Machines. Technologies. Materials.
Vol. 9 (2015), Issue 6

Table of Contents

  • DISPERSION MODELING AND ASSESSMENT OF AIR POLLUTION WITH PARTICULATE MATTER (PM10) IN URBAN AREAS OF CENTRAL NORTH BULGARIA

    pg(s) 3-6

    The dispersion model and assessment of air pollution by particulate matter (PM10) are developed in accordance with the requirements of the Bulgarian legislation and the Framework Directive 96/62 / EC on the assessment and management of air quality (AAQ). The input data of the model was based on an assessment of the sources of air pollution in three urban areas of Central North Bulgaria – Svishtov, Sevlievo and Gorna Oryahovitsa, defined as point, area and line sources of PM10.

    The results of the modeling and assessment of air pollution in the studied urban areas of Central North Bulgaria for 2007- 2010, show that local air pollution with PM10 from domestic heating of solid fuels is a major factor for dust pollution of air in them.

  • NFC – THE FUTURE OF e-SMART BUSINESS

    pg(s) 10-12

    Near Field Communication (NFC) technology is the future of m-Commerce, which has found possible application in contactless cards and mobile phone devices. NFC is technologically integrated with Data Ware House infrastructure and Cloud computing system which are incorporated in the e-Smart Business system. As a product of the implementation of NFC technology in m-Commerce business models there is a need of expansion B2B2C business model towards integration of services with the aim of creating new products, markets and consumer needs tuning. This paper presents a business model called e-Smart-Business as a system integration concept of m- Commerce through direct marketing and market research with the Data Ware House and Cloud computing systems.

  • SCP-RPSC – THE KEY TECHNOLOGY FOR THE NEXT GENERATION MICROWAVE COMMUNICATION SYSTEMS

    pg(s) 13-16

    A retrospective review of a new technology, named SCP-RPSC, is given in this report. It is particular useful as the radio front end of the microwave communication systems with terrestrial and satellite positioning. SCP (Spatial Correlation Processing) technology includes additional pilot signal transmitted in the band of information signals and available in the receiver by one of the known methods of radio access. The receiver terminal is equipped with random phased antenna array. The random phase spread information and pilot signals correlate in a correlator. Its output signal at baseband is the recovered information signal. The application of SCP principle in transmit mode was named RPSC (Random Phase Spread Coding). The transmitted by the random phased antenna array signals have specific phase spread. It can be considered as random spatial coding. The advantages of the SCP-RPSC approach over classic microwave communication systems, based on phased antenna arrays, are shown. A list of possible communication applications as Satellite Digital Video Broadcasting , Inter Satellite Links, Feeder Lines, High Altitude Platform Systems, WIMAX, Aeronautical and Global Navigation Satellite Systems (GNSS) is given too.

  • SPACE CORRELATED U-PN CODES – A POSSIBLE SOLUTION FOR THE NEW MICROWAVE COMMUNICATION AND RADAR SYSTEMS

    pg(s) 17-20

    A retrospective review of a new approach, named Space Correlated U-PN codes, is given in this report. It is particular useful as spread spectrum radio access technology in the mobile broadband communication and radar systems with integrated terrestrial – satellite positioning. The principles of U-PN codes generation, as well as the basic methods of their acquisition and tracking, are given too.

    The proposed SC-CDMA principle uses several space distributed sources of radio-signals. The signals are phase modulated by appropriate PN-codes. The Mobile Stations (MS) receive these signals by means of the well known CDMA technology. For this purpose the same PN- codes are generated and synchronized in the MS receiver. The sum(mod2) of these codes creates a new code, which we named U (Unique)- PN code. This code is used for spreading the information, transmitted by the MS. Similar approaches are used for generation of the Base Station (BS) U-PN codes. Proposals of realistic SC-CDMA mobile communication and SC-MRN radar systems, based on the well developed GPS navigation, are shown in the end of the report.

  • «MOMENT» REPRESENTATION OF «FAST DECREASING» GENERALIZED FUNCTIONS AND THEIR APPLICATION TO SEVERAL APPLIED STOCHASTIC PROBLEMS

    pg(s) 21-23

    This paper describes the process of building special space of generalized functions, its properties and applications. Presented applications are: constructive solution of Kolmogorov-Feller type equation with polynomial drift coefficient; proof of exponential nature of equilibrium establishment in rarefied gas, described by Boltzmann equation of kinetic theory of gases.

  • PROCESSING OF INTERFERENCE-CORRUPTED SIGNALS IN CELLULAR RADIO SYSTEMS

    pg(s) 28-30

    Cellular radio communications operate in a severe radio environment. Multipath propagation, inter-channel, inter-symbol and Multiple Access interference, frequency selective fading and many others, contribute to system performance degradation. Contemporary techniques, such as zero-forcing equalization and sophisticated signal filtering, are used for interference cancellation. To observe the system performance, BER analysis is made in this paper.

  • A SURVEY ON THE QUALITY OF DIGITAL IMAGES

    pg(s) 31-33

    The survey of the digital image quality appears to pass through a man’s perception. This leads to a one’s own personal decision. To bring tests on the quality of video information, methods for digital image processing analyses are utilized. Correlation between subjective and objective assessment is explored in this paper. A special video sequences are projected and the subjective influence is compared with a well-founded image quality metrics.

  • Manufacturing schemes of nanoscale structure formation in machine parts

    pg(s) 34-36

    The article considers theuse of manufacturing schemes of thermomechanical processing for production of various machine parts. Schemes of machines for wire and the sized steel introduced on the industrial enterprises are given. Machineswere developed by research teamheaded by Professor Oleg .I. Shavrin at Kalashnikov Izhevsk State Technical University. Comparison of the reached parameters for the developed technologies with basis technologies of thermal processing (typical for the given details) was presented.

  • MODELLING OF PRELOAD DISTRIBUTION IN BOLTED JOINTS WITH THE SPIDER BOLT MODEL

    pg(s) 37-39

    The paper is a part of wider research based on the system approach to the problem of modelling and calculations of bolted flange connections. With this approach it is possible to independent consideration of each system’s element in order to find the best model of this element. The aim of this study is to develop a model of the single-bolted joint separated from the bolted flange connection.
    An analysis is conducted for the spider bolt model which is an equivalent model corresponding to the spatial bolt model. The key problem in the case of modelling bolts with the spider bolt model is adequate distribution of the preload on the bolt head. Accuracy of modelling bolts using the spider bolt model strongly depends on the way of this distribution. The effect of preload distribution in the spider bolt model on stiffness values of the element fastened in the bolted joint has been examined. The result of actions described in the paper is proposal distribution of the preload on nodes belonging to the bolt head which guarantees the best effects of spider bolt model application.

  • PARAMETRIC ANALYSIS OF THE SHIP CAPSIZE PROBLEM

    pg(s) 40-43

    The non-linear ship capsize equation derived by Thompson et al., that incorporates both direct and parametric excitation, is examined numerically in an attempt to deepen our understanding on the influence of the parameters involved in the final ship’s response.
    Because our interest is focused on the binary outcome of capsize-non-capsize, no remark of the steady-state onto which a non-capsize motion may settle is made. The four-dimensional phase-control space includes the non-dimensional damping coefficient, the ratio between wave frequency and ship’s natural frequency, and the direct and parametric forcing amplitudes. All the computed boundaries between capsizing and non-capsizing regions in bi-dimensional projections of control parameter space show fractal features.

  • DEVELOPMENT OF A CAR BODY DESIGNING PROCESS

    pg(s) 43-46

    Car industry is one of the first industries that started using computers in the designing process. A replacement of a conventional designing process has been a long-lasting procedure, especially regarding collaboration. In addition to the necessity for designers’ training and changes in the way of thinking, considerable investments were needed as well. The ambitious goals were not accomplished after all, since the entire process had been conditioned by a large number of participants at various development levels. In this paper, the differences between the conventional designing, designing by computers and virtual designing are presented. A new model was produced, without manufacture of classic prototypes which were replaced by vehicles from the test production. There are the upcoming analyses of the effects, which will certainly influence further development of the designing process.

  • IMPORTANCE OF TRAFFIC SAFETY AND ENVIRONMENTAL PROTECTION IN SERBIA

    pg(s) 47-49

    This paper is devoted to traffic safety and environmental protection in Serbia. Unfortunately the level of air pollution i.e.
    the level of emission of carbon dioxide in the world is still raising. Additional actions are needed in order to limit the effect of climate changes in the following years. People ask why electric vehicles aren’t main-stream? It seems that price has a lot to do with it. The Road Traffic Safety Agency with its systematic and responsible activities set clear guidelines for the monitoring and improvement of road safety in Serbia. In the Republic of Serbia from 1981 till 2013 in the traffic accidents 41.718 persons were killed. In the same period 632.936 persons were seriously injured. Republic of Serbia on the 16th of November 2011 began to commemorate the World’s Day of memory on victims in the traffic accidents. Law on road traffic safety came into effect in the Republic of Serbia in 2009. and brought many changes in our legal order. Majority of those changes meant harmonization with European Union regulation in the area of traffic safety. Changes made by the st new Law on infractions (“Officaial Gazette of the Republic of Serbia“, no. 65/13) in application from March the 1 2014. show the increase of penalties for unscrupulous drivers, but drivers complain on to many regulations and difficulties to get documents for motor vehicle use. In this paper there are mentioned the most efficient hybrids we can buy today. In Serbia “FIAT automobiles of Serbia” is still the leading exporter on the list of 15 biggest Serbian exporters, according to the data of the Serbian Ministry of Finances. In April 2015 at New York Auto Show will be possible to see all new accomplishments in auto-moto industry all over the world.