abolghasem khazaian

The practical and functional necessity of this research is to investigate the impact of technology on each sub-system of human resources management and to determine the deficiencies and improvable points in the human resources management system in wood industry factories, to make changes in it with a comprehensive vision in case of changing the core technology of wood industry factories is in line with Iran's 20-year vision document in order to prevent the failure of uninformed factories and help the country's policy makers and technology planners to adopt complementary policies and acted comprehensively about technology and its changes. The sample size includes 12 experts, managers of wood industry factories, and elites of the scientific community and university specialists who have executive records at the decision-making levels, and were selected by purposive sampling method and considering the saturation law, and by using the ground theory technique, The research was analyzed by coding method in three open, central and selective stages. The results of the research show that based on the conceptual and secondary codes, the components: 1- Technology features 2- Technology speed 3- Flexibility of technology 4- Responsiveness of technology to market needs were extracted. These identified components provide the possibility of creating a technology-based work environment and its interaction with human resource management in wood-based panels industries. Therefore, paying attention to these four components for the optimal management of human resources and planning for how to face causal conditions (economic, environmental, and social factors); Background conditions (attracting and maintaining human resources; training and skills of employees; planning to improve the health and safety of employees) and Planning to face the effects of intervening conditions such as the government, society, customers, suppliers, investors and employees was necessary and increases the productivity and profitability of the factories of Iran's wood-based panels industries.

The use of wood in outdoor applications causes problems such as dimensional change, weathering and biological degradation. In this study, poplar wood was modified by three types of amino resins (melamine, melamine-urea and urea formaldehyde resins) and nano Zinc oxide (0, 0.5 wt%). Then, the physical properties and weathering resistance of modified wood after six months natural weathering were measured. The results showed that the treatment of wood with amino resins reduced water absorption and improved dimensional stability of samples in which melamine formaldehyde resin had the best performance. Moreover, the addition of nano zinc oxide to the amino resins enhanced their performance in improving dimensional stability of samples. The results of the colorimetry and microscopic images indicate that the treating by melamine formaldehyde reduced the color changes and surface morphology of the samples, although the use of nano zinc oxide did not have a positive effect in this regard.

For chipping primary substance there is different kind of chippers machine. Lot of factors play important role in chips producing which affected whole process. The aim of this research was evaluation of effective parameters on chips quality and energy consumption in knife ring flaker which was done in university of Rosenheim (Germany). In this research used 2 species like Populus termula and Quercus robur. First, round wood with band saw converted to trunk. Follow this chip based on experimental design table feed to knife ring flaker. For precise energy consumption evaluation in any test condition, equal volume of chips in the same time converted to wood particle. Also, knife ring flaker variable parameters was stable in all of the tests. In any test energy consumption during process evaluated with Multi-channel precision power meter device. Then particles based on EN 151491 sieved. The data showed that, with change species from Poplur to Oak energy consumption increase. In addition, increase in moisture from 12% to 30% leads to increase in energy consumption in knife ring flaker, which this difference in energy consumption can be from differences of wood texture in 2 species, while Poplur is diffuse porous to semi-ring porous, Oak is ring porous. Interaction plot of moisture and species showed that in both level of moisture content Oak consume more energy. Also, result reveal that 30% moisture content compared to 12% and Oak in comparison with Poplur produce particles with higher quality.

The purpose of this study was to measure the amount of quality decrease the Hornbeam (Carpinus betulus) wood after three period four months (12 months) of storage in the forest and compare it with the beginning of the period and identify the destroyer fungi that appeared. This research was carried out in Shastkolah in Gorgan. 15 Billets with 30 cm diameter class and length of 220 cm were cut from a Hornbeam tree and all were healthy and stored inside the forest under the same conditions and in contact with soil. The billets were cut at 50 cm intervals at each stage for physical and mechanical experiments were measured based on conventional methods and related standards. the white decay fungi Sterium hirsutum (Willd.),Trametes gibbosa Fr.,Trichaptum biformis Fr. identified on the billets. According to the results, with increasing storage time in the forest, all physical and mechanical properties, except water absorption, decreased. The maximum and minimum changes in physical properties were related to the percentage of water absorption and basic density respectively, also the maximum and minimum changes in mechanical properties related to impact resistance and modulus of elasticity respectively

In this research, nanocellulose fibers were used as adhesive filler in the manufacture of plywood from wych elm (Ulmus globra). Then, the drop-weight impact of the plywood samples was investigated. For this purpose, the nanocellulose fibers were added to dry weight of urea formaldehyde adhesive at four levels of 0, 0.5, 1 and 1.5%. The "4-ply" plywoods were made with these adhesives that the layers in top and bottom were parallel and had two core layers perpendicular with top. In order to investigate the impact properties, plywood samples were tested in the drop-weight impact device. The maximum force on the samples, the displacement in maximum force, the energy consumed in the maximum force and the total absorbed energy were evaluated. The results showed that the sample containing 0.5% of the nanocellulose fibers had the best impact property and with increasing nanocellulose fibers, the impact properties were significantly reduced. Also, the impact resistances in the most of samples with nanocellulose fibers were better than the without nanocellulose (control) samples.

Since human creation up to now، wood has been discussed as an important organic material، therefore its maintain and optimum usage is a considerable problem. From one hand، with due attention to condition of forest in Iran، using fast growing specie Paulownia provides new way in wood industries. But from other hand، this specie with low density has low strength. One of the suggested ways to increase density of this wood is its impregnation by resin and to compress it. In this research it is tried to increase the penetrability and impregnation of Paulownia by using urea formaldehyde resin at first pretreatment and then compression should be done. In order to perform this process، two variables pretreatment and compression percent were defined that each of them had two levels. The pretreatment was performed by NaCl and NaOH and 40، 50% compression. Totally، 72 samples were prepared and after producing the compressed wood، the absorption percent and mechanical properties were evaluated which included compression parallel to grain، modulus of rupture، modulus of elasticity in bending and impact strength. The results showed that the provided mechanical properties and pretreatments samples with NaCl had most values of these properties in 40 and 50% compression levels.

In this research، suitable treatment was studied for increasing resin retention in Paulownia wood. Retention amount of Paulownia with urea formaldehyde resin was studied after treatment by 3 type''s solutions NaOH، NaCl and Urea with 1% and 2% concentrations in 20 and 40 0C during 4 and 8H. By 3 repeats for each treatment، totally 72 specimens with dimension 5×5×15 cm3 were provided. After performing pre-treatment، impregnation was done by urea formaldehyde resin and its polymerization. The results showed the precent of resin retention of the treatment specimens to control was increased and NaCl solution with 2% concentration in 20 0C and during 8H have been had the most effect on resin retention rate. Generally، pre-treatment causes to improve resin retention in Paulownia

In this research، effects of different factors in the CNC machine through- Hole boring of MDF and particleboard were investigated. Variables in boring were selected bit diameter in 3 levels 5،10 and 15 mm، feed speed in 2 levels 0. 3 m/min and 0. 6 m/min and rotary speed of machine axis in 3 levels 300،1500 and 3000 rmp. The goal of this study was to measure effects of mentioned factors on edge- quality of through- holes made in particle- board and MDF. Results have shown that with all bit diameters used، increasing rotary speed of bit improves smoothness of holes in both sides and boring dusts turned to finer sizes. Increasing feed speed did show positive effect on edge surface quality and lowered burr formation.

Shortages of raw wood materials and increasing demand for this raw material، has created challenges for wood working industries. These situation makes wood industries to use wood of fast growing species، such as Paulownia. Expanding plantations of paulownia is a feasible solution، but this species owns a low specific gravity and mechanical properties as well. In this research effects of compreg– impregnated (by phenol for maldehyde resin) treatment on improving mechanical properties of paulownia was studied. Test materials were compressed in tangential and radial directions by 3، 30، 40 and 50 percent at 170 ˚c temperature for 12 minute. Specimens were cut from treated test materials and tested according to Iso-3133 & 3787. Result have shown that resin treatment improves all mechanical properties except toughness. Control specomens had higher toughness as compared with treated ones. MOE and MOR did increase، and turned to be highest specomens compressed 50 % in redial direction.

The aim of this study was to investigate the effective factors on surface quality of paulownia wood during machining by advanced computer numerical controled (CNC) machine. For this aim paulownia logs were provided and were converted to proper sizes (2. 5 x 10 x 15 cm) and then air dried. The Variable of this study were cutting speed (8. 37 and 15. 07 m/s)، feeding rate (6 and 12 m/min)، cutting depth (1and 5 mm)، cutting method (down and up-milling) and cutting pattern (tangential and radial). Roughness of cut specimens edge were evaluated by profilometer method according to ISO 13565 standard. For evaluation of surface quality، average roughness (Ra)، maximum roughness (R max)، valley roughness (Rv) and peak roughness (Rp) were used. Degrees of effectiveness of the parameters were evaluated by fractional factorial design as completely random design at confidence level of 95%. The result showed that cutting speed، cutting method and feed rate are influencive factors on surface quality of machined specimens and their effects were significant. With increasing cutting speed and decreasing feeding rate the roughness decreased and surface quality improved. In up-milling cutting method، degree of roughness was higher and consequently surface quality was inferior. It is to be noted that cutting method in comparison to other factors had the high influence on surface quality. The rest variables did now have independent influence on surface quality at 95% Confidence level. This study for achieving the optimum surface quality recommends that cutting speed of 15. 07 m/s، feeding rate of 6 m/min، cutting method of down-milling and cutting depth of 1 mm for tangential cross section.