<a href="/v5/viewer/files/Default_s.aspx?gKey=snt8d08s&gInitPage=1">Scanvac 1 N e ws le t t e r Grand centenary celebr</a> ation of Swedvac at Stockholm Town Hall read more on page 9 1/2009 SCANVAC - SCANDINAVIAN FEDERATION OF HEATING, VENTILATION AND SANITARY ENGINEERING ASSOCIATIONS IN DENMARK,FINLAND, ICELAND,NORWAY AND SWEDEN
<a href="/v5/viewer/files/Default_s.aspx?gKey=snt8d08s&gInitPage=2">Scanvac Sida 2 contents 2 3 3 4 5 6 8 8 9 10 New S</a> ecretary General of Norvac New Secretary General of Swedvac Cold climate HVAC In Greenland Effstock 2009 proved thermal energy storage a key technology for the future Finnish Qualification of Professionals in Building, HVAC and Real Estate Sector Doctorate Theses Press items Awards Grand centenary celebration of Swedvac at Stockholm Town Hall HVAC Calender New SecreTary GeNeral of Norvac Thor-Jostein Egeland has been appointed Secretary General of the Norwegian Society of Heating, Air Conditioning and Sanitary Engineers from January 1st this year. THoR-JoSTEIN EGElAND STARTED working for Norvac in May 2007 as a developer of the organization. He has previously been working as director of the Norwegian Market Analysis Organization. Since his start in 2007 Thor-Jostein Egeland has focused on further developing communication strategies and role of Norvac, both internally and externally. - We have learnt much about our members and how to facilitate the one-to-one dialog with our members, says Egeland. He succeeds Leif Amdahl who has been secretary general of Norvac since 2003. N e ws le t t e r Editor: Signhild Gehlin Layout: Anne Strömer SWEDVAC Vasagatan 52 SE-111 20 Stockholm, Sweden Tel: 46 8 791 66 80 Fax: 46 8 660 39 44 E-mail gehlin@siki.se www.scanvac.net Deadlines: 1 April and 1 November ISSN 0804-0745 There is no copyright on Scanvac Newsletter Photo: Norvac SCANVAC 1/2009 contents 2 3 3 4 5 6 8 8 9 10 New Secretary General of Norvac New Secretary General of Swedvac Cold climate HVAC In Greenland Effstock 2009 proved thermal energy storage a key technology for the future Finnish Qualification of Professionals in Building, HVAC and Real Estate Sector Doctorate Theses Press items Awards Grand centenary celebration of Swedvac at Stockholm Town Hall HVAC Calender New SecreTary GeNeral of Norvac Thor-Jostein Egeland has been appointed Secretary General of the Norwegian Society of Heating, Air Conditioning and Sanitary Engineers from January 1st this year. THoR-JoSTEIN EGElAND STARTED working for Norvac in May 2007 as a developer of the organization. He has previously been working as director of the Norwegian Market Analysis Organization. Since his start in 2007 Thor-Jostein Egeland has focused on further developing communication strategies and role of Norvac, both internally and externally. - We have learnt much about our members and how to facilitate the one-to-one dialog with our members, says Egeland. He succeeds Leif Amdahl who has been secretary general of Norvac since 2003. N e ws le t t e r Editor: Signhild Gehlin Layout: Anne Strömer SWEDVAC Vasagatan 52 SE-111 20 Stockholm, Sweden Tel: 46 8 791 66 80 Fax: 46 8 660 39 44 E-mail gehlin@siki.se www.scanvac.net Deadlines: 1 April and 1 November ISSN 0804-0745 There is no copyright on Scanvac Newsletter Photo: Norvac SCANVAC 1/2009
<a href="/v5/viewer/files/Default_s.aspx?gKey=snt8d08s&gInitPage=3">Scanvac Sida 3 New SecreTary GeNeral of Swedvac Si</a> gnhild Gehlin appointed Secretary General of the Swedish Society of HVAC Engineers, Swedvac, from August the 1st this year. SIGNHIlD GEHlIN fINISHED her education as a civil engineer in 1996 and continued as a researcher in water resources engineering at Luleå University of Technology (LTU). She started working for Swedvac in 1999 as part time technical secretary, when she was still a research student at LTU. After her dissertation on thermal response test – a measurement method for determining the capacity of energy wells in field – in 2002, Signhild has worked full time at Swedvac as technical secretary. January 2006 - April 2009 she was chief editor of the Swedvac monthly technical magazine Energi & Miljö (Energy & Environment). Signhild is the first woman to be appointed Swedvac secretary general, and succeeds Bengt-Göran Jarefors,who is retiring after 13 years as Swedvac secretary general. Signhild Gehlin is 38 years old. Coldclimate HVAC in Greenland cold climate hvac 2009 in Sisimiut, Greenland, was a great success and showed that the technical width of building in cold areas has reached a very high level. It also shows the importance of cooperation between research centres and private companies to reach the goals. . Participants from 12 countries attended Cold Climate HVAC in Greenland. The first day covered energy and building technology for people in arctic regions. The second day started with issues on low energy buildings and during the third day the theme was building construction and facilities management. All in all it was a highly interesting conference with many excellent presentations covering some very exciting issues. It became very visual that the technical width within the field of buildings in cold climate in the world has reached a very high level. henning Grønbæk, exhausto a/s Bent michael Nielsen, Grontmij | carl Bro SCANVAC 1/2009 Picture: exhausto Photo: iNGar liNdholm
<a href="/v5/viewer/files/Default_s.aspx?gKey=snt8d08s&gInitPage=4">Scanvac Sida 4 Effstock 2009 proved thermal energy</a> storage a key technology for the future effstock 2009 – the 11th international conference on thermal energy storage, hosted by swedvac in stockholm June 14-17 – turned out a great success. 380 participants from 32 countries attended the conference and took part of the 170 scientific presentations, the exhibition and lunch forums. THE fIRST DAy began with a technical overview offering a useful orientation of the three main storage technologies covered by the conference. Sensible heat storage, including storage of heat and cold in the underground, such as aquifers, rock and other ground material, represented about half the presentations during the conference. The second half of the conference presentations dealt with latent and thermochemical heat storage in large and small scale. Aquifer applications – 30 years of R&D Based on experience and results of 30 years of R&D and demo projects, aquifer energy storage (ATES) is now a viable and reliable technology. ATES projects have to be designed for favourable hydro-geological and chemical site conditions taking into account results and simulations. New large scale projects have been commissioned (e.g. Stockholm – Arlanda) Thermal response test – a success story A total of 17 presentations covered the measurement method Thermal response test (TRT) for borehole thermal energy storage system. The method has become popular since the beginning of its use in the 1990’s due to its educational virtues. It is evident that TRT is now an accepted and well understood technology in many countries, and has become a standard procedure for larger installations. 4 There are however still unresolved questions concerning groundwater issues and the vertical distribution of thermal conductivity in the underground. TRT is also used as a method to evaluate borehole collectors, geological layers as well as to determine groundwater flow and has clearly proved its role as a success story within IEA ECES collaboration. Snow & ice applications Four papers were presented on snow and ice applications in Japan. Japan shows an impressing development – almost 200 snow storage systems for space cooling as well as agricultural applications – although Japan has less favourable conditions than North of Europe, and North America. One paper presented the use of borehole thermal energy storage (BTES) for melting of snow at Arlanda airport. Two years of testing was reported. Solar Applications Thermal energy storage is essential in achieving good solar fraction for heating. The addition of heat pumps could increase the solar fraction further. Several economic combinations of water, PCM, ATES and BTES were applied for both diurnal and seasonal storage. Presented projects mainly originated from Germany, but also from Spain, Sweden and Switzerland. A high temperature PCM for Solar thermal electrical generation in Israel was also presented. High temperature applications need cost reduction Several high temperature applications were presented, and of these, the most discussed application was on Concentrated Solar Power Most important issue in this field is cost reduction of the systems. For the future development it is crucial to reduce cost of storage material by using recycled material, and finding new suitable materials, and to reduce system costs by improving storage design (enhancing thermal conduction). Thermochemical storage – a young area Thermochemical applications are still on the level of basic research on materials – both theoretical and experimental research. Several presentations included ideas that will not be economically feasible within the near future. Hence we must not forget the economic boundary conditions in identifying the most promising applications. It was encouraging to observe that several young presenters are working in this field. Sustainable comfort cooling A special session of sustainable comfort cooling included a state-of- the art review of Phase changing materials (PCM) for cooling. Phase change slurry (PCS) is a new development to challenge “desert” climate SCANVAC 1/2009
<a href="/v5/viewer/files/Default_s.aspx?gKey=snt8d08s&gInitPage=5">Scanvac Sida 5 in India. The session covered use o</a> f microencapsulated PCM in building materials, like concrete and plasters as well as hyrbrid ground coupled heat pump system analysis on various operation schemes. Case studies show creativity The conference had an aim to enhance case studies and it was clear that site specific and system specific solutions should not be overlooked. It is a strong simplification that energy storage is all about underground thermal energy storage, phase change materials and building heating and cooling. Examples show applications such as using abandoned mines and caverns for storage,using building mass for short term storage, and applying underground thermal energy storgae for short term storage of waste heat. Models & Design tools Validations and improvements to sensible thermal energy storage models were reported. In one case, moisture in the insulations was identified as the cause of discrepancies between model and actual performance. The difficulty of controlling thermally activated building systems was highlighted by one presenter. A dynamic simulation of Adiabatic CAES was reported; preliminary results show the efficiency is correlated to the size of the store Improvements were shown to ground heat exchanger models. Heat pump models were also reported though still in progress. Preliminary investigation of “black box” type PHoToS: INGAR lINDHolM ground heat exchanger model was reported. One intended application is control of auxiliary heat sinks/sources along with the ground heat exchanger. The business exhibition held in conjunction with the conference hosted 30 companies and organisations related to energy storage. The exhibition was frequently visited by the conference participants and was a subject of great content to all parties. fruitful lunch forums As a complement to the strictly scheduled scientific presentations, a series of lunch forum, open to the public, were arranged during the three conference days. These forums gave opportunity to more informal presentations of energy storage presentations and case studies aiming to create of a fruitful dialog between the presenters and the audience. All seven lunch forums were well-attended and popular. Next Stock-conference will be held in Lleida, Spain in 2012. The name of the conference will be Innostock as the focus will be of innovation within thermal energy storage. signhild Gehlin fiNNiSH QualificaTioN of ProfeSSioNalS iN BuildiNG, Hvac aNd real eSTaTe SecTor fISE STATES THE personal qualification levels within the building sector, HVAC and real estate field, and collects data in a register that will secure the quality of buildings. FISE develops and maintains a national qualification register in which qualified actors are easily found by constructors, employers, etc. FISE also maintains the Construction Error Data Base. The Construction Error Data Base secures dissemination of information on qualitative and safe building, promotes development of buildings and prevents mistakes and environmental hazards. hannu sipilä secretary General the hvac assosiation of finland, sulvi ry SCANVAC 1/2009 5
<a href="/v5/viewer/files/Default_s.aspx?gKey=snt8d08s&gInitPage=6">Scanvac Sida 6 doctorate Thesis Gabriel Bekö secti</a> on for indoor environment, department of civil engineering, technical university of denmark removal of Particles from the supply air of ventilation systems avoiding the formation of sensory Pollution source: delivery of clean air to Building occupants aBstract Used ventilation filters can act as sources of strong sensory pollution. The pollutants emitted from loaded particle filters may include irritating products of chemical reactions occurring on the filter surfaces. Most likely oxidation reactions, especially those driven by ozone, seem to play an important role. Sensory pollutants emitted from used filters can have significant adverse impact on occupant performance. Therefore, removal of particles from the supply air of ventilation systems without the subsequent emission of pollutants into the airstream seems to be essential. Correct maintenance of filter banks, including filter replacement in due time, is also important. The aim of this work was to gain more knowledge leading to a better understanding and solving a long recognized indoor environmental problem. The thesis deals with three core areas. Firstly, experiments were conducted to obtain better insight into the chemical processes occurring on the surfaces of used ventilation filters. Secondly, an economic evaluation was made to determine the impact of decreased occupant productivity caused by pollution from used filters on the overall costs and economic benefits associated with filtration. Finally, an experiment was designed to test the effect of different particle filters, activated carbon filters and their combinations on the perceived air quality after several months of continuous use. A commercially available HVAC filter that has low emissions of pollutants, even after substantial time in service, would mean a step forward towards finding an engineering solution to the problem. Additional measurements examined the effect of different pressure sensing techniques and several modifications of an air handling unit on the accuracy of the measurements of pressure drop over ventilation filters. Used and new filters were found to initially remove large amounts of ozone from the air that passed through. The initial ozone removal efficiency (~50%) decreased within an hour to a low and constant value (<15%). Exposure of the filter samples to different static environments promoted the regeneration of their ozone removal capabilities. The ozone removal by used filters is assumed to occur in the first place due to chemical reactions between ozone and the organics associated with the particles captured on the filter surfaces. The ratio of submicron particle concentrations downstream of the filter to the concentrations upstream of the filter was higher when ozone was added to the airstream through the filter sample. Such a result is an underlying evidence for the generation of low volatility oxidation products on filter surfaces at the presence of ozone. Results of sensory assessments support the assumption that oxidation processes on filter surfaces contribute to the sensory pollution downstream of used filters. The estimates of costs and the corresponding monetary benefits of particle filtration indicated that using particle filtration can lead to substantial reductions of costs in connection with occupants’ mortality and morbidity, building cleaning and cleaning of HVAC systems. Although the cost-benefit ratio depends on the perspective of the stakeholder, the savings attributable to filtration would always exceed the direct costs. However, the present study showed that economic losses resulting from even a small decrease in productivity as a consequence of sensory pollutants emitted from used ventilation filters have the potential to substantially overwhelm the annual benefits of filtration. The quality of air passing through various filter combinations was perceived most acceptable when an activated carbon filter was placed downstream of the particle filter during its 5 months long service time. A stand-alone fiberglass bag filter that incorporated activated iv carbon achieved similar results at negligible increase in pressure drop during the time in service. Moreover, this filter was found to remove considerable amount of ozone from the supply air, which is beneficial from the perspective of occupants’ health. For correct maintenance of ventilation systems and filters within, accurate determination of filter pressure drops is important. The results of the experiments indicate that bends or dampers directly upstream of the filter housing, the type of pressure sensing device as well as the location of the up- and downstream static pressure sensors may significantly influence the accuracy of the pressure drop measured across ventilation filters. 8 SCANVAC 2/2008
<a href="/v5/viewer/files/Default_s.aspx?gKey=snt8d08s&gInitPage=7">Scanvac Sida 7 doctorate Thesis MARI-lIIS MARIPUU </a> Building services engineering chalmers university of technology Göteborg, sweden demand controlled ventilation (dcv) systems in commercial buildings - functional requirements on systems and components aBstract Demand controlled ventilation (DCV) is considered as an energy efficient solution for air-based cooling and indoor air quality control. Considerable energy savings can be achieved when the airflow rate is continuously adapted to the actual load condition. However, in order to assure the desired performance of the system, it is essential to know the requirements that the DCV system and its components should fulfil. The objective of this work has been to clarify the requirements for a well functioning DCV system. This includes cooling performance as well as sensor based air quality control. The work is based on theoretical analysis, field measurements of occupancy and system performance as well as laboratory investigations of DCV supply air diffusers and sensors for air quality control. This thesis shows that it is possible to implement in existing as well as in new buildings an uncomplicated DCV solution that requires no active control dampers in the duct system. This, however, requires variable supply air diffusers with good airflow control properties and with a low noise generation even at a high pressure drop over the device. Also, in cooling applications the devices must provide a comfortable airflow pattern in the room within the entire airflow range and with low supply air temperature. In addition, the duct system must manage the wide airflow range, including the design minimum supply air temperature for cooling, with negligible heat gains. Tests carried out with such a DCV configuration show that high requirements set on the system components can be fulfilled. An additional focus in this thesis is the application of DCV systems for air quality control. This requires sensors that can monitor the air quality and/or pollution to control the hygienic ventilation rate. Quantitative requirements for such sensors have been developed based on ventilation guidelines and standards. A detailed sensor study was carried out with a number of CO2-sensors and mixed-gas sensors. Results show that, depending on the requirement, several tested CO2-sensors could fulfil the established requirements set on sensors. However, the application of the tested mixed-gas sensors for ventilation control is undecided. It is not clear how the output of mixed-gas sensors should be interpreted. Another limitation comes from the lack of available standards describing acceptable concentrations for many common air contaminants for non-industrial buildings. Finally, this thesis also provides some information on the actual occupancy patterns in a commercial building in operation. One year monitoring in an office building indicates that during 90 % of the time the simultaneously occupancy in the building is equal to or less than about 53 %. doctorate Thesis Magdalena lundh faculty of science and technology, uppsala university, sweden domestic heating with solar thermal: studies of technology in a social context and Social Components in Technical studies aBstract Research in solar heating has traditionally focused solely on increasing the system efficiency by improving the technical components. In this thesis the technical methodology and system boundaries are widened to connect the technical aspects with market actors that are highly influential on the implementation of solar technology. The research was focused on how social aspects can be brought into technical studies to improve the understanding of solar heating, and how solar thermal technology can be optimized in a larger energy system. Both heat storage and different system solutions have been investigated. The thesis is built on a number of sub-projects exploring different aspects of solar heating. Improved components and system configurations may result in higher fractional energy savings and thereby make solar energy go from a marginal contribution to be the main energy supplier. Both components and systems are considered in this thesis. The solar heating technology has been shown to work well, also in unique system solutions. Technical possibilities with mediumsized stores for single-family houses and seasonal stores for residential areas are presented. Methods to bring studies of technology and actor studies together are also proposed; domestic hot water use has been modelled based on time-use data,while a multifaceted market situation, in which new system solutions must find their way, has been described by the solar and pellet industries. The complexity of assessing installation and use of a particular heating system in relation to the overall energy system is also discussed. Overall, this thesis shows that successful use of solar heating does not only come down to proper technical solutions, but also depends on the interaction between technology and market actors. A widened perspective, including the social context in which the heating system appears, is then essential. This thesis constitutes a step in that direction. SCANVAC 1/2009
<a href="/v5/viewer/files/Default_s.aspx?gKey=snt8d08s&gInitPage=8">Scanvac Sida 8 Press items NoRWAy In a report from</a> the Norwegian Technology Council to the Norwegian Government, the Government is urged to work for Statoil Hydro to obtain 5% of its investments tied to renewable energy and reduction of its emissions of green house gases by 30% before 2020. fINlAND Finnish energy certificate programs. The HVAC Association of Finland has prepared energy certificate programs adjusted for Finnish legislation. The three programs all result in the same energy certificate. Architects can certify new constructions when they are completed, but usually it is the HVAC engineer/designer who makes the energy certificate. The building manager can also give energy certificates in connection with investigations of the energy consumption of the previous year. The person qualified to make energy certificates can also give energy saving proposals. Johnny v andersson receives rehva Professional award REHVA PRofESSIoNAl AWARD is an award given once every year to a distinguished engineer or scientist within the member countries of Rehva, the European Federation of HVAC Associations. This year the award was granted Mr Johnny V Andersson, Sweden. Johnny V Andersson was awarded for his distinguished efforts for improving energy efficiency and indoor climate in buildings. During many years, Johnny V Andersson has worked within this field in Swedish and international projects for EU, IEA, Rehva and Ashrae. Swedvac Prize THE 2009 SWEDVAC Prize for outstanding diploma theses and academic theses were presented at the Swedvac General Assembly in Stockholm, June 16th . The Grand Swedvac Prize was awarded Stefan Sandgren for his diploma thesis ”Energy efficiency and its impact on indoor environment – a case study on an office building” Stefan Sandgren wrote his diploma thesis at Malmö University. The smaller prize was given to Henrik Stellnert, Royal Institute of Technology, Stockholm, for his diploma thesis on assessment of an exhaust air curtain. PHoTo: INGAR lINDHolM PHoTo: AlExANDER fARNSWoRTH
<a href="/v5/viewer/files/Default_s.aspx?gKey=snt8d08s&gInitPage=9">Scanvac Sida 9 ...................................</a> ............................................................................................................. ................................................................................................................................................ ................................................................................................................................................ ................................................................................................................................................ ................................................................................................................................................ ................................................................................................................................................ ................................................ ................................................................................................................................................ ................................................................................................................................................ Grand centenary celebration of Swedvac at Stockholm Town Hall THE SWEDISH SoCIETy of HVAC Engineers, Swedvac, celebrated its 100 years anniversary with a grand gala dinner in the magnificent Blue Ahll of the Stockholm Town Hall. The gala dinner took place in the evening of June 16th , after the Swedvac general assembly. 730 guest from a total of 32 countries were gathered in the Blue Hall for the celebrations, among them representatives from several sister organisations in Scandinavia and Europe, as well as participants from the Effstock 2009 international energy storage conference. During the gala dinner Mr Johnny V Andersson was presented the Rehva Professional Award by Rehva Secretary General Olli Seppänen. The first Rolf Ulfvengren Memorial Award for most innovative paper on Phase Change Materials was also distributed during the dinner celebrations. The award was granted Mr Joerg Vaschull from Germany. The gala dinner guests were treated with musical entertainment, illustrating the 100 years history of Swedvac, as well as traditional Swedish organ music and folk music falcetto song. ................................................................................................................................................ ................................................................................................................................................ ................................................................................................................................................ ................................................................................................................................................ ................................................................................................................................................ ................................................................................................................................................ ................................................................................................. ................................................ ................................................................................................. 9 PHoTo: AlExANDER fARNSWoRTH
<a href="/v5/viewer/files/Default_s.aspx?gKey=snt8d08s&gInitPage=10">Scanvac Sida 10 HVAC Calendar scandinavia l Nordby</a> gg 2010. Stockholm, Sweden, 23-26 March 2010. More info: www.nordbygg.com World l EU PVSEC – Hamburg, Germany, September 21-24 2009. More info: www.photovoltaic-conference.com l SWC 2009 – Johannesburg, October 11-14 2009.More info: www.swc2009.co.za l Clean Energy Power. Stuttgart, Germany, 25-27 February 2010. More info: www.energie-server.de l Mostra Convegno Expocomfort 2010. Milan, Italy, 23-27 March 2010. More info: www.mcexpocomfort.it l Clima 2010. Antalya, Turkey, 9-12 May 2010.More info: www.clima2010.org SCANVAC Denmark DANVAK The Danish Society of HVAC Engineers Founded in 1945 Number of Members 2500 President: Jørn Simonsen Lautrupvang 1B, DK 2750 Ballerup, Denmark Tel: +45 36 36 90 60 Fax: +45 36 70 20 71 E-mail: info@danvak.dk www.danvak.dk Finland FINVAC The Finnish Society of HVAC Engineers Founded in 1930 Number of Members 6000 President: Olli Seppänen Sitratori 5, FIN-00420 Helsinki Tel: +358 9 56 60 090 Fax: +358 9 56 60 0956 E-mail: sulvi@suomenlvi-liitto.fi www.finvac.org Iceland ICEVAC The Icelandic Society of HVAC Engineers Founded in 1986 Number of Members 400 President: Björn Karlsson Ystibær 11, IS-110 Reykjavik, Iceland Tel: +354 587 06 60 Fax: +354 587 41 62 E-mail: lafi@simnet.is www.lafi.is Norway NORVAC The Norwegian Society of HVAC Engineers Founded in 1924 Number of Members 3100 President: Bent Myhre Kjølberggata 31, inng. Brinken, P.O.B 2843, Tøyen, N-0608 Oslo, Norway Tel: +47 22 70 83 00 Fax: +47 22 70 83 02 E-mail: vvs@vvs-foreningen.no www.vvs-foreningen.no Sweden SWEDVAC The Swedish Society of HVAC Engineers Founded in 1909 Number of Members 7200 President: Östen Innala Vasagatan 52, SE-111 20 Stockholm, Sweden Tel: +46 8 791 66 80 Fax: +46 8 660 39 44 E-mail: info@emtf.se www.emtf.se BALTVAC Estonia ESTVAC The Estonian Society of HVAC Engineers,EKVü Founded in 1991 Number of members 130 President: Teet Tark Rävala pst. 8-B211, 101 43 Talinn, Estonia Tel: +372 6604 524 E-mail: ekvy@hot.ee www.hot.ee/ekvy Latvia LATVAC The Latvian Society of HVAC Engineers President: Egils Dzelzitis SGUTIS/AHGWTEL, Vagonu ula 20, LV-1009 Riga, Latvia Tel: +371 7 50 66 50 Fax: +371 9 20 55 85 E-mail: egils.dz@latipa.apollo.lv Next stop for material deadline 1 november Lithuania LITVAC The Lithuanian Society of HVAC Engineers President: Stasys Sinkunas LITES-Lithuanian, Thermotechnical Engineering Society Donelaicio st. 20-227, LT-3000 Kaunas Tel: +370 7 300 436 Fax: +370 7 321 449 E-mail: lites@mf.ktu.lt
