arches and vaults are of the most important parts of traditional buildings of iranian architecture. in the traditional architecture of iran, before oil was discovered, fuel (such as wood) was one of the high-ranking issues. therefore, iranian traditional architects did their best to reduce the use of wood. there was however, a revival of the use of brick in construction. qomi-poosh technology i...

the mean fiber length of three beech trees (fagus orientalis l.) at the lower and higher points (1% and 75% tree height) of the stem at an intermediate altitude (500-1000m) in the caspian forests in sari region were 1.36 and 1.22mm respectively, close to the values in three trees at high altitude (1000-1500m), that were found to be 1.39 and 1.36 mm. the mean fiber lengths of the whole stem, usi...

wood vinegar is the aqueous phase of the liquid produced during the slow pyrolysis of wood.it has the potential to be used as a pesticide against various weeds, insects and molluscs. due to divergentfeedstocks, pyrolysis processes and storing conditions, the chemical composition of wood vinegar variesbetween producers and time. the aim of our current study was to use the copse snail arianta arb...

Wood is a porous three dimensional, hydroscopic, viscoelastic, anisotropic bio-polymer composite composed of an interconnecting matrix of cellulose, hemicelluloses and lignin with minor amounts of inorganic elements and organic extractives. Some, but not all, of the cell wall polymer hydroxyl groups are accessible to moisture and these accessible hydroxyls form hydrogen bonds with water. As the...

Wood Identification has never been more important to serve the purpose of global forest species protection and timber regulation. Macroscopic level wood identification practiced by wood anatomists can identify wood up to genus level. This is sufficient to serve as a frontline identification to fight against illegal wood logging and timber trade for law enforcement authority. However, frontline ...

This paper describes the analysis of raw wood flows in Slovakia. Material flow analysis was used to reveal and quantify relations between the resources and the primary uses of wood. In particular, two approaches to wood flow modelling were utilised wood balance and wood resource balance. Wood balance was introduced to illustrate a global view of the resources and primary uses of roundwood in Sl...

In order to develop tutoring systems that strike a better balance between system control and student control, or systems that provide guidance and feedback in order to help students learn help-seeking skills, we need a better understanding of (actual and ideal) help seeking. In this paper, we take modest steps toward this goal: First, we continue to assess students help-seeking behaviour in the...

This paper concerns the problem of wood cellular structure image registration. Given the large variability of wood geometry and the important changes in the cellular organization due to moisture sorption, an affine-based image registration technique is not exhaustive to describe the overall hygro-mechanical behaviour of wood at micrometre scales. Additionally, free tools currently available for...

The basic hypothesis for the assessment of fire resistance of wood structures is that for temperatures above 300 oC, wood is no longer able to sustain any load. Consequently, the determination of the location of the 300 oC isotherm, the charring depth, is decisive for the result of fire resistance calculation methods. Charring rate of wood is dependent of numerous factors, such as wood species ...

2010 KTH accounts for one-third of Sweden's technical research and engineering education capacity at university level. Education and research cover a broad spectrum – from natural sciences to all the branches of engineering. Part of this work was performed a Innventia AB. Innventia AB is a world leader in research and development relating to pulp, paper, graphic media, packaging and biorefining...