Zeljko Hocenski

• J.J. Strossmayer University of Osijek

Dynamic voltage and frequency scaling (DVFS) is a technique used to optimize energy consumption in ultra-low-power embedded systems. To ensure sufficient computational capacity, the system must scale up its performance settings. The objective is to conserve energy in times of reduced computational demand and/or when battery power is used. Fast Four...

The ceramic tiles industry has a significant environmental impact due to consumption of raw materials, energy and environmental emissions. There are numerous activities on global level in accordance to the principles of sustainable development. This paper presents the development and application of mathematical models of manufacturing processes bas...

Increased use of energy in buildings and HVAC systems requires advanced control schemes like model-based control to improve energy efficiency, which in turn requires accurate thermodynamic models of buildings. The Resistive-Capacitive (RC) method is a popular and versatile approach for thermal modeling of buildings. Despite this, it is not easy to...

Automated defect detection is difficult to achieve in ceramic tile manufacturing today. Computer vision and machine learning based approaches are commonly utilised for this purpose. This paper considers the problem of defect detection in the textured ceramic tiles quality analysis. Instead of detecting defects on the finished tile, the biscuit tile...

In this paper, we present a concept of the smart sticker for the use in product storage and transportation, the main elements of the supply chain. Complete automation of the supply chain elements was the goal since the rapid development of information technologies. Our concept proposes data logging of the product environment conditions during stora...

Clustering of uncertain objects in large uncertain databases and problem of mining uncertain data has been well studied. In this paper, clustering of uncertain objects with location uncertainty is studied. Moving objects, like mobile devices, report their locations periodically, thus their locations are uncertain and best described by a probability...

In this paper we propose a novel real-time Biscuit Tile Segmentation (BTS) method for images from ceramic tile production line. BTS method is based on signal change detection and contour tracing with a main goal of separating tile pixels from background in images captured on the production line. Usually, human operators are visually inspecting and...

In this work a wireless sensor network is presented realized by 8-bit microcontrollers and NRF24L01 RF communication modules. Network is working by master- slave communication principle. The system takes input data from several slave devices, with a DHT11 temperature and humidity sensor. Multiple sensor data is collected on the master device. After...

Preliminary results of the Computer Vision Station Prototype for Biscuit Tiles Quality Control.

Visual inspection is carried out manually in ceramic tile industry in Croatia using specially trained and skilled workers. Currently in industry biscuit and crude tiles are not visually inspected for defects. Fatigue, illness and other subjective factors significantly influence workers percentage of found defects and classification quality. In this...

Energy efficiency is becoming more important issue, especially in buildings sector where 15–20% of total energy in developed countries is used. One course toward higher efficiency is to improve HVAC (Heating, Ventilation and Air Conditioning) systems in building, especially by implementation of advanced control methods. Efficiency of these control...

This paper presents a new efficient method for crop row detection which uses a dynamic programming technique to combine image evidence and prior knowledge about the geometric structure which is searched for in the image. The proposed approach consists of three steps, i.e., (i) vegetation detection, (ii) detection of regular patterns, and (iii) dete...

U radu se opisuje praćenje i snimanje značajki vožnje radi istraživanja utjecaja različitih načina vožnje na potrošnju automobila. Kao glavna značajka vožnje odabran je broj okretaja motora. Pri istraživanju u različitim načinima vožnje poštovana su prometna ograničenja. Na temelju snimljenih podataka izvršena je analiza načina vožnje. Pokazano je...

Making buildings more energy efficient while keeping thermal comfort has been an important topic in last decades, including improving efficiency of Heating, Ventilation and Air Conditioning (HVAC) systems. One approach to this goal is to use better control methods. This paper presents a review of methods which have been researched in scientific pap...

This article presents a method for detecting changes in behavior of data. It is based on cluster analysis, which is a common name for methods that group data in segments called clusters, based on similarities and differences of data itself, without supervision of human observer. The data analyzed by clustering techniques are commonly met in process...

This paper proposes a simulation environment for creating simulated ranging data of high resolution sonar systems. It enables the assessment of underwater object reconstruction techniques and the verification of various methods for automated target detection. As an input, the proposed environment uses the AUV's trajectory, a model of the sonar syst...

This paper addresses adjustments, implementation and performance comparison of the Moving Average with Local Difference (MALD) method for ceramic tile surface defects detection. Ceramic tile production process is completely autonomous, except the final stage where human eye is required for defects detection. Recent computational platform developmen...

In attempts to increase the production quality and to decrease the production costs in ceramic tile industry almost every phase in the production process needs to be automated. One way of decreasing the production costs is to detect the tiles with defects before the baking process (biscuit tiles). The separated tiles are returned to the input mater...

With the rising trend of oil prices the need to reduce fuel consumption in commercial vehicles is becoming even more emphasized. As gasoline prices have been literally tripled in the past few years fuel efficiency is becoming increasingly important. This presents a problem for older and non OBD-II compliant petrol vehicles, as one prerequisite for...

This paper describes the FPGA based verification platform that is dedicated to improve student efficiency for the course on Digital Design with FPGAs. We developed a functional verification platform that extends the number of I/O devices, which is usually limited on development kits. Simple PicoBlaze CPU-based design is used to synchronize the inpu...

There exist many problems regarding process control in the process industry since some of the important variables cannot be measured online. This problem can be significantly solved by estimating these difficult-to-measure process variables. In doing so, the estimator is in fact an appropriate mathematical model of the process which, based on infor...

There has been an increased use of soft-sensors in process industry in recent years. These soft-sensors are computer programs that are used as a relatively cheap alternative to hardware sensors. Since process variables, which are concerned with final product quality, cannot always be measured by hardware sensors, designing the appropriate soft-sens...

The techniques of multi-agent system bring intelligence and flexibil-ity to embedded agent/multi-agent embedded system connected to internet pre-sents a great advantage. Advantage of such multi-agent systems improves the use of expanded infrastructure. Installing simplified agents in embedded sys-tems was shown necessary due to increasing use of em...

Demands regarding production efficiency, product quality, safety levels and environment protection are continuously increasing in the process industry. The way to accomplish these demands is to introduce the more complex automatic control systems which require more process variables to be measured and more advanced measurement systems. Quality and...

In this paper network performance evaluation of three latest versions of Windows OSs; namely Windows XP®, Windows Vista™ and Windows 7™ is conducted. Network performance measurements were obtained with D-ITG (Distributed Internet Traffic Generator) on a two identical computer systems connected with 1 Gbps Ethernet crossover cable. Following metrics...

Amazon Simple Queue Service (Amazon SQS) is a message-oriented middleware in the cloud using software as a service model. It aims to eliminate the traditional overhead associated with operating in-house messaging infrastructures by providing reduced costs, simplified access to messaging resources, scalability and reliability. In order to provide th...

This work presents a simple wireless WiFi accessible web server with a web interface that provides control of different types of systems connected to an embedded system. Wireless control is created on software platform provided by Altium with modified OpenBSD driver framework. Web server is created on the top of the lwIP which is simplified impleme...

There has been an increased use of soft-sensors in process industry in recent years. These soft- sensors are computer programs that are used as a relatively cheap alternative to hardware sensors. Since process variables, which are concerned with final product quality, cannot always be measured by hardware sensors, designing the appropriate soft- sen...

Manual testing is a time consuming process. In addition, regression testing, because of its repetitive nature, is error-prone, so automation is highly desirable. Robot Framework is simple, yet powerful and easily extensible tool which utilizes the keyword driven testing approach. Easy to use tabular syntax enables creating test cases in a uniform w...

In last few decades computational power of computers has greatly increased. Highest speeds and power are still reserved for super-computers, but high-speed computers have been available for home and amateur users for some time. Normal user most of the time uses only a small amount of computational resources available; even in cases of high-strain,...

In this paper we present our methods for acoustic imaging. Our goal was to develop a fast and robust method for ship-hull inspection in dirty harbor waters by using an acoustic imaging system. The SONAR system used had 5 MHz sampling frequency, 128 channels, a 1 MHz carrier frequency and a 125 kHz bandwidth. For creating acoustic images we used sev...

Process variables which are concerned with the quality of final product cannot often be measured by a sensor. The alternative procedure is the estimation of these difficult-to-measure process variables for which it is necessary to have an appropriate process model. Process model building, based on plant data taken from the process database, is usua...

Automated form processing is a procedure that can dramatically accelerate system performance, reduce the proportion of human work and interventions, and is applicable in many areas. The aim of this paper is to describe the procedure that successfully locates various fields for data entry on scanned documents and prepare their content for further pr...

In this paper we present our Visual Studio C++ (VSC) programming environment (PE) used for SONAR signal processing and acoustic imaging. Proposed PE is implemented in combination with fast C and flexible MATLAB programming tools. SONAR imaging techniques are executed in a fast manner, by implementing them in C. With MATLAB's External Interfaces we...

The article compares the most common methods for converting measured resistance of platinum sensor to a temperature value in relation to the new adaptive algorithm applied in a compact temperature transmitter.The hardware of the temperature transduceris based on a micro controller with input/output circuits that generate an output signal proportion...

In this work we present an automated parking lot system that is managed and monitored by a video camera. We used a web camera for monitoring and the PC with MATLAB environment for managing the parking lot model. Captured frame is first converted to the grayscale image and then to the binary image with Sobel edge detection method. Image is dilated a...

Multiple servers as a mechanism for scheduling aperiodic tasks in heterogeneous environments can increase performance of real time systems. This paper describes implementation of the multiple total bandwidth server (MTBS) mechanism, a version of total bandwidth server (TBS) for distributed systems, in a simulation tool. The tool enables evaluation...

This paper describes the implementation of an algorithm for surface error detection on ceramic tiles in CUDA (Compute Unified Device Architecture). It compares the differences between the CPU and the GPU algorithm implementation, analyzes the features of CUDA GPU and summarizes the general programming model of CUDA. Paper presents the speed up gain...

This paper presents a hybrid μP/FPGA implementation in the visual inspection of ceramic tiles. The last phase of the ceramic tile production process is the visual inspection and quality control. The visual quality control is organized and performed by human vision. Due to the characteristics of human vision and its low reliability, this stage of th...

During whole production process there is a possibility of mechanical damage of ceramic tile during transporting from one production phase to another. Because of that, last phase in ceramic tile production process is visual inspection and quality control. Today in most cases in products quality control are used human resources but because of human r...

In this paper, we report on two year case study research in a software development organization which includes more than 20 architects of different social profile, knowledge and time zone locations. During that time, we built up understanding on how to support software architects in knowledge codification (converting human expertise to organized, c...

In the last few years, cloud computing has grown from being a promising business concept to one of the fastest growing segments of the IT industry. Now, recession-hit companies are increasingly realizing that simply by tapping into the cloud they can gain fast access to best-of-breed business applications or drastically boost their infrastructure r...

Novel acoustic localization device based on FPGA is presented in this paper. It is based on a FPGA multi-channel signal processing module that is connected to a sound detector array. Sound detector is made by microphones and cascade analog amplifiers. Detector also includes Schmitt trigger that generates a true/false logic signal in correspondence...

Intelligent system for automated visual quality control of ceramic tiles based on machine vision is presented in this paper. The ceramic tiles production process is almost fully and well automated in almost all production stages with exception of quality control stage at the end. The ceramic tiles quality is checked by using visual quality control...

This work proposes decomposition of square approximation algorithm for neural network weights update. Suggested improvement results in alternative method that converge in less iteration and is inherently parallel. Decomposition enables parallel execution convenient for implementation on computer grid. Improvements are reflected in accelerated learn...

Intelligent system for automated visual quality control of ceramic tiles based on machine vision is presented in this paper. The ceramic tiles production process is almost fully and well automated in almost all production stages with exception of quality control stage at the end. The ceramic tiles quality is checked by using visual quality control...

This paper presents one method about automation of tile surface and texture diagnosis. Final stage of tile manufacturing deals with surface and edge defects detection, and is still not an automated part of production. We used computer visual diagnosis and FPGA-based embedded hardware digital design to classify tiles according to surface and edge de...

Project managers must learn to recognize the signs and symptoms of disruptive conflict. Such signs would include poor communication among team members, a lack of openness, a lack of respect, unclear requirements, change between managers and employees, broken boundaries of social norms or groups, different backgrounds (educational, economic, cultura...

In this work we presented our simulator used for implementing and testing a various graph search methods. Our simulator was created in order to solve the Traveling Salesman Problem (TSP) and its variations. TSP is NP-hard in general. Variations that specializes TSP are even harder. Thus, heuristic algorithm is suitable for solving TSP and similar N...

Computational grids are useful tools for bringing supercomputing power to users by using idle resources in the network. In the following paper we give a short overview of architecture of the Alchemi grid developed on .Net platform. We created a grid application, which utilizes Rabin-Karp string searching algorithm to test Alchemi grid performances...

This work proposes decomposition of gradient learning algorithm for neural network weights update. Decomposition enables parallel execution convenient for implementation on computer grid. Improvements are reflected in accelerated learning rate which may be essential for time critical decision processes. Proposed solution is tested and verified on M...

Ceramic tile manufacturing process is almost completely automated. An exception is the final phase, i.e. quality controls, carried out by human. Production lines move relatively fast, increasing thereby the possibility of making a mistake due to a limited possibility of human eye. Visual quality requires uniform lighting with specific requirements...

This paper describes the comparison of two methods for nonlinearity correction of Platinum resistance industrial thermometers in production phase. Temperature measurement is done by industrial thermometer based on measuring inlet and is made by Platinum resistance sensor. Measuring range of such thermometers is between -50degC and +600degC. As the...

This work gives improvement of gradient learning algorithms for adjusting neural network weights. Suggested improvement results in alternative method that converge in less iteration and is inherently parallel, convenient for implementation on computer grid. Experimental results show time savings in multiple thread execution for a wide range of MLP...

In this paper are presented several possible applications in transport and industrial applications using complex-programmable logic device (CPLD)-based and field-programmable gate array (FPGA)-based technology. Problems dealing with overcoming gaps between existing local industry technology and new embedded systems technologies are discussed from a...

Important process variables which give information about the final product quality cannot often be measured by a sensor, but their value is determined based on laboratory analysis. In order to enable a continuous monitoring of a process variable and an efficient process control, it is necessary to estimate this difficult-to-measure process variable...

The developed system for distributed intelligent control of automotive lighting system is presented in this paper. Control system is based on distributed microcontroller system and its control algorithms. A technique for intelligent light intensity control based on pulse width modulation is presented and comparison with traffic safety law regulatio...

A computer based method for determination of two very important parameters of industrial manufactured thermometers is described in this paper. Some structural influences on thermal response time and immersion depth and the relevant physical principles are discussed and presented. The electrical model of thermal heat flow across the thermo-well and...

Today's industry is based on the principle of automatics. In order to increase production quality and improve production yield that reduces production costs, there is tendency to automate every phase in the production line and if possible to replace the human resource entirely. Ceramic tile industry is not an exception. In the ceramic tile producti...

We consider a modification of the well known work function algorithm (WFA) for solving the on-line k -server problem. Our modified WFA is based on a moving window, i.e. on the approximate work function that takes into account only a fixed number of most recent on-line requests. The main motivation for using a moving window is to gain control over t...

In this paper we present a design and a prototype of a self-manageable application. Self management is accomplished by usage of a rule based autonomic manager. The application demonstrates principles for combining enterprise servers and custom developed components into a system with self-configuring, self-healing and self-optimizing characteristics...

This paper describes the automated measurement system implemented in the manufacturing of platinum resistance thermometers that gives the possibility to measure, save and analyzes the quality of the main thermometer parameters. The main topic of this work is quick but accurate method to measure as many as possible count of measuring inserts in the...

In this paper is developed and presented method for failure detection in ceramic tile production using computer visual diagnostic. This method is focused on detecting of failures on ceramic tile surface in manner of highly contrasted dot shaped formation incorporated into ceramic tile surface which are result of failures in production chain. The ce...

The production of ceramic tiles has significant influence to environment due to consumption of energy sources, raw material, emission and waste that emerges throughout the production. The life cycle assessment method is used to show and test the possibility of decreasing the influence of contemporary manufacturing process of ceramic tiles to enviro...

Image processing is very often present as a method for visual inspection in industry. Automated systems for visual inspection are very important part of the quality control in production line. Quality control has been mostly performed in hard work conditions. Using automated visual systems quality control becomes easier. It performs faults detectio...

The requirements of modern manufacturing industry caused the increase of implementation of the automated systems. Their main aim is to improve visual inspection and quality control. In the ceramic tiles industry the quality control is performed in real time conditions so that tiles are classified and removed if they have defects in color, dimension...

This paper describes one method to determine the optimal approximation parameters of the sensor transfer characteristics given in table form. The main topic of this work is the parameter optimization related to the minimization of the microcontroller memory and computing the resources, while keeping the approximation error within the allowed bounda...

The image processing and analysis applied in manufacturing industry is increasing. The applications are mostly in quality control, such as visual inspection. If the processing and analysis are used in production lines for ceramic tiles, it could be very demanding and it has to be very fast. So the use of powerful computer architectures such as comp...

In this article we present an algorithm for automatic detection of surface defects on ceramic tiles. This algorithm is based on the probabilistic neural network with radial basis. To improve sensitivity of the detection procedure an image of the tile is divided into segments and one neural network is made for each segment. The discrete wavelet tran...

The aim of this research was to determine an acceptable method of texture feature extraction that could be used for a visual inspection of ceramic tiles quality. Traditional extraction of statistical features has been carried out as well as feature extraction based on local binary pattern operators. For the purpose of testing the proposed methods g...

The texture feature extraction method could be used in ceramic tiles machine visual inspection. The ordinary method of visual inspection in ceramic tiles production process is performed by a human vision. The results are inhomogeneous tile classes and rather slow and boring inspection. There are papers which describe methods developed for quality i...

A high level of diversity, timing variability and renewability characterizes today's heterogeneous computing environment. In addition to static-dynamic mapping and prediction, the remapping procedure can significantly improve system performance. Causes of remapping, as well as adjustment of threshold, period, horizon and shift determine remapping....

Appropriate mapping procedures make heterogeneous computing environment especially suitable for the execution of various computer-intensive applications. The paper shows a static dynamic mapping procedure relying on the multicriteria model. Model parameters describe the application, platform, mapping and user. They are divided into static and dynam...

Heterogeneity of computer environment allows execution of large diverse applications, but it also simultaneously aggravates mapping. We present a combined multicriterial mapping based on the MEVSP model. Model parameters originate from the level of application, platform, mapping and user. The most suitable prediction methods are long-term performan...

Theoretical foundations of scheduling in the course Real-Time Systems of the undergraduate studies program are extended by the usage of the developed visual software tool. The tool enables teaching of simulated fixed-priority scheduling algorithms. The user simply sets the simulation and algorithm properties and loads the prepared input task sets f...

The image processing described in this paper is used for visual quality control in ceramic tile production. The tile surface quality depends on the surface defects. The described image processing is based on the neural network approach. The described diagnostic algorithm is presented to detect surface failures on white and coloured ceramic tiles. T...

The image processing used for visual inspection and quality control in a serial production is described in this paper. We used the discrete wavelet transform -DWT in our failure detection algorithm. To achieve robustness as well as good sensitivity of the algorithm, we divide the images into segments. The difference of the wavelet coefficients maxi...

The image processing described in this paper is used for visual quality control in ceramic tile production. The tiles surface quality is described by the surface defects. The described image processing is based on the discrete wavelet transform method. The diagnostic algorithm is described. It is based on comparing of the wavelet coefficients of th...

There is often a mixture of periodic and aperiodic task sets in scheduling. This mixture is scheduled by the combination of periodic and aperiodic task scheduling algorithms. Validation of these algorithms could be made by the developed visual software support. Timing properties of the scheduling algorithms are in opposition to the resource utiliza...

The image processing applied on the original tile image and the replica images in serial production is used for visual quality control. The image of a tile that contains no visual quality error represents the original image. The images of the tiles from the production line that could contain some of the visual quality errors represent the replicas....

The fault tolerance of the control system in this paper is based on cold standby and software redundancy. The control system is a microprocessor modular system. It consists of standard nonredundant modules and specific additional modules. The fault-tolerant control system performs the validation of the active microprocessor unit and the actualizati...