot muscles in adults. The device is made of wood and metal, with a mechanism and technical solutions, enabling the implementation of specific exercises to activate muscles responsible for the formation of the foot arch. It is suitable for home use with controlled load quantities since it has calibrated springs. The device is patented with the Intellectual Property Office, Republic of Serbia, as a petty patent.

7-13

Authors: Gaćeša Nebojša N.

In 2012, the Military Technical Courier, a scientific journal of the Ministry of Defense of the Republic of Serbia, marks the 60th anniversary of its regular and continuous publishing. The Military Technical Courier was founded by a decree of the Chief of the General Staff of the Yugoslav Army in August 1952 in order to continue the tradition of five reviews of military branches and services (Artillery Courier, Tank Courier, Military Engineering Courier, Courier of Communications in the Yugoslav Army and Logistics and Support of the Yugoslav Army) which had been covering tactics and technique issues from 1947 to 1952. According to the founding act, the main tasks of the Military Technical Courier were 'to consider and study issues regarding armament, technical and other material equipment of the branches and services concerning the knowledge of the materials, their handling, application, effects, storage, repair and upgrading as well as to deal with technical issues of the organization, war experience of logistic services and military traffic and evacuation'. Chief of the General Staff's decree of 16th December 1952 founding the first editorial board that 'has a directive to be responsible for the review editing' was followed by the first issue of the Military Technical Courier in January 1953. The Military Technical Courier will pay special tributes to the military technical publications published in our country before 1945 (in the Kingdom of Serbia, Kingdom of Serbs, Croats and Slovenians and later the Kingdom of Yugoslavia). The following reviews represent the foundations of the Serbian military technology reasoning: Artillery and Engineering Courier (1905-1906), Artillery Courier (1926-1932), Infantry and Artillery Courier (1933-1941), Engineering Courier (1929-1940), Aviation Courier (1927-1941) and Nautical Courier (1933-1940). There is no doubt that their quality and professional profiles paved also the way to today's Military Technical Courier; however, unfavorable historical reasons pushed them unfairly into the background of our memories. We are proud to continue their tradition as well. The journal has been publishing papers dealing with military technical resources and provisions as well as with development, production and exploitation of weapons and military equipment, enhancing its reputation in both military and civilian structures. The journal has developed from a publication for the education of officers in the period of scarce adequate military technical literature to a professional and scientific journal presenting scientific and technical achievements and information important for the development, production and exploitation of weapons and military equipment. The journal's structure, sections and areas of interest have changed with respect to the Army's technical and organizational development and modernization, following the journal's conceptual and editorial policy. During its 60 years of existence, the journal has been changing its characteristics, form and content, aiming to meet the requirements of both practice and science. From 1952 to 1961, it was a professional review for weapon military equipment and supply; until 1966, it was a professional review of the YA branches and services and a YA professional journal onwards. Owing to its editorial policy, the journal continued to improve its conception, orientation, quality and position thus becoming a scientific and professional periodical highly regarded not only in military circles but in academic and scientific circles in the country as well. It has held the title of a professional and scientific journal since 1989. According to the Opinion of the Ministry of Science and Technological Development No 413-00-1201/2001-01 of 12th September 2001, the Military Technical Courier is a publication of special interest for science. Being classified as a scientific journal of national interest by the Ministry of Education and Science of the Republic of Serbia, the Military Technical Courier is today a scientific journal publishing scientific and professional papers from the following categories: mathematics, information science and mechanics, electronics and telecommunications, mechanical engineering, materials and chemical technologies, industrial software and information technologies, geosciences and astronomy. The journal is in the Serbian Citation Index - SC index and is constantly monitored depending on the impact within the base itself and on the international (Thompson-ISI) citation indexes. Since 2011, an electronic edition of the Military Technical Courier has been available at www.vtg.mod.gov.rs in Serbian, Russian, English, German and French. Since 2012 editorial applying the on-line Electronic Editing (e-Ur) system (http://scindeks-eur.ceon.rs/index.php/vtg) developed by the Center for Evaluation in Education and Science (CEES). The application of the e-Ur service shows the readiness of the Military Technical Courier, supported by IT technology, authors and the CEON, to endure in making constant advances in the influence, quality and internationalisation of papers, the journal and the Scindex base, including the progress in adherence to international ethical and publishing principles. As a unique and competent publication on a national level, the Military Technical Courier publishes and verifies scientific and professional papers, those of the members of the Ministry of Defence and the Army of Serbia in particular, who thus have the opportunity to quantify their scientific and research results. The Military Technical Courier will continue to represent the scientific potential of the Army of Serbia and the Ministry of Defense of the Republic of Serbia and to support the efforts of institutions and individuals aiming at solving existing problems and making improvement in all areas of military technical science. Nowadays, the Military Technical Courier is not only an institutional resource being developed within the defense system from 1952, but also a brand of national interest. It has therefore become an open forum for the publication and stimulation of innovative thinking about all aspects of science and technology, coming from not only the Army and MoD members, but from the national and international community as well.

39-56

Authors: Milić Milićević R., Župac Goran Ž.

This paper presents an objective approach to determining criteria weights that can be successfully used in multiple criteria models. The methods of entropy, CRITIC and FANMA are presented in this paper as well as a possible combination of the methods of objective and subjective approaches. Although based on different theoretical settings, and therefore with different algorithms of realization, all methods have a decision matrix as a starting point. An objective approach to determining the weight of criteria eliminates the negative impacts of a decision maker on criteria weights as well as on the final solution of multicriteria problems. The main aim of this paper is to systematize description procedures as a kind of help when encountering a problem of determining the criteria weights for solving multicriteria tasks. A possibility of the method application is shown in a numerical example.

70-98

Authors: Mladenović Dragan D., Jovanović Danko M., Drakulić Mirjana S.

Cyber warfare is a specific new form of military conflicts the use of which is growing rapidly in the international community. However, its nature is specific and differs from all previously known forms of warfare. For the purpose of clear understanding of the nature of cyber warfare, this paper covers the basic groups of preconditions for its broad application and fast development from technological, military and social aspects. Understanding the true nature of cyber warfare is a necessary condition for building national capacities for its application that are military justified and harmonized with the international law. The paper explores the characteristic instances of cyber warfare, ranging from information propaganda to physical destruction, with the goal to determine guidelines for the possible development of cyber capacities at the national level. Based on the analysis of previous cyber warfare cases, a prediction of future development directions is made and the necessity to apply suitable methods and techniques for defense against them is analyzed.

115-135

Authors: Ćuk Danilo V., Abobaker Mostafa H.S., Mandić Slobodan D.

Modern tactical surface-to-surface missiles, equipped with strapdown inertial navigation systems, achieve very good accuracy compared with free-flight rockets. The probable range dispersion mainly depends on instruments errors and longitudinal disturbances such as rocket motor total-impulse deviation as well as differences between the estimated and actual values of the axial force and head wind. This paper gives an extension of the correlated velocity concept for surface-to-surface missiles without a thrust-terminating mechanism. The calculated parameters of the correlated velocity are stored into the memory of an onboard guidance computer. On the basis of the correlated velocity concept, the modified proportional navigation with the adjustment of the time-to-go of the missile to the target was proposed. It is shown that the new guidance law can compensate for the longitudinal disturbances of different levels successfully. The effectiveness of the proposed guidance method was confirmed by means of the calculated probable range and lateral dispersion for the anticipated disturbances in the guidance system.

152-168

Authors: Đurđević Mile B.

The modeling of casting processes has remained a topic of active interest for several decades, and availability of numerous software packages on the market is a good indication of the interest that the casting industry has in this field. Most of the data used in these software packages are read or estimated from the binary or multi-component phase diagrams. Unfortunately, except for binary diagrams, many of ternary or higher order phase diagrams are still not accurate enough. Having in mind that most of the aluminum binary systems are very well established, it has been tried to transfer a multi-component system into one well known Al-Xi pseudo binary system (in this case the Al-Si phase diagram was chosen as a reference system). The new Silicon Equivalency (SiEQ) algorithm expresses the amounts of major and minor alloying elements in the aluminum melts through an 'equivalent' amount of silicon. Such a system could be used to calculate several thermo-physical and solidification characteristics of multi component as cast aluminum alloys. This lends the model the ability to make predictions of solidification characteristics of cast parts, where cooling rates are slow and the solidification process has to be known in great detail in order to avoid problems in the casting. This work demonstrates how the SiEQ algorithm can be used to calculate characteristic solidification temperatures of the multi-component hypoeutectic Al-Si-Cu alloys as well as their latent heats. SA statistical analysis of the results obtained for a wide range of alloy chemical compositions shows a very good correlation with the experimental data and the SiEQ calculations.

183-200

Authors: Mrdak Mihailo R.

This paper analyzes the influence of plasma spray parameters on the microstructure and mechanical properties of NiCrBSi coatings deposited by the atmospheric plasma spray (APS) process. The microstructure and mechanical properties of plasma spray coatings are determined by the interaction of plasma ions with powder particles when the rate and temperature of plasma particles are transferred to powder particles. The interaction effect directly depends on the time the powder particles spend in plasma, and that time is defined by the deposition distance for each type of powder, depending on the grain size, melting temperature and specific mass. In order to obtain homogeneous and dense coatings, three distances (70,120 and 170 mm) from the substrate were used in the research. The coating of the best structural and mechanical characteristics was remelted and fused to the base in order to obtain a better structure. Self - fluxing NiCrBSi alloys are widely used because of the good resistance of boride, carbide and silicide solid phases to wear and corrosion. The morphology of powder particles was examined in the SEM (Scanning Electron Microscope), while the microstructure of the layers was assessed using a light microscope. The microstructural analysis of the deposited layers was performed in accordance with the Pratt-Whitney standard. The mechanical properties of the layers were assessed by applying the HV0.3 method for microhardness testing and tensile testing was applied to test bond strength.

216-234

Authors: Milojević Ivan S., Guberinić Rade V.

If demand is known for the whole planning period (complete information), then this type of demand or a supply system is deterministic. In the simplest cases, the demand per time unit is constant. If demand levels change over time following a precisely determined and pre-known principle, this type of demand is also classified as deterministic. This quality of demand is very rare. In most cases demand is the product of a process, for example TMS maintenance, whose progression cannot be predicted due to a number of factors influencing the process and causing random demand changes. In this case, a supply system must function according to the complete information and with a certain degree of uncertainty. In cases when demand may be defined by some of the laws of the probability theory, we are talking about stochastic demand and a stochastic supply system. Demand can be described by mathematical expectation, mathematical expectation and standard deviation, probability distribution or as a random process. However, there is usually a need for the most complex description, i.e. the complex random process because both intensity of demand and the probability distribution change during the observed intervals. The level of temporal (dynamic) series is traditionally considered as a complex phenomenon consisting of four components: - basic tendency of phenomenon development - cyclical impact (long-term, 'ancient') - seasonal effects - random fluctuations. The basic tendency of phenomenon development means a long-term evolution of phenomena. A function that expresses the trajectory of changes of the basic tendency of a phenomenon development in the form of the equation is called a trend. Often, the trend involves time regression; i.e. the coefficients of the proposed functions are often determined by the least squares method. To roughly determine the coefficients of the proposed function, the sum of three and three-point methods are also used. After checking the hypothesis of the existence of phenomenon change trends, the next step in the methodology of forecasting is the determination of a specific growth curve that describes the regularity of the development in time. These curves of growth are obtained by the analytical representation (expression) of dynamic lines. There are two basic stages in the process of expression and they are: - The choice of the type of curve the shape of which corresponds to the character of the dynamic order variation - the determination of the number of values (evaluation) of the curve parameters. The most widespread method of forecasting is the trend extrapolation. The basis of the trend extrapolation is the continuing of past trends in the future. The simplicity of the trend extrapolation process, on the one hand, and the absence of other information on the other hand, are the main reasons why the trend extrapolation is used for forecasting. The trend extrapolation is founded on the following assumptions: - The phenomenon development can be presented as an evolutionary trajectory or trend, - General conditions that influenced the trend development in the past will not undergo substantial changes in the future. Spare parts demand forecasting is constantly being done in all warehouses, workshops, and at all levels. Without demand forecasting, neither planning nor decision making can be done. Demand forecasting is the input for determining the level of reserve, size of the order, ordering cycles, etc. The question that arises is the one of the reliability and accuracy of a forecast and its effects. Forecasting 'by feeling' is not to be dismissed if there is nothing better, but in this case, one must be prepared for forecasting failures that cause unnecessary accumulation of certain spare parts, and also a chronic shortage of other spare parts. All this significantly increases costs and does not provide a satisfactory supply of spare parts. The main problem of the application of this model is that each spare part has its own failure intensity; therefore, it is necessary to conduct a complete procedure for each part. If the average number of components of a complex asset were about 5000, along with the existence of a large number of resources, the forecasting by the trend extrapolating would practically require the newest information technologies. However, the analysis shows that in most cases 80-90% of component parts have a longer life than the asset itself. In addition, it is shown that during the life of the asset, these components do not fail, and that 10-15% of component parts have only rare failures (post optimal analysis of spare parts normative) or do not show any failing tendency meaning that failures are random. This procedure remains to be applied to 2-4% of component parts. It does not present a significant problem due to the process automation. This model enables us to determine the parts to which the trend extrapolation procedure should be applied. Forecast is obtained by the use of the second model to existing data. The trend extrapolation forecast or any other kind of forecast does not need to be done for those spare parts for which the long time forecast is close to zero. Provision of spare parts for the maintenance system considering the range, quantity, time and place is crucial for successful functioning of the maintenance system and ultimately for the accuracy of material resources. On the other hand, stocks of spare parts are costly and required to be reduced. Costs need to be minimized while ensuring the successful functioning of the maintenance system.

250-265

Authors: Markagić Milorad S.

Along with the development of confidentiality of data and resources, there is a need to develop systems that would provide confidentiality. Currently, the most used systems are classical cryptographic systems and encryption public key systems. However, none of these systems provides a solution for the famous 'catch 22' of cryptography. Owing to the intensive development of quantum mechanics, in the last 30 years emerged an entirely new kind of cryptography-quantum cryptography. Its greatest contribution is a possibility to discover an intercepted communication channel from a third party. The question is: is this really true? The question arises: 'If the quantum cryptography is so good, why is not widely used?' The aim of this paper is, on the one hand, to define the basic mechanisms of quantum cryptography IP, and, on the other hand, to point to the shortcomings, as they related to the opportunities of today's devices and flaws in protocols.

284-298

Authors: Jeremić Radun B.

In the last ten years, the Serbian Army has been facing the problem of surplus of various ordnance, which resulted from the changes in the organizational structure and rationalization. In addition, at several locations in Serbia there is still a large amount of unexploded ordnance remaining after the NATO bombing. The paper examined the environmental aspects of the destruction of surplus ammunition and unexploded ordnance. A brief survey of the methods of destruction and the technological conditions for their implementation are presented. The impact of toxic constituents of ordnance on human health and the environment is analyzed in particular. In order to minimize environmental risks during the demilitarization process of ordnance, appropriate proposals are given.

307-311

Authors: Đurković Vlado P.

The article does not contain abstract.

7-14

Authors: Pokorni Slavko J., Ostojić Dušan Đ., Brkić Dragoljub M.

The paper gives an estimation of two-terminal availability for a complex communication network (up to 50 nodes and 150 links) by a software package developed by the authors and based on the Monte Carlo simulation method and Weibull distribution. Reliability can be estimated as well. The software package is written in VISUAL BASIC 6.0 programming language on an MSI laptop with the Windows XP Professional operating system. The program execution time with over 500000 iterations is a few seconds (without graphical display). The Weibull distribution function, used for availability estimation, can be applied for electronic, electromechanical and mechanical components as well as with different failure rates.

40-61

Authors: Pamučar Dragan S.

Data envelopment analysis (DEA) is becoming increasingly important as a tool for evaluating and improving the performance of manufacturing and service operations. It has been extensively applied in performance evaluation and benchmarking of schools, hospitals, bank branches, production plants, etc. DEA enables mathematical programming for implicit evaluation of the ratio between a number of input and output performance parameters. The result is quantification of the efficiency of business opportunities and providing insight into some flaws from the level of top management. Levels of efficiency determined under the same parametres make this analytical process objective and allow for the application of best practices based on the assessment of the overall efficiency. This paper presents a fuzzy-DEA model for evaluating the effectiveness of urban and suburban public transport- USPT. A fuzzy-DEA model provides insight into the current transport quality provided by USPT and proposes for the improvement of inefficient systems up to the level of best standards possible. Such quantification makes long-term stability of USPT possible. Since most of the acquired data is characterized by a high degree of imprecision, subjectivity and uncertainty, fuzzy logic was used for displaying them. Fuzzy linguistic descriptors are given in the output parameters of DEA models. In this way, fuzzy logic enables the exploitation of tolerance that exists in imprecision, uncertainty and partial accuracy of the acquired research results.

79-92

Authors: Prodanović Radivoje M., Gavrović-Jankulović Marija Đ., Kovačević Gordana N., Blažić Marija B., Prodanović Olivera L., Raluca Ostafe V.

This overview summarizes the application of enzymes in the manufacture and design of biofuel cells and biosensors. The emphasis will be put on the protein engineering techniques used for improving the properties of enzymes such as nanobiocatalysts, e.g. immobilization orientation, stability, activity and efficiency of electron transfer between immobilized enzymes and electrodes. Some possible applications in the military and some future designs of these electric devices will be discussed as well.

116-133

Authors: Đurković Sonja V.

This paper presents a technological process and a construction of aircraft of small size and weight. The general characteristics of aircraft production are given as well as special features in aircraft manufacture. Aircraft are classified and the general characteristics of the Lasta 95 trainer-fighter are given. The technological process was especially observed and analyzed with emphasis on the technological requirements for the tools construction and the manufacture of elements and assemblies. The conclusion offers a suggestion for a technology service organization.

158-173

Authors: Hristov Nebojša P., Savić Slobodan R.

The processes occurring during the firing within barrels of weapons with combined charges are described aiming at the improvement of fire power of existing weapons and the design of new ones. The firing process simulation enables the optimization of gunpowders. The analysis of the obtained results helps in choosing the best combination of input-output parameters for the highest muzzle velocity possible while keeping powder gas maximum pressures inside the barrel at the lowest possible level.

194-207

Authors: Sokolović Vlada S., Pavlović Slaviša R., Janković Darko D.

This paper addressed several organizational models of aircraft maintenance. All models presented so far have been in use in Air Forces, so that the advantages and disadvantages of different models are known. First it shows the current model of aircraft maintenance as well as its basic characteristics. Then the paper discusses two organizational models of aircraft maintenance with their advantages and disadvantages. The advantages and disadvantages of different models are analyzed based on the criteria of operational capabilities of military units. In addition to operational capabilities, the paper presents some other criteria which should be taken into account in the evaluation and selection of an optimal model of aircraft maintenance. Performing a qualitative analysis of some models may not be sufficient for evaluating the optimum choice for models of maintenance referring to the selected set of criteria from the scope of operational capabilities. In order to choose the optimum model, it is necessary to conduct a detailed economic and technical analysis of individual tactical model maintenance. A high-quality aircraft maintenance organization requires the highest state and army authorities to be involved. It is necessary to set clear objectives for all the elements of modern air force technical support programs based on the given evaluation criteria.

248-260

Authors: Jovičić Stevan S., Mićović Aleksandar M.

Emedded nondestructive evaluation (NDE) is an emerging technology that will allow for the transitioning from conventional ultrasonic methods to embedded systems for structural health monitoring (SHM), such as those envisaged for the Integrated Vehicle Health Management (IVHM). Structural health monitoring for IVHM requires the development of small, lightweight, inexpensive systems to be embedded in the airframe with minimum weight penalty and at affordable costs. For non-destructive evaluation, PWASs can be used as both active and passive probes. The main advantage of PWASs over conventional ultrasonic probes lies in their small size, light weight, low profile, and low cost. In spite of their size, these novel devices are able to replicate many of the functions of the conventional ultrasonic probes.

272-281

Authors: Radojčić Stevan M.

Field observations refer to the vertical of the geoid, because the geodetic instruments are put in the working position in respect to the vertical. It is not appropriate for the calculations on the ellipsoid surface, which request measured elements to be referred to the normal of the reference ellipsoid. This means that the field observations must be reduced from the vertical to the normal, i.e. they must be somehow reduced from the Earth's physical surface to the surface of the reference ellipsoid. There are two methods to do this: Pizzetti's method and Helmert's method. Pizzeti's method projects the measured elements with the aid of the vertical onto the geoid surface and then, with the aid of the normal to the ellipsoid, projects them further onto the surface of the reference ellipsoid. Helmert's (or Bruns-Helmert's) method projects the measured elements directly onto the surface of the reference ellipsoid with the aid of the normal to the ellipsoid. But, until the middle of the 20th century, none of them were used. This means that the field observations were not properly reduced onto the ellipsoid's surface; they were reduced only to the geoid's surface and then used as if they were reduced to the ellipsoid. The reasons fot that are simple. On the one hand, it was almost impossible to determine the relation between the geoid and the ellipsoid at each desired point on the Earth's physical surface (first of all the geoid undulations N and the components of the deflection of the vertical î and ç), so it was very difficult to calculate the reductions. On the other hand, the consequences of neglecting the reduction from the geoid to the ellipsoid were too small, compared with the accuracy of the observations in that time.

294-300

Authors: Pokorni Slavko J.

The basic information about history, goal, significance and working areas of the international scientific and professional symposium INFOTEH- JAHORINA are given in this paper. This year's symposium INFOTEH- JAHORINA 2011 is described in detail (number and structure of papers, basic information about each working area, and reviews of certain papers). The information on the availability of proceedings of this year and former symposiums is given as well.