bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamical Traffic Engineering in Software-Defined Network
Authors: Yu Yi Fan , Li Yong , Jin De Peng
Published: August 2014

Software-Defined Networks (SDN), as newly proposed network architecture, has a great potential in optimizing network traffics. In SDN, the control plane is separated from the data plane. With the help of the centralized controller, we can gather information of the network in real time. In this work, we propose a practical two-stage approach for traffic engineering that takes advantages of SDN. The approach not only assures every newly injected flow gets a suitable route that does not have too much payload on it, but also schedules the overall flows so that they are distributed more equally in the network. Furthermore, we demonstrate its efficiency in terms of port speed and compared it with port speed under the default routing decision. We also use linear programming to find the optimal solution and compare it with our result.
Mini UAV Design and Manufacture with Bungee Launched / Parachute Recovery
Authors: Shyu Lih Shyng , Hsiao Yung Chia
Published: August 2014

In the past ten years, the R&D of UAV (Unmanned Aerial Vehicle) is very popular and has the trend to replacing with the manned aerial vehicle due to its low-cost and high-mobility. According to the specifications, this project completes special contour and function of a mini-UAV design and passes the strict fabrication, prototyping, and aerial test processes. With the advantages of long flight endurance, speedy assembly/disassembly, simply contour, and portable, the developed mini-UAV has the capabilities of bungee launch and parachute recovery. Thus, it makes much progress in Taiwan’s mini-UAV area.
Mathematical Programming Combined with Cascade Analysis in Refinery Hydrogen Networks Including a Purifier
Authors: Ma Li , Deng Jian Qiang , Cao Zheng
Published: August 2014

Efficient research method represents the primary content of hydrogen networks optimization. In the view of methodology, as pinch analysis is not specialized in precisely matching a network and mathematical programming is likely to induce convergence difficulties, a combination of both is liable to avoid their shortcomings. This paper introduces a detailed process, combining cascade analysis and mathematical programming method, to optimize a refinery hydrogen network with a purifier. A hydrogen cascade analysis instead of traditional pinch-point methods is deduced to rapidly obtain pinch-point purity without tedious iterative. On this basis, the location of the purifier could be pinpointed and a concise superstructure with pinch point and the purifier is constructed. Then a superstructure-based mathematical programming model is presented. A case study is finally carried out to examine the applicability and advantages of the proposed combination approach. The calculation result verifies the optimization of the method as well.
Degradable Scaffold Microstructure of Artificial Bioactive Bone Fabricated by 3D Braiding Method
Authors: Liu Jie
Published: August 2014

A novel fabrication of degradable scaffold is presented by using several biomaterials and growth factor (GF). Chitosan fibers can be braided into the internal fiber microstructure of the scaffold by a three-dimensional braiding (3DB) method, and rapid prototype & rapid tools techniques can be used to rapidly fabricate the outer shape mold of the scaffold. The scaffolds with 3D fiber architecture had obviously accelerated bone regeneration in comparison with the control. In detail, the materials biodegraded inside and outside and the bone ingrowth first occurred along the chitosan fibers in the scaffold. In summary, the method in this paper not only can be easily shaped but also cannot change the bio-properties of materials and GF since it does not need high temperature sintering and not produce heat, so the actions of the several biomaterials for bone regeneration interacted simultaneously through the interconnectivity macrochannels in the in-vivo scaffolds, which left by the biodegradation of the internal fiber.
Kinematic Model of Nonholonomic Mobile Robots
Authors: Jezný Jaromír
Published: August 2014

Provided in this article is a general overview of modeling nonholonomic mobile robots. Emphasis is given to the structural characteristics of kinematic models, taking into account the mobility restrictions caused by various links. Based on the degree of mobility and the degree of controllability it is possible to divide wheeled mobile robots into multiple groups, regardless of the robot construction and the wheels arrangement.
Snake Robot Movement in the Pipe Using Concertina Locomotion
Authors: Virgala Ivan , Dovica Miroslav , Kelemen Michal , Prada Erik , Bobovský Zdenko
Published: August 2014

Inspection tasks of pipes or channels are part of the engineering practice. In the past there were investigated conventional approaches like wheeled-based mechanisms. This paper deals with unconventional approach - snake robot moving in the pipe. In the paper locomotion pattern of concertina is introduced and subsequently kinematic model of concertina locomotion is established. Main requirements and conditions of presented locomotion pattern are stated. Using software Matlab the kinematic model is simulated according designed locomotion pattern in order to verify the kinematic model. For experimental purposes the experimental snake robot – LocoSnake is used. Simulation and experiment are compared and evaluated.
Deformation and Stiffness of Spur Gearing Solved by FEM
Authors: Malák Miroslav
Published: August 2014

Gear teeth are deformed due to the load. Recently, at ever faster evolving computer technology and the available literature, we can encounter modern numerical methods, such as finite element method (FEM), which can serve as methods for the determination of deflection gearing. This paper deals with stiffness and deformation of teeth of spur gears solution by finite element method.
Actuation of Control System for Racing Engine Using Active Data Maps
Authors: Tonhajzer Roman , Puškár Michal , Kopas Melichar , Faltinova Eva , Čopan Pavol
Published: August 2014

The modern systems developed for a control of ignition and fuel injection in the racing piston combustion engines require a continuous supplementation of the input information, together with permanent monitoring and correction of these input data. Such operations are performed by means of specialized software, which is able to decode the maps of active data fields as well as to modify them afterwards in the framework of the required values. The correct editing of the data field enables a faster and more accurate distribution of the active values.
Design of Control of DC Motor
Authors: Miková Ľubica , Kelemen Michal , Maxim Vladislav , Jezný Jaromír
Published: August 2014

In current practice the use of mathematical models is substantially widespread, reason being the recent increase in development of programs for this purpose, with the option of model simulation in a virtual environment, proportional to the evolving computer technology. The article contains a mathematical model created using Matlab program. The simulation results are compared with scientific literature that addresses DC motors and evaluated. For simplicity, a graphical interface was created.
Optimization Methods in the Design of Electromechanical Actuators
Authors: Wagner Juraj
Published: August 2014

The paper deals with the use of optimization methods in the design of electromechanical actuators. A brief introduction gives a theoretical basis for optimization methods. The following parts are aimed at specific opportunities and methods of the use of optimization techniques in the design of electromechanical actuators selected.
Increase of Tool Steel Durability in Abrasion Wear Conditions
Authors: Orečný Martin , Frankovský Peter , Lacková Petra , Buršák Marián
Published: August 2014

The article proposes possible increase of durability of tool steel X210Cr12 as regards working conditions under consideration of abrasive wear. From such steel tools are made for pressing wooden briquettes and saw dust waste. In practical environment a condition is held that if a material should work in abrasive wear conditions, it should have high hardness and should contain carbides in the structure. The proposed paper deals with the heat and chemical-heat treatment (nitriding) of tool steel which is working in hard abrasive wear conditions. From the obtained results it is not easy to conclude a definitive conclusion or to set the boundaries between the factors that are responsible for wear resistance. It is shown that the chemical-heat treatment can in the last step of the heat treatment lead to an increase or even to a decrease in the abrasive wear resistance of the material. The aim of the paper is to set a proper heat treatment of materials used for pressing in abrasion wear conditions.
Effect of Time Scaling and Mass Scaling in Numerical Simulation of Incremental Forming
Authors: Surech Kurra , Regalla Srinivasa Prakash
Published: August 2014

In incremental sheet forming (ISF) the tool moves along the specified trajectory and deforms the sheet in to required shape. In the present paper incremental forming process is simulated using explicit finite element software LS-DYNA. The computational time for the simulation of ISF is very long due to long tool paths used in the process. To overcome this problem time scaling and mass scaling are used in the present paper. The effect of time scaling and mass scaling on forming forces, plastic strain, internal energy, kinetic energy, thickness distribution and computational time is studied. A continuously varying wall angle conical frustum is simulated for this study. Extra deep drawn steel, which is most commonly used in automotive applications, has been used as a blank material. Thickness distribution obtained with different mass and time scaling factors is compared with experimentally measured thickness distribution.
Mechanisms for Small and Micro Robotic Devices
Authors: Havlík Štefan , Hricko Jaroslav
Published: August 2014

The paper deals with problems of designing and evaluation of compliant mechanisms for small and micro robotic devices. These kinematic mechanisms are usually made from a piece of elastic material in case of positioning systems, or, create the flexural body for multi-component sensing devices. The compliance characteristics mechanical segments: joints, arms, are discussed and the procedure for evaluation / comparing characteristics of particular segments, as well as whole elastic structures is proposed. It is briefly discussed that mechanisms for this kind of devices should integrate functional features of positioning and sensing systems. The concept of the x – y micro positioning mechanisms with two-component force sensing capability is presented as an illustrative example.
Automatic Detection of the Connected Module and its Orientation
Authors: Bobovský Zdenko
Published: August 2014

This paper describes a hardware design of connection places for an automatic detection of a newly connected module and detection of its orientation for use in the self-reconfigurable modular robotic system. It also describes a mechanical design for an energy and information transfer between modules in the system. This paper also describes testing of an automatic detection with a graphical display of the results for an actual shape of a newly created kinematic structure of the system.
Connecting Interface for Construction of Modular Structures
Authors: Svetlík Jozef
Published: August 2014

Article deals the issue of connecting modules in modular structures applied in robotics, manufacturing engineering and technology in general. Themselves joining motion module is implemented interconnecting interfaces, which are placed stringent requirements of strength, stiffness, weight and the possibility of transporting energy and data flow through the interface. On the market can be founds similar solutions. However, these solutions are mostly designed for output stages of industrial robots. Primarily, these solutions focus on the end effector exchange systems in robotics. To determine the total track modular machine was necessary to design a new model for connecting interface that meets all the requirements placed on it.
Application Area of Multiagent Systems – Modular Robotics
Authors: Jánoš Rudolf
Published: August 2014

The main application area of multiagents systems, demonstrated in this article is the modular robot, a type of robotic system that is composed of many autonomous modules. The paper shows theoretical and design approaches to the solution of metamorphic service robots. It gives selected specific questions and problems connected with its design and construction. While various decentralized algorithms have been developed in the field of modular robotics, most approaches lack theoretical treatment; furthermore, most are specialized for particular tasks and dificult to generalize to other modular robot tasks or configurations. Theoretical understanding allows us to identify the scope of this approach and to further generalize it to a broader application area. [1]
Mathematical Model Design of Small Helicopter - Unmanned Aerial Vehicle Development
Authors: Bačík Ján , Sivý Radovan , Šlapák Viktor
Published: August 2014

The paper introduces main simulation principles of small helicopter T-Rex 600. The emphasis is on main rotor parts, the Bell-Hiller mixer and flybars. Main rotor performs three basic tasks: thrust generation, propulsion, longitudinal and lateral control. Flybars system directly affects the stabilization of helicopter as well as direction control of thrust vector of the main rotor.
The Chosen Aspects of Self-Reconfigurable Robots
Authors: Vagaš Marek , Baláž Vladimír , Semjon Ján , Koukolová Lucia
Published: August 2014

In this paper we have shown and discuss the problematic of self-reconfigurable robots. Self-reconfigurable robots are modular robots that can dynamically and intelligently reconfigure their shape and size to accomplish difficult missions. This paper gives an chosen aspects of self-reconfigurable robotics with regards to individual aspects (technical, control, morphology) and basic consideration to the description of some individuality at this area.
Simulation of Collision Situations in RobotStudio
Authors: Baločková Lenka , Prada Erik , Titka Attila , Lipták Tomáš
Published: August 2014

The article deals with the problem of the collision condition of robotic device, which is possible to be revealed by spatial simulation. In addressing the collision condition, RobotStudio program was used. It includes collision detection functions. Collision detection function automatically monitors objects and indicates the collision, which may arise during the operation of the robot. In my case, collision condition occurs between the stationary part, which is a component part and moving part, which is a burner.
Modelling of Dynamic System Characteristics of Deep Hole Drilling Process with Tools about Flexible Stifness
Authors: Zubrzycki Jarosław , Świć Antoni , Opielak Marek
Published: August 2014

For an accepted physical model with allowance of cutting "on a trace" phenomena, the initial mathematical model for want of processing deep hole is considered. In the work has been presented principal assumption to modeling of vibrating process of deep hole drilling. To implement the process were used specially developed construction of waveguide transducer to generate the self-excited vibrations. The use of the transducer was aimed at increasing the efficiency of the process and improve the quality of performed hole. Performed model was used to process numerical researches to obtain the amplitude-phase characteristics of the drilling parameters. Then they were compared with the appropriate characteristics obtained from experimental studies.
Some Aspects of Interoperability of Enterprise and Manufacturing Systems
Authors: Pękala Jacek
Published: August 2014

The exchange of data between systems is a very complex process. This is the resultant of a huge variety of communication tools, the differences in the systems' structure, data storage, etc. Therefore, integration of systems - highly desired by businesses - becomes equally important challenge as the possession of the systems. Systems integration, however, is responsible only for the exchange of information. Wider notion from integration is interoperability. Treated as a systems property, allows not only to exchange information but also mutual understanding between them. The paper presents the concept of middleware application that could provide the interoperability of enterprise systems. The application structure was based on three aspects: the transformation, completeness verification and validation of data that can be exchanged between ERP and MES systems. Each of these aspects is discussed in this paper. The application uses a unified model of data based on a dedicated language B2MML.
Smart House - The Building Management System
Authors: Piotrowski Andrzej , Nieszporek Tadeusz
Published: August 2014

Unit recently, electronic management systems were reserved exclusively for production systems. The development of technology has enabled the construction of "intelligent buildings", that is buildings equipped with advanced systems to supervise the operation of household equipment. Control systems monitor the condition of the rooms (temperature, humidity) using sensors, and the measurement is analysed by a program resident in the memory of a microcontroller which, based on a developed algorithm, makes the decision to activate the actor – an actuating device (heater, air conditioner). The system acts like a robot, which creates the picture of the world with its sensors and then, based on its built-in "intelligence" (a program), performs a specific operation. The only difference is in the appearance; instead of a human-shaped android, we have a "thinking" building. The intelligent building control system enhances the living comfort of the inhabitants and reduces the energy intensity. A characteristic feature is the user's ability to interfere in equipment operation parameters, e.g. to change the temperature. Therefore, control systems feature a simple and functional interface suited to the skills of an average user. It is activated on any device with an internet browser to enable the remote control of the system.
Recent Advances in Planetary Gearbox Fault Diagnosis
Authors: Li Ming Hui
Published: August 2014

In order to guarantee the quality of remanufacturing planetary gearbox products, fault diagnosis and evaluation are the key links in the process of remanufacturing engineering. The faults will lead to cyclical impact, causing the transient response of periodic vibration signals, by studying the fault mechanism and using modern signal processing methods, the fault features can be extracted and analyzed. The purpose of this review is to present a summary about the application of the vibration test technology in remanufacturing planetary gearbox fault diagnosis, including the following main aspects: the fault diagnosis theories,the sidebands spectrum structure and the application of modern signal processing methods. In addition, some key problems in planetary gearbox fault diagnosis are analyzed and the approaches to solve these problems are discussed.
A Self-Adaptive Corner Detection Algorithm for Low-Contrast Images
Authors: Sun Liang , Xing Jian Chun , Wang Shuang Qing , Wang Shi Qiang
Published: August 2014

In order to effectively inhibit the image dithering caused by wind-induced vibration in the security monitoring system, it calls for the extraction and match of the feature points of the sequential frames. Harris corner detection algorithm is a widely-employed characteristics extraction algorithm in the image processing. In the security monitoring field, images and videos photographed are characterized by large scale, high pixel and low contrast degree. The classical algorithm often fails to effectively obtain the feature points while handling the images and videos of the kind. Concerning the above problems, this paper puts forward an improved self-adaptive corner detection algorithm. Firstly, this paper employs the self-adaptive gray threshold comparative results of the of every point with the surrounding eight neighborhood points to select the preselected points of part of the corners. Following that, this paper classifies the preselected points into three types according to certain rules and the value of the already selected self-adaptive gray threshold. At last, according to the classification results, this paper uses different corners to test function threshold and the preselected points as well to eliminate the peripheral points and the pseudo-corners so as to gain the genuine corners. After verifying the above improved algorithm in the practical scenario in the security monitoring, the results of this paper prove its effectiveness, feasibility and its advantages in terms of robustness.
Optical Trap Stiffness Online Measurement System Based on FPGA
Authors: Li Peng Fei , Li Jing , Zhu Chun Li
Published: August 2014

For investigating the mechanical properties of optical tweezers, a data collection/process/control system based on FPGA is designed and developed to measure the optical trap stiffness. A four quadrant detector is used to track the positions of the trapped microsphere, the digital data converted by a high precision ADC is transferred through the USB interface into PC for processing and displaying, and the PC controls an electronically controlled platform to realize zero alignment of the four quadrant detector. Experiments show that this system could be effectively used for on-line optical trap stiffness measurement.
Distribution Law of Excavating Load of TBM Disc Cutter and Cutterhead
Authors: Zhu Xiang Heng , Xia Yi Min , Ouyang Tao , Yang Kai
Published: August 2014

Cutterheads and disc cutters are the key components of Tunnel Boring Machine (TBM) used to fulfill the rock-breaking task. In order to study the variation and distribution law of cutting forces induced by disc cutters on TBM cutterhead, a finite element model of rock-breaking process is established based on the extended Drucker-Prager yield criterion for rock and then the excavating process of cutterhead is simulated. The simulation results show that: in the rock fragmentation process, the rock-breaking forces are step changing; with the increase of installation radius, the vertical forces of inner and face cutters increase, while the lateral forces decrease; with the increase of installation angle, the vertical forces of edge disc cutters decrease, while the lateral forces increase; the mean total thrust and torque of cutterhead are 5418.2 kN and 1624.4 kN·m respectively, the simulation results are verified by engineering data.
Real-Time Signal Denoising Algorithm in Wheel Force Transducer
Authors: Wang Dong , Lin Guo Yu , Zhang Wei Gong
Published: August 2014

The wheel force transducer (WFT) is used to measure dynamic wheel loads. Unlike other force sensors, WFT is rotating with the wheel. For this reason, the outputs and the inputs of the transducer are nonlinearly related, and traditional Kalman Filter is not suitable. In this paper, a new real-time filter algorithm utilizing Quadrature Kalman Filter (QKF) is proposed to solve this problem. In Quadrature Kalman Filter, Singer model is introduced to track the wheel force, and the observation function is established for WFT. The simulation results illustrate that the new filter outperforms the traditional Unscented Kalman Filter (UKF) and Extended Kalman Filter (EKF).
Strength Analysis of the Railway Truck Body Based on ANSYS
Authors: Fang Zhe , Han Mei
Published: August 2014

Tub-type car is a kind of truck which increases the usage of the rolling stock clearance. Its special tub-shaped structure provides more space for cargo that increases the load utilization factor. The analysis of the structural strain strength proves that the design and material of the tub-type car body fit the actual demand according to the rules of the . The stress of every point everywhere on the structure of the car body is below the yield stress which ensures the safety of the car body during the operation. The simulation results reflect the stress distribution of the whole car body which provides the reference for design and test.
Comprehensive Study and Review on Maglev Train System
Authors: Ahmed Raheel , Jun Yu Li , Azhar Muhammad Fawad , Junejo Naveed Ur Rehman
Published: August 2014

Electromagnetic levitated systems commonly used in the field of people transportation, tool machines frictionless bearings and conveyor systems. In the case of high speed people transport vehicles, the electromagnetic levitation offers the advantage of a very silent motion and of a reduced maintenance of the rail. Magnetic levitated trains requires the guidance force needed to keep the vehicles on the track is obtained with the levitation electromagnets, Particular shapes of the rails and to a clever placement of the electromagnets with respect to the rails helpful and effective to achieve the goal. This article gives the basic idea of the electromagnets trains and its control system mechanism
Application of Immune Algorithm Optimizing PID Parameters in Simulink
Authors: Zhang Sheng Bo
Published: August 2014

The PID control model of alternating current governor system was established in Simulink and using immune algorithm to optimize PID controller parameters. It takes PID controller parameters as antibody and the optimal solution as antigens,dynamically adjust PID control parameters in the control process through the immune algorithm of memory cells and antibody concentration regulation mechanism of genetic algorithm.. The antibody coding method, diversity evaluation of the solution, immune operation and Optimization method of steps were detailed. The simulation results show that the immune algorithm was fewer iteration times and high efficiency. The optimized control system reduced the overshoot, improved the response speed and improved the system performance which is a kind of effective optimization method to PID controller parameters.
The Control System Design of the Pod Based on Fuzzy-PID
Authors: Wang Bao Gui , Liu Yan , Song Yan Bo , Wang Jian , Zhang Zhi Guang
Published: August 2014

When the pod works in the air, pod can produce the overshoot and stability. To solve this problem, the study demonstrates that the fuzzy-PID was used to control the pod. Simulink simulation module of Matlab was using to establish a control system model pod exterior orientation framework to verify the simulation, anti-jamming performance and tracking performance of the system. The results show that fuzzy PID control method can make the system have good stability, noise immunity and tracking capability.
A Research on the Methods of Fatigue Analysis for Vehicle Body Based on Real Road Conditions
Authors: Zhong Xin Cai , Wu Zhen Yu , Song Kai
Published: August 2014

Complex road excitation,has long been the key and difficulty of simulation technology for vehicle fatigue. The main error source of the technology is the deviation that virtual road and simulation speed are not true of proving ground test. An improved method was presented. The long-distance virtual road which consisted of a variety of typical pavements was built and used as the excitation, and the measured speed was applied to the virtual test. So the virtual test could be a true reflection of the road conditions of the proving ground, and improve the accuracy of the load that the fatigue analysis required. Finally, the linear superposition method was used to rapidly predict the fatigue life. In the durability project of a certain vehicle,it was proved that the virtual test could reproduce the road conditions of Hainan proving ground by comparing with the measured values of accelerations of wheel hub. The example of the front wheel cover plate proved that this method could efficiently and accurately predict the vehicle body fatigue life.
Influence of Different Types of Fine Aggregate on Cement Composites Resistance to High Temperatures
Authors: Melichar Tomáš , Bydžovský Jiří
Published: August 2014

The paper discusses the impact of several selected aggregates on the basic material characteristics of cement composites. Both artificial and natural aggregates (four types in total) with different mineralogical composition were evaluated. The specimens were exposed to environments with the temperature up to 1000°C and then subjected to physico-mechanical tests. For the follow-up development of polymer-cement mortars, we selected two types of aggregates – fly ash aggloporite (FAA) and amphibolite (AMA).
Utilisation of Polyurethane (PUR) Granulate in Development of New Insulating Materials
Authors: Zach Jiří , Novák Vítězslav , Hroudová Jitka
Published: August 2014

At present we can often see a development of new perspective materials using waste raw materials and not only in building industries. Still growing industrial waste amount together with not utilizable substances whose recycling is quite energy and finance demanding are the reasons. In addition it also brings a notable stress for the environment which further influences human health. The paper deals with a development of insulating materials based on waste PUR granulate generated as waste during PUR foam panel shaping. The aim was to develop insulating materials with good thermal insulation and eventually acoustic properties as suitable alternatives to present commonly used insulation materials in the market. Cement and subsequently PUR foams were selected as binders for waste granulate. Utilization of secondary raw materials in order to get new insulating materials with high added value is contribution of such a development.
Study on the Process of Creating Fly Ash Body
Authors: Černý Vit , Keprdová Šárka
Published: August 2014

Production of artificial aggregate by clinkering process is currently relatively well-known way to efficiently use the potential of fly ash for building materials. Principle of clinkering can reduce the cost of natural gas and other potential external sources of heat through the use of own combustible substances. Course of firing and aggregate properties significantly depend on the type and character of the fly ash or fly ash mixture. Due to the high heterogeneity of these materials is relatively difficult to assess the impact of specific parameters (grain size, the content of Fe2O3, SiO2, CaO, amorphous phase, etc.). Due to the experimental testing of a large number of different types of fly ash and their mixtures, it will possible to verify at least some principles based on experience with the production of ceramic body. This article discusses the results of the sub-tests, dealt with influence of physico-mechanical properties, chemical and mineralogical composition of fly ash on the quality of the resulting ash body.
Thermal Insulating Alkali-Activated Systems
Authors: Khestl Filip , Boháčová Jana , Staněk Stanislav
Published: August 2014

The paper deals with a laboratory research and development of alkali activated system with thermal insulating properties filled with low density materials. The experiment was focused on compressive strengths and heat conductivity of prepared materials. The purpose was to prepare durable but also isolating material based on alkali-activated blast furnace slag.
Dielectric Spectral Differences for Concrete with Shredded Automobile Tires as an Admixture
Authors: Lunak Miroslav , Kusak Ivo , Štefková Daniela , Tupý Michael , Sotiriadis Konstantinos
Published: August 2014

This paper gives the information about the dielectric testing of the cement-based composites prepared from a mix of cement mortar and quartz sand, with shredded automobile tires as an admixture, which were intentionally degraded by high-temperature treatment (in the temperature range from 0 °C to 400 °C). The monitoring of structural changes in the thermal stress is very important, for example determining the reliability of the whole structure and influence of polymer admixture on measured dependences. Development of electrical parameters and permittivity at each temperature area reliably shows structural changes and the structural reliability.
Ecological Suitability Evaluation of Composites with a Defined Waste Content
Authors: Urbánková Kristýna , Kukletová Ilona , Štegnerová Hana
Published: August 2014

Economic and environmental dealing with waste requires development of new technologies for their usage. An incorporation of industrial waste material in construction materials and products is one of the options how to reduce raw materials cost and save natural sources of raw materials. In case of wastes utilization as a component of building materials, it is necessary to know their technological and ecological suitability. This study deals with some ecotoxicological and analytical methods for evaluation of ecological availability of composites with defined content of waste. These methods describe impact of the substances on the environment and living organisms.
The Influence of Sodium Sulphite on Portland Clinker Hydration
Authors: Hajdúchová Miroslava , Šoukal František , Másilko Jiří , Havlica Jaromír
Published: August 2014

AFm phases, called also (Al2O3-Fe2O3-mono), are a common term for the hydration products with general formula [Ca2(Al,Fe)(OH)6∙(X)]∙y H2O, where X means e.g. OH-, SO42-, CO32-. AFm phases are formed when the corresponding phases are present in adequate concentrations in the solution under the room temperature. The incorporation of sulfite anions in the structure of lamellar AFm phase will be shown. The presence of monosulphite in the Portland clinker system was investigated by infrared spectroscopy, XRD and SEM analyses.
Porosity Evaluation of Alternative Materials Based on Portland Cement
Authors: Pařízek Ladislav , Bartoníčková Eva , Bílek Jr. Vlastimil , Kratochvíl Jiří
Published: August 2014

High energy requirements and the resulting economic demands due to the production of Portland cement leads to tendency to replace a portion of cement with secondary raw materials or to use other alternative binders. Among the commonly used cements replacements is currently fly ash which is produced during the coal combustion. In this paper the influence of cement/ash ratio in a paste on paste’s porosity is investigated using mercury intrusion porosimetry.
Stabilization of Indoor Humidity by Rammed Earth
Authors: Richter Jan , Staněk Kamil , Havlik Filip , Růžička Jan
Published: August 2014

Clay and earthen materials are highly hygroscopic and thus able to effectively adsorb and release moisture from their surroundings. This paper analyses the ability of rammed earth to stabilize internal course of relative humidity. A numerical hygrothermal model is introduced and validated using a set of measured data according to IEA Annex 41. The model is then used to determine the stabilization effect of rammed earth in a residential room with defined moisture sources and ventilation rate. The simulation is performed for gypsum boards, concrete and red brick as well and a clear comparison is made. The results show that the rammed earth can most effectively moderate the indoor air humidity variations; followed by concrete, gypsum boards, and red brick.
Testing of Surface Photoactivity of Fibre-Cement Composites
Authors: Boháč Martin , Staněk Theodor , Urbánek Petr
Published: August 2014

Paper deals with testing of surface photoactivity of fibre-cement composites. Self-cleaning ability, de-NOx activity, visual stability and weathering resistance were tested. Carriers of photoactivity were four different nanopowders with high content of anatase; crystalline form of TiO2. Photocatalytic properties of TiO2 particles are maintained even after mixing with cement in composite matrix. Natural photolysis as reaction of material and UV light is accelerated in presence of a proper form of TiO2 as a catalyst which by producing free radicals is able to oxidize organic matter and even small inorganic particles. Oxidized material is mostly less harmful considering the de-NOx process and decomposition of other gaseous pollutants. By this reaction the surface of composites containing large number of TiO2 particles is able to maintain its original appearance by so called self-cleaning ability.
Effect of Admixture Dosage and Specimens Age on Mechanical Fracture Parameters of Lime Mortars Enhanced by Burnt Clays
Authors: Šimonová Hana , Havlíková Ivana , Navrátilová Eva , Schmid Pavel , Rovnaníková Pavla , Keršner Zbyněk
Published: August 2014

In the restoration of historic buildings with priorities of historic preservation there exists an effort to modify the mortars by admixtures which are in compliance with historical materials and techniques. Therefore the specimens were made from lime mortar modified by brick powder or metakaolin. The reference mixture used only hydrated lime while the other mixtures were enhanced by brick powder or metakaolin in the amounts of 25, 50 and 100 % of the weight of hydrated lime. This paper presents the results of three-point bending fracture tests obtained by using double-K fracture model. The specimen’s age was 90 and 150 days.
Problems of Watertight Concrete for the Concrete Tunnel Lining
Authors: Hubáček Adam
Published: August 2014

The paper focuses on the problems of concrete for watertight tunnel lining. The theme is currently quite topical in the Czech Republic and abroad. The accent is put particularly on the requirements and properties of fresh concrete or self-compacting concrete for manufacture of specific concrete structures. Properties of hardened concrete will be also observed; in particular compressive strength, resistance to pressure water, durability and other parameters.
The Role of Metakaolin Fineness on Rheological Properties of Cement Pastes
Authors: Boháč Martin , Opravil Tomáš , Bartoníčková Eva , Frajkorová Františka , Palou Martin
Published: August 2014

Viscoelastic properties of Portland cement-metakaolin fresh pastes were measured using rotational rheometer. In mixtures 10 % of Portland cement was replaced by various fractions of metakaolin with different particle size distribution. The role of the fineness of metakaolin was revealed characterizing flow, adhesion and creep of the fresh pastes.
Recycling Process of the Aluminium Cans as an Example of the Renewable Material Sources
Authors: Škůrková Katarína Lestyánszka , Ingaldi Manuela
Published: August 2014

Nowadays recovery technologies of the renewable material sources are searched. Aluminium is one of the materials recovered in this way. It is recovered primarily from used beverage cans. These cans are normally back on supermarket shelves as new beverage cans in 6-8 weeks. With a growing percentage of the cans made from aluminium, because of its lightweight qualities, this ensures a healthy market for aluminium can recycling. The main aim of the paper was to show Economic aspects of waste utilization and to present a process of Recycling of the aluminium can. In this way it was possible to show that the concept of renewable material sources is not just a theoretical concept, but the action visible in the economy and very desired by the company due to the reduction of the production costs.
Study of Selected Characteristics of 8-Cell HHO Generator Using Various Concentrations of NaOH Solutions
Authors: Kuracina Marcel , Fiala Jozef , Soldán Maroš
Published: August 2014

The aim of the contribution is to carry out the study of the conditions of HHO gas production. All of the measurements were executed on dry cell HHO generator made of 8 stainless electrodes with NaOH solution as an electrolyte. Three concentrations of NaOH solutions (5%, 10% and 20%) were used and the changes in volt-ampere characteristics, efficiency and hourly volume performance were monitored and results were processed and compared. The KOH solution is considered as a best available electrolyte from the perspective of stability and moreover it is more suitable in cold outdoor conditions. However, the NaOH solution provides higher maximum efficiency of HHO gas production. Some recommendations to increase the efficiency of the generator are described in the conclusion.
PCBs and PAHs Restrain the Use of Sludge as a Renewable Resource
Authors: Kučerová Radmila , Sezima Tomáš , Sikora Eugen , Truxová Ivana , Kučerová Lucie , Klimko Tomáš , Matúšková Veronika , Krečmerová Pavlína
Published: August 2014

The aim of this research is to reduce the quantities of polyaromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in the samples of non-hygienized sewage sludge via laboratory biodegradation. Pure bacterial cultures of Pseudomonas putida, Rhodococcus sp. and their mixture in 1:1 proportion have been used. The laboratory experiment lasted for 28 days and the acquired values were compared with Decree 294/2005 Coll. The obtained results imply that biodegradation of such contaminated samples is practicable. Using the bacterial mixture, over 85 % Σ of PCBs were degraded, and applying Rhodococcus sp. as much as 95.86 % of the original concentration of PAHs were removed.
Contaminant Resistance of Buildings in Emergency Planning Zones
Authors: Řehák David , Pupíková Jana
Published: August 2014

The article defines a theoretical basic research of possibilities to increase resistance of buildings in the zones of emergency planning of nuclear power stations and chemical facilities. It presents the key measure of population protection, of a repressive character, which is a provisional sheltering based on using natural safety attributes of buildings. Depending on this measure it defines basic physical attributes of building materials and technical requirements for buildings located in emergency planning zones. The end of the contribution presents possible ways to evaluate safety attributes of buildings in terms of permeability of radioactive and chemical substances.
Aspects of Ecodesign when Designing a Retort with Decreased Emissions in the Production of Biochar
Authors: Mitterpach Jozef , Adam Christoph , Samešová Dagmar
Published: August 2014

The paper pinpoints the important aspects of ecodesign when designing a retort with decreased emissions in the production of biochar. When designing changes in the construction of equipment for the production of biochar, the requirements for minimum material and energy demands and the need to reduce emissions to the environment were taken into account. In the pyrolysis processes for the production of biochar, we mainly monitored the following inputs and outputs from/to the environment using life cycle analysis and ecodesign. When the decreasing emissions aspect was not included in an ecodesign, the measurements showed standard damage to the atmosphere characteristic for the production of biochar. The results of measuring emissions from the production of biochar in a retort with decreased emissions showed a significant decrease in emissions. Designs take into consideration the need to minimise the local materials available for the production of equipment for the production of biochar and the availability of raw materials for biochar (mainly accessible and suitable waste). The overall environmental profile (assessment) of biochar is improving based on this construction and conceptual design. Using such a strategic approach, other applications for ecodesign, inventory analysis and assessment of the life cycle of biochar are possible.
Liquidation of Fires of Photovoltaic Panels
Authors: Šimčák Miroslav , Majerová Edita
Published: August 2014

Solar energy is the most important source of renewable energy. At present, the consumption of energy resources is very high and the existing stocks are extremely limited. This paper considers the acquisition of energy through the photoelectric effect, whereas the rapidly increasing demand for photovoltaic panels and solar power. The question is how to design the proper size and location of the photovoltaic cell, not only in terms of the effectiveness of economic recovery, to achieve the greatest energy utilization but particularly in terms of fire protection. Data on fires photovoltaic power plant were processed by statistical methods, because we do not know the relevant estimates the frequency of fires.
Results of Forest Fuel Spatial Distribution Mapping for Fire Simulation Purposes – Case Study
Authors: Majlingová Andrea , Sedliak Maros , Tuček Ján
Published: August 2014

In the paper we introduce an approach of mapping of surface forest fuel spatial distribution using the results of field survey and functions and tools of the ArcGIS environment. The analysis was provided for the Stare Hory locality, which was affected by a forest fire in April 2011. For classification of the surface forest fuel we used the terrain curvature features. Totally we identified 4 basic classes of terrain morphology (ridges and valleys with a low and high curvature). For those classes we did the field survey oriented to the investigation of the forest fuel volume in t.ha-1. To quantify the surface forest fuel volume as precisely as possible we established 21 test plots in the field. Using the tools of Spatial Analyst in ArcGIS we produced the map of surface forest fuel volume distribution in the locality of Stare Hory. Results of such analyses are required as input data to the fire modeling and simulation processes in Farsite and FlamMap environments.
The Development of Composite Building Product and its Fire Technical Characteristics
Authors: Netopilová Miroslava , Mikulenka Jan , Benešová Anna
Published: August 2014

The article focuses on the research and development of a new composite material applicable in building industry, renewable raw material resources and industrial waste materials. The aim of the research is not only the application of concrete secondary raw materials but also the gaining of required safety aspects of these composite materials, i.e. certain fire technical characteristics.
Tool for Minimizing Duplicate Actions in the Activities of Safety
Authors: Holubová Věra
Published: August 2014

Safety is a part of the process of the organization management, which gets increasingly the multidisciplinary and interdisciplinary nature, due to what the process of the organization management is perceived as a solution to a complex problem. An integrated approach to the management process as a comprehensive and cross-sectional view of management issues in the organization is the way and manner of addressing the safety issue and its economy [1]. The tool for minimizing duplicate actions in the activities of safety is first precondition how to begin addressing the safety in organization effectively. It is a sequence of mutually consecutively interconnected steps whose aim is to detect, name and minimize duplicate actions in the activities of safety.
A Review on the Glass Transition of Polymer on Surface and in the Thin Film
Authors: Huang Ran
Published: August 2014

Since the first paper by Keddie et al. published on 1994 [21], the glass transition of polymer systems on surface/thin film has been an active research field and attracted many groups interests. Numerous works have been done, in both experimental and computation approaches, to investigate this subject. In this paper we reviewed the milestone findings in the last twenty years. Generally with only minor disagreements in the mechanism all the mainstream works are consistent in the conclusions that: 1) Geometric confinement in thin film or on surface reduces the glass transition temperatureTgcomparing to the bulk behavior; 2) For supported film the substrate-film interaction is critical and its effect may surpass the geometry effects and rise increase onTg; 3) Chain mobility and molecular weight are critical but the detailed phenomena vary with systems. Notwithstanding the achievement has been made, due to the controversy of glass transition itself and technology limitation on characterization on glass transitions on thin film, the research in this field is still a long-marching effort and breakthrough findings are expected for the development in materials science and engineering and feedback knowledge to understand the glass transition on the theoretical base.