RFOS - Repository of Faculty of Organizational Sciences Univ. of Belgrade
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Contactless ICT transaction model of the urban transport service
No full textThe paper examines the problem of the productive functioning of an urban passenger transport system, which has a modular structure for the generation and exploitation of the urban transport services. The research objects consist of conventional, scalable and innovative contactless transaction models of an urban transport services in the case study of the Transport Organization (TO) - Joint Stock Company for Passenger Railway Transport "Serbia Trains" (Srbija Voz a.d.). The urban transport service is defined by invoking users, user expectations and requirements, the input data provided by users to a transport provider, the mechanisms for access and delivery of the service, the resources and roles responsible for delivery, security requirements and other parameters. The communication platform for modeling urban transport services in different transaction contexts is defined by the utilitarian framework with 6W dimensions with situational mapping of the 6 Communication Dynamics Factors (6CDF). The technology-process restructuring was achieved with the scalable Information Technology (IT) model by implementing the elements of electronic business in the key activities of the supply of the train tickets. Using the results of the performed research, in the paper has been developed an innovative, non-contact ICT model of urban transport services on the platform for integrating the Internet service into the process-technology and behavioral-context structures
Information Security in M-learning Systems: Challenges and Threats of Using Cookies
No full textThe trend of rapid development of mobile technologies has highlighted new challenges and threats regarding the information security by the using cookies in mobile learning (m-learning) systems. In order to overcome these challenges and threats, this paper has identified two main objectives. First, to give a review of most common types to cookies and second, to consider the challenges and threats regarding cookies with aspects that are directly related to issues of security and privacy. With these objectives is possible to bridge security gaps in m-learning systems. Moreover, the identified potential challenges and threats are discussed with the given proposals of pragmatic solutions for their mitigating or reducing. The findings of this research may help students to rise security awareness and security behavior in m-learning systems, and to better understand on-going security challenges and threats in m-learning systems
Novel Approach to Measuring Business Process Performance
No full textIn the literature, as in practice, there are numerous models for measuring business performance but only a few of them are focused on the business processes, and have integrated process measures with strategic goals, in a way to enable companies to measure progress towards achieving business goals. This paper seeks to address these issues by proposing a new process performance measurement (PPM) model, named GPI model. Model was designed using evidence from the literature, it was tested through multiple case study research, and then it was modified and verified. The GPI model has the potential to become a useful tool for managers in several ways: firstly, the model can be used as a guidance for establishing PPM system that is aligned with strategic goals of company; secondly, the model can be used as it is, with a slight model customization; and thirdly, the universal list of Process performance indicators can be used as a source for best practice
On Fuzzy Solutions to a Class of Fuzzy Multi-objective Linear Optimization Problems
No full textThe class of fuzzy multi-objective linear optimization problems with fuzzy coefficients in the objective functions is addressed in this paper. We introduce a parametric approach that helps to compute the membership values of the extreme points in the fuzzy set solution to such problems. We analyze the efficiency of the feasible basic solutions to a parametric multi-objective linear programming problem through the optimality test in a related linear programming problem. The particular case of triangular fuzzy numbers is presented in detail, and the possible degeneracy of the basic feasible solutions is handled. This paper is a continuation of our work on special classes of fuzzy optimization problems. Previously single-objective (linear and linear fractional) optimization problems with fuzzy coefficients in the objective functions were successfully solved
Probabilized sequent calculus and natural deduction system for classical logic
No full textBy combining, on one side Carnap-Popper-Leblance and Suppes concepts of sentence probability, and Gentzen's sequent calculus LK and natural deduction system NK for classical propositional logic, on the other, we obtain their probabilistic versions. Through an introductory review, we briefly present Gentzen's calculi, Carnap-Popper-Leblance and Suppes probability semantics. Afterwards we introduce systems LKprob, LKprob(e) and NKprob, through axioms and inference rules and define the corresponding probabilistic models followed by examples of derivations in these systems. We define the notion of "probabilized sequent" with the intended meaning that "the probability of truthfulness of is into the interval [a, b]", and in a similar way the notion of "probabilized formula" A[a, b]. The soundness and completeness theorems are proved for all of the presented systems with respect to defined models
CrEx-Wisdom Framework for Fusion of Crowd and Experts in Crowd Voting Environment – Machine Learning Approach
No full textIn recent years crowd-voting and crowd-sourcing systems are attracting increased attention in research and industry. As a part of computational social choice (COMSOC) crowd-voting and crowd-sourcing address important societal problems (e.g. participatory budgeting), but also many industry problems (e.g. sentiment analyses, data labeling, ranking and selection, etc.). Consequently, decisions that are based on aggregation of crowd votes do not guarantee high-quality results. Even more, in many cases majority of crowd voters may not be satisfied with final decisions if votes have high heterogeneity. On the other side in many crowd voting problems and settings it is possible to acquire and formalize knowledge and/or opinions from domain experts. Integration of expert knowledge and “Wisdom of crowd” should lead to high-quality decisions that satisfy crowd opinion. In this research, we address the problem of integration of experts domain knowledge with “Wisdom of crowds” by proposing machine learning based framework that enables ranking and selection of alternatives as well as quantification of quality of crowd votes. This framework enables weighting of crowd votes with respect to expert knowledge and procedures for modeling trade-off between crowd and experts satisfaction with final decisions (ranking or selection)
Post-crisis reputation management – The effect of different crisis communication strategies
No full textIndex Finger Reflection and Smoking
No full textThe reflectance of the index finger on 680 nm was measured. The experimental results show that the intensity of the reflectance for the index finger is related to age and the smoking circumstance. It was shown that reflectance for the index finger nonlinearly increases and reaches the maximum at about 31 - 32 age for nonsmoker age. Index finger reflectance between smoker and nonsmoker was compared. It was observed that smokers’ index finger reflectance is significantly greater compared with the index finger reflectance for nonsmokers
