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Modelling Water Quality in Drinking Water Distribution Networks from Real-Time Direction Data
No full textModelling of contamination spread and location of a contamination source in a water distribution
network is an important task. There are several simulation tools developed, however the significant part of
them is based on hydraulic models that need node demands as input data that sometimes may result in false
negative results and put users at risk. The paper considers applicability of a real-time flow direction data based
model for contaminant transport in a distribution network of a city and evaluates the optimal number of flow
direction sensors. Simulation data suggest that the model is applicable for the distribution network of the city
of Riga and that the optimal number of sensors in this case is around 200
Characterisation of Biomass from the Wood Hydrolysate and Its Isolation with Organic and Inorganic Polycation
No full textThe hydrolysate of the hydrothermal treatment of birch sawdust in the mild alkaline conditions,
imitating industrial wastewater, was derived. An attempt to investigate the chemical and component
composition of the dry matter of the hydrolysate using FTIR, HLPC and
13
C NMR was made. The
comparative effectiveness of the isolation of wood biomass from the hydrolysate with the known
coagulants - poly(ethyleneimine) and polyaluminium chloride was assessed
Regional Hydrogeological Model of Latvia for Management of Its Groundwater Resources
No full textThe countries of the world and of the European Union are developing hydrogeological models (HM) where, by means of computer modelling, the information necessary for the groundwater management is obtained. In 1996, Riga Technical University (RTU), upon assignment of the former State Geological Survey, established regional HM REMO for the central part of Latvia. REMO does not match demands of a modern water management for the whole country, the HM plane approximation step of 4000 meters is too crude. In 2010, RTU started the project of HM that includes the whole territory of Latvia and border areas of neighbouring countries. The project is co-financed by the European Regional Development Fund. HM accounts for 25 geological layers and its plane approximation step is 500 meters. HM have to be established, during 2010-2012, as the element of the Latvian Shared Environmental Information System. It is supported by the Latvian Environment, Geology and Meteorology Centre. HM will comprise geological and hydrogeological information provided by the centre. To ensure compatibility with models of other countries, the commercial program Groundwater Vistas is used for running HM. It contains software tools applied for groundwater modelling worldwide. For the establishment and calibration of HM, innovative methods are used: the map of the ground surface elevations (digital relief) serves as a boundary condition; the aeration zone is a formal aquitard; the actual geometry of HM may not be used in the initial phase of the model establishment. The model data will be used for regional evaluation of the groundwater flow distributions, especially, in areas bordering the neighbouring countries and the Baltic Sea. HM will provide data for establishment of local HM that are used for determination of the permissible productivity of well fields, for modelling contaminant migration and for evaluation of effectiveness of measures used for restoration of groundwater resources
Administratīvi teritoriālās reformas ietekme uz pašvaldības budžeta strukturālo efektivitāti
No full textPētījuma mērķis – novērtēt administratīvi teritoriālās reformas ietekmi uz pašvaldības budžeta strukturālo efektivitāti īstermiņā. Pētījumā izmantotās metodes – salīdzināšana, relatīvie rādītāji, analītisko rādītāju atspoguļojums tabulas veidā, grafiskā metode, rādītāju aprēķināšana. Iegūtie rezultāti ļauj secināt, ka Pāvilostas novada pašvaldībai jāizvirza mērķi, kā arī jāveic finanšu līdzekļu plānošanu ilgākam laika periodam
City Branding as a Tool for Urban Regeneration: Towards a Theoretical Framework
No full textThis paper studies the concept of city branding in
general and its objectives, and examines the most common branding
strategies – the creative city and the experience city. Further on, the
paper elaborates on the notion of image-reality consistency and
explores the role of flagship developments in branding and urban
regeneration. Consequently, a strong casual link between city
branding and urban regeneration is established
Autotransporta līdzekļu motoru konstrukciju albums. I daļa: Mācību līdzeklis
No full textAutotransporta līdzekļu motoru konstrukciju albums paredzēts autotransporta specialitātes studentiem studiju priekšmeta „Autotransporta līdzekļu motoru konstrukcija” apguvei. Mācību līdzeklī dots grafiskais materiāls ar mezglu un detaļu nosaukumiem autotransporta līdzekļu motoru uzbūves apguvei
PAIC Energy Assessment Tool for Testing Buildings' Sustainability in Latvia
No full textThe role of the programme software is to provide help in filling out Building energy performance certificates, temporary certificates and supplements thereof, as well as filling out part of the relevant energy audit form
Evolution of Ontology Potential for Generation of Rules
No full textThe main purpose of this paper is to evaluate the potential of OWL (Web Ontology Language) ontologies for generation of rules. It is assumed that OWL ontology expressions can serve as a material for rule extraction. It is necessary for Semantic Web Expert System development and it is expected that such Semantic Web Expert System (SWES) will be able to process ontologies from the Web with the purpose to supplement or even to develop its knowledge base. Available publications show that the problem of rule extraction from ontologies is not investigated deeply enough
Characteristics of Mechanically Sorted Municipal Wastes and Their Suitability for Production of Refuse Derived Fuel
No full textThe article presents the results of experimental work in the first waste mechanical Pre-treatment Centre in Latvia Daibe. The goal – to detect the main parameters for sorted waste parts and to compare them with parameters stated for refuse derived fuel (RDF) in a cement plant in Latvia (Cemex). Samples were taken in four fractions - coarse, medium, fine, metal. The parameters – upper, lower heating values, moisture, ash content, S, Cl, metals were determined. Results - coarse fraction has greater potential of the production of the RDF, but reduction of its content of Cl would be necessary