bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimal Energy Storage Sizing for Wind Power Applications
Authors: Han Cong Ying , Kong Rui Yuan , Guo Tian De , Pei Wei
Published: December 2014

Wind energy is now widely used in many countries as a clean energy. In order to make better use of wind energy, we need to study various factors affecting the utilization of wind energy. If we can better predict the wind, we can make full use of wind energy. Where, combing an energy storage system with a wind farm is an effective way to mitigate fluctuations and improve the predictability of wind power. Energy storage sizing has been an important part in wind farm planning. This paper presents an optimization model for determining the capacity of a lead-acid battery integrated with a wind farm. The energy storage capacity calculated in the model gives the lowest cost and has a significant impact on remedying the prediction error. Besides, the charge and discharge operation can also be displayed in our model.
A Clean Energy Generation System of In-Tandem Combinations Each of Heat Pump, Compressor and Turbine in Wind Tunnel
Authors: Feng Yee Chang
Published: December 2014

This is a series of in-tandem combinations each of heat pump, air compressor, and air turbine disposed in a wind tunnel, working together to generate clean/renewable electricity. The air compressor, located at downstream of the preceding air turbine, extracts air from this turbine thus reduces its backpressure and causes pressure drop at the turbine exit. Turbine output work Wtb is proportional to temperature difference (T3-T4) of turbine inlet/outlet air, which varies exponentially with turbine outlet/inlet air pressure ratio P4/P3 in adiabatic process as below: Wtb = MCp (T3-T4) = MCpT3{1-P4/P3(1-1/k)} as T4=T3(P4/P3)(1-1/k) where, M=mass flow rate of air; Cp&Cv=constant pressure/volume specific heat capacities of air; k= Cp/Cv=1.4. An ASME paper [1] verifies that a suction blower put at turbine exit reducing back pressure of 200 mbar can increase turbine inlet/outlet air pressure ratio P3/P4by 25%. Therefore, Wtb becomes more than those turbines without such blowers as (T3-T4) becomes larger, thus this unique Clean Energy Generation System of Heat Pumps, Compressors, and Turbines (HPCT system) achieves producing net useful electric power. In HPCT system, each air compressor works efficiently to reduce air pressure at preceding turbine outlet, as it extracts more air from the turbine than the blower mentioned in the ASME paper, because compressors have higher compression ratio than blowers. Thus, such feature gives higher turbine pressure ratio to each combination of HPCT system than those turbines without blowers (or compressors) to reduce back pressure at turbine exit. Therefore, HPCT system of higher turbine air pressure ratio P3/P4 achieves producing more turbine output work, as air temperature at turbine exit simultaneously drops more when P3/P4 becomes larger. Heat pump is an efficient device to move heat from low-temperature source to high-temperature sink, and geothermal heat source is preferable as it provides steady and warmer heat energy. This “moved” heat is used to heat up the air in wind tunnel to offset the energy extracted by turbine from HPCT system. Also, HPCT system is fully thermally insulated, thus theoretically being of zero heat loss, as it works adiabatically. P-V&T-S curves and performance of each combination of HPCT system working cycle are studied to compare it with actual gas turbine cycle and ideal Brayton cycle. Working examples of HPCT system are presented to simulate practical applications of HPCT system, and find out virtual net useful output work and energy efficiency. HPCT system is a “COLD” Engine of Zero Carbon Emission, works under moderate energy efficiency and with higher energy density than most existing renewable energy generation systems. More importantly, it is a simply designed system using only conventional knowledge, and can be made by the existing technology under the least investment risk.
Enzymatic Esterification of Oleic Acid and Propanol by Novozym 435
Authors: Mulalee Sawittree , Sena Karnjana , Phisalaphong Muenduen
Published: December 2014

Recently, demand of biolubricants has been continuously increased since it is environmentally friendly and renewable. Therefore, this research focused on the biolubricants production from enzymatic esterification of oleic acid and propanol using Novozym 435 as a biocatalyst. The esterification experiments were conducted under the optimal conditions, as follows: 45°C, oleic acid to propanol molar ratio of 1:2, Novozym 435 loading of 5% based on the weight of oleic acid. It was shown that the optimal rotation speed at 250 rpm could minimize the effect of external mass transfer limitations and maintained the enzyme activity. The conversion of oleic acid from the esterification for 6 h with isopropanol was 76.4%, which was lower than that with n-propanol (88.9%). Novozym 435 could be reused in the production of propyloleate for at least 5 cycles with maintaining FFA conversion of 94% of its initial value. Moreover, the use of molecular sieve to remove water during the reaction could significantly enhance the final FFA conversion from 88.9% to 94.7%.
Utilization of Energy Storage to Buffer PV Output during Cloud Transients
Authors: Moumouni Yacouba , Boehm Robert F.
Published: December 2014

Consideration of the use of the major types of energy storage is attempted in this paper to mitigate the effects of power transients associated with grid-tied CPV systems due to fast-moving cloud coverage. The approach presented is to buffer intermittency of CPV output power with an energy storage device (used batteries) purchased cheaply from EV owners or battery leasers. When the CPV is connected to the grid with the proper energy storage (54kW), the main goal is to smooth out the intermittent solar power and fluctuant load of the grid with a convenient control strategy. Actual summer 2011 data collected at the Center for Energy Research (CER), UNLV are utilized for the purpose of this study. Hence, appropriate simulations have proven that not only the unit ( Amonix 7700) is capable of putting onto the grid during the day time a constant amount of power (20kW), but also is able to shift the less valuable off-peak electricity to the on-peak time (1pm to 7pm), where the electricity price is much better.
Analysis of Research Trends of Organic Solar Cell Using Patent Information
Authors: Kwon Young Il , Jeong Dae Hyun
Published: December 2014

For an efficient solution in the organic solar cell, the requirements may be largely as follows: development of organic semi-conductor material with a low energy band gap, enhancement of efficiency through morphology and surface control and an increase in efficiency utilizing tandem cell and plasmon technology. This study analyzed research trends in these three fields through a network analysis and mapping analysis using thesis information and patent information. It was shown that in case of the enhancement of efficiency through the development of semi-conductor material with an energy band gap on organic solar cell, morphology and surface control, there have been many ongoing studies since 2007. The enhancement technology for efficient utilization of tandem cell and plasmon technology has been frequently studied recently.
Impact of Powder Metallurgy Electrode in Electric Discharge Machining of H-13 Steel
Authors: Brar Gurinder Singh , Mittal Gaurav
Published: December 2014

Electric discharge machining (EDM) widely used mostly in the tool and die industry and the material normally used as electrode are copper, tungsten, graphite, copper tungsten and copper chromium alloys. In the present work, Electric discharge machining was carried on H-13 workpiece using powder metallurgy electrodes of copper chromium (CuCr) and conventional copper electrode. The input parameters selected in the study were current, voltage, duty cycle and retract distance. The output parameters were material removal rate, tool wear rate, surface roughness and overcut. Experimental results show that CuCr powder metallurgy electrode gives best results for MRR. Also CuCr powder metallurgy electrodes gives better results for overcut as compare to conventional copper electrode. It has been seen that electrode type is significant factor for all output parameters.
Speed Sensorless Control with ANN-MRAS Based on Modified ACO for Induction Motor Drives
Authors: Xu Kai , Li He Lin , Liu Shan Chao
Published: December 2014

In the speed sensorless induction motor drives system, Model Reference Adaptive System (MRAS) is the most common strategy. It suffers from parameter sensitivity and flux pure integration problems which may cause DC drift. As a result, it leads to the deterioration of estimation at low speed. To overcome these problems, an Artificial Neural Networks (ANN) is presented as a Rotor Flux (RF) observer to replace the conventional voltage model used in RF-MRAS speed observer. Simultaneously, in order to solve the trap of local minimum value of algorithm, and enhance the ANN convergence speed, we used the modified Ant Colony Optimization (ACO) to optimize the weights and thresholds value of neural networks. The results of the simulation show that, by this method, the speed of motor can be identified accurately in different situations, and the result is reliable.
Distributed Cross-Direction Control System Based on CAN-Bus
Authors: Shi Xian Cheng , Feng Yu Cheng , Zeng Jin Song , Chen Ke Fu
Published: December 2014

A distributed cross-direction control system based on CAN-bus was designed to solve the large-scale cross-direction control problem for paper machine. Multiple Master-Slave CAN networks were constructed in parallel to coordinate and control multiple array actuators, and the Ethernet/CAN converter was used to connect the monitoring station with the field intelligent actuators. The monitoring station accesses measured data and field data via OPC technology. A CAN application layer protocol and corresponding underlying communication software were designed according to the characteristics of the cross-direction control processes. Finally, the feasibility and reliability of the system were verified with practical applications.
Design and Application of Hotel Intelligent Control System
Authors: Zhang Zhen Hai , Zhou Wang Fa
Published: December 2014

Aiming at the energy waste problem in the modern hotel, hotel intelligent control system applied the PAC, internet communication, touch screen and on-scene communication technology, combined with human-based management mode. Practices substantiate that the system is safe and reliable, presenting good man-machine interactivity, reducing the energy consumption and costs, improving the market competitiveness of the hotel.Modern hotel should the clean production, energy resources’ saving, which is also an important step of environment protection that has been repeatedly asserted. Hotel is a typical representative as for energy consumption. It is estimated that the power consumption in a medium-sized (300 rooms) star hotel open for business, runs up to 500 to 700 KWH annually [1]. Therefore, it is of great significance to promote energy conservation in hotel. "Intelligent hotel energy conservation and environmental protection control system" is built around the concept of energy-saving and consumption reducing. Meanwhile, it surrounds three themes: utilization of new energy, energy efficiency, environment protection. It cherishes an comprehensive modern facility, which include central air-conditioning, boilers, water cycle, lights, intelligent garage and all the installation deserved. Its study is a prospective and practical one.
A Novel Traction Control Strategy Based on Optimal Slip Ratio Control for Electric Vehicle
Authors: Wu Ling Fei , Wang Li Fang , Zhang Jun Zhi
Published: December 2014

A novel traction control strategy based on slip ratio gradient PID control is proposed. The gradient of slip ratio can be controlled accurately through adapting the driving torque by analyzing the dynamic process of the wheel. The optimal slip ratio for traction control is found through the analysis of the characteristic of the tire. The slip ratio of the driving wheels can be control at the optimal point through slip ratio gradient PID control. An electric vehicle model for simulation based on MATLAB/SIMULINK has been built and simulations have been carried out. A hardware-in-loop test bench has been built and experiment has been carried out. Results show that the strategy can achieve better driving performance than motor torque PID control strategy.
Consensus Problem of Multivehicle Formation Using Nearest Neighbor Rule with Addition of State Buffer
Authors: Amin Umm E , Guo Shu Li , Han Li Na
Published: December 2014

We consider the problem of cooperation among a collection of vehicles performing a shared task using intervehicle communication to coordinate their actions. Tools from algebraic graph theory prove useful in modeling the communication network and relating its topology to formation stability. We show that agents can reach consensus if the value of the function is time invariant and we prove our result by taking agents initial state values. The concept of state buffer is also introduced to avoid delays in achieving consensus.
Recycled Cigarette Filter as Reinforcing Filler for Natural Rubber
Authors: Lai Mun Kou , Teo Hiu Hong , Lee Jien Ye
Published: December 2014

Natural rubber is highly resilient and possesses many outstanding characteristics but inferior in aspects like modulus and hardness. This however can be improved by reinforcement, forming a composite. The rubber compound in this study was prepared according to the ASTM D3184 standards and reinforced using cellulose acetate (CA) from recycled cigarette filter, partly as an effort to reduce the amount of waste. Moreover, cigarette filter is highly toxic due to the nicotine content thus requires care when is recycled. From the rheological and mechanical testing conducted i.e. scorch and cure time, torque, tensile test and tear strength, it seems to indicate a small amount of up 4 phr (parts per hundred rubber) of CA, is beneficial in improving the properties of the rubber compound.
Manufacturing Method of Increasing Hollow Steel Shaft Thickness Using Uniaxial Pressing
Authors: Dohi Masahiro , Kamiyama Hirotaka , Nishida Shin-Ichi , Kotani Yuji , Watari Hisaki
Published: December 2014

In manufacturing car components, the hollow parts manufacturing method is useful for reducing the product weight, especially in drivetrain parts such as long shafts. Long, hollow shafts should have middle portions with large diameters and thin walls and end portions with small diameters and thick walls in order to reduce weight while maintaining pipe strength.Generally, such long shaft parts are manufactured by reducing the end portion of the pipes with the equivalent diameter and desired hollow part thickness for the middle portion of the parts. It is difficult for manufacturers to successfully thicken the pipe wall locally by press forming because pipes buckle easily during the process. Using thick pipe is one way to prevent buckling, but when using thick pipes, we could not reduce weight much. Automotive industries have desired a manufacturing process that can reduce pipes (relatively thin pipes) without buckling.This paper clarifies the relationships among the forming conditions and the thickening ratio (thickness after forming / thickness before forming) in uniaxial press forming by experiments and finite-element simulation. Steel pipes with 39.0mm outer diameter and 7.6mm thickness were used in the experiment. The relationship between the thickening ratio and the forming load that depends on the die shape, lubrication, and slide motion of the press machine was investigated. An appropriate manufacturing condition that could reduce pipes without buckling was obtained. We clarified that the pipe wall thickness could be increased ten percent. The details of material flows in reducing pipes without buckling were discussed using finite-element simulation.
Electrospray Coating of a TiO2 Electrode for Dye-Sensitized Solar Cells by a Post-Treatment Method
Authors: Kim Jeong Hwa , Sung Shi Joon , Hwang Dae Kue
Published: December 2014

A mesoporous TiO2photo-electrode for dye-sensitized solar cells (DSSCs) was fabricated by an electrospray method using a solution of dispersed TiO2nanocrystals (P25). A mesoporous TiO2disk has a larger surface area than P25. The sub micrometer-sized TiO2disk promotes light scattering, thereby increasing the photocurrent conversion efficiency. However, the electrosprayed TiO2electrodes have many pores and disconnected electron pathways. Thus, we investigated the enhanced electrical contact of an electrosprayed TiO2electrode using a hot-pressing process and a titanium tetrachloride (TiCl4) treatment process. After optimizing the post-treatment process of an electrosprayed TiO2electrode, the cell shows conversion efficiency up to 6% at standard sunlight of AM 1.5.
Quantitative Characterization of Sulfide Corrosion Reaction in Transformer Oil
Authors: Lian Hong Song , Zheng Dong Sheng , Yan Jiang Yan , Li Qing Min , Zhou Yong , Wang Zhao Dong , Li Cheng Rong
Published: December 2014

This paper discusses the quantitative characterization of Cu-Sulfide reaction in transformer oil. Accelerated aging tests are carried on both the corrosive and noncorrosive oil samples, and by analyzing the characteristics, such as sulfur concentration, weight of the oil, degree of polymerization (DP), quantitative characterization of the Cu-sulfide deposition is established.
Continuous Transesterification for Ethyl Ester Production from Refined Palm Oil through Static Mixer
Authors: Wijitsopa Kichaphum , Somnuk Krit , Theppaya Thanansak , Prateepchaikul Gumpon
Published: December 2014

In this study, the commercial grade of ethanol was used to produce the biodiesel from refined palm oil (RPO) through the continuous static mixer system. The ethanol, an alternative alcohol to adopt in the ethyl ester production, can be used instead of methanol, and this alcohol is more eco-friendly than methanol. The 6-meter in length of SUS304 static mixer reactor is an essential part of mixing the RPO and solution of ethanol and potassium hydroxide to accelerate the base-catalyzed transesterification. The ethanol were varied at the volumetric flow rate of 30, 40, 50, 60 vol.%, KOH as base-catalyst was varied with the weight to volume of oil of 10,12,14 gKOH.L-1, to investigate the suitable condition which can converted the glycerides to the maximum purity of ethyl ester. The results showed that all varied conditions, the ethyl ester conversion was rapidly increased from 0 to over 95 wt.% when the flowing mixtures flowed through the 1 meter of static mixer. Furthermore, the highest purity of ethyl ester from RPO was succeeded when the condition: the 60 vol.% ethanol, the 14 gKOH.L-1of catalyst, 5-meter of static mixer, and 75 oC temperature of RPO, was used in the continuous static mixer.
Design of a Novice Hydraulic Buoyant Force Engine
Authors: Mir-Nasiri N. , Almenov B.
Published: December 2014

In connection with the consumptive depletion of the earth and the destructive effect of emissions of combustion products on the environment, now all of humanity is in search for alternative energy sources. The proposed technology intends to produce electricity directly at the consumer location or in close vicinity to it by utilizing the concept of vertical buoyancy power generation in a still water reservoir and thus able to lower the cost of electricity and save the fossil fuels. The newly invented machine is able to converts the buoyance force energy into mechanical energy of shaft rotation, and thus into the electricity via rotary generator. The hydraulic buoyant force engine system includes two cylindrical pulleys with belt transmission mounted on the stationary frame that is submerged into the water. The belt carries the chain of elastic plastic airbags to generate the buoyance force. The empty and weightless airbags are driven first by the belt and pulleys system to the bottom of a water reservoir where they are filled with the air delivered by the compressor and then the bulged bags and thus connected belt are driven up by the buoyant force. As a result the belt and shaft of the connected to the upper pulley generator will be constantly driven by the buoyant force. The paper describes the details of the engine construction, the amount of power generated by the engine as a function of the reservoir depth and the power of an air compressor as well as advantages of such engine installations and their impact on the society.
2k-H Planetary Gear Transmission System and its Largest Lyapunov Exponent
Authors: Liu Jin Lei , Guo Shu Li , Han Li Na
Published: December 2014

The nonlinear dynamic differential equation of 2K-H planetary gear transmission, which takes into consideration of clearance, is presented in this paper. Various Chaotic characteristics of the system are collected, such as the Largest Lyapunov Exponent and the phase locus. Experimental simulation is carried out and the periodic movement, quasi periodic movement and chaotic movement of the system are gotten under different parameters.
Design of Semi-Active Roller Guides for High Speed Elevators
Authors: Monge Raúl , Rodríguez-Fortún José Manuel , Gómez Alfredo , Roig José Alberto , González Pedro
Published: December 2014

Comfort is an important topic in the elevator industry, and among the different factors which affect it, vibration in the car is one of the most important. Passengers not only perceive this phenomenon as an unpleasant effect, but also as a signal of the elevator safety level, and therefore it is of great importance to mitigate it. Although mature technologies are available for reducing vibration in low speed elevators, the increased number of high buildings and sky-scrappers, forces the development of new technologies for medium and high speed elevators. Active vibration control techniques are widespread used for damping vibration in different industrial environments, but their application to the elevator industry normally imply expensive solutions, with bulky and heavy actuators which highly burden its application. As alternative, the cheaper and lighter semi-active vibration systems based on passive elements capable of modifying their properties in response to external commands represent an appealing option. In this paper, we describe a design method for a semi-active roller guide based on a commercial magneto-rheological damper. Different control strategies based on low cost acceleration sensors are also analyzed.
Phase Characterization in Experimental Chaotic Systems
Authors: Follmann R. , Rosa E. , Macau E.E.N. , Piqueira J.R.C.
Published: December 2014

In this work we present and discuss a method for measuring the phase of chaotic systems. This method has as input a scalar time series and operates by estimating a fundamental frequency for short segments, or windows, along the whole extension of the signal. It minimizes the mean square error of fitting a sinusoidal function to the series segment. This approach does not require following the trajectory on the attractor, works well over a wide range of adjustable parameters, is of easy implementation, and is particularly appealing for experimental settings with single signal outputs since there is no need of attractor reconstruction. We demonstrate the applicability of this method on experimental time series obtained from two coupled Chua circuits.
Influence of Nonlinear Stiffness on the Dynamics of a Slender Elastic Beam under Torsional Oscillations
Authors: Silveira Marcos , Pontes Bento R. , Balthazar José M.
Published: December 2014

This study focuses on analysing the effects of nonlinear torsional stiffness on the dynam-ics of a slender elastic beam under torsional oscillations, which can be subject to helical buckling.The helical buckling of an elastic beam confined in a cylinder is relevant to many applications. Someexamples include oil drilling, medical cateters and even the conformation and functioning of DNAmolecules. A recent study showed that the formation of the helical configuration is a result of onlythe torsional load, confirming that there is a different path to helical buckling which is not related tothe sinusoidal buckling, stressing the importance of the geometrical behaviour of the beam. A lowdimensional model of an elastic beam under torsional oscillations is used to analyse its dynamical be-haviour with different stiffness characteristics, which are present before and after the helical buckling.Hardening and softening characteristics are present, as the effects of torsion and bending are coupled.With the use of numerical algorithms applied to nonlinear dynamics, such as bifurcation diagramsand basins of attraction, it is shown that the nonlinear stiffness can shift the bifurcations and inducechanges in the stability of the desirable and undesirable solutions. Therefore, the proper modellingof these stiffness nonlinearities seems to be important for a better understanding of the dynamicalbehaviour of such beams
Least Squares Method for Attitude Determination Using the Real Data of CBERS-2 Satellite
Authors: Silva W.R. , Kuga H.K. , Zanardi M.C. , Garcia R.V.
Published: December 2014

his work is applied to the dynamics of rotational motion of artificial satellites, that is, itsorientation (attitude) with respect to an inertial reference system. The attitude determination involvesapproaches of nonlinear estimation techniques, which knowledge is essential to the safety and controlof the satellite and payload. Here one focuses on determining the attitude of a real satellite: CBERS-2(China Brazil Earth Resources Satellite). This satellite was launched in 2003 and were controlled andoperated in turns by China (Xi’an Control Center) and Brazil (Satellite Control Center). Its orbit isnear polar sun-synchronous with an altitude of 778km, crossing Equator at 10:30am in descendingdirection, frozen perigee at 90 degrees, and providing global coverage of the world every 26 days.The attitude dynamical model is described by nonlinear equations involving the Euler angles. Theattitude sensors available are two DSS (Digital Sun Sensor), two IRES (Infra-Red Earth Sensor), andone triad of mechanical gyros. The two IRES give direct measurements of roll and pitch angles with acertain level of error. The two DSS are nonlinear functions of roll, pitch, and yaw attitude angles. Thegyros furnish the angular measurements in the body frame reference system. Gyros are very importantsensors, as they provide direct incremental angles or angular velocities. They can sense instantaneousvariations of nominal velocities. An important feature is that it allows the replacement of complexmodels (different torques acting on the space environment) by using their measurements to turn thedynamical equations into simple kinematic equations. However gyros present several sources of errorof which the drift is the most troublesome. Such drifts yield along time an accumulation of errorswhich must be accounted for in the attitude determination process. Herein one proposes to estimatethe attitude and the drift of the gyros using the Least SquaresMethod. Results show that one can reachaccuracies in attitude determination within the prescribed requirements, besides providing estimatesof the gyro drifts which can be further used to enhance the gyro error model.
Satellite Orbit Determination Using Short Arcs of GPS Data
Authors: Chiaradia Ana Paula Marins , Kuga Hélio Koiti , Masago Bruna Yukiko Pinheiro Lopes
Published: December 2014

This work is concerned with short arcs orbit determination using GPS signals. A special case of truncated arcs assuming that GPS data is only available when the satellite carrying the GPS receiver passes over a ground tracking station is presented. The behaviour of an Extended Kalman filter (EKF) in real time satellite orbit determination using short arcs of data is analysed. The algorithm is a simplified and compact model with low computational cost, and uses the EKF to estimate the state vector, composed of position and velocity components, and GPS receiver clock parameters. The algorithm may use different step-sizes between the GPS signal measurements. Its force model in the motion equations considered the perturbations as being due to the geopotential up to the 10thorder and degree of the spherical harmonics. The algorithm has been formerly qualified using raw single frequency pseudorange GPS measurements of the Topex/Poseidon (T/P) satellite, and used as reference in this work. However, the GPS data are truncated as if they had been collected by a single ground tracking station. In other words, the data are obtained only when the satellite T/P is within the viewing area of the station. The research results are presented showing the degradation of performance when compared to a full arc orbit determination.
Suppressing Chaos in a Nonideal Double-Well Oscillator Using an Based Electromechanical Damped Device
Authors: Alişverişçi G. Füsun , Bayiroğlu Hüseyin , Balthazar José Manoel , Felix Jorge Luiz Palacios
Published: December 2014

In this paper, we analyzed chaotic dynamics of an electromechanical damped Duffing oscillator coupled to a rotor. The electromechanical damped device or electromechanical vibration absorber consists of an electrical system coupled magnetically to a mechanical structure (represented by the Duffing oscillator), and that works by transferring the vibration energy of the mechanical system to the electrical system. A Duffing oscillator with double-well potential is considered. Numerical simulations results are presented to demonstrate the effectiveness of the electromechanical vibration absorber. Lyapunov exponents are numerically calculated to prove the occurrence of a chaotic vibration in the non-ideal system and the suppressing of chaotic vibration in the system using the electromechanical damped device.
Nonlinear Ball and Beam Control System Identification
Authors: Colón Diego , Bueno Átila Madureira , Andrade Yuri Smiljanic , Diniz Ivando Severino , Balthazar José Manoel
Published: December 2014

The Ball and Beam system is a common didactical experiment in control laboratories that can be used to illustrate many different closed-loop control techniques. The plant itself is subjected to many nonlinear effects, which the most common comes from the relative motion between the ball and the beam. The modeling process normally uses the lagrangean formulation. However, many other nonlinear effects, such as non-viscous friction, beam flexibility, ball slip, actuator elasticity, collisions at the end of the beam, to name a few, are present. Besides that, the system is naturally unstable. In this work, we analyze a subset of these characteristics, in which the ball rolls with slipping and the friction force between the ball and the beam is non-viscous (Coulomb friction). Also, we consider collisions at the ends of the beam, the actuator consists of a (rubber made) belt attached at the free ends of the beam and connected to a DC motor. The model becomes, with those nonlinearities, a differential inclusion system. The elastic coefficients of the belt are experimentally identified, as well as the collision coefficients. The nonlinear behavior of the system is studied and a control strategy is proposed.
Nonlinear Dynamics of Shrouded Turbine Blade System with Impact and Friction
Authors: Santhosh B. , Narayanan S. , Padmanabhan C.
Published: December 2014

Dry friction dampers are passive devices used to reduce the resonant vibration amplitudes in turbine bladed systems. In shrouded turbine blade systems, in addition to the stick- slip motion induced by dry friction during the contact state in the tangential direction, the interface also undergoes intermittent separation in the normal direction. The problem can thus be treated as a combination of impact and friction. In this work, the dynamics of dry friction damped oscillators which are representative models of dry friction damped bladed system is investigated. A one dimensional contact model which is capable of modeling the interface under constant and variable normal load is used. The steady state periodic solutions are obtained by multi - harmonic balance method (MHBM). Frequency response plots are generated for different values of normal load using the arc length continuation procedure. The MHBM solutions are validated using numerical integration. A single degree of freedom (dof) model under constant normal load with constant and variable friction coefficients, a dry friction damped two dof system under constant normal load and a two dof system under variable normal load are investigated. In the presence of variable normal load, the system shows multivalued frequency response and jump phenomenon. The optimal value of the normal load which gives minimum resonant response is also obtained.
Use of Neural Networks for Modelling of Passenger Dynamics in Airport Terminal Environment
Authors: Hlavsová Pavlína , Široký Jaromír
Published: December 2014

Neural networks are methods inspired by animals´ central nervous systems, particularly by the human brain. As one of the modern mathematics methods, neural networks have been used to solve a wide variety of both practical and theoretical tasks. The aim of this paper is to illustrate the use of neural networks for modelling of passenger dynamics in the airport terminal environment. This model could be used for passenger flow control, since for the management to be appropriate it should involve passenger dynamics prediction for effective and accurate passenger flow modelling and simulation.
A Comparative Analysis of Sustainable City Logistics among Capital Cities in the EU
Authors: Kiba-Janiak Maja
Published: December 2014

The main aim of the paper is a comparative analysis of sustainable city logistics among capital cities in the EU. In order to conduct the study the Electre III/IV method has been applied. The author has developed indicators on the basis of European statistics, national statistics of EU countries, various reports and projects. Due to the lack of data this analysis is limited to a certain extent. The Electre III/IV method allowed the author to develop the ranking of capital cities in terms of selected economic, environmental and social aspects of city logistics.
Determinants of the Road Traffic Accident Rate in Slovak Republic
Authors: Štefko Róbert , Kubák Matúš , Bačík Radovan
Published: December 2014

Traffic safety is an important topic because of serious economic burden which is linked to the problem (damage costs, health care costs, administration costs and costs resulting from loss of future output). In this paper, we model damage to property and accidents involving deaths and injuries in the Slovak Republic. Using secondary data, it was found out that accidents involving deaths and injuries, accidents caused by animals and accidents caused by speeding have a strong impact on damage to property. Interesting finding is, that number of registered drivers have a negative impact on damage to property. On the other hand, accidents caused by animals and accidents caused by speeding have a negative impact on accidents involving deaths and injuries. Moreover, expressways seriously diminish number of accidents involving deaths and injuries.
New Method for Design of Transport Infrastructure Elements
Authors: Straka Martin , Balog Michal , Bindzár Peter , Semančo Pavol , Žatkovič Erik
Published: December 2014

A trend in automotive freight has experienced rapid development in recent years. The increase of traffic intensities is closely related to the increasing demand of building elements of transport the infrastructure that will provide services to monitor traffic, inform road users and protect transport companies property and citizens who participate in the process of transportation. The current state of layout and allocation problem solving of elements of transport infrastructure is limited to the use of mathematical, multicriteria or heuristic methods. Each approach has its advantages and limitations but none of them solves same layout and allocation of a particular procedure with a specific position. System of blocks (SB) method is a method, which joints the layout and allocation into one unit, using the principles of mathematics, multicriteria, heuristic procedures and graphics simultaneously. The advantage of the proposed method is the complexity of the proposed solution, i.e. consideration of multi-criteria approach with no pre-defined positions and precise definition and the actual position of the elements in space allocation.
Disassembled Vehicle Combined Transport System
Authors: Široký Jaromír
Published: December 2014

Transport of knocked down vehicles are distributed independent export project of Škoda Auto. In addition to the modes of carriage of the individual components is very important especially division of disassembly. At the same time this paper shows possibility of packing improvements of knocked down vehicles to containers and manipulation with the containers.The modern trend is not only transition from SKD disassembly, through MKD (CKD-3) to the CKD disassembly. This complete disassembly of vehicles is the target state of automobile manufacturers who use this system for production vehicles.
Possibilities and Limitations of Electromobiles Utilization
Authors: Straka Martin , Chovan Tomáš , Bindzár Peter , Žatkovič Erik , Hricová Romana
Published: December 2014

The article is focused on the actual issues of possibilities of charging stations constructions for utilization of electromobiles. Whereas the development of the area in question is dependent on possibility to fill up the energy that drives the vehicle, it is important to determine the allocation and layout of charging points. In terms of satisfying the initial requirements of electromobilists is important opportunity to recharge an electric vehicle in places that are frequently visited and where we spend some time which is sufficient for the charging of electomobile. The current state of construction charging stations within specific sites and the Slovak Republic as such is dependent on finance, legislation, landowners, the quantity of electric cars on the market and resolution to go to these projects. Within the article is nearer remitted to the possibilities and limitations that affect locality selection and construction of charging stations for electric cars needs in Slovakia.
Modern Planning and Control and Virtual Verification of Process Continuity of a New Production Line
Authors: Božek Pavol , Kňažík Marek , Štollmann Vladimír
Published: December 2014

The paper describes one practical implementation of the Digital Factory concept – design of a new production line using modern planning method of virtual testing and control of processes. The project covered graphical facility design, detailed design of operations and material flow simulation. This case study shows facility process planning, commission and in the end finding the optimization rules and corrective actions to increase existing casting line throughput. All phases of the project were carried out using simulation software, duration of the project was 6 months. Simulation software WITNESS has been used for material flow simulation.
Optimization of Gross Margin in Outsourcing of Management of Inventory of Spare Parts of Production Equipment
Authors: Brzeziński Stanisław , Grondys Katarzyna
Published: December 2014

The subject of the paper is the presentation of the case-study of the company outsourcing the spare parts stock. As the result of the changes in the agreement between the outsourcer and the large commissioning company, the task of the outsourcing company was to standardize the margin for the individual groups of products, so far highly diversified. The research problem was to analyze the development of margins using CVA (Cash Value Added) analysis and to establish such a level of the above which will satisfy the client’s requirements and provide further employment and generating profit for the outsourcing company.
Proposal for a New Structure of Enterprise Management Concept for Processing Secondary Raw Materials - Aluminum
Authors: Hačevský Andrej , Spišák Jan
Published: December 2014

From the analysis and synthesis, which consists of a draft of structure of a new enterprise management system concept based on hierarchical balancing optimization model, results clear findings and outputs. The primary benefit is considered to be the fact, that it showed the existence and use of balancing model as a tool for effective management of the production company. This article primarily describes the use of the balance model at the analysis of the production process. HBOM can be involved in the verification process impacts of the individual reversals in the technology and economics of company, at operating in the verification plan, and verification of compliance and reality.
Organization of Mounting Division by Use of Material Flow Minimization
Authors: Fedorko Gabriel , Čujan Zdeněk
Published: December 2014

Paper is oriented to the solution of mounting device for knitting machines with nested workplace organization. The proposed solution is related to the transition from the nested organization to the effective circular workplace organization which improves the work environment and also increases the number of final products.
Financial Logistics of Small and Medium Sized Enterprises
Authors: Dankova Alena , Telus Marta
Published: December 2014

The aim of this paper is to focus on the issue of financial logistics within conditions of small and medium enterprises, especially by gaining and using of financial resources by companies in selected regions in Slovak Republic.The main idea of this paper is to define possible recommendations and ideas based on the acquired knowledge for more effective use of supporting financial systems for SMEs. The aim is to eliminate regional disparities on selected area as well as possibility of using alternative sources of financing SMEs.
Integrated Risk Management and its Influence to the Increasing of the Firm’s Value
Authors: Zuzík Jozef , Weiss Roland , Mixtaj Ladislav
Published: December 2014

Successful business subject should to manage its risks in long term and to achieve sufficient profit for covering of unexpected losses. Management of risks is process that is used in business practice for identification, management and avoiding of risks in area of business. With aim to evaluate influence of integrated risks ́ management we used method of value stream analysis. This method serves for identification of risks, resulting from wasting of sources in production or administrative processes. During research and measurement we dealt with stocking process of production lines in the frame of internal material flow. According monthly observing of process of production lines stocking we found out 5 mistakes, for which we recommended possible solution that could help to optimize searching process and eliminate mistakes, which caused losses in the company.
A Company Level Performance Measurement through the Evaluation of Production Processes Performance
Authors: Daňo Matej , Horňáková Natália , Vidová Helena , Saniuk Sebastian
Published: December 2014

The presented paper is aimed at assessing the level of performance through an industrial company endpoints indicators, in which the efficiency and performance of business processes is transformed to. The paper describes the concept of company performance based on theoretical knowledge of authors from Slovakia as well as developed economies. It also provides concrete examples of financial and non-financial indicators and informs professionals and general public with a number of additional indicators. Likewise the paper characterizes most famous concepts of measurement and management of company performance based on results of a survey which was conducted by the Institute of Industrial Engineering and Management MTF STU in Trnava, as a part of the research project VEGA No. 1/0787 / 12th. Authors attach great importance to measure the process performance as an important part of performance measurement of an industrial company. They introduce the procedures for measuring the manufacturing processes, whole range of specific performance indicators of production processes as well as different methods of measuring the performance of production processes and the company as a whole unit. The level of significance is designed for each proposed indicator and measurement result consists of value reflecting the overall company performance (various departments), which can be used as a benchmark for individual departments or plants within a particular multinational group.
Methodics to Create Effective Inventory Management System in a Company
Authors: Hart Martin , Musil Miroslav , Taraba Pavel
Published: December 2014

Pursuant to the statistics data of Eurostat, the economy of European Union is slowly recovering from year lasting recession. The gross domestic product volume increased in 2nd quarter of the year 2013 by 0.3%. The industrial companies in EU are nevertheless facing still increasing competitiveness as the European and global markets are developing under current business conditions. To be successful within the frame of current supply chains the companies must have well-developed logistics management systems to effectively treat with flows streaming in their inner or outer supply chains. One of the main elements of company logistics management systems is inventory management subsystem to plan, to manage and to control particular stock items. In the paper it is briefly described the methodics to design effective inventory management system whether in industrial or service company.
Improving Accuracy of the Numerical Model Forecasting Commodity Prices
Authors: Lascsáková Marcela
Published: December 2014

In mathematical models, for forecasting prices on commodity exchanges different mathematical methods are used. In the paper the numerical model based on the exponential approximation of commodity stock exchanges was derived. The price prognoses of aluminium on the London Metal Exchange were determined as numerical solution of the Cauchy initial problem for the 1st order ordinary differential equation. To make the numerical model more accurate the idea of the modification of the initial condition value by the stock exchange was realized. The derived numerical model was observed to determine the influence of the decreased size of the limiting value error causing the modification of the initial condition value by the chosen stock exchange on the accuracy of the obtained prognoses. The advantage of the chosen sizes of the limiting value error 7 % and 8 % within different movements of aluminium prices was studied.
Analysis of Possible Failures and its Application in Complex Determination of their Consequences
Authors: Cujan Zdenek , Fedorko Gabriel
Published: December 2014

Industrial and commercial risks associated with the production, supply and commercialization of products and services provided by enterprise have effect not only on the enterprise run and its profitability, but in the extreme cause also on the viability and by that on the future of entire enterprise. Risk conditions create an assumption of enterprise crises which must be prevented.
System Design of Manual Picking of Goods in Small Trade-Distribution Company with the Importance on the Volume of Transported Goods
Authors: Martinčková Jana , Malindžák Dušan
Published: December 2014

The article deals with a system design of manual order picking of goods in small trade-distribution company in which the volume of picking and transported goods is important instead of its total weight. The main part of the paper is to select the correct type and number of passive means of transport (paper or plastic boxes, crates, etc.) for small and lightweight goods and to determine the exact order and sequence of storage-packaging goods in accordance with pre-established terms and conditions. At the end, this proposed system is applied on an example.