Volume 4, No. 12 (2006)
Articles
STEPPER MOTOR DRIVER USING USB MODULE
POPA SORIN
In this paper I present the new USB module that can be used to command and control the function of different equipments. To exemplify that work, I create an experimental device with a stepper motor. A software program written in Visual Basic makes the command of this stepper motor driver.
ALGORITHM FOR EXERGY EFFICIENCY OF PAPER MACHINE
HAZI ANETA, HAZI GHEORGHE
In this paper are presented an algorithm and software for exergy efficiency of paper machine. The algorithm contains exergy balance equation and cost balance. The thermal cost is established depending on exergy losses and exergetic efficiency of paper drying process and steam-air heat exchangers. Finally, it is presented the influence of exergy efficiency about paper cost for a paper mill in a company.
TASK ALLOCATION SYSTEM BASED ON CONTRACT NET PROTOCOL
LEON FLORIN, CROITORU ALINA-NICOLETA
In an environment with limited resources, the agents must coordinate their activity with the others in order to follow their own interests or to satisfy the group objectives. The actions of agents in a multiagent system must be coordinated because dependencies exist between agent actions, because global constraints must be respected, and no agent has the capability, resources or information needed to reach its goal within the system. Therefore, it is necessary for the agents to cooperate and coordinate their actions in order to properly use the system resources. In this paper, we present a simulation of a multiagent system used for task allocation through contract nets, in a situated environment. The evolution of the system is analyzed concerning resources and agent capabilities, as well as the rate of task solving.
DESIGN OF DIGITAL ASYNCHRONOUS SEQUENTIAL SYSTEM USING PULSE MODE AND LEVEL SIGNALS INPUTS
TIMIS MIHAI, VALACHI ALEXANDRU
In this paper we propose to present the pulse mode asynchronous sequential systems implementation method. On the system input we have digital level input signals and pulses signals inputs. During the pulses inputs are generated, the digital level input signal must remain constant ( 1 or 0). If it changes it's value during the pulses occurrences, the system may fail. To generate de pulses signals we use relays switchers.The proposed algorithm can be successfully implemented in vending machines automata.
DESIGN OF DIGITAL ASYNCHRONOUS SEQUENTIAL SYSTEM USING ONLY PULSE MODE INPUTS
TIMIS MIHAI, VALACHI ALEXANDRU
In this paper we propose to present the pulse mode asynchronous sequential systems implementation method. On the system input we have digital level input signals and pulses signals inputs. During the pulses inputs are generated, the digital level input signal must remain constant ( 1 or 0). If it changes it's value during the pulses occurrences, the system may fail. To generate de pulses signals we use relays switchers. The proposed algorithm can be successfully implemented in vending machines automata.
ECOLOGICAL ANALYSIS OF THE TROTUS BASIN (CASE STUDY BACAU COUNTY)
BERCA MIHAI, STOICA MARICICA
The authors analyze the causes which generated the disastrous events in the summer of year 2005 in the hydrographic basin of the Trotus River, stressing those generated by ecological dysfunctions, due to the brutal intervention of people through extensive deforestation of the slopes of the Trotus River's tributaries and of the mountainous area the river flows through in Bacau County.
VIRTUAL INSTRUMENT FOR HARMONIC ANALYSIS
ABABEI ŞTEFAN
Harmonic analysis of periodic signal is a major importance for determining the energy quality. This paper, presents a virtual apparatus for frequency analysis of periodic signals. The virtual apparatus use a NI 6221 DAQ module to acquire the periodic signal. The soft for the virtual apparatus is realized in LabView programming medium. The panel and diagram windows of apparatus are presented.
CONSIDERATIONS ABOUT APPLICATION OF ADAPTIVE FAULT DETECTION SCHEMES TO A POWER PLANT
BADEA ADRIAN, GRIGORE ROXANA
In this paper are presented theoretical results regarding the design of an adaptive fault detection scheme. The issue of robustly detecting system faults in the presence of modeling errors is also addressed. It is presented the importance of application of adaptive detection scheme to a power plant.
TELECOMMUNICATIONS AND EXPERT SYSTEMS
BĂLĂŞOIU LEONARD
Telecommunications is one of the most rapidly growing industries worldwide. In developing countries, there is a huge market to offer both wireline and wireless telephone services. The majority of people there simply do not have the basic telephone service. Many of these countries have started to privatize their telephone industry. In the developed countries such as the Romania, the explosion of Internet usage and the growth of personal computers are forcing telecommunications companies to expand the facility to offer both data and voice services. As the deregulation of the telephone industry gradually opens up the Romania market for competition, telecommunications companies here will rely on advanced technologies for competitive leverage. One such technology is the expert system technology that enables telecommunications companies to offer improved products and services at low cost. Expert systems in this context are computer programs that emulate the behavior of telecommunications experts and automate the operation of telecommunications systems using artificial intelligence techniques.
GENETIC ALGORITMS - CASE STUDY: AVILABILITY-COST OPTIMIZATION OF ALL-OPTICAL NETWORK
BALAŞOIU LEONARD, PRUTEANU EUSEBIU
Abtract: Many of design problems in telecommunications could be treated as optimization problems that include some kind of searching among a set of potential solutions. The choice of the method depends mostly on the problem complexity. If the number of possible solutions is not too big, one could enumerate them all, evaluate their goal functions, and select the best solution(s). If the function to be optimized is done by a derivative continuous function, analytical methods could be applied. In all other cases, where the problem space is too big and analytical methods are not applicable, some sort of heuristic search for optimal solution could be applied. Genetic algorithms, could be classified as guided random search evolution algorithms that use probability to guide their search. Genetic algorithms are created by analogy with the processes in the reproduction of biological organisms. By natural selection or by forced selection in laboratories, new generations of organisms are produced. As a consequence of crossover and mutation processes on chromosomes and genes, the children could possess either better or worse features than their parents. The "better" organisms are those that have a greater chance than the "worse" ones to survive and to produce a new generation.
TRAKING CONTROLLER FOR PHOTOVOLTAIC SYSTEMS BASED OF NEURAL NETWORKS
CULEA GEORGE, POPESCU CORNEL, ABABEI ŞTEFAN
The power delivered by photovoltaic systems it can be increased through its automated tracking after the sun. Utilizing a cheap solution for control required the implementation of an algorithm for orientation, simple and efficient. The best solution was the classic algorithm that generates sun relative movement from Terra. Because the calculus volume of sun position is relative big, it must be necessary to find another solution that described the sun trajectory. The proposed solution it based on a neuronal structure, capable to approximate with a good precision the sun trajectory and to deliver permanently its coordinates.
THE IMPORTANCE OF MODEL BASED DIAGNOSIS APPLICATION TO POWER PLANTS
GRIGORE ROXANA, ABABEI ŞTEFAN
An on-line process monitoring system is essential to be an integral part of any power plant control system. Model-based methods of fault detection were developed by using input and output signals and applying dynamic process models. The task is to generate symptoms indicating the difference between nominal and faulty status. It will follow fault diagnosis procedures, determining the fault.
DETERMINATION OF VOLTAGE TRANSFORMERS STATE FROM SUBSTATIONS USING STATISTICAL PROCESSING OF EXPLOITATION DATA
HAZI GHEORGHE, HAZI ANETA
This paper analyses possibility for obtaining of synthetic information about voltage transformers from substations, using statistical processing of current exploitation data: incidents recorded, results of measures and of tests, derogations, periodically maintenance. Thus, determination of extreme value, of mean value and of square mean deviation can lead to significant conclusions from view point of exploitation activity policy. There are presented results obtained for current transformers in the 400/220/110 kV substations from Moldova.
CONTROL SYSTEM FOR STARTING UP THE D.C. MOTORS WITH SEPARATE FIEL
LIVINŢI PETRU
This work is presenting a control system for starting up the D.C. motors with separate excitation, built in both wired and programmed logic. The electrical control diagram in programmed logic was performed by means of a programmable logical controller (PLC), TWIDO type, produced by Schneider. Through the usage of the TWIDO PLC a control system with better functioning performances is obtained, compared to the wired logic control system.
USING AN HYBRID INTELLIGENT SYSTEM, MULTIPLE NEURAL NETWORK AND GIS FOR PROTECTING WATER SUPPLY QUALITY
PRUTEANU EUSEBIU, ABABEI ŞTEFAN
The rapid growth in the number and variety of applications of the fuzzy logic controller and neural networks reflects the advantages of the intelligent techniques applications. Neuro-fuzzy modeling is aimed at solving real world decision making, modeling and control system problems, witch are usually imprecisely designed and require human operator intervention. In this paper neuro-fuzzy method with their ability to incorporate human knowledge are used in the conception and design of hybrid intelligent systems and models. Implementation of the neuro-fuzzy models and algorithms by using the weighting sums method is proposed
POWER SYSTEMS, SUCH AS LOAD FORECASTING, FAULT DIAGNOSIS, ALARM HANDLING AND STATE ESTIMATION WITH MULTIPLE NEURAL NETWORK
PRUTEANU EUSEBIU, NIŢU COSTICĂ, ENESCU ALEXANDRU
Artificial Neural Networks proved to be capable of finding internal representations of interdependencies within row data not explicitly given or even known by human experts. This typical characteristic together with the simplicity of building and training Neural Networks and their very short prediction delay time encourages researchers to apply neural networks to different tasks for power systems, such as load forecasting, fault diagnosis, alarm handling and state estimation. By combining more than one of these neural networks, better performance can be achieved with these new architectures.
FUZZY LOGIC IN EMBEDDED MICROCOMPUTERS AND CONTROL SYSTEMS. HARDWARE CONSIDERATIONS
ROTAR DAN
The computing or controlling elements of embedded control applications are embedded inside the application. The embedded control systems with PIC microcontroller are discussed. The PIC microcontroller family is presented and the fuzzy logic main resources are analyzed. The fuzzy logic technique implies specific hardware configurations for the input variables and the main author solutions are presented.
FUZZY LOGIC IN EMBEDDED MICROCOMPUTERS AND CONTROL SYSTEMS. SOFTWARE CONSIDERATIONS
ROTAR DAN
Fuzzy logic control can be used to implement a wide variety of intelligent functions including everything from consumer electronic goods and household appliances to auto electronics, process control, and automation. The paper presents the mains tools used for PIC microcontroller programming. The software techniques for fuzzy software programming are presented and the main aspects of the fuzzy controller are discussed.
STUDIES CONCERNING THE USES OF ION EXCHANGERS IN FOOD INDUSTRY
ARUŞ VASILICA ALISA, JINESCU GHEORGHIŢA, NISTOR DENISA, LEONTE MIHAI
The based on ion exchange extend fast in the chemistry and technology of food products owing to special advantages tehnical-economic on which they realize. In this study are adduced the applications to the ion exchangers in some technologies from food industry (sugar, milk, juices, fats technology and in oenology). So the separation and the batching of bases and acids, of cations and anions from the food products it realizes highly easy using adequate ionic resins, chelates resins its resins with exchange selective ability and nanomaterials.
ENVIRONMENT IMPACT OF PRODUCTS AT THE END OF THEIR LIFETIME
AXINTE CRINA, CRISTEA ION
As compared to the standard design process, one of the most salient new elements in ecodesign is that manufacturers now have to start thinking about what happens with the product after it leaves the factory. Additionally, manufacturers must develop different scenarios for what happens to the product when the user no longer use it; in other words, what happens in the product end-of-life phase? This paper deals with the product end-of-life alternatives: what they are and when can be applied?
CONTRIBUTIONS REGARDING TO UTILIZATION THE PLATES OF METALLIC CARBIDES AT THE TAMPING TOOLS
BEŞLEAGĂ CR., DRAGOI D.D., BADEA S.G.
World wide using of some materials and technologies to increase the wear resistance of the active part (tine) of the tamping tools is less known and spread, one example in this case is the usage of tungsten carbides. Internal matters aren't accomplishments in this area, because it isn't information and there are a lot of difficulties.
CONSTRUCTIVE AND FUNCTIONAL GEOMETRY OF THE ACTIVE PART OF THE TAMPING TOOLS
BEŞLEAGĂ CR., DRAGOI D.D., BADEA S.G.
The theoretical researches of the tamping tool and particularly of the active part have permitted accomplishments regarding to constructive and functional geometry of active part of the tamping tools. The analyze and the study of the functional and constructive geometry of active part of the tamping tools has a great importance regarding to discover and design a new constructive geometry, which can help to obtain a new tamping tools much better for their technologically qualities or on the other hand to obtain a new functional geometry, much better regarding the exploitation of the tamping tools and the quality of the tamping operation
THE DETERMINATION OF THE RESISTANCE FORCE WHEN THE TAMPING TOOL GOING IN THE BALLAST
BEŞLEAGĂ CR., DRAGOI D.D., BADEA S.G.
The investigations in specialized literature regarding at the actual stage of the researches, design, manufacture and exploitation of the tamping tools have showed a low level of information and technical details regarding these types of tools. The theoretical researches of the tamping tool and particularly of the active part have permitted accomplishments regarding to calculation the resistance force at penetration into the ballast. Known the resistance force is necessary to designing and manufacturing of the different tamping tools for the different tamping machine.
CONSTRUCTIVE AND FUNCTIONAL GEOMETRY OF THE ACTIVE PART OF THE TAMPING TOOLS
BEŞLEAGĂ CR., DRAGOI D.D., BADEA S.G.
The theoretical researches of the tamping tool and particularly of the active part have permitted accomplishments regarding to constructive and functional geometry of active part of the tamping tools. The analyze and the study of the functional and constructive geometry of active part of the tamping tools has a great importance regarding to discover and design a new constructive geometry, which can help to obtain a new tamping tools much better for their technologically qualities or on the other hand to obtain a new functional geometry, much better regarding the exploitation of the tamping tools and the quality of the tamping operation
EFFECT ON SIMULATION LUBRICANT MODELING OF MATERIAL FORMING
CRISTEA ION, AXINTE CRINA
Solid cylinder upsetting is analyzed using three different approaches for frictional boundary condition modeling. These are constant shear friction factor, experimentally measured frictional stresses, and analytical models accounting for lubricant entrapment and redistribution. All three approaches are implemented in the CFORM finite element code. The error between the three approaches and actual experimental measurements of the material deformation and interfacial pressures is investigated. It is shown that the constant shear friction factor is more accurate for solid film lubricants than for liquid lubricants. However, the calculations indicate that if accurate prediction of near net shape forming processes is to become a reality, improvements need to be made in the characterization of frictional boundary conditions. New theoretical developments applicable to arbitrary shapes and more accurate than the constant shear friction approach are needed.
MAGNETIZATION OF AMORPHOUS STROPS OF Fe40Ni40B20 IN PERPENDICULAR NEGATIVE FIELDS
DRAGOI D.D., BEŞLEAGĂ CR., DRAGOI A., BADEA S.G.
The literature of the domain presents a series of results concerning the magnetic characteristics of hysteresis for various amorphous alloys in strop form, magnetized in unidirectional bields, but no references have been found regarding the magnetization of the strops of Fe40Ni40B20 in perpendicular magnetic fields.
THE PLASTIC DEFORMATION IN THE MECHANICAL ALLOYING OF THE AMORPHOUS ALLOYS
DRAGOI D. D., BEŞLEAGĂ CR., DRAGOI A.
The plastic deformation in the cold state generates an increase of the density, of the dislocation and this intensifies the diffusion process in the powder volume and substantially modifies the interfacial characteristics of these by creating some big concentrations of crystalline flows of the type of interstitial allows and vacancies. Knowing the fact that the mobility of the interstitial atoms is bigger than that of the vacancies, these areas can be at a certain moment suprasaturated in vacancies, which could strongly affect the diffusion process.
ELEMENTS FOR A NATIONAL POLICY PROMOTING THE BIOFUELS
STOICA MARICICA, MANEA GHEORGHE
The offensive of the biofuels on the biofuel market is strongly stimulated by ecological, economic, demographic considerations, which remain viable on long and very long term. The biomass - raw matter for biofuels is a regenerable source, alternative to the fossil resources of raw energy, which are exhaustible in time, without geopolitical implications and thus without price fluctuations, typical to the primary combustibles. The impact with the environment of the production and consume of biofuels is reduced as compared with the fossil combustibles. The important research - development potential in the whole world facilitates the large approach of all aspects regarding the culture of biomass, combustible production, car engine performances, acquirement and valorization of secondary products resulting from processing the biomass.
ECOLOGICAL RECONSTRUCTION OF RURAL HABITATS (CASE STUDY - BACÃU COUNTY)
STOICA MARICICA, BERCA MIHAI
The process of ecological reconstruction of rural habitats is a long term and flexible process, which requires, for some villages, spatial modification, with a view to their integration within the territorial ecosystems they are placed on, without creating unbalances in the functioning of these territories (without fragmenting them). Through reconstruction we must pursue to re-establish the connectivity at ecosystem(s) level on the territory the rural habitats are located and which developed chaotically by fragmenting the natural or semi natural ecosystems leading to the abatement of biodiversity, the emergence of some major unbalances whose effects are felt by means of natural disasters that have been happening throughout the county, during the last years.
ECOLOGICAL RECONSTRUCTION OF THE ECONOMIC INFRASTRUCTURE (CASE STUDY - BACAU COUNTY)
STOICA MARICICA
Ensuring the co-habitation of the main categories of ecosystems and economic infrastructure at county level requires to find development alternatives that would be "ecologically sustainable, economically viable, socially acceptable". Therefore, it is crucial that the main goal of development be the improvement of the quality of life, the selection and implementation of alternatives of sustainable development, in accordance with the opportunities and limits of natural capital. This implies to adapt and reconstruct economic infrastructure on an ecological basis, in close relation with the structure, the production and bearing capacity of the natural capital, correlating human needs with the diversity and the productive and bearing capacity of the natural capital, according to the principles of ethics and sustainable use. Implementing a change of such dimension requires infusion of capital, the commitment of authorities, managers, population, companies, new ideas in design, experimented specialists.
RESEARCHES CONCERNING THE UTILIZATION OF MICRO- AND NANO-POROUS MATERIALS BASED ON CLAYS AND ZEOLITES IN GASES DEPOLUTION
URSU ALINA, NISTOR DENISA, JINESCU GHEORGHIŢA, MIRON DORU NECULAI
This study underlines the utilisation of different micro- and nano-porous materials (clays, molecular sieves-zeolites) in depollution of industrial gases. The most commons polluted gases that results in industry are CO, CO2, SO2, NOx, VOC (volatile organic compounds), NH3 etc. Two of the most appropriate materials (low costs, good adsorption properties) that can be used in gas separation are based on different types of clays or zeolites. The major advantage of using clays and zeolites in gas separation is their potential ability for the successive regeneration and the lower temperature of reaction. This paper presents the results of the most recently studies regarding industrial gases depollution using porous materials based on clays and zeolites.