Search results for: yield stress

Authors: Siong W. Lee, Kang H. Tan, En H. Yang

Abstract:

This paper presents the results of an experimental study undertaken to evaluate the local bond stress-slip response of short embedment of reinforcing bars in normal concrete (NC) and high performance fiber reinforced cement composites (HPFRCC) blocks. Long embedment was investigated as well to gain insights on the distribution of strain, slip, bar stress and bond stress along the bar especially in post-yield range. A total of 12 specimens were tested, by means of pull-out of the reinforcing bars from concrete blocks. It was found that the enhancement of local bond strength can be reached up to 50% and ductility of the bond behavior was improved significantly if HPFRCC is used. Also, under a constant strain at loaded end, HPFRCC has delayed yielding of bars at other location from the loaded end. Hence, the reduction of bond stress was slower for HPFRCC in comparison with NC. Due to the same reason, the total slips at loaded end for HPFRCC was smaller than NC as expected. Test results indicated that HPFRCC has better bond slip behavior which makes it a suitable material to be employed in anchorage zone such as beam-column joints.

Keywords: Bond stress, high performance fiber reinforced cement composites, slip, strain.

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Authors: T. M. Agbede

Abstract:

Field experiments were carried out at Owo, southwest Nigeria to evaluate the effect of different tillage practices (zero tillage with mulch (ZTM), row tillage (RT) and conventional tillage (CT), and with or without oil palm bunch ash plus poultry manure (OBA+PM) on soil chemical properties, growth and yield of ginger. The experiment was laid out in a randomized complete plot design with three replications. Soil chemical properties, growth and fresh rhizome yield reduced with frequency/intensity of tillage imposed while application of OBA+PM increased them. Among the tillage practices, the highest fresh rhizome yield (15.0t ha-1) was produced by ZTM which was significantly different from other tillage practices. Among the tillage – OBA+PM combinations, the  most satisfactorily yield (20.1t ha-1) was produced by ZTM+OBA+PM while the lowest yield (15.7t ha-1) was in CT+OBA+PM.

Keywords: Oil palm bunch ash, poultry manure, rhizome yield, tillage.

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Authors: James Kuria, John Kihiu

Abstract:

This work presents a numerical model developed to simulate the dynamics and vibrations of a multistage tractor gearbox. The effect of time varying mesh stiffness, time varying frictional torque on the gear teeth, lateral and torsional flexibility of the shafts and flexibility of the bearings were included in the model. The model was developed by using the Lagrangian method, and it was applied to study the effect of three design variables on the vibration and stress levels on the gears. The first design variable, module, had little effect on the vibration levels but a higher module resulted to higher bending stress levels. The second design variable, pressure angle, had little effect on the vibration levels, but had a strong effect on the stress levels on the pinion of a high reduction ratio gear pair. A pressure angle of 25o resulted to lower stress levels for a pinion with 14 teeth than a pressure angle of 20o. The third design variable, contact ratio, had a very strong effect on both the vibration levels and bending stress levels. Increasing the contact ratio to 2.0 reduced both the vibration levels and bending stress levels significantly. For the gear train design used in this study, a module of 2.5 and contact ratio of 2.0 for the various meshes was found to yield the best combination of low vibration levels and low bending stresses. The model can therefore be used as a tool for obtaining the optimum gear design parameters for a given multistage spur gear train.

Keywords: bending stress levels, frictional torque, gear designparameters, mesh stiffness, multistage gear train, vibration levels.

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Authors: Elsa Eka Putri, N.S.V Kameswara Rao, M. A. Mannan

Abstract:

The objective of this study is to evaluate the threshold stress of the clay with sand subgrade soil. Threshold stress can be defined as the stress level above which cyclic loading leads to excessive deformation and eventual failure. The thickness determination of highways formations using the threshold stress approach is a more realistic assessment of the soil behaviour because it is subjected to repeated loadings from moving vehicles. Threshold stress can be evaluated by plastic strain criterion, which is based on the accumulated plastic strain behaviour during cyclic loadings [1]. Several conditions of the all-round pressure the subgrade soil namely, zero confinement, low all-round pressure and high all-round pressure are investigated. The threshold stresses of various soil conditions are determined. Threshold stress of the soil are 60%, 31% and 38.6% for unconfined partially saturated sample, low effective stress saturated sample, high effective stress saturated sample respectively.

Keywords: threshold stress, cyclic loading, pore water pressure.

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Authors: I. Alhassan, A. M. Saddiq, A. G. Gashua, K. K. Gwio-Kura

Abstract:

The main objective of any irrigation program is the development of an efficient water management system to sustain crop growth and development and avoid physiological water stress in the growing plants. Field experiment to evaluate the effects of some soil moisture conservation practices on yield and water use efficiency (WUE) of maize was carried out in three locations (i.e. Mubi and Yola in the northern Guinea Savannah and Ganye in the southern Guinea Savannah of Adamawa State, Nigeria) during the dry seasons of 2013 and 2014. The experiment consisted of three different irrigation levels (7, 10 and 12 day irrigation intervals), two levels of mulch (mulch and un-mulched) and two tillage practices (no tillage and minimum tillage) arranged in a randomized complete block design with split-split plot arrangement and replicated three times. The Blaney-Criddle method was used for measuring crop evapotranspiration. The results indicated that seven-day irrigation intervals and mulched treatment were found to have significant effect (P>0.05) on grain yield and water use efficiency in all the locations. The main effect of tillage was non-significant (P<0.05) on grain yield and WUE. The interaction effects of irrigation and mulch were significant (P>0.05) on grain yield and WUE at Mubi and Yola. Generally, higher grain yield and WUE were recorded on mulched and seven-day irrigation intervals, whereas lower values were recorded on un-mulched with 12-day irrigation intervals. Tillage exerts little influence on the yield and WUE. Results from Ganye were found to be generally higher than those recorded in Mubi and Yola; it also showed that an irrigation interval of 10 days with mulching could be adopted for the Ganye area, while seven days interval is more appropriate for Mubi and Yola.

Keywords: Irrigation, maize, mulching, tillage, guinea savannah.

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Authors: F. Gekas, C. Pankou, I. Mylonas, E. Ninou, E. Sinapidou, A. Lithourgidis, F. Papathanasiou, J. –K. Petrevska, F. Papadopoulou, P. Zouliamis, G. Tsaprounis, I. Tokatlidis, C. Dordas

Abstract:

The present study aimed to investigate whether chlorophyll meter readings (SPAD) can be used as criterion of singleplant selection in maize breeding. Experimentation was performed at the ultra-low density of 0.74 plants/m2 in order the potential yield per plant to be fully expressed. R-31 honeycomb experiments were conducted in three different areas in Greece (Thessaloniki, Giannitsa and Florina) using 30 inbred lines at well-watered and water-stressed conditions during the 2012 growing season. The chlorophyll meter readings had higher rates at dry conditions, except location of Giannitsa where differences were not significant. Genotypes of highest chlorophyll meter readings were consistent across areas, emphasizing on the character’s stability. A positive correlation between the chlorophyll meter readings and grain yield was strengthening over time and culminated at the physiological maturity stage. There was a clear sign that the chlorophyll meter readings has the potential to be used for the selection of stress-adaptive genotypes and may permit modern maize to be grown at wider range of environments addressing the climate change scenarios.

Keywords: Drought-prone environments, honeycomb breeding, SPAD, Zea mays.

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Authors: Sae-Rom Pak, Seung Hwan Park, Jeong Ho Cho, Daewoong An, Cheong-Sool Park, Jun Seok Kim, Jun-Geol Baek

Abstract:

It is important to predict yield in semiconductor test process in order to increase yield. In this study, yield prediction means finding out defective die, wafer or lot effectively. Semiconductor test process consists of some test steps and each test includes various test items. In other world, test data has a big and complicated characteristic. It also is disproportionably distributed as the number of data belonging to FAIL class is extremely low. For yield prediction, general data mining techniques have a limitation without any data preprocessing due to eigen properties of test data. Therefore, this study proposes an under-sampling method using support vector machine (SVM) to eliminate an imbalanced characteristic. For evaluating a performance, randomly under-sampling method is compared with the proposed method using actual semiconductor test data. As a result, sampling method using SVM is effective in generating robust model for yield prediction.

Keywords: Yield Prediction, Semiconductor Test Process, Support Vector Machine, Under Sampling

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Authors: Mohammad Reza Haj Seyed Hadi, Fereshteh Ghanepasand, Mohammad Taghi Darzi

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The main objective of this study was to determine the effects of Nitrogen fixing bacteria and manure application on the seed yield and yield components in black cumin (Nigella sativa L.). The experiment was carried out at the RAN Research Station in Firouzkouh in 2012. A 4×4 factorial experiment, arranged in a randomized complete blocks designed with three replications. Nitrogen fixing bacteria at 4 levels (control, Azotobacter, Azospirillum and Azotobacter + Azospirillum) and manure application at 4 levels (0, 2.5, 5 and 7.5 ton ha-1) were used at this investigation. The present results have shown that the highest height, 1000 seeds weight, seed number per follicle, follicle yield, seed yield and harvest index were obtained after using Azotobacter and Azospirillum, simultaneously. Manure application only effects on follicle yield and by 5ton manure ha-1 the highest follicle yield obtained. Results of this investigation showed that the maximum seed yield obtained when Aotobacter+Azospirillum inoculated with black cumin seeds and 5 ton manure ha-1 applied. According to the results of this investigation the integrated management of Azotobacter and Azospirillum with manure application is the best treatment for achieving the maximum quantitative charactersitics of Black cumin.

Keywords: Azotobacter, azospirillum, black cumin, yield, yield components.

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Authors: Tea Poklepović, Zdravka Aljinović, Branka Marasović

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Due to the importance of yield curve and its estimation it is inevitable to have valid methods for yield curve forecasting in cases when there are scarce issues of securities and/or week trade on a secondary market. Therefore in this paper, after the estimation of weekly yield curves on Croatian financial market from October 2011 to August 2012 using Nelson-Siegel and Svensson models, yield curves are forecasted using Vector autoregressive model and Neural networks. In general, it can be concluded that both forecasting methods have good prediction abilities where forecasting of yield curves based on Nelson Siegel estimation model give better results in sense of lower Mean Squared Error than forecasting based on Svensson model Also, in this case Neural networks provide slightly better results. Finally, it can be concluded that most appropriate way of yield curve prediction is Neural networks using Nelson-Siegel estimation of yield curves.

Keywords: Nelson-Siegel model, Neural networks, Svensson model, Vector autoregressive model, Yield curve.

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Authors: Ayhan Aydoğdu, Ercan Ceyhan, Ali Kahraman, Nursel Çöl

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This research was conducted to determine effects of plant densities on seed yield and some agricultural characteristics of pea variety- Jofs in Konya ecological conditions during 2012 vegetation period. The trial was set up according to “Randomized Blocks Design” with three replications. The material “Jofs” pea variety was subjected to 3-row spaces (30, 40 and 50 cm) and 3-row distances (5, 10 and 15 cm). According to the results, difference was shown statistically for the effects of row spaces and row distances on seed yield. The highest seed yield was 2582.1 kg ha-1 on 30 cm of row spaces while 2562.2 kg ha-1 on 15 cm of distances. Consequently, the optimum planting density was determined as 30 x 15 cm for Jofs pea variety growing in Konya.

Keywords: Pea, row space, row distance, seed yield.

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Authors: M.A.Grigoras, A.Popescu, D.Pamfil, I.Has, L.C.Cota

Abstract:

An experimental study is presented on the effect of Conservation Agriculture (CA) compared to Conventional Agriculture (ConvA) upon Maize Yield based on split-plot model. Two factors have been considered: A Factor-Fertilization with two variants: A1- N40P40 kg/ha and A2- N90P70 kg/ha; B Factor- Crop protection with 4 variants : B1- 4 treatments, B2-3 treatments, B3- 2 treatments and B4- 1 treatment. In comparison with conventional agriculture, CA determined lower maize yields. Fertilization is the key factor determining a yield gain of 973.58 kg/ha in ConvA and 1,123.33 kg/ha in CA. A reduced number of treatments determined a yield decline. The A-B interaction had a positive effect on maize yield when a larger amount of fertilizer and 4 or 3 treatments were applied in ConvA and a benefic in CA for highest fertilization level and 2 treatments. The B2A2 ConvA variant was the most efficient leading to 302.67 kg/ha gain while B3A2 CA variant brought 181.33 kg production gain.

Keywords: conservation agriculture, conventional agriculture, maize, yield

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Authors: Şehri Çınar, Aydın Akın

Abstract:

This study was conducted Razakı grape variety (Vitis vinifera L.) and its vine which was aged 19 was grown on 5 BB rootstock in a vegetation period of 2014 in Afyon province in Turkey. In this research, it was investigated whether the applications of Control (C), 1/3 Cluster Tip Reduction (1/3 CTR), Shoot Tip Reduction (STR), 1/3 CTR + STR, Boric Acid (BA), 1/3 CTR + BA, STR + BA, 1/3 CTR + STR + BA on yield and yield components of Razakı grape variety. The results were obtained as the highest fresh grape yield (7.74 kg/vine) with C application; as the highest cluster weight (244.62 g) with STR application; as the highest 100 berry weight (504.08 g) with C application; as the highest maturity index (36.89) with BA application; as the highest must yield (695.00 ml) with BA and (695.00 ml) with 1/3 CTR + STR + BA applications; as the highest intensity of L* color (46.93) with STR and (46.10) with 1/3 CTR + STR + BA applications; as the highest intensity of a* color (-5.37) with 1/3 CTR + STR and (-5.01) with STR, as the highest intensity of b* color (12.59) with STR application. The shoot tip reduction to increase cluster weight and boric acid application to increase maturity index of Razakı grape variety can be recommended.

Keywords: Razakı, 1/3 cluster tip reduction, shoot tip reduction, boric acid, yield and yield components.

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Authors: N. Rezvani, A. Sorooshzadeh, N. Farhadi

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Saffron (Crocus sativus) is cultivated as spices, medicinal and aromatic plant species. At autumn season, heavy rainfall can cause flooding stress and inhibits growth of saffron. Thus this research was conducted to study the effect of silver ion (as an ethylene inhibitor) on growth of saffron under flooding conditions. The corms of saffron were soaked with one concentration of nano silver (0, 40, 80 or 120 ppm) and then planting under flooding stress or non flooding stress conditions. Results showed that number of roots, root length, root fresh and dry weight, leaves fresh and dry weight were reduced by 10 day flooding stress. Soaking saffron corms with 40 or 80 ppm concentration of nano silver rewarded the effect of flooding stress on the root number, by increasing it. Furthermore, 40 ppm of nano silver increased root length in stress. Nano silver 80 ppm in flooding stress, increased leaves dry weight.

Keywords: Flooding stress, Nano-silver, Saffron.

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Authors: Kanlaya Kong-ngern, Tossapol Buaphan, Duangsamorn Tulaphitak, Naug Phuvongpha, Sirirut Wongpakonkul, Piyada Threerakulpisut

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Pearson-s correlation coefficient and sequential path analysis has been used for determining the interrelationship among yield, yield components, soil minerals and aroma of Khao Dawk Mali (KDML) 105 rice grown in the area of Tungkularonghai in Roi-Et province, located in the northeast of Thailand. Pearson-s correlation coefficient in this study showed that the number of panicles was the only factor that had positive significant (0.790**) effect on grain yield. Sequential path analysis revealed that the number of panicles followed by the number of fertile spikelets and 100-grain weight were the first-order factors which had positive direct effects on grain yield. Whereas, other factors analyzed had indirect effects influencing grain yield. This study also indicated that no significant relationship was found between the aroma level and any of the factors analyzed.

Keywords: 2-Acetyl-1-Pyrroline, rice aroma

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Authors: S. Boonlertnirun, R. Suvannasara, K. Boonlertnirun

Abstract:

Hypoxia has negative effects on growth and crop yield, its severity is so varied depending on crop growth stages, duration of hypoxia and crop species. The objective was to evaluate the sensitive growth stage and the duration of hypoxia negatively affecting growth and yield of waxy corn. Pot experiment was conducted using a split plot in randomized complete block with 3 growth stages: V3 (3-4 true leaves), V7 (7-8 true leaves) and R1 (silking stage), and 3 hypoxic durations: 6, 9 and 12 days, in an open –ended outdoor greenhouse during January to March 2013. The results revealed that different growth stages had significantly (p < 0.5) different responses to hypoxia, seeing that the sensitive growth stage affecting plant height, yield and yield components was mostly detected in V7 growth stage whereas leaf greenness and days to silking were sensitive to hypoxia at R1 growth stage. Different hypoxic durations significantly affected yield and yield components, hypoxic duration of 12 days showed the most negative effect greater than the others. In this present study, it can be concluded that waxy corn plants were waterlogged at V7 growth stage for 12 days had the most negative effect on yield and yield components.

Keywords: Hypoxia duration, waxy corn, growth stage.

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Authors: Hamid Abbasdokht , Ahmad Gholami

Abstract:

In order to study of The Effect of seed inoculation with Pseudomonas putida+Bacillus lentus on yield and yield components of wheat (Triticum aestivum L.) cultivars, an experiment was carried out as factorial based on Randomized Complete Block Design (RCBD) in Agricultural Research Station of Shahrood University of Technology. Results showed that inoculation with Pseudomonas putida+Bacillus lentus promoted seed germination. Also, inoculation with Pseudomonas putida+Bacillus lentus significantly affected grain yield, Number of spikes per m2, Number of grain per spike and 1000-seed weight and There was not statistically significant difference between Chamran and Pishtaz cultivars . Finally, the dosages of chemical fertilizers currently applied in commercial wheat field in Iran (Shahrood region) could be reduced through proper combination of Pseudomonas putida+Bacillus lentus inoculation plus fertilization.

Keywords: Seed inoculation, wheat, yield, yield components

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Authors: Ali Baladi, Alireza Fallahi Arezoodar

Abstract:

in dissimilar material joints, failure often occurs along the interface between two materials due to stress singularity. Stress distribution and its concentration depend on materials and geometry of the junction. Inhomogenity of stress distribution at the interface of junction of two materials with different elastic modules and stress concentration in this zone are the main factors resulting in rupture of the junction. Effect of joining angle in the interface of aluminum-polycarbonate will be discussed in this paper. Computer simulation and finite element analysis by ABAQUS showed that convex interfacial joint leads to stress reduction at junction corners in compare with straight joint. This finding is confirmed by photoelastic experimental results.

Keywords: Elastic Modules, Stress Concentration, JoiningAngle, Photoelastic.

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Authors: S. Ghasemi, M. M. Kamelmanesh, A. Namayandeh, R. Biabanikhankahdani

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The common bean is the most important grain legume for direct human consumption in the world and BCMV is one of the world's most serious bean diseases that can reduce yield and quality of harvested product. To determine the best tolerance index to BCMV and recognize tolerant genotypes, 2 experiments were conducted in field conditions. Twenty five common bean genotypes were sown in 2 separate RCB design with 3 replications under contamination and non-contamination conditions. On the basis of the results of indices correlations GMP, MP and HARM were determined as the most suitable tolerance indices. The results of principle components analysis indicated 2 first components totally explained 98.52% of variations among data. The first and second components were named potential yield and stress susceptible respectively. Based on the results of BCMV tolerance indices assessment and biplot analysis WA8563-4, WA8563-2 and Cardinal were the genotypes that exhibited potential seed yield under contamination and noncontamination conditions.

Keywords: Phaseolus vulgaris, BCMV, principle components analysis, bi-plot analysis, tolerance.

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Authors: A. Sarıkaya, A. Akın

Abstract:

This study was carried out to investigate effects of Control (C), 18 bud/vine, 23 bud/vine, 28 bud/vine, 18 bud/vine + TKI-Humas (soil), 23 bud/vine + TKI-Humas (soil), 28 bud/vine + TKI-Humas (soil) applications on yield and yield components of Alphonse Lavallee grape cultivar. The results were obtained as the highest cluster weight (302.31 g) with 18 bud/vine application; the highest berry weight (6.31 g) with 23 bud/vine + TKI-Humas (soil) and (6.79 g) with 28 bud/vine + TKI-Humas (soil) applications; the highest maturity index (36.95) with 18 bud/vine + TKI-Humas (soil) application; the highest L* color intensity (33.99) with 18 bud/vine + TKI-Humas (soil); the highest a* color intensity (1.53) with 23 bud/vine + TKI-Humas (soil) application. The effects of applications on grape fresh yield, grape juice yield and b* color intensity values were not found statistically significant.

Keywords: Alphonse Lavallee grape cultivar, crop load, TKI-Humas substances (soil), yield, quality.

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Authors: Saad M. Howladar, Mike Dennett

Abstract:

The effect of exogenous application; seed priming or foliar spraying of salicylic acid (SA) on Yecora Rojo and Paragon wheat cv. under NaCl-salinity. Gas exchange parameters, growth parameters, yield and yield components were reduced in both cultivars under salinity stress with foliar spray and soaking seeds. Exogenous application of SA through foliar spraying or seed soaking showed a slight increases or decreases with the application method or between cultivars. SA foliar spraying exhibited a slight improvement over SA seed soaking in most parameters, particularly in Paragon. Although, seed soaking was less effective than foliar spraying, it was a slightly better with Yecora Rojo in some parameters. However, the low SA concentration; 0.5mM tended to improve most parameters in both cultivars. From data of the experiment, it has been concluded that the effect of SA depends on cultivar genotype and SA concentration.

Keywords: Salinity, Salicylic acid, Growth parameters, yield components, Wheat cultivars.

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Authors: Gholamreza Zarei, Hossein Shamsi, Farjam Fazeli

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This study carried out to determine the effect of plant densities on some agronomic characteristics of four safflower cultivars in spring planting. The experiment was conducted at Yazd, Iran- using a factorial in a randomized complete block design with four replications. Cultivars were including Arak, IL, Asteria and Local and plant densities were 10, 13.3, 20 and 40 plant/m2. Number of seeds/head, number of heads/plant, HI, 1000-seed weight and seed yield significantly decreased as planting density increased. With increasing planting density, LAI, plant height, first branch height and biological yield increased. The highest seed yield was obtained in 13.3 plant/m2 (2167 kg/ha). There were significant differences between cultivars. Local cv. had higher seed yield than the other cultivars mainly due to higher heads/plant and seeds/head.

Keywords: safflower, plant density, cultivar

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Authors: Zhuang He, Andrei Kotousov

Abstract:

All current experimental methods for determination of stress intensity factors are based on the assumption that the state of stress near the crack tip is plane stress. Therefore, these methods rely on strain and displacement measurements made outside the near crack tip region affected by the three-dimensional effects or by process zone. In this paper, we develop and validate an experimental procedure for the evaluation of stress intensity factors from the measurements of the out-of-plane displacements in the surface area controlled by 3D effects. The evaluation of stress intensity factors is possible when the process zone is sufficiently small, and the displacement field generated by the 3D effects is fully encapsulated by K-dominance region.

Keywords: Digital image correlation, stress intensity factors, three-dimensional effects, transverse displacement.

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Authors: Mohammadi K., Ghalavand A., Aghaalikhani M

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In order to evaluation the effects of natural, biological and chemical fertilizers on grain yield and chickpea quality, field experiments were carried out in 2007 and 2008 growing seasons. In this research the effects of different organic, chemical and biological fertilizers were investigated on grain yield and quality of chickpea. Experimental units were arranged in split-split plots based on randomized complete blocks with three replications. The highest amounts of yield and yield components were obtained in G1×N5 interaction. Significant increasing of N, P, K, Fe and Mg content in leaves and grains emphasized on superiority of mentioned treatment because each one of these nutrients has an approved role in chlorophyll synthesis and photosynthesis ability of the crop. The combined application of compost, farmyard manure and chemical phosphorus (N5) had the best grain quality due to high protein, starch and total sugar contents, low crude fiber and reduced cooking time.

Keywords: soil fertility, grain yield, chickpea, natural resources.

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Authors: M. H. Kargarnovin, K. Momeni

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The study of the stress distribution on a hollow cylindrical fiber placed in a composite material is considered in this work and an analytical solution for this stress distribution has been constructed. Finally some parameters such as fiber-s thickness and fiber-s length are considered and their effects on the distribution of stress have been investigated. For finding the governing relations, continuity equations for the axisymmetric problem in cylindrical coordinate (r,o,z) are considered. Then by assuming some conditions and solving the governing equations and applying the boundary conditions, an equation relates the stress applied to the representative volume element with the stress distribution on the fiber has been found.

Keywords: Axial Loading, Composite, Hollow CylindricalFiber, Stress Distribution.

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Authors: T. H. Young, Y. J. Tsai

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A method for determining the stress distribution of a rectangular plate subjected to two pairs of arbitrarily distributed in-plane edge shear loads is proposed, and the free vibration and buckling of such a rectangular plate are investigated in this work.  The method utilizes two stress functions to synthesize the stress-resultant field of the plate with each of the stress functions satisfying the biharmonic compatibility equation. The sum of stress-resultant fields due to these two stress functions satisfies the boundary conditions at the edges of the plate, from which these two stress functions are determined. Then, the free vibration and buckling of the rectangular plate are investigated by the Galerkin method. Numerical results obtained by this work are compared with those appeared in the literature, and good agreements are observed.

Keywords: Stress analysis, free vibration, plate buckling, nonuniform in-plane edge shear.

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Authors: Nao-Aki Noda, Yu Zhang, Ken-Tarou Takaishi, Hiroyuki Shibahara

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In this paper the strength of adhesive joint under tension and bending is discussed on the basis of intensity of singular stress by the application of FEM. A useful method is presented with focusing on the stress at the edge of interface between the adhesive and adherent obtained by FEM. After analyzing the adhesive joint strength with all material combinations, it is found that to improve the interface strength, thin adhesive layers are desirable because the intensity of singular stress decreases with decreasing the thickness.

Keywords: Adhesive, Adherent, Intensity of singular stress, Bonded strip

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Authors: M.Mirzakhani, M.R.Ardakani , A.Aeene Band , A.H. Shirani Rad, F.Rejali

Abstract:

In order to evaluate the Effects of dual inoculation of Azotobacter and Mycorrhiza with Nitrogen and Phosphorus levels on yield and yield components of spring safflower, this study was carried out in field of Farahan university in Markazi province in 2007. A factorial in a randomized complete block design with three replications was used inoculation of Azotobacter (with inoculation and without inoculation) and Mycorrhiza (with inoculation and without inoculation ) with Nitrogen and Phosphorus levels [F0= N0+ P0 (kg.ha-1), F1= N50+ P25(kg.ha-1), F2= N100+ P50(kg.ha-1) and F3= N150+ P75 (kg.ha-1)] on spring safflower (cultivar IL-111). In this study characteristics such as: Harvest index, Hectolitre weight, Root dry weight, Seed yield, Mycorrhizal Colonization Root, Number of days to maturity were assessed. Results indicated that treatment (A0M1F3) with grain yield (1556 kg.ha-1) and treatment (A0M1F0) with grain yield (918 kg.ha-1) were significantly superior to the other treatments and according to calculated, inoculation seeds in plantig date with Azotobacter and Mycorrhiza to cause increase grain yield about 5/38 percentage. we can by inoculation safflower seeds with Azotobacter and Mycorrhiza too easily at the time sowing date. The purpose of this research, study and evaluation the role of biological fixation N and P, to provide for feeds plants.

Keywords: Spring safflower, grain yield, inoculation, Azotobacter and Mycorrhiza.

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Authors: Naser Sabaghnia, Mohsen Janmohammadi, Mehdi Mohebodini

Abstract:

Present investigation is performed to evaluate the effects of foliar application of salicylic acid, glycine betaine, ascorbic acid, nano-silica, and nano-titanium dioxide on sunflower. Results showed that the first two principal components were sufficient to create a two-dimensional treatment by trait biplot, and such biplot accounted percentages of 49% and 19%, respectively of the interaction between traits and treatments. The vertex treatments of polygon were ascorbic acid, glycine betaine, nano-TiO₂, and control indicated that high performance in some important traits consists of number of days to seed maturity, number of seeds per head, number heads per single plant, hundred seed weight, seed length, seed yield performance, and oil content. Treatments suitable for obtaining the high seed yield were identified in the vector-view function of biplot and displayed nano-silica and nano titanium dioxide as the best treatments suitable for obtaining of high seed yield.

Keywords: Drought stress, nano-silicon dioxide, oil content, TiO2 nanoparticles.

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Authors: Hossein Soleimanzadeh

Abstract:

The effect of seed inoculation by VA- mycorrhiza and different levels of phosphorus fertilizer on growth and yield of sunflower (Azargol cultivar) was studied in experiment farm of Islamic Azad University, Karaj Branch during 2008 growing season. The experiment treatments were arranged in factorial based on a complete randomized block design with three replications. Four phosphorus fertilizer levels of 25%, 50% 75% and 100% P recommended with two levels of Mycorrhiza: with and without Mycorrhiza (control) were assigned in a factorial combination. Results showed that head diameter, number of seeds in head, seed yield and oil yield were significantly higher in inoculated plants than in non-inoculated plants. Head diameter, number of seeds in head, 1000 seeds weight, biological yield, seed yield and oil yield increased with increasing P level above 75% P recommended in non-inoculated plants, whereas no significant difference was observed between 75% and 100% P recommended. The positive effect of mycorrhizal inoculation decreased with increasing P levels due to decreased percent root colonization at higher P levels. According to the results of this experiment, application of mycorrhiza in present of 50% P recommended had an appropriate performance and could increase seed yield and oil production to an acceptable level, so it could be considered as a suitable substitute for chemical phosphorus fertilizer in organic agricultural systems.

Keywords: phosphorus fertilizer, seed yield, sunflower, VA-mycorrhiza

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Authors: A. Akın, H. Çoban

Abstract:

This study was carried out to determine the effects of Control (C), 1/3 Cluster Tip Reduction (1/3 CTR), 1/6 Cluster Tip Reduction (1/6 CTR), 1/9 Cluster Tip Reduction (1/9 CTR), 1/3 CTR + Boric Acid (BA), 1/6 CTR + BA, 1/9 CTR + BA applications on yield and yield components of four years old Alphonse Lavallee grape variety (Vitis vinifera L.) grown on grafted 110 Paulsen rootstock in Konya province in Turkey in the vegetation period in 2015. According to the results, the highest maturity index 21.46 with 1/9 CTR application; the highest grape juice yields 736.67 ml with 1/3 CTR + BA application; the highest L* color value 32.07 with 1/9 CTR application; the highest a* color value 1.74 with 1/9 CTR application; the highest b* color value 3.72 with 1/9 CTR application were obtained. The effects of applications on grape fresh yield, cluster weight and berry weight were not found statistically significant.

Keywords: Alphonse Lavallee grape cultivar, different cluster tip reduction (1/3, 1/6, 1/9), foliar boric acid application, yield, quality.

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