scholarly journals Opaque Ventilated Façade (OVF) Thermal Performance Simulation for Office Buildings in Brazil

2020 ◽  
Vol 12 (18) ◽  
pp. 7635
Author(s):  
Camila Gregório-Atem ◽  
Carolina Aparicio-Fernández ◽  
Helena Coch ◽  
José-Luis Vivancos
Keyword(s):  
Mineral Wool ◽  
Climatic Conditions ◽  
Office Buildings ◽  
Aluminium Composite ◽  
Specific Design ◽  
Performance Simulation ◽  
Climate Conditions ◽  
Hot Climate ◽  
Occupant Comfort ◽  
Ventilated Facade

Opaque ventilated façades (OVFs) are increasingly gaining in importance in the design of sustainable buildings, given that they can lessen the building´s environmental impact. Opaque ventilated façades can reduce thermal gains in hot climate zones, improving the thermal comfort indoors, and reducing air conditioning demand. Nevertheless, the thermal behaviour of the opaque ventilated façade depends on the climatic conditions and the building´s specific design. This study analyses the effect of opaque ventilated façades in office buildings using 30 constructive configurations under eight tropical climate conditions. The study considers three options for the external layer of cladding (ceramic, stone, and aluminium composite material) and two configurations for the inner layer (plasterboard with mineral wool and ceramic). Simulations were carried out using the software tools TRanNsient SYstem Simulation program (TRNSYS) and TRNFlow. The model developed considers bioclimatic characteristics, including solar radiation and wind conditions for each climatic zone. The operating temperature was selected from within the range established by occupant comfort regulations. The findings suggest that it is possible to select the best office building opaque ventilated façade configuration for each of the specific climate conditions in Brazil.

scholarly journals Experimental Study of the Effect of Curing Mode on Concreting in Hot Weather

2021 ◽  
Vol 31 (4) ◽  
pp. 243-248
Author(s):  
Nassima Bakir
Keyword(s):  
Experimental Study ◽  
Concrete Surface ◽  
Work Conditions ◽  
Climatic Conditions ◽  
Water Evaporation ◽  
Negative Effects ◽  
Climate Conditions ◽  
Hot Climate ◽  
Hot Weather ◽  
Job Site

Most developing countries have hot climate, ordinary jobsites characterized by reduced of human resources, equipment and infrastructures. The objective of this article is to make an experimental study of the influence of the hot climate such as that of Algeria, on the different properties of concrete in the fresh state, such as excessive water evaporation from the concrete surface, increased demand for water, increased slump loss corresponding to additional water on job-site, higher plastic shrinkage cracking and difficulty in controlling air content. At the hardened state, we could mention a reduction of strength at 28 days, decreased durability resulting from cracking at long-term period. To show the problems linked to concreting under these conditions and to present the appropriate solutions concrete or mortar can withstand the conditions in which it is implemented. Thus, negative effects caused principally by hot weather concreting motivated the choice of the such study. The research experimental work conditions in which the cementitious matrix was kept concerned two different environments, namely hot and dry climate conditions (t = 40°, h = 0%) alike the climate of the region of M'sila., and that of a medium with a hot and humid environment (t = 40°, h = 100%). The output of the investigation demonstrated the crucial role of the cure method in hot regions. The comparison of results for a reference concrete kept in air without any curing measures with two curing types simulating hot weather environment of the region M’sila was undertaken. These obtained outcome results were discussed based on the influence of climatic conditions to conclude procedures for hot weather concreting and suitable cure methods.

scholarly journals Occurrence and Identification of Aspergillus Section Flavi in the Context of the Emergence of Aflatoxins in French Maize

Toxins ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 525 ◽  
Author(s):  
Sylviane Bailly ◽  
Anwar Mahgubi ◽  
Amaranta Carvajal-Campos ◽  
Sophie Lorber ◽  
Olivier Puel ◽  
...  
Keyword(s):  
Global Warming ◽  
Secondary Metabolites ◽  
Climatic Conditions ◽  
Special Focus ◽  
Climate Conditions ◽  
Aspergillus Section Flavi ◽  
Maize Field ◽  
Hot Climate ◽  
Field Samples ◽  
Aspergillus Section

Aflatoxins (AFs) are secondary metabolites produced by Aspergillus section Flavi during their development, particularly in maize. It is widely accepted that AFB1 is a major contaminant in regions where hot climate conditions favor the development of aflatoxigenic species. Global warming could lead to the appearance of AFs in maize produced in Europe. This was the case in 2015, in France, when the exceptionally hot and dry climatic conditions were favorable for AF production. Our survey revealed AF contamination of 6% (n = 114) of maize field samples and of 15% (n = 81) of maize silo samples analyzed. To understand the origin of the contamination, we characterized the mycoflora in contaminated samples and in samples produced in the same geographic and climatic conditions but with no AFs. A special focus was placed on Aspergillus section Flavi. A total of 67 strains of Aspergillus section Flavi were isolated from the samples. As expected, the strains were observed in all AF+ samples and, remarkably, also in almost 40% of AF− samples, demonstrating the presence of these potent toxin producers in fields in France. A. flavus was the most frequent species of the section Flavi (69% of the strains). But surprisingly, A. parasiticus was also a frequent contaminant (28% of the strains), mostly isolated from AF+ samples. This finding is in agreement with the presence of AFG in most of those samples.

Ecological specificities of the interaction between animal breeding and climate changes, caused by greenhouse gas emissions

2017 ◽  
Vol 4 (3) ◽  
pp. 62-72
Author(s):  
O. Zhukorsky ◽  
O. Nykyforuk ◽  
N. Boltyk
Keyword(s):  
Greenhouse Gases ◽  
Greenhouse Gas Emissions ◽  
Greenhouse Gas ◽  
Climatic Conditions ◽  
Animal Breeding ◽  
Gas Emissions ◽  
Climate Conditions ◽  
Emissions Inventory ◽  
Theoretical Substantiation ◽  
Global Problems

Aim. Proper development of animal breeding in the conditions of current global problems and the decrease of anthropogenic burden on environment due to greenhouse gas emissions, caused by animal breeding activity, require the study of interaction processes between animal breeding and external climatic conditions. Methods. The theoretical substantiation of the problem was performed based on scientifi c literature, statistical informa- tion of the UN Food and Agriculture Organization and the data of the National greenhouse gas emissions inventory in Ukraine. Theoretically possible emissions of greenhouse gases into atmosphere due to animal breeding in Ukraine and specifi c farms are calculated by the international methods using the statistical infor- mation about animal breeding in Ukraine and the economic-technological information of the activity of the investigated farms. Results. The interaction between the animal breeding production and weather-and-climate conditions of environment was analyzed. Possible vectors of activity for the industry, which promote global warming and negative processes, related to it, were determined. The main factors, affecting the formation of greenhouse gases from the activity of enterprises, aimed at animal breeding production, were characterized. Literature data, statistical data and calculations were used to analyze the role of animal breeding in the green- house gas emissions in global and national framework as well as at the level of specifi c farms with the consid- eration of individual specifi cities of these farms. Conclusions. Current global problems require clear balance between constant development of sustainable animal breeding and the decrease of the carbon footprint due to the activity of animal breeding.

scholarly journals Relationship between Relative Maturity and Grain Yield of Maize (Zea mays L.) Hybrids in Northwest New Mexico for the 2003–2019 Period

Agriculture ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 290
Author(s):  
Koffi Djaman ◽  
Curtis Owen ◽  
Margaret M. West ◽  
Samuel Allen ◽  
Komlan Koudahe ◽  
...  
Keyword(s):  
New Mexico ◽  
Grain Yield ◽  
Sprinkler Irrigation ◽  
Growing Season ◽  
Climatic Conditions ◽  
Agricultural Science ◽  
Production Optimization ◽  
Science Center ◽  
Early Season ◽  
Climate Conditions

The highly variable weather under changing climate conditions affects the establishment and the cutoff of crop growing season and exposes crops to failure if producers choose non-adapted relative maturity that matches the characteristics of the crop growing season. This study aimed to determine the relationship between maize hybrid relative maturity and the grain yield and determine the relative maturity range that will sustain maize production in northwest New Mexico (NM). Different relative maturity maize hybrids were grown at the Agricultural Science Center at Farmington ((Latitude 36.69° North, Longitude 108.31° West, elevation 1720 m) from 2003 to 2019 under sprinkler irrigation. A total of 343 hybrids were grouped as early and full season hybrids according to their relative maturity that ranged from 93 to 119 and 64 hybrids with unknown relative maturity. The crops were grown under optimal management condition with no stress of any kind. The results showed non-significant increase in grain yield in early season hybrids and non-significant decrease in grain yield with relative maturity in full season hybrids. The relative maturity range of 100–110 obtained reasonable high grain yields and could be considered under the northwestern New Mexico climatic conditions. However, more research should target the evaluation of different planting date coupled with plant population density to determine the planting window for the early season and full season hybrids for the production optimization and sustainability.

Human occupation strategies and related environmental-climate during the middle and late Holocene in central Pampas of Argentina

The Holocene ◽  
2018 ◽  
Vol 29 (2) ◽  
pp. 244-261 ◽  
Author(s):  
Pablo G Messineo ◽  
Marcela S Tonello ◽  
Silvina Stutz ◽  
Alfonsina Tripaldi ◽  
Nahuel Scheifler ◽  
...  
Keyword(s):  
Late Holocene ◽  
Specific Activity ◽  
Climatic Conditions ◽  
Hard Material ◽  
Human Occupation ◽  
Climate Conditions ◽  
Lithic Assemblage ◽  
Depositional Rate ◽  
Archeological Site ◽  
Middle And Late Holocene

The main objective of this work is to generate and integrate interpretations of human occupation strategies and inferences of the environmental-climatic conditions in the central Pampas during the middle and late Holocene. We present a novel archeological–geological–paleoecological analysis in the area of the Cabeza de Buey lake, placed in an aeolian landscape. During the middle Holocene, two events of human occupations were recognized at Laguna Cabeza de Buey 2 archeological site. Both events present a small amount of lithic materials, a low diversity of tools and activities developed with them (principally hard material), and the hunting and primary processing of artiodactyls. These evidences suggest a locus of specific activity associated with an ephemeral human settlement under climate conditions drier than present and the presence of small, brackish, and shallow water bodies. For the late late Holocene, the hunter-gatherer occupation has a higher depositional rate of lithic assemblage, stones with diverse origins, presence of pottery fragments, a great lithic tool diversity, knapping techniques, and activities developed with these tools (processing wood, bone, hide, non-woody plant, and soft material). These evidences reveal an occupation with a higher degree of recurrence represented by a locus of multiple activities associated with a more stable landscape, such as an environment of dunes fixed by grass vegetation, and the establishment of a permanent water body. The different environmental characteristics for the middle and late Holocene in this area promoted that human groups develop two different patterns of mobility, settlement and use of space.

scholarly journals Potential of Sunflower-Legume Intercropping: A Way Forward in Sustainable Production of Sunflower in Temperate Climatic Conditions

2021 ◽  
Author(s):  
Brankica Babec ◽  
Srđan Šeremešić ◽  
Nada Hladni ◽  
Nemanja Ćuk ◽  
Dušan Stanisavljević ◽  
...  
Keyword(s):  
Red Clover ◽  
Climatic Conditions ◽  
Sustainable Production ◽  
Oilseed Crop ◽  
Common Vetch ◽  
General Belief ◽  
Climate Conditions ◽  
Sole Crop ◽  
Sole Cropping ◽  
Almost All

Changing climate conditions coupled with the transformations of cultivation practices and land use in sole crop-based sunflower production may significantly decline yield stability of this oilseed crop. Given that sunflower takes the third place in the world oilseed market, with 45 million tons per year, and in the fourth place in vegetable oil production, it is necessary to adapt production technologies toward sustainable agriculture. Considering that, the goal of the research was to analyze and beneficial sustainable production technology of sunflower in intercropping systems. A four-year trial was conducted in Serbia’s agroecological rain-fed conditions (45°34’23.2"N 19°86’18.9"E) using a split-plot design. Two oil types and one confectionary sunflower hybrid were intercropped with common vetch, red clover and alfalfa. Analyses showed that intercropping of sunflower with common vetch resulted in the decrease in almost all sunflower trait values. Also, sunflower × alfalfa intercropping provided to be the most appropriate. The yield of NS Gricko and Rimi PR were statistically on the same level with sole cropping, while alfalfa biomass had better results when intercropped with NS Gricko as compared to sole cropping. Concerning the general belief that yields are more stable in intercropping than in sole crop, further research in this respect is needed, in addition to the research of time and method of sowing.

scholarly journals Thermal extras of vegetation walls in Belgrade climatic conditions

2018 ◽  
Vol 22 (Suppl. 3) ◽  
pp. 945-955 ◽  
Author(s):  
Budimir Sudimac ◽  
Aleksandar Andjelkovic ◽  
Sanja Dubljevic
Keyword(s):  
Energy Balance ◽  
Thermal Characteristics ◽  
Climatic Conditions ◽  
Office Buildings ◽  
Sustainable Technologies ◽  
Summer Time ◽  
Outer Environment

The goal of this research is to analyse the possibility of using vegetation walls in order to improve the thermal characteristics of office buildings in Belgrade?s climatic conditions. The study analyses the possibility of integrating vegetation modules into the fa?ades of office buildings. The paper shows the potential of vegetation technologies in the realisation of fa?ade coverings of architectural buildings with a goal to reduce heat gained during summer time. The use of vegetation walls in architecture has opened up new planning possibilities and created planning conditions for reducing the energy necessary for cooling office buildings. Considering that interaction between the outer environment and inner solving the dependency between comfort, outer look and building?s energy balance. This paper is presenting the possibility of using sustainable technologies for solving the problem of overheating in Belgrade?s climatic conditions. The research considers the possibilities of using vertically greening systems in planning fa?ade coverings, with an analysis of their thermal characteristics for climatic conditions in Belgrade.

scholarly journals The Impact of Aspect Ratio on External Heat Gain of Multi-storey Office Buildings in Jakarta

2018 ◽  
Vol 16 (1) ◽  
pp. 24-31
Author(s):  
Wasiska Iyati ◽  
◽  
Eryani Nurma Yulita ◽  
Jusuf Thojib ◽  
Heru Sufianto ◽  
...  
Keyword(s):  
Aspect Ratio ◽  
Building Design ◽  
Climatic Conditions ◽  
Building Envelope ◽  
External Heat ◽  
Office Buildings ◽  
Office Building ◽  
Cooling Load ◽  
Heat Gain ◽  
The Impact

The narrow land in big cities such as Jakarta, increases the amount of high rise building, especially multi-storey office building. Office building consumes much energy to provide air conditioning to meet the thermal comfort inside the building. On the other hand, the building shape, building envelope, and building orientation to the sun's position are the main factors in building design aspects that affect the amount of cooling load. This study aims to investigate the impact of the aspect ratio or the ratio of the longer dimension of an oblong plan to the shorter, on external heat gain of multi-storey office building. Variables examined include the transparent and solid area of building envelope, the total area of the surface of the building envelope in any orientation, and the volume of the building, as well as the influence of those proportion on the external heat gain. This study uses mathematical calculations to predict the cooling load of the building, particularly external heat gain through the walls, roof and glass, as well as comparative analysis of models studied. The study also aims to generate the design criteria of building form and proportion of multi-storey office buildings envelope with lower external heat gain. In Jakarta climatic conditions, the result on rectangular building plan with aspect ratio of 1 to 4 shows that the external heat gain did not differ significantly, and the smallest heat gain is found on the aspect ratio of 1.8. Results also showed that the greater aspect ratio, the greater reduction of external heat gain obtained by changing the orientation of the longest side facing east-west into the north-south, about 2.79% up to 42.14% on the aspect ratio of 1.1 to 4. In addition, it is known that in same building volume, changing the number of floors from 10 to 50 can improve the external heat gain almost twice.

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