Amir Mollahassani; Amir Hooman Hemmasi; Habibollah Khademi Eslam; Amir Lashgari; behzad baziyar
Abstract
The aim of this study is to evaluate the dynamic and static of elastic properties of Fir wood joints. For this purpose conventional joints in woos industry including dovetail, tongue and groove beech wood (Abies alba.) joints with polyvinyl acetate (PVA) and cyanoacrylate (CA) adhesives were used. Dimensions ...
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The aim of this study is to evaluate the dynamic and static of elastic properties of Fir wood joints. For this purpose conventional joints in woos industry including dovetail, tongue and groove beech wood (Abies alba.) joints with polyvinyl acetate (PVA) and cyanoacrylate (CA) adhesives were used. Dimensions of research samples were determined 24×50×360 (mm) according to international standard (ISO No.3129), and the results indicate that the effects of joint type, adhesive type, joint size, and also retrospective joint size became meaningful at 5% level in dynamic and static tests. As the length of groove and height of dovetail and length of dowel increased in the joints, dynamic and static elasticity modules increased, and in terms of changes in elasticity modules of the research. Elasticity module for dovetail joint, as a result of the shape, having a homogenous joint texture, and also lack of extended adhesive line in the joint, is closer to un jointed samples (control group). Also cyanoacrylate adhesive improved elasticity features of samples compared to polyvinyl acetate adhesive as a result of higher tension resistance and faster coagulation. The results of the Student's t-test indicate that there exists a not significant difference between the mean of dynamic and the mean of static modulus of elasticity, not significance at 5% level and The Pearson correlation test indicate that the dynamic and static modulus of elasticity of the samples are significant at 5% level and are of positive correlation(+.0958) .With regard to the correlation of the results of dynamic and static tests, methods for non-destructive dynamic investigation may be regarded as appropriate alternatives to destructive static tests, in order to assess and classify woods.
Management and Economics wood
Hamed Ahmadi; Ajang Tajdini; Amir Lashgari
Abstract
In this research, the impact of various products design was investigated in end-customer’s satisfaction. . For this purpose, the variables are: products ‘external characteristic variables, quality, price, distributing system, after sales services, perceived value and sex moderator variable. ...
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In this research, the impact of various products design was investigated in end-customer’s satisfaction. . For this purpose, the variables are: products ‘external characteristic variables, quality, price, distributing system, after sales services, perceived value and sex moderator variable. The statistical population of this research includes all the consumers of household wooden steel furniture in Tehran city. In order to evaluate and examine the conceptual model, structural equation method and AMOS software are used. The results showed that the model has been fitted in the first-grade and second-grade measurement models and also on structural model. In measurement model, the measurement indices have created some meaningful factor loadings. This issue shows that model has been determined from theoretical literature and the criteria of this measurement have been recognized correctly. This caused a high validity of the measurements ‘tools. The variables of external characteristics, quality, price, after -sales services and perceived value are all effective at 99 percent of the confidence level on the consumer of household wooden furniture. But, the effect of distributing system variable on customer satisfaction did not accept. Also according to the obtained results, it is clear that sex variable can just adapt the relationship between external characteristics and customer satisfaction in the level of 90 percent significance.
Amir Bagheri; Vahid reza Safdari; Amir Lashgari; Azhang Tajadini
Abstract
Ephedra shrubs are among native species of Iran and Turan habitat but their anatomical and physical characteristics have not been studied yet. In this study,physical characteristics of wood logs from three ephedra species including Mianeh Ephedra (Ephedra intermedia ),Goats Beard Ephedra (Ephedra ...
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Ephedra shrubs are among native species of Iran and Turan habitat but their anatomical and physical characteristics have not been studied yet. In this study,physical characteristics of wood logs from three ephedra species including Mianeh Ephedra (Ephedra intermedia ),Goats Beard Ephedra (Ephedra major) and Deserts Ephedra or Central Asian Ephedra (Ephedra strobilaceae Bge.) from desert areas of Yazd province were studied. Results shows that Iranian ephedra species similar to the others species show three key anatomical structures: Vessles, Theracheids and, Fibers. The presence of big pits simillar to tracheid pits in some vessel elements support the idea that they are a bridge group linking angiosperms and gymnosperms. Important anatomical features of Iranian ephedras include occurrence of clear and dendroied bodies, elongated and very hetrogenous wooden rayes and latticed vascular valves. Anatomical differences between the three ephedra species provide the key to identify them. There was not any significant difference between average physical characteristics (wet and dry density, shirinkage and swelling).Whereas, average shirinkage and swelling in radial direction was significantly higher than those in tangentiels direction.
