Vilnius Gediminas Technical University
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Dual mode 4th order active-RC low-pass filter with tunable cut-off frequency from 3 MHz to 20 MHz in 65 nm CMOS
No full textIn this paper, a 4 th order active-RC filter with two approximation modes and a tunable bandwidth from 3 MHz to 20 MHz is presented. The filter can be configured to achieve maximally flat in-band magnitude or phase response by using a dual mode resistor bank and h as gain control. PVT induced parameter drift compensation is accomplished by using a reduced-in-size resistor bank structure made of series and parallel connected resistors. Furthermore, a, design method for the resistor bank is presented, that allows component value calculation based on a ccuracy and tuning step requirements. The power dissipation is bandwidth depended and ranges from 13 mW to 23 mW from a 1.2 V supply for the entire tuning range, while the SFDR is higher than 72 dB and 65 dB at min and max bandwidth settings respectively. The proposed filter is designed and its parameters verified by using 65 nm CMOS technology and occupy a layout area of 0.172mm 2
Modelling of International Transfer of Good Practices of Innovation Management Under Conditions of European Integration
Get PDFThis dissertation analyses the innovation needs of candidate and possible candidate countries of European Union, as well as the good practices and progressive experience of Central-East European countries in order to trans-fer their experiences in innovation management based on its development and needs, opportunities and prospects of capacity and capability improvement. The aim of the thesis is to create an international transfer model of good practices in innovation management which is relevant to the con-temporary needs of candidate and possible candidate countries of European Union, based on explored practices of innovation management in Central-East European countries in order to develop innovation infrastructure and activities in candidate and possible candidate countries with researched factors that influence the transfer process of good practice and progressive experiences.
An original system of indicators for characterization, a technique for multi-criteria assessment of innovation needs in candidate and possible candidate countries, and good practices and progressive experiences of the Central-East European countries are presented in this dissertation. This dissertation, consists of an introduction, three chapters, general conclusions, references, list of author’s scientific publications and annexes. The introduction presents the research problem, the importance of the thesis and its scientific novelty. It reveals the object of the research and describes the goals of the paper, as well as its research methodology and practical significance.
The review of scientific literature is performed in Chapter 1, together with the opportunities and need for international transfer of good practices in innovation management in candidate and possible candidate countries of the European Union in order to prompt integration and accession process. This is done by analyzing scientific literature in the field of innovation, innovation management and public innovation support regarding enlargement conditions of the European Union.
Chapter 2 presents theoretical model and methods applicable for quantitative assessment of the good practices and progressive experiences of Central-East European countries in innovation management, as well as the needs of innovation in candidate and possible candidate countries that are generalized and considered as international transfer model of good practices in innovation management.
The practical application of the proposed model is presented in Chapter 3. The performed empirical research confirms the practical applicability of the international transfer model of good practices in innovation management and reveals perspectives and limitations for its use.
7 scientific papers focusing on the subject of the discussed dissertation have been published, 10 presentations, 3 of which were at international conferences were given
Analysis in material selection: influence of normalization tools on COPRAS-G
No full textMulti criteria decision making (MCDM) methods algorithms are influenced by many parameters and variables as orientation of attributes, aggregation attitude, weights and normalization tools. Various MCDM methods find solution for decision problems using different normalization methods. Normalization process has an important role in decision process and can modify the ranking and final decision. Due to uncertainty associated with data in decision making about materials and design, COPRAS method with interval numbers (COPRAS-G) was recognized as a promising approach in this regard. This paper intends to apply COPRAS-G method in several specific material evaluation studies. Normalization tools are positioned in COPRAS method to check the effect of each tool. Two examples of material and design selection projects are recognized suitable for this study. The results show depending on the number of criteria and number of alternatives material, ranking can be changed when a different normalization tools are considered. This help designers and engineers to achieve a compromise on design decision making process, especially when the material properties and design performance criteria are affected from stochastic nature of design and manufacturing parameters
Intellectual capital as a driving force of internationalization: a case of Lithuanian SMEs
No full textConstantly changing technologies, increasing competition, unstable demand of consumers, economic and political changes encourage managers to seek new opportunities abroad and thus, expand their firms’ activities. Considering the importance of knowledge in a number of industries, competition is shaped by the firms’ intellectual capital. Referring to the intellectual capital theory, the assumption about the importance of intellectual resources in internationalization process is suggested. Grounded on intellectual capital theory and the main aspects of SMEs internationalization the paper aims to reveal the significance of some important factors in internationalization of Lithuanian SMEs. The study is based on expert evaluation method and reports the findings from questioning the representatives of science and business. The internationalization of SMEs is driven by work experience of employees, ability to transmit experience and international orientation of managers. These factors contribute to the development of technical knowledge and strategy development processes. Consequently, obtained technical expertise and strategies lead to the higher reputation of managers in international context. The findings are significant for entrepreneurs having strong intentions to expand their businesses and policy makers, concerning about promotion and support of internationalization processes. The insights into the development of future investigations are suggested
Low-temperature performance of semiconducting asymmetric nanochannel diodes
Get PDFWe present our studies on fabrication and electrical and optical characterization of
semiconducting asymmetric nanochannel diodes (ANCDs), focusing mainly on the temperature dependence of their current–voltage (I–V) characteristics in the range from room temperature to
77 K. These measurements enable us to elucidate the electron transport mechanism in a nanochannel. Our test devices were fabricated in a GaAs/AlGaAs heterostructure with a twodimensional
electron gas layer and were patterned using electron-beam lithography. The 250-nmwide, 70-nm-deep trenches that define the nanochannel were ion-beam etched using the photoresist as a mask, so the resulting nanostructure consisted of approximately ten ANCDs
connected in parallel with 2-μm-long, 230-nm-wide nanochannels. The ANCD I–V curves
collected in the dark exhibited nonlinear, diode-type behavior at all tested temperatures. Their
forward-biased regions were fitted to the classical diode equation with a thermionic barrier, with the ideality factor n and the saturation current as fitting parameters. We have obtained very good
fits, but with n as large as ~50, suggesting that there must be a substantial voltage drop likely at
the contact pads. The thermionic energy barrier was determined to be 56 meV at high temperatures. We have also observed that under optical illumination our ANCDs at low temperatures exhibited, at low illumination powers, a very strong photoresponse enhancement that exceeded that at room temperature. At 78 K, the responsivity was of the order of 104 A/W at the nW-level light excitation
Assessing the performance of the construction sectors in the Baltic States and Poland
No full textThe paper describes the evaluation of the construction market performance in three Baltic states,
including Estonia, Latvia, Lithuania and Poland, based on using structural statistical criteria. The evaluation
covers various periods of time, embracing the time before the economic crisis, in 2007, during the economic
crisis, in 2009, and after the economic crisis, in 2013. For assessing the efficiency of their construction
sectors’ performance, the investigated countries are arranged in the order of preference according to this
indicator by using three multiple-criteria decision making methods (MCDM), such as SAW, TOPSIS and
COPRAS. These evaluation methods are based on determining the weights of the structural criteria used.
For this purpose, three various methods, including the entropy, the method of the criteria impact loss
(CILOS) and a new method of determining the objective criteria weights (IDOCRIW) suggested by the
authors. The results obtained allowed the researchers to assess the construction market performance in the
considered states in various periods of time, to compare them with other countries and to rank them based
on this parameter. Therefore, the suggested method of market performance evaluation may be used as an
effective supplementary aid for determining the priorities in the future business development, as well as for
studying the competitive markets or directing the cash flows of an enterprise to the appropriate areas
Evaluating the significance of criteria contributing to decision-making on brownfield land redevelopment strategies in urban areas
No full textBrownfield land is one of the least exploited resources for urban development in a number
of Eastern European countries. Establishing a rational strategy for redeveloping brownfields is
an unambiguously complex task that requires considering a number of different economic, social,
physical and environmental factors. The strategic decision-making has a long term impact on the
quality of life, ecological balance and urban structure. Therefore, the paper is aimed at developing a
comprehensive set of criteria that contribute to the redevelopment of brownfield land in urban areas.
It focuses on six main development strategies that embrace creating residential, green, commercial,
recreational activity and industrial areas or leaving land as a reserve. Geographic information system
(GIS) tools are employed to collect the spatial information, obtain the initial set of criteria and derive
the statistical data. Expert’s evaluations along with a statistical method of gauging the level of
concordance of their opinion combined with Delphi method are used for determining significance
of criteria within economic, social, physical (urbanistic) and environmental criteria groups. This
study establishes the most significant criteria for implementing different scenarios of the brownfield
land redevelopment in Vilnius, Lithuania. Developed framework will support the decision-making
process in the brownfield land redevelopment aiding a sustainable urban planning
Evolution of traveller experience quality perception in European level policy documents and the case study for Siauliai
No full textEU’s goal is to develop transport system which meets the economic, social and environmental requirements of society.
Since first White paper on Transport in 1992 there was evolution of perception of quality and attributes of quality. The basic set of
quality requirement is based on frequency, price, safety and security were dominating in 1992-2006, however since 2006 new
attributes such as environment impact, and energy efficiency comes into force in European documents. However research case in
Siauliai town show that it delays in user perception of quality
Possibilities to evaluate employee knowledge as a component of knowledge synergy at organisation
No full textKnowledge evaluation and management is one of the key tasks in any organisation aiming to improve the efficiency of its activities, create an environment in which employees are unconditionally willing and are able to share their knowledge and generate new knowledge, thus creating a higher added value and a modern, synergy processes-based and sustainable organisation. Employee knowledge – a component of organisational knowledge synergy – is multifaceted and consists of different content factors with quantitative and qualitative expressions. A comprehensive evaluation of this object requires multi-criteria evaluation methods to transform data, build a hierarchy of indicators and get an aggregated estimate. The article analyses the employee knowledge evaluation process and characteristics of multi-criteria evaluation methods, explaining why they are used in employee knowledge evaluation
Evaluation of quality assurance in contractor contracts by multi-attribute decision-making methods
Get PDFThe goal of this paper is to compare quality assurance in different contractor contracts by means of multi-attribute decision-making (MADM) and to select the best option. For this investigation, the authors have developed the complex of quality evaluation criteria. During experimental evaluation, the significance of criteria was determined and the expert evaluation of template construction contracts was performed. The complex comparison of contractor contracts was carried out by means of the following MADM methods: Simple Additive Weighting (SAW), Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS), Complex Proportional Assessment (COPRAS) as well as the new Evaluation Based on Distance from Average Solution (EDAS). MADM. method. To determine the weights of criteria, with due consideration of uncertainty of expert evaluation, the Fuzzy Analytic Hierarchy Process (FAHP) method was applied. Evaluation of the data structure was performed by methods for the determination of objective weights: an entropy method and new criteria impact loss (CILOS) and integrated determination of objective criteria weights (IDOCRIW) methods. Expert subjective and objective weights were combined into aggregate weights. Based on the investigation performed, the authors make conclusions regarding possibilities for improving quality assurance in contractor contracts