Volumul 29


29-96 INGINERUL ALEXANDRE GUSTAVE EIFFEL (1832 – 1923) Partea a II-a

L’INGENIEUR ALEXANDRE GUSTAVE EIFFEL
(1832-1923) Partie II
Cet article présente, synthétiquement, les principaux repères de la vie
et l’activité de l’ingénieur français Alexandre Gustave Eiffel, réalisateur d’une
série de structures métalliques audacieuses – ponts, viaducs, édifices – qui ont
fait sa célébrité en France et dans le monde. Auteur d’une laborieuse activité
scientifique expérimentale – étant considéré comme un des fondateurs de
l’aérodynamique – et entrepreneuriale, A. G. Eiffel est aussi le constructeur de
la Tour qui porte son nom – devenu le symbole représentatif de Paris. Cette
Tour a joué un rôle essentiel pendant la première guerre mondiale, aux débuts
de la télégraphie sans fil et, ensuite, de la télévision. Ses remarquables
accomplissements, légués en héritage à l’humanité toute entière, sont dignes
de notre profonde reconnaissance.
Mots-clés: structures métalliques, ponts, viaducs, édifices,
aérodynamique, soufflerie, contraintes, flèche, hélice, projectiles, tour
Cuvinte cheie: structuri metalice, poduri, viaducte, clădiri,
aerodinamica, restricții de tunel de vânt, săgeată, spirală, proiectile, turn

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29-95 INGINERUL ALEXANDRE GUSTAVE EIFFEL (1832 – 1923) Partea I-a

L’INGENIEUR ALEXANDRE GUSTAVE EIFFEL
(1832-1923) Partie I
Cet article présente, synthétiquement, les principaux repères de la vie
et l’activité de l’ingénieur français Alexandre Gustave Eiffel, réalisateur d’une
série de structures métalliques audacieuses – ponts, viaducs, édifices – qui ont
fait sa célébrité en France et dans le monde. Auteur d’une laborieuse activité
scientifique expérimentale – étant considéré comme un des fondateurs de
l’aérodynamique – et entrepreneuriale, A. G. Eiffel est aussi le constructeur de
la Tour qui porte son nom – devenu le symbole représentatif de Paris. Cette
Tour a joué un rôle essentiel pendant la première guerre mondiale, aux débuts
de la télégraphie sans fil et, ensuite, de la télévision. Ses remarquables
accomplissements, légués en héritage à l’humanité toute entière, sont dignes
de notre profonde reconnaissance.
Mots-clés: structures métalliques, ponts, viaducs, édifices,
aérodynamique, soufflerie, contraintes, flèche, hélice, projectiles, tour
Cuvinte cheie: structuri metalice, poduri, viaducte, clădiri,
aerodinamica, restricții de tunel de vânt, săgeată, spirală, proiectile, turn

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29-94 NICOLAI COPERNIC – PĂRINTELE ASTRONOMIEI MODERNE (TORUŃ, 1473 – FROMBORK, 1543). Partea a II-a

NICOLAI COPERNIC – LE PÈRE DE L’ASTRONOMIE
MODERNE
On présente synthétiquement les principaux repères biographiques de
la fructueuse activité de Nicolas Copernic, à commencer par ses années de
formation – à l’école et aux universités fréquentées (Cracovie, Bologne, Padoue
et Ferrare) – et en continuant avec son travail de secrétaire et médecin
personnel de l’évêque Varmien, Lukas Watzelrode – son oncle -, ainsi qu’en
tant que chanoine de la Varmie et de la Poméranie. On met en évidence la
passion pour les mathématiques et l’astronomie du jeune étudiant et, plus tard,
sa ténacité à observer le ciel, ainsi que la persévérance de ses réflexions sur la
structure réelle de l’Univers.
Par crainte de la réaction de l’Église – qui était adepte du système
ptolémaïque, géocentrique – son ouvrage capital, «De revolutionibus Orbium
Caelestium», n’a été imprimé que dans l’année de sa mort, le système
ptolémaïque, héliocentrique s’avérant être réel, produisant ainsi une véritable
révolution en astronomie, en philosophie et en toute une série d’autres
sciences. On dit qu’il a été l’homme qui «arrêta le Soleil et qui mit la Terre en
marche»!
Mots-clés: Université, astronomie, univers, Terre, Soleil, planètes,
géocentrique, héliocentrique, cosmos
Cuvinte cheie: universalitate, astronomie, Pământ, Soare, planete,
univers, geocentric, heliocentric, cosmos

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29-93 NICOLAI COPERNIC – PĂRINTELE ASTRONOMIEI MODERNE (TORUŃ, 1473 – FROMBORK, 1543). Partea I-a

NICOLAI COPERNIC – LE PÈRE DE L’ASTRONOMIE
MODERNE
On présente synthétiquement les principaux repères biographiques de
la fructueuse activité de Nicolas Copernic, à commencer par ses années de
formation – à l’école et aux universités fréquentées (Cracovie, Bologne, Padoue
et Ferrare) – et en continuant avec son travail de secrétaire et médecin
personnel de l’évêque Varmien, Lukas Watzelrode – son oncle -, ainsi qu’en
tant que chanoine de la Varmie et de la Poméranie. On met en évidence la
passion pour les mathématiques et l’astronomie du jeune étudiant et, plus tard,
sa ténacité à observer le ciel, ainsi que la persévérance de ses réflexions sur la
structure réelle de l’Univers.
Par crainte de la réaction de l’Église – qui était adepte du système
ptolémaïque, géocentrique – son ouvrage capital, «De revolutionibus Orbium
Caelestium», n’a été imprimé que dans l’année de sa mort, le système
ptolémaïque, héliocentrique s’avérant être réel, produisant ainsi une véritable
révolution en astronomie, en philosophie et en toute une série d’autres
sciences. On dit qu’il a été l’homme qui «arrêta le Soleil et qui mit la Terre en
marche»!
Mots-clés: Université, astronomie, univers, Terre, Soleil, planètes,
géocentrique, héliocentrique, cosmos
Cuvinte cheie: universalitate, astronomie, Pământ, Soare, planete,
univers, geocentric, heliocentric, cosmos

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29-92 SISTEM AUTOMAT PENTRU ÎNCERCAREA LA TRACȚIUNE A PRODUSELOR COMPOZITE DIN CAUCIUC

SYSTEME AUTOMATISE POUR L’ESSAI
DES PRODUITS COMPOSITES EN CAOUTCHOUC
On pressente une solution pour moderniser une installation d’essai des
produits en caoutchouc [8], [9].La modernisation réside essentiellement dans le
remplacement des traducteurs de force de type inductif par des cellules de
traction plus précise (cellules dynamométriques), qui offre la possibilité d’avoir
une précision plus élevée du mesurage, de renoncer aux solutions mécaniques
pour mettre en évidence la déformation de la pièce et de les remplacer avec
des règles optiques, plus précises et plus facile d’intégrer dans un système
automatisé
Mots cles: system automate, essai de produits, produits composites
Cuvinte cheie: sistem automat, încercarea produselor, produse
compozite

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29-91 CONSIDERAȚII PRIVIND INFLUENȚA VIBRAȚIILOR ALEATOARE INDUSE DE VEHICULE ȘI CALEA DE RULARE ORGANISMULUI UMAN

CONSIDERATIONS REGARDING THE INFLUENCE OF
RANDOM VIBRATIONS INDUCED BY VEHICLES
AND HUMAN BODY RACEWAY
The Comfortability of modern vehicles is one of the most important
attributes that each of buyers who want the highest possible level, increasingly
more. Comfort depends on a number of external factors (raceway, damping
system, insulation/soundproofing) and internal (air conditioning system, interior
space, comfortability seats).
Isolation of vibration of the rails and vehicle body structure is the most
important aspect in reducing the destructive effects of the spine – the main area
affected, and the degradation of the muscular system, nervous, on the go. Seat
level vibration perception is different from the front to the rear because of the
different construction and equipment.
Keywords: random vibration, body, magnetorheological damper
Cuvinte cheie: vibrații aleatoare, organismul uman, amortizor
magnetoreologic

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29-90 ANALIZA TENSIUNILOR ȘI DEFORMAȚIILOR LA ȘASIUL UNUI VAGON DE MARFĂ CU PEREȚI ÎNALȚI ÎN URMA UNOR LUCRĂRI DE REPARAȚIE ȘI CONSOLIDARE

ANALYSIS OF TENSIONS AND DEFORMATIONS TO THE
CHASSIS OF A FREIGHT WAGON WITH HIGH WALLS
AFTER CONSOLIDATION AND REPAIR WORKS
This paper checks by the finite element method the solution to
strengthen the chassis of a boxcar with high walls in the process of corrective
and predictive maintenance railway vehicles run scheduled ungass works
inspections and repairs in order to keep running optimally or improved and
increase transport capacity correlated with the life extension of the rail vehicle
Keywords: freight wagon loads, stresses, strains, maintenance
Cuvinte cheie: vagoane de marfă, sarcini, tensiuni, deformaţii,
mentenanţă

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29-89 TENSIUNI REMANENTE ȘI METODE DE DETENSIONARE A CADRELOR BOGHIURILOR VAGOANELOR DE CĂLĂTORI

RESIDUAL STRESS AND METHODS OF STRESS RELIEF
FOR COACHES BOGIE FRAMES
The study has pursued experimental determination of residual
stresses in the bogie Minden-Deutz that equips coaches Series 209, the
efficiency of the applied stress relieving treatment and the possibility to shift
towards the dimensional stabilization through vibrations.
Keywords: residual stress, bogie
Cuvinte cheie: tensiuni remanente, boghiu

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29-88 LUCRUL CU PROGRAMUL SOLIDWORKS PENTRU CALCULUL FRECVENŢEI PROPRII A UNUI CUB UTILIZÂND STUDIUL DE TIP „FRECVENŢĂ”

WORKING WITH SOLIDWORKS SOFTWARE FOR THE
CALCULATION OF NATURAL FREQUENCY OF A CUBE
USING THE „FREQUENCY” TYPE STUDY
This paper presents the work with SolidWorks software regarding the
Simulation module respectively the „Frequency” type study. This type of study will
highlight the calculation and results for the natural frequency of vibration modes for
a cube with the side of 50 mm. To see how the natural frequency values can be
change, different geometries of the same designed 3D cube will be make.
Keywords: SolidWorks software, study, natural frequencies, cube
Cuvinte cheie: programul SolidWorks, studiu, frecvenţe proprii, cub

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29-87 INFLUENȚA RIGIDITĂȚII MECANICE ASUPRA FRECVENȚELOR PROPRII DE VIBRAȚIE A CADRELOR METALICE

THE INFLUENCE OF MECHANICAL STIFFNESS ON EIGEN
FREQUENCIES OF VIBRATION AT METAL FRAMES
This paper presents a study regarding the changes of the natural
frequency of trusses due to stiffness increase. The finite element analysis was
performed, considering a constantly increasing of stiffness of frame. In this way,
the correlation between frequency changes in the transversal vibration modes
and stiffness for the studied frames is highlighted.
Keywords: stiffness, eigen frequency, vibration mode, FEM
Cuvinte cheie: rigiditate, frecvente proprii, moduri de vibraţie, MEF

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29-86 METODE DE EVIDENŢIERE A FRECVENŢELOR APROPIATE

METHODS TO HIGHLIGTH CLOSE FREQUENCY
This paper offers an overview of simpler methods to accurately
estimate frequencies. In standard signal processing, the precision of frequency
estimation increases once the frequency resolution is improved. A finer
resolution is achieved by increasing the observation time interval. If this cannot
be done, the signal length can be artificially extended through the so-called
”zero-padding” method, by adding a number of samples with null amplitude.
The methods have been tested for concrete cases, using the signal processing
tool offered by the open source software, Scilab.
Keywords: signal processing, spectral analyze, “zero-padding” method,
Scilab environment
Cuvinte cheie: procesarea semnalelor, analiza spectrală, metoda
“zero-padding”, mediul Scilab

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29-85 DIMINUAREA DEFECTELOR CE APAR ÎN PROCESUL DE FABRICAȚIE AL ROLELOR DE RULMENT

SHRINKING FAILURE OCCURRING MANUFACTURING
PROCESS OF ROLLER BEARINGS
This paper contains a brief overview of the flow of production of roller
bearings that equip radial model practiced by the firm INA/Germany. The focus
is on defects occurring in different phases that are unusable respective rolls. Is
a case study and propose a method of reducing the defects reported
Keywords: radial roller bearing, INA/Germany, polishing process
Cuvinte cheie: rulment radial cu role, INA/Germania, procedeu de
lustruire

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29-84 DEFECTE SEMNALATE LA LAGĂRELE DE ROSTOGOLIRE ÎN TIMPUL EXPLOATĂRII

FAULTS REPORTED TO CAMPS ROLLING IN SERVICE
This paper contains a brief overview of defects occurring in rolling
bearings during operation. Currently, design and manufacture various types of
bearings concerned several production units worldwide. The first three
prestigious companies in Europe are: SKF / Sweden, SNR / France and INA /
Germany. Replacing sliding bearings with roller bearings is made in the context
of the cruising speeds of vehicles grow continuously and need that from stage
design to ensure maximum safety during operation thereof by eliminating
possible defects that can occur.
Keywords: bearing, faulty operation, prestigious companies
Cuvinte cheie: rulment, defecte în exploatare, firme de prestigiu

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29-83 STUDIUL STĂRII DE TENSIUNI ŞI DEFORMAŢII CE APAR ÎN ROLELE DE RULMENT DE DIMENSIUNI MICI ÎN TIMPUL CONTACTULUI DINTRE CAPUL ROLEI ŞI GENERATOARE CÂND UNGHIUL DE IMPACT ESTE CUPRINS ÎNTRE 0° ÷ 60°

THE STUDY OF STRESS AND STRAIN OCCURRING IN
SMALL BEARING WHEELS DURING THE CONTACT
BETWEEN THE HEAD PULLEYS AND GENERATING THE
ANGLE OF IMPACT IS BETWEEN 0° ÷ 60°
The paper presents comparative way using numerical techniques for
modeling dynamic physical phenomena occurring at impact between two rolls
with a diameter of 16 mm in several distinct situations to clash head –
generating at an angle to an angle between 0° ÷ 60°. Analyzed situations occur
frequently in the manufacturing of cylindrical rollers that equip small radial
bearings.
Keywords: cylindrical roller, impact, stress, displacement
Cuvinte cheie: rolă cilindrică, impact, tensiuni, deformaţii

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29-82 STUDIUL CIOCNIRII ROLELOR DE RULMENT RADIAL PRIN METODE NUMERICE DE CALCUL

BALL BEARINGS RADIAL COLLISION STUDY
BY NUMERICAL CALCULATION
The paper shows that the wheels now fitted radial bearings collide
during the manufacturing process. As a result of this rolls surface defects occur
due to collision elastic-plastic material. For different cases of collision was
made a study on the state of stresses and strains using the Finite Element
Method.
Keywords: radial roller bearing, Elastoplast’s clash, finite element
method
Cuvinte cheie: rulment radial cu role, ciocnire elasto-plastică, metoda
elementelor finite

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29-81 REZULTATE PRELIMINARE PRIVIND STABILIREA EXPERIMENTALĂ A MĂRIMII COEFICIENTULUI DE FRECARE LA ROSTOGOLIRE

PRELIMINARY RESULTS CONCERNING ON EXPERIMENTAL
DETERMINATION OF THE ROLLING FRICTION COEFFICIENT
The authors, in their preliminary investigations [xxxx], conceived an
original testing bench, in order to establish the magnitude of the rolling friction
coefficient.
Involving the mentioned testing bench, the authors started to perform
some preliminary experimental investigations in several tribo-couples, foreseen
with thin plastic cover layer.
In the described investigations, the authors offer useful correlations
between the thickness of the layers and the magnitude of the rolling friction
coefficient.
Their next topic will consist in combining different tribo-couples, having
covered and uncovered elements, in order to diminish as soon as possible the
magnitude of the rolling friction coefficient.
One has to underline the fact that the proposed original methodology
will represent in the next period a high-accuracy approach in the evaluation of
the rolling friction coefficient, corresponding to different pairs of elements, which
constitute the tribo-couple.
Keywords: rolling friction coefficient, experimental evaluation, original
testing bench
Cuvinte cheie: coeficient de frecare la rostogolire, investigaţii
experimentale, stand original pentru teste

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29-80 CONSIDERAȚII PRIVIND REZISTENŢA LA IMPACT A PARAPETULUI DE PROTECȚIE FĂRĂ ELEMENT DE AMORTIZARE

IMPACT RESISTANCE CONSIDERATIONS OF ROAD
RESTRAINT SYSTEMS WITHOUT DAMPING ELEMENTS
The paper presents the results of experiment made using a pendulum
for road restraint systems without damping elements. Deformable parapets are
created to protect the vehicles and other participants at traffic from danger and
serious injury.
The results of the experiment are very important for the knowledge of
the type of parapets that are being used on the roads.
Keywords: shock test, road restraint systems
Cuvinte cheie: încercare la şoc, sisteme de reținere rutiere

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29-79 TESTE DE ÎNCOVOIERE ASUPRA SANDWICH-ULUI COMPOZIT DE TIP CELLITE

BEND TESTS ON CELLITE COMPOSITE SANDWICH
In this paper, three-point bend tests have been accomplished on
CELLITE composite sandwich to determine the flexural properties of this kind of
structure. Load-deflection distributions until break and at 50 mm deflection have
been carried out on a LR5K PLUS Lloyd’s Instruments materials testing
machine using the NEXYGEN PLUS software.
Keywords: test bending, composite sandwich, Cellite, load-strain
distributions
Cuvinte cheie: test încovoiere, sandwich compozit, fibră celit, distribuţii
forţă-deformaţie

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29-77 INFLUENŢA DEFECTULUI ASUPRA MODIFICĂRII TEMPERATURII CRITICE LA FLAMB

DAMAGE INFLUENCE ON THE CRITICAL BUCKLING
TEMPERATURE
This paper presents the influence of a transverse damage in a doubleclamped
beam upon the critical buckling temperature. First, the buckling
temperatures and subsequent loads are analytically investigated on an intact
prismatic beam, together with the dynamic behavior in terms of the natural
frequencies. Afterwards, the effect of a transverse damage is considered, and a
relation expressing the frequency alteration due to the crack is provided. To
prove the relation’s validity a finite element analysis was performed for some
particular cases, and the results compared with those obtained analytically. The
investigation did show a good concordance between the results obtained in the
two ways, proving the correctness of the analytical approach.
Keywords: double-clamped beam, damage, thermal buckling
Cuvinte cheie: grindă dublu încastrată, defect, flambaj, temperatură
critică

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29-76 INFLUENTA INTERFEȚEI ȘARJĂ/MATRICE ASUPRA PROPRIETĂȚILOR MECANICE ALE MATERIALELOR COMPOZITE

INFLUENCE OF INTERFACE BATCH/MATRIX COMPOSITE
MATERIALS ON MECHANICAL PROPERTIES
The objective of this article is to present the means used for
experimental characterization of materials studied, the manufacturing process of
composite materials, specimen’s preparation test for metal surfaces required for
imaging by electron microscopy, and behavior analyzing interface/matrix.
Keywords: composite materials, resins, kaolin
Cuvinte cheie: materiale compozite, rășini, caolin

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29-74 ENEGIA DE DEFORMARE DIN DISCUL BIPLAN AL VANEI FLUTURE

STRAIN ENERGY IN A BUTTERFLY VALVE BIPLAN DISK
The papers present the strain energy that appears in a biplane disc of
the butterfly valve by using the numerical methods. Due to the eccentricities of
the biplane butterfly disc the obtained stresses and displacements are not
uniform in the whole structure of the disc. The study of the strain energy allows
us a qualitative evaluation of the energy distribution in the biplane disc when
external loads act on the upstream side of the disc.
Keywords: deformation energy, biplane butterfly valve disc, stresses,
strains
Cuvinte cheie: energie de deformare, disc biplan vană fluture, tensiuni,
deformaţii

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29-73 SUPRAFEŢE NEUTRE PENTRU DISCULUI BIPLAN AL VANEI FLUTURE

NEUTRAL SURFACES FOR BUTTERFLY VALVE BIPLAN DISK
Due to the eccentricities of the biplane disc of the butterfly valve, the
analysis of the directional stresses can be done by using the numerical
methods. The paper presents the neutral surfaces of butterfly valve biplane disc
obtained by numerical methods. The neutral surfaces are defined as surfaces
with directional stress of zero value or, those surfaces which delimit the passing
of the directional stresses from negative values to positive values.
Keywords: neutral surfaces, butterfly valve disc, tensions
Cuvinte cheie: suprafeţe neutre, disc vană fluture, tensiuni

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29-72 RECONSTITUIREA GEOMETRIEI COMPONENTELOR MECANICE PRIN FOTOGRAMETRIE PARTEA A II-A

3D RECONSTRUCTION OF THE MECHANICAL PARTS
GEOMETRY THROUGH PHOTOGRAMMETRY – PART II
The paper has the following objectives: to describe the
Photogrammetry technique, to present its principles and results, to review
photogrammetry software and to exemplify some applications in the field of
mechanical parts that were made with said software.
Keywords: photogrammetry, part, mechanical
Cuvinte cheie: fotogrametrie, componente, mecanice

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29-71 RECONSTITUIREA GEOMETRIEI COMPONENTELOR MECANICE PRIN FOTOGRAMETRIE PARTEA I

3D RECONSTRUCTION OF THE MECHANICAL PARTS
GEOMETRY THROUGH PHOTOGRAMMETRY – PART I
The paper has the following objectives: to describe the
Photogrammetry technique, to present its principles and results, to review
photogrammetry software and to exemplify some applications in the field of
mechanical parts that were made with said software.
Keywords: photogrammetry, part, mechanical
Cuvinte cheie: fotogrametrie, componente, mecanice

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29-70 METODA SPH ÎN PROBLEME HIDROTEHNICE

SPH METHOD IN HYDRAULIC PROBLEMS
Smoothed Particle Hydrodynamics (SPH) method is a meshless
numerical method, which has many advantages comparatively with Finite
Element Method (FEM), regarding those problems where large displacement,
strong nonlinearities or deformations with high strain rates occur (high velocity
impact problems, air or underwater explosion calculus etc.). As fluid mechanics
is concerned, this method is practically completely validated. Some very difficult
problems, like fluid-structure interaction (FSI), free surface evolution of a fluid
and others, can be easier solved by SPH method. In our country this numerical
method is practically unused and even unknown. This paper comes firstly with
theoretical fundamentals of the SPH method, after that an hypothetical
hydraulic problem is solved. It is about the numerical modeling of a gate which
controls the fluid level between two enclosed spaces. In addition to urging the
use of SPH method, this paper presents an available numerical model, based
on this method, for many others similar problems and useful conclusions.
Keywords: free particles, SPH, Navier -Stokes, flowing, fluid
Cuvinte cheie: particule libere, SPH, ecuaţiile Navier-Stokes, curgere,
fluid

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29-69 UNELE ASPECTE PRIVIND CURGEREA GAZELOR PRIN ŢEVILE LUNGI

SOME ASPECTS OF THE FLOW OF GAS BY LONG PIPES
This paper deals with studying the evolution of gas dynamics
parameters in long pipes. This study is applicable to the design and
construction of special pipes.
Keywords: gas dynamics parameters, enthalpy, perfect gas, Mach
criterion, long pipe, Reynolds criterion
Cuvinte cheie: parametric gazodinamici, entalpie, gaz perfect, criteriul
Mach, ţeavă lungă, criteriul Reynolds

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29-68 CONSIDERAŢII PRIVIND FACTORII CARE DETERMINĂ REZISTENŢA LA ÎNAINARE A CORPURILOR AERODINAMICE ÎN FLUID INCOMPRESIBIL

CONSIDERATIONS FACTORS DETERMINING RESISTANCE
IN SPEED ÎNAINARE BODIES INCOMPRESSIBLE FLUID
This paper addresses issues concerning the influence on friction and
detachment aerodynamic drag bodies in incompressible fluid. The results of
investigations contribute to a more rigorous calculation of flight trajectories of
projectiles and missiles.
Keywords: rocket, projectile, flight path, speed gradient, fluctuations,
similar speeds, aerodynamic force
Cuvinte cheie: rachetă, proiectil, traiectorie de zbor, gradient de viteză,
fluctuaţii, profil de viteze, forţă aerodinamică

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29-67 O ÎNCERCARE DE OBTURARE CU DOP DE GHEAŢĂ A UNUI TRONSON DE CONDUCTĂ ORIZONTALĂ (DN 300 mm) STRĂBĂTUT DE APĂ DEMINERALIZATĂ

A CONTROLLED ICE PLUG FORMING EXPERIMENT
CONDUCTED ON A HORIZONTAL PIPE SECTION (NPS 12)
WITH DEMINERALIZED WATER FLOWING THROUGH
In a hydraulic pipe-line installation, isolating a horizontal section
requires forming one or two ice plugs in a controlled process. This technique is
used for carrying out circuit maintenance or component replacements without
shutting down the entire installation. In both cases, the ice plug (or both ice
plugs) must be maintained until completing the repair activities. This paper
describes an experiment conducted on a horizontal NPS 12 horizontal pipe
section and its sequences, followed by the results and conclusions. The paper
is dedicated to specialists working in research and technological engineering.
Key words: cutting-off the flow, ice deposit, demineralised water,
hydraulic resistance
Cuvinte cheie: oprirea curgerii, depunere de gheaţă, apă
demineralizata, rezistenţa hidraulică

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29-66 MODELAREA SISTEMULUI DE RĂCIRE A ETANŞĂRILOR POMPELOR PRINCIPALE DIN CIRCUITUL PRIMAR DE TRANSPORT AL CĂLDURII LA CNE CERNAVODĂ

CNE CERNAVODA NUCLEAR POWER PLANT PRIMARY
HEAT TRANSPORT PUMPS GLAND SEAL
COOLING SYSTEM MODEL
Primary Heat Transport Pumps Gland Seal Cooling System scope is to
provide a high pressure D2O cooling flow to the primary heat transport pumps
seals. The system safety function is to maintain Primary Heat Transport System
pressure boundary integrity and to prevent radioactivity releases. In order to
monitor the seal operation and to warn of a possible malfunction or failure, the
papers propose an operation model, based on an electric-hydraulics similarity.
Keywords: pumps, gland seal, mathematical model, electric-hydraulics
similarity
Cuvinte cheie: pompe, presgarnitură, model matematic, similitudine
electric hidraulică

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29-65 EFECTELE DISPOZITIVELOR ELECTRONICE ASUPRA STRUCTURII ENERGETICE A FIINȚEI UMANE ȘI RELAȚIA DINTRE STRESUL CRESCUT ȘI PERFORMANȚA DIMINUATĂ

EFFECTS OF ELECTRONIC DEVICES UPON THE HUMAN
BEINGS ENERGETIC STRUCTURE AND THE POSSIBLE
RELATION BETWEEN INCREASED STRESS AND
DIMINISHED PERFORMANCE
This paper examines the effects which the use of electronic devices
may have upon the energetic body of the human being, measured with the
electro-photonic imaging device. The study offers a new perspective upon the
possible effects which may be caused by the use of electronic devices on the
human being. The study is a case study, and may, if considered appropriate,
lay the foundation for a long-term study including more subjects.
Keywords: electro-photonic imaging device, stress, energy, energetic
body
Cuvinte cheie: dispozitiv electro-fotonic, stres, energie, înveliș
energetic

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29-64 COMANDA UNUI SEMAFOR CU TREI CULORI ȘI STARE DE AVARIE FOLOSIND AUTOMATUL PROGRAMABIL ZELIO SCHNEIDER ELECTRIC

CONTROL OF TRAFFIC LIGHT WITH THREE COLOURS AND
HAZARD’S STATE USING PLC ZELIO SCHNEIDER ELECTRIC
This paper presents an application made to control of traffic lights with
three colors and hazard’s state simulated and implemented using ZelioSoft 2.
Also, program has been tested on laboratory bench comprising: a power source
model THF45US24, a PLC Telemecanique Zelio SR3 B261BD type with 24VDC
power supply, and Schenck simulation module with 2 analog inputs, 8 digital
inputs, and 8 relay outputs.
Keywords: wired logic, programmable logic PLC, language FBD
Cuvinte cheie: logică cablată, logică programată, PLC, limbaj FBD

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29-63 CONTROLUL UNUI INVERTOR MONOFAZAT CU MICROCONTROLER PIC

CONTROL OF A SINGLE-PHASE INVERTER WITH
PIC MICROCONTROLLER
This paper presents a single-phase power inverter with transformer with
intermediate connection (in primary circuit) which has the voltage form at the
output rectangular or quasi-sinusoidal shapes. Inverter control (six variants)
was performed with 8-bit PIC microcontroller and power transistors are
MOSFET type. In paper were performed theoretically and experimentally times
switching for transistors to reduce voltage harmonics 3,5,7,9 and 11.
Measurements of electrical parameters were performed for the six control types
when the inverter supplied an incandescent lamp.
Keywords: single-phase inverter, microcontroller, voltage harmonics
Cuvinte cheie: invertor monofazat, microcontroler, armonice de tensiune

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29-62 EFICIENȚA DE COLECTARE A ELECTROFILTRELOR INDUSTRIALE ÎN FUNCȚIE DE STRATURILE DE PRAF DE PE SUPRAFEȚELE COLECTOARE partea a II-a

COLLECTION EFFICIENCY OF INDUSTRIAL
PRECIPITATORS DEPENDING ON POWDER LAYERS
ON COLLECTING SURFACES – Part II
When treating large gas flows, industrial precipitators are the most
common in the industry. For a precipitator with three sections (from a thermal
power plant), the article presents, through simulation (based on real electrical
and technological parameters of a precipitator) collection efficiency,
penetration of dust particles and migration’s velocity depending on thickness of
powder layers on collecting surface.
Keywords: electrostatic precipitators, dust, speed migration, collection
efficiency
Cuvinte cheie: electrofiltre, particule de praf, viteza de migrație, eficiența
de colectare

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29-61 EFICIENȚA DE COLECTARE A ELECTROFILTRELOR INDUSTRIALE ÎN FUNCȚIE DE STRATURILE DE PRAF DE PE SUPRAFEȚELE COLECTOARE partea I-a

COLLECTION EFFICIENCY OF INDUSTRIAL
PRECIPITATORS DEPENDING ON POWDER LAYERS
ON COLLECTING SURFACES – Part I
When treating large gas flows, industrial precipitators are the most
common in the industry. For a precipitator with three sections (from a thermal
power plant), the article presents, through simulation (based on real electrical
and technological parameters of a precipitator) collection efficiency, penetration
of dust particles and migration’s velocity depending on thickness of powder
layers on collecting surface.
Keywords: electrostatic precipitators, dust, speed migration, collection
efficiency
Cuvinte cheie: electrofiltre, particule de praf, viteza de migrație, eficiența
de colectare

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29-60 CIRCUITE LOGICE DE BAZĂ CU STRUCTURĂ VARIABILĂ REALIZATE CU PORŢI ŞI-NU, SAU-NU ŞI SAU-EXCLUSIV, EXPERIMENTATE PE AP PS3

BASIC LOGIC CIRCUITS WITH VARIABLE STRUCTURE
MADE WITH NAND, NOR AND XOR GATES ON PS3 PLC
The paper presents the basic logic circuits made with integrated variable
structure NAND, NOR and XOR. The logical structure and function of these
circuits is changed by means of changeover switches which changes the logic
value of a signal at the input of XOR gates. In this way change the logic circuit
function with variable structure. Were performed experiments on the PS 3 PLC
(Klöckner-Moeller).
Keywords: logic circuits, AND – NOT gate, NOR gate, OR gate weeks
are exclusively allocated
Cuvinte cheie: circuite logice, poartă ȘI-NU, poartă SAU-NU, poartă
SAU -EXCLUSIV

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29-59 DETERMINAREA OPTIMALĂ A PARAMETRILOR GENERATORULUI ELECTRIC ASINCRON CU DOUĂ ÎNFĂŞURĂRI STATORICE – MODELUL MATEMATIC

PARAMETER OPTIMAL IDENTIFICATION OF DUAL THREE
PHASES STATOR WINDING INDUCTION MACHINE –
MATHEMATICAL MODEL
The parameter identification of a dual three phase’s stator winding
induction machine is approached in this paper by the genetic optimal algorithm.
The estimated parameter are: the voltage ratio between main and auxiliary
winding, the main winding resistance and leakage reactance, the cage rotor
resistance and reactance, the coupling leakage reactance between main and
auxiliary winding, the magnetization non saturated reactance, equivalent iron
loss resistance and mechanical losses including their variation with speed.
Keywords: asynchronous generator, two stator windings, equivalent
scheme parameters, calculating the optimal genetic algorithm
Cuvinte cheie: generator electric asincron, două înfăşurări statorice,
parametrii schemei echivalente, calcul optimal cu metoda algoritmilor genetici

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29-58 METODĂ DE DETERMINARE RAPIDĂ A PUTERII UTILE LA O MAŞINĂ ASINCRONĂ

A RAPID METHOD FOR DETERMINING THE NET
POWER OF AN ASYNCHRONOUS MACHINE
This work presents a method to rapidly determine the net power of an
asynchronous machine running as a motor. For this we read a minimal set of
engine speed values, excitation winding current values, power factor values
when we know the nominal values of the tested engine. The find the net power
values we use the phases in drawing up the circle diagram for an electrical
machine. This method can easily used to find the electric energy balance of
various industrial units.
Keywords: net power, asynchronous motor, energy balance, circle
diagram
Cuvinte cheie: puterea utilă, motor asincron, bilanţ electroenergetic,
diagrama cercului

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29-57 ANALOG TO DIGITAL CONVERTER IN DIGITAL PROTECTIVE RELAYS

CONVERTOR ANALOG-DIGITAL
ÎN RELEE DIGITALE DE PROTECȚIE
The accuracy and the speed of decision making of the protection
relays are very important to maintain the continuity of supply to the electrical
power system during different disturbances.
A/D Converter shares an important role in achieving that requirement,
so that all types of A/D Converters used in power relaying applications will be
discussed in this paper and some recommendations will be offered depending
on that discussion.
Acuratețea și viteza de luare a deciziilor a releelor de protecție sunt
foarte importante pentru a menține continuitatea aprovizionării sistemului de
energie electrică în timpul diferitelor perturbații.
A/D convertorul analog-digital are un rol important în realizarea acestei
cerințe, astfel încât toate tipurile de convertoare A/D utilizate în transmiterea
aplicațiilor de putere vor fi discutate în această lucrare și unele recomandări vor
fi oferite în funcție de această discuție.
Keywords: digital relay, digital signal processing, electrical power
system, digitization, quantization, sampling
Cuvinte cheie: releu digital, procesare a semnalului digital, sisteme de
energie electrică, digitizare, cuantizare, eșantionare

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29-56 APROXIMAREA ECUAȚIEI DE REZOLVARE A SITUAȚIEI CABLURILOR ELECTRICE AERIENE UTILIZÂND METODA ITERATIVĂ ȘI PROGRAMAREA C++

SOLVE THE APPROXIMATE SOLUTION FOR THE
STATATMENT EQUATION OF OVER HEAD LINES BY
USING ITTERATIVE METHOD AND C++
The calculation of different parameters for mechanical design of
overhead lines is introduced in this paper. The solution of the equation statement
is done by using iteration methods and c++. Finally, the purpose of this paper is
to realize the optimum design of overhead lines and consequently the better
performance during different weather conditions and load cases.
Key words: overhead lines, mechanical design, sag, equation statement
Cuvinte cheie: linii electrice aeriene, proiectare mecanică, săgeți,
ecuație de stare

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29-55 CONSIDERAȚII ASUPRA CIRCUITULUI CHUA Partea a III-a

CONSIDERATIONS ABOUT CHUA’S CIRCUIT – Part III
This paper presents modeling techniques and design nonlinear memristor
elements type, typically used in Chua’s circuit structure. Extremely laborious
analyzes and mathematical techniques modeling approach is support for
initiating many procedures for designing a linear negative resistance element,
but not only.
Keywords: memristor, nonlinear, converter, circuit
Cuvinte cheie: memristor, neliniar, convertor, circuit

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29-54 CONSIDERAȚII ASUPRA CIRCUITULUI CHUA Partea a II-a

CONSIDERATIONS ABOUT CHUA’S CIRCUIT – Part II
This paper presents modeling techniques and design nonlinear memristor
elements type, typically used in Chua’s circuit structure. Extremely laborious
analyzes and mathematical techniques modeling approach is support for
initiating many procedures for designing a linear negative resistance element,
but not only.
Keywords: memristor, nonlinear, converter, circuit
Cuvinte cheie: memristor, neliniar, convertor, circuit

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29-53 CONSIDERAȚII ASUPRA CIRCUITULUI CHUA Partea I

CONSIDERATIONS ABOUT CHUA’S CIRCUIT – Part I
This paper presents modeling techniques and design nonlinear memristor
elements type, typically used in Chua’s circuit structure. Extremely laborious
analyzes and mathematical techniques modeling approach is support for
initiating many procedures for designing a linear negative resistance element,
but not only.
Keywords: memristor, nonlinear, converter, circuit
Cuvinte cheie: memristor, neliniar, convertor, circuit

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29-52 ASPECTE PRIVIND PIERDERILE PE LINIA DE ALIMENTARE A UNUI CONSUMATOR TRIFAZAT DEZECHILIBRAT

ASPECTS REGARDING THE SUPPLY LINE LOSS OF A
UNBALANCED THREE-PHASED LOAD
The electrical power system normally operated in a symmetrical threephase
steady state mode. However, there are certain situations that can cause
non-symmetrical operations. The presence of the unbalanced three-phased
loads determines the apparition of the non-symmetrical systems involving
currents and voltages as well the extra-loss within the supply wire. In this paper
we present a mathematical proof in Mathcad of additional losses in the electrical
energy transmission line working under non-symmetrical conditions. Was
considered a simplified model, but the obtained result generalizes to complex
electrical circuits. Finally, we draw the conclusions and we indicate the
references.
Keywords: receiver phase, active power, symmetric components,
power transmission line, power line losses, unbalanced mode of operation
mathematical proof of additional losses under unbalanced
Cuvinte cheie: receptor trifazat, putere activă, componente simetrice,
linie de transport a energiei electrice, pierderi pe linia de alimentare, regim
dezechilibrat de funcţionare, demonstraţie matematică a pierderilor
suplimentare în regim dezechilibrat

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29-51 INFLUENŢA FACTORILOR EXTERNI ASUPRA PEREŢILOR BATARDOURILOR METALICE DESTINATE PROTEJĂRII RÂURILOR ÎN CAZ DE DEZASTRE NATURALE

THE INFLUENCE OF THE EXTERN FACTORS ONTHE WALLS
OF THE METALLIC BULKHEADS FOR PROTECTING THE
RIVER IN CASE OF NATURAL DISASTERS
The paper aims to influence of a specific factors in case of flood (flow,
the flow rate of water) concerning the walls of the metallic bulkheads used for
protecting the banks of the rivers
Keywords: bulkhead, flood, flow, flow rate, distortion walls
Cuvinte cheie:batardou, inundaţii, debit, viteză, deformaţii pereţi

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29-50 DESFĂŞURAREA VIROLELOR UNEI CAMERE SPIRALE UTILIZÂND MODULUL SHEET METAL DIN SOLIDWORKS

THE FLATTENING OF THE SPIRAL CASING SHELLS USING
THE SOLIDWORKS SHEET METAL MODULE
The objective of the paper is to describe the flattening of the spiral
casing shells using the Sheet Metal module included in SolidWorks software.
Sheet Metal parts constitute a very specific type of solid model. They have the
characteristics of being thin walled and the wall thickness is constant
throughout the model.
Keywords: Flatten, SolidWorks, hydraulic turbines, spiral casing
Cuvinte cheie: Desfăşurate, SolidWorks, turbine hidraulice, camera
spirală

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29-49 MATERIALE SPECIFICE FABRICAȚIEI MAȘINILOR HIDRAULICE ȘI COMPORTAREA LOR LA FENOMENUL DE EROZIUNE

SPECIFIC MATERIALS USED IN MANUFACTURING
HYDRAULIC TURBINES AND THEIR BEHAVIOR TO EROSION
The goal of the paper is regarding the alloy materials used in the
manufacturing of hydraulic machines and how the process of corrosion has
influenced these materials. The mechanism of silt erosion is discussed and are
compared the effects of erosion and cavitational phenomena.
Keyword: corrosio, erosion abrasiv, hydraulic machine, stainless steel
Cuvinte cheie: coroziune, eroziune abrazivă, masini hidraulice, oțeluri
inoxidabile

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29-48 PROBLEME DE MENTENANŢĂ SPECIFICE SISTEMELOR DE ACŢIONARE HIDRAULICĂ

SPECIFIC ISSUES FOR MAINTENANCE OF
HYDRAULIC DRIVE SYSTEMS
This paper presents the concepts of maintenance in the light of ISO’s
standards and EU directives implemented in Romania after the year 2007, in
the industrial field, with reference to the hydraulic drive systems. The
maintenance of these systems can only find a practical solution in accordance
with the international standards and European directives mentioned above.
Keywords: tree maintenance, total productive maintenance, hydraulic
actuators, standards
Cuvinte cheie: arbore mentenanță, mentenanţă productivă totală,
acţionări hidraulice, standarde

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29-47 ANALIZA REGIMURILOR TERMICE ALE UNUI HIDROGENERATOR

ANALYSIS OF A HYDRO GENERATOR THERMAL REGIMES
The paper analyses the thermal regimes of a vertical synchronous hydro
generator, coupled with a Kaplan hydraulic turbine, depending on its active and
reactive powers. Operation at temperatures higher than permissible limits leads
to defects and abnormal functioning of hydro generator. The optimal
temperature increases stability and extends the lifetime of hydro generator, by
slowing aging of the rotor and stator windings.
Keywords: hydro, monitoring, temperature
Cuvinte cheie: hidrogenerator, monitorizare, regim termic

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29-46 OPTIMIZAREA FUNCȚIONĂRII UNEI PRIZE DE APĂ ECOLOGICE PRIN TESTAREA UNUI MODEL LA SCARĂ REDUSĂ

ECOLOGICAL WATER INTAKE OPTIMIZATION BY SMALL
SCALE MODELLING
The main objective of the paper is to demonstrate the efficiency of an
ecological water intake by optimizing its operation using experimental modelling
techniques. The tests have been performed on a dedicated small scale model
integrated in a specially design testing flume.
This paper presents the general considerations regarding the ecological
intakes for Mountain Rivers and focuses on identifying design methods suitable
for performance increasing. A simplified prototype installation was designed
starting from the patented sand-less ecological intake. Based on this design, a
1:10 small scale model was developed and installed in a dedicated stand. It
was possible to determine the water speed, the flow from the main channel and
the captured flow in different testing conditions, by using specific measuring
equipment and methods. The obtained results were transposed to the prototype
installation by applying Froude similarity criteria, proving to be useful to the
elaboration of the main design parameters for water intakes.
Keywords: water intakes, Mountain Rivers, experimental model, similarity
Cuvinte cheie: prize de apă, râuri de munte, model experimental,
similitudine

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