Analysis of the influence of car-following input parameters on the modelled travelling timeIrena Ištoka Otković
, Tomaž Tollazzi
, Matjaž Šraml
, 2013, kratki znanstveni prispevek
Opis: The calibration process is a basic condition of traffic model application in local conditions. The choice of input parameters, which are used in calibration process, influences the success of the calibration process itself; therefore, the goal is to choose parameters with a larger influence on the modelling process. This paper offers a detailed analysis of car-following input parameters and their influence on the modelled travelling time. The experimental basis was a one-lane roundabout, and the tool used for traffic simulation was the VISSIM microsimulation traffic model. The results show that the car-following input parameters should be a part of the set of input parameters, which will enter the process of calibration. The examined car-following input parameters affect the capacity of intersections and results show that it is necessary to revise the range of input values of one of the observed car-following input parameters.
Ključne besede: car-following input parameters, input parameters for the process of calibration, VISSIM
Objavljeno: 11.07.2017; Ogledov: 73; Prenosov: 6
Celotno besedilo (680,10 KB)
Determinants of cruise passengers' expenditures in the port of callMaršenka Marksel
, Polona Tominc
, Stanislav Božičnik
, 2016, izvirni znanstveni članek
Opis: Cruise tourism generates different types of cruise consumption and related indirect, direct and induced expenditure effects, in homeports as well as in ports of call. Cruise passengers´ expenditures produce positive economic effects for destinations, from increasing the incomes and employment, to tax incomes, duties, etc. Therefore, it is no doubt that cruise stakeholders and local economies can benefit from increased cruise passenger consumption. To stimulate higher consumption and passengers´ satisfaction, it is necessary to design the supportive policy framework and build appropriate quality of products and services. Identifying influential variables of cruise passengers´ expenditures in this sense enables the design of appropriate policies and measures. In the current research, based on a survey of 357 cruise passengers, several variables included in a new theoretical model of the expenditures determinants, such as gender, nationality, frequency of cruising and frequency of visits, were found to be statistically significantly associated with cruise passengers´ expenditures. Several conclusions and suggestions to stimulate cruise passenger expenditures based on research findings are provided.
Ključne besede: cruise tourism, consumption, behavioural intentions, tourism, maritime transport
Objavljeno: 04.07.2017; Ogledov: 48; Prenosov: 2
Celotno besedilo (773,65 KB)
Isospin violating decays of positive parity Bs mesons in HMχPTSvjetlana Fajfer
, Anita Prapotnik Brdnik
, 2016, izvirni znanstveni članek
Opis: Recent lattice QCD results suggest that the masses of the first two positive parity Bs mesons lie below the BK threshold, similar to the case of D∗s0(2317)+ and Ds1(2460)+ mesons. The mass spectrum of Bs mesons seems to follow the pattern of a Ds mass spectrum. As in the case of charmed mesons, the structure of positive parity Bs mesons is very intriguing. To shed more light on this issue, we investigate the strong isospin violating decays B∗0s0→B0sπ0, B0s1→B∗0sπ0, and B0s1→B0sππ within heavy meson chiral perturbation theory. The two-body decay amplitude arises at tree level and we show that the loop corrections give significant contributions. On the other hand, in the case of three-body decay B0s1→B0sππ the amplitude occurs only at loop level. We find that the decay widths for these decays are Γ(B0s1→B0sππ)∼10−3 keV, and Γ(B∗0s0→B0sπ0)≤55 keV, Γ(B0s1→B∗0sπ0)≤50 keV. More precise knowledge of the coupling constant describing the interaction of positive and negative parity heavy mesons with light pseudo-scalar mesons would help to increase the accuracy of our calculation.
Ključne besede: physics, elementary particles, B mesons, decays
Objavljeno: 26.06.2017; Ogledov: 92; Prenosov: 2
Celotno besedilo (743,71 KB)
Open space evaluation methodology and three dimensional evaluation model as a base for sustainable development trackingMelita Rozman Cafuta
, 2015, izvirni znanstveni članek
Opis: Sustainable development, as a concept of controlled development, is a management characteristic. Adaptation to progress is important to achieve sustainability. The research focus here is on developing an evaluation methodology for determining the characteristics of urban open space. A method was designed for use in the comparative analysis of environmental perception evaluation between different time sequences. It allows us to compare results before and after spatial interventions or spatial development tracking over time. The newly-developed SEC model (suitable for everyone, environmentally-accepted, and cost-effective) was an essential element used in the research methodology. The model was designed using the systematic principle, the top–down approach, and the decomposition method. Three basic dimensions were divided into six factors. Factors were divided into eighteen indicators that are either quantitatively or qualitatively assessed. Indicators were divided into several aspects. An instrument (questionnaire) was developed to support the evaluation methodology of urban open space characteristics. Every aspect belongs to a question in the questionnaire. The applicability of the SEC model was demonstrated in two case studies. Evaluation took place during two different time sequences, once during the day-time and once during the night. Obtained results provide useful information of the current spatial situation needed for sustainable development strategy preparation.
Ključne besede: urbano okolje, vizualna percepcija, vizualno zaznavanje, vidno zaznavanje, metodologija vrednotenja, SEC model
Objavljeno: 22.06.2017; Ogledov: 109; Prenosov: 4
Celotno besedilo (2,65 MB)
On algebraic approach in quadratic systemsMatej Mencinger
, 2011, pregledni znanstveni članek
Opis: When considering friction or resistance, many physical processes are mathematically simulated by quadratic systems of ODEs or discrete quadratic dynamical systems. Probably the most important problem when such systems are applied in engineering is the stability of critical points and (non)chaotic dynamics. In this paper we consider homogeneous quadratic systems via the so-called Markus approach. We use the one-to-one correspondence between homogeneous quadratic dynamical systems and algebra which was originally introduced by Markus in (1960). We resume some connections between the dynamics of the quadratic systems and (algebraic) properties of the corresponding algebras. We consider some general connections and the influence of power-associativity in the corresponding quadratic system.
Ključne besede: quadratic systems, nonlinear systems
Objavljeno: 14.06.2017; Ogledov: 169; Prenosov: 3
Celotno besedilo (2,74 MB)
An application of the Sakai's theorem to the characterization of H*-algebrasBorut Zalar
, 1995, izvirni znanstveni članek
Opis: The well-known Sakai's theorem, which states that every derivation acting on a von Neumann algebra is inner, is used to obtain a new elegant proof of the Saworotnow's characterization theorem for associative ▫$H^\ast$▫-algebras via two-sided ▫$H^\ast$▫-algebras. This proof completely avoids structure theory.
Ključne besede: mathematics, functional analysis, ▫$H^\ast$▫-algebra, involution, automorphism, derivation, centralizer, von Neumann algebra
Objavljeno: 14.06.2017; Ogledov: 59; Prenosov: 3
Celotno besedilo (2,06 MB)
Traffic safety of older drivers in various types of road intersectionsTomaž Tollazzi
, Marko Renčelj
, Vlasta Rodošek
, Borut Zalar
, 2010, pregledni znanstveni članek
Opis: In industrialized countries people over 50 years of age represent a rapidly growing part of population. Their lifestyle is also becoming more active, which means that the percentage of older drivers in the population of all drivers is also increasing. Many different studies have shown that elderly drivers are more frequently involved in specific types of accidents, especially at intersections.
In the past 15 years there was a trend of increasing popularity of roundabouts in Slovenia. Their introduction was generally supported by the arguments of increased traffic-flow capacity and traffic safety as well. The studies on which these arguments are based were performed with an “ideal” type of driver in mind; the one that fully understands new rules and reacts correctly in all situations that may occur at such intersections, where there are no light signals to guide them. An elderly person does not necessarily conform to that ideal and if the percentage of elderly drivers became significant, the premises of the above mentioned studies may not be correct anymore which in turn implies that their results could also be questioned.
The present study concentrated on the evaluation of traffic safety of elderly drivers, at various types of intersection, from their own perspective. Various statistical analyses of obtained data were performed. The most important finding was that we may claim, with high degree of probability, that the average person of the age of over 60 feels more unsafe at double-lane roundabouts than they would feel had the same intersection been equipped with traffic lights.
Elderly traffic participants will always cause more accidents or participate in them due to hazardous factors. Challenge, arising from many different studies and researches, is in studying what measures and solutions can reduce the risk for elderly participants.
Ključne besede: traffic safety, road intersections, roundabouts, elderly people
Objavljeno: 06.06.2017; Ogledov: 104; Prenosov: 9
Celotno besedilo (811,32 KB)
Theoretical model for determination of airspace capacityBranko Lučovnik
, Martin Lipičnik
, Domenik Lebar
, Janko Blatnik
, 2002, pregledni znanstveni članek
Opis: In the last decade, the constant air traffic growth has brought certain problems as well. While aircraft production and airline functioning are being stimulated by the competition, the situation in air traffic control and in infrastructure component is completely different. Air traffic management (ATM) is still owned by the state. The state, however, is known for the fact of not being a good manager and is solving problems slowly and not efficiently because of its large administration. There is a very strong trade union movement functioning in ATM system, which makes several rational decisions impossible. Critics of the current ATM system in Europe warn of increasing problems-delays and operational expenses. The control component is the only one among the four components of air traffic, which has not been liberalised and harmonised yet. There is no competition in the fields of air traffic. All matters are taken care of by CAA or by semi-private companies, owned by the state. According to air carriers which have to put in 4-9% of business expenses into terminal-and over-flights charges, these expenses are far too heavy a burden.
Ključne besede: air traffic, airspace capacity
Objavljeno: 06.06.2017; Ogledov: 110; Prenosov: 2
Celotno besedilo (3,30 MB)
The impact of regulation 561/2006 on fleet management viewed through efficient use of drivers' working timeRobert Muha
, Drago Sever
, 2009, pregledni znanstveni članek
Opis: The introduction of contemporary procedures to fleet management processes has recently changed the work planning and supervision of driver's work activities. Tendencies to control the implementation of driver's work have been present in modem professional practice for quite a long time; however, the equipment available on the market limited its implementation. The intensified development of digital tachographs has, in technical terms, ensured such equipment considerably before the legislative groundwork was prepared for its practical implementation. The Commission Regulation (EC) No. 561/2006 (implementation of Social legislation relating to Road Transport) does not bring any essential novelties in terms of permitted workload. Consistent monitoring of drivers activities, made possible by digital tachographs, will have impact on the existing working methods. The topic of the present paper is in deep analysis of the impact of the mentioned regulation with special emphasis on the conditions for the regulation of the current stage of drivers work and on the expected consequences. The essential importance lies on the expected change in the mentality and approach to planning the driver's activities in the transport process on the part of the carrier: the outcome will eventually result in the efficiency of each individual carrier.
Ključne besede: fleet management, driver's work planning, digital tachographs
Objavljeno: 06.06.2017; Ogledov: 53; Prenosov: 5
Celotno besedilo (2,98 MB)