Goran Janackovic

SELECTION AND RANKING OF OCCUPATIONAL SAFETY INDICATORS BASED ON FUZZY AHP: A CASE STUDY IN ROAD CONSTRUCTION COMPANIES

This paper presents the factors, performance, and indicators of occupational safety, as well as a method to select and rank occupational safety indicators based on the expert evaluation method and the fuzzy analytic hierarchy process (fuzzy AHP). A case study is done on road construction companies in Serbia. The key safety performance indicators for the road construction industry are identified and ranked according to the results of a survey that included experts who assessed occupational safety risks in these companies. The case study confirmed that organisational factors have a dominant effect on the quality of the occupational health and safety management system in Serbian road construction companies.

The selection of the key ergonomic indicators influencing work efficiency in railway control rooms

This paper presents an analytical–synthetic model of ergonomic research of the abilities of the dispatcher/operator in the control room for the automatic control of railway transportation. Twenty performance indicators describing the operators’ performance (work capacity and perceptive abilities) and the main characteristics of the control room (work organization and ergo-technical analysis) are identified. A group fuzzy analytic hierarchy process is applied in the process of ranking and selection of key performance indicators of railway control rooms. The selected key performance indicators (the operator’s hand movement, visual symptoms of fatigue, device error analysis, location and dimensions of the control desk) are analysed in detail.

Multi-Criteria Decision Analysis in Occupational Safety Management Systems

Increasing the effectiveness of occupational safety increases the safety of an organization as its important performance. Safety performance indicators measure changes in the level of safety (related to accident prevention, preparedness and response) over time, which result from the actions taken to reduce appropriate risks. This paper presents the characteristics of basic types of safety indicators, the structure of safety factors, performances and indicators, as well as the multi-criteria decision analysis process and methods in safety management systems.

Multi-criteria decision support for optimal distributed generation dispatch

The problem of optimal dispatch of distributed generation (DG) differs from the classical problem of generation dispatch in the power system, because of the specific criteria related to the DG interconnection. Most important goals are to maximize the renewable production and to minimize the total cost, while satisfying additional constraints related to the operation of a distribution network. When there are many DGs in a distribution network, it is very complicated to decide the optimal DG outputs to satisfy all the criteria and constraints imposed by the distribution network. Another problem is the lack of the dispatcher control over DGs, and very often, the only available action is to switch on or off the generator. Finally, network operator and DG owner perspective is often opposed regarding appropriate control action in the network. In this paper, a multi-criteria decision support based on AHP method is proposed for the choice of the dispatching action. The method is illustrated on the choice of the DG to be switched off in the case or reverse power flow.

The impact of character/background colour combinations and exposition on character legibility and readability on video display units

This paper presents the impact of text and background colour combinations on the legibility of characters and readability of text presented on video display units (VDUs). The stimulus features influencing the operator’s response latency and accuracy are analysed in two experiments, examining the effects of text–background colour combinations and stimulus exposition on the ability of character and word identification on VDUs. This is analysed for the purpose of improving the information presentation in control information systems in Serbian underground coal mines. The legibility of characters based on the main colour combinations was tested by focusing on 30 participants. The first experiment required the participants to identify the legibility of uppercase alphabetic characters and numbers randomly selected and presented on a VDU. The visual performance was expressed by the number of correctly identified characters. The second experiment required the participants to identify the readability of the presented characters, based on the colour combinations of the characters and the background, in order to identify the best possible combination of colours for fast identification of information, which is very important in the detection of fast-changing unwanted events. The results of the experiments suggested that the character recognition was strongly influenced by character/background colour combination and exposition. The adequate selection of these variables can significantly improve the legibility of characters, and improve the speed and the accuracy of the identification of potential problems in underground coal mines during emergency situations.

Development and Application of a Decision Support System for Human Reliability Assessment – A Case Study of an Electric Power Company

This paper describes the human reliability assessment using absolute probability judgment (APJ) method in the Electric Power Company of Serbia (EPS). Taking into account conventional APJ approach, a new decision support tool EPS-APJ was developed. The EPS-APJ tool is intended for use by a group of experts for human error probability assessment. The basic goal of the tool is to facilitate the process of decision-making by experts, in the complex environment of the electric power companies. The usefulness of this new tool is approved in a case study of use of the EPS-APJ for the purpose of the analysis of a repair intervention on a 10/0.4-kV steel lattice tower ‘Nogaje’, in the EPS. For the purpose of this study, a database on work-related injuries, accidents, and critical interventions occurred over a 10-year period was created. The research comprised analysis of 1074 workplaces, with the total of 3997 employees. The case study performed at the EPS has confirmed that the EPS-APJ tool for quantification of human errors is highly applicable, comprehensive, and simple to use. Comparison of the results obtained by application of the EPS-APJ tool versus the basic APJ method has confirmed the accuracy of the decision support tool, and significant speed advantage in conducting an expert evaluation. Copyright

Data Acquisition and Remote Control Systems in Coal Mines: A Serbian Experience

The paper presents the development and application of measurement and control devices and control information systems in coal mines with underground exploitation. The locations of units for measuring the concentration of methane, carbon monoxide and oxygen; the control of short circuits on ventilation doors; the control of main fan depression and the airflow speed are proposed. As a result of the research, the structure of control information system in Senje mine and ergonomic analysis of measurement and control devices in this mine are presented. Further modes of development of control information systems in underground mines in Serbia and solutions for their reconstruction are proposed.

The development of a new integral control model based on the analysis of three complex systems in Serbia

Abstract The aim of this paper is to analyse the results of research carried out in the railway, mining, and electric power systems in Serbia and form a new integral control model. The three methodological procedures are applied. First, analytical-synthetic methodological approach breaks down complex technical system into three parts: bio-cybernetic system, “operator”; technical system, “technology”; and additional system, “working environment.” Second, network planning method is used to analyse time, according to the critical path method. Third, fuzzy analytic hierarchy process determines the key research factors. General results of research are new integral control model, and new research areas and activities. The most prominent factors are: in “bio-cybernetic system”—operator’s arm reach, body postures and movement sequences, operator’s work, occurrence of stress, and occurrence of fatigue; in “technical system”—location and dimension of control desk, display panel, video display terminal, symbols on video display terminal, colours in control centres, and suitability of the keyboards; and in “supporting system”—illumination in control centres and relative humidity. Based on the analysis of factors and synthesis of results, the following recommendation are proposed: new control desk design; new display panel design; new design of the main and local lighting; new illumination and contrast characteristics, and environmental impact assessment. For research on a variety of complex technical systems, new integral control model can be applied, with corresponding extensions.

The key risk indicators of road traffic crashes in Serbia, Niš region

ABSTRACT Traffic crashes are a serious public health and socio-economic problem, and they are one of leading causes of death of males in Serbia. In order to determine the main causes of road traffic crashes in Niš region, Republic of Serbia, nine key risk indicators of road traffic crashes are identified, organized into four groups (number and structure of crashes, consequences of traffic crashes, temporal and spatial location of traffic crashes, causes and sanctions), and described in detail. The indicators are ranked based on group fuzzy analytic hierarchy process (AHP), where experts from insurance companies, professionally engaged in the process of risk assessment, with different previous experience present different impact on the final ranking. In relation to the most influential factors in the assessment of traffic crashes, improper and unadjusted vehicle speed, overtaking and passing, as well as the physical condition of the driver have the highest effect.

Integrative Education Model for Resources and Critical Infrastructure Protection Based on Risk Assessment, Resources Valorization and Threat Ranking

Efficient and effective resource protection from the perspective of society usually involves minimizing costs and capital commitment in any way, while maximizing the percentage of resource utilization. Effective resource management from the perspective of the environment means leaving them in their natural, intact, state. On the other hand, effective and efficient resource protection management activities from the perspective of the army involve efficient resource protection measures during peacetime, emergencies, and even wartime. The aim of this paper is to help develop an adaptive, integrative education model for resource protection, addressing the contemporary needs both within the Ministry of Defence (MoD) and Ministry of environmental protection (MEP) of the Republic of Serbia. The paper offers an in-depth analysis of related core terms: improvement of the current approach to the subject area, nature of the resources that are subject to protection, and different modalities of protection. The applied methodology consists of comparative analysis, statistical methods, and multi-criteria evaluation and assessment. Core determinants (ranking) within the defined model are specified by means of expert judgments method. Obtained results are intended to be used in further implementation processes regarding the developed model.