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Recently, a brand new single family home was built in Sisimiut, Greenland. The building was constructed as a wooden house typical for Greenland. However, some non-traditional measures were implemented in order to reduce the energy consumption and improve indoor air quality. Assessment of the influence of these measures is essential for their implementation on a wider scale. In particular, functionality of the state of the art ventilation system is of large concern as these systems have not been commonly used for their sensitivity towards the extremely cold climate. A detailed monitoring system was installed in the house. It enables the evaluation of the indoor air quality, as well as building's energy performance. The aim of this investigation was to evaluate the performance of the newly constructed house by and compare it with the performance of identical house built in a traditional way by using a computer model. The data obtained from the measurements in the new house were used to verify the model. Significant energy savings and improvements of indoor air quality were found in the new house when compared to the traditional one. Moreover, all the extra measures have a feasible payback time despite high prices of labor and transportation to Greenland.

Recently, a brand new single family home was built in Sisimiut, Greenland. The building was constructed as a wooden house typical for Greenland. However, some non-traditional measures were implemented in order to reduce the energy consumption and improve indoor air quality. Assessment of the influence of these measures is essential for their implementation on a wider scale. In particular, functionality of the state of the art ventilation system is of large concern as these systems have not been commonly used for their sensitivity towards the extremely cold climate. A detailed monitoring system was installed in the house. It enables the evaluation of the indoor air quality, as well as building's energy performance. The aim of this investigation was to evaluatethe performance of the newly constructed house by and compare it with the performance of identical house built in a traditional way by using a computer model. The data obtained from the measurements in the new house were used to verify the model. Significant energy savings and improvements of indoor air quality were found in the new house when compared to the traditional one. Moreover, all the extra measures have a feasible payback time despite high prices of labor and transportation to Greenland.

Bygninger i arktiske klimaer kræver meget varme for at sikre et komfortabelt indeklima for brugerne. Som følge af de senere års intentioner om at spare energi er bygninger i arktiske områder (og resten af verden) blevet bedre isoleret og mere lufttætte, og den naturlige infiltration i bygningerne er blevet reduceret for at undgå varmetab og trækproblemer, ofte uden tilstrækkelig kompensation. Mange studier har vist, at ved at leve i utilstrækkeligt ventilerede bygninger øges risikoen for astma og allergi symptomer, men indeklimaet i arktiske huse er sjældent blevet undersøgt. Med hensyn til energi og indeklima er det en god idé at installere mekaniske ventilationssystemer i nye lufttætte bygninger, også selvom ventilationssystemer opsat i arktiske egne har risiko for at blive udsat for frost, der kan sætte ventilationssystemet ud af drift i længere perioder eller ligefrem beskadige det. Hovedmålet med arbejdet beskrevet i denne afhandling er: A) At give ny viden om optimal drift og ydeevne af lavenergi teknologier i arktiske egne, og B) At anskueliggøre kvaliteten af indeklimaet i boliger i arktiske egne. Den første del af afhandlingen giver et overblik over tre cases af nybyggede boliger i Grønland og Alaska. Det viste sig at ventilationssystemerne i disse boliger var enten under- eller overdimensioneret, hvilket har en stor negativ effekt på hhv. indeklimaet eller energiforbruget. En af case bygningerne havde ventilationsenheder som ikke var udstyret med frostsikring, hvilket resulterede i alvorlige isdannelser inden i varmevekslerne. I en anden case så man at den prototype varmeveksler der blev udviklet på DTU og installeret i Lav Energi Huse i Grønland havde en fejl der ikke var blevet opdaget de første 3 år den var i drift. Efter fejlen var fundet og repareret var varmeveksleren i stand til at fungere uden at fryse til og nåede en gennemsnitlig effektivitet på 69 %. I Alaska brugte tre ud af fire undersøgte ventilationssystemer recirkulation som fro, Buildings in Arctic climates require large amounts of heat to provide their occupants with a comfortable indoor environment. In recent years the intention to conserve energy has caused buildings in the Arctic (and worldwide) to become more insulated and airtight. The natural infiltration of buildings is being reduced to avoid heat loss and unpleasant air drafts, often without proper compensation. Many studies have shown that living in insufficiently ventilated spaces increases the risk for asthma and allergy symptoms. However, the indoor environment in Arctic dwellings has seldom been investigated. For energy and indoor environmental reasons it is advisable that new airtight buildings be equipped with mechanical ventilation systems with heat recovery. Nevertheless, these systems when exposed to the Arctic winter climate face the risk of frost formation, which may put the ventilation system out of order for long periods or potentially damage it. The main objectives of the work described in this thesis have been: A) to provide new knowledge about optimal operation and performance of low energy technologies in the Arctic and B) to map the indoor environmental quality in dwellings in the Arctic. The first part of this thesis provides an overview of three case studies undertaken in newly built residential buildings in Greenland and Alaska. It was found that ventilation systems in these buildings are either under or oversized which has a significant negative effect on their indoor air quality or energy use respectively. One of the evaluated buildings in Greenland had ventilation units that were not equipped with the frost protection and as a result, serious ice buildups appeared inside the heat exchangers. The prototype heat exchanger developed at the Technical University of Denmark and installed in the Low Energy House in Sisimiut had experienced an unnoticed malfunction for the first 3 years of operation. However, after repairing the heat exchanger it was capable of con

Greenlandic winters are long and cold so living inside the heated and properly ventilated space requires quite some energy. It is assumed that in mechanically ventilated buildings, significant amounts of energy for heating can be conserved by adjusting the ventilation flow rates according to actual demand of the occupants. Traditional solutions available on market consist of controller and sensors in the living space detecting the occupancy and activity (movement sensors, CO2 sensors, Humidity sensors, etc.). The controller needs to be programmed and maintained by an expert and sensors need to be hardwired to the controller. In Greenland where price of the labor is very high and availability of experts limited the installation of such control system becomes unacceptably expensive, particularly in case of renovation of existing buildings. One possible solution to the above is to introduce wireless sensor network (WSN) technologies. The design of a prototype wireless monitoring and control system is demonstrated in the new dormitory Apisseq in Sisimiut, Greenland. The existing mechanical ventilation was running at a constant air volume even during unoccupied hours which resulted in a very high heat demand. It was estimated that installing the WSN system will bring annual savings of 1,600 € at the investment of 8,000 €. This paper describes the initial setup of the system and discusses its advantages and drawbacks.

A new student accommodation for engineering students “Apisseq” was built in the town of Sisimiut, Greenland in 2010. Its purpose is not only to provide accommodation for students. Thanks to its complex monitoring system it enables researchers to evaluate the building’s energy performance and indoor air quality (IAQ) as well as performance of some single components. In summer 2012 a blower door test was performed on all 37 living units out of which 33 are identical single room flats and 4 are larger double room flats. The purpose was to evaluate the air tightness of the envelope and to find out how much the flats differ from each other in terms of air tightness. The overall average specific leakage measured was w50 = 2.05 l/(s·m2) of heated floor area corresponding to an air change n50 of 2.96 h-1. Furthermore, the results showed that the difference between the most and the least tight flat is as high as 400%. This result is without consideration of one particular flat which had the extreme result of being 940% as leaky as the unit with the highest air tightness. The reasons for such poor air tightness are lack of the installation gap between the vapour barrier and the inner wall, and insufficient connections of the vapour barrier to the interior walls as explained in the paper. The large variation in results can be attributed to insufficient consideration of the importance of airtighness during construction of some parts of the building – despite of an intent to make a rather air tight building.

A new dormitory for engineering students “Apisseq” was built in the town of Sisimiut, Greenland in 2010. Its purpose is not only to provide accommodation for students. Thanks to its complex monitoring system it enables researchers to evaluate the building’s energy performance and indoor air quality (IAQ) as well as performance of some single components. Some of the installed technologies (balanced mechanical ventilation with heat recovery or solar collectors) are not commonly used in the current Greenlandic building stock. Therefore evaluation of their performance under local conditions is essential for further use and development. The first year of operation has disclosed some errors made during the design process and construction phase which have negative effects on the energy performance and IAQ. The heat demand in 2011 was 26.5% higher than expected. One of the main causes of the extra heat consumption is the fact that the ventilation system was over-dimensioned, and although it is running on the lowest fan power it maintains 1.1 ACH in the building. Reduction of the air flows and better frost protection of the heat exchangers are important issues to be dealt with in order to decrease the heat demand. This paper describes the building and how it is evaluated after the first year of operation, and it explains some of the revealed problems.

In cold arctic regions people usually spend over 70% of their time indoors. The effect of poor indoor air quality on occupants’ health and comfort is therefore considerable. Dwellings in Greenland consume very large amounts of energy (in average over 370 kWh/year per m2) and in addition, they provide their occupants with poor indoor air quality. A questionnaire survey was performed in the town of Sisimiut-Greenland, which with its location and population represents Greenlandic conditions quite well. The aim of the survey was to investigate the energy consumption and indoor air quality in arctic dwellings and to study the influence of occupant behaviour of people living in arctic climates on energy consumption and indoor air quality. The results have shown that the average electricity consumption is 20% higher than in DK, ventilation systems are insufficient and that the inhabitants often experience cold discomfort in their homes due to their window opening behaviour (to compensate the lack of ventilation) and the age and deficient construction of the buildings. On the basis of the survey responses, some 80 dwellings were selected for further investigation. Physical measurements of the indoor air quality and observations of occupant behaviour will be performed in the selected dwellings.

The aim of this article is to present and disseminate the experience gained from a low‐energy house in Sisimiut, Greenland, over the 5 years of operation since its inauguration in April 2005. The house was designed to test and present new low‐energy technologies in the Arctic climate and to improve sustainability in Greenlandic buildings. The article presents some measurements, analyses and comparisons of theoretical simulations, and also some steps which were taken to improve the house with impacts on the energy consumption. The results include energy consumption, temperatures, and solar heating production. Also presented are the results of several investigations carried out in the house, such as blower‐door tests and inspection of the ventilation system. The initial target for the heating demand of the house was that it should be restricted to 80 kWh/(m2⋅a), but in reality it has varied over the past 5 years from 139 to 150 kWh/(m2⋅a). Currently the house is on the way to present a good energy solution, and the annual energy consumption for heating in 2010 was 90 kWh/m2.

In 2005, a low energy house was inaugurated in Sisimiut, Greenland. The house and the plans with it were presented at the third International Building Physics Conference in 2006. The house is characterised by having a highly insulated building envelope which is almost free of thermal bridges, advanced windows, a ventilation system with heat recovery, and a solar collector that supplies a significant proportion of the domestic hot water. A very ambitious target was set for the annual energy consumption for heating, which was less than half of the value for permissible heat consumption according to the Greenlandic Building Regulations. The house has been the base of a number of research and student activities which have studied the house and evaluated how well it has performed. These investigations have clarified how the weather influences the hygrothermal performance of the house, and whether the house matches the expectations regarding low energy consumption and a high indoor climatic standard. The house did not meet the anticipated low target for energy consumption, and some reasons have been found which could explain why. Insufficient air-tightness of the building envelope, malfunction of some building services, insufficient insulation of ventilation ducts, and higher indoor temperatures than anticipated were among the main reasons.

A low-energy house has been built in Sisimiut, Greenland, five years ago. An ambitious target was set for its low energy consumption for heating: 80 kWh/(m2∙a). But unfortunately, the house has used more energy than planned, approximately 140 kWh/(m2∙a). Although higher than anticipated, this is still for Greenland a very low energy consumption. The purpose of the work presented in the paper has been to analyze the energy consumption of the house and to understand why it was different than anticipated. One significant lesson learned is that the house was not built with sufficient air-tightness and that it was one of the main reasons for its higher energy consumption.

Cieľom práce je návrh uchopenia a posúvania vysielacej antény v automobile a meranie prenosu signálu pri zmenách rôznych parametrov: obsadenosť vozidla, poloha sedadiel, vzdialenosť antén. Vysielacia a prijímacia anténa bude tvorená otvoreným ústim vlnovodu. Prenos signálu bude meraný vektorovým sieťovým analyzátorom ZVA 67 od firmy Rhode&Schwarz., The aim of this work is design how to grip and change position of transmitting antenna in vehicle and measurements of signal changes due to different parameters, such as people in vehicle, position of seats and range between antennas. Transmitting and received antenna is design as open-ended waveguide. Signal transmission is measured by vector network analyzer ZVA 67 from Rhode&Schwarz.

Cieľom práce je návrh uchopenia a posúvania vysielacej antény v automobile a meranie prenosu signálu pri zmenách rôznych parametrov: obsadenosť vozidla, poloha sedadiel, vzdialenosť antén. Vysielacia a prijímacia anténa bude tvorená otvoreným ústim vlnovodu. Prenos signálu bude meraný vektorovým sieťovým analyzátorom ZVA 67 od firmy Rhode&Schwarz., The aim of this work is design how to grip and change position of transmitting antenna in vehicle and measurements of signal changes due to different parameters, such as people in vehicle, position of seats and range between antennas. Transmitting and received antenna is design as open-ended waveguide. Signal transmission is measured by vector network analyzer ZVA 67 from Rhode&Schwarz.

Cieľom práce je návrh uchopenia a posúvania vysielacej antény v automobile a meranie prenosu signálu pri zmenách rôznych parametrov: obsadenosť vozidla, poloha sedadiel, vzdialenosť antén. Vysielacia a prijímacia anténa bude tvorená otvoreným ústim vlnovodu. Prenos signálu bude meraný vektorovým sieťovým analyzátorom ZVA 67 od firmy Rhode&Schwarz., The aim of this work is design how to grip and change position of transmitting antenna in vehicle and measurements of signal changes due to different parameters, such as people in vehicle, position of seats and range between antennas. Transmitting and received antenna is design as open-ended waveguide. Signal transmission is measured by vector network analyzer ZVA 67 from Rhode&Schwarz.

Cieľom práce je návrh uchopenia a posúvania vysielacej antény v automobile a meranie prenosu signálu pri zmenách rôznych parametrov: obsadenosť vozidla, poloha sedadiel, vzdialenosť antén. Vysielacia a prijímacia anténa bude tvorená otvoreným ústim vlnovodu. Prenos signálu bude meraný vektorovým sieťovým analyzátorom ZVA 67 od firmy Rhode&Schwarz., The aim of this work is design how to grip and change position of transmitting antenna in vehicle and measurements of signal changes due to different parameters, such as people in vehicle, position of seats and range between antennas. Transmitting and received antenna is design as open-ended waveguide. Signal transmission is measured by vector network analyzer ZVA 67 from Rhode&Schwarz.

Cieľom práce je návrh uchopenia a posúvania vysielacej antény v automobile a meranie prenosu signálu pri zmenách rôznych parametrov: obsadenosť vozidla, poloha sedadiel, vzdialenosť antén. Vysielacia a prijímacia anténa bude tvorená otvoreným ústim vlnovodu. Prenos signálu bude meraný vektorovým sieťovým analyzátorom ZVA 67 od firmy Rhode&Schwarz., The aim of this work is design how to grip and change position of transmitting antenna in vehicle and measurements of signal changes due to different parameters, such as people in vehicle, position of seats and range between antennas. Transmitting and received antenna is design as open-ended waveguide. Signal transmission is measured by vector network analyzer ZVA 67 from Rhode&Schwarz.

V zadání bakalářské práce je uvedena analýza zapojení napájecích zdrojů v OrCAD. Na základě této analýzy, jsou vybrány nejvhodnější napájecí zdroje, které jsou modifikovány na parametry 2x 0-30V/ 0-3A. Uvedená zapojení napájecích zdrojů jsou testována simulacemi na počítači a navržena koncepce digitálního řízení. Digitální řízení napájecího zdroje je navrženo prostřednictvím digitálních potenciometrů, které jsou ovládány mikroprocesorem. K mikroprocesoru, jsou dále připojeny měřící jednotky pro měření výstupního napětí a proudu. K napájecímu zdroji, je možno s výhodou připojit klávesnici a displej pro pohodlnou komunikaci. Na základě výše uvedeného návrhu je vyroben prototyp a navržena metodika testování zdroje. Aplikací metodiky testování prototypu napájecího zdroje jsou získány výsledky měření, které jsou porovnány s parametry simulací na počítači a ověřeno digitální řízení., The award of the thesis is an analysis of the involvement of power supplies in OrCAD.Based on this analysis, the best are selected, power supplies, which are modified on the performance of 2x 0-30V / 0-3A. The connection of power supplies are tested incomputer simulations and proposed the concept of digital control. Digital control power supply is designed by digital potentiometers that are controlled by a microprocessor. The microprocessor is also connected to the measuring unit for measuring the output voltage and current. The power supply is advantageously possibleto connect a keyboard and display for convenient communication. Based on the above proposal is to prototype and test a methodology for resources.Applying the methodology of testing a prototype power source are obtainedmeasurement results are compared with parameters on a computer simulation and verified by digital control.

Uvedená diplomová práce rozebírá problematiku optických laserových dálkoměrů ve skutečném přenosovém prostředí. Popisuje jednotlivé díly optických laserových dálkoměrů jejich vlastnosti a principy v návaznosti na jejich výkonovou bilanci. V práci jsou uvedeny základní optické vlastnosti čoček používaných ve vysílači a přijímači. Samostatná kapitola je věnována metodě tranzitního času a faktorům ovlivňujícím měření. Součástí diplomové práce je rozbor poměrné směrové odrazivosti. V závěru diplomové práce jsou uvedeny praktické laboratorní výsledky měření poměrné směrové odrazivosti různých materiálů a barev. Na základě naměřených hodnot byl ověřen výkonový úrovňový diagram dálkoměru., The thesis analyzes the optical laser range finders in real propagation environments. Itdescribes the various parts of optical laser range finders their properties and principles in relation to their performance balance. The paper presents the basic optical properties of lenses used in the transmitter and receiver. A separate chapter is devoted to the transit time method and factors influencing the measurement. The proportional directional reflectance analysisis a part of the thesis. In conclusion, the thesis contains the practical laboratory measurements of the relative directional reflectance of different materials and colors, and verification of the power level diagram.