Vilnius Gediminas Technical University
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A Robust Identification of the Protein Standard Bands in Two-Dimensional Electrophoresis Gel Images
No full textThe aim of the investigation presented in this paper was to develop a software-based assistant for the protein analysis workflow. The prior characterization of the unknown protein in two-dimensional electrophoresis gel images is performed according to the molecular weight and isoelectric point of each protein spot estimated from the gel image before further sequence analysis by mass spectrometry. The paper presents a method for automatic and robust identification of the protein standard band in a two-dimensional gel image. In addition, the method introduces the identification of the positions of the markers, prepared by using pre-selected proteins with known molecular mass. The robustness of the method was achieved by using special validation rules in the proposed original algorithms. In addition, a self-organizing map-based decision support algorithm is proposed, which takes Gabor coefficients as image features and searches for the differences in preselected vertical image bars. The experimental investigation proved the good performance of the new algorithms included into the proposed method. The detection of the protein standard markers works without modification of algorithm parameters on two-dimensional gel images obtained by using different staining and destaining procedures, which results in different average levels of intensity in the images
Interval type-2 fuzzy c-control charts: an application in a food company
No full textMany papers exist on ordinary fuzzy control charts in literature in order to consider the
vagueness and uncertainty in observation data. These are on both variable and attribute control
charts. Several extensions of fuzzy sets have appeared in literature since ordinary fuzzy sets emerged.
Type-2 fuzzy sets are one of these extensions. Type-2 fuzzy sets take into account the imprecision of
membership functions in three dimensions. The aim of this paper is to develop interval type-2 fuzzy
control charts for number of nonconformities, briefly c-control charts. In this paper, the theoretical
structure of interval type-2 fuzzy c-control charts is proposed for the first time and the application
is implemented in a food company
Biodyzelino naudojimo galimybės ir perspektyvos Lietuvoje
No full textLietuvos laukia nauji iššūkiai siekiant, kad iki 2020 metų biodegalai sudarytų ne mažiau kaip 10 % bendros energijos suvartojimo transporto sektoriuje. Siekiant šių rezultatų, labai svarbu palankios teisinė, ekonominė, socialinė, technologinė, bei aplinkosauginė aplinkos, kurios turi būti palankios ir skatinančios, bei užtikrinančios biodegalų gamybą ir platinimą Lietuvos rinkoje. Šiame straipsnyje analizuojami Lietuvos Respublikos įstatymai ir Europos Parlamento ir Tarybos direktyvos dėl biodegalų ir atsinaujinančių degalų naudojimo transporto sektoriuje skatinimo. Taip pat pateikti aplinkos taršos mokesčių skaičiavimo rezultatai, panaudojant gryną mineralinį dyzeliną, bei vertinamos II kartos biodyzelino NExBTL degalų gamybos išlaidos
Mechaninių dinaminių sistemų diagnostika
No full textDirbančiose mechaninėse dinaminėse sistemose pastoviai susiduriama su įvairiais veiksniais,
virpesiais, temperatūros pokyčiais ir t.t. Virpesiai labai svarbūs mašinų gamyboje, technologiniuose procesuose, statyboje
ir kitose srityse. Virpesiai gali būti ne tik žalingi, bet ir naudingi. Kiekvienas mechanizmas turi savo optimalų
temperatūrinį lygį. Matuojant virpesius, temperatūros pokyčius ir kitus mechaninių dinaminių sistemų eksploatacijai
svarbius parametrus galime įvertinti jų būklę. Gautus rezultatus galima panaudoti įvairiems technologiniams procesams
atlikti, naujoms mašinoms kurti ir jas eksploatuoti. Straipsnyje nagrinėjamos mechaninių dinaminių sistemų diagnostikos
galimybės. Aprašyti mechaninių dinaminių sistemų diagnostikai naudojamos priemonės matavimų bei analizės atlikimo
metodika bei rezultatų tyrimų etapai. Diagnostikos rezultatai parodo tiriamos sistemos momentinę būklę bei leidžia
numatyti gedimų atsiradimo priežastis bei pasekmes
Excitation of 2D resonant oscillations in piezoelectric plate with additional masses
Get PDFThis article presents results of investigation of piezoelectric transducer which consists
of rectangle homogeneous piezoceramic plate with two additional masses glued on the top surface
of the transducer. Because of additional masses and a certain sectioning of piezoelectric
electrodes, the vibration forms of the plate and resonant frequencies are changed, therefore, the
plate generates 3D longitudinal and bending vibrations. Numerical and experimental investigation
showed that the masses glued at the surface of piezoelectric plate obtain elliptical trajectories of
motion when the first mode of longitudinal vibrations of the plate is excited. Such form of
vibrations of the masses enables using them for various piezoelectric drive mechanisms as contact
elements and to transform high-frequency vibrations into the directional or rotational movement
of the rotor or slider. In order to examine the deformations and dynamic characteristics of the
homogenous piezoelectric plate with two additional masses, the numerical modelling of such
piezo transducer and the experimental study have been carried out
Vizualinės komunikacijos klišės pramogų industrijoje: tango šokis kinematografijoje
No full textTyrimas skirtas vienai svarbiausių ir didžiausią apyvartą turinčių pramogų industrijos šakų – komerciniam
kinui. Nagrinėjami tango motyvai Vakarų kinematografijos istorijoje, išryškinamos Holivudo istorijos ir
tango šokio bei muzikos sąsajos. Svarstomos priežastys, lėmusios miuziklų, komedijų, dramų bei veiksmo filmų kūrėjų susidomėjimą šiuo aistringu, melancholišku, dažnai dramatišku šokiu, demaskuojamos klišės,
į kurias Holivudo filmo industrija įspraudė šį šokį. Parodoma, kaip, pradedant filmu Keturi Apokalipsės
raiteliai (1921), kinematografijoje susiformavo socialiniam tango šokiui nebūdingas „kietojo” tango stereotipas.
Šis tango stilius, parankus siekiant perteikti aistrą, pyktį ir kitus dramatiškus jausmus, regimas tokiuose
filmuose, kaip Saulėlydžio bulvaras (1950), Džiaze tik merginos (1959), Paskutinysis tango Paryžiuje
(1972), Kareivis iš Oranje (1977), Melas vardan tiesos (1994) ir kituose. Paskutiniajame XX a. dešimtmetyje
sukurtuose filmuose, tokiuose kaip Alisa (1990), Moters kvapas (1992), Indokinija (1992), šis šokis dažniau
siejamas su kova už laisvę, savęs tvirtinimu, tačiau esminės klišės taip ir nebuvo įveiktos
Development and verification of a shock absorber and its shim valve model based on the force method principles
No full textIn this paper, a mathematical model of a monotube shock absorber’s shim valve, which is developed by applying the force (flexibility)
method, is described. This method expresses the relationship between displacements and the forces existing in the shock
absorber structure. An application of the force method in the field of practical modification of vehicle shock absorbers enables to
effectively analyse the influence of a wide range of parameters, including the number of shims in the valve, their disposition and
the properties of the material on the level of the damping force. The damping of the shock absorber considerably impacts comfort
and road holding characteristics of the vehicle. In addition, a whole model of a monotube shock absorber is designed in this paper.
The validation and practical application of the mathematical model were evaluated by carrying out experimental measuring of the
characteristics of the shock absorber using a special stand
Criteria system of emergency situations risks assessment in the Baltic sea ports
No full textThis paper reviews the principles of transportation risk assessment in the Baltic Sea ports and hinterland. The essential
steps of assessment are the identification of primary criterions, the determining the underlying criterion groups and quantitative
assessment of international environment indicators and nature, infrastructure indicators and organizational indicators on the basis of
the multiple-criteria evaluation methods. Designed system of criteria creates a possibility for objective evaluation of risk
management processes and allows planning objectively long-term risk management strategy in the ports according to certain
economic development circumstances
Experimental and analytical investigation of deformations and stress distribution in steel bands of a two-span stress-ribbon pedestrian bridge
No full textThe article is dedicated to the analysis of problems related to design of pedestrian bridges with flexible ribbon bands made of steel. The study is based on test results of a bridge model that has two spans (each with a length of five meters). A simplified analytical technique has been proposed for predicting vertical deformations of the bridge structure subjected to symmetrical or asymmetrical loading patterns. The technique also allows assessing the tension forces in the ribbons, which are very important for design of such structures. The analysis reveals the importance of the flexural rigidity of the ribbons that might cause significant redistribution of stresses within the steel bands
Evaluation of comfort level and harvested energy in the vehicle using controlled damping
No full textShock absorbers allow the damping of suspension vibrations, by dissipating kinetic energy.
This energy theoretically can be harvested; however, practical solutions are not easily obtainable.
This paper is dedicated to analyzing and evaluating the vibration energy in a vehicle’s suspension
that is generated by road excitations. Also, it estimates the possible amount of harvested energy
required to diminish accelerations of the vehicle body, the driver, or the passenger center of mass.
The control of damper is realized by optimizing the best damping coefficient for different road
roughness. Analytical results, obtained from the proposed dynamic model of the car, were compared
with experimental data, showing a good coherence between them. These results allow us to evaluate
the amount of energy circulating within shock absorbers and give information about the amount of
the possible harvested energy. There is a very good relationship between energy needed for control
and gained energ