scholarly journals Moisture related challenges in the Greenlandic building sector – results from a survey

2021 ◽  
Vol 2069 (1) ◽  
pp. 012072
Author(s):  
E J de Place Hansen

Abstract The building industry is booming in the larger cities of Greenland; there is a need for housing, and the building stock is in urgent need of renovation, mainly due to the combination of extreme weather conditions and the lack of tradition to maintain buildings. The harsh climate with short summers and long periods of cold weather combined with occasionally high wind speed and precipitation makes it difficult to prevent moisture during the construction phase, causing high drying costs. These challenges highlight the need for guidelines on how to handle moisture especially in the construction phase, both at renovation or when erecting new buildings. To prepare the guidelines, a survey was carried out aimed at building professionals in Greenland. Focus was on identifying construction work challenged by the conditions in Greenland including geography and seasons. The feedback gave an overview on the main challenges and what kind of solutions that do or do not work, showing that handling of moisture in the construction phase is not the only problem. Further, the survey gave feedback on challenges related to specific technical solutions, e.g. crawl spaces, and what kind of information is missing in relation to moisture-safe construction in Greenland. As key-points, focus should be on project design, improved competences, handling of building materials and components at the building site, and explainable guidelines for specific solutions and building types.

2020 ◽  
Vol 12 (4) ◽  
pp. 348-352
Author(s):  
S. Malchev ◽  
S. Savchovska

Abstract. The periods with continuous freezing air temperatures reported during the spring of 2020 (13 incidents) affected a wide range of local and introduced sweet cherry cultivars in the region of Plovdiv. They vary from -0.6°C on March 02 to -4.9°C on March 16-17. The duration of influence of the lowest temperatures is 6 and 12 hours between March 16 and 17. The inspection of fruit buds and flowers was conducted twice (on March 26 and April 08) at different phenological stages after continuous waves of cold weather conditions alternated with high temperatures. During the phenological phase ‘bud burst’ (tight cluster or BBCH 55) some of the flowers in the buds did not develop further making the damage hardly detectable. The most damaged are hybrid El.28-21 (95.00%), ‘Van’ (91.89%) and ‘Bing’ (89.41%) and from the next group ‘Lapins’ (85.98%) and ‘Rosita’ (83.33%). A larger intermediate group form ‘Kossara’ (81.67%), ‘Rozalina’ (76.00%), ‘Sunburst’ (75.00%), ‘Bigarreau Burlat’ (69.11%) and ‘Kuklenska belitza’ (66.67%). Candidate-cultivar El.17-90 ‘Asparuh’ has the lowest frost damage values of 55.00% and El.17-37 ‘Tzvetina’ with damage of 50.60%.


2000 ◽  
Vol 41 (1) ◽  
pp. 163-166 ◽  
Author(s):  
W. Gebert ◽  
P.A. Wilderer

The investigated effects of heating the filling material in trickling filters were carried out at the Ingolstadt wastewater treatment plant, Germany. Two pilot scale trickling filters were set up. Heat exchanger pipings were embedded in the filter media of one of these trickling filters, and the temperature in the trickling filter was raised. The other trickling filter was operated under normal temperature conditions, and was used as a control. The results clearly demonstrate that the performance of trickling filters cannot be constantly improved by heating the biofilm support media. A sustained increase of the metabolic rates did not occur. The decrease of the solubility of oxgen in water and mass transfer limitations caused by an increase of the biofilm thickness are the main reasons for that. Thus, the heating of trickling filters (e.g. by waste heat utilization) in order to increase the capacity of trickling filters under cold weather conditions cannot be recommended.


2021 ◽  
Vol 6 (11) ◽  
pp. 289-304
Author(s):  
Ahmet Cihat ARI

With the increase of the population recently, changes have occurred in the design and construction techniques of the buildings due to the insufficient building stock. With the development of science and technology, new construction techniques have emerged in the construction and design of structures. In the global population increase, high-rise buildings were built to meet the need for shelter and these structures were built with the development of technology. However, high-rise buildings have become the symbol of technological development for countries and cities. Since the 21st century, the construction of high-rise buildings in cities with different designs and new construction techniques has provided the development of architecture and engineering. It is important to design high-rise buildings in accordance with the culture and texture of the city. In addition, high-rise buildings should be built as structures resistant to natural disasters such as earthquakes, fires and floods. For this reason, the design and construction techniques of high-rise buildings have become a research subject in the field of architecture and engineering. The aim of this study is to examine the designs and construction techniques of high-rise buildings. In the first part of the study, the concept of high rise building and its historical development are discussed. In the second part of the study, the designs and construction techniques of high-rise buildings are investigated. In addition, the study was conducted to examine the high structure by giving examples from the world and Turkey. Within the scope of the study, literature researches such as domestic and international articles, books, published theses, web resources were conducted and data were collected. As a result of the examinations made within the scope of the study, it is important to select the building materials in accordance with the characteristics of the building materials in the design and construction techniques of high-rise buildings with the development of technology. Therefore, the architect should know the properties of the materials in the design of high-rise buildings and use them in accordance with the properties of the material in the construction of the buildings. In addition, increasing the height of the building by making aerodynamic designs in high buildings reduces the effect of the wind speed.


2014 ◽  
Vol 133 (3) ◽  
pp. 187-190 ◽  
Author(s):  
Daniel de Oliveira Gomes ◽  
Rafael Rocha Vidal ◽  
Bruno Figueiredo Foeppel ◽  
Danilo Fiorindo Faria ◽  
Minori Saito

CONTEXT AND OBJECTIVE:Testicular torsion is a medical and urological emergency because it can lead to loss of the organ. The theory of seasonal testicular torsion occurrence is based on studies from institutions located in cold and temperate regions. The objective here was to determine whether cold weather is associated with higher incidence of testicular torsion in a tropical country, such as Brazil.DESIGN AND SETTING:Retrospective study, conducted in a tertiary and teaching hospital.METHODS:Patients with acute testicular torsion confirmed by surgery between April 2006 and March 2011 were studied. Information on weather conditions at the time of symptom onset was collected.RESULTS:A total of 64 testicular torsion cases were identified. The months with the highest incidences of testicular torsion were June (16%), July (19%) and August (11%), which had the lowest mean temperatures, of 17.6 °C, 16.4 °C and 18.2 °C, respectively. Eleven percent of cases occurred during spring (October to December), 16% occurred in summer (January to March), 34% occurred in fall (April to June) and 39% occurred in winter (July to September). There was a significant association between the incidence of testicular torsion and the season (fall and winter), P < 0.001.CONCLUSIONS:Testicular torsion follows a seasonal association even in a tropical country, and is more frequent in the colder months of the year, namely fall and winter, when almost three-quarters of the cases occurred. These observations add further evidence that cold weather has an etiologic role in testicular torsion occurrence.


Author(s):  
A. Oudrane ◽  
Benaoumeur Aour ◽  
Zeghmati Belkacem ◽  
Massaud Hamouda

This work focuses on the numerical investigation of different modes of heat exchangebetween the habitat and its environment in an extremely hot climate to optimize thermal comfort.Notably, to optimize habitable comfort, it is essential to model the solar flux and the temperatureabsorbed by the habitat walls. In this context, we have developed an analytical model to predict heatexchange for a habitat in the Adrar region. The heat transfer equations have been established in eachwall of the habitat. These equations were discretized by the finite difference method and solvedusing the Gauss algorithm. The models developed were validated with climatic data measured in theresearch unit ''URER'MS'' in Adrar. The results obtained showed that building materials andextreme weather conditions were the decisive parameters of unwanted overheating.


2021 ◽  
Author(s):  
Dragos Vas ◽  
Steven Peckham ◽  
Carl Schmitt ◽  
Martin Stuefer ◽  
Ross Burgener ◽  
...  

Ice fog events, which occur during the Arctic winter, result in greatly decreased visibility and can lead to an increase of ice on roadways, aircraft, and airfields. The Fairbanks area is known for ice fog conditions, and previous studies have shown these events to be associated with moisture released from local power generation. Despite the identified originating mechanism of ice fog, there remains a need to quantify the environmental conditions controlling its origination, intensity, and spatial extent. This investigation focused on developing innovative methods of identifying and characterizing the environmental conditions that lead to ice fog formation near Fort Wainwright, Alaska. Preliminary data collected from December 2019 to March 2020 suggest that ice fog events occurred with temperatures below −34°C, up to 74% of the time ice fog emanated from the power generation facility, and at least 95% of ice particles during ice fog events were solid droxtals with diameters ranging from 7 to 50 μm. This report documents the need for frequent and detailed observations of the meteorological conditions in combination with photographic and ice particle observations. Datasets from these observations capture the environmental complexity and the impacts from energy generation in extremely cold weather conditions.


2014 ◽  
Vol 1029 ◽  
pp. 118-123
Author(s):  
Rodica Bădărău ◽  
Teodor Miloş ◽  
Ilare Bordeaşu ◽  
Adrian Bej

The paper presents a case study on the original solution of a flange shaft as part of the root area of a 5 kW wind turbine blade. There were analyzed the causes that led to the shaft breakage under wind loadings in extreme weather conditions, and consequently technical solutions have been searched in order to improve the shaft design making it more reliable as mechanical strength at extreme wind loadings. The flange shaft is a welded subassembly that keeps the blades attached to the rotor hub. The first part of the paper consists in an analysis referring the loading status, the materials used for blade manufacturing, the identification of critical areas where the breaking was initiated and also the causes for which the materials assumed and specified in the technical design and manufacturing technology failed under loading at wind gusts of about 30 m/sec. Based on this preliminary analysis, the second part of the paper presents the technical solutions which were considered in reference to the materials and the improved design concept aiming to provide the right mechanical strength necessary to withstand specific wind loadings in extreme weather conditions.


2021 ◽  
Vol 10 ◽  
Author(s):  
Hossein Ahangari ◽  
Haleh Forouhandeh ◽  
Tahereh Ebrahimi ◽  
Vida Ebrahimi ◽  
Soheila Montazersaheb ◽  
...  

Background: Sabalan (Savalan) Lake is a stable crater lake locating at the summit of Sabalan, an inactive stratovolcano and the third highest mountain of Iran. Because of cold weather conditions, the lake is frozen in most months of the year. The biodiversity of microbial flora in this area needs to be explored to find its similarity with the arctic regions’ biodiversity. Objective: The psychrophilic bacterial population of Sabalan (Savalan) Crater Lake was identified. The current research is the first report of aquatic bacterial strains isolation and characterization from Sabalan Lake. Methods: Water sample collections were cultured on four different media, then colonies were isolated by the plating method. The phylogenetic features of the isolates were scrutinized and finally, the phenotypic characteristics were investigated using specific culture methods. Results: The results of morphological tests indicated that most isolates were Gram-negative and rod shape, which were able to grow between ˗4 and +37 ºC.‎ According to the phylogenetic analysis the isolated strains belong to Pseudomonas, Yersinia, Kocuria, and Micrococcus genera and about 60% of the isolates belong to the various species of Pseudomonas as a ‎dominant genus with abounded frequency. ‎In addition, several isolates showed 99% similarity with bacteria, which were previously isolated from Antarctic regions such as Pseudomonas antarctica and Micrococcus antarctica. Conclusion: It can be concluded that the microbial populations of cold areas is the same across the geographical distances. In addition, these bacterial strains could be a primitive source of new enzymes for technological applications such as biosurfactant production.


2014 ◽  
Vol 39 (2) ◽  
pp. 78-83
Author(s):  
Henk Visscher ◽  
Dasa Majcen ◽  
Laure Itard

The energy saving potential of the building stock is large and considered to be the most cost efficient to contribute to the CO2 reduction ambitions. Severe governmental policies steering on reducing the energy use seem essential to stimulate and enforce the improvement of the energy performance of buildings with a focus on reducing the heating and cooling energy demand. In Europe the Energy Performance of Buildings Directive is a driving force for member states to develop and strengthen energy performance regulations for new buildings and energy certificates for the building stock. The goals are to build net zero energy new buildings in 2020 and to reach a neutral energy situation in the whole stock by 2050. More and more research projects deliver insight that the expected impact of stricter regulations for newly built houses is limited and the actual effects of energy savings through housing renovations stay behind the expectations. Theoretical energy use calculated on base of the design standard for new houses and assessment standards for Energy Performance Certificates of existing dwellings differ largely from the measured actual energy use. The paper uses the findings of some Post Occupancy Evaluation research projects. Is the energy saving potential of the housing stock smaller than expected and should we therefore change the policies?


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