Andrej Škraba

Simulation Approach to Decision Assessment in Enterprises

The methodology of an integrated simulation system application for decision-making support in enterprises is described in this article. The use of visual interac tive modelling and animation can help users better understand simulation results, especially those who are not experts. Decision-makers are motivated by the aniniation while seeking better solutions for pro duction problems. The method was tested in a medium- sized company in order to improve operational plan ning and re-engineering. The real process was recorded on video, digitized, and implemented on a PC. Anima tion of the simulated process, synchronized with video of the real process, was projected in a room to achieve model validation and participant confidence. Opera tional production plans were simulated using current demands as the basis. Application of discrete event simulation in reengineering is also presented. The article shows how to develop a model, prepare sce narios and evaluate alternatives. Two criteria were evaluated for the alternative: the expected value and the value of multiple criteria evaluation, which was examined with the AHP method. Model validation and its use for alternative selection is also discussed.

Speech-controlled cloud-based wheelchair platform for disabled persons

This paper describes the development of the prototype speech controlled cloud based wheelchair platform. The control of the platform is implemented using low-cost available speech WebKit in the cloud. Besides the voice control, the GUI is implemented which works in the web browser as well as on the mobile devices providing live video stream. The platform is based on Mini PC running Ubuntu Linux and Arduino UNO Microcontroller. Software development was done in JavaScript / ECMA Script.

Prototype of speech controlled cloud based wheelchair platform for disabled persons

This paper describes the development of the prototype speech controlled cloud based wheelchair platform. The control of the platform is implemented using low-cost available speech WebKit in the cloud. Besides the voice control, the GUI is implemented which works in the web browser as well as on the mobile devices providing live video stream. The platform is based on Mini PC running Ubuntu Linux and Arduino UNO Microcontroller. Software development was done in JavaScript / ECMA Script.

The System Dynamics Model for Development of Organic Agriculture

Organic agriculture is the highest environmentally valuable agricultural system, and has strategic importance at national level that goes beyond the interests of agricultural sector. In this paper we address development of organic farming simulation model based on a system dynamics methodology (SD). The system incorporates relevant variables, which affect the development of the organic farming. The group decision support system (GDSS) was used in order to identify most relevant variables for construction of causal loop diagram and further model development. The model seeks answers to strategic questions related to the level of organically utilized area, levels of production and crop selection in a long term dynamic context and will be used for simulation of different policy scenarios for organic farming and their impact on economic and environmental parameters of organic production at an aggregate level.

Determination of recruitment and transition strategies

Purpose – This paper aims to describe the development and application of a manpower planning system for the Slovenian armed forces using a system approach, system dynamics (SD) and numerical optimization.Design/methodology/approach – The model of the hierarchical manpower system was developed by SD methodology and formulated in discrete time space. The problem of tracking the goal trajectories in the eight topmost ranks at the prescribed boundaries was solved by application of the quadratic performance index and finite automata (FA) which was used for classification of acceptable strategies. Genetic algorithms (GA) as well as pattern search were compared at the numeric optimization.Findings – Employing SD and a system approach increases the understanding of the system control. The definition of an optimum strategy, which would consider only target values for ranks within prescribed parameter boundaries, could provide an undesired oscillatory solution. Inclusion of rules by FA to determine acceptable strat...

Streaming pulse data to the cloud with bluetooth LE or NODEMCU ESP8266

The paper describes the development of the three prototypes which enable monitoring of heart pulse sensor data on the cloud. The prototypes are based on a) Bluetooth module, b) Low Energy Bluetooth module and c) ESP8266 Wi-Fi module. The client side implementation is developed by the application of JavaScript. Node.js was used on the server side with application of node-serialport library with Bluetooth modules. In the case where ESP8266 Wi-Fi module was used, the data was transmitted directly to the cloud. The three different prototypes were compared according to the power consumption and complexity of design. The code example is provided illustrating the approach to develop cloud based graphing interface for biomedical mobile monitoring.

Wheelchair maneuvering using leap motion controller and cloud based speech control: Prototype realization

The paper describes the development of prototype wheelchair platform controlled by the gestures. Leap Motion Controller is used to acquire data while changing the hand position. The novel user interface was developed, which shows the hand position to the user and combines the classical button GUI switchboard. The developed system is cloud based and integrates speech recognition to engage the motion controller as well as to control the entire platform if needed. The entire software was developed with JavaScript/ECMA Script.

The Development of Sugar Beet Production and Processing Simulation Model – a System Dynamics Approach to Support Decision-Making Processes

Abstract Background: The sugar beet is the main field crop used for sugar production in the temperate climatic zone. The abolishment of the quota system will open new investment opportunities in countries that were forced to abandon sugar industry as the result of the reform in 2006. Present paper describes the modeling of sugar beet production and its processing into sugar for purpose of decision support. Methods: A system dynamics methodology was chosen to model impacts of regional sugar factory investment. We present two basic concepts of system dynamics models at causal loop diagram level. The first holistic model deals with regional planning of new product development and the second one deals with factory model. Results: The holistic model presented main feedback loops and dynamics of main elements in the case of regional investment into sugar industry. The factory model considered the specifics of the beet processing which is a) limited period of beet processing and b) initial adjustment to the production capacity at the start of the production season Conclusions: The model seeks answers to strategic questions related to the whole sugar beet production and processing system and will be used for simulation of different scenarios for sugar production and their impact on economic and environmental parameters at an aggregate level.

System dynamics model for policy scenarios of organic farming development

This paper presents the system dynamics model of organic farming development in order to support decision making. The model seeks answers to strategic questions related to the level of organically utilized area, levels of production and crop selection in a long-term dynamic context. The model will be used for simulation of different policy scenarios for organic farming and their impact on economic and environmental parameters of organic production at an aggregate level. Using the model, several policy scenarios were performed.

Adaptive fuzzy inventory control algorithm for replenishment process optimization in an uncertain environment

This paper presents a real case study of warehouse replenishment process optimization on a selected sample of representative materials. Optimization is performed with simulation model supported by inventory control algorithms. The adaptive fuzzy inventory control algorithm based on fuzzy stock-outs, highest stock level and total cost is introduced. The algorithm is tested and compared to the simulation results of the actual warehouse process and classic inventory control algorithms such as Least-unit cost, Part period balancing and Silver-Meal algorithm. The algorithms are tested on historic data and assessed using the Fuzzy Strategy Assessor (FSA). Simulation results are presented and advantages of fuzzy inventory control algorithm are discussed.