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Aims: The construction sector accounts for a large portion of the world's energy consumption; in Iran, it’s more than 40% of energy consumption. Office buildings have a relatively unfavorable energy consumption pattern due to impersonal ownership and lack of supervision and needs improvement. The aim of this research is to improve the energy performance of these buildings by using a dynamic double skin façade.

Materials and Methods: In this research, first the dominant pattern of office buildings in Mashhad has been studied. Since the design is done in Mashhad, which is one of the religious centers of the country, and to create this feeling in users, the pattern used in its second skin is inspired by Islamic patterns of tiles and decorations of the holy shrine of Imam Reza (AS). After analyzing the energy performance of 5 selected patterns with Ladybug and Honeybee plugins, the most optimal pattern is used.

Findings: Daylight is one of the most influential parameters in the design of energy efficient buildings. To make the most of this parameter, it is necessary to create facades with maximum transparency. But these facades face challenges such as overheating. Therefore, it’s important to control the amount of daylight entering.

Conclusion: In this research based on highperformance architecture theory, an optimal solution to improve the energy performance of a 5-storey office building in Mashhad by using a dynamic double skin façade with the ability to control the daylight entrance is presented; which results in a reduction in building’s energy consumption by approximately 130,000 kWh per year.
 

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It is well known that sugar beet is sensitive to salinity stress at the germination stage. Three separate experiments were conducted to study the effects of salinity on seed germination, plant establishment, and yield of sugar beet genotypes for screening purposes. These included: (a) A laboratory study using four water salinity levels (with EC values < 0.1 as the control, 16, 20, and 24 dS m^-1) with 20 sugar beet genotypes, which were evaluated in a factorial completely randomized design with four replications, and seedling characteristics were measured; (b) A greenhouse experiment where the same statistical design as the lab study was used for seed germination and establishment of 19 sugar beet materials, with irrigation water EC= 3 and 16 dS m^-1; and (c) A field experiment that was carried out to study the response of nine selected genotypes to irrigation waters with EC= 4 and EC= 16 dS m^-1, using a split plot design with three replications. Interaction effects of salinity and genotypes were statistically significant (α= 0.01) for percentage of germination, abnormal seedling, and root and hypocotyls lengths. Indeed, sugar beet germination decreased to 35% and dead seedlings increased to 80 % under salinity stress (EC= 16 dS m^-1) in the greenhouse. Genotypes were ranked from tolerant to susceptible. The results of field experiment were consistent with that obtained in the greenhouse. It can be concluded that salt stress decreased seed germination and, later on, crop establishment by increasing dead seedlings; consequently, sugar beet yield decreased. It seems that establishment is more susceptible to salinity than germination. Root length and abnormal seedling are good indexes for screening sugar beet genotypes for salinity tolerance at the primary growth stages.