Vilnius Gediminas Technical University
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Analysis and assessment of biological treatment processes in a small-scale wastewater treatment plant
No full textWith stricter requirements for wastewater treatment, small-scale individual wastewater treatment
plants can provide a financially attractive alternative to a sever connection in locations far from the existing
sewer network. Systems operating under the basis of active sludge are considered advanced, and their
producers declare high levels of wastewater treatment not only according to BOD, but also under biogenic
materials. However, there are hardly any data on how small-scale individual household wastewater
treatment facilities operate. This article presents an analysis of the main parameters of wastewater
biologically treated in three small-scale household wastewater treatment plants (which operate under the
basis of active sludge), namely TSS, COD, BOD7, Nt, NO3-N, NH4-N, Pt, and PO4-P concentrations. The
research lasted for 5.5 months during a cold period. According to TSS, COD, and BOD7 concentrations
in effluent, the wastewater treatment level in the study plants was good. The concentrations of these
substances in effluent (TSS<10 mg/L, COD<98 mg/L, BOD7<20 mg/L) were lower than requirements
for treated water. However, NH4-N in the effluent in winter increased up to 6-7 mg/L and to 26 mg/L.
The concentrations of Nt and Pt in treated wastewater exceeded EU requirements for water released from
wastewater treatment facilities. PO4-P removal, in many cases, was ineffective or did not take place at all
Sustainability assessment of the new residential projects in the Baltic States: a multiple criteria approach
No full textHousing is one of the most important public priorities affecting urban development and
therefore has a significant impact on sustainable development. A housing project can be regarded as
sustainable only when all the dimensions of sustainability (environmental, economic, and social) are
dealt with. The aim of the present article is to propose an integrated, hierarchy-based, multiple-criteria
approach for the sustainability assessment of new residential development projects, which is achieved
through the accomplishment of three objectives. First, this paper proposes an original framework
for a multiple-criteria assessment of new residential projects. Second, the proposed methodology is
demonstrated in the assessment of nine residential development projects in Lithuania, Latvia, and
Estonia according to a hierarchical system of 53 sustainability indicators developed specifically for
the Baltic context. Finally, based on the research results, the paper proposes recommendations to
stakeholders for enhancing the performance of new residential projects according to the principles
of sustainability. The proposed sustainability assessment approach is not limited to the Baltic States
and can also be used in other countries, applying the adapted sustainability assessment indicators
Promoting sustainability through investment in Building Information Modeling (BIM) technologies: a design company perspective
No full textThe aim of this article is to enhance the understanding of how design companies perceive
the benefits of Building Information Modeling (BIM) technologies application. BIM is recognized in
the literature as a (potentially) powerful driver leading the construction sector towards sustainability.
However, for design companies, the choice to invest in BIM technologies is basically an economic
one. Specifically, a design company assesses economic benefits and efficiency improvements thanks
to the application of BIM technologies. The article discusses the return on investments (ROI) in BIM
technologies and reviews ROI calculation methodologies proposed by other authors. In order to
evaluate BIM return on investment correctly practical ROI calculations are carried out. Appropriate
methods, together with the relevant variables for ROI calculation, are developed. The study allows
for adjusting the calculation method making it more accurate and understandable using the Autodesk
Revit based ROI calculation of the first year
An algorithm for modelling the impact of the judicial conflict-resolution process on construction investment
Get PDFIn this article, the modelling of the judicial conflict-resolution process is considered
from a construction investor’s point of view. Such modelling is important for improving the risk
management for construction investors and supporting sustainable city development by supporting
the development of rules regulating the construction process. Thus, this raises the problem of
evaluation of different decisions and selection of the optimal one followed by distribution extraction.
First, the example of such a process is analysed and schematically represented. Then, it is formalised
as a graph, which is described in the form of a decision graph with cycles. We use some natural
problem properties and provide the algorithm to convert this graph into a tree. Then, we propose
the algorithm to evaluate profits for different scenarios with estimation of time, which is done by
integration of an average daily costs function. Afterwards, the optimisation problem is solved
and the optimal investor strategy is obtained—this allows one to extract the construction project
profit distribution, which can be used for further analysis by standard risk (and other important
information)-evaluation techniques. The overall algorithm complexity is analysed, the computational
experiment is performed and conclusions are formulated
The usage of a laser height sensors for estimating road unevenness profile
No full textThe paper presents results of simulation and experimental tests of proposed algorithm of
compensation vehicle vertical and pitch dynamics in laser signals to get an estimation of road
unevenness profile. In the beginning of the paper the problem of defining actual road unevenness
profile height was described and a method to solve this problem was proposed. The described
problem arises from the fact that measurement of the distance between laser height sensor and
road is done with a sensor mounted to the vehicle body, which have its own dynamics. The method
of compensation laser sensor signal for body movement – pitch and heave – was proposed and
tested with simulation and experimental tests. For simulation tests half car model implemented in
a Simulink and Matlab was used and for experimental test passenger car Opel Astra was used with
algorithm implemented in dSpace electronic control unit prototyping system. Simulation test proved
that the idea is correct and allows to fully compensate laser signal for body movement. Experimental
test showed that method is easy to implement and fully effective in a simulation environment but is much more complicated with a real application. It is because information about body movement
is not accurate as in a simulation and a special signal processing methods need to be added to
procedure working with a simulation signals. Acceleration signals must be integrated with use of
a special band pass filtering, but with its use it is able to get good results of compensation also with
a real car and real sensor signals
Evaluation of alternatives to integrate special transportation services for people with movement disorders
No full textIntegrating the most appropriate special transportation service for people with movement disorders model may result in
great economy efficiency and social benefit balance. However, most existing researches are based on improving the accessibility of
public transport services or development of routing and scheduling under stochastic input data. The aim of this paper is to project
the evaluation algorithm for the purpose of assessing the appropriate model of integration which would enable the employment of
existing resources and filling the gap in assurance the mobility needs of people with mobility impairments. This paper identifies the
evaluation indicators which are selected from international publications. Firstly the performance indicators of special transportation
services were selected, further the sustainable development of public transport services evaluation indicators were selected,
classified and adjusted to the goal of this paper. As a final result of indicators selection, a set of indicators classified into two groups
– cost and benefit - was carried out. The decision making is based on Fuzzy Analytic Hierarchy Process and Fuzzy Technique for
Order Preference by Similarity to Ideal Solution methods. A case study is provided to demonstrate the application of proposed
evaluation algorithm
Analysis of identification of digital images from a map of cosmic microwaves
No full textThis paper discusses identification of digital images from the cosmic microwave background radiation map formed according to the data of the European Space Agency “Planck” telescope by applying covariance functions and wavelet theory. The estimates of covariance functions of two digital images or single images are calculated according to the random functions formed of the digital images in the form of pixel vectors. The estimates of pixel vectors are formed on expansion of the pixel arrays of the digital images by a single vector. When the scale of a digital image is varied, the frequencies of single-pixel color waves remain constant and the procedure for calculation of covariance functions is not affected. For identification of the images, the RGB format spectrum has been applied. The impact of RGB spectrum components and the color tensor on the estimates of covariance functions was analyzed. The identity of digital images is assessed according to the changes in the values of the correlation coefficients in a certain range of values by applying the developed computer program
Renewable Energy Technology Selection Problem Using Integrated H-SWARA-MULTIMOORA Approach
No full textDue to the adaptation of recent pollution mitigation and justification policies there has been a growing trend for electricity generation from various renewable resources. The selection of the optimal renewable energy technology could be measured as a complex problem due to the complication of forthcoming circumstances in any country. Consequently, the proposed similar complex assessment problem can be tackled with the support of Multiple Attribute Decision Making (MADM) methods. The current research study investigates a technology selection problem by proposing a hybrid MADM approach based on the Step-Wise Weight Assessment Ratio Analysis (SWARA) approach with a hierarchical arrangement combined with the Multi-Objective Optimization on the basis of Ratio Analysis plus the full MULTIplicative form (MULTIMOORA). Ultimately, a conceptual case study regarding the selection of the optimal renewable energy technology based on a conceptual development project in Iran has been examined by the proposed combinative MADM methodology.This article belongs to the Special Issue Multi-Objective and Multi-Attribute Optimisation for Sustainable Development Decision Aidin
Impact of Dynamic Non-Equilibrium Processes on Fracture Mechanisms of High-Strength Titanium Alloy VT23
No full textThe complex analysis of fractures of high-strength titanium alloy VT23 was performed at the macro- and microlevels, and the basic patterns of fracture under static stretching and after the realization of dynamic non-equilibrium processes caused by impact-oscillatory loading and subsequent static stretching were revealed. The morphological regularities in the formation of dimples of tearing and alloy stratification at the macro level were established with the help of 3-D profilometry. The micromechanisms of fracture were numerically characterized by the methods of optical-digital analysis, in particular, by highlighting the bound areas, which are the objects of interest—the dimples of tearing. The analysis of the surface of ductile tearing under different loading conditions at the microlevel was performed by analyzing the parameter distribution patterns of the dimples found on it
Customization Model for Assessing the Commercial Potential of Technologies to Different Technology Manufacturing Branches: Development a Set of Factors
Get PDFPreviously developed model for assessing the commercial potential of technologies is universal—dedicated for assessment technologies in all manufacturing branches. However, in the course of research has been established, that specifics of different technology manufacturing branches (DTMB) are important for assessing the commercial potential. Historically, several technology manufacturing branches had already positive results in Lithuania, they cover the most promising part of the national economy and are in line with EU priorities. For these reasons a decision was taken to customize the model for assessing the commercial potential of technologies to biotechnology, mechatronics, laser technology, information technology, nano electronics. The article presents development a sets of factors for assessment commercial potential for different technology manufacturing branches based on multiple criteria decision making (MCDM) methods. Afterwards sets of factors will be used as the research tool for determination meanings of factors values and the significance of factors for every manufacturing branche.This article belongs to the Proceedings of The 2nd Entrepreneurship and Family Enterprise Research International ConferenceThis research is/was funded by the European Social Fund under the No. 09.3.3-LMT-K-712
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