适用于伊朗的纸和木材业的一种白杨木材供应模式(英文)

研究目的是为伊朗的纸和木材业寻找一种利用白杨木材作为原材料的供应模式。由于森林的破坏和缺乏适合的植被,利用速生木材树种满足纸和木材业的需要是非常重要的。通过数层次分析(AHP)方法,区分优先次序如:效益。机会,价值和风险。为了评价系统的控制标准,利用网络分析法(ANP)优化和得出一种控制等级制度。4个主要控制标准被优化,其中每个标准控制一个由ANP评价的网络模式。最终的系统分析结果表明:在三个供应模式中(工厂供货,国外供货和最大化供货),森林产品工厂提供国内白杨木材是最好的选者。表4参15。

Estimating the costs of one hectare of poplar planting and supplying wood required for producing various types of paper in Iran

In Iran, due to abundant restrictions on harvesting wood from northern forests by implementing the preservation project and also lack of possibility for sufficient wood production, development of the area of planting poplar is quite inevitable. Poplar wood properties have special importance to produce many wood production, particularly pulp and paper. Paper factories are the major consumers of poplar wood at the global level and this is because of unique morphological, physical, mechanical and technological properties of poplar wood. Therefore, regarding the importance of using this species in making various printing and writing paper, packaging or carton, cardboard and newsprint, in this study, costs of poplar production in one hectare including planting and harvesting were examined and determined. Then, based on conversion coefficients of FAO, required round wood, productivity and the cost of poplar wood were calculated for the producing various kinds of paper. The results indicate that carton and cardboard paper or packaging allocate the lowest cost and highest return, while printing and writing paper had highest cost and lowest return in terms of poplar wood supply needed for paper production.

A decision making model for investment and development of construction panels

A study was conducted to select the best alternative for the development of construction panels as well as investment in its manufacturing in Iran.Three alternatives are considered,cement-bonded wood composite product,substituted products（such as concrete panel） sandwich panel and a mixture of them.We apply the analytic network process（ANP） to achieve this goal.A hierarchy is designed to prioritize benefits,opportunities,costs and risks（BOCR） by using the Analytic Hierarchy Process（AHP） ratings approach.To evaluate the ＂control criteria＂ of the system,a control hierarchy is also created and prioritized by applying the Analytic Network Process（ANP）.A total of four major control criteria in the system are prioritized where each one controls a decision network evaluated using ANP.The final synthesis of the system shows cement-bonded wood composite product is the best choice among three potential alternatives for the investment and development.

A multiple criteria analysis of factors affecting markets of engineered wood products with respect to customer preferences: a case study of particleboard and MDF

Of considerable importance and a principal goal in business is the creation of customer satisfaction. Evalu- ation of end user preferences for producers of particleboard and medium density fiberboard （MDF） requires indices for the assessment of markets and modification of product quality. However, only sporadic research has been carried out in this field. Therefore, the goal of this survey was to identify indices with respect to the points of view of： 1） consumers in order to select particleboard and MDF, 2） suppliers in order to consider production strategies, improve product quality, improve competitive ability of domestic producers in the market and help industry to be more customer oriented. This survey consisted of two stages. In the first stage, factors affecting customer preferences in the selection of particleboard and MDF were determined using a Delphi method, with the help of experts and a group of principal users of these prod- ucts. Then these factors were categorized in three groups： qualitative, technical and technological and marketing factors. Furthermore, questionnaires were prepared and distributed among consumers and responses evaluated and weighted by using an analytic hierarchy process （AHP） using expert choice software. Our results show that at both stages, the consistency ratio was less than 0.1, indicating that all results and judgments were stable and acceptable. The results obtained from questionnaires about particleboard rank the priorities for factors in the selection by consumers as follows： nail and screw holding ability, homogeneity in structure, edge strength of panel, durability and bending strength. The most important factors for MDF were machinability of panels, homogeneity in structure, nail and screw holding ability, edge strength of panel, durability and bending strength.

Quantitative study of poplar plantations in three Iranian provinces

Fast growing poplar species enjoy a highly favored position in Iran’s forest product industries. However, information on poplar plantations, such as areas, growing stock and harvest volumes, are largely obtained by non scientific means and poorly executed methods. A few studies have been conducted to obtain data on the capacity of poplar plantations, their extent, existing growing stock, distribution and species choice in three provinces, i.e., Western Azerbaijan, Kurdistan and Hamedan, with relatively well developed management systems. We opted for a cluster method, a standard sampling method for conducting similar investigations, consisting of two phases. In the first phase we collected library information and conducted half-open interviews with villagers. In the second phase field measurements in the villages of these three provinces were carried out. Information from field measurements on growing stock, cultivated areas, dominant species were used to estimate volumes by way of volume and weight tables. Results obtained from the present study indicate that the average annual volume of timber harvested in the three provinces was 697,723 m3, with an average sampling error of 22.7 per cent. This annual volume of poplar timber harvested from the three provinces was estimated to amount to about 25 per cent of overall harvest; at that rate, the overall annual utilization potential of poplar plantations will be 10 million m3, which constitutes a reliable resource of raw timber for use in wood and paper industries.

Changes in biochemical properties of tomato(cv.240)affected by combination of blue/red optical spectra and Calfomyth spray(Ca and P)

The levels of antioxidant activity and vitamins can change with varying ratios of different wavelengths.This study was conducted as a pot experiment under soilless culture conditions in order to investigate the interactive effects of light supplementation and nutrition(calfomyth solution)on some qualitative traits of tomato fruit.The research was carried out as a split-plot experiment based on a completely randomized design with three light treatments including without supplementary light(control),60% red light+40% blue light and 90%red light+10% blue light.There were two nutritional treatments including no spraying with calfomyth as commercial fertilizer and foliar application with a concentration of 2 mg/L in three replicates.According to the results,the amounts of vitamin C(16.1 mg/g FW fruit),soluble solids(12.33 mg/g FW fruit),and lycopene(2.95 mg/g FW fruit)were all uppermost by the effect of a higher percentage of red light treatment.Higher percentage of the blue light resulted in the highest leaf chlorophyll content(38.4 mg/g FW leaf),but supplementary light treatments had no significant effects on the titratable acidity.Nutrition(calfomyth foliar application)showed positive impacts on all treatment traits compared to control.Beta-carotene content was affected by none of the treatments with no significant differences.According to this research,it can be expected that the use of complementary light treatments and calfomyth foliar spray may have positive effects on most of the qualitative traits in tomato fruit(cv.240).