The contribution of cng powered vehicles in the transition to zero emission mobility example of the light commercial vehicles fleet

The aim of paper was to discuss contribution of bi-fuel CNG powered light commercial vehicles to the well-to-wheel CO2 equivalent emissions, both today and in the coming decades in which the development of new fuels and new vehicles is expected. Field research was done in Belgrade, during one year, using Euro 5 diesel/LPG/CNG light commercial vehicles driving under low vehicle speed, low engine load, low exhaust gas temperature and high number of stops. The well-to-wheel as neutral methodology was applied for understanding of each fuel pathway in terms of reducing greenhouse gas emissions and increasing energy efficiency. Calculation showed that total energy consumption per kilometre is the lowest for diesel vehicles since petrol/LPG and petrol/CNG vehicles use 21% and 7% more energy. Tank-to-wheel emission of CO2 equivalent is most favorable for petrol/CNG with 28.8% and 6.7% less CO2 equivalent with petrol/LPG and diesel vehicles. The same conclusion brings well-to-wheel analysis showing that diesel/CNG CO2 equivalent emission is 13.5% less than petrol/LPG, apropos 1.5% less than diesel operated vehicles considered within this field research. Figures are not as high as previous, due to the results of well-to-tank emission, that were most favorable for petrol/LPG powered vehicles, with almost 51% and 32% better results regarding to petrol/CNG and diesel, respectively. Within same time, lowest fuel cost per kilometre was achieved by petrol/CNG vehicles, with 32% and 35% less cost than petrol/LPG and diesel vehicles. The available CNG technology should not be neglected, waiting for new solutions to be proven

PERFORMANCE ASSESSMENT OF THE BALKAN COUNTRIES IN THE INFORMATION AND COMMUNICATION TECHNOLOGIES SECTOR

The rapid technological development of the last decades has affected practically all areas of the economy, society, and culture. Almost every aspect of life and work in the modern world to a greater or lesser extent depend on the use of information and communication technologies (ICT). The aim of this paper is to analize the ICT performance of ten Balkan countries and to highlight areas that need further improvement. The analysis is based on the data published by the International Telecommunication Union in annual Measuring the Information Society Report. The research is conducted through comparative analysis and benchmarking method. The ten best-positioned European countries in terms of ICT development represent the benchmark group. The analysis finds low level of national ICT performance of the Balkan countries compared to the selected European countries. The conclusions of this research may serve as guidelines for ICT policy makers in the observed economies

The contribution of cng powered vehicles in the transition to zero emission mobility example of the light commercial vehicles fleet

The aim of paper was to discuss contribution of bi-fuel CNG powered light commercial vehicles to the well-to-wheel CO2 equivalent emissions, both today and in the coming decades in which the development of new fuels and new vehicles is expected. Field research was done in Belgrade, during one year, using Euro 5 diesel/LPG/CNG light commercial vehicles driving under low vehicle speed, low engine load, low exhaust gas temperature and high number of stops. The well-to-wheel as neutral methodology was applied for understanding of each fuel pathway in terms of reducing greenhouse gas emissions and increasing energy efficiency. Calculation showed that total energy consumption per kilometre is the lowest for diesel vehicles since petrol/LPG and petrol/CNG vehicles use 21% and 7% more energy. Tank-to-wheel emission of CO2 equivalent is most favorable for petrol/CNG with 28.8% and 6.7% less CO2 equivalent with petrol/LPG and diesel vehicles. The same conclusion brings well-to-wheel analysis showing that diesel/CNG CO2 equivalent emission is 13.5% less than petrol/LPG, apropos 1.5% less than diesel operated vehicles considered within this field research. Figures are not as high as previous, due to the results of well-to-tank emission, that were most favorable for petrol/LPG powered vehicles, with almost 51% and 32% better results regarding to petrol/CNG and diesel, respectively. Within same time, lowest fuel cost per kilometre was achieved by petrol/CNG vehicles, with 32% and 35% less cost than petrol/LPG and diesel vehicles. The available CNG technology should not be neglected, waiting for new solutions to be proven

Simulation of the transmission by vectors of bluetongue disease and analysis of the control strategy

Bluetongue disease is an infectious non-contagious disease of domestic and wild ruminants, transmitted by hematophagous insects of the genus Culicoides. In endemic areas the disease has a seasonal character, occurs usually in summer when the population of vectors is at its peak. Culicoides are active at temperatures in the range from 13 degrees to 35 degrees C. The replication of the virus stops when the environmental temperature is below 13 degrees C. It has been reported that the temperature and humidity of the environment affect to a great extent the biology of the vector and the survival of the virus in the reservoirs. During the summer, the number of infected cattle and sheep is directly dependent on the density of the population of the vector, the length of vectors life-span, the temperature of the environment and by precipitation, the affinity of the vector to different hosts, and the ability of the vector to locate the host. Bluetongue has been spreading worldwide due to climatic changes and increasing average daily temperatures. The seasonal occurrences of the disease and the climate change have conditioned the need for adopting new strategies. The stochastic SEIRD mathematical model has been developed in order to simulate the transmission of the Bluetongue virus through the susceptible ruminant population on the territory of the Republic of Serbia, as well as to investigate the effect of climatic factors on the vector population and the magnitude of a possible epizootia. Besides the effects of climatic factors, we have analyzed a number of different approaches in the control of the disease based upon the vaccination of ruminants and control of vectors

Damage mechanism and barrier identification on hydrogen production unit using innovative methodology for risk assessment

In the oil and gas industry hydrogen is used in a large number of processes, mostly in hydroprocessing units such as hydrotreating, hydrocracking and other refining processes that increase the hydrogen-to-carbon ratio. To satisfy the need for H-2, refineries usually have a dedicated Hydrogen Production Unit (HPU). Given the wide range of processes that HPU supplies and the fact that cost of operation of this kind of unit is rather high, it stands to reason that any kind of interruption in unit operation will affect the whole refining process. From Risk Based Inspection (RBI) point of view, HPU can be a very challenging unit to deal with, primarily due to the wide range of operating processes conditions as well as different operating fluids. As a result of applying the innovative methodology for risk assessment, it is shown that significantly higher number of damage mechanisms are identified in regard to the number of damage mechanisms that would be identified by applying traditional methodology, due to the fact that both active and passive damage mechanisms are identified. Concept of barriers such as measures that are able to restrict, reduce or preferably eliminate damage mechanisms identified in HPU are introduced and discussed. Innovative methodology was successfully applied in the case of a refinery in the Middle East

Social networks: Networks of old school ties

U tekstu se ispituje primenljivost pojma mreža školskih drugara u analizi umreženosti poslovne elite u Srbiji. Na podacima empirijskog istraživanja sprovedenog 2012. godine na uzorku ekonomske elite pokazuje se da ima osnova za prihvatanje hipoteze prema kojoj lični uspeh zavisi od homogenosti grupacije kojoj uspešni pojedinci pripadaju, ali da ta homogenost može proisticati iz više izvora, a mreža školskih drugara predstavlja samo jedan od tih izvora.In this article we examine if the term 'old school ties' is applicable in analyzing of Serbian business elite networking. The starting assumption is that business success depends on the level of sociocultural homogeneity of a group of successful individuals. Data from an empirical research conducted in 2012 on a sample of economic elite, showed that such assumption was grounded, but that the group homogeneity could originate from different sources. The first source is primary socio-cultural milieu which includes peer similarities, growing up in similar family environments and attending the same schools. This milieu is the closest to the term 'old school ties' in its usual meaning. Beside these, there are various kinds of secondary milieus, some of the most important ones being the class habitat. This research shows that class affiliation and profession, in particular, have the biggest impact on forming of networks that contribute to business success. The results also show that there are significant differences between members of business elite and lower social layers in relation to this issue. The lower a social layer is on the social ladder, the more important home origin becomes. Today, nationality and religious affiliation are not that important for creation of business networks

Sociological issues in the first decade of 21st century: Comparative analysis of Serbia and Croatia

U tekstu se analizira tematska usmerenost socioloških radova objavljenih u tri sociološka časopisa u Srbiji i Hrvatskoj (Sociologija, Sociološki pregled i Revija za sociologiju) tokom dve poslednje decenije XX i prve decenije XXI veka. Cilj teksta je da ustanovi kojim temama su se sociolozi u Srbiji bavili tokom ovog burnog istorijskog perioda i da se na osnovu toga odgovori na pitanja da li i u kojoj meri je srpska sociologija pratila društvene promene, odnosno u kojoj meri je bila pod njihovim uticajem. U drugom delu teksta analizira se otvorenost srpske sociologije prema svetu u svetlu navedenih promena. Da bi ocene i zaključci o pomenutim promenama bili što odmereniji posmatrani su u uporednom okviru sa stanjem u hrvatskoj sociologiji.The paper analyzes the thematic orientation of sociological works published in three sociological journals in Serbia and Croatia (Sociologija, Sociološki pregled and Revija za sociologiju) during two last decades of 20th and the first decade of 21st century. The aim of the paper, set in the opening section, is to investigate the topics which are dealt with by sociologists in Serbia during this turbulent historical period. On the basis of this analysis, answers to the following questions will be attempted: has Serbian sociology kept track, and to what extent, of the changes taking place in the society, and hence how much it has been under the influence of the latter. In the second part of the article the openness of the Serbian sociology toward the world is discussed in the context of aforementioned changes. In order to make judgments and conclusions as objective as possible this topic is considered in a comparative framework - comparing it with conditions in Croatian sociology

Kardiorespiratorni fitnes i njegov značaj u reakcijama kortizola i laktata prilikom zimskih i letnjih marševa

Background: The influence of homeostatically regulated physiological processes, including cardiorespiratory fitness (VO2max), on the response to physical stressors such as acclimatisation and marching, remains understudied. We aimed to investigate the effects of summer and winter acclimatisation and marching on cortisol levels and blood lactate, to gain insight into the role of these physiological processes in the stress response. Methods: Two groups of young Europeans, classified as poor (PCF; n=9) and good physical condition (GCF; n=21), based on a VO2max threshold of 40 mL O2/ kg/min, underwent 2-h march (6–7 km/h) in winter (5 ∘C) and summer (32 ∘C). Commercial tests, UniCel DxI Access Cortisol assay and EKF Biosen Clinic/GP assay were used for cortisol and lactate blood measurements (morning samples and those taken immediately after marches), respectively. Results: Basal cortisol levels were significantly higher at 5 °C than at 32 °C (PCF group: P=0.0079; cortisol dropped after the march at 5 °C in both groups, but increased at 32 °C only in PCF. Basal lactate levels were higher at 32 °C only in the GCF group (compared to PCF, P=0.0014) and post-marching (compared to basal values, P=0.0002). Conclusion: Cold exposure elicits a more significant stress response, based on higher basal cortisol levels, in individuals with worse physical fitness. Anaerobe metabolism prevails in participants with better physical fitness exposed to high ambient temperature based on increased basal and post-marching lactate levels. The study is significant for individual training/performance optimisation as it indicates the association between physiological stress responses and individual physical fitness levels.Uvod: Uticaj homeostatski regulisanih fiziolo{kih procesa, uklju~uju}i kardiorespiratornu kondiciju (VO2max), na odgovor na fizi~ke stresore poput aklimatizacije i mar{i- ranja, ostaje nedovoljno prou~en. Cilj istra`ivanja je bio i da se ispita uticaj aklimatizacije i mar{iranja tokom leta i zime na nivoe kortizola i laktoze u krvi, pru`aju}i uvid u ulogu ovih fiziolo{kih procesa u odgovoru na stres. Metode: Dve grupe mladih Evropljana, klasifikovane kao osobe sa slabom (PCF; n=9) i dobrom fizi~kom kondicijom (GCF; n=21), na osnovu praga VO2max od 40 mL O 2/kg/min, su bile izlo`ene dvosatnom mar{u (6–7 km/h) u dva navrata, zimi na 5 °C i leti, na 32 °C. U uzorcima krvi (jutarnji i neposredno nakon mar{a) su odre|ivani nivoi kortizola i laktata komercijalnim testovima, UniCel DxI Access Cortisol i EKF Biosen Clinic/GP. Rezultati: Bazalni nivoi kortizola su bili zna~ajno vi{i na 5 °C nego na 32 °C (u PCF grupi: P=0,0079); nakon mar{i- ranja na 5 °C kortizol opada u obe grupe a pove}an je na 32 °C samo u PCF grupi. Bazalni nivoi laktoze bili su vi{i na 32 °C samo u GCF grupi (porede}i sa PCF grupom, P=0,0014) i nakon mar{iranja (porede}i sa bazalnim vred- nostima, P=0,0002)

Application of innovative risk assessment methodology for damage mechanisms identification on part of amine regeneration unit

When implementing the method for quantitative risk analysis, usually based on RBI (Risk Based Inspection), conditions which directly influence the identification of damage mechanisms are defined at the beginning of the analysis. Thus, conducted analysis applies to the exact parameters and very specific combinations of conditions and damage mechanisms. The question arises as to whether such an analysis and its results may represent initial data for some subsequent analysis that can be carried out in the following period, regardless of the reasons for the implementation. The extension of the methodology from the one shown in the ASME PCC 3 standard is to identify both active and passive/potential damage mechanisms and the conditions under which passive can be activated. This addition to the methodology is successfully applied in case of a Middle East refinery, and as a representative example, a typical amine regeneration unit present in all modern gas or oil refineries, specifically the part of the unit with lean amine, is shown

Excitatory amino acid b-N-methylamino-L-alanine is a putative environmental neurotoxin

The amino acid b-N-methylamino-L-alanine (L-BMAA) has been associated with the amyotrophic lateral sclerosis/parkinsonism-dementia complex in three distinct western Pacific populations. The putative neurotoxin is produced by cyanobacteria, which live symbiotically in the roots of cycad trees. L-BMAA was thought to be a threat only to those few populations whose diet and medicines rely heavily on cycad seeds. However, the recent discovery that cyanobacteria from diverse terrestrial, freshwater, and saltwater ecosystems around the world produce the toxin requires a reassessment of whether it poses a larger health threat. Therefore, it is proposed that monitoring L-BMAA levels in cyanobacteria-contaminated water supplies might be prudent